Next Article in Journal
Tempters and Gluten-Free Diet
Next Article in Special Issue
Effect of Tea Polyphenol Compounds on Anticancer Drugs in Terms of Anti-Tumor Activity, Toxicology, and Pharmacokinetics
Previous Article in Journal
Vitamin D Status and Efficacy of Vitamin D Supplementation in Atopic Dermatitis: A Systematic Review and Meta-Analysis
Previous Article in Special Issue
Anticancer Effects of Rosemary (Rosmarinus officinalis L.) Extract and Rosemary Extract Polyphenols
Article Menu

Export Article

Nutrients 2016, 8(12), 785; doi:10.3390/nu8120785

Review
Polyphenols and DNA Damage: A Mixed Blessing
1
Department of Pharmacology and Toxicology, Faculty of Pharmacy, University of Navarra, C/Irunlarrea 1, 31009 Pamplona, Spain
2
IdiSNA, Navarra Institute for Health Research
3
Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, PB 1046 Blindern, 0316 Oslo, Norway
*
Author to whom correspondence should be addressed.
Received: 11 October 2016 / Accepted: 23 November 2016 / Published: 3 December 2016

Abstract

:
Polyphenols are a very broad group of chemicals, widely distributed in plant foods, and endowed with antioxidant activity by virtue of their numerous phenol groups. They are widely studied as putative cancer-protective agents, potentially contributing to the cancer preventive properties of fruits and vegetables. We review recent publications relating to human trials, animal experiments and cell culture, grouping them according to whether polyphenols are investigated in whole foods and drinks, in plant extracts, or as individual compounds. A variety of assays are in use to study genetic damage endpoints. Human trials, of which there are rather few, tend to show decreases in endogenous DNA damage and protection against DNA damage induced ex vivo in blood cells. Most animal experiments have investigated the effects of polyphenols (often at high doses) in combination with known DNA-damaging agents, and generally they show protection. High concentrations can themselves induce DNA damage, as demonstrated in numerous cell culture experiments; low concentrations, on the other hand, tend to decrease DNA damage.
Keywords:
polyphenols; flavonoids; human studies; in vitro; in vivo; DNA damage; DNA protection

1. Introduction

For many years now it has been recognised that fruits and vegetables play an important role in preventing or alleviating the effects of various chronic diseases, notably cardiovascular disease and various cancers. The mechanism(s) of this protection is still not clear. A common explanation is the so-called antioxidant hypothesis; oxidative stress is a factor in many diseases; fruits and vegetables contain various phytochemicals with antioxidant properties, and so these are likely to be the agents of protection. This is clearly a simplistic hypothesis; phytochemicals have been shown to have a wide array of influences on the physiological processes of human cells, and reducing them to sources of antioxidant activity is misguided and misleading. A meta-analysis of clinical trials indicates that antioxidant phytochemicals taken as supplements have no beneficial effect on mortality and may even increase it [1]. In natural plant foods, of course, phytochemicals of different kinds are present, acting in concert, often in all likelihood synergistically, and so studies of whole foods or extracts are particularly valuable. The reductionist approach (looking at individual components) is still popular, however, as evidenced by the large number of studies of individual phytochemicals, and by the growing catalogue of plant species that have been extracted and tested for potential health-promoting effects using a range of molecular markers. DNA damage is one of the most commonly employed such markers, in the reasonable belief that a decrease in DNA damage—as the initiating event of carcinogenesis—must signify a decrease in cancer risk.
Currently, the most popular assay for DNA damage at the cellular level is single cell gel electrophoresis, or the comet assay [2]. It is based on the ability of a strand break (SB) to relax supercoiling in a loop of DNA, thus allowing the DNA to extend to the anode during electrophoresis forming a comet-like image in which the relative intensity of the comet tail reflects the break frequency. Strand breakage is a feature of some but not all kinds of DNA-damaging agent. Reactive oxygen species, in particular, tend to cause damage to DNA bases. An example of base oxidation is 8-oxo–7,8-dihydroguanine (8-OH–Gua). This is converted to a SB by the action of formamidopyrimidine DNA glycosylase (Fpg)—a bacterial repair enzyme, and a simple modification of the comet assay, incorporating an enzymic digestion of the DNA after lysis of cells in agarose—allows the detection of oxidised purines. An analogous enzyme, endonuclease III (or Nth) converts oxidised pyrimidines to SBs. In the search for antioxidant protection of cells against such damage, it is surprising that so few published studies actually use the enzyme-modified comet assay.
The measurement of resistance to H2O2-induced damage is a good marker of cellular antioxidant status. Typically, cells are exposed in vitro to 50–100 μM H2O2 for a brief period, and the yield of SBs is measured with the basic comet assay; the lower the break frequency, the higher the antioxidant status.
The base 8-OH–Gua and the nucleosides 8-OH–Guo and 8-OH–dGuo can be detected in tissues, but are more commonly measured in urine, plasma or serum, using high performance liquid chromatography (often linked with mass spectrometry) and antibody-based techniques (ELISA or immunohistochemistry). In the tables and text that follow, we use the abbreviation 8-OH–G to cover all three compounds, as the oxidised base is the common factor. They are markers of oxidative stress [3,4]; free 8-OH–Gua can arise through cellular DNA base excision repair, though the origin of the oxidised nucleosides is not certain.
γ-H2AX is the phosphorylated form of histone H2AX, which appears at the site of DNA damage (particularly double SBs); it is detected by immunocytochemistry [5], or sometimes by immunofluorescence combined with flow cytometry [6], and is a sensitive damage indicator.
Unrepaired DNA damage can result in alterations at the level of chromosomes. Classically, chromosome aberrations (chrom abs) were studied as an index of genomic instability, but now the presence of micronuclei (MN: fragments of chromosomes or whole chromosomes that segregate as discrete bodies at mitosis) is a more common marker [7]. Both chrom abs and MN have been confirmed—in long-term human clinical studies—as prospective markers of cancer risk [8,9].
Here, we summarise the results of recent investigations of effects of polyphenols—a very broad class of phytochemicals—on DNA damage, at the level of humans, in animal experiments, and in in vitro studies using cultured (usually human) cells.

2. Methods

In this review, we have concentrated on papers published from 2010 to the present. We used PubMed with the followings terms in the title or abstract: polyphenols/polyphenol/flavonoids/flavonoid combined with DNA damage/DNA protection/DNA repair. We found a total of 386 papers. We have concentrated on papers where the effect of polyphenols, in the form of real food, plant extract or pure compound, is tested in cell culture, animals and humans. We have excluded papers where only gene expression was studied, papers specifically focused on other diseases than cancer, and papers, for example, with deficient experimental design. Papers in which the main interest is in the induction of apoptosis were also excluded.
The reports are summarised in tables according to whether they deal with whole foods (or drinks) (Table 1), with extracts of plants (Table 2), or with single phytochemicals (Table 3). Studies are further classified as ‘in humans’, ‘in vivo’ (animal studies), or ‘in vitro’ (experiments with cultured cells). Extracts and phytochemicals are, where possible, grouped according to functional, chemical or botanical relationships (such as ‘tea and coffee related compounds’, or ‘flavonoids’, or ‘Lamiaceae’). We have generally excluded in vitro experiments with plants or compounds appearing in just one or two publications, unless they fall into one of these groups.

3. Results

3.1. Whole Foods and Drinks

Relatively few investigations of effects of whole foods on genetic damage endpoints have been published. A variety of fruit-derived drinks as well as tea (though this could be considered an extract), and dark chocolate, were tested in human supplementation trials. A decrease in urinary 8-OH–G was seen in overweight or obese adults supplemented with orange juice [10] but levels of plasma 8-OH–G in triathletes were too low to see any effect of Aronia-citrus juice [11]. De-alcoholised wine given daily for one month was without effect on DNA SBs or Fpg-sites in peripheral blood mononuclear (PBMN) cells of post-menopausal women [13]. However, a daily blueberry drink taken for 6 weeks protected PBMN cells from H2O2-induced damage, but had no effect on SBs or DNA repair capacity [14]. Malhomme de la Roche et al. [15] found that ingestion of green tea protected PBMN cells challenged ex vivo with UV(A)/VIS (ultraviolet(A)/visible) radiation, but only in some subjects, described as responders. Alleva et al. [16] gave a honey supplement to humans exposed to pesticides, and found, after two weeks’ supplementation, lower levels of EndoIII- and Fpg-sensitive sites in lymphocytes as well as an enhanced capacity for DNA repair. Dark chocolate induced a transient protection against H2O2-induced DNA damage in PBMN cells ex vivo [12].
Most of the animal studies have looked at the possible protection afforded by polyphenol-rich foods or drinks against DNA damage induced by treating the animals (rats or mice) with known carcinogens such as doxorubicin (Dox), n-nitrosodiethylamine, or sodium arsenite. Protection was claimed with Chrysobalanus icaco fruit [17], Piquia pulp [19], Açai pulp [20], and tea [18,22]; but cloudy apple juice actually increased SBs and had no effect on nitrosamine-induced damage [21]. Treatment of hyperlipidemic rats with spinach increased the resistance of blood cells ex vivo to H2O2-induced damage [23].
Experiments with cultured cells and whole foods/drinks are understandably rarely performed. Incubation of PBMN cells with green tea decreased DNA damage at low concentrations but increased it at the highest concentration tested (representing 71 mM catechins) [24]. Various honeys afforded slight protection of HepG2 cells against SBs produced by treatment with certain organic carcinogens [26]. A Chinese herbal preparation caused SBs in mouse lymphoma cells and rat fibroblasts, but at extreme concentrations (1–13 mg/mL) [25].

3.2. Extracts of Plants

3.2.1. Tea-Related Extracts

One human trial and several animal experiments have been reported with tea-related extracts. Post-menopausal women with osteoporosis were supplemented with green tea polyphenols for 6 months; the level of urinary 8-OH–G decreased [27]. Xu et al. [28] found a decrease in 8-OH–G in rats given a very high dose of green tea polyphenols. Protective effects of green tea extracts against genetic damage were reported by Garcia-Rodriguez et al. [30] in mice treated with Cr(IV); and by Pu et al. [31] in rats treated with acrylonitrile. Katiyar et al. [29] found that green tea polyphenols promoted the repair of UV-induced DNA lesions in mice proficient in nucleotide excision repair (NER), but not in NER- mice. Two studies with cultured cells have found increases in DNA SBs induced by green tea extract; Prasad et al. [35] in melanoma cell lines (though at rather high concentrations), and Durgo et al. [36] in a human laryngeal carcinoma cell line.

3.2.2. Lamiaceae Family Plants

The Lamiaceae family includes many plants used as culinary herbs, and so they have been grouped together here. All publications in our search deal with effects in cell culture.
Calo et al. [39] tested an extract of Thymus vulgaris (and thymol in parallel) on keratinocytes irradiated with UV(A) or UV(B); they found a decrease in SBs, though no effect on MN or γ-H2AX foci. A similar protective effect was reported by Cornaghi et al. [38] in a human skin model exposed to UV(B). A citrus and rosemary extract (but at high concentrations) decreased the frequency of MN induced by X-rays in human lymphocytes, and decreased UV(B)-induced SBs in keratinocytes [37]. This last group also tested lemon balm extract on UV(B)-irradiated keratinocytes and found a decrease in SBs (at a high concentration) and in γ-H2AX foci at a more moderate concentration [40]. Thirugnanasampandan et al. [42] studied three Lamiaceae species; HepG2 cells were incubated for 4 h with an extract before treating with CdCl2. Dose-dependent decreases in SBs were seen with all three (though even the lowest concentration tested was high). An extract of Ocimum sanctum (a form of basil) was tested by Venuprasad et al. [41] on human neuroblastoma cells; it protected against H2O2-induced SBs (at a high concentration).

3.2.3. Honey-Related Extracts

In parallel experiments to their human honey trial, Alleva et al. [16] showed that pre-treatment of cells with honey extract protected against pesticide-induced DNA damage and inhibition of DNA repair. Propolis extract (at high concentration) decreased the frequency of γ-ray-induced SBs in fibroblasts [50], and yet—at a much lower concentration—it caused oxidative damage (SBs measured with Fpg and EndoIII together in the comet assay) in a human cancer cell line, which was suppressed by antioxidants or catalase and so was imputed to the production of H2O2 [51].

3.2.4. Fruits and Berries

All papers on extracts of fruits and berries reviewed here describe cell culture experiments and with one exception they have made use of high to extremely high extract concentrations. The extract of one Australian fruit (among several studied) caused an increase in MN [48]. Other reports are of protection against oxidation damage caused by H2O2 [43,44,46]; or tert-butyl-hydroperoxide (t-BOOH) [45,49]. The exception to usage of high doses is a report by Bellion et al. [47] with apple polyphenol extracts; they found that 24 h pre-incubation of Caco2 cells decreased the DNA damage induced by menadione (low concentrations actually giving the greatest protection).

3.2.5. Miscellaneous Plant Extracts

Animal experiments with various plant extracts have shown protection against SB production in liver cells of pyrogallol-treated rats (at very high doses of extract) [34]; accelerated rejoining of γ-ray-induced DNA SBs [33]; and a decrease in pyrimidine dimers in the skin of UV(B)-irradiated mice [32].

4. Isolated Phytochemicals

4.1. Compounds Related to Tea and Coffee

Compounds tested—caffeic acid, chafuroside B, chlorogenic acid, ellagic acid, epicatechin, epicatechin gallate, epigallocatechin gallate, theaflavin.
One human trial with epigallocatechin gallate in prostate cancer patients showed no significant effect on 8-OH–G in leukocytes [52]. Animal studies with single polyphenols have generally involved treating mice or rats with a known DNA-damaging agent and looking for protection against DNA breaks, MN and chrom abs. Generally, protection is seen [54,57] though in some cases at rather high doses [56,63]. Pretreatment of rats with epicatechin reduced the level of DNA breaks induced in bone marrow cells by the topoisomerase poison etoposide [55]. High concentrations have also been used in in vitro experiments with cultured cells, and have given increases in SBs and γ-H2AX foci [71] and in γ-H2AX and 8-OH–G [58]. Kumar et al. [79] found that a combination of ellagic acid with curcumin (25 μM each) caused SBs while the separate compounds had no significant effect. A decrease in (background) SBs with epigallocatechin gallate or epicatechin gallate was reported by Durgo et al. [36] at 48 but not 72 h. At more reasonable concentrations, the results are mixed: decreases in UV(B)-induced SBs [70] and cyclobutane pyrimidine dimers [72]; decreases in H2O2-induced SBs and MN [74]; a decrease in SBs induced by cumene hydroperoxide [75]; but SBs and Fpg-sites increased in tetradecanoyl phorbol acetate (TPA)-stimulated neutrophils [78] and an increase in SBs with ellagic acid in prostate cancer cells was reported by Vanella et al. [73] at concentrations of 9 μM in one of the cell lines but higher concentrations in two other lines.

4.2. Curcumin

Curcumin was examined alongside epicatechin by Papiez [55]; at high concentration (up to 0.2 g/kg/day), it decreased DNA damage in the bone marrow of rats treated with etoposide. In cultured cells, curcumin at rather high concentrations caused SBs [85,86] and γ-H2AX foci [83]. The production of SBs in combination with ellagic acid was noted above [79]. Lewinska et al. [81] reported a pro-oxidant effect of curcumin at concentrations of 10 μM (and below), indicated by an increase in 8-oxo–G in smooth muscle cells. Sebastia et al. [80] compared effects of curcumin on human lymphocytes, both stimulated by TPA and unstimulated, and γ-irradiated. In non-cycling cells, the phytochemical was radioprotective (decreasing the level of premature chromosome condensation), whereas in cycling cells it acted as a radiosensitiser, increasing the frequency of chrom abs.

4.3. Resveratrol

At high concentration, in human lymphocytes, resveratrol decreased the frequency of chromosome aberrations caused by aflatoxin [87]. At a lower concentration, it protected human epithelial cells against SBs and MN induced by sodium arsenite [88], and rat astrocytes against SBs caused by ethanol [91]. However, a low dose enhanced the frequency of γ-H2AX foci after ionising irradiation of prostate epithelial cells [90]. A moderately high concentration applied to colon cancer cells caused γ-H2AX foci, apparently as a result of topoisomerase II poisoning [89]. SBs as well as Fpg-sites were increased in non-cycling cells but decreased in TPA-stimulated, cycling cells [78]. In contrast, Sebastia et al. [80] found that, as with curcumin, effects of resveratrol on irradiated lymphocytes differed depending on whether the cells were non-cycling (showing a decrease in premature chromosome condensation), or cycling (in which it had the opposite effect, acting as a radiosensitiser, increasing chromosome aberrations).

4.4. Flavonoids

Kozics et al. [97] performed a useful comparative study of 10 flavonoids, concluding that their effectiveness at protecting against B(a)P-induced SBs and MN depended on their chemical structure. Tested over a relatively low concentration range, fisetin, quercetin, galangin, kaempferol and luteolin (in order of decreasing effectiveness) were more effective than chrysin,7-hydroxyflavone, 7,8-dihydroxyflavone or baicalein, while rutin was without effect.
Among the flavonoids, quercetin appears most often in this survey. At low concentrations, SBs induced by aflatoxin B1 (AFB1), methyl methanesulphonate (MMS), Dox, HgCl2 or methyl mercury in HepG2 cells were decreased [100,101]. At high concentrations, quercetin and also rutin (glycoside of quercetin with rutinose) caused massive γ-H2AX foci, probably reflecting lethality [94], and yet they decreased DNA damage (SBs) induced by food mutagens PhIP and IQ [96].
Quercitrin, the rhamnose glycoside of quercetin, protected mouse epidermal cells against UV(B)-induced SBs [102]. Rutin at low concentrations showed the same protective effect as quercetin on HepG2 cells treated with AFB1, MMS or Dox [100]; at much higher concentrations, it caused SBs, but still protected against MN induced by B(a)P [93].
The myricetin rhamnoside, myricitrin, at high concentrations, induced MN in TK6 cells; the aglycone myricetin, being more cytotoxic, was tested at lower concentrations, and gave equivocal results [65]. Kaempferol at high concentrations induced SBs [95,99], as did fisetin [98]. Galangin and chrysin caused base oxidation at the moderate concentration of 20 μM [51], while a low concentration of naringin was protective against cadmium-induced chromosome aberrations [92]. Apigenin at a high concentration decreased SBs, chrom abs and MN [69].

5. Discussion and Conclusions

Many of the papers that we have reviewed report experiments with high or very high concentrations of phytochemicals. When investigating the role of phytochemicals in normal human nutrition, the aim should always be to study concentrations close to those likely to be present in humans as a result of dietary intake. As a rule of thumb, we have assumed this concentration to be in the low micromolar range. Many papers quote concentrations in μg/mL. To convert these concentrations to micromolar, again as a rule of thumb, we have assumed a molecular weight of 500; then 1 μg/mL = 2 μM. We would regard a concentration of over 20 μM or 10 μg/mL as high, and over 50 μM or 25 μg/mL as very high. Clearly, in functional foods or phytochemical supplements, the concentration is likely to be higher than in natural foods, and experiments showing genotoxicity of phytochemicals at high doses should at least serve as a warning to designers of functional foods.
It is always instructive to carry out experiments over a range of concentrations. Often, in the case of micronutrients in general, the dose–response curve is U-shaped, i.e., a beneficial effect at low concentrations changes to a detrimental effect at higher concentrations, and this tendency is clear in many of the reports described here.
Of course, if genotoxicity is specifically directed to cancer cells while healthy cells are unaffected, it is regarded as beneficial, and it is evidently the aim of some of the papers that we have reviewed to identify plant extracts or particular polyphenols that have such targeted action and so might have potential value as therapeutic agents. The differential response of cycling vs non-cycling cells to certain polyphenols might be exploited therapeutically in targeting dividing cancer cells.
With such a wide-ranging set of phytochemicals, not to mention the variety of test systems, experimental designs and assays applied in their study, it is difficult to generalise. However, high concentrations are likely to show DNA-damaging effects, while also in many cases protecting cells against damaging effects of other agents, apparently acting as pro-oxidants when present alone, but as anti-oxidants in combination. This is not a novel observation: many years ago, Duthie et al. reported DNA-damaging effects of quercetin at 50 μM [103] alongside an ability to protect cells against H2O2-induced DNA damage at concentrations of 10–50 μM [104]. Low concentrations are generally protective, in some cases even decreasing the already low background level of cellular DNA damage.
To summarise, results reported in the recent literature, on the whole, lend support to the hypothesis that dietary polyphenols protect the body against the effects of reactive oxygen species on DNA integrity, but do so reliably only when present at low concentrations. We recommend that greater attention be paid to the concentrations used, particularly in in vitro experiments, if the results are to be extrapolated to issues of human health. An important consideration when extrapolating is that plant foods contain a variety of micronutrients which might be expected to act in concert, whereas most experiments are carried out with single compounds. In this respect, there are clear advantages in using plant extracts or whole foods, though this approach does present practical difficulties. We also recommend that, since oxidative damage to DNA, and its prevention, are of major concern, the modified comet assay incorporating Fpg or EndoIII should be employed, since it provides increased sensitivity and specificity.

Acknowledgments

A.A. thanks the Ministerio de Economía y Competitividad (‘Ramón y Cajal’ programme, RYC-2013-14370) of the Spanish Government for personal support. This work was also supported by the BIOGENSA project (AGL2015-70640-R) of the ‘Ministerio de Economía y Competitividad’ of the Spanish Government.

Conflicts of Interest

The authors declare no conflict of interest.

Abbreviations

SBstrand break
Fpgformamidopyrimidine DNA glycosylase
EndoIIIendonuclease III (Nth)
8-OH–Gua (8-OH–G)8-oxo–7,8-dihydroguanine
PBMNperipheral blood mononuclear
NERnucleotide excision repair
Abantibody
NPnanoparticle
Doxdoxorubicin
B(a)Pbenzo(a)phenol
CPDcyclobutane pyrimidine dimer
t-BOOHtert-butyl hydroperoxide
PCBpolychlorinated biphenyls
DENdiethylnitrosamine
TPAtetradecanoyl-phorbol acetate

References

  1. Bjelakovic, G.; Nikolova, D.; Gluud, L.L.; Simonetti, R.G.; Gluud, C. Mortality in randomized trials of antioxidant supplements for primary and secondary prevention: Systematic review and meta-analysis. J. Am. Med. Assoc. 2007, 297, 842–857. [Google Scholar] [CrossRef] [PubMed]
  2. Azqueta, A.; Collins, A.R. The essential comet assay: A comprehensive guide to measuring DNA damage and repair. Arch. Toxicol. 2013, 87, 949–968. [Google Scholar] [CrossRef] [PubMed]
  3. Kasai, H. Analysis of a form of oxidative DNA damage, 8-hydroxy-2′-deoxyguanosine, as a marker of cellular oxidative stress during carcinogenesis. Mutat. Res./Rev. Mutat. Res. 1997, 387, 147–163. [Google Scholar] [CrossRef]
  4. Kasai, H.; Kawai, K. 8-hydroxyguanine, an oxidative DNA and RNA modification. In Modified Nucleic Acids in Biology and Medicine; Jurga, S.E., Erdmann, V.A., Barciszewski, J., Eds.; Springer: Basel, Switzerland, 2016; pp. 147–185. [Google Scholar]
  5. Sedelnikova, O.A.; Rogakou, E.P.; Panyutin, I.G.; Bonner, W.M. Quantitative detection of (125)idu-induced DNA double-strand breaks with gamma-h2ax antibody. Radiat. Res. 2002, 158, 486–492. [Google Scholar] [CrossRef]
  6. Huang, X.; Darzynkiewicz, Z. Cytometric assessment of histone h2ax phosphorylation: A reporter of DNA damage. Methods Mol. Biol. 2006, 314, 73–80. [Google Scholar] [PubMed]
  7. Fenech, M. Cytokinesis-block micronucleus cytome assay. Nat. Protoc. 2007, 2, 1084–1104. [Google Scholar] [CrossRef] [PubMed]
  8. Bonassi, S.; Norppa, H.; Ceppi, M.; Stromberg, U.; Vermeulen, R.; Znaor, A.; Cebulska-Wasilewska, A.; Fabianova, E.; Fucic, A.; Gundy, S.; et al. Chromosomal aberration frequency in lymphocytes predicts the risk of cancer: Results from a pooled cohort study of 22,358 subjects in 11 countries. Carcinogenesis 2008, 29, 1178–1183. [Google Scholar] [CrossRef] [PubMed]
  9. Bonassi, S.; El-Zein, R.; Bolognesi, C.; Fenech, M. Micronuclei frequency in peripheral blood lymphocytes and cancer risk: Evidence from human studies. Mutagenesis 2011, 26, 93–100. [Google Scholar] [CrossRef] [PubMed]
  10. Rangel-Huerta, O.D.; Aguilera, C.M.; Martin, M.V.; Soto, M.J.; Rico, M.C.; Vallejo, F.; Tomas-Barberan, F.; Perez-de-la-Cruz, A.J.; Gil, A.; Mesa, M.D. Normal or high polyphenol concentration in orange juice affects antioxidant activity, blood pressure, and body weight in obese or overweight adults. J. Nutr. 2015, 145, 1808–1816. [Google Scholar] [CrossRef] [PubMed]
  11. Garcia-Flores, L.A.; Medina, S.; Cejuela-Anta, R.; Martinez-Sanz, J.M.; Abellan, A.; Genieser, H.G.; Ferreres, F.; Gil-Izquierdo, A. DNA catabolites in triathletes: Effects of supplementation with an aronia-citrus juice (polyphenols-rich juice). Food Funct. 2016, 7, 2084–2093. [Google Scholar] [CrossRef] [PubMed]
  12. Spadafranca, A.; Martinez Conesa, C.; Sirini, S.; Testolin, G. Effect of dark chocolate on plasma epicatechin levels, DNA resistance to oxidative stress and total antioxidant activity in healthy subjects. Br. J. Nutr. 2010, 103, 1008–1014. [Google Scholar] [CrossRef] [PubMed]
  13. Giovannelli, L.; Pitozzi, V.; Luceri, C.; Giannini, L.; Toti, S.; Salvini, S.; Sera, F.; Souquet, J.M.; Cheynier, V.; Sofi, F.; et al. Effects of de-alcoholised wines with different polyphenol content on DNA oxidative damage, gene expression of peripheral lymphocytes, and haemorheology: An intervention study in post-menopausal women. Eur. J. Nutr. 2011, 50, 19–29. [Google Scholar] [CrossRef] [PubMed]
  14. Riso, P.; Klimis-Zacas, D.; Del Bo, C.; Martini, D.; Campolo, J.; Vendrame, S.; Moller, P.; Loft, S.; De Maria, R.; Porrini, M. Effect of a wild blueberry (vaccinium angustifolium) drink intervention on markers of oxidative stress, inflammation and endothelial function in humans with cardiovascular risk factors. Eur. J. Nutr. 2013, 52, 949–961. [Google Scholar] [CrossRef] [PubMed]
  15. Malhomme de la Roche, H.; Seagrove, S.; Mehta, A.; Divekar, P.; Campbell, S.; Curnow, A. Using natural dietary sources of antioxidants to protect against ultraviolet and visible radiation-induced DNA damage: An investigation of human green tea ingestion. J. Photochem. Photobiol. B Biol. 2010, 101, 169–173. [Google Scholar] [CrossRef] [PubMed]
  16. Alleva, R.; Manzella, N.; Gaetani, S.; Ciarapica, V.; Bracci, M.; Caboni, M.F.; Pasini, F.; Monaco, F.; Amati, M.; Borghi, B.; et al. Organic honey supplementation reverses pesticide-induced genotoxicity by modulating dna damage response. Mol. Nutr. Food Res. 2016, 60, 2243–2255. [Google Scholar] [CrossRef] [PubMed]
  17. Venancio, V.P.; Marques, M.C.; Almeida, M.R.; Mariutti, L.R.; Souza, V.C.; Barbosa, F., Jr.; Pires Bianchi, M.L.; Marzocchi-Machado, C.M.; Mercadante, A.Z.; Antunes, L.M. Chrysobalanus icaco l. Fruits inhibit nadph oxidase complex and protect DNA against doxorubicin-induced damage in wistar male rats. J. Toxicol. Environ. Health Part A 2016, 79, 885–893. [Google Scholar] [CrossRef] [PubMed]
  18. Sinha, D.; Roy, M. Antagonistic role of tea against sodium arsenite-induced oxidative DNA damage and inhibition of DNA repair in swiss albino mice. J. Environ. Pathol. Toxicol. Oncol. 2011, 30, 311–322. [Google Scholar] [CrossRef] [PubMed]
  19. Almeida, M.R.; Darin, J.D.; Hernandes, L.C.; Aissa, A.F.; Chiste, R.C.; Mercadante, A.Z.; Antunes, L.M.; Bianchi, M.L. Antigenotoxic effects of piquia (caryocar villosum) in multiple rat organs. Plant Foods Hum. Nutr. 2012, 67, 171–177. [Google Scholar] [CrossRef] [PubMed]
  20. Ribeiro, J.C.; Antunes, L.M.; Aissa, A.F.; Darin, J.D.; De Rosso, V.V.; Mercadante, A.Z.; Bianchi Mde, L. Evaluation of the genotoxic and antigenotoxic effects after acute and subacute treatments with acai pulp (euterpe oleracea mart.) on mice using the erythrocytes micronucleus test and the comet assay. Mutat. Res. 2010, 695, 22–28. [Google Scholar] [CrossRef] [PubMed]
  21. Krajka-Kuzniak, V.; Szaefer, H.; Ignatowicz, E.; Adamska, T.; Markowski, J.; Baer-Dubowska, W. Influence of cloudy apple juice on n-nitrosodiethylamine- induced liver injury and phases i and ii biotransformation enzymes in rat liver. Acta Pol. Pharm. 2015, 72, 267–276. [Google Scholar] [PubMed]
  22. Acharyya, N.; Sajed Ali, S.; Deb, B.; Chattopadhyay, S.; Maiti, S. Green tea (camellia sinensis) alleviates arsenic-induced damages to DNA and intestinal tissues in rat and in situ intestinal loop by reinforcing antioxidant system. Environ. Toxicol. 2015, 30, 1033–1044. [Google Scholar] [CrossRef] [PubMed]
  23. Ko, S.H.; Park, J.H.; Kim, S.Y.; Lee, S.W.; Chun, S.S.; Park, E. Antioxidant effects of spinach (Spinacia oleracea L.) supplementation in hyperlipidemic rats. Prev. Nutr. Food Sci. 2014, 19, 19–26. [Google Scholar] [CrossRef] [PubMed]
  24. Ho, C.K.; Siu-wai, C.; Siu, P.M.; Benzie, I.F. Genoprotection and genotoxicity of green tea (camellia sinensis): Are they two sides of the same redox coin? Redox Rep. Commun. Free Radic. Res. 2013, 18, 150–154. [Google Scholar] [CrossRef] [PubMed]
  25. Kuhnel, H.; Adilijiang, A.; Dadak, A.; Wieser, M.; Upur, H.; Stolze, K.; Grillari, J.; Strasser, A. Investigations into cytotoxic effects of the herbal preparation abnormal savda munziq. Chin. J. Integr. Med. 2015, 53, 1–9. [Google Scholar] [CrossRef] [PubMed]
  26. Haza, A.I.; Morales, P. Spanish honeys protect against food mutagen-induced DNA damage. J. Sci. Food Agric. 2013, 93, 2995–3000. [Google Scholar] [CrossRef] [PubMed]
  27. Qian, G.; Xue, K.; Tang, L.; Wang, F.; Song, X.; Chyu, M.C.; Pence, B.C.; Shen, C.L.; Wang, J.S. Mitigation of oxidative damage by green tea polyphenols and tai chi exercise in postmenopausal women with osteopenia. PLoS ONE 2012, 7, e48090. [Google Scholar] [CrossRef] [PubMed]
  28. Xu, Y.; Zhang, J.J.; Xiong, L.; Zhang, L.; Sun, D.; Liu, H. Green tea polyphenols inhibit cognitive impairment induced by chronic cerebral hypoperfusion via modulating oxidative stress. J. Nutr. Biochem. 2010, 21, 741–748. [Google Scholar] [PubMed]
  29. Katiyar, S.K.; Vaid, M.; van Steeg, H.; Meeran, S.M. Green tea polyphenols prevent uv-induced immunosuppression by rapid repair of DNA damage and enhancement of nucleotide excision repair genes. Cancer Prev. Res. 2010, 3, 179–189. [Google Scholar] [CrossRef] [PubMed]
  30. Garcia-Rodriguez Mdel, C.; Carvente-Juarez, M.M.; Altamirano-Lozano, M.A. Antigenotoxic and apoptotic activity of green tea polyphenol extracts on hexavalent chromium-induced DNA damage in peripheral blood of cd-1 mice: Analysis with differential acridine orange/ethidium bromide staining. Oxidative Med. Cell. Longev. 2013, 2013, 486419. [Google Scholar] [CrossRef] [PubMed]
  31. Pu, X.; Wang, Z.; Zhou, S.; Klaunig, J.E. Protective effects of antioxidants on acrylonitrile-induced oxidative stress in female f344 rats. Environ. Toxicol. 2015. [Google Scholar] [CrossRef] [PubMed]
  32. Olteanu, E.D.; Filip, A.; Clichici, S.; Daicoviciu, D.; Achim, M.; Postescu, I.D.; Bolfa, P.; Bolojan, L.; Vlase, L.; Muresan, A. Photochemoprotective effect of calluna vulgaris extract on skin exposed to multiple doses of ultraviolet b in skh-1 hairless mice. J. Environ. Pathol. Toxicol. Oncol. 2012, 31, 233–243. [Google Scholar] [CrossRef] [PubMed]
  33. Chaudhary, P.; Shukla, S.K.; Sharma, R.K. Rec-2006-a fractionated extract of podophyllum hexandrum protects cellular DNA from radiation-induced damage by reducing the initial damage and enhancing its repair in vivo. Evid.-Based Complement. Altern. Med. 2011, 2011, 473953. [Google Scholar] [CrossRef] [PubMed]
  34. Matic, S.; Stanic, S.; Bogojevic, D.; Vidakovic, M.; Grdovic, N.; Dinic, S.; Solujic, S.; Mladenovic, M.; Stankovic, N.; Mihailovic, M. Methanol extract from the stem of cotinus coggygria scop., and its major bioactive phytochemical constituent myricetin modulate pyrogallol-induced DNA damage and liver injury. Mutat. Res. 2013, 755, 81–89. [Google Scholar] [CrossRef] [PubMed]
  35. Prasad, R.; Katiyar, S.K. Polyphenols from green tea inhibit the growth of melanoma cells through inhibition of class i histone deacetylases and induction of DNA damage. Genes Cancer 2015, 6, 49–61. [Google Scholar] [PubMed]
  36. Durgo, K.; Kostic, S.; Gradiski, K.; Komes, D.; Osmak, M.; Franekic, J. Genotoxic effects of green tea extract on human laryngeal carcinoma cells in vitro. Arch. Hig. Rada Toksikol. 2011, 62, 139–146. [Google Scholar] [CrossRef] [PubMed]
  37. Perez-Sanchez, A.; Barrajon-Catalan, E.; Caturla, N.; Castillo, J.; Benavente-Garcia, O.; Alcaraz, M.; Micol, V. Protective effects of citrus and rosemary extracts on uv-induced damage in skin cell model and human volunteers. J. Photochem. Photobiol. B Biol. 2014, 136, 12–18. [Google Scholar] [CrossRef] [PubMed]
  38. Cornaghi, L.; Arnaboldi, F.; Calo, R.; Landoni, F.; Baruffaldi Preis, W.F.; Marabini, L.; Donetti, E. Effects of uv rays and thymol/thymus vulgaris l. Extract in an ex vivo human skin model: Morphological and genotoxicological assessment. Cells Tissues Organs 2016, 201, 180–192. [Google Scholar] [CrossRef] [PubMed]
  39. Calo, R.; Visone, C.M.; Marabini, L. Thymol and thymus vulgaris L. Activity against uva- and uvb-induced damage in nctc 2544 cell line. Mutat. Res. Genet. Toxicol. Environ. Mutagen. 2015, 791, 30–37. [Google Scholar] [CrossRef] [PubMed]
  40. Perez-Sanchez, A.; Barrajon-Catalan, E.; Herranz-Lopez, M.; Castillo, J.; Micol, V. Lemon balm extract (Melissa officinalis L.) promotes melanogenesis and prevents uvb-induced oxidative stress and DNA damage in a skin cell model. J. Dermatol. Sci. 2016, 84, 169–177. [Google Scholar] [CrossRef] [PubMed]
  41. Venuprasad, M.P.; Hemanth Kumar, K.; Khanum, F. Neuroprotective effects of hydroalcoholic extract of ocimum sanctum against h2o2 induced neuronal cell damage in sh-sy5y cells via its antioxidative defence mechanism. Neurochem. Res. 2013, 38, 2190–2200. [Google Scholar] [CrossRef] [PubMed]
  42. Thirugnanasampandan, R.; Jayakumar, R. Protection of cadmium chloride induced DNA damage by lamiaceae plants. Asian Pac. J. Trop. Biomed. 2011, 1, 391–394. [Google Scholar] [CrossRef]
  43. Giampieri, F.; Alvarez-Suarez, J.M.; Tulipani, S.; Gonzales-Paramas, A.M.; Santos-Buelga, C.; Bompadre, S.; Quiles, J.L.; Mezzetti, B.; Battino, M. Photoprotective potential of strawberry (fragaria x ananassa) extract against uv-a irradiation damage on human fibroblasts. J. Agric. Food Chem. 2012, 60, 2322–2327. [Google Scholar] [CrossRef] [PubMed]
  44. Giampieri, F.; Alvarez-Suarez, J.M.; Mazzoni, L.; Forbes-Hernandez, T.Y.; Gasparrini, M.; Gonzalez-Paramas, A.M.; Santos-Buelga, C.; Quiles, J.L.; Bompadre, S.; Mezzetti, B.; et al. Polyphenol-rich strawberry extract protects human dermal fibroblasts against hydrogen peroxide oxidative damage and improves mitochondrial functionality. Molecules 2014, 19, 7798–7816. [Google Scholar] [CrossRef] [PubMed]
  45. Braga, P.C.; Antonacci, R.; Wang, Y.Y.; Lattuada, N.; Dal Sasso, M.; Marabini, L.; Fibiani, M.; Lo Scalzo, R. Comparative antioxidant activity of cultivated and wild vaccinium species investigated by epr, human neutrophil burst and comet assay. Eur. Rev. Med. Pharmacol. Sci. 2013, 17, 1987–1999. [Google Scholar] [PubMed]
  46. Yamamoto, A.; Nakashima, K.; Kawamorita, S.; Sugiyama, A.; Miura, M.; Kamitai, Y.; Kato, Y. Protective effects of raw and cooked blackcurrant extract on DNA damage induced by hydrogen peroxide in human lymphoblastoid cells. Pharm. Biol. 2014, 52, 782–788. [Google Scholar] [CrossRef] [PubMed]
  47. Bellion, P.; Digles, J.; Will, F.; Dietrich, H.; Baum, M.; Eisenbrand, G.; Janzowski, C. Polyphenolic apple extracts: Effects of raw material and production method on antioxidant effectiveness and reduction of DNA damage in caco-2 cells. J. Agric. Food Chem. 2010, 58, 6636–6642. [Google Scholar] [CrossRef] [PubMed]
  48. Tan, A.C.; Konczak, I.; Ramzan, I.; Sze, D.M. Native australian fruit polyphenols inhibit cell viability and induce apoptosis in human cancer cell lines. Nutr. Cancer 2011, 63, 444–455. [Google Scholar] [CrossRef] [PubMed]
  49. Botden, I.P.; Oeseburg, H.; Durik, M.; Leijten, F.P.; Van Vark-Van Der Zee, L.C.; Musterd-Bhaggoe, U.M.; Garrelds, I.M.; Seynhaeve, A.L.; Langendonk, J.G.; Sijbrands, E.J.; et al. Red wine extract protects against oxidative-stress-induced endothelial senescence. Clin. Sci. 2012, 123, 499–507. [Google Scholar] [CrossRef] [PubMed]
  50. Yalcin, C.O.; Aliyazicioglu, Y.; Demir, S.; Turan, I.; Bahat, Z.; Misir, S.; Deger, O. Evaluation of the radioprotective effect of turkish propolis on foreskin fibroblast cells. J. Cancer Res. Ther. 2016, 12, 990–994. [Google Scholar] [PubMed]
  51. Tsai, Y.C.; Wang, Y.H.; Liou, C.C.; Lin, Y.C.; Huang, H.; Liu, Y.C. Induction of oxidative DNA damage by flavonoids of propolis: Its mechanism and implication about antioxidant capacity. Chem. Res. Toxicol. 2012, 25, 191–196. [Google Scholar] [CrossRef] [PubMed]
  52. Nguyen, M.M.; Ahmann, F.R.; Nagle, R.B.; Hsu, C.H.; Tangrea, J.A.; Parnes, H.L.; Sokoloff, M.H.; Gretzer, M.B.; Chow, H.H. Randomized, double-blind, placebo-controlled trial of polyphenon e in prostate cancer patients before prostatectomy: Evaluation of potential chemopreventive activities. Cancer Prev. Res. 2012, 5, 290–298. [Google Scholar] [CrossRef] [PubMed]
  53. Ferk, F.; Misik, M.; Nersesyan, A.; Pichler, C.; Jager, W.; Szekeres, T.; Marculescu, R.; Poulsen, H.E.; Henriksen, T.; Bono, R.; et al. Impact of xanthohumol (a prenylated flavonoid from hops) on DNA stability and other health-related biochemical parameters: Results of human intervention trials. Mol. Nutr. Food Res. 2016, 60, 773–786. [Google Scholar] [CrossRef] [PubMed]
  54. Cariddi, L.N.; Sabini, M.C.; Escobar, F.M.; Montironi, I.; Manas, F.; Iglesias, D.; Comini, L.R.; Sabini, L.I.; Dalcero, A.M. Polyphenols as possible bioprotectors against cytotoxicity and DNA damage induced by ochratoxin A. Environ. Toxicol. Pharmacol. 2015, 39, 1008–1018. [Google Scholar] [CrossRef] [PubMed]
  55. Papiez, M.A. The influence of curcumin and (−)-epicatechin on the genotoxicity and myelosuppression induced by etoposide in bone marrow cells of male rats. Drug Chem. Toxicol. 2013, 36, 93–101. [Google Scholar] [CrossRef] [PubMed]
  56. Rehman, M.U.; Tahir, M.; Ali, F.; Qamar, W.; Lateef, A.; Khan, R.; Quaiyoom, A.; Oday, O.H.; Sultana, S. Cyclophosphamide-induced nephrotoxicity, genotoxicity, and damage in kidney genomic DNA of swiss albino mice: The protective effect of ellagic acid. Mol. Cell. Biochem. 2012, 365, 119–127. [Google Scholar] [CrossRef] [PubMed]
  57. Srivastava, A.K.; Bhatnagar, P.; Singh, M.; Mishra, S.; Kumar, P.; Shukla, Y.; Gupta, K.C. Synthesis of plga nanoparticles of tea polyphenols and their strong in vivo protective effect against chemically induced DNA damage. Int. J. Nanomed. 2013, 8, 1451–1462. [Google Scholar]
  58. Li, G.X.; Chen, Y.K.; Hou, Z.; Xiao, H.; Jin, H.; Lu, G.; Lee, M.J.; Liu, B.; Guan, F.; Yang, Z.; et al. Pro-oxidative activities and dose-response relationship of (−)-epigallocatechin-3-gallate in the inhibition of lung cancer cell growth: A comparative study in vivo and in vitro. Carcinogenesis 2010, 31, 902–910. [Google Scholar] [CrossRef] [PubMed]
  59. Marrazzo, G.; Bosco, P.; La Delia, F.; Scapagnini, G.; Di Giacomo, C.; Malaguarnera, M.; Galvano, F.; Nicolosi, A.; Li Volti, G. Neuroprotective effect of silibinin in diabetic mice. Neurosci. Lett. 2011, 504, 252–256. [Google Scholar] [CrossRef] [PubMed]
  60. Rocha de Oliveira, C.; Ceolin, J.; Rocha de Oliveira, R.; Goncalves Schemitt, E.; Raskopf Colares, J.; De Freitas Bauermann, L.; Hilda Costabeber, I.; Morgan-Martins, M.I.; Mauriz, J.L.; Da Silva, J.; et al. Effects of quercetin on polychlorinated biphenyls-induced liver injury in rats. Nutr. Hosp. 2014, 29, 1141–1148. [Google Scholar] [PubMed]
  61. Patil, S.L.; Rao, N.B.; Somashekarappa, H.M.; Rajashekhar, K.P. Antigenotoxic potential of rutin and quercetin in swiss mice exposed to gamma radiation. Biomed. J. 2014, 37, 305–313. [Google Scholar] [CrossRef] [PubMed]
  62. Manzolli, E.S.; Serpeloni, J.M.; Grotto, D. Protective effects of the flavonoid chrysin against methylmercury-induced genotoxicity and alterations of antioxidant status, in vivo. Oxidative Med. Cell. Longev. 2015, 2015, 602360. [Google Scholar] [CrossRef] [PubMed]
  63. Ma, J.Q.; Ding, J.; Xiao, Z.H.; Liu, C.M. Puerarin ameliorates carbon tetrachloride-induced oxidative DNA damage and inflammation in mouse kidney through erk/nrf2/are pathway. Food Chem. Toxicol. 2014, 71, 264–271. [Google Scholar] [CrossRef] [PubMed]
  64. Liu, C.M.; Ma, J.Q.; Sun, Y.Z. Quercetin protects the rat kidney against oxidative stress-mediated DNA damage and apoptosis induced by lead. Environ. Toxicol. Pharmacol. 2010, 30, 264–271. [Google Scholar] [CrossRef] [PubMed]
  65. Hobbs, C.A.; Swartz, C.; Maronpot, R.; Davis, J.; Recio, L.; Koyanagi, M.; Hayashi, S.M. Genotoxicity evaluation of the flavonoid, myricitrin, and its aglycone, myricetin. Food Chem. Toxicol. 2015, 83, 283–292. [Google Scholar] [CrossRef] [PubMed]
  66. Gupta, C.; Vikram, A.; Tripathi, D.N.; Ramarao, P.; Jena, G.B. Antioxidant and antimutagenic effect of quercetin against den induced hepatotoxicity in rat. Phytother. Res. 2010, 24, 119–128. [Google Scholar] [CrossRef] [PubMed]
  67. Ansar, S.; Siddiqi, N.J.; Zargar, S.; Ganaie, M.A.; Abudawood, M. Hepatoprotective effect of quercetin supplementation against acrylamide-induced DNA damage in wistar rats. BMC Complement. Altern. Med. 2016, 16, 327. [Google Scholar] [CrossRef] [PubMed]
  68. Carino-Cortes, R.; Alvarez-Gonzalez, I.; Martino-Roaro, L.; Madrigal-Bujaidar, E. Effect of naringin on the DNA damage induced by daunorubicin in mouse hepatocytes and cardiocytes. Biol. Pharm. Bull. 2010, 33, 697–701. [Google Scholar] [CrossRef] [PubMed]
  69. Das, S.; Das, J.; Paul, A.; Samadder, A.; Khuda-Bukhsh, A.R. Apigenin, a bioactive flavonoid from lycopodium clavatum, stimulates nucleotide excision repair genes to protect skin keratinocytes from ultraviolet b-induced reactive oxygen species and DNA damage. J. Acupunct. Meridian Stud. 2013, 6, 252–262. [Google Scholar] [CrossRef] [PubMed]
  70. Cha, J.W.; Piao, M.J.; Kim, K.C.; Yao, C.W.; Zheng, J.; Kim, S.M.; Hyun, C.L.; Ahn, Y.S.; Hyun, J.W. The polyphenol chlorogenic acid attenuates uvb-mediated oxidative stress in human hacat keratinocytes. Biomol. Ther. 2014, 22, 136–142. [Google Scholar] [CrossRef] [PubMed]
  71. Burgos-Moron, E.; Calderon-Montano, J.M.; Orta, M.L.; Pastor, N.; Perez-Guerrero, C.; Austin, C.; Mateos, S.; Lopez-Lazaro, M. The coffee constituent chlorogenic acid induces cellular DNA damage and formation of topoisomerase i- and ii-DNA complexes in cells. J. Agric. Food Chem. 2012, 60, 7384–7391. [Google Scholar] [CrossRef] [PubMed]
  72. Hasegawa, T.; Shimada, S.; Ishida, H.; Nakashima, M. Chafuroside b, an oolong tea polyphenol, ameliorates uvb-induced DNA damage and generation of photo-immunosuppression related mediators in human keratinocytes. PLoS ONE 2013, 8, e77308. [Google Scholar] [CrossRef] [PubMed]
  73. Vanella, L.; Barbagallo, I.; Acquaviva, R.; Di Giacomo, C.; Cardile, V.; Abraham, N.G.; Sorrenti, V. Ellagic acid: Cytodifferentiating and antiproliferative effects in human prostatic cancer cell lines. Curr. Pharm. Des. 2013, 19, 2728–2736. [Google Scholar] [CrossRef] [PubMed]
  74. Abib, R.T.; Quincozes-Santos, A.; Zanotto, C.; Zeidan-Chulia, F.; Lunardi, P.S.; Goncalves, C.A.; Gottfried, C. Genoprotective effects of the green tea-derived polyphenol/epicatechin gallate in c6 astroglial cells. J. Med. Food 2010, 13, 1111–1115. [Google Scholar] [CrossRef] [PubMed]
  75. Miene, C.; Weise, A.; Glei, M. Impact of polyphenol metabolites produced by colonic microbiota on expression of cox-2 and gstt2 in human colon cells (lt97). Nutr. Cancer 2011, 63, 653–662. [Google Scholar] [CrossRef] [PubMed]
  76. Hossain, M.Z.; Patel, K.; Kern, S.E. Salivary alpha-amylase, serum albumin, and myoglobin protect against DNA-damaging activities of ingested dietary agents in vitro. Food Chem. Toxicol. 2014, 70, 114–119. [Google Scholar] [CrossRef] [PubMed]
  77. Mohan, S.; Thiagarajan, K.; Chandrasekaran, R. In vitro evaluation of antiproliferative effect of ethyl gallate against human oral squamous carcinoma cell line kb. Nat. Prod. Res. 2015, 29, 366–369. [Google Scholar] [CrossRef] [PubMed]
  78. Zielinska-Przyjemska, M.; Ignatowicz, E.; Krajka-Kuzniak, V.; Baer-Dubowska, W. Effect of tannic acid, resveratrol and its derivatives, on oxidative damage and apoptosis in human neutrophils. Food Chem. Toxicol. 2015, 84, 37–46. [Google Scholar] [CrossRef] [PubMed]
  79. Kumar, D.; Basu, S.; Parija, L.; Rout, D.; Manna, S.; Dandapat, J.; Debata, P.R. Curcumin and ellagic acid synergistically induce ros generation, DNA damage, p53 accumulation and apoptosis in hela cervical carcinoma cells. Biomed. Pharmacother. 2016, 81, 31–37. [Google Scholar] [CrossRef] [PubMed]
  80. Sebastia, N.; Montoro, A.; Hervas, D.; Pantelias, G.; Hatzi, V.I.; Soriano, J.M.; Villaescusa, J.I.; Terzoudi, G.I. Curcumin and trans-resveratrol exert cell cycle-dependent radioprotective or radiosensitizing effects as elucidated by the pcc and g2-assay. Mutat. Res. 2014, 766–767, 49–55. [Google Scholar] [CrossRef] [PubMed]
  81. Lewinska, A.; Wnuk, M.; Grabowska, W.; Zabek, T.; Semik, E.; Sikora, E.; Bielak-Zmijewska, A. Curcumin induces oxidation-dependent cell cycle arrest mediated by sirt7 inhibition of rdna transcription in human aortic smooth muscle cells. Toxicol. Lett. 2015, 233, 227–238. [Google Scholar] [CrossRef] [PubMed]
  82. Sun, B.; Ross, S.M.; Trask, O.J.; Carmichael, P.L.; Dent, M.; White, A.; Andersen, M.E.; Clewell, R.A. Assessing dose-dependent differences in DNA-damage, p53 response and genotoxicity for quercetin and curcumin. Toxicol. In Vitro 2013, 27, 1877–1887. [Google Scholar] [CrossRef] [PubMed]
  83. Ide, H.; Yu, J.; Lu, Y.; China, T.; Kumamoto, T.; Koseki, T.; Muto, S.; Horie, S. Testosterone augments polyphenol-induced DNA damage response in prostate cancer cell line, LNCaP. Cancer Sci. 2011, 102, 468–471. [Google Scholar] [CrossRef] [PubMed]
  84. Seo, Y.N.; Lee, M.Y. Inhibitory effect of antioxidants on the benz[a]anthracene-induced oxidative DNA damage in lymphocyte. J. Environ. Biol./Acad. Environ. Biol. India 2011, 32, 7–10. [Google Scholar]
  85. Lu, J.J.; Cai, Y.J.; Ding, J. Curcumin induces DNA damage and caffeine-insensitive cell cycle arrest in colorectal carcinoma hct116 cells. Mol. Cell. Biochem. 2011, 354, 247–252. [Google Scholar] [CrossRef] [PubMed]
  86. Lu, J.J.; Cai, Y.J.; Ding, J. The short-time treatment with curcumin sufficiently decreases cell viability, induces apoptosis and copper enhances these effects in multidrug-resistant k562/a02 cells. Mol. Cell. Biochem. 2012, 360, 253–260. [Google Scholar] [CrossRef] [PubMed]
  87. Turkez, H.; Sisman, T. The genoprotective activity of resveratrol on aflatoxin b(1)-induced DNA damage in human lymphocytes in vitro. Toxicol. Ind. Health 2012, 28, 474–480. [Google Scholar] [CrossRef] [PubMed]
  88. Chen, C.; Jiang, X.; Hu, Y.; Zhang, Z. The protective role of resveratrol in the sodium arsenite-induced oxidative damage via modulation of intracellular gsh homeostasis. Biol. Trace Element Res. 2013, 155, 119–131. [Google Scholar] [CrossRef] [PubMed]
  89. Demoulin, B.; Hermant, M.; Castrogiovanni, C.; Staudt, C.; Dumont, P. Resveratrol induces DNA damage in colon cancer cells by poisoning topoisomerase ii and activates the atm kinase to trigger p53-dependent apoptosis. Toxicol. In Vitro 2015, 29, 1156–1165. [Google Scholar] [CrossRef] [PubMed]
  90. Rashid, A.; Liu, C.; Sanli, T.; Tsiani, E.; Singh, G.; Bristow, R.G.; Dayes, I.; Lukka, H.; Wright, J.; Tsakiridis, T. Resveratrol enhances prostate cancer cell response to ionizing radiation. Modulation of the ampk, akt and mtor pathways. Radiat. Oncol. 2011, 6, 669–672. [Google Scholar] [CrossRef] [PubMed]
  91. Gonthier, B.; Allibe, N.; Cottet-Rousselle, C.; Lamarche, F.; Nuiry, L.; Barret, L. Specific conditions for resveratrol neuroprotection against ethanol-induced toxicity. J. Toxicol. 2012, 2012, 973134. [Google Scholar] [CrossRef] [PubMed]
  92. Yilmaz, D.; Aydemir, N.C.; Vatan, O.; Tuzun, E.; Bilaloglu, R. Influence of naringin on cadmium-induced genomic damage in human lymphocytes in vitro. Toxicol. Ind. Health 2012, 28, 114–121. [Google Scholar] [CrossRef] [PubMed]
  93. Cristina Marcarini, J.; Ferreira Tsuboy, M.S.; Cabral Luiz, R.; Regina Ribeiro, L.; Beatriz Hoffmann-Campo, C.; Segio Mantovani, M. Investigation of cytotoxic, apoptosis-inducing, genotoxic and protective effects of the flavonoid rutin in htc hepatic cells. Exp. Toxicol. Pathol. 2011, 63, 459–465. [Google Scholar] [CrossRef] [PubMed]
  94. Maeda, J.; Roybal, E.J.; Brents, C.A.; Uesaka, M.; Aizawa, Y.; Kato, T.A. Natural and glucosyl flavonoids inhibit poly(adp-ribose) polymerase activity and induce synthetic lethality in brca mutant cells. Oncol. Rep. 2014, 31, 551–556. [Google Scholar] [PubMed]
  95. Wu, L.Y.; Lu, H.F.; Chou, Y.C.; Shih, Y.L.; Bau, D.T.; Chen, J.C.; Hsu, S.C.; Chung, J.G. Kaempferol induces DNA damage and inhibits DNA repair associated protein expressions in human promyelocytic leukemia hl-60 cells. Am. J. Chin. Med. 2015, 43, 365–382. [Google Scholar] [CrossRef] [PubMed]
  96. Kurzawa-Zegota, M.; Najafzadeh, M.; Baumgartner, A.; Anderson, D. The protective effect of the flavonoids on food-mutagen-induced DNA damage in peripheral blood lymphocytes from colon cancer patients. Food Chem. Toxicol. 2012, 50, 124–129. [Google Scholar] [CrossRef] [PubMed]
  97. Kozics, K.; Valovicova, Z.; Slamenova, D. Structure of flavonoids influences the degree inhibition of benzo(a)pyrene—Induced DNA damage and micronuclei in hepg2 cells. Neoplasma 2011, 58, 516–524. [Google Scholar] [CrossRef] [PubMed]
  98. Kim, J.Y.; Jeon, Y.K.; Jeon, W.; Nam, M.J. Fisetin induces apoptosis in huh-7 cells via downregulation of birc8 and bcl2l2. Food Chem. Toxicol. 2010, 48, 2259–2264. [Google Scholar] [CrossRef] [PubMed]
  99. Huang, W.W.; Chiu, Y.J.; Fan, M.J.; Lu, H.F.; Yeh, H.F.; Li, K.H.; Chen, P.Y.; Chung, J.G.; Yang, J.S. Kaempferol induced apoptosis via endoplasmic reticulum stress and mitochondria-dependent pathway in human osteosarcoma u-2 os cells. Mol. Nutr. Food Res. 2010, 54, 1585–1595. [Google Scholar] [CrossRef] [PubMed]
  100. Barcelos, G.R.; Grotto, D.; Angeli, J.P.; Serpeloni, J.M.; Rocha, B.A.; Bastos, J.K.; Barbosa, F., Jr. Evaluation of antigenotoxic effects of plant flavonoids quercetin and rutin on hepg2 cells. Phytother. Res. 2011, 25, 1381–1388. [Google Scholar] [CrossRef] [PubMed]
  101. Barcelos, G.R.; Angeli, J.P.; Serpeloni, J.M.; Grotto, D.; Rocha, B.A.; Bastos, J.K.; Knasmuller, S.; Junior, F.B. Quercetin protects human-derived liver cells against mercury-induced DNA-damage and alterations of the redox status. Mutat. Res. 2011, 726, 109–115. [Google Scholar] [CrossRef] [PubMed]
  102. Ding, M.; Zhao, J.; Bowman, L.; Lu, Y.; Shi, X. Inhibition of ap-1 and mapk signaling and activation of nrf2/are pathway by quercitrin. Int. J. Oncol. 2010, 36, 59–67. [Google Scholar] [CrossRef] [PubMed]
  103. Duthie, S.J.; Johnson, W.; Dobson, V.L. The effect of dietary flavonoids on DNA damage (strand breaks and oxidised pyrimdines) and growth in human cells. Mutat. Res. 1997, 390, 141–151. [Google Scholar] [CrossRef]
  104. Duthie, S.J.; Collins, A.R.; Duthie, G.G.; Dobson, V.L. Quercetin and myricetin protect against hydrogen peroxide-induced DNA damage (strand breaks and oxidised pyrimidines) in human lymphocytes. Mutat. Res. 1997, 393, 223–231. [Google Scholar] [CrossRef]
Table 1. Effects of whole foods or drinks on various genetic damage endpoints, in humans, in animals (‘in vivo’), and in cultured cells (‘in vitro’).
Table 1. Effects of whole foods or drinks on various genetic damage endpoints, in humans, in animals (‘in vivo’), and in cultured cells (‘in vitro’).
ReferenceMaterial TestedAnalysisAssaysSystemConcentration/DoseResult
In Humans
[10]Orange juicePolyphenols8-OH–G in urine by ELISAOverweight/obese humans300 or 745 mg/day (12 weeks)8-OH–G ↓
[11]Aronia-citrus juiceFlavonones, flavones, antocyanins etc.8-OH–G in plasma by UHPLC-MS/MSTriathletes (supplemented and placebo groups)200 mL/day (45 days)Inconclusive—levels of DNA damage products too low
[12]Dark chocolatePolyphenolsComet assayHealthy subjects: PBMN cells860 mg/day (2 weeks)H2O2-induced SBs ↓ (short-term—2 h—only)
[13]De-alcoholised wineAnthocyanins, flavonols etc.Comet assay with FpgPost-menopausal women; peripheral blood lymphocytes500 mL/day (1 month)No effect
[14]Wild blueberry drinkPhenolic acids and anthocyaninsComet assay + Fpg; H2O2resistance (comet assay); DNA repair (in vitro comet assay)Subjects with cardiovascular risk factors: PBMN cells375 mg anthocyanins/day (6 weeks)No effect on DNA SBs. Fpg-sensitive sites ↓; H2O2 resistance ↑; no effect on repair
[15]Green tea Comet assayHealthy subjects: PBMN cells 30, 60, 90 min after ingestion, exposed ex vivo to UV(A)/VIS radiationSingle 540 mL doseProtection against UV(A)/VIS-induced DNA SBs seen in ‘responders’
[16]HoneyPhenolic compoundsComet assay with EndoIII, FpgPesticide-exposed humans2-week honey supplementation (50 g/day)DNA repair ↑, EndoIII and Fpg sites ↓
In Vivo
[17]Chrysobalanus icaco fruitPolyphenols, Mg, SeComet assay on blood and MN assay on bone marrow and PBMNRats + DoxUp to 0.4 g/kg/day for 14 daysBlood cells; DNA SBs ↓. Bone marrow, blood cells; MN ↓
[18]Green and black teas 8-OH–G on liver by HPLCSwiss albino mice + Na arsenite2.5% of 0.5 g dry leaves/5 mL of boiled water (equivalent to human consumption of 1 cup). 22 days.Protection (8-OH–G ↓)
[19]Piquia pulpPhenolic compounds, carotenoidsComet assay on liver, kidney, heart cells MN on bone marrow and PBMN cellsRats + Dox75, 150, 300 mg/kg/day for 14 daysProtection against DNA SBs and MN formation: lowest dose tends to be most effective
[20]Açai pulpPhenolic compounds, carotenoidsComet assay on liver, kidney and PBMN cells: MN on bone marrow and PBMN cellsMice + Dox3.33,10, 16.7 g/kg/day for 1 or 14 daysProtection against DNA SBs and MN formation: 14 days pretreatment more effective
[21]Cloudy apple juicePolyphenolsComet assay on liver cellsRats10 mL/kg/day for 28 daysDNA SBs ↑ and no effect on N-nitrosodiethylamine-induced damage
[22]Green tea--Comet assay on intestinal cellsRats + As10 mg/mL in water for 28 daysClaim protection
[23]SpinachTotal polyphenolsComet assay on leukocytesHyperlipidemic rats5% (powder) in diet, for 6 weeksH2O2-induced DNA SBs in leukocytes ↓
In Vitro
[24]Green tea--Comet assay with FpgHuman PBMN cells7–71 µM catechinsDNA damage ↓ at lower concentrations but ↑ at highest concentration
[25]Herbal preparationTotal phenolicsComet assayYAC-1 (mouse lymphoma) cells1–13 mg/mLDNA SBs ↑ at 8.7 mg/mL
Rat fibroblasts1–13 mg/mLDNA SBs ↑ at 2.2 mg/mL
[26]Various honeys--Comet assayHepG2 (human liver carcinoma) cells treated with B(a)P, PhIP, nitrosamines0.1–100 mg/mLSlight decreases in DNA SBs in most cases, not dose-dependent
PBMN: peripheral blood mononuclear; SB: strand break; Fpg: formamidopyrimidine DNA glycosylase; UV: ultraviolet; VIS: visible; MN: micronucleus/micronuclei; Dox: doxorubicin; EndoIII: endonuclease III (Nth); 8-OH–G: 8-oxo–7,8-dihydroguanine; B(a)P: benzo(a)pyrene; PhIP: 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine.
Table 2. Effects of plant extracts on various genetic damage endpoints, in humans, in animals (‘in vivo’), and in cultured cells (‘in vitro’).
Table 2. Effects of plant extracts on various genetic damage endpoints, in humans, in animals (‘in vivo’), and in cultured cells (‘in vitro’).
ReferenceMaterial testedAnalysisAssaysSystemConcentration/DoseResult
In Humans
[27]Green tea polyphenols Urinary 8-OH–G by HPLCPostmenopausal women with osteoporosis500 mg/day (capsules, 6 months)8-OH–G ↓ over 6 months
In Vivo
Tea-Related
[28]Green tea polyphenols 8-OH–G in brain by Ab assayRats400 mg/day (gastric intubation, 4 weeks)8-OH–G ↓
[29]Green tea polyphenolsEpicatechin derivativesCPD on skin and lymph nodes by Ab assayMice (NER+ and-) + UV0.2% in drinking water (7 days before UV irradiation)Enhanced removal of CPDs in NER-proficient mice
[30]Green tea extract MN in polychromatic erythrocytesMice + Cr(VI)30 mg/kg (one dose—gavage)MN ↓
[31]Green tea polyphenols Comet assay with Fpg on blood; 8-OH–G in brain by HPLCRats + acrylonitrile0.4% in diet (1 week before acrylonitrile and then throughout acrylonitrile treatment for 28 days)↓ Fpg-sensitive sites and 8-OH–G ↓
[32]Calluna vulgaris polyphenol extract CPDs in skin by Ab assayMice + UV(B)4 mg/cm2 (30 min before exposure to UV, repeated on 10 days)CPDs ↓
[33]Podophyllum hexandrum extractTotal phenolicsAlkaline halo assay; DNA repair (SB rejoining—PCR assay)Thymocytes from γ-irradiated mice15 mg/kg (one dose, i.p.)Protection against γ-ray-induced DNA SBs and accelerated rejoining
[34]Cotinus coggyria extract Comet assay on liverRats + pyrogallol0.5–2 g/kg (single dose, i.p.)SBs at highest dose of extract alone: protection against pyrogallol-induced SBs at 0.5 g/kg
In Vitro
Tea-Related
[35]Green tea polyphenols Comet assayMelanoma cell lines20–60 μg/mL (time)40, 60 μg/mL; DNA SBs ↑
[36]Green tea extract Comet assayHuman laryngeal carcinoma cell line (HEp2) + drug-resistant cell line CK21× = 2 g/200 mL H2O2 Concentration tested = 0.1×SBs ↑ at 72 h, not 48 h
Lamiaceae
[37]Citrus and rosemary bioflavonoid extractTotal polyphenolsComet assayHaCaT (human keratinocytes) + UV(B)100 μg/mLPre-treatment: UV(B)-induced DNA SBs ↓
MNHuman lymphocytes + X-ray1 mg/mLX-ray induced MN ↓
[38]Thymus vulgaris extract Comet assay and γ-H2AX by AbHuman skin model exposed to UV(B)1.8 μg/mLProtection against DNA damage
[39]Thymus vulgaris extract Comet assay 24 h after UVNCTC (human keratinocytes) + UV(A) or UV(B)1.82 μg/mLDNA SBs ↓
MNNo effect seen
γ-H2AX by AbNo effect seen
[40]Lemon balm extractPolyphenolsComet assay and γ-H2AX by Ab assayHuman keratinocytes + UV(B)15–100 μg/mLDNA SBs ↓ (100 μg/mL); γH2AX ↓ (15 μg/mL)
[41]Ocimum sanctum extract (“Holy basil”)Total phenolicsComet assaySH-SY5Y (human neuroblastoma) cells75 μg/mLH2O2-induced DNA SBs ↓
[42]Various Lamiaceae leaf extractsTotal polyphenols, flavonoidsComet assayHepG2 (human liver carcinoma) cells + CdCl250–350 μg/mL for 4 hDose-dependent decrease in Cd-induced DNA SBs
Fruits and Berries
[43]Strawberry extractAnthocyaninsComet assayHuman dermal fibroblasts exposed to UV(A)0.05–0.5 mg/mLProtection against DNA SBs at 0.25, 0.5 mg/mL
[44]Strawberry extractTotal phenolics, flavonoids, anthocyanins, vitamin C, β-caroteneComet assayHuman dermal fibroblasts exposed to H2O20.5 mg/mLDNA SBs ↓
[45]Vaccinium berries extractTotal polyphenols and anthocyaninsComet assayA549 (human lung adenocarcinoma) cells21–167 μg/mLDose-dependent protection against DNA SBs induced by t-BOOH
[46]Blackcurrant extract Comet assay (H2O2 resistance)TK6 (human lymphoblastoid) cells0.5–3 mg/mLH2O2-induced DNA SBs ↓
MN ± H2O21 mg/mLH2O2-induced MN ↓
[47]Various apple polyphenol s extractMonomeric polyphenols oligosaccharides and oligomeric procyanidins.Comet assay with FpgCaco2 (colon carcinoma) cells1–100 μg/mLMenadione-induced DNA SBs and Fpg-sensitive sites ↓ Greatest protection at low concentrations; with some extracts, damage ↑ at high doses
[48]Polyphenol extracts of Australian fruitsPhenolic acids and anthocyaninsMNHT29 (human colon adenocarcinoma) cells0.5–1 mg/mLMN ↑ with one extract
[49]Red wine extract Comet assayHUVECs (human umbilical vein endothelial) cells + t-BOOH25 μg/mLDNA SBs ↓
Honey-Related
[16]Honey extractPhenolic compoundsComet assay with EndoIII, FpgBronchial epithelial and neuronal cells5 μg/mLPesticide (glyphosate, chlorpyrifos)-induced damage (SBs, EndoIII and Fpg sites) ↓
Cellular DNA repairProtection against inhibition of repair of DNA SBs by pesticides
[50]Propolis extr Comet assayFibroblasts0.1–0.3 mg/mLγ-Ray-induced DNA SBs ↓
[51]Propolis Comet assay + Fpg, EndoIIIHuman gastric cancer cell line AGS0.3 µg/mLHigh DNA damage, suppressed by antioxidants or catalase
Ab: antibody; CPD: cyclobutane pyrimidine dimer; NER: nucleotide excision repair; i.p.: intraperitoneal; t-BOOH: tert-butyl hydroperoxide; HUVEC: human umbilical vein endothelial cell.
Table 3. Effects of individual polyphenolic compounds on various genetic damage endpoints, in humans, in animals (‘in vivo’), and in cultured cells (‘in vitro’).
Table 3. Effects of individual polyphenolic compounds on various genetic damage endpoints, in humans, in animals (‘in vivo’), and in cultured cells (‘in vitro’).
ReferenceMaterial TestedAssaysSystemConcentration/DoseResult
In Humans
[52]Epigallocatechin gallate8-OH–G in leukocyte DNA (HPLC/UV/MS)Prostate cancer patients800 mg/day (3 to 6 weeks before surgery)Decrease in 8-OH–G not significant
[53]Xanthohumol (drink)Comet assay and urinary 8-OH–G (UPLC)Cross over intervention trial, healthy subjects12 mg/day for 14 daysFPG-sites ↓, H2O2-induced SBs ↓, 8-OH–G ↓
Xanthohumol (pills)Comet assayParallel intervention trial, healthy subjectsFPG-sites ↓, H2O2-induced SBs ↓
In Vivo
[54]LuteolinComet assay and MN on blood and bone marrowMice + ochratoxin A2.5 mg/kg (one dose i.p.)No effect
Chlorogenic acid10 mg/kg (one dose i.p.)DNA SBs ↓; also MN ↓
Caffeic acid10 mg/kg (one dose i.p.)DNA SBs ↓
[55]CurcuminComet assay with FPG on bone marrowRats + etoposide100 or 200 mg/kg/day (7 days, gavage)Pretreatment → etoposide-induced DNA damage ↓
Epicatechin20 or 40 mg/kg/day (7 days, gavage)Pretreatment → etoposide-induced oxidative DNA damage ↓ (less than with Curcumin) but not DNA SBs.
[56]Ellagic acidMN in polychromatic erythrocytes; alkaline unwindingSwiss albino mice + cyclophosphamide50/100 mg/kg/day (orally, 7 days)Protection against MN formation and DNA SBs
[57]Epigallocatechin gallate and theaflavinAlkaline unwinding assayMouse skin + dimethylbenzanthracene100 μg/mouse (topical application, 1 h)Topical pretreatment → DNA SBs ↓
Epigallocatechin gallate and theaflavin as NPs (PLGA)5–20 μg/mouse (topical application, 1 h)NP form has ~30-fold dose-advantage
[58]Epigallocatechin gallateγ-H2AX by Western blot and Ab and 8-OH–G by Ab assayH1299 (human lung cancer cells) xenografts in mice0.1%–0.5% in diet, 30 mg/kg/day injectionDose-dependent ↑ in γ-H2AX and 8-OH–G
[59]Silibinin8-OH–G in various brain regions by ELISADiabetic mice20 mg/kg/day i.p. (4 weeks)8-OH–G ↓ in different regions of brain
[60]QuercetinMN in bone marrow and bloodRats + PCBs50 mg/kg/day for 25 daysPCB-induced MN ↓
[61]QuercetinChrom abs and MN in bone marrow; Comet assay on bloodMice + γ-irradiation20 mg/kg/day for 5 daysRadiation-induced Chrom abs, SBs, MN ↓
Rutin10 mg/kg/day for 5 days
[62]ChrysinComet assay (hepatocytes and leukocytes)Rats + methyl mercury0.1, 1, 10 mg/kg/day for 45 daysMeHg-induced SBs ↓ at higher doses
[63]Puerarin8-OH–G in kidney by HPLCMice + CCl40.2 or 0.4 g/kg/day for 4 weeks8-OH–G ↓
[64]Quercetin8-OH–G in kidney by HPLCRats + lead10 mg/kg/day for 10 weeks8-OH–G ↓
[65]Myricitrin, MyricetinMN (reticulocytes); Comet assay (liver, duodenum, stomach)Mice1, 1.5, 2 g/kg/day for 3 daysNo increase in MN, SBs only in liver + myricetin
[66]QuercetinComet assay on liverRats + DEN10, 30, 100 mg/kg/day for 5 daysDEN-induced SBs ↓
[34]MyricetinComet assay on liverRats + pyrogallol255.5 μg/kg 2 h and 12 h before pyrogallolSBs ↓ in liver
[67]QuercitinComet assay on liverRats + acrylamide10 mg/kg/day for 5 daysNo effect of quercetin alone. Acrylamide-induced SBs ↓
8-OH–G in liver by ELISANo effect of quercetin alone. Acrylamide-induced 8-OH–G ↓
[68]NaringinComet assayMice (hepatocytes and cardiocytes)50, 250 or 500 mg/kg oral (one dose)No effect
50, 250 or 500 mg/kg oral (one dose) + Dau i.p.DNA SBs induced by Dau ↓
[69]ApigeninChrom abs and MN in bone marrow; comet assay on skin; DNA repair (removal of CPDs by Ab)Mice + UV(B)1.5–3 mg/cm2 (24 h; during UV irradiation)Chrom abs and MN ↓; tail length ↓. Removal of dimers apparently stimulated by apigenin
In Vitro
Tea-Related
[70]Chlorogenic acidComet assayHaCaT (human keratinocytes) cells + UV(B)Not stated. Probably 5–80 μMDNA SBs ↓
[71]Chlorogenic acidComet assayK562 (human leukaemia) cells0.5–5 mMDNA SBs ↑
γ-H2AX by AbChinese hamster AA8 cell line and K5620.5 mMγ-H2AX foci ↑
[72]Chafuroside B (tea polyphenol)CPDs by AbHuman keratinocytes + UV(B)1 μMCPDs ↓ after 24 h
[73]Ellagic acidComet assayProstate cancer cell lines LNCaP, DU145, BPH-14.5–300 μMDNA SBs ↑ at 9 μM in BPH-1, 37 μM in DU 145, 150 μM in LnCap
[74]Epicatechin gallateComet assay; MNC6 astroglial cells0.1–1 μMH2O2-induced DNA SBs and MN formation ↓
[58]Epigallocatechin gallateγ-H2AX and 8-OH–G by Ab assayH1299 (human lung adenocarcinoma) cells50 μMγ-H2AX and 8-OH–G ↑
[75]Metabolites of quercetin, chlorogenic acidComet assayLT97 (human colorectal adenoma) cells + cumene hydroperoxide2.5 μM/5 μMDecrease in DNA SBs
[76]Epigallocatechin gallateComet assayHeLa (human cervical cancer) cells, p53R (cells with p53 reporter)10, 20 μg/mLDNA SBs ↑
[77]Ethyl gallateComet assayHuman carcinoma cell line KB20–50 μg/mLDNA SBs ↑
[78]Tannic acidComet assay with FpgHuman neutrophils10–150 μMDNA SBs ↑ (dose-dependent); weak effect (↑) in TPA-stimulated cells. Fpg sites also ↑, but ↓ in TPA-stimulated cells
ResveratrolDNA damage (SBs) ↑ (dose-dependent); but ↓ (dose-dependent) in TPA-stimulated cells. Same pattern with FPG sites
[36]Epigallocatechin gallate; Epicatechin gallateComet assayHEp2 (human laryngeal carcinoma cell line)50 μMWith either ECG or EGCG, SBs ↓ at 48 h (from background); no effect at 72 h
CK2 (drug resistant, from HEp2)No effect at 48 or 72 h
Curcumin
[79]Curcumin; Ellagic acidComet assayHeLa (human cervical cancer) cells25 μMDNA SBs ↑ (with both together; not significant alone)
[80];CurcuminChrom abs and PCCHuman lymphocytes, with/without stimulation0.14–7 μMRadioprotective effects seen for both reagents in PCC assay (non-cycling cells)
Radiosensitisation of cycling cells (chrom abs) by both reagents
Resveratrol2.2–220 μM
[81]Curcumin8-OH–G by Ab assaySmooth muscle cellsup to 10 μM8-OH–G ↑
[82]Quercetin; Curcuminγ-H2AX by Ab assayHT1080 human fibrosarcoma cell line30 and 80 μM Quercetin; 10 and 15 μM Curcumin,Significant increases in γ H2AX
MN30 μM Quercetin; 10 μM CurcuminSignificant increases in MN. (Quercetin less effective.)
[83]Soy isoflavonesγ-H2AX by Ab assayLNCaP (human prostate cancer) cells10 μg/mLNo effect on H2AX
Curcumin25 μg/mLγ-H2AX ↑
[84]PolyphenolsComet assayLymphocytes + B(a)P5 μg/mLDNA SBs ↓
Curcumin5 and 10 μg/mLDNA SBs ↓
[85]CurcuminComet assayHCT-116 (human colon cancer) cells50 μMDNA SBs ↑
[86]CurcuminComet assayK562 (human leukaemia) cells12.5–200 μMDNA SBs ↑
Resveratrol
[87]ResveratrolChrom absHuman lymphocytes + aflatoxin10–100 μMNo effect of resveratrol alone. Dose-dependent decrease in aflatoxin-induced chrom abs
[88]ResveratrolMN; Comet assayHuman bronchial epithelial cell line HBE + Na arsenite5 μM↓ DNA SBs and MN induced by arsenite
[89]Resveratrolγ -H2AX by Ab assayHCT-116 (human colon cancer) cells25 μMγ-H2AX foci ↑: DNA damage due to toposiomerase II poisoning
[90]Resveratrolγ -H2AX by Ab assayProstate epithelial cells5 μMIonising radiation-induced damage enhanced
[91]ResveratrolComet assayRat astrocytes + ethanol1–10 μM↓ DNA SBs induced by ethanol
Lamiaceae
[39]ThymolComet assay 24 h after UVNCTC (human keratinocytes) + UV(A) or UV(B)1 μg/mLDNA SBs ↓
MNNo effect seen
γ-H2AX by Ab assayNo effect seen
Flavonoids
[92]NaringinChromosome aberrationsHuman lymphocytes treated with Cd1, 2 μg/mLCd-induced chrom abs ↓
SCENo significant effect on SCE
[93]RutinComet assayRat hepatic cell line HTC10–810 μg/mL (24 h)SBs at highest concentration
MNNo significant increase in MN—but protection against MN induced by B(a)P
[94]Quercetin; Rutinã-H2AX by Ab assayV79 lung fibroblast hamster cells100 μg/mL for 12 hMassive foci, results of lethality
[95]KaempferolComet assayHL-60 human leukemia cells75 μM, 6–48 hSBs induced
[96]QuercetinComet assayLymphocytes from healthy subjects and colon cancer patients, + food mutagens PhIP and IQ100, 250, 500 μMSBs induced by PhIP or IQ ↓
Rutin50, 250, 500 μM
[97]Fisetin, Kaempferol; Galangin; Quercetin; Luteolin; Chrysin; 7-hydroxyflavone; 7,8-dihydroxyflavone; Baicalein; RutinComet assay; MNHepG2 (human liver carcinoma) cells + B(a)P2.5–25 μMSBs induced by B(a)P ↓ (all except rutin); MN induced by B(a)P ↓ (all except rutin); Fi>Qu>Ga>Ka>Lu (more effective group); Ch, 7Fl, 7,8Fl, Ba (less effective group)
[98]FisetinComet assayHuman hepatic Huh-7 cells60 μMSBs ↑
[99]KaempferolComet assayHuman osteosarcoma cells U2-OS50, 100, 150 μMSBs ↑ (not quantitated)
[65]MyricitrinMNTK6 (human lymphoblastoid) cells20–500 μg/mL for 24 hMN ↑ (Dose-dependent)
Myricetin2.5–75 μg/mL for 24 hMN ↑ (significant?)
[100]Quercetin and rutinComet assayHuman hepatoma cell line HepG20.1, 1 and 5 μg/mL (2 h of treatment)No induction of SBs (quercetin and rutin alone)
HepG2 + Aflatoxin B, MMS, DoxPre-, co- and post-treatmentDNA damage induced by AFB1, MMS, Dox ↓ in all treatment conditions
[101]QuercetinComet assay, 8-OH–G (HPLC)Human hepatoma cell line HepG2 cells0.1, 1 and 5 μg/mL (24 h of treatment)No effect
HepG2 cells + HgCl2 and MeHgPre-, co- and post-treatmentDNA damage induced by HgCl2 and MeHg ↓ in pre- and co-treatment
[102]QuercitrinComet assayMouse epidermal cell line JB6 + UV(B)10, 20 and 80 μM, 30 minNo effect
10, 20 and 80 μM, 30 min + UV(B)UV(B)-induced SBs ↓
[51]Galangin, chrysinComet assay + FPG, EndoIIIAGS human gastric adenocarcinoma cells20 μM (1 h)Base oxidation ↑
[69]ApigeninComet assay: Chrom abs; MNHaCaT human keratinocytes + UV(B)15–25 μg/mLDNA damage ↓, Chrom abs ↓, MN ↓
PCB: polychlorinated biphenyls; chrom ab: chromosome aberration; DEN: diethylnitrosamine; Dau: Daunorubicin; TPA: tetradecanoyl phorbol acetate; ECG: epicatechin gallate; EGCG: epigallocatechin gallate; PCC: premature chromosome condensation; SCE: sister chromatid exchange; IQ: 2-amino-3-methylimidazo[4,5-f]quinolone; MMS: methylmethanesulphonate; AFB1: aflatoxin B1.
Nutrients EISSN 2072-6643 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top