Search Results (224)

Ferroptosis is a distinct form of regulated cell death driven by iron-dependent lipid peroxidation participating in various diseases. The nuclear factor erythroid 2-related factor 2 (Nrf2) is a central regulator of cellular redox homeostasis and a key determinant of ferroptosis resistance. Nrf2 activates the expression of downstream antioxidant genes to protect cells from oxidative stress and ferroptosis. Consequently, precise regulation of Nrf2 expression is crucial. Recent studies have revealed that complex epigenetic mechanisms involving DNA methylation, histone modifications, and non-coding RNA networks regulate Nrf2 expression. DNA methylation usually suppresses while histone acetylation promotes Nrf2 expression. The influences of histone methylation on NFE2L2 are site- and methylation degree-dependent. m6A modification stabilizes NFE2L2 mRNA to promote Nrf2 expression and thereby inhibit ferroptosis. This article summarizes current understanding of the epigenetic mechanisms controlling Nrf2 expression and Nrf2-mediated ferroptosis pathways and their implications in disease models. The challenges associated with the epigenetic regulation of Nrf2 and future research directions are also discussed. A comprehensive understanding of this regulatory interplay could open new avenues for intervention in ferroptosis-related diseases by fine-tuning cellular redox balance through the epigenetic modulation of Nrf2. Full article

Underutilized starch sources are gaining increasing recognition. However, the inherent functional deficiencies of native starch have limited its application in food industry. To counteract the deficiencies in its native characteristics, starch can be modified by acetylation. Two waxy starches (proso millet and amaranth) and four non-waxy starches (foxtail millet, quinoa, buckwheat, and oat) were modified by acetic anhydride and vinyl acetate, respectively. Degree of substitution of acetylated starches revealed that granule size did not significantly affect acetylation efficiency in starches from different plant origins. Acetylation increased peak and final viscosity of starches, with vinyl acetate exhibiting a more pronounced effect than acetic anhydride. Acetic anhydride decreased K and increased n values of non-waxy starches, showing reduced thickening ability. In contrast, vinyl acetate modification showed opposite trends, suggesting increased viscosity and pseudoplasticity. For non-waxy starches, G′_25°C, G′_0.1Hz, G′_20Hz and gel hardness decreased after acetylation, indicating that acetylation contributed to a less solid and less elastic gel network. The extent of change in vinyl acetate modification was more pronounced than that of acetic anhydride. For waxy starch, vinyl acetate modification decreased tan δ_25°C and increased gel hardness. In summary, acetylation reagent type was the major factor determining the pasting properties of acetylated starch, but the presence or absence of amylose would influence the rheological and gel properties of acetic anhydride and vinyl acetate modified starches. These findings could help unlock the potential applications of acetylated underutilized starches in the food industry. Full article

Background/Objectives. Diabetic peripheral neuropathy is a debilitating disease-related complication with a significant impact on quality of life. Its management represents a therapeutic challenge. Antioxidant agents such as α-lipoic acid, N-acetyl cysteine, and glutatione may be useful treatment strategies. Methods. A real-world, observational, retrospective, case–control study involving consecutive subjects with type 2 diabetes with diabetic peripheral neuropathy was performed. Participants who were supplemented with three different formulations for 12 weeks (high-dose α-lipoic acid (800 mg); low-dose α-lipoic acid (100 mg) plus glutathione (200 mg) plus Vitamin D (800 IU); N-acetyl cysteine (600 mg) plus glutathione (200 mg) plus Vitamin D (800 IU)) were compared with a non-treated control group. Questionnaires aimed at investigating the degree of disability and quality of life were administered. The primary endpoint was the change in neuropathic pain intensity measured by the Numerical Rating Scale (NRS). Results. Among 750 consecutive screened subjects with type 2 diabetes, 98 (13%) had diabetic neuropathy (mean age 66.7 ± 7.6 years, diabetes duration 11.3 ± 6.7 years, HbA1c 8.1 ± 1.5%, 43.8% insulin-treated). When comparing the differences between treatment groups in the changes in individual questionnaire scores between baseline and follow-up, all three supplements showed significant reductions compared to the control group in the NRS scale scores. No side effects have been reported during the study. Conclusions. As well as lipoic acid, other substances with specific activity on the genesis of neuropathic pain, such as N-acetyl cysteine and glutathione, have proved effective in reducing the intensity of pain. Full article

Stem cells, both normal somatic (SSC) and cancer stem cells (CSC) exist in minimally two states, i.e., quiescent and activated. Regulation of these two states, including their reliance on different metabolic processes, i.e., FAO and glycolysis in quiescent versus activated stem cells respectively, involves the analysis of a complex array of factors (nutrient and oxygen levels, adhesion molecules, cytokines, etc.) to initiate the epigenetic changes to either depart or enter quiescence. Quiescence is a critical feature of SSC that is required to maintain the genomic integrity of the stem cell pool, particularly in long lived complex organisms. Quiescence in CSC, whether they are derived from mutations arising in SSC, aberrant microenvironmental regulation, or via dedifferentiation of more committed progenitors, is a critical component of therapy resistance and disease latency and relapse. At the beginning of vertebrate evolution, approximately 450 million years ago, a gene duplication generated the two members of the Kat3 family, CREBBP (CBP) and EP300 (p300). Despite their very high degree of homology, these two Kat3 coactivators play critical and non-redundant roles at enhancers and super-enhancers via acetylation of H3K27, thereby controlling stem cell quiescence versus activation and the cells metabolic requirements. In this review/perspective, we discuss the unique regulatory roles of CBP and p300 and how specifically targeting the CBP/β-catenin interaction utilizing small molecule antagonists, can correct lineage infidelity and safely eliminate quiescent CSC. Full article

Apple pomace pectins, extracted using various methods (water, cellulase, arabinase, and arabinase with mannanase), and commercial apple pectin were studied, analyzing their morphology and chemical structure. The microscopic analysis revealed morphological differences, with a log-normal particle size distribution observed in most samples, except for those extracted with water. Cellulase-extracted pectin exhibited the most spherical morphology, while enzymatically extracted pectins displayed uneven surfaces. The FT-IR analysis indicated structural changes, shifts in O-H bands, and the degree of methoxylation (DM) ranged from 30.25% to 58%, with all the pectins classified as high-methoxy pectins. The NMR (¹H and ¹³C) analysis confirmed the presence of arabinans, galactans, galacturonans, and rhamnose, and the calculated DM and acetylation (DAc) values were consistent with the results obtained using conventional methods. These results provide insight into the influence of extraction methods on pectin properties, which is relevant to the pharmaceutical and food industries, and confirm the structural similarity between enzymatically extracted pectins and commercial pectin. Full article

Wood flour (WF)-reinforced poly (butylene adipate-co-terephthalate) (PBAT) composites were successfully fabricated by injection-molding process after being mixed using an extruder. The effects of fiber modifications, including mercerization, acetylation, as well as coupling agent treatment on the properties of WF/PBAT composites, were studied. The results indicated that all the modifications increased the mechanical properties (e.g., tensile strength, tensile modulus, flexural strength, flexural modulus, elongation at break, and Charpy impact strength) of the composites. After modification, all the composites showed better interfacial bonding, hydrophobicity, and thermal properties compared to the untreated fiber composites; meanwhile, the moisture absorption test showed that all the modified fiber composites exhibited a much lower saturated water absorption rate than untreated ones. WF modification by addition of a coupling agent could improve the properties most obviously, except for the tensile strength, elongation at break, and saturated water absorption rate. By this modification, the tensile modulus, flexural strength, flexural modulus, impact strength, onset temperature during thermal degradation, degree of crystallinity, and water contact angle of the composite were 313.47 MPa, 20.55 MPa, 830.79 MPa, 16.01 kJ/cm², 367.71 °C, 17.10%, and 101.8°, all increased from those of untreated composites by 17.95%, 30.73%, 87.52%, 35.79%, 61.49%, 25.67 °C, 89.16%, and 6.6°, respectively. Full article

Pico Island is one of the islands of the Azores archipelago located in the North Atlantic Ocean, where there are very specific conditions for vine cultivation. In this context, there is scarce knowledge related to grape ripening under these conditions. Thus, the aim of this study was to evaluate several physicochemical parameters, the phenolic composition, antioxidant capacity, and varietal aromatic potential, of the “Merlot”, Syrah”, and “Saborinho” grape varieties cultivated on Pico Island over three vintages. The outcomes obtained demonstrated that “Merlot” grapes showed a tendency for significantly higher values of estimated alcohol degree, total phenols, flavonoid and non-flavonoid phenols, total anthocyanins, color intensity, and antioxidant capacity over the three vintages. In addition, for individual anthocyanins, “Merlot” and “Syrah” grapes showed a predominance of acetyl-anthocyanins in relation to p-coumaroylated forms, while for “Saborinho” grapes, an oppositive tendency was observed. For varietal aromatic potential, only in the 2021 vintage was it possible to detect significantly different values between the three grape varieties studied. In this case, “Merlot” and “Syrah” grapes showed the significantly highest values. Considering all parameters analyzed, the results obtained for the “Merlot” grape variety seem to show a better adaptation of this variety to the conditions of Pico Island than the remaining two varieties studied. Full article

Alpinia oxyphylla Miq. is an important undergrowth species in southern China. The fruits of A. oxyphylla are recognized as one of “the four famous south medicines” and are also used in the production of preserved fruit. However, as non-medicinal parts, their stems and leaves are unutilized. In order to promote resource recycling, the chemical components of such stems and leaves were investigated, and we evaluated their melanin inhibitory potential through DPPH and ABTS radical scavenging, tyrosinase inhibition, and melanin production inhibition in B16 cells. Five new compounds, aloxy A (1), kaempferol 3-O-α-L-rhamnosyl-(1 → 2)-(3″,4″-diacetyl-β-D-glucuronate methyl ester) (2), quercetin 3-O-α-L-rhamnosyl-(1 → 2)-(3″,4″-diacetyl-β-D-glucuronate methyl ester) (3), kaempferol 3-O-α-L-rhamnosyl-(1 → 3)-(4″-acetyl-β-D-glucuronate methyl ester) (4), and kaempferol 3-O-α-L-rhamnosyl-(1 → 2)-(3″-acetyl-β-D-glucuronate methyl ester) (5), and seventeen known ones (6–22) were isolated and identified from the stems and leaves of A. oxyphylla. Among these compounds, 19 compounds presented tyrosinase inhibitory activities, among which aloxy A (1), hexahydrocurcumin (7), gingerenone A (8) and 4,4′-dimethoxy-3′-hydroxy-7,9′:7′,9-diepoxylignan-3-O-β-D-glucopyranoside (22) showed strong inhibitory activity, with IC₅₀ values between 6.26 ± 0.42 and 22.04 ± 1.09 μM, lower than the positive control (Kojic acid, IC₅₀ = 37.22 ± 1.64 μM). A total of 15 compounds exhibited varying degrees of DPPH and ABTS radical scavenging activities. In addition, 1, 2, and 7 showed melanin production inhibition activity in B16 cells, and the effects presented as concentration-dependent. The above results indicate that the stems and leaves of A. oxyphylla are rich with phenolic compounds, and display tyrosinase inhibition and antioxidant activities, which could lead to potential applications related to melanin production inhibition such as in the development of cosmetics. Full article

The interactions and structural organization of water molecules play a crucial role in a wide range of physical, chemical, and biological processes. The ability of water to form hydrogen bonds (H-bonds) underpins its unique properties and enables it to respond dynamically to various environmental factors. These interactions at the molecular level may affect vital processes like protein folding, enzyme activity, and cellular organization. The presence of solutes and spatial constraints can alter the H-bonding network of water, and these effects are ubiquitous in the biological environment. In this study, we analyzed the fluorescence of 2-acetyl-6-(dimethylamino)naphthalene (ACDAN) fluorescence emission in water solutions containing kosmotropic and chaotropic salts and in agar hydrogels. Recently, this dye has proven invaluable in studying water network structure and dynamics, as its fluorescence signal changes based on the local dielectric environment, revealing variations in the dipolar relaxation of water. Our results show that ACDAN spectral response correlates with the degree of water ordering, providing important insights into solute–water interactions and water dynamics in free and confined environments. Full article

Isocitrate dehydrogenase (IDH) and O⁶-methylguanine-DNA methyltransferase (MGMT) genes are critical molecular markers in determining treatment options and predicting the prognosis of adult-type diffuse gliomas. Objectives: this study aimed to investigate whether multimodal MRI enables the differentiation of genotypes in adult-type diffuse gliomas. Methods: a total of 116 adult-type diffuse glioma patients (61 males, 51.5 (37, 62) years old) who underwent multimodal MRI before surgery were retrospectively analysed. Multimodal MRI included conventional MRI, proton magnetic resonance spectroscopy (¹H-MRS), and diffusion tensor imaging (DTI). Conventional visual features, N-acetyl-aspartate (NAA)/Creatine (Cr), Choline (Cho)/Cr, Cho/NAA, fractional anisotropy (FA), mean diffusivity (MD), and diffusion histogram parameters were extracted on the whole tumour. Multimodal MRI parameters of IDH-mutant and IDH-wildtype gliomas were compared using the Mann–Whitney U test, Student’s t-test, or Pearson chi-square tests. Logistic regression was used to select the MRI parameters to predict IDH-mutant gliomas. Furthermore, multimodal MRI parameters were selected to establish models for predicting MGMT methylation in the IDH-wildtype gliomas. The performance of models was evaluated by the receiver operating characteristics curve. Results: a total of 56 patients with IDH-mutant gliomas and 60 patients with IDH-wildtype glioblastomas (GBM) (37 with methylated MGMT and 17 with unmethylated MGMT) were diagnosed by 2021 WHO classification criteria. The enhancement degree (OR = 4.298, p < 0.001), necrosis/cyst (OR = 5.381, p = 0.011), NAA/Cr (OR = 0.497, p = 0.037), FA-Skewness (OR = 0.497, p = 0.033), MD-Skewness (OR = 1.849, p = 0.035), FA_mean (OR = 1.924, p = 0.049) were independent factors for the multimodal combined prediction model in predicting IDH-mutant gliomas. The combined modal based on conventional MRI, ¹H-MRS, DTI parameters, and histogram performed best in predicting IDH-wildtype status (AUC = 0.890). However, only NAA/Cr (OR = 0.17, p = 0.043) and FA (OR = 0.38, p = 0.015) were associated with MGMT methylated in IDH-wildtype GBM. The combination of NAA/Cr and FA-Median is more accurate for predicting MGMT methylation levels than using these elements alone (AUC, 0.847 vs. 0.695/0.684). Conclusions: multimodal MRI based on conventional MRI, ¹H-MRS, and DTI can provide compound imaging markers for stratified individual diagnosis of IDH mutant and MGMT promoter methylation in adult-type diffuse gliomas. Full article

The manuscript presents research focusing on the adsorption and emulsion properties of starch hydrolysates modified through acetylation, oxidation, and cross-linking. The techniques used in this study included measurements of equilibrium surface tension (du Noüy ring) dynamic surface tension (drop shape analysis), and the preparation and evaluation of emulsion stability (TURBISCAN). The surface activity of the acetylated starch hydrolysates is affected by the degree of acetylation. The acetylated starch 0.02Ac-H exhibited higher surface activity than the more highly substituted derivative 0.1Ac-H. Furthermore, it was shown that the surface activity of the components increased as the acetylated oxidized starch underwent hydrolysis. The fractions collected after 180 min using a membrane with a low separation capability (8 kDa) revealed the highest capacity for reducing surface tension. In binary systems consisting of starch derivatives and surfactants, synergistic effects in reducing surface tension were particularly noticeable in systems containing ionic surfactants. The addition of a cationic surfactant to the modified starch hydrolysate solution (1:6 mol/mol) resulted in a significantly more efficient saturation of the air/water interface. This study demonstrated that emulsions stabilized with modified starch hydrolysates remained stable over time, even when these hydrolysates constituted up to 60% of the emulsifier mixture. Full article

The black soldier fly (BSF) Hermetia Illucens can grow rapidly and on a wide variety of organic materials, and it is extensively used as a means of disposing of household organic waste. Different phases of the life cycle of BSF larvae (BSFL) are used in this work to extract chitin after the removal of lipids, mineral salts, and proteins. Multiple techniques, such as X-ray diffractometry, infrared spectroscopy, solid-state Nuclear Magnetic Resonance (¹³C ss-NMR) and thermogravimetric analysis, are used to investigate the chemical and physical characteristics of the extracted samples of chitin, which shows a high degree of acetylation (from 78% to 94%). The extracted chitin shows an increase of the thermal stability of 20 °C in the initial stage of life and 35 °C at the end of the life cycle if compared with a commercial standard. Moreover, the extracted chitin shows an increase in the crystallinity degree during the BSFL growth time (from 72% to 78%). Full article

Several chemical analytical methods were applied to characterize the chemical structure of polysaccharides extracted from discarded apples and pomegranate peels using hydrodynamic cavitation methods in a circular economy perspective. In particular, the purity of the polysaccharides and the degrees of acetylation and methylation were evaluated by proton Nuclear Magnetic Resonance (¹H-NMR) analysis; simple sugars and galacturonic acid were analyzed simultaneously by High-Performance Anion Exchange Chromatography—Pulsed Amperometric Detector (HPAEC-PAD); the molecular weight of the extracted polysaccharides was determined by High-Performance Size Exclusion Chromatography-Refractive Index Detector (HPSEC-RID). The results showed a negligible presence of co-precipitated proteins/tannins, easily removed by dialysis, as well as other co-precipitated molecules such as monosaccharides and organic acids. Polysaccharides from apples consisted mainly of pectic material with a prevalence of homogalacturonans. Polysaccharides from pomegranate peels showed greater compositional variability with significant amounts of arabinose and galactose, a lower content of pectin, and the presence of rhamnogalacturonans I. Both polysaccharides were highly methylated and differed in the degree of acetylation, which could lead to different properties. Polysaccharides from apples presented two main molecular weights (>805 kDa and 348–805 kDa, respectively), while those from pomegranate peel showed a major fraction at 348 kDa and minor fractions < 23 kDa. In conclusion, the research tools proposed by this study have allowed defining the macrostructure of polysaccharides in a quick and efficient way to valorize these food by-products. Full article

This study aimed to analyze the structure of polysaccharides from eight different Dendrobium species and their protective effects on gastric mucosa. Ultraviolet (UV) analysis showed that the contents of eight polysaccharides ranged from 51.89 ± 6.91% to 80.57 ± 11.63%; the degree of acetylation ranged from 0.17 ± 0.03 to 0.48 ± 0.03. High-performance liquid chromatography (HPLC) results showed that these polysaccharides were mainly composed of mannose (Man) and glucose (Glc) with a small amount of galactose (Gal) and arabinose (Ara), and the monosaccharide ratios of different Dendrobium species were different. High-performance size exclusion chromatography—multi angle light scattering—refractive index detector (HPSEC-MALS-RID) showed that the molecular weight (Mw) of all Dendrobium polysaccharides was >1 × 10⁵ Da; D. huoshanense had the lowest molecular weight. Subsequently, an ethanol injured GES-1 cell model was constructed to evaluate the gastric mucosal protective potential of polysaccharides from eight different Dendrobium species. The results showed that the protective effect of the low concentration 50 μg/mL DHP treatment group was similar to that of the control group (p > 0.05), and the cell viability could reach 97.32% of that of the control group. Based on the polysaccharide composition, different kinds of Dendrobium have different degrees of migration and repair effects on GES-1 damaged cells, and the effect of DHP is slightly better than that of other varieties (83.13 ± 1.05%). Additionally, Dendrobium polysaccharides alleviated ethanol-induced oxidative stress and inflammatory response in gastric mucosal cells by enhancing the activity of antioxidant enzymes (superoxide dismutase, glutathione peroxidase, catalase) and reducing the levels of malondialdehyde and reactive oxygen species. Overall, DHP can most effectively protect gastric mucosa. These findings enhance our understanding of the relationship between the structure and biological activity of Dendrobium polysaccharides, providing a foundation for the quality control of Dendrobium. Furthermore, these findings offer theoretical support for the development of Dendrobium polysaccharides as nutraceuticals to treat digestive system diseases. Full article

Heat stress severely affects the yield and quality of maize. Melatonin (N-acetyl-5-methoxy-tryptamin, MT) plays an important role in various types of stress resistance in plants, including heat tolerance. Enolase (ENO, 2-phospho-D-glycerate hydrolyase) contributes to plant growth, development, and stress response. As of now, the molecular mechanisms by which MT and ENO1 affect heat tolerance are unknown. In our research, we have revealed that heat stress (H) and heat stress + MT (MH) treatment upregulate ZmENO1 expression levels by 15 and 20 times, respectively. ZmENO1 overexpression and mutant maize lines were created by transgenic and genome editing. These results illustrate that heat stress has a significant impact on the growth of maize at the seedling stage. However, ZmENO1-OE lines showed a lower degree of susceptibility to heat stress, whereas the mutant exhibited the most severe effects. Under heat stress, exogenous application of MT improves heat resistance in maize. The ZmENO1-OE lines exhibited the best growth and highest survival rate, while the zmeno1 mutants showed the least desirable results. Following treatment with H and MH, the level of MT in ZmENO1-OE lines exhibited the greatest increase and reached the maximum value, whereas the level of MT in the zmeno1 mutant was the lowest. Heat stress decreased the maize’s relative water content and fresh weight, although ZmENO1-OE lines had the highest and zmeno1 mutants had the lowest. Heat stress led to an increase in the levels of MDA, hydrogen peroxide, and superoxide in all plants. Additionally, the ionic permeability and osmotic potential of the plants were significantly increased. However, the levels of MT were decreased in all plants, with the greatest decrease observed in the ZmENO1-OE lines. Interestingly, the zmeno1 mutant plants had the highest expression levels of MT. Heat stress-induced upregulation of ZmSOD, ZmPOD, ZmAPX, ZmCAT, ZmP5CS, and ZmProDH in all plants. However, the ZmENO1-OE lines exhibited the greatest increase in expression levels, while the zmeno1 mutants showed the lowest increase following MT spraying. The patterns of SOD, POD, APX, and CAT enzyme activity, as well as proline and soluble protein content, aligned with the variations in the expression levels of these genes. Our findings indicate that MT can upregulate the expression of the ZmENO1 gene. Upregulating the ZmENO1 gene resulted in elevated expression levels of ZmSOD, ZmPOD, ZmAPX, ZmCAT, ZmP5CS, and ZmProDH. This led to increased activity of antioxidant enzymes and higher levels of osmoregulatory substances. Consequently, it mitigated the cell membrane damage caused by heat stress and ultimately improved the heat resistance of maize. The results of this study provide genetic resources for molecular design breeding and lay a solid foundation for further exploring the molecular mechanism of MT regulation of heat stress tolerance in maize. Full article