Special Issue "Catechin in Human Health and Disease"
Deadline for manuscript submissions: 30 April 2018
Catechins are natural polyphenolic compounds that are distributed in a variety of foods and herbs. Tea (Camellia sinensis) is a rich source of catechins, especially epigallocatechin-3-gallate (EGCG), which has many biological activities beneficial for human health. These include anti-cancer, anti-obesity, anti-diabetic, anti-cardiovascular, anti-infectious, hepatoprotective, and neuroprotective effects. A number of human epidemiological and clinical studies on tea have provided evidence for its health benefits and these results have been supported by cell-based and animal experiments, although studies to show conflicting results have also been reported. In addition, detailed molecular mechanisms have been proposed for the action mechanism of tea’s major catechin EGCG. One of the most attractive mechanisms is the one in which reactive oxygen species (ROS) is involved. EGCG is known to have dual actions in relation to ROS as an anti-oxidant and a pro-oxidant. Several lines of evidence have indicated that EGCG can both eliminate ROS by scavenging and enhance ROS production. However, it remains unclear what factor(s) can direct EGCG to act as an anti-oxidant or a pro-oxidant. Catechins and their oligomeric derivatives are also found in apples, persimmons, cacaos, grapes, berries, and so on. However, less information on biological activities of other catechin compounds has been available as compared with EGCG. This Special Issue is devoted to promotion of the understanding of association of catechins and human health. Research articles and reviews related to catechin compounds to reveal their health effects and their mechanistic aspects are welcomed for inclusion in this Special Issue of Molecules. Topics will include cell-based, animal studies, and human studies and special focus will be given to mechanistically-informative studies to be useful to concinnate the dual action of EGCG and other catechin compounds on ROS.
Prof. Dr. Mamoru Isemura
Manuscript Submission Information
Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.
Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Molecules is an international peer-reviewed open access monthly journal published by MDPI.
Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1800 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.
- human health
The below list represents only planned manuscripts. Some of these manuscripts have not been received by the Editorial Office yet. Papers submitted to MDPI journals are subject to peer-review.
Title: Lipid peroxidation diminishing perspective of isolated oxidized catechins (theaflavins and thearubigins) from black tea in arginine induced renal malfunctional Rats.
Author: Ali Imran
Abstract: Background: Recently oxidative stress induced maladies have amplified owing to sedentary lifestyle and monotonous diet. Introduction of plant based biomolecules may be a suitable strategy to cope with the lipid peroxidation. In this context, black tea polyphenols (theaflavin & thearubigins) are in fame among the scientific community as cost effective therapeutic agents owing to their safety, economics, structural diversity and ability to modulate various lipid peroxidation responses by halting the expression of different metabolic targets. Methods: The mandate of present investigation was to test the synergism among theaflavins & thearubigins against lipid peroxidative indicators both in vitro and in vivo. Purposely, theaflavins and thearubigins were isolated from black tea through solvent partition methods by using different solvents (Aqueous ethanol, Aqueous methanol & Water) and time intervals (30, 60 & 90 minutes) and subjected to in vitro characterization through different antioxidant indices to access the in vitro lipid peroxidation shooting effect of these bioactive moieties. Moreover, individual theaflavins contents also estimate through HPLC. For evaluation of in vivo antioxidant effect, renal malfunction was induced through arginine and forty rats were divided in four groups (10 each after power analysis) and 04 types of diets were given i.e. T0 (control diet without supplementation), T1 (Basic experimental Diet+ theaflavins supplementation @ 1g), T2 (Basic experimental Diet+ Thearubigins supplementation @ 1g) & T3 (Basic experimental Diet+ Supplementation of theaflavins+ thearubigins @ 0.5+0.5 g, respectively) for the period of 56 days. The body weight, lipid profile, glycemic responses, Renal function test, liver function test, antioxidant indices and hematological parameters were estimated at the termination of study.
Results: The results indicated that theaflavins and thearubigins isolation was significantly affected by time of extraction and solvent. In this context, aqueous ethanol at 60 minute extraction interval caused maximum extraction. Likewise, theaflavins isolate exhibited more antioxidant activity as compared to thearubigins. Moreover, the theaflavins and thearubigins based experimental diets imparted significant reduction in Lipid profile, glucose content, renal function tests and TBARS with enhancement in insulin, HDL and hematological parameters. In this context, theaflavin based diet caused maximum reduction in lipid profile and TBARS better as compared to thearubigins and theaflavins + thearubigins based. However, theaflavin+ thearubigins based diet caused highest glucose, urea & creatinine decline and maximum insulin increase & antioxidant indices as compared to other nutraceuticals.
Conclusions: it was deduced that theaflavins & thearubigins have strong antioxidative potential both in in vitro as well as in vivo to tackle the menace associated with lipid peroxidation.
Title: Probing the in vitro antioncogenic potential of isolated oxidized black tea polyphenols(theaflavins and thearubigins) against HCT-116 and HT 460 Colon and lung cancer cells"
Authors: Ali Imran1, Masood sadiq Butt2 and Hang Xiao3
Abstract: Theaflavins and thearubigins are the flavanols-3-ols found in black tea and have promising antioncogenic potential. In current research, these fractions were isolated from black tea and probe for their in vitro inhibitory effect against colon and lung cancer cell lines. Results indicated that theaflavin, thearubigins and their combination caused significant inhibition in cell viability in dose dependent manner however, theaflavin imparted maximum reduction in cell viability of HCT 116 & HT460. The flow cytometry results indicated that theaflavin, thearubigins and their combination caused substantial cell arrest at G2/M phase. The effect was more obvious in lung cancer cells (HT 460) as compared to colon cells (HCT 116). Likewise, all treatments caused apoptosis however, the combination of theaflavin and thearubigins showed highest apoptotic ability in comparison of their alone treatments. Conclusively, it was revealed that theaflavin and thearubigins showed synergistic effect and significantly inhibited the cell proliferation of HCT 116 & HT 460 in time and dose dependent manner by inducing apoptosis and cell cycle arrest however, theaflavin exhibited more pronounced effect.
Keywords: HCT 116; HT 460; Lung cancer; Theaflavins; Thearubigins; synergistic effects
Type of Article: Article
Title: Liposomal TriCurin, A Synergistic Combination of Curcumin, Epicatechin Gallate and Resveratrol, Repolarizes Tumor-Associated Microglia/Macrophages, and Eliminates Glioblastoma (GBM) and GBM Stem Cells
Abstract: We have reported earlier that a unique, synergistic molar ratio of curcumin (C), epicatechin gallate (E) and resveratrol (R), termed TriCurin, is highly potent against HPV+ tumors. We show here that a liposomal TriCurin (TrLp) triggers p53 activation and apoptosis of GL261 glioblastoma (GBM) and GBM stem cells in vitro. In GL261-implanted mouse model of GBM, TrLp causes re-polarization of M2-like GBM-associated microglia/macrophages to the tumoricidal M1 phenotype, intra-GBM recruitment of activated natural killer cells, concomitant suppression of tumor-load, and apoptosis of GBM and GBM stem cells. Thus, TrLp is a potential onco-immunotherapeutic agent against GBM tumors.