Metabolism and Pharmacokinetics of Phytochemicals in the Human Body.

BACKGROUND: Phytochemicals are obtained from various plants and used for the treatment of diseases as both traditional and modern medicines. Poor bioavailability of phytochemicals is a major concern in applying phytochemicals as a therapeutic agent. It is, therefore, necessary to understand the metabolism and pharmacokinetics of phytochemicals for its implication as a therapeutic agent. METHODS: Articles on the metabolism of phytochemicals from the PubMed database. The articles were classified into the digestion, absorption, metabolism, excretion, toxicity, and bioavailability of phytochemicals and the effect of gut microbiota on the metabolism of phytochemicals. RESULTS: The metabolism of each phytochemical is largely dependent on the individual's digestive ability, membrane transporters, metabolizing enzymes and gut microbiota. Further, the form of the phytochemical and genetic make-up of the individual greatly influences the metabolism of phytochemicals. CONCLUSION: The metabolism of phytochemicals is mostly depended on the form of phytochemicals and individualspecific variations in the metabolism of phytochemicals. Understanding the metabolism and pharmacokinetics of phytochemicals might help in applying plant-based medicines for the treatment of various diseases.

Association of histone acetylation at the ACTA2 promoter region with epithelial mesenchymal transition of lens epithelial cells.

PURPOSE: Epithelial mesenchymal transition (EMT) plays a central role in the development of fibrotic complications of the lens. The current study is designed to check whether EMT of lens epithelial cells (LECs) is regulated by epigenetic modifications and to evaluate the effect of Trichostatin-A (TSA) on the transforming growth factor-ß (TGF-ß)-induced EMT. METHODS: Fetal human LECs (FHL124) were treated with TGF-ß2 in the presence or absence of TSA. Levels of mRNA, protein, as well as localization of α-smooth muscle actin (αSMA) were studied along with migration of LECs. Acetylation of histone H4 was analyzed and chromatin immunoprecipitation (ChIP) was carried out to study the level of acetylated histone H4 at the promoter of αSMA gene (ACTA2). Student's t-test was used for statistical analysis. RESULTS: TGF-ß2 treatment resulted in myofibroblast-like changes and increased migratory capacity of FHL124. Protein and mRNA expression of αSMA increased, and immunofluorescence revealed presence of extensive stress fibers. TSA treatment preserved epithelial morphology, retarded cell migration, and abrogated an increase in αSMA levels. TSA led to the accumulation of acetylated histone H4 that was reduced on TGF-ß2 treatment. However, increased level of histone H4 acetylation was found at the ACTA2 promoter region during TGF-ß treatment. CONCLUSIONS: The increased level of αSMA, a hallmark of EMT in LECs, is associated with increased level of histone H4 acetylation at its promoter region, and TSA helps in suppressing EMT by epigenetically reducing this level. TSA thus shows promising potential in management of fibrotic conditions of the lens.

Confirmation of the presence of lens epithelial cells in the anterior chamber after phacoemulsification.

AIMS: To detect the presence of lens epithelial cells in the anterior chamber of the eye at the end of phacoemulsification. METHODS: A prospective observational study was carried out on 50 patients undergoing phacoemulsification. Fluid from the anterior chamber was collected from these patients at the end of phacoemulsification. Thirty samples were processed for detection of viability using calcein AM-propidium iodide. Remaining samples were processed for immunofluorescence detection of alphaA-crystallin and vimentin. The nonparametric Mann-Whitney U test was applied. RESULTS: The presence of lens epithelial cells was confirmed in 27 of the first 30 samples. The total number of cells observed in these 27 samples were 64.70 +/- 58.49. Within these 27 samples, 35.5% were live cells and 64.5% were dead. The cells were present as single cell or in groups. Twenty three percentage samples were also positive for nucleated lens fibres. In the remaining 20 samples, 89% cells were confirmed to be lens epithelial cells. CONCLUSIONS: We show for the first time, the presence of cells in the fluid of the anterior chamber at the end of phacoemulsification. The cells were positive for alphaA-crystallin and vimentin, thereby suggesting that they were lens epithelial cells.

Rapid action of oestradiol against hydrogen peroxide-induced oxidative stress in cataractous lens epithelium: an in vitro study.

PURPOSE: To evaluate the short-term protective effects of oestradiol against damages because of oxidative stress in human lens epithelial cells (LECs). METHODS: The central zone of human lens epithelium was obtained from the cataract surgery and cultured in MEM culture medium. These cultured LECs were treated with 17beta-oestradiol for varying time intervals from 1 to 5 min followed by treatment with H(2)O(2) (5 x 10(-6) M) in the culture medium. Catalase activity was measured to access the oxidative stress levels. RESULTS: LECs exposed to H(2)O(2) (5 x 10(-6) M) showed a fourfold increase in catalase activity (407.03+/-89.11 U/microg protein) after 6 h when compared to cultured unexposed LECs (97.124+/-9.4 U/microg protein). When the cultured LECs were treated with oestradiol (5 x 10(-8) M) before H(2)O(2) treatment, the increase in catalase activity was inhibited, whereas simultaneous and post-treatments showed no effect. The catalase activity of LECs pretreated with oestradiol for 1, 2, 3, and 5 min was 259.92+/-18.37, 200.24+/-14.39, 140.50+/-19.83, and 110.01+/-14.66, respectively (P<0.0001). CONCLUSION: Antioxidative enzymes are synthesized in response to the oxidative stress signal. Upon treatment with oestrogen catalase is not synthesized. The pretreatment time of oestrogen required for its antioxidative effect can be seen within 5 min indicating non-genomic mode of action of oestrogen.

Early body weight of five strains of White Leghorn.

1. The means, standard errors and coefficients of variation for body weight at fortnightly intervals from day 1 to day 90 of five indigenous strains of White Leghorn were estimated. 2. The differences between the strain and body weight were significant at all ages while the differences between sex were significant from day 45. 3. Phenotypic correlations between body weight at day 1 with that of day 30, 60 and 90 were 0-237, -0-007 and -0.07. 4. The heritability by paternal half-sib method ranged from 0-32 to 0-54 for body weights from day 1 to day 90.