Tea Extract Prevents Arsenic-mediated DNA Damage and Death of Murine Thymocytes in vitro

Abstract

ABSTRACT:Groundwater contamination by arsenic has created a major health hazard in Bangladesh by affecting millions of people. In this study, we report cytotoxic effects of arsenic in primary culture of murine thymocytes and the counteractive actions of tea extract to reduce this cytotoxic effects. When murine thymocytes were incubated for shorter period (1 h) with higher concentrations (50 and 100 µM) of sodium arsenite (NaAsO 2 ), cell viability was decreased to 79.06 ± 0.52% and 62.53 ± 0.23%, respectively. In case of longer incubation (16 hrs) with a wide range of NaAsO 2 concentration (1-100 µM), cell viability was reduced from 89.30 ± 0.84% to 79.0 ± 0.52% by 1 µM NaAsO 2 , and this reduction was continued with increasing concentration reaching to 29.60 ± 0.72% by 100 µM. Tea is known to possess antioxidant property and we found that this tea extract reduced NaAsO 2 -mediated death of the cells in culture. After 16 h of incubation, the chromosomal DNA of 5 µM NaAsO 2 -exposed cells was found degraded suggesting apoptotic death of the cells. Interestingly, this degradation of chromosomal DNA was blocked by tea extract. All of these results together suggest a future therapeutic application of tea extract to reduce or block arsenic toxicity.

Tea regimen, a comprehensive assessment of antioxidant and antitumor activities of tea extract produced by Tie Guanyin hybridization

“…8,[16][17][18] Numerous studies have indicated that tea catechins and polyphenols are effective oxygen scavengers of free radicals/reactive oxygen species generated due to various oxidative stress. 19,20 As the oolong tea is semi-fermented, the contents of the tea catechins and polyphenols are abundant in the extract of the tea. Hence, the STE and ATE are supposed to contain lots of tea catechins and polyphenols, as they are derived from the oolong tea.…”

Amelioration of oxidative stress-mediated cytotoxicity and genotoxicity induced by copper and flubendiamide in-vivo and in- vitro by potent antioxidants

“…Plants-based polyphenols (resveratrol, curcumin, and catechin) and α-tocopherol have been reported to possess immunomodulatory 139,140 and strong antioxidant activities 141 , promotion, progression and cellular proliferation 142,143 , and cytotoxicity induced by metals and insecticides 144,145,118,146 . Concurrent treatment with polyphenols (resveratrol, curcumin, and catechin) or α-tocopherol in present study showed decrease in TUNEL + ve cells, per cent micronuclei and comet formation in thymocytes evidently suggest the ameliorative potential against ubendiamide and copper-induced toxic effects.…”

Seasonal Variations in Antioxidant Capacities and Phenolic Contents of Tea Leaf Extracts

“…Studies reported wide health benefits of tea consumption including a reduction in cardiovascular mortality [8] and protective effect against many different types of cancer [9]. In vitro studies reported the preventive effect of tea against cellular DNA damage caused by arsenic-mediated oxidative stress [10]. These benefits of tea have been attributed mainly to its phytochemicals such as polyphenols which are important constituents of the human diet widely distributed in vegetable foods an [11].…”