Background:
Arsenic(As) in ground water has been found above the maximum permissible limit in several districts of West Bengal, India. Chronic exposure to inorganic arsenic leads to cancer as result of DNA damage. DNA damage, if not repaired culminates to initiation of carcinogenesis. This carcinogenic pathway is due to generation of reactive oxygen species (ROS) by As. Therefore, antioxidants may play a crucial role in prevention of arsenic induced carcinogenesis. Tea is a popular beverage all over the world, which is rich in antioxidants.
Aim:
The present study aimed to bio-monitor the extent of DNA damage in asymptomatic individuals who are exposed to arsenic chronically. Individuals were given tea(10 cups) a day and this intervention study was carried out to assess the protective role against arsenic induced health hazards.
Methods:
Total population was randomized into two groups, first group was given 10 cups of black tea per day, while the other group was placebo control group. ROS was measured spectrofluorimetrically, DNA damage was assessed by single cell gel electrophoresis. Antioxidant enzymes were measured following standard protocol. DNA repair enzyme status was observed by western blot analysis and by RT PCR. Expression of hypoxia inducible factor 1α(HIF1α) was determined by western blot analysis.
Results:
Black tea reduces the extent of DNA damage in individuals exposed to arsenic and that was achieved by quenching of ROS. Antioxidant enzymes have been elevated by tea. Arsenic inhibits DNA repair capacity in individuals, which was counteracted by tea. Important repair enzymes were induced. Expression of HIF1α was also decreased by tea
Conclusions:
The most popular drink, tea may act as a rescue to prevent onset of arsenic induced carcinogenesis by blocking the initiation stage in a population exposed to arsenic in West Bengal, INDIA.