EFFECT OF GREEN TEA CATECHINS ON THE AMOUNT OF 8-HYDROXYDEOXYGUANOSINE (8-OHDG) IN PANCREATIC AND HEPATIC DNA AFTER A SINGLE ADMINISTRATIONOF N-NITROSOBIS(2-OXOPROPYL)AMINE (BOP)

Effects of green tea catechins on N-nitrosobis(2-oxopropyl)amine (BOP) -induced oxidative stress in pancreas and liver were examined. Hamster s were divided into two groups: one group was given free access to a 0 .1% solution of green tea catechins as drinking water (c-ham) and the other to plain tap water (w-ham) for 1 week before subcutaneous inject ion of BOP 20 mg/kg body weight. Zero, 1, 2, 6, 12, 24, and 48 h after BOP injection, the pancreas and liver were excised and the tissue con centration of lipid peroxides (TEA values) and the amount of 8-hydroxy deoxyguanosine (8-OHdG) in nuclear DNA were measured. The concentratio n of lipid peroxides and the amount of 8-OHdG in the pancreas showed s imilar patterns of change between c-and w-ham. Soon after BOP injectio n, the concentration of Lipid peroxides and the amount of 8-OHdG incre ased with a peak at 1 and 6 h, respectively. Their peak values of c-ha m were significantly depressed compared with those of w-ham. Both leve ls returned to steady-state levels by 24 h. In the liver, the concentr ation of lipid peroxides and the amount of 8-OHdG were not affected by BOP administration. These results suggest that BOP induces oxidative damages in the target organ and oral intake of green tea catechins has a protective effect on the oxidative stress.