Effect of green tea catechins on the amount of 8-hydroxydeoxyguanosine (8-OHdG) in pancreatic and hepatic DNA after a single administration of 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. Hamsters 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 injection 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 concentration of lipid peroxides (TBA values) and the amount of 8-hydroxydeoxyguanosine (8-OHdG) in nuclear DNA were measured. The concentration of lipid peroxides and the amount of 8-OHdG in the pancreas showed similar patterns of change between c- and w-ham. Soon after BOP injection, the concentration of lipid peroxides and the amount of 8-OHdG increased with a peak at 1 and 6 h, respectively. Their peak values of c-ham were significantly depressed compared with those of w-ham. Both levels returned to steady-state levels by 24 h. In the liver, the concentration 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.
Takabayashi
F
F
Hamamatsu College, University of Shizuoka, Japan.
Harada
N
N
Tahara
S
S
Kaneko
T
T
Hara
Y
Y
D000080242:8-Hydroxy-2'-Deoxyguanosine; D000818:Animals; D002392:Catechin / Q000494:pharmacology*; D002467:Cell Nucleus / Q000378:metabolism; D006224:Cricetinae; D004247:DNA / Q000187:drug effects / Q000378:metabolism*; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000378:metabolism; D005260:Female; D008054:Lipid Peroxides / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008647:Mesocricetus; D009153:Mutagens / Q000494:pharmacology; D009602:Nitrosamines / Q000494:pharmacology*; D018384:Oxidative Stress; D010179:Pancreas / Q000378:metabolism*; D013662:Tea / Q000737:chemistry
D008054:Lipid Peroxides; D009153:Mutagens; D009602:Nitrosamines; D013662:Tea; C013622:nitrosobis(2-oxopropyl)amine; D000080242:8-Hydroxy-2'-Deoxyguanosine; D002392:Catechin; D004247:DNA; D003849:Deoxyguanosine