The Effects of Dietary Restriction and Aging on in Vivo and in Vitro Binding of Aflatoxin B_1 to Cellular DNA

作     者：MING W.CHOU REX A.PEGRAM PU GAO S.R.HANSARD J.G.SHADDOCK D.A.CASCIANO 

作者机构：National Center for Toxicological Research JeffersonNational Center for Toxicological Research JeffersonNational Center for Toxicological Research JeffersonNational Center for Toxicological Research JeffersonNational Center for Toxicological Research JeffersonNational Arkansas AR 72079 To whom repucsts for reprints should be addressed Arkansas AR 72079 US EPA HERL MD-74 Research Triangle Park NC 27711 Arkansas AR 72079 Arkansas AR 72079Arkansas AR 72079Center for Toxicological Research Jefferson Arkansas AR 72079 

出 版 物：《Biomedical and Environmental Sciences》 (生物医学与环境科学（英文版）)

年 卷 期：1991年第4卷第1期

页      面：134-143页

核心收录：

学科分类：100405[医学-卫生毒理学] 1004[医学-公共卫生与预防医学(可授医学、理学学位)] 1002[医学-临床医学] 100214[医学-肿瘤学] 10[医学] 

主　　题：The Effects of Dietary Restriction and Aging on in Vivo and in Vitro Binding of Aflatoxin B1 to Cellular DNA AFB 

摘      要：Laboratory animals maintained on a reduced calorie but nutritionally adequate diet have extended life spans and lowered incidences of spontaneous and chemically induced cancers compared to ad libitum- fed counterparts. Many of the effects of dietary restriction on laboratory animals have been suggested to be related to a deceleration of the aging process. The inhibition of age-related changes in xenobiotic metabolizing enzyme activities by dietary restriction has previously been reported. Alterations of these enzyme activities may cause changes in metabolic activation of carcinogens and, therefore, carcinogen-DNA binding. DNA-repair capability has also been reported to be enhanced in diet-restricted rats. Using AFB1 as a model carcinogen, we have studied in vivo and in vitro hepatic AFB1 -DNA binding, demonstrating that dietary restriction (60% of ad libitum consumption) may decrease the metabolic activation of AFB1, and subsequently reduce AFB 1-DNA binding. Our preliminary results obtained from the AFB 1-DNA binding experiments in isolated hepatocytes suggest that the observed age-dependent reduction in AFB 1-DNA binding which may be attributed to a loss of metabolic activating capability was delayed in the diet-restricted rats.