补肾中药对老年大鼠肝细胞核内活性基因的影响

Effect of Chinese Herbal Medicine for Tonifying Kidney on Active Gene of Liver Cell Nuclei in Old Rat

目的:观察老年、老年加补肾中药及青年组大鼠细胞核内活性基因的变化,探求补肾中药延缓衰老的分子生物学机理。方法:以脱氧核糖核酶Ⅰ(DNabe Ⅰ)为探针,脱氧核糖核酸Ⅱ(DNaseⅡ)为参照,分别切割老年、青年、老年加补肾药大剂量组、老年加补肾药小剂量组大鼠肝细胞核内染色质,研究4组大鼠肝细胞核活性基因的变化。酶切后进行琼脂糖电泳,并将胶板置于紫外灯下观察、摄影。结果:观察到在不同的时间内,对 DNaseⅠ的消化敏感性依次为青年组大于补肾组(大剂量组与小剂量组无显著差异),补肾组大于老年组,而4组对 DNaseⅡ敏感性无差异。结论:老年大鼠肝细胞核内染色质对 DNaseⅠ的敏感性下降。补肾中药延缓衰老的分子生物学基础可能与减缓细胞核内活性基因丢失有关。

Objective:To explore the molecular mechanism of Chinese herbal medicine for tonifying Kidney(CHM-TK)in delaying senility.Methods:Rats were divided into 4 groups,Group A:old rats group;Group B:old rats fed with high dose CHM- TK;Group C:old rats fed with low dose CHM-TK and Group D:young rats group.The changes of active genes in liver cell nuclei of experimental animals were observed by using DNase Ⅰ as active gene probe and DNase Ⅱ as control.Liver cell nuclei were digested with DNase Ⅰ and DNase Ⅱ and the fragments were observed by gel electrophoresis and photog- raphy.Results:The digestive sensitivity to DNase Ⅰ of different groups was different,i.e.Group D>Group B and Group C>Group A.While the sensitivity to DNase Ⅱ of the 4 groups was similar to each other.Conclusion:The sensi- tivity of chromatin in liver cell nuclei to DNase Ⅰ reduces in old rats.The molecular mechanism of CHM-TK in delaying senility may be related to its effect in slowing the losing velocity of active gene in cell nuclei.