8-oxo-G在快速老化小鼠SAMP8海马中表达的增龄性变化研究

目的观察8-氧鸟嘌呤核苷(8-oxo-G)在SAMP8品系快速老化小鼠海马不同区域的表达,以探讨其与SAMP8小鼠增龄性变化的关系。方法选用1、4、8、12月龄的快速老化小鼠SAMP8以及同龄抗快速老化小鼠SAMR1(对照组),每组各6只,采用免疫组化方法检测小鼠海马不同区域8-oxo-G的表达。结果8-oxo-G主要在SAM小鼠海马神经元胞浆内表达。对照组SAMR1 1月龄小鼠海马CA1和CA3区8-oxo-G表达显著高于其他月龄组(P<0.05),4、8、12月龄小鼠间其表达差异无统计学意义(P>0.05);SAMP8 12月龄小鼠海马8-oxo-G的表达显著高于1、4、8月龄组(P<0.05);SAMP8和SAMR1小鼠之间比较,1、4月龄间差异无统计学意义(P>0.05),8、12月龄间差异有统计学意义(P<0.05)。结论SAMP8小鼠海马8-oxo-G的表达除1月龄外随月龄增加而增加,提示8-oxo-G的表达增加与SAMP8小鼠的快速老化相关,有可能为增龄,甚至AD的生物学标志。

The Age-related Increase of 8-oxo-G in the Hippocampi of SAMP8

Objective To observe the amount of 8-oxo-G in the hippocampi of Senescence-accelerated mouse P8(SAMP8),and to discuss its relation with the aging change of SAMP8.Methods Random sampling was adopted to select 1-,4-,8-and 12-month old SAMP8 and its control strain antisenescence-accelerated mouse(SAMR1,6 mice each group),using immunohistochemisry analysis to explore the change of 8-oxo-G in the hippocampis of two strains of mice.Results 8-oxo-G could be detected almost exclusively in cytoplasm of neurons throughout the whole hippocampi of both strains at all ages tested.There was no significant difference in both CA1 and CA3 subregion of SAMR1 between the 4-,8-and 12-month old mice(P>0.05).And the differences between the two strains of 1-and 4-month-old mice were not significant.But there was a significant increase in 8-and 12-month-old animals compared with the 4-month-old mice(P<0.05) and the age-matched SAMR1(P<0.05).In all two substrains,there was a significant increase in 1-month-old animals compared with the 4-month-old mice(P<0.05).Conclusions Except for 1-month old mice,8-oxo-G in RNA increased markedly from as early as 8-month-old for SAMP8,and might be a biological marker of aging even of AD.