Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
Cell Biochem Funct. 2010 Jan;28(1):52-7. doi: 10.1002/cbf.1619.
Ageing is an inevitable biological process characterized by a general decline in various physiological functions. DHEA and DHEAS levels are maximal between the second and third life decades, then start to decline 2% per year, leaving a residual of 10-20% of the peak production by the eighth decade. Erythrocytes are exposed to frequent oxidative stress due to the oxygen radicals continuously generated by haemoglobin auto-oxidation. We investigated DHEA chronic (10 mg/kg, subcutaneously, for 5 weeks) effects over oxidative stress markers in erythrocytes of male Wistar rats of 3, 13 and 18 month-old. In the 13 month-old group, we found increased lipid peroxidation (LPO), superoxide dismutase (SOD), glutathione-S-transferase and catalase activities when compared to the other age groups. DHEA produced a marked increase in LPO of 13 month-old group when compared to its control. DHEA exerted this pro-oxidant effects in all ages studied, especially in age 13 month-old. It seems that at 13 month-old there would be an important depletion of some specific anti-oxidant in order to determine such susceptibility to DHEA effects. Since this approach allows a minimally invasive assessment, it would be useful as a routine method in human clinical studies investigating DHEA effects during the ageing process.
衰老是一种不可避免的生物过程，其特征是各种生理功能普遍下降。DHEA 和 DHEAS 的水平在第二和第三个生命十年之间达到最大值，然后开始每年下降 2%，到第八个十年时，剩余的产量为峰值的 10-20%。由于血红蛋白自动氧化不断产生自由基，红细胞经常受到氧化应激。我们研究了 DHEA 慢性（10mg/kg，皮下，5 周）对雄性 Wistar 大鼠红细胞氧化应激标志物的影响，这些大鼠分别为 3、13 和 18 个月大。在 13 个月大的组中，与其他年龄组相比，发现脂质过氧化（LPO）、超氧化物歧化酶（SOD）、谷胱甘肽-S-转移酶和过氧化氢酶活性增加。与对照组相比，DHEA 使 13 个月大的组的 LPO 明显增加。DHEA 在所有研究的年龄组中都产生了明显的促氧化作用，尤其是在 13 个月大的年龄组。似乎在 13 个月大时，某些特定的抗氧化剂会大量消耗，从而导致对 DHEA 作用的敏感性。由于这种方法可以进行微创评估，因此在研究衰老过程中 DHEA 作用的人类临床研究中作为常规方法可能很有用。
