Yang Jiancheng, Zong Xiaomeng, Wu Gaofeng, Lin Shumei, Feng Ying, Hu Jianmin
College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, 110866, People's Republic of China.
Amino Acids. 2015 Aug;47(8):1549-58. doi: 10.1007/s00726-015-1995-0. Epub 2015 May 10.
In males, the decline of androgen synthesis, spermatogenesis and sexual function are the main phenotypes of aging, which may be attributed to testicular dysfunction. Taurine can act as an antioxidant, a testosterone secretion stimulator, a sperm membrane stabilizer and motility factor, and an anti-apoptotic agent. Recent observational studies suggested that taurine may play an important role in spermatogenesis, but to date whether taurine has anti-aging effects on testes remains unknown. We found that in aged rats testicular SDH and G6PDH activities, marker enzymes of testes, serum testosterone, testicular 3β-HSD and 17β-HSD mRNA expression levels were significantly increased by taurine treatment. Taurine administration also markedly raised the sperm count, viability and motility, decreased the sperm abnormality. Our data suggested that taurine can postpone testicular function deterioration in aged rats. Importantly, we observed obvious elevation of testicular antioxidant enzymes (SOD, GSH, GSH-Px) activities, and remarkable reduction of ROS and MDA by taurine administration, indicating taurine can decrease testicular oxidative stress and lipid peroxidation in aged rats. Finally, we found taurine effectively reduced testicular DNA fragmentation, increased testicular Bcl-2 protein expression, and decreased cytochrome c, Bax, Fas, FasL and caspase-3 expression, suggesting taurine can prohibit aged testicular apoptosis by mitochondrial dependent and independent signal pathway. In summary, our results indicated that taurine can suppress testicular function deterioration by increasing antioxidant ability and inhibiting apoptosis.
在男性中，雄激素合成、精子发生和性功能的衰退是衰老的主要表型，这可能归因于睾丸功能障碍。牛磺酸可作为抗氧化剂、睾酮分泌刺激剂、精子膜稳定剂和运动因子以及抗凋亡剂。最近的观察性研究表明，牛磺酸可能在精子发生中起重要作用，但迄今为止，牛磺酸是否对睾丸具有抗衰老作用仍不清楚。我们发现，在老年大鼠中，通过牛磺酸处理，睾丸标志酶SDH和G6PDH的活性、血清睾酮、睾丸3β-HSD和17β-HSD mRNA表达水平显著增加。给予牛磺酸还显著提高了精子数量、活力和运动能力，降低了精子异常率。我们的数据表明，牛磺酸可以延缓老年大鼠睾丸功能的衰退。重要的是，我们观察到给予牛磺酸后睾丸抗氧化酶（SOD、GSH、GSH-Px）的活性明显升高，ROS和MDA显著降低，表明牛磺酸可以降低老年大鼠睾丸的氧化应激和脂质过氧化。最后，我们发现牛磺酸有效减少了睾丸DNA片段化，增加了睾丸Bcl-2蛋白表达，并降低了细胞色素c、Bax、Fas、FasL和caspase-3的表达，表明牛磺酸可以通过线粒体依赖和非依赖信号通路抑制老年睾丸细胞凋亡。总之，我们的结果表明，牛磺酸可以通过提高抗氧化能力和抑制细胞凋亡来抑制睾丸功能的衰退。
