Hamden Khaled, Silandre Dorothee, Delalande Christelle, Elfeki Abdelfattah, Carreau Serge
Department of Animal Ecophysiology, Faculty of Sciences, University of Sfax, PB 802, Sfax 3018, Tunisia.
Asian J Androl. 2008 Nov;10(6):837-45. doi: 10.1111/j.1745-7262.2008.00430.x.
To investigate the effects of 17beta-estradiol (E2), Peganum harmala extract (PHE) and caloric restriction (CR) on various testis parameters during aging.
Twelve month-old male rats were treated for 6 months with either E2 or PHE, or submitted to CR (40%).
Our results show that estrogens and CR are able to protect the male gonad by preventing the decrease of testosterone and E2 levels as well as the decrease of aromatase and estrogen receptor gene expressions. Indeed, E2, PHE and CR treatments induced an increase in the superoxide dismutase activities and decreased the activity of testicular enzymes: gamma-glutamyl transferase, alkaline phosphatase, lactate deshydrogenase as well as the aspartate and lactate transaminases in aged animals. In addition, the testicular catalase and gluthatione peroxidase activities were enhanced in E2, PHE and CR-treated rats compared to untreated animals at 18 months of age. Moreover, the positive effects of estradiol, PHE and CR were further supported by a lower level of lipid peroxidation. Recovery of spermatogenesis was recorded in treated rats.
Besides a low caloric diet which is beneficial for spermatogenesis, a protective antioxydant role of estrogens is suggested. Estrogens delay testicular cell damage, which leads to functional senescence and, therefore, estrogens are helpful in protecting the reproductive functions from the adverse effects exerted by reactive oxygen species (ROS) produced in large quantities in the aged testis.
研究17β-雌二醇（E2）、骆驼蓬提取物（PHE）和热量限制（CR）对衰老过程中各种睾丸参数的影响。
对12月龄雄性大鼠用E2或PHE处理6个月，或进行40%的热量限制。
我们的结果表明，雌激素和热量限制能够通过防止睾酮和E2水平的降低以及芳香化酶和雌激素受体基因表达的降低来保护雄性性腺。事实上，E2、PHE和热量限制处理可使老年动物超氧化物歧化酶活性增加，并降低睾丸酶的活性：γ-谷氨酰转移酶、碱性磷酸酶、乳酸脱氢酶以及天冬氨酸和乳酸转氨酶。此外，与18月龄未处理动物相比，E2、PHE和热量限制处理的大鼠睾丸过氧化氢酶和谷胱甘肽过氧化物酶活性增强。此外，较低的脂质过氧化水平进一步支持了雌二醇、PHE和热量限制的积极作用。在处理的大鼠中记录到精子发生的恢复。
除了低热量饮食对精子发生有益外，还提示雌激素具有抗氧化保护作用。雌激素可延缓睾丸细胞损伤，而睾丸细胞损伤会导致功能衰老，因此，雌激素有助于保护生殖功能免受衰老睾丸中大量产生的活性氧（ROS）的不利影响。
