患糖尿病12周大鼠睾丸生精细胞周期及其凋亡与抗氧化水平的变化

Changes of Cycle and Apoptosis of Spermatogenic Cells and Antioxidant Capacity in Male Rats with Diabetes Mellitus

目的:探讨患糖尿病12周大鼠睾丸生精细胞周期及其凋亡和血清与睾丸抗氧化水平的变化。方法:W istar大鼠随机分为正常对照组10只,糖尿病组20只。腹腔注射链佐脲菌素(STZ)建立糖尿病大鼠模型,12周末记录其存活率、体重和睾丸重量;采用流式细胞术检测生精细胞周期各时相细胞百分率和细胞凋亡率,应用硫代巴比妥酸法(TBAR s)、硝酸还原酶法、黄嘌呤氧化酶法、二硫代二硝基苯甲酸法(DTNB)和分光光度法分别检测血清及睾丸丙二醛(MDA)和一氧化氮(NO)含量,超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)和NO合酶(NOS)活性。结果:大鼠患糖尿病12周后,其存活率、体重和睾丸重量显著低于正常对照组(P<0.05);G0/G1期生精细胞显著增加(P<0.05),S期和G2/M期细胞减少,即发生了G0/G1期细胞阻滞;生精细胞凋亡率明显增加(P<0.05)。与正常对照组相比,糖尿病大鼠血清和睾丸MDA含量增加,其中后者增加明显(P<0.01);血清及睾丸SOD活性降低;血清GSH-Px活性显著低于对照组(P<0.05),而睾丸GSH-Px活性显著增高(P<0.01);血清和睾丸NO含量增高,尤其前者显著升高(P<0.01);血清NOS活性显著降低(P<0.05)。结论:睾丸组织及血清MDA和NO含量增加,以及抗氧化酶活性降低,可能与糖尿病大鼠生精细胞G0/G1期阻滞和凋亡增多所致生精障碍有关。

Objective： To explore the changes of cycle and apoptosis of spermatogenic cells and antioxidant capacity of the serum and testis in male rats with diabetes mellitus. Methods： Thirty male rats were divided into two groups, 10 for normal control and 20 for the diabetes group. The rats were injected intraperitoneally with streptozocin（STZ） to develop diabetes, and 12 weeks later, their survival rate and testis weight were recorded. The percentage of G0/G1, S and G2/M phases and apoptosis in spermatogenic cells were measured with flow cytometry （FCM）. Malondialdehyde （MDA） and nitric oxide （NO） levels, superoxide dismutase （SOD）, glutathione peroxidase （GSH-Px） and NO synthase （NOS） activities in the serum and testis were measured with thiobarbituric acid reactive substances （ TBARs）, nitric acid deoxidized enzyme, xanthine oxidative enzyme, 5,5＇-Dithiobis （2,2＇-nitrobenzoate） （ DTNB ） and visible light photometer methods, respectively. Results： Twelve weeks after the male rats got diabetes, their survival rate, body weight and testis weight were significantly lower （P〈0.05）, and the percentages of G0/G1 phases and apoptotic spermatogenic cells were obviously higher （P 〈 0.05 ） than the normal control. At the same time, the percentage of S and G2/M phases spermatogenic cells decreased. So the spermatogenic cells were arrested in G0/G1 phase. In the diabetic rat serum and testis, especially in the testis, MDA levels were distinctly higher and SOD activities were significantly lower than those in the control. Serum GSH-Px activities of the diabetic rats were significantly lower（ P 〈 0.05 ）, while testis GSH-Px activities were significantly higher than those in control group（ P 〈0.01 ）. NO contents in the serum and testis of the diabetic rats （P 〈 0.01 ） increased significantly, particularly the former, while NOS activities in the serum decreased significantly as compared with the control （ P 〈 0.05 ）. Conclusion ： The increase in testis and serum MDA levels and NO contents and the decrease in the antioxidant enzyme activity of the diabetic rats may be relevant to spermatogenic disorder caused by the increase of G0/G1 phases arrest and spermatogenic cells apoptosis.