大肠埃希菌感染诱导小鼠生精细胞凋亡的研究  

Study on apoptosis of spermatogenic cell induced by Escherichia coli infection in mice

作　　者：于爱莲[1] 李忠培[2] 邓文[1] 申姜赢[1] 朱小明[1] 刘莉[1] 庄东明[1] 

机构地区：[1]泰山医学院,山东泰安271000 [2]泰安市中心医院,山东泰安271000

出　　处：《中国病原生物学杂志》2008年第12期886-889,902,F0003,共6页Journal of Pathogen Biology

基　　金：山东省计生委资助课题(No.2005-13)

摘　　要：目的探讨大肠埃希菌感染对雄性小鼠生精细胞凋亡以及对凋亡调控基因Fas/FasL的影响,进一步阐明大肠埃希菌感染致男性不育的分子机理。方法用大肠埃希菌直接注入成年雄性小鼠膀胱内模拟逆行感染的途径,感染后第7d处死小鼠,取睾丸组织分别作HE染色和用TUNEL法观察生精细胞凋亡及睾丸的病理变化;免疫组化法检测Fas/FasL在睾丸组织中的表达,同时检测精子数量、精子活动率和精子畸形率。结果大肠埃希菌感染小鼠后生精细胞的凋亡指数及Fas和FasL表达水平分别为(18.50±1.50)%、(48.10±4.19)%和(34.60±4.18)%,对照组分别为(7.40±1.69)%、(23.50±2.66)%和(19.10±4.30)%,差异均有统计学意义(P均<0.05)。感染组精子数量、精子活动率和精子畸形率分别为(6.00±1.41)×106/ml、(59.80±5.29)%和(14.78±2.03)%,对照组分别为(12.00±4.12)×106/ml、(88.90±5.37)%和(5.88±1.10)%,感染组和正常对照组比较差异均有统计学意义(P均<0.01)。感染组小鼠睾丸组织出现明显的病理变化。结论雄性小鼠感染大肠埃希菌后,可导致生精细胞凋亡增加及上调Fas和FasL蛋白的表达水平;Fas和FasL在小鼠睾丸组织的高表达诱导生精细胞的凋亡,最终使小鼠精子形成减少,活动率下降,畸形率增加。大肠埃希菌感染造成生精细胞凋亡可能是导致男性不育的原因之一。Objective To explore the effects of Escherichia coli infection on the apoptosis of spermatogenic cells, and to study the expression of Fas/FasL in mice. Methods E. coli was injected directly into the bladder of an adult mouse, which mimics the ascending infection pathway. One week after injection the mice were sacrificed, and the testicular tissue was collected to detect the pathological change and apoptosis of spermatogenic cells by HE staining and TUNEL. The expression of Fas/FasL was examined in testicular tissue by immunohistochemistry. The viability, activity, number of sperms and the sperm deformity rate were measured at the same time. Results In E. coli infected group, the rate of apoptosis,thelevels ofFasand FasL expression were （18.50±1.50）%, （48.10±4. 19）% and （34.60±4.18）%, respectively, while in the control group （7.40±1.69）%, （23.50±2.66）% and （19.10±4.30）%, respectively. There was a significant difference between the two groups （P〈0.05）. The sperm number, activity and deformity rate were（6.00± 1.41） × 10^6/ml, （59.80±5.29）% and （14.78±2.03）%, respectively in the infected group. In contrast, the three parameters were （12.00± 4. 12） × 10^6/ml, （88. 90 ± 5. 37）% and （5.88 ± 1.10）%, respectively, in the normal group. There was a significant difference between the infected group and the control（P〈0.01）. A significant pathological change occurred in the testicular tissue in the infected mice. Conclusion The percentage of apoptosis and the level of Fas/FasL expression in spermatogenic cells increased significantly in male mice when infected with E. coli. The high level of Fas/ FasL expression in testicular tissue induces apoptosis in germ cells. The reduction of sperm formation and its activity, the increase of the deformities and germ cell apoptosis induced by E. coli may be one of the causes in male infertility.

关 键 词：大肠埃希菌 感染 细胞凋亡 不育 雄性小鼠 

分 类 号：R378.21[医药卫生—病原生物学]