Reddy Mallikarjuna M, Mahipal Suraneni V K, Subhashini Jagu, Reddy Madhava C, Roy Karnati R, Reddy Gorla V, Reddy Pingili R K, Reddanna Pallu
Department of Animal Sciences, University of Hyderabad, Hyderabad 500046, India.
Reprod Toxicol. 2006 Oct;22(3):493-500. doi: 10.1016/j.reprotox.2006.03.003. Epub 2006 Apr 27.
Microbial infections, localized as well as systemic, are known to cause transitive or permanent male infertility. However, the mechanisms of infection-induced infertility are largely unknown. Earlier reports showed that steroidogenesis and spermatogenesis are affected during bacterial lipopolysaccharide (LPS)-induced acute inflammation. The present study used an LPS rat model to investigate the role of oxidative stress in spermatogenesis. Intraperitoneal administration of bacterial LPS (5mg/kg body weight) to adult male albino rats elevated testicular malondialdehyde (MDA) and 4-hydroxy-2-nonenal (HNE), and decreased the activities of testicular antioxidant enzymes such as catalase, superoxide dismutase, glutathione peroxidase, and glutathione reductase. The GSH/GSSG ratio also decreased significantly. Time series analysis revealed transitory oxidative stress and expression of inflammatory mediators such as interleukin-1beta (IL-1beta), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) from 3h to 12h after LPS. Testicular expression of steroidogenic acute regulatory (StAR) protein decreased to 24h, in correlation with damage to spermatogenesis. These data are consistent with oxidative stress as a major causal factor in altered steroidogenesis, spermatogenesis, and perhaps male infertility during endotoxin-induced acute inflammation.
众所周知，局部和全身性的微生物感染会导致暂时性或永久性男性不育。然而，感染导致不育的机制在很大程度上尚不清楚。早期报告显示，在细菌脂多糖（LPS）诱导的急性炎症过程中，类固醇生成和精子发生会受到影响。本研究使用LPS大鼠模型来研究氧化应激在精子发生中的作用。对成年雄性白化大鼠腹腔注射细菌LPS（5mg/kg体重）会使睾丸丙二醛（MDA）和4-羟基-2-壬烯醛（HNE）升高，并降低睾丸抗氧化酶如过氧化氢酶、超氧化物歧化酶、谷胱甘肽过氧化物酶和谷胱甘肽还原酶的活性。谷胱甘肽（GSH）/氧化型谷胱甘肽（GSSG）比值也显著降低。时间序列分析显示，LPS注射后3小时至12小时存在短暂的氧化应激以及炎症介质如白细胞介素-1β（IL-1β）、诱导型一氧化氮合酶（iNOS）和环氧化酶-2（COX-2）的表达。类固醇生成急性调节蛋白（StAR）的睾丸表达在24小时内下降，这与精子发生受损相关。这些数据表明，氧化应激是内毒素诱导的急性炎症过程中类固醇生成改变、精子发生改变以及可能导致男性不育的主要因果因素。
