龟龄集对900 MHz手机电磁辐射致大鼠睾丸氧化损伤和Prdx2蛋白表达的影响

Guilingji Capsules reduce 900 MHz collphone electromagnetic radiation-induced testicular oxidative damage and downregulate Prdx2 protein expression in the rat testis

目的:探讨900 MHz手机频率电磁辐射对大鼠睾丸氧化损伤以及过氧化物酶2(Prdx2)蛋白表达的影响,并探讨龟龄集对其作用机制。方法:将50只清洁级健康SD雄性大鼠随机均分为五组(各10只),分别为:假辐射组、4 h辐射组、8 h辐射组、4 h龟龄集胶囊组、8 h龟龄集胶囊组。假辐射组辐射0 h,余组分别于900 MHz电磁辐射(370μW/cm^2)下暴露4 h和8 h,持续15 d,4 h龟龄集胶囊组和8 h龟龄集胶囊组辐射后灌胃龟龄集混悬液,其它3组灌胃纯净水。实验结束后处死取材。HE染色观察大鼠睾丸组织病理形态,透射电镜观察睾丸组织超微结构的变化,TBA法检测大鼠血清谷胱甘肽(GSH)、超氧化物歧化酶(SOD)、丙二醛(MDA)指标变化,免疫组化和Western blot技术检测Prdx2蛋白的表达。结果:与假辐射组比较,辐射组大鼠睾丸组织形态学及超微结构均有不同程度的改变;辐射4 h组GSH含量为69.58±4.18、SOD活性为172.29±10.98、MDA含量为9.84±1.03,辐射8 h组GSH含量为66.17±8.45、SOD活性为148.91±8.60、MDA含量为11.22±2.13,辐射组GSH含量、SOD活性显著下降且随时间延长下降越明显,MDA含量增多且随时间延长增加越明显;假辐射组大鼠睾丸组织Prdx2蛋白表达量为0.44±0.09,辐射4 h和8 h组大鼠睾丸组织Prdx2蛋白表达量为0.25±0.08、0.20±0.07,中药4 h和8 h组大鼠睾丸组织Prdx2蛋白表达量为0.40±0.07、0.41±0.07,辐射组大鼠睾丸组织Prdx2蛋白表达量随时间延长而降低且低于假辐射组和中药干预组,差异有统计学意义(P<0.05)。结论:手机电磁辐射可导致睾丸组织超微结构损伤,龟龄集可改善其损伤,推测其作用机制可能与影响大鼠睾丸Prdx2蛋白表达和减轻氧化损伤相关。

Objective: To investigate the relationship of electromagnetic radiation(EMR) from 900 MHz cellphone frequency with testicular oxidative damage and its influence on the Prdx2 protein expression in the rat testis, and to explore the mechanism of Guilingji Capsules(GC) alleviating oxidative damage to the testis tissue. Methods: Fifty healthy SD male rats were randomly divided into five groups of equal number, sham-EMR, 4-h EMR, 8-h EMR, 4-h EMR+GC and 8-h EMR+GC and exposed to 900 MHz EMR(370 μW/cm^2) for 0, 4 or 8 hours daily for 15 successive days. The rats of the latter two groups were treated intragastrically with GC suspension and those of the first three groups with pure water after exposure to EMR each day. After 15 days of exposure and treatment, all the rats were sacrificed and their testis tissue collected for observation of the histomorphological and ultrastructural changes by HE staining and transmission electron microscopy, measurement of the levels of serum glutathione(GSH), superoxide dismutase(SOD) and malondialdehyde(MDA) with thiobarbiuric acid and determination of the Prdx2 protein expression by immunohistochemistry and Western blot. Results: Compared with the rats in the sham-EMR group, those in the 4-h and 8-h EMR groups showed different degrees of histomorphological and ultrastructural changes in the testis tissue, significantly decreased levels of GSH([80.62 ± 10.99] vs [69.58 ± 4.18] and [66.17 ± 8.45] mg/L, P < 0.05) and SOD([172.29 ± 10.98] vs [158.92 ± 6.46] and [148.91 ± 8.60] U/ml, P < 0.05) and increased level of MDA([7.51 ± 1.73] vs [9.84 ± 1.03] and [11.22 ± 2.13] umol/ml, P < 0.05), even more significantly in the 8-h than in the 4-h EMR group(P < 0.05). In comparison with the sham-EMR group, the expression of the Prdx2 protein was markedly downregulated in the 4-h and 8-h EMR groups(0.56 ± 0.03 vs 0.49 ± 0.03, 0.21 ± 0.01, P < 0.05), but again upregulated in the 4-h and 8-h EMR+GC groups(0.55±0.03 and 0.37±0.04)(P < 0.05). Conclusion: Electromagnetic radiation from cellphones can cause ultrastructural damage to the testis tissue of male rats, while Guilingji Capsules can alleviate it, presumably by upregulating the Prdx2 protein expression in the testis tissue and reducing testicular oxidative damage. Natl J Androl, 2020, 26(10): 926-933.