Protective effects of nuclear factor erythroid 2-related factor 2 on whole body heat stress-induced oxidative damage in the mouse testis

Reproductive Biology and Endocrinology

ChunMei Li¹  Kazuyoshi Taya²  Gen Watanabe²  Kentaro Nagaoka²  Yuanguo Piao¹  Yi Huang¹  Yansen Li¹ 

[1] College of Animal Science and Technology, Nanjing Agricultural University, 1 Weigang Road, Nanjing, 210095, P.R. China;Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan

关键词: Mice;    Leydig cell;    Germ cell;    Oxidative stress;    Nrf2;    Whole body heat stress;   

Others  :  812448
DOI  :  10.1186/1477-7827-11-23

 received in 2013-02-03, accepted in 2013-03-17,  发布年份 2013

【 摘 要 】

Background

Whole body heat stress had detrimental effect on male reproductive function. It's known that the nuclear factor erythroid 2-related factor 2 (Nrf2) activates expression of cytoprotective genes to enable cell adaptation to protect against oxidative stress. However, it’s still unclear about the exactly effects of Nrf2 on the testis. Here, we investigate the protective effect of Nrf2 on whole body heat stress-induced oxidative damage in mouse testis.

Methods

Male mice were exposed to the elevated ambient temperature (42°C) daily for 2 h. During the period of twelve consecutive days, mice were sacrificed on days 1, 2, 4, 8 and 12 immediately following heat exposure. Testes weight, enzymatic antioxidant activities and concentrations of malondialdehyde (MDA) and glutathione (GSH) in the testes were determined and immunohistochemical detection of Nrf2 protein and mRNA expression of Nrf2-regulated genes were analyzed to assess the status of Nrf2-antioxidant system.

Results

Heat-exposed mice presented significant increases in rectal, scrotal surface and body surface temperature. The concentrations of cortisol and testosterone in serum fluctuated with the number of exposed days. There were significant decrease in testes weight and relative testes weight on day 12 compared with those on other days, but significant increases in catalase (CAT) activity on day 1 and GSH level on day 4 compared with control group. The activities of total superoxide dismutase (T-SOD) and copper-zinc SOD (CuZn-SOD) increased significantly on days 8 and 12. Moreover, prominent nuclear accumulation of Nrf2 protein was observed in Leydig cells on day 2, accompanying with up-regulated mRNA levels of Nrf2-regulated genes such as Nrf2, heme oxygenase 1 (HO-1), γ-Glutamylcysteine synthetase (GCLC) and NAD (P) H: quinone oxidoreductase 1 (NQO1)) in heat-treated groups.

Conclusions

These results suggest that Nrf2 displayed nuclear accumulation and protective activity in the process of heat treated-induced oxidative stress in mouse testes, indicating that Nrf2 might be a potential target for new drugs designed to protect germ cell and Leydig cell from oxidative stress.

【 授权许可】

   
2013 Li et al.; licensee BioMed Central Ltd.

【 图 表 】

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