Abstract：Objective To study the effect of JAK2/STAT3 signaling pathway in testis on male reproduction via detecting the serum leptin level and the expression of JAK2/STAT3 protein in testis of the diet-induced obese mice. Methods A total of 48 C57bl/6 male mice, 5 weeks old, were randomly divided into the control group (n=12) and the experimental group (n=36). The control group was fed with standard diet, while the experimental group received high-fat diet. After 19 weeks of feeding, the mice of the experimental group were divided into diet-induced obesity (DIO) group and diet-induced obesity resistance (DIO-R) group by weight gain. Inferior caval vein blood, testis, retroperitoneal fat and epididymal fat were collected and weighted. Serum leptin level was detected by ELISA kit. The protein expression of JAK2, p-JAK2, STAT3 and p-STAT3 in testis were detected by Western blot. Results The absolute weight and relative weight of retroperitoneal and epididymal fat were significantly higher in the DIO group and the DIO-R group than in the control group (all P<0.05), but were not significantly different between the DIO group and the DIO-R group (all P>0.05). The serum leptin level was significantly higher in the DIO group and the DIO-R group than in the control group (P<0.05), but was not significantly different between the DIO group and the DIO-R group (P>0.05). The expression of p-JAK2 and p-STAT3 protein was significantly lower in the DIO group than in the control group (both P<0.05). The expression of p-JAK2 protein in the DIO group was lower than that in the DIO-R group (P<0.05), but there was no statistically significant difference in the expression of p-STAT3 protein between the DIO group and the DIO-R group (P>0.05). Conclusions Diet-induced obesity can lead to elevated serum leptin level and decreased expression of JAK2/STAT3 protein in testis in male mice.
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2018, Vol. 25 
