To investigate the relationship between hypoxia and epididymal dysfunction and the mechanism of epididymal dysfunction in rats with left-side varicocele, a total of 45 male Wistar rats were randomly divided into three groups in average. The expression of hypoxia-inducible factor-1α (HIF-1α) was detected by Western blot and immunohistochemical analysis respectively. HIF-1α was expressed in the experimental group, and the positive rate was significantly higher than that of either the sham or the control group (P < 0.05). The apoptosis index (AI) of epididymal epithelium was higher in the experimental group (7.25 ± 2.56) than that in either the sham (0.52 ± 0.57, P < 0.01) or the control group (0.08 ± 0.13, P < 0.01). Additionally, the levels of sialic acid and carnitine were lower in the experimental group than that in either the sham or the control group (P < 0.05) and were significantly negatively correlated with HIF-1α expression (r = -0.620, P = 0.014, and r = -0.610, P = 0.016 respectively). It is concluded that left-side varicocele could cause epididymal hypoxia and epididymal dysfunction. Moreover, HIF-1α maybe act as useful factor to predict germ cell apoptosis in varicocele.

This study was aimed at investigating the expression of brain-derived neurotrophic factor (BDNF) in mesenchymal stem cells (MSCs) modified with recombinant lentivirus bearing BDNF gene. Lentivirus vectors bearing BDNF gene were constructed. MSCs were isolated from rats and cultured. The lentiviral vectors containing BDNF gene were transfected into the MSCs, and BDNF gene and protein expressions were monitored with enhanced green fluorescent protein (EGFP). RT-PCR and Western blot were used to measure gene and protein expressions, respectibvely in MSCs, MSCs-EGFP and MSCs-EGFP-BDNF groups. Green fluorescence assay confirmed successful transfection of BDNF gene recombinant lentivirus into MSCs. RT-PCR and Western blot revealed that BDNF gene and protein expressions in the MSCs-EGFP-BDNF group were significantly higher than that in MSCs group and MSCs-EGFP group. There were no statistically significant differences in gene expression between MSCs and MSCs-EGFP groups. MSCs can over-express BDNF when transfected with recombinant lentivirus bearing BDNF gene.