[Protective effect of lycium barbarum polysaccharides against heat stress-induced germ cell apoptosis in rats and its mechanism].

OBJECTIVE: To investigate the protective effect of lycium barbarum polysaccharides (LBP) against heat stress-induced apoptosis of germ cells in rats and its action mechanism. METHODS: Ninety male Sprague-Dawley rats were randomly divided into five groups of 18 each: control, heat stress (HS), high-dose LBP, median-dose LBP and low-dose LBP. The rats of the three LBP groups were given LBP by intragastric administration at 100 mg/(kg x d), 50 mg/(kg x d) and 10 mg/(kg x d) respectively for 14 days, and on the 15th day they, together with those of the HS group, were exposed to a heat of 43 degrees C for 30 minutes. At 24 h, 48 h and 7 d after heat stress, the animals were killed by cervical dislocation, followed by observation of the apoptotic germ cells by TUNEL, determination of the expression of Caspase-3 by immunohistochemistry and detection of cytochrome C in the cytosol by ELISA. RESULTS: Compared with the HS group, the three LBP groups showed statistically significant decreases in the apoptosis index (P<0.05), the expression level of Caspase-3 in germ cells (P<0.05) and the concentration of cytochrome C in the cytosol (P<0.05). CONCLUSION: LBP can inhibit cytochrome C release from mitochondria, decrease the expression of Caspase-3 and hence reduce the apoptosis of germ cells. It thus can be deduced that LBP can protect germ cells against apoptosis via the mitochondrial pathway.

[Experimental study on antioxidant and calcium channel blockade preventing testicular fibrosis in rats].

OBJECTIVE: To investigate the preventive effect of antioxidant and calcium channel blockade on testicular fibrosis in rats, and to explore the ideal drug for preventing it. METHODS: Eighty Wistar rats were divided into a control group (Group A, n = 10), a treatment group (Group B, n = 57) and a testicular fibrosis model group (Group C, n = 13). And the treatment group was further divided into a higher dosage group (Group a, n = 20), a medium dosage group (Group b, n =20) and a lower dosage group (Group c, n = 17). Testicular fibrosis was duplicated with altered Wang Tao's method. From the second day of the first immunization, the higher dosage group was given antioxidant vitamins 90 mg/(kg x d) and verapamil 50 mg/(kg x d), the medium dosage group antioxidant vitamins 90 mg/(kg x d) and verapamil 25 mg/(kg x d), and the lower dosage group antioxidant vitamins 90 mg/(kg x d) and verapamil 12.5 mg/(kg x d), all for 150 days. The control and the model groups received no treatment. The sperm count, sperm deformity rate, testis length and seminiferous tubule intradiameter were measured, and the changes of the testis interstitial substance and spermatogenic cells were observed by light microscope and transmission electron microscope. RESULTS: Testicular fibrosis was significantly prevented by the higher- and medium-dosage treatment in the rats. In the higher dosage group, the intradiameter of the seminiferous tubules and the thickness of the limiting membrane were almost the same as in the control. In the lower dosage group the thickness of the limiting membrane was thicker and the damage to the spermatogenic cells was heavier than in the control, but the pathological changes of the testis structure was lighter than in the model group, in which Hyperplasia and fibroblast increase in the interstitial substance were significant, interstitial mast cells and peritubular mast cells increased, the thickness of the limiting membrane of the seminiferous tubules seriously thickened, and the damage to the spermatogenic cells was severe. CONCLUSION: Testicular fibrosis in rats can be significantly prevented by antioxidant and calcium channel blockade.