[Effects of aerobic exercise and resveratrol on the expressions of JAK2 and TGF-ß1 in renal tissue of type 2 diabetes rats].

Objective: To investigate the effects of aerobic exercise and resveratrol on janus kinase 2(JAK2) and transforming growth factor-ß1(TGF-ß1) in renal tissue of type 2 diabetes rats and its mechanism. Methods: The model of type 2 diabetic rats was established through SD rats fed high-fat diet for 5 weeks together with intraperitoneal infecting after a low dose of STZ. The rats were randomly divided into diabetic control group(DC), diabetic exercise group(DE), diabetic resveratrol group(DR), diabetic exercise and resveratrol group(DER), normal control group(NC), 12 rats in each group. Exercise-related groups performed 8 weeks treadmill exercise (20 m/min, 60 min/day). Resveratrol was administered to drug-related groups for 8 weeks (45 mg/kg, 7 day/week). Eight weeks later, we examined blood glucose concentrations, 24 h microalbuminuria(UA), serum creatinine(Scr), blood urea nitrogen(BUN), and the expressions of TGF-ß1, janus kinase 2(JAK2) and JAK2 mRNA in renal tissue. Results: After eight weeks of intervention, compared with NC group, the concentrations blood glucose, 24 h UA, Scr, BUN, the expressions of TGF-ß1, JAK2 and JAK2 mRNA were increased significantly in DC group(P＜0.05). Compared with DC group, the concentrations of blood glucose, 24 h UA, Scr, BUN, the expressions of TGF-ß1, JAK2 and JAK2 mRNA were decreased significantly in DE group, DR group and DER group(P＜0.05). Conclusion: Exercise, resveratrol and combined intervention may decrease the expressions of JAK2 mRNA, JAK2 and TGF-ß1, which further attenuate renal injury for type 2 diabetes. The renal protective effect produced by exercise and resveratrol combined intervention is better than that produced by exercise or resveratrol intervention alone.

[The role of JAK2/STAT3 signaling pathway in exercise preconditioning against myocardial apoptosis].

OBJECTIVE: To study the effects of Janus kinase 2/signal transducers and activators of transcription 3 (JAK2/STAT3) in exercise preconditioning (EP) against myocardial apoptosis. METHODS: Eighty healthy male SD rats were randomly divided into control group(C), exercise exhaust(EE) group, EP group, and EP+JAK2 inhibitor AG490(AG) group(n=20). By using 3 days intermittent treadmill exercise, the EP animal model was established, and myocardial injury was induced by exhaustive exercise on treadmill. The changes of myocardial apoptosis were evaluated by TUNEL. The expressions of Caspase-3, p-JAK2 and p-STAT3 in heart were detected by Western blot or immunohistochemistry. RESULTS: Compared with group C, myocardial apoptosis, and the expressions of Caspase-3, p-JAK2, and p-STAT3 in heart were increased significantly in group EE. Compared with group EE, myocardial apoptosis and the expression of Caspase-3 were decreased significantly, while the expressions of p-JAK2 and p-STAT3 were increased significantly in group EP. Compared with group EP, myocardial apoptosis and the expression of Caspase-3 were increased significantly, while the expressions of p-JAK2 and p-STAT3 were decreased significantly in group EP+AG. CONCLUSIONS: EP could increase the expressions of p-JAK2 and p-STAT3 and decrease the expression of Caspase-3 in heart, which further mitigate myocardial apoptosis. Hence, JAK2/STAT3 pathway may participate in EP against myocardial apoptosis.