Regulatory effect of curcumin on renal apoptosis and its mechanism in overtraining rats / 中国应用生理学杂志

OBJECTIVE@#To study the effects and mechanisms of curcumin alleviating oxidative stress induced by overtraining and inhibiting renal apoptosis in rats.@*METHODS@#Male Wistar rats of 7 weeks old were divided into control group (C group, 12), overtraining group (OM group, 11), curcumin + overtraining group (COM group, 14). Group C did not undergo any exercise intervention. Rats in OM group and COM group underwent 8-week incremental load swimming training. During the training, the COM group was treated with curcumin at the dose of 200 mg/(kg·d) in the volume as 5 ml/kg by intragastric administration, and the other groups was treated with an equal volume of 0.5% carboxymethylcellulose. Twenty-four hours after the last training, renal histopathological changes were observed by light microscopy, related biochemical indicators in blood and renal tissue were detected.@*RESULTS@#The results showed that after 8 weeks of incremental load swimming training, the renal tissue structure of group C was normal under light microscope; histopathological changes were observed in OM group; COM group was significantly relieved compared with OM group. Compared with group C, serum levels of corticosterone (Cor), creatinine (Cr) and blood urea nitrogen (BUN) in OM group were increased (0.05), while the expression of heme oxygenase-1 (HO-1) was decreased (<0.05), total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) activity were decreased (<0.01), malondialdehyde (MDA) concentration was increased (<0.01); the renal apoptosis was increased (<0.01), the expression of anti-apoptotic B cell lymphoma-2 protein (Bcl-2) was decreased (<0.01), and the expression of proapoptotic Bcl-2 associated X protein (Bax) was increased (<0.01). Compared with the OM group, Cor level was decreased (<0.01) in the COM group, T level was increased (<0.01), Cr and BUN levels were lower (<0.05); the expression of Nrf2 and HO-1 were increased (<0.05), T-AOC and SOD activity were increased (<0.01), MDA concentration was decreased (<0.05); the renal apoptosis was decreased (<0.05), the expression of Bcl-2 was increased (<0.05), and the expression of Bax was decreased (<0.01). The trend of testosterone/corticosterone ratio between groups was consistent with testosterone change, and the change trend of Bcl-2/Bax ratio was consistent with the change of Bcl-2.@*CONCLUSIONS@#The 8-week incremental load swimming training triggered excessive training in rats, aggravated oxidative stress and accelerated renal apoptosis, leading to pathological changes and dysfunction of kidney. Curcumin can up-regulate expression of Nrf2 and HO-1, effectively alleviates oxidative stress induced by overtraining, thereby increasing Bcl-2 expression, decreasing Bax expression, inhibiting renal apoptosis and protecting renal tissue structure and function properly.

Effects and mechanisms of 6-week intensive training on renal function in rats / 中国应用生理学杂志

OBJECTIVE@#To study the effect of 6-week intensive training on renal function in rats and the mechanism of exercise-induced proteinuria.@*METHODS@#Thirty-six male SD rats, aged 6 weeks, were divided into two groups, including a control group(C,=12)and an overtraining group(M,=24). After the rats adapted to feeding for 4 d, group C did not carry out any exercise, and the M group did 6-week of increasing load swimming, 6 days a week, once a day. Started with the load of 1%weight at the beginning of the 4 week,and gradually increased (to 6% weight). Took a single urine from both groups 30 min after the end of the training. Blood was taken from the main ventral vein, and the bilateral kidneys were to be tested. The levels of tested urine protein, microalbumin and neutrophil gelatinase associated lipocalin(NGAL) was determined by using enzyme linked immunosorbent assaytest. The content of urine creatinine was tested with alkaline picric acid method,. The serum levels of colorimetric method to determine serum creatinine and urea nitrogen were determined by colorimetric method. The expression of Nephrin in renal tissue was detected by Western blot and the radioimmunoassay was used to test serum testosterone, corticosterone and renin-angiotensin system related index.@*RESULTS@#Compared with group C, the serum testosterone/cortisone(T/C) of group M was decreased significantly (<0.01). The urine total protein(TP), microalbumin (mAlb), microalbumin/creatinine (mAlb/CRE), NGAL, blood urea nitrogen (BUN) and serum creatinine(SCr) were increased significantly (<0.01). The abnormality of glomerular structure was obvious, and the paller scores were higher. The protein expression of Nephrin was obviously down decreased (<0.01). The renin activity (Ra) and angiotension Ⅱ (Ang Ⅱ) in renal and circulating blood were decreased significantly (<0.01).@*CONCLUSIONS@#The effects of 6-week intensive training on renal function in rats and the mechanism of exercise-induced proteinuria may be that overtraining can induce the continuous excitation of Reninrenin activity in renal and circulating blood, down-regulated the expression of Nephrin, lead to abnormality of renal structure and function, and proteinuria.

Effects of aerobic exercise combined with chlorella pyrenoidos of disintegrated cell wall on some indicators of lipid metabolism in rats with high-fat diet / 中国应用生理学杂志

OBJECTIVE@#To study the effects of aerobic exercise combined with chlorella pyrenoidos of disintegrated cell wall on the lipid metabolism in rats with high-fat diet.@*METHODS@#Fifty-five male Wistar rats were subjected to adaptive feeding for 4 days and weight-free swimming training for 3 days, 20 min/d. After eliminating 5 rats that were not suitable for swimming training, the other rats were randomly divided into 5 groups according to their body weight:control group (C group), high fat diet group (H group), high-fat diet + chlorella group(HC group), high fat diet + aerobic exercise group (HM group), high fat diet + chlorella + aerobic exercise group (HMC group), 10 in each group. The HM and HMC group were subjected to 60 min/d swimming training for 6 weeks with non-weight-bearing. Group C were fed regular diet. The other groups were fed with high-fat diet, the rats in group HC and HMC were intragastrically treated with chlorella pyrenoidos of disintegrated cell wall at the dose of 3.9 g/(kg·d), the volume was 5 ml/kg, and the other groups are given equivalent saline. The Lee's index and biochemical indexes of blood and liver were measured after 6 weeks.@*RESULTS@#Compared with group C, Lee's index, serum levels of free fatty acids(FFA), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-c), liver FFA and interleukin-10 (IL-10) were increased significantly (<0.01), the serum level of high-density lipoprotein cholesterol (HDL-c) was decreased significantly (<0.01) in group H. Compared with group H, Lee's index, serum FFA, IL-6, TNF-α, TC, TG, LDL-c, liver FFA and IL-10 were decreased significantly (<0.05 or <0.01), serum level of HDL-c was increased significantly (<0.05 or <0.01) in group HC, HM and HMC. Compared with group HC and HM, Lee's index, serum FFA, IL-6, TNF-α, TC, TG, LDL-c, liver FFA and IL-10 were decreased significantly (<0.05), serum level of HDL-c was increased significantly (<0.05) in group HMC.@*CONCLUSIONS@#Aerobic exercise and chlorella pyrenoidos of disintegrated cell wall can improve lipid metabolism in rats with high-fat diet and reduce the lipid toxicity caused by obesity. Joint intervention is more effective than single intervention.