ABSTRACT
Objective To explore the effects of hawthorn proanthocyanidins (HPC) and vitamin C (VC) on kidney protection in insulin-resistance (IR) rats. Methods The IR rats were induced by high-fat diet in order to establish the model of nephropathy in type II diabetic rats, and the high-fat feeding were continued for 2 weeks after the IR rats were made. The contents of fasting blood glucose, serum insulin, glucose and microabuminuria (mAlb) in urine were tested. Fifty IR model rats were divided into model, HPC (56 mg/kg), VC (180 mg/kg), combined application of HPC (56 mg/kg) and VC (180 mg/kg), and rosiglitazone (2 mg/kg) groups. Another 10 normal rats were selected randomly to be control group. After continuous ig administration for 20 weeks in each group, these indexs, such as the levels of fasting blood glucose (FBG), serum insulin (SI), glucose in urine (24 h), creatinine (Cr), urea nitrongen (UN), uric acid (UA), were all detected. The excretion of urinary total protein (UTP), microabuminuria (mAlb), N-acetyl-β-D-glucosaminidase (NAG) were also measured. Moreover, the histopathological microstructure of kidney was observed by light microscope. Results After modeling, the levels of FBG, SI and glucose in urine increased significantly (P < 0.01) in comparation with the control group, so does the levels of UN, Cr, UA (P < 0.01) and the excretion rates of UTP, mAlb, NAG (P < 0.01). However, all these indexs were decreased significantly (P < 0.01) after the combined use of HPC and VC, which were more notable than that in HPC and VC group (P < 0.01) and equivalent to that in rosiglitazone group. Conclusion The combined application of HPC and VC can improve the renal function of IR rats and have protective effects on kidney injury.
ABSTRACT
Objective: To explore the effect of hawthorn proanthocyanidins (HPC) and vitimin C (VC) on liver oxidative stress in insulin-resistance rats. Methods: The insulin-resistance models were prepared by high-fat diet, the weight variations of all rats were tested before and after modeling, so were the contents of fasting blood-glucose and serum insulin after modeling. The colorimetric technique was used to test the concentration of serum ALT, AST, and ALP. The rats in high-fat diet group, who were succeeded in modeling, were divided into model, HPC (56 g/kg), VC (180 g/kg), HPC (56 g/kg) + VC (180 g/kg), and rosiglitazone (122 g/kg) groups. After 12 weeks of continuous administration, these indexes, such as levels of SOD, CAT, GSH-Px, GSH, and MDA in liver homogenates and SOD, GSH-Px, Na+, K+-ATPase, Ca2+, Mg2+-ATPase, and MDA in liver mitochondria, were all tested; RT-PCR was used to test the expression of PPAR-γ mRNA; The Western blotting method was adopted to test the PPAR-γ protein expression. Results: After modeling, the body weight of rats decreased significantly (P<0.05), the concentration of blood, such as glucose, serum insulin ALT, AST, and ALP all increased significantly (P<0.01); The model group was compared with control group, the activities of SOD, CAT, GSH-Px, and GSH were significantly decreased (P<0.01), the levels of glucose, insulin, and MDA increased significantly (P<0.01) in rat liver homogenate, the activities of SOD, GSH-Px, Na+, K+-ATPase, and Ca2+, Mg2+-ATPase were significantly decreased (P<0.01) and MDA level increased significantly (P<0.01) in the liver mitochondria; PPAR-γ mRNA and protein expression decreased significantly in liver tissue (P<0.01). HPC, VC, HPC + VC, and rosiglitazone improved the above indexes, which in the HPC + VC group was better than that in the HPC group and VC group, equivalent to that in rosiglitazone group. Conclusion: Liver oxidative stress which is resulted from insulin-resistance can be improved when HPC and VC are combined.