RESUMO
Objective To explore the effects of α-keto acid combined with low protein diet on oxidative stress and electrolyte levels in patients with diabetic nephropathy. Methods Ninety-eight cases with type 2 diabetic nephropathy were randomLy divided into the treatment group(low-protein diet with α-keto acid 1 tablet,n=58) and the control group(normal protein intake,n=40). The 24 h urinary albumin excretion rate,glomerular filtra-tion rate ,serum oxidative stress (SOD ,MDA ,AOPPs) and electrolyte levels were measured before and after treatment. Results After 24 weeks of treatment,the 24 h urinary albumin excretion rate of DN patients in the treatment group was significantly lower than that before treatment and the control group (P < 0.05). However, there was no significant change in the glomerular filtration rate of the patients. Compared with the control group , the serum SOD activity of DN patients was significantly increased and the levels of MDA and AOPPs were decreased(P < 0.05)after 24 weeks of treatment. Simultaneously,the levels of serum potassium and phosphorus in the treatment group was decreased ,while the levels of calcium and magnesium were improved (P < 0.05). Conclusion α-keto acid combined with low protein diet can significantly reduce the urinary albumin excretion rate,improve the body′s antioxidant activity,and maintain serum electrolytes balance.
RESUMO
Objective To observe the muscle wasting in diabetic kidney disease (DKD) model of type 2 and non-obese diabetes mellitus in Goto-Kakizaki (GK) rats,and to evaluate the effect of lowprotein diet supplemented with α-keto acids on muscle wasting.Methods Forty-five male 24-weekage GK rats were randomly divided into three groups:normal protein diet group (22％ casein diet,NPD),low protein diet group (6％ casein diet,LPD) and LPD + α-keto group (5％ casein + 1％ α-keto,Keto).Fifteen gender-and age-matched Wistar rats were served as the control group (CTL).The living condition of GK rats was observed and body weight was measured once a week.Urine albumin,serum glucose,lipids,albumin,creatinine and urea nitrogen were measured at the age of 24,32,40,48 weeks.Soleus muscle at the age of 48-week was observed to calculate the muscle size with software.Expressions of atrogin-1,MuRF-1 and MyoD,myogenin were examined by Q-PCR and Western blotting.Results Compared with the CTL group,NPD,LPD,Keto groups had lower body weight [(317.90± 13.81),(330.38±11.96),(390.44±12.25) g vs (429.43± 16.85) g,all P ＜ 0.05],higher urine albumin [(14.36±5.52),(8.12±4.61),(5.58±3.50) mg/24 h vs (0.61±0.16) mg/24 h,all P ＜ 0.05],higher serum creatinine [(81.50±7.88),(66.32±8.36),(63.44±8.21) μmol/L vs (24.43±6.15) μmol/L,all P ＜0.05] and urea nitrogen [(7.53±1.05),(5.63±1.40),(5.54±0.97) mmol/L vs (2.98±0.62) mmol/L,all P ＜0.05].The cross-sectional area of soleus muscle fibers was larger in CTL group.Compared with CTL group,the expression levels of atrogin-1 and MuRF-1 increased significantly (all P ＜ 0.05),and of MyoD and myogenin decreased significantly in NPD,LPD,Keto groups (all P ＜ 0.05).In Keto group after 40 weeks,muscle wasting was improved compared with NPD and LPD group [body weight (381.62± 15.82) g vs (331.50±17.58),(326.60± 13.43) g,all P ＜ 0.05],cross-sectional area of soleus muscle increased,levels of urine albumin,serum creatinine and urea nitrogen decreased (all P ＜ 0.05),the protein expressions of atrogin-1 and MuRF-1 decreased,and myogenin and MyoD were higher as compared to CTL group (all P ＜ 0.05).There were no significant differences between NPD and LPD group.Conclusions In DKD condition,protein degradation in the skeletal muscle is accelerated,the genes which control muscle atrophy are activated,and proliferation and differentiation of the muscle satellite cells are impaired.Low-protein diet supplemented with α-keto acids can improve muscle wasting induced by DKD.