Effects Of Creatine Supplementation On Glucose Metabolism As Well As Related Proteins Of Autophagy And Endogenous Creatine Synthesis In High-fat Diet Mice

Objective:The purpose of this study was to study the effects of creatine supplementation on body weight,glucose tolerance,insulin tolerance,tissue morphology,glucose metabolism,autophagy and endogenous creatine synthesis-related proteins in high fat diet mice.To determine whether creatine supplementation can improve the effects of high fat diet on glucose metabolism,autophagy and endogenous creatine synthesis-related proteins in mice.The purpose of this study is to provide theoretical basis for creatine to improve abnormal glucose metabolism and obesity.Methods: Twenty-four 6-week-old male C57 mice were randomly divided into control group,high-fat group and high-fat creatine group according to their body weight.After fasting for 16 hours,glucose tolerance test was performed,and the blood glucose values of 15 min,30min,60 min and 120 min were measured after fasting and after glucose injection.Insulin tolerance test was performed after fasting for 4 hours,and the blood glucose values of 15 min,30min,60 min and 90 min were measured after fasting and after insulin injection.After the establishment of the model,the liver,kidney,gastrocnemius muscle,soleus muscle,brown fat tissue,white fat tissue and other tissues were taken for appearance observation,HE staining and Oil Red O staining,and the tissue protein expression was determined by Western Blot.The experimental results were analyzed by SPSS19.0,and the data were expressed in the form of mean±standard deviation.The difference was significant(P<0.05),and the difference was extremely significant(P<0.01).Results:1.The high fat group reached the obesity standard in the fourth week,and the creatine group reached the obesity standard in the sixth week.The body weight of the creatine group was lower than that of the high fat group.2.Glucose tolerance test: compared with the control group,the blood glucose values of 15 min,30min and 60 min in the high fat group were significantly higher than those in the control group.30 min in creatine group was significantly higher than that in control group only after fasting and after glucose injection,and the blood glucose values of 15 min,30min and 120 min in creatine group after glucose injection were significantly lower than those in hyperlipidemia group.3.Insulin tolerance test: compared with the control group,the blood glucose value at each time point in the high fat group was significantly higher than that in the control group,and the 15 min,30min,60 min and 90 min in the creatine group were significantly lower than those in the high fat group after insulin injection.4.HE staining results: compared with the control group,the volume of lipid droplets in adipose tissue and almost all cells in the high fat group was significantly larger than that in the control group.Compared with the high fat group,the lipid droplet volume of adipocytes in the creatine group decreased significantly.5.The results of oil red O staining experiment: compared with the control group,the brown adipose tissue and liver of the high fat group were dark red and the lipid content was higher;compared with the high fat group,the color of the creatine group was lighter and the lipid content was lower.6.Western blot experiment: compared with the control group,LC3 II of brown fat decreased in the high-fat group(P<0.05);Soleus muscle P62,AKT,PAKT increased(P<0.05);AKT and PAKT increased in gastrocellus muscle(P<0.05).Brown fat GLUT4 increased in the creatine group compared to the control group(P<0.05);White fat ATGL increases(P<0.05);Soleus muscle LC3 II decreased(P<0.05);BECN1,SLC6A8,AKT,PAKT increased(P<0.05),LC3 II decreased(P<0.05);GAMT and GATM in liver decreased(P<0.01).Brown fat GAMT increased in the creatine group compared to the high-fat group(P<0.05);White fat PAKT decreased(P<0.05),ATGL increased(P<0.05);In soleus muscle,P62,GATM,AKT and PAKT decreased(P<0.05),and GAMT increased(P<0.05).LC3 II and SLC6A8 decreased in gastritis muscle(P<0.05),while GATM,IGFIR and PIRS612 increased(P<0.05).Conclusion:1.Creatine supplementation can delay the occurrence of obesity induced by high-fat diet,and its effect will be weakened with time.2.Creatine supplementation can improve glucose tolerance and insulin resistance caused by high-fat diet to some extent,and then improve glucose metabolism.3.High-fat diet causes abnormal autophagy of brown fat and soleus muscle.Supplementation of creatine can reduce the level of autophagy of soleus muscle,gastrocnemius muscle and kidney,increase the level of autophagy of white fat,and reduce the adverse effects of high-fat diet.4.High-fat diet can induce abnormal endogenous creatine synthesis and transport in different tissues.Creatine supplementation can improve the abnormal endogenous creatine synthesis and transport in skeletal muscle caused by high-fat diet and inhibit endogenous creatine synthesis in liver.