| Aims:To observe the changes of exercise in the cold on blood glucose,insulin and blood lipid,the protein expression of gastrocnemius p38 MAPK,PGC-1 α,FNDC5,and inguinal fat UCP1,Betatrophin,the activities of LPL and ATGL in obese rats.To explore the effects of exercise in the cold on improving insulin sensitivity and browning of white tissue and related regulatory factors in obese patients.Provide theoretical basis and methods for the prevention and treatment of obesity and type 2diabetes.Methods:64 SD rats with a 9-week high-fat and high-sugar diet to establish an obesity model and Randomly divided into 8 groups:normal temperature sedentary group(NTS),normal temperature exercise(NTE),continuous low temperature sedentary group(CLS),continuous low temperature exercise(CLE),acute low temperature sedentary group(ALS),acute low temperature exercise group(ALE),intermittent low temperature sedentary group(ILS)and intermittent low temperature exercise group(ILE).The normal temperature environment is 23℃±2℃,the low temperature environment is 3℃±1℃,the relative humidity is 50-60%;Intermittent low temperature exposure was 4h/d,continuous low temperature exposure was to live in a low temperature environment all day,acute intermittent low temperature exposure was to be exposed to low temperature for 4h at the end of the experiment,and the rest of the time to live at room temperature.All the exercise groups exercised for 1h on the second day,and the exercise was divided into two sections,each section was 30 min,the interval was 10 min,the running speed was 25m/min,and the slope was 0°.The rats were weighed and recorded daily during the experiment to record their weight and food intake.Sampling on the 5th week,four blood lipids,free fatty acids,blood glucose,and serum insulin were measured,and the insulin resistance index was calculated.Western-blot was used to detect the protein expression of gastrocnemius p38 MAPK,PGC-1 α,FNDC5,and inguinal fat UCP1,Betatrophin,the activities of LPL and ATGL.SPSS 22.0 was used for statistical analysis of the experimental results,ANOVA analysis was used between groups,Pearson correlation analysis was used among various factors,P < 0.05 was significant,P < 0.01 was verysignificant.Results:(1)Compared with the NTS group,the NTE group’s obese rats’ diet and weight were significantly reduced(P <0.05),the CLS group’s diet increased significantly(P<0.05),and the visceral fat rate was significantly reduced(P <0.01).CLS,ALS,ILS The increase in brown fat rate of obese rats in the group was statistically significant(P <0.05,P <0.01).Compared with the NTE group,the diet and brown fat rate of the obese rats in the CLE group increased significantly or very significantly(P<0.05,P<0.01),the body weight decreased significantly(P<0.05),and the subcutaneous fat rate in the ALE group decreased significantly(P<0.05).(2)Compared with the NTS group,FINS in the ALS group increased significantly(P <0.05),and FBG and HOMA-IR in the NTE and ALS groups decreased significantly(P <0.05).Compared with the NTE group,FINS,FBG,HOMA-IR in the ALE group decreases were statistically significant(P <0.05,P<0.01).In terms of blood lipids,compared with the NTS group,CHO and TG in the NTE group decreased significantly(P <0.05),and HDL-C in the NTE and CLS groups significantly increased.(P <0.05),serum LDL-C in obese rats in NTE,CLS,and ILS groups decreased significantly(P <0.05).Compared with NTE group,serum HDL-C in obese rats in CLE and ILE groups significantly increased(P <0.05).(3)Compared with the NTS group,the expression of p38 MAPK,PGC-1α,and FNDC5 protein in the CLS and ILS groups was statistically significant(P<0.05,P<0.01);compared with the NTE group,the p38 MAPK protein expression in the CLE group Significantly up-regulated(P<0.05),upregulation PGC-1α protein expression in the CLE,ALE,and ILE groups was statistically significant(P<0.05,P<0.01),and FNDC5 protein expression in skeletal muscle of obese rats in the CLE and ILE groups was statistically increased Significance(P<0.05,P<0.01).(4)Compared with the NTS group,the upregulation of UCP1 protein in other groups was statistically significant(P < 0.05,P < 0.01),and the expression of Betatrophin protein in the NTE,ALS,and ILS groups was significantly or very significantly down-regulated(P< 0.05,P<0.01),the LPL and ATGL activities of the ILS group were significantly increased(P<0.05).Compared with the NTE group,the up-regulation of UCP1 protein expression and the down-regulation of Betatrophin protein expression in the CLE and ILE groups were statistically significant(P<0.05,P<0.01),LPL for CLE group,ATGL for ILE group activity significantly increased(P<0.05).(5)Correlation analysis results showed that Betatrophin in inguinal fat and UCP1 protein expression in obese rats were negatively correlated(r =-0.402,P<0.01)after 5 weeks of low temperature environmental exercise intervention,and negatively correlated with LPL activity changes(r =-0.298,P<0.05),negatively correlated with changes in ATGL activity(r =-0.565,P < 0.01),and positively correlated with HOMA-IR(r = 0.374,P<0.01).Conclusions:(1)All three types of exercise in the cold can effectively promote the browning of white tissue in obese rats,increase brown fat,reduce visceral and subcutaneous fat,and achieve weight loss.Among them,intermittent cold temperature exercise and sustained cold temperature exercise are the most effective.(2)The way of acute cold temperature exercise to temporarily increase the body’s insulin sensitivity is of little significance in the clinical treatment of type 2diabetes,and intermittent and sustained cold temperature environmental exercise can reduce blood lipid levels,increase free fatty acid and glucose intake in obese rats for a long time,Improving insulin sensitivity has a certain effect on the prevention and treatment of type 2 diabetes.(3)Cold temperature environmental exercise promotes browning of white fat,inhibits the expression of Betatrophin,increases the activity of LPL and ATGL by activating the p38 MAPK signal pathway,thereby improving the effect of improving glucose and lipid metabolism in obese bodies. |
