| Aims: To observe the effects of lipid and 12,13-Di Home in blood,changes of triglyceride(TG),free fatty acid(FFA),expression of 12,13-di Home synthesis and transport-related proteins and m RNA in interscapular fat and regulation of insulin sensitivity in nutritive obese rats after long-term exercise in cold,the paper reported the effects of 12,13-DiHOME on lipid metabolism and insulin sensitivity after exercise in cold,thus providing a theoretical basis for obesity prevention.Methods: Nutritional obesity rat model was established by 45% high fat diet at 8weeks.Forty-eight obese rats were randomly divided into 6 groups: Control group in Normal temperature(NC),Exercise group in Normal temperature(NE),Control group sustainable in cold(CC),Exercise group sustainable in cold(CE),Control group sustainable in cold with caloric restriction group(CCR)and Exercise group sustainable in cold with caloric restriction group(CER),and then received cold environment exercise intervention for 5 weeks.The temperature of the normal group was 24℃-26℃,and the temperature of the low group was 3℃-4℃.Rats in the exercise group received one endurance training every other day,running speed was 25m/min,30min/ group,2 groups /d,and then the interval between the groups was10 min,and the exercise lasted for 5wk.The CCR and CER groups were calorie-controlled according to the caloric intake of NC and NE groups.During the intervention,body weight and intake of all rats were recorded.After 5 weeks of study,oral glucose tolerance(OGTT)and insulin tolerance(ITT)were measured.After fasting,the blood was collected from the abdominal aorta,and the perirenal,epididymis fat and interscapular fat were dissected.The concentrations of four lipids in blood,plasma and interscapular fat free fatty acid(FFA)and 12,13-Dihome content were detected.The gene and protein expressions of Ephx1/2,CD36 and FATP1 in interscapular fat were detected by q RT-PCR and Weatern-blot.Graph Pad Prism 8.0.2was used for chart drawing and graph analysis,and SPSS 25.0 was used for statistical analysis of the data.One-way ANOVA was used between the groups,and Pearson correlation analysis was used between each factor.P<0.05 indicated significant difference,and P<0.01 indicated very significant difference.Results:1)Compared with NC group,body weight and visceral fat percentage in NE,CC,CE,CCR and CER groups were significantly decreased(P< 0.01);Compared with NE group,the visceral fat percentage in CC group was significantly decreased(P<0.05),and the visceral fat percentage in CE,CCR and CER were significantly decreased(P< 0.01).Compared with CC group,the percentage of visceral fat in CCR and CER groups was also significantly decreased(P< 0.01).Temperature,exercise and food intake all had significant effects on body weight,Lee’s index and visceral fat percentage,but there was no interaction between these factors.2)Compared with NC group,serum FFA,high-density lipoprotein-cholesterol(HDL-C)and plasma 12,13-Di Home in CC,CE,CCR and CER groups were significantly increased(P < 0.01),and plasma TG was significantly decreased(P <0.01).LDL-C in CER group was significantly lower than that in NE and CCR groups(P< 0.01).CER group was significantly lower than CC group(P< 0.05).The results of three-factor analysis showed that the effects of temperature on TG,FFA and 12,13-DiHOME were extremely significant(P< 0.01),the interaction of temperature and exercise on FFA was significant(P< 0.01),and the interaction of exercise and food intake on TG and LDL-C was significant(P< 0.05).3)Compared with NE group,TG concentration in interscapular fat in NC,CC,CE,CCR and CER groups was significantly increased(P< 0.01);Compared with NC group,FFA content in interscapular fat in CC,CE,CCR and CER groups was significantly increased(P < 0.05 in CER group,P < 0.01 in CC,CE and CCR groups).Compared with CC group,TG in interscapular fat in CCE group,FFA in FFA group and CER group were significantly decreased(P < 0.01),and FFA in CER group was significantly higher than that in CCR group(P < 0.01).Compared with NC and NE groups,the contents of 12,13-Di Home in interscapular fat in CC,CE,CCR and CER groups were significantly increased(P < 0.01).4)Compared with NC group,the m RNA expressions of FATP1,Ephx1 and Ephx2 in NE group were significantly increased(Ephx1 P< 0.05,FATP1 and Ephx2 P< 0.01),and the m RNA expressions of CD36,FATP1,Ephx1 and Ephx2 in interscapular fat in CC and CCR groups were significantly increased(P< 0.01).Compared with NE,the m RNA expressions of CD36 and Ephx2 in CE group were significantly increased(P <0.01),and the m RNA expressions of FATP1,Ephx1 and Ephx2in CER group were significantly increased(P < 0.01).Compared with CE group,the m RNA expression of CD36 and FATP1 in interscapular fat in CER group was significantly increased(P <0.05,P < 0.01).Three-factor analysis showed that temperature significantly affected the m RNA expression of CD36,Ephx1 and Ephx2(P< 0.01),while Fat P1 was affected by exercise and feeding(P< 0.01),and exercise also affected the m RNA expression of Ephx1 and Ephx2(P< 0.05).However,temperature and exercise,as well as exercise and feeding only had significant interaction on Ephx1 m RNA expression(P< 0.01,P< 0.05).5)The protein expressions of Ephx1 and Ephx2 in NE group were significantly higher than those in NC group(P<0.05),and those in CC and CCR groups were significantly increased(P<0.01).Compared with NE,the expression of Ephx2 protein in CE and CEr groups was significantly increased(P<0.01,P<0.05).Compared with CC group,Ephx1 expression was significantly decreased in CE group(P< 0.01),and Ephx 2 expression was significantly increased(P<0.01).Three-factor analysis showed that Ephx1 was significantly affected by low temperature,exercise and feeding(P<0.01),and the protein expression of Ephx1 was significantly cross-affected by temperature and exercise,exercise and feeding(P< 0.05,P< 0.01).6)Compared with the NC group,the area under ITT curve(ITT-AUC)in the NE group was significantly decreased(P<0.05),and the HOMA-IR was significantly decreased;ITT-AUC and HOMA-IR in CC,CE,CCR and CER groups were significantly decreased(P<0.01);FINS in CE and CER groups were significantly lower than those in the corresponding control group(CE vs.CC,CER vs.CE,P <0.01).The results of three-factor variance showed that the influence of temperature and exercise on FINS and HOMA-IR was extremely significant(P<0.01),and the influence of food intake was significant(P < 0.05).7)Correlation analysis showed that 12,13-DiHOME was significantly negatively correlated with body weight(r=-0.8397,P< 0.01),Lee’s index(r=-0.8446,P< 0.01),visceral fat rate(r=-0.8134,P< 0.01),serum TG(r=-0.5618,P< 0.01),fasting BG(r=-0.4772,P< 0.01)and HOMA-IR(r=-0.7033,P< 0.01)after 5wk cold environment exercise intervention.There was a significant Positive correlation between Ephx1(r=-0.6557,P< 0.01)and Ephx 2(r=-0.7444,P< 0.01).Conclusions:1)Cold,exercise or cold exposure combined with caloric control can improve visceral fat rate and dyslipidemia in obese rats,and the improvement effect of cold exposure or combined with caloric control is better than that of single intervention,and this effect is synchronized with the up-regulation of CD36 and FATP1 gene and protein expression.2)Cold exposure promoted the synthesis of 12,13-DiHOME in brown adipose tissue by increasing Ephx1/2 expression,which was superior to exercise intervention.Exercise in cold promoted the transport of 12,13-DiHOME in brown adipose tissue to circulation and skeletal muscle.3)Exercise in cold or in combination with caloric control can improve insulin sensitivity,and is related to the secretion level of 12,13-DiHOME. |
PDF Full Text Request