The Effect Of Different Exercise Styles Combined With MSTN Antibody On Insulin Resistance Rats And Its Molecular Mechanism

Objective:Insulin resistance has become a far-reaching impact of endocrine phenomenon,TypeⅡ diabetes and cardiovascular disease were triggered by insulin resistance which is a worldwide problem and has a serious impact on human activity.Therefore,how to prevent and improve insulin resistance has become a focus for basic research and clinical research.Movement is considered to be one of the effective ways to improve insulin resistance,but the relationship between movement types and effects for improving insulin resistance have not been studied yet,and the molecular mechanisms of improved insulin resistance by the movement has no a detailed report.Exercise can suppress the expression of MSTN which is a negative regulator for skeletal muscle and promote skeletal muscle hypertrophy.It was studied that MSTN can also activate FoxO1 through suppressing the activity of Akt,which cause an effect on glucose metabolism and protein metabolism and lead to insulin resistance.However,an effect,which suppressed Akt to its other downstream signaling molecules,has not been reported.Therefore,this study will be regard MSTN as an target to improve insulin resistance,through sports(climbing-pole training and aerobic exercise)and MSTN antibodies interfere with insulin resistance rats induced high-fat diet,testing their physiology and biochemical indexes associated with insulin resistance and impact on downstream signaling molecules of MSTN/PI3K/Akt signaling pathways,and detecting the effects on insulin signaling pathway which has always been considered closely related to improving insulin resistance.thus the resulting contrast the molecular mechanisms differences to improve insulin resistance among climbing-pole training,aerobic exercise and MSTN antibodies and choose an optimum intervention factor.Method:In this experiment,SD male rats are regard as the research object,using anti-climbing pole resistance exercise,aerobic exercise,preparation of preliminary experiments MSTN polyclonal antibody,anti-climbing pole resistance movement joint MSTN MSTN antibodies and antibody combined aerobic exercise five ways to intervene high-fat diet-induced insulin resistance in rats observed differences in these five ways to improve the effects and molecular mechanisms of insulin resistance.And rat body weight,grip strength and abdominal fat changes,changes in blood glucose in rats by oral glucose tolerance test(OGTT)and insulin tolerance test(ITT)detection,H&E staining of rat femoral quadriceps from the morphological changes in muscle fiber cross-sectional area,Elisa and conventional serum test kit method and insulin resistance in rat adipocytes changes associated with bone injury factors and enzymes,immunohistochemistry,Western Blotting,and reverse transcription-PCR,respectively detect changes in various signaling molecules downstream signaling pathways and insulin signaling pathways MSTN/PI3K/Akt the nucleic acid level and protein level.Results:1.The results of aerobic exercise on improving insulin resistanceProlonged high-fat diet could induce symptoms of insulin resistance in normal rats,and we regarded it as a model for ways to improve insulin resistance.Compared with normal rats,high-fat diet could increase the body weight(P<0.01),Lee’s index(P<0.01)and abdominal fat in rats,there was no significant difference in grip strength and muscle weight and muscle fiber cross-sectional area.An significant increase presented to in the blood glucose level(P<0.01),the blood glucose were tested by OGTT and had a slow decrease after reaching the peak,and had a high level at 120min.It was indicated that glucose tolerance impaired,the ability of glucose uptake and metabolism decreased,resulting in increased blood glucose.ITT showed that blood glucose level were declined,indicated that had reduced sensitivity of cells to insulin,resulting in impaired insulin function and high blood glucose.Compared with the high fat diet group(HF),aerobic exercise could significantly reduce the weight of insulin resistance model rats(7.50%),Lee’s index(4.77%),and abdominal fat weight(42.94%),increase the height of insulin resistance model rats(2.23%)and skeletal muscle weight(18.70%)and skeletal muscle fiber cross-sectional area,and reduce the symptoms of insulin resistance and hyperglycemia in rats.There was an increase in the content of serum CK(82.73%),HDL-c(256.30%),and Adiponectin(48.18%),and reducing in the content of serum FFAs(13.10%),TG(46.25%),CHO(25.53%),Resistin,IL-6(4.71%),and TNF-a(35.04%).Aerobic exercise could decrease the level of MSTN(P<0.01),Act R II B,insulin(serum,P<0.01),GSK-3p and FoxO1,and increase the level of insulin receptor(P<0.01),PI3K(P<0.05),Akt(P<0.05),Glut4(P<0.05),mTOR in nucleic acid level and protein level in quadriceps.2.The results of climbing-pole training combined with MSTN antibodies on improving insulin resistanceCompared with the HF group,the climbing-pole training combined with MSTN antibodies could significantly reduce the weight of insulin resistance model rats(10.77%),Lee’s index(3.61%)and abdominal fat weight(15.54%),increase length of insulin resistance model rats(2.88%),grip strength(17.45%),skeletal muscle weight(18.70%)and skeletal muscle fiber cross-sectional area,reduce the symptoms of insulin resistance in rats.There was an increase in the content of serum CK(44.18%),HDL-c(236.13%),Leptin(15.69%),and Adiponectin(34.73%)levels,a reduction in the content of serum FFAs(34.21%),TG(49.01%),CHO(36.60%),LDL-c(27.08%),Resistin(28.62%),IL-6(10.58%),and TNF-a(27.29%).The climbing-pole training combined with MSTN antibodies could decrease the level of MSTN(P<0.05),ActRⅡ B(P<0.05),insulin(serum,P<0.01),GSK-3p(P<0.01)and FoxO1(P<0.05)in nucleic acid level and protein level in quadriceps,and significantly increase the level of PI3K(P<0.01),Akt(P<0.01),Glut4(P<0.01)and mTOR(P<0.01),and had no significant change in insulin receptor.3.The results of MSTN antibody,climbing-pole training and aerobic exercise combined with MSTN antibodies on improving insulin resistanceThe effect of MSTN antibody,climbing-pole training and aerobic exercise combined with MSTN antibodies was similar to climbing-pole training combined with MSTN antibodies on improving insulin resistance,but effect was not obvious.Conclusion:1.Aerobic exercise,MSTN antibody and aerobic exercise combined with MSTN antibodies all can improve insulin resistance,but the molecular mechanisms are different.Aerobic exercise improves insulin resistance in two ways:one way is by inhibiting MSTN/PI3K/Akt signaling pathway,the other way is by activating insulin signaling pathway.However,the mechanism of improving insulin resistance through MSTN antibodies and aerobic exercise combined with MSTN antibodies is only by inhibiting MSTN/PI3K/Akt signaling pathway.The best result for improving insulin resistance is aerobic exercise.2.The climbing-pole training,MSTN antibody and climbing-pole training combined with MSTN antibodies all can improve insulin resistance and molecular mechanism are the same,They are all improve insulin resistance which is only by inhibiting MSTN/PI3K/Akt signaling pathway.The best result for improving insulin resistance is climbing-pole training combined with MSTN antibodies.3.Having a simple comparison between aerobic exercise and climbing-pole training combined with MSTN antibodies for the change of insulin resistance related factors,the preliminary view is that climbing-pole training combined with MSTN antibodies can better improve and cure insulin resistance than aerobic exercise.4.The weight,Lees index and abdominal fat have a different degrees of decline,an increased cross-sectional area of muscle fiber and skeletal muscle weight in in these five way interventions rats,lowered blood sugar,and producing a significant impact on adipocytokines related to insulin resistance and enzyme associated with bone damage.And climbing-pole training combined with MSTN antibodies is the best results.