Medullary differentiation-2 mediates obesity-induced myocardial injury by regulating adenosine AMPK
Objective To investigate the effects of medullary differentiation-2(MD-2)in obesity-induced myocardial injury by regulating adenosine 5'-monophosphate-activated protein kinase(AMPK)activity.Methods The obese mice model was established by feeding high-fat feed.The wild-type and MD-2 gene knockout mice were randomly divided into wild-type(WT)-control group(fed normally),WT-model group(fed with high-fat diet),knockout(KO)-control group(fed normally)and KO-model group(fed with high-fat diet)with 8 mice in each group.At week 16,creatine kinase-MB(CK-MB)and lactate dehydrogenase(LDH)were measured by reagent kits;the left ventricular ejection fraction(LVEF)and left ventricular fraction shortening(LVFS)were measured with ultrasonic apparatus;the pathological changes in myocardial tissue were observed by hematoxylin and eosin(HE)staining and Masson staining;the protein expression of phosphorylation AMPK(p-AMPK)was measured by Western blot.Results HE staining and Masson staining results revealed significant necrosis and fibrosis of the myocardial tissue in WT-model group,while the degrees of necrosis and fibrosis in KO-model group were significantly reduced.The LVEF values of the WT-control group,WT-model group,KO-control group and KO-model group were(83.98±7.58)%,(52.03±4.91)%,(76.42±3.89)%and(73.71±4.22)%,respectively;the LVFS values of each group were(53.61±8.51)%,(24.56±3.76)%,(48.14±5.00)%and(44.07±3.74)%,respectively;the CK-MB values of each group were(49.83±15.49),(83.75±11.90),(54.03±18.66)and(66.85±12.98)U·L-1,respectively;the LDH values of each group were(12.24±3.20),(27.90±6.10),(13.55±3.55)and(15.53±2.58)U·L-1,respectively;the relative expression levels of p-AMPK in each group were 221.31±88.76,46.29±10.07,148.66±32.02 and 161.49±78.11.Compared with WT-control group,the above indicators in WT-model group,compared with WT-model group,the above indicators in KO-model group,the differences were statistically significant(all P<0.05).Conclusion MD-2 mediates high-fat feed induced myocardial injury in obese mice by inhibiting AMPK activity.
medullary differentiation-2adenosine 5'-monophosphate-activated protein kinaseobesitymyocardial injury