Change of short-chain acyl-CoA dehydrogenase in heart failure after myocardial infarction in rats and the intervention of aerobic exercise / 中华危重病急救医学

ABSTRACT

Objective? To?Study?the?changes?of?short-chain?acyl-CoA?dehydrogenase?(SCAD)?in?heart?failure?(HF)?after?myocardial?infarction?(MI),?and?the?effect?of?aerobic?exercise?on?SCAD.? Methods? Healthy?male?Sprague-Dawley?(SD)?rats?were?divided?into?sham?operation?group?(Sham?group),?sham?operation?swimming?group?(Sham+swim?group),?HF?model?group?(LAD?group)?and?HF?swimming?group?(LAD+swim?group)?by?random?number?table?method,?with?9?rats?in?each?group.?The?left?anterior?descending?branch?of?coronary?artery?(LAD)?was?ligated?to?establish?a?rat?model?of?HF?after?MI.?In?Sham?group,?only?one?loose?knot?was?threaded?under?the?left?coronary?artery,?and?the?rest?operations?were?the?same?as?those?in?LAD?group.?Rats?in?Sham+swim?group?and?LAD+swim?group?were?given?swimming?test?for?1?week?after?operation?(from?15?minutes?on?the?1st?day?to?60?minutes?on?the?5th?day).?Then?they?were?given?swimming?endurance?training?(from?the?2nd?week?onwards,?60?minutes?daily,?6?times?weekly,?10?weeks?in?a?row).?Tail?artery?systolic?pressure??(SBP)?was?measured?before?swimming?endurance?training?and?every?2?weeks?until?the?end?of?the?10th?week.?Ten?weeks?after?swimming?training,?echocardiography?was?performed?to?measure?cardiac?output?(CO),?stroke?volume?(SV),?left?ventricular?ejection?fraction?(LVEF),?shortening?fraction?(FS),?left?ventricular?end-systolic?diameter?(LVESD),?left?ventricular?end-diastolic?diameter?(LVEDD),?left?ventricular?end-systolic?volume?(LVESV),?and?left?ventricular?end-diastolic??volume?(LVEDV).?Morphological?changes?of?heart?were?observed?by?Masson?staining.?Apoptosis?of?myocardial?cells?was?detected?by?transferase-mediated?deoxyuridine?triphosphate-biotin?nick?end?labeling?stain?(TUNEL)?and?apoptosis?index?(AI)?was?calculated.?Reverse?transcription-polymerase?chain?reaction?(RT-PCR)?and?Western?Blot?were?used?to?detect?the?mRNA?and?protein?expression?of?myocardial?SCAD?respectively.?In?addition,?the?enzyme?activity?of?SCAD,?the?content?of?adenosine?triphosphate?(ATP)?and?free?fatty?acid?(FFA)?in?serum?and?myocardium?were?detected?according?to?the?kit?instruction?steps.? Results? Compared?with?Sham?group,?Sham+swim?group?showed?SBP?did?not?change?significantly,?with?obvious?eccentric?hypertrophy?and?increased?myocardial?contractility,?and?LAD?group?showed?persistent?hypotension,?obvious?MI,?thinning?of?left?ventricle,?and?decreased?myocardial?systolic/diastolic?function.?Compared?with?LAD?group,?SBP,?systolic/diastolic?function?and?MI?in?LAD+swim?group?were?significantly?improved?[SBP?(mmHg,?1?mmHg?=?0.133?kPa)?119.5±4.4?vs.?113.2±4.5?at?4?weeks,?120.3±4.0?vs.?106.5±3.7?at??6?weeks,?117.4±1.3?vs.?111.0±2.3?at?8?weeks,?126.1±1.6?vs.?119.4±1.9?at?10?weeks;?CO?(mL/min)?59.10±6.31?vs.?33.19±4.76,?SV?(μL)?139.42±17.32?vs.?84.02±14.26,?LVEF?0.523±0.039?vs.?0.309±0.011,?FS?(28.17±2.57)%?vs.?(15.93±3.64)%,?LVEDD?(mm)?8.80±0.19?vs.?9.35±0.30,?LVESD?(mm)?5.90±0.77?vs.?7.97±0.60,?LVEDV?(μL)?426.57±20.84?vs.?476.24±25.18,?LVESV?(μL)?209.50±25.18?vs.?318.60±16.10;?AI?(20.4±1.4)%?vs.?(31.2±4.6)%;?all?P?<?0.05].?Compared?with?Sham?group,?the?mRNA?and?protein?expression?of?myocardium?SCAD,?the?activity?of?SCAD?in?Sham+swim?group?were?significantly?increased,?the?content?of?ATP?was?slightly?increased,?the?content?of?serum?FFA?was?significantly?decreased,?and?the?content?of?myocardial?FFA?was?slightly?decreased;?conversely,?the?mRNA?and?protein?expression?of?myocardium?SCAD,?the?activity?of?SCAD?and?the?content?of?ATP?in?LAD?group?were?significantly?decreased,?the?content?of?serum?and?myocardial?FFA?were?significantly?increased.?Compared?with?LAD?group,?the?mRNA?and?protein?expression?of?myocardium?SCAD,?the?content?of?ATP?were?significantly?increased?in?LAD+swim?group?[SCAD?mRNA?(2-&Delta;&Delta;Ct)?0.52±0.16?vs.?0.15±0.01,?SCAD/GAPDH?(fold?increase?from?Sham?group)?0.94±0.08?vs.?0.60±0.11,?ATP?content?(μmol/g)?52.8±10.1?vs.?14.7±6.1,?all?P?<?0.05],?the?content?of?serum?and?myocardial?FFA?were?significantly?decreased?[serum?FFA?(nmol/L)?0.11±0.03?vs.?0.29±0.04,?myocardial?FFA?(nmol/g)?32.7±8.2?vs.?59.7±10.7,?both?P?<?0.05],?and?the?activity?of?SCAD?was?slightly?increased?(kU/g?12.3±4.3?vs.?8.9±5.8,?P?>?0.05).? Conclusion? The?expression?of?SCAD?in?HF?was?significantly?down-regulated,?and?the?expression?was?significantly?up-regulated?after?aerobic?exercise?intervention,?indicating?that?swimming?may?improve?the?severity?of?HF?by?up-regulating?the?expression?of?SCAD.