Changes in myocardial proteomics in late phase of limb ischemic preconditioning in rats / 中华麻醉学杂志

ABSTRACT

Objective To investigate the changes in myocardial proteomics in the late phase of limb ischemic preconditioning (LIP) in rats.Methods Twelve pathogen-free adult male Sprague-Dawley rats,aged 8-9 weeks,weighing 260-280 g,were randomly assigned into LIP group (n=6) and control group (group C,n=6) using a random number table.Limb ischemia was preceded by 3 cycles of 5-min ischemia which was induced by ligation of the root of the right hindlimb with a rubber band followed by 5-min reperfusion in group LIP.At 24 h after LIP,the tissues were obtained from the left ventricle,and the isobaric tags for relative and absolute quantification technique and liquid chromatography-mass spectrometry were applied to detect the differences in protein expression profiles between the two groups (the difference in expression between the two groups＞ 1.2 times and P＜0.05).The identified differentially expressed proteins were analyzed using the bioinformatics,and some were further verified by Western blot.Results A total of 55 proteins were identified to be differentially expressed,and among the 55 proteins,the expression of 35 proteins was up-regulated,and the expression of 20 proteins was down-regulated.Bioinformatics analysis showed that most of the 55 proteins were organelles,cell membrane or macromolecular compounds,were involved in the process such as metabolism,biological regulation,stress response and signal transduction,and showed functions such as the binding affinity to molecules,catalytic activity,anti-oxidant activity,and modulation of the activity of enzyme.The results verified by Western blot were consistent with those shown by using the isobaric tags for relative and absolute quantification analysis.Conclusion The late phase of LIP can induce changes in the expression of the 55 proteins involving regulation of energy metabolism,anti-oxidant action,regulation of gene expression,and protein folding and degradation in the myocardium,which may be the mechanism of myocardial protection in rats.