[Protective effect of preconditioning with PEP-1-CAT fusion protein against myocardial ischemia-reperfusion injury in rats].
OBJECTIVE
To investigate the transduction efficiency of purified PEP-1-CAT fusion protein into rat heart and the protective effect of the fusion protein against myocardial ischemia-reperfusion injury.


METHODS
PEP-1-CAT or CAT (500 microg) was injected in SD rats via the caudal vein, using normal saline as the control, and the hearts were harvested at 0.5, 1, 2, 4, 8, and 24 h after the injection. The transduction efficiency was evaluated by immunofluorescence technique, and the CAT activity was measured. Forty rats were randomized into 5 groups, namely the sham-operated group, ischemia-reperfusion group, and 3 PEP-1-CAT -treated groups (100, 300, and 500 microg). The left main coronary artery was occluded for 1 h followed by a 2-h reperfusion, and at the end of reperfusion, serum LDH and CK and MDA content in the myocardium were measured.


RESULTS
No green fluorescence was observed in saline group or CAT group. Bright green fluorescence was observed in PEP-1-CAT groups at different time points, most conspicuous at 8 h. No significant difference in CAT activity was found between CAT group and saline group (P>0.05); with the lapse of time, CAT activity in PEP-1-CAT group increased gradually, reaching the peak level at 8 h, which was 4.2 folds of that in the saline group. LDH ,CK and MDA were significantly lower in PEP-1-CAT- groups than in ischemia-reperfusion group (P<0.01).


CONCLUSIONS
PEP-1 can mediate the transduction of CAT in rat heart in a time-dependent manner, and PEP-1-CAT preconditioning provides a protective effect against ischemia- reperfusion injury in rats.
Zhang
Yong-jun
YJ
Institute of Clinical Medicine, People's Hospital Affiliated to Yunyang Medical College, Shiyan 442000, China. ryzyj@163.com
Wang
Jia-ning
JN
Tang
Jun-ming
JM
Huang
Yong-zhang
YZ
Yang
Jian-ye
JY
Guo
Ling-yun
LY
D000818:Animals; D002374:Catalase / Q000378:metabolism / Q000494:pharmacology*; D003543:Cysteamine / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D019157:Ischemic Preconditioning, Myocardial; D008297:Male; D015428:Myocardial Reperfusion Injury / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D010455:Peptides / Q000378:metabolism / Q000494:pharmacology*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D011993:Recombinant Fusion Proteins / Q000494:pharmacology*; D014161:Transduction, Genetic
C503924:Pep-1 peptide; D010455:Peptides; D011993:Recombinant Fusion Proteins; D003543:Cysteamine; D002374:Catalase