[Auricularia auricular polysaccharide protects myocardium against ischemia/reperfusion injury].
OBJECTIVE
To determine whether auricularia auricular polysaccharide (AAP) protects heart against ischemia/reperfusion (1/ R) injury and its underlying mechanisms.


METHODS
Male Sprague-Dawley rats, pretreated with AAP (50, 100, 200 mg/(kg x d), gastric perfusion) for 4 weeks, were used for Langendorff isolated heart perfusion. The hearts were subjected to global ischemia for 30 min followed by 120 min of reperfusion and the left ventricular hemodynamic parameters were measured. Formazan, a product of 2, 3, 5-triphenyl-tetrazolium chloride (TTC), which is proportional to myocardial viability, was measured at 490 nm, and the level of lactate dehydrogenase (LDH) in the coronary effluent was measured to evaluate the cardiac injury. The cardiac malondialdehyde (MDA), a product of lipid peroxidation, and superoxide dismutase (SOD) activity were determined after myocardial I/R.


RESULTS
The pretreatment with AAP at 50, 100, 200/(kg d) for 4 weeks before I/R increased myocardial formazan content, reduced LDH release, improved the recovery of the left ventficular developed pressure, maximal rise rate of left ventricular pressure, and rate pressure product (left ventricular developed pressure multiplied by heart rate) attenuated the decrease of coronary flow during reperfusion. The cardiac protective effect of high dose AAP was more potent than that of compound radix salviae miltiorrhizae (CRSM, 4 ml/(kg x d), gastric perfusion for 4 weeks). Pretreatment with AAP (100 mg/(kg x d)) markedly inhibited the increase of MDA level and the decrease of SOD activity induced by I/R in myocardium.


CONCLUSIONS
The findings indicate that in the isolated rat heart, AAP protects myocardium against ischemia/reperfusion injury via enhancing the activity of SOD and reducing lipid peroxidation in heart.
Ye
Ting-mei
TM
Department of Biology, College of Chemistry and Life Sciences, Lishui University, China.
Qian
Ling-bo
LB
Cui
Jie
J
Wang
Hui-ping
HP
Ye
Zhi-guo
ZG
Xia
Qiang
Q
D000818:Animals; D001487:Basidiomycota / Q000737:chemistry*; D008297:Male; D017202:Myocardial Ischemia / Q000473:pathology / Q000503:physiopathology*; D015428:Myocardial Reperfusion Injury / Q000503:physiopathology / Q000517:prevention & control*; D018384:Oxidative Stress / Q000187:drug effects; D011134:Polysaccharides / Q000302:isolation & purification / Q000494:pharmacology*; D020011:Protective Agents / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013482:Superoxide Dismutase / Q000378:metabolism
D011134:Polysaccharides; D020011:Protective Agents; D013482:Superoxide Dismutase