Effects of dietary phytoestrogen on global myocardial ischemia-reperfusion injury in isolated female rat hearts.
We investigated the effects of phytoestrogen on global myocardial ischemia-reperfusion injury in five groups of female rats. A high-phytoestrogen group (HPE) was ovariectomized (Ovx) and fed a diet containing soybean protein and a high-isoflavone soy extract. Another Ovx group of rats was fed the same diet as the HPE group but treated with the estrogen receptor blocker ICI-182,780 (HPE + ICI). A third group of Ovx rats was fed a diet containing soybean protein alone (low-phytoestrogen content; LPE). A fourth Ovx group was fed a diet free of phytoestrogen (Ovx). The fifth group of rats was sham ovariectomized (sham). Hearts from all rats were subjected to 30 min of global, hypothermic (4 degrees C), cardioplegic ischemia and 120 min of normothermic (37 degrees C) reperfusion with oxygenated Krebs-Henseleit buffer. Compared with either the sham or the HPE group, the Ovx and HPE + ICI groups had significantly decreased first derivative of left ventricular pressure (dP/dt), coronary flow rate (CFR), nitrite production and mitochondrial respiratory function and significantly increased Ca2+ accumulation and myocardial histological and ultrastructural injury. The CFR of the LPE group was significantly different from that of either Ovx or HPE + ICI group but the dP/dt, nitrite production, Ca2+ accumulation, and mitochondrial function were not. Our results indicate that diets containing phytoestrogen extract play a cardioprotective role in global myocardial ischemia-reperfusion in female rats.
Zhai
P
P
Division of Cardiology, Department of Medicine, Johns Hopkins Medical Center, Baltimore, Maryland 21224, USA.
Eurell
T E
TE
Cotthaus
R P
RP
Jeffery
E H
EH
Bahr
J M
JM
Gross
D R
DR
D000818:Animals; D001783:Blood Flow Velocity / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D003326:Coronary Circulation / Q000187:drug effects; D004032:Diet; D004958:Estradiol / Q000031:analogs & derivatives / Q000097:blood / Q000494:pharmacology; D004968:Estrogens, Non-Steroidal / Q000097:blood / Q000494:pharmacology*; D005260:Female; D000077267:Fulvestrant; D006321:Heart / Q000187:drug effects* / Q000503:physiopathology; D066298:In Vitro Techniques; D007529:Isoflavones / Q000097:blood / Q000494:pharmacology; D008929:Mitochondria, Heart / Q000378:metabolism; D015425:Myocardial Reperfusion; D009206:Myocardium / Q000378:metabolism* / Q000473:pathology; D009573:Nitrites / Q000378:metabolism; D010052:Ovariectomy; D048789:Phytoestrogens; D028321:Plant Preparations; D051381:Rats; D017207:Rats, Sprague-Dawley; D011960:Receptors, Estrogen / Q000037:antagonists & inhibitors; D015427:Reperfusion Injury / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D030262:Soybean Proteins / Q000494:pharmacology; D016277:Ventricular Function, Left / Q000187:drug effects
D004968:Estrogens, Non-Steroidal; D007529:Isoflavones; D009573:Nitrites; D048789:Phytoestrogens; D028321:Plant Preparations; D011960:Receptors, Estrogen; D030262:Soybean Proteins; D000077267:Fulvestrant; D004958:Estradiol; D002118:Calcium