E K Honoré1, J K Williams, M S Anthony, T B Clarkson. 1. Comparative Medicine Clinical Research Center, Bowman Gray School of Medicine of Wake Forest University, Winston-Salem, North Carolina.
Abstract
OBJECTIVE: To examine the effects of soy phytoestrogens on coronary vascular reactivity in atherosclerotic male and female rhesus monkeys. DESIGN: A prospective, randomized, blinded, controlled study. SETTING: Comparative Medicine Clinical Research Center of an academic medical center. PATIENT(S): Twenty-two young adult rhesus monkeys with pre-existing diet-induced atherosclerosis. INTERVENTION(S): Monkeys were fed soy-based diets for 6 months identical in composition, except that the isoflavones were extracted from one flow-isoflavone) and intact in the other (high-isoflavone). Quantitative coronary angiography was performed at the end of the study period. Females in the low-isoflavone group under went a second angiography after an acute IV dose of genistein. MAIN OUTCOME MEASURE(S): Percent change in diameter of the proximal left circumflex coronary artery in response to intracoronary acetylcholine and nitroglycerin, compared with control diameter. RESULT(S): Arteries from males constricted in response to acetylcholine. Arteries from females in the low-isoflavone group constricted (-6.2% +/- 2.8%, mean +/- SEM), whereas arteries from females in the high-isoflavone group dilated (6.4% +/- 1.2%, mean +/- SEM). Intravenous administration of genistein caused dilation in the previously constricting low-isoflavone females (3.3% +/- 2.8%). CONCLUSION(S): Like mammalian estrogens, dietary soy isoflavones enhance the dilator response to acetylcholine of atherosclerotic arteries in female monkeys.
OBJECTIVE: To examine the effects of soy phytoestrogens on coronary vascular reactivity in atherosclerotic male and female rhesus monkeys. DESIGN: A prospective, randomized, blinded, controlled study. SETTING: Comparative Medicine Clinical Research Center of an academic medical center. PATIENT(S): Twenty-two young adult rhesus monkeys with pre-existing diet-induced atherosclerosis. INTERVENTION(S): Monkeys were fed soy-based diets for 6 months identical in composition, except that the isoflavones were extracted from one flow-isoflavone) and intact in the other (high-isoflavone). Quantitative coronary angiography was performed at the end of the study period. Females in the low-isoflavone group under went a second angiography after an acute IV dose of genistein. MAIN OUTCOME MEASURE(S): Percent change in diameter of the proximal left circumflex coronary artery in response to intracoronary acetylcholine and nitroglycerin, compared with control diameter. RESULT(S): Arteries from males constricted in response to acetylcholine. Arteries from females in the low-isoflavone group constricted (-6.2% +/- 2.8%, mean +/- SEM), whereas arteries from females in the high-isoflavone group dilated (6.4% +/- 1.2%, mean +/- SEM). Intravenous administration of genistein caused dilation in the previously constricting low-isoflavone females (3.3% +/- 2.8%). CONCLUSION(S): Like mammalian estrogens, dietary soy isoflavones enhance the dilator response to acetylcholine of atherosclerotic arteries in female monkeys.
Authors: Susan E Appt; Haiying Chen; Amanda K Goode; Patricia B Hoyer; Thomas B Clarkson; Michael R Adams; Mark E Wilson; Adrian A Franke; Jay R Kaplan Journal: Menopause Date: 2010-07 Impact factor: 2.953