Ip Wendy T K, McAlindon Andrew, Miller Sarah E, Bell James R, Curl Claire L, Huggins Catherine E, Mellor Kimberley M, Raaijmakers Antonia J A, Bienvenu Laura A, McLennan Peter L, Pepe Salvatore, Delbridge Lea M D
Cardiac Phenomics Laboratory, Department of Physiology, University of Melbourne, Parkville, Australia;
Graduate School of Medicine, Centre for Human Applied Physiology, University of Wollongong, Wollongong, Australia; and.
Am J Physiol Heart Circ Physiol. 2016 Sep 1;311(3):H768-80. doi: 10.1152/ajpheart.00690.2015. Epub 2016 Jul 15.
A definitive understanding of the role of dietary lipids in determining cardioprotection (or cardiodetriment) has been elusive. Randomized trial findings have been variable and sex specificity of dietary interventions has not been determined. In this investigation the sex-selective cardiac functional effects of three diets enriched by omega-3 or omega-6 polyunsaturated fatty acids (PUFA) or enriched to an equivalent extent in saturated fatty acid components were examined in rats after an 8-wk treatment period. In females the myocardial membrane omega-6:omega-3 PUFA ratio was twofold higher than males in the omega-6 diet replacement group. In diets specified to be high in omega-3 PUFA or in saturated fat, this sex difference was not apparent. Isolated cardiomyocyte and heart Langendorff perfusion experiments were performed, and molecular measures of cell viability were assessed. Under basal conditions the contractile performance of omega-6 fed female cardiomyocytes and hearts was reduced compared with males. Omega-6 fed females exhibited impaired systolic resilience after ischemic insult. This response was associated with increased postischemia necrotic cell damage evaluated by coronary lactate dehydrogenase during reperfusion in omega-6 fed females. Cardiac and myocyte functional parameters were not different between omega-3 and saturated fat dietary groups and within these groups there were no discernible sex differences. Our data provide evidence at both the cardiac and cardiomyocyte levels that dietary saturated fatty acid intake replacement with an omega-6 (but not omega-3) enriched diet has selective adverse cardiac effect in females. This finding has potential relevance in relation to women, cardiac risk, and dietary management.
对膳食脂质在确定心脏保护（或心脏损害）中所起作用的确切理解一直难以捉摸。随机试验的结果各不相同，且膳食干预的性别特异性尚未确定。在本研究中，在为期8周的治疗期后，研究了三种富含ω-3或ω-6多不饱和脂肪酸（PUFA）或饱和脂肪酸成分含量相当的饮食对大鼠心脏功能的性别选择性影响。在ω-6饮食替代组中，雌性心肌膜的ω-6:ω-3 PUFA比值比雄性高两倍。在指定富含ω-3 PUFA或饱和脂肪的饮食中，这种性别差异并不明显。进行了分离心肌细胞和心脏Langendorff灌注实验，并评估了细胞活力的分子指标。在基础条件下，与雄性相比，喂食ω-6的雌性心肌细胞和心脏的收缩性能降低。喂食ω-6的雌性在缺血损伤后表现出收缩弹性受损。这种反应与喂食ω-6的雌性在再灌注期间通过冠状动脉乳酸脱氢酶评估的缺血后坏死细胞损伤增加有关。ω-3和饱和脂肪饮食组之间以及这些组内的心脏和心肌细胞功能参数没有差异。我们的数据在心脏和心肌细胞水平上均提供了证据，即用富含ω-6（而非ω-3）的饮食替代膳食饱和脂肪酸摄入对雌性具有选择性不良心脏影响。这一发现与女性、心脏风险和饮食管理具有潜在相关性。
