Department of Health, Kinesiology & Applied Physiology, Concordia University, 7141 Sherbrooke West, Montreal, QC, H4B 1R6, Canada.
Department of Kinesiology and Physical Education, McGill Research Centre for Physical Activity & Health, McGill University, 475 Pine Avenue West, Montreal, H2W 1S4, QC, Canada.
J Physiol Biochem. 2019 Feb;75(1):65-72. doi: 10.1007/s13105-018-0653-x. Epub 2018 Oct 25.
Low-carbohydrate diets are considered to be an effective approach to weight loss and have, subsequently, grown in popularity. Despite the apparent health benefits that these diets may provide for insulin resistance, hypertension, and dyslipidemia, their implications on cardiomyocyte oxidative capacity have yet to be investigated. To evaluate the adaptations induced by a 6-week low-carbohydrate, high-fat (LCHF) diet on mitochondrial respiration, two groups of male mice were investigated: Apolipoprotein E-deficient mice on a LCHF diet (L-DIET) and apolipoprotein E-deficient mice on a regular rodent diet (CON). Heart tissue was extracted and used for high-resolution respirometry (HRR), while immunoblotting was performed to quantify mitochondrial density and complexes. The results demonstrate increased expression of all five mitochondrial subunits in the L-DIET group compared to control condition. Furthermore, HRR revealed increased efficiency of substrate consumption, implying augmented oxidative capacity in the L-DIET group. These findings further support the notion that cardiomyocytes prefer lipids as a primary fuel source, by demonstrating that the shift in metabolism caused by a LCHF diet facilitates such an environment. This provides important information regarding the effects of a LCHF on cardiomyocytes, especially when considering free radical production and heart dysfunction.
低碳水化合物饮食被认为是一种有效的减肥方法，因此越来越受欢迎。尽管这些饮食可能对胰岛素抵抗、高血压和血脂异常有明显的健康益处，但它们对心肌细胞氧化能力的影响尚未得到研究。为了评估 6 周低碳水化合物、高脂肪（LCHF）饮食对线粒体呼吸的适应性，研究了两组雄性小鼠：载脂蛋白 E 缺陷型小鼠的 LCHF 饮食（L-DIET）和载脂蛋白 E 缺陷型小鼠的常规啮齿动物饮食（CON）。提取心脏组织用于高分辨率呼吸测定（HRR），同时进行免疫印迹以定量线粒体密度和复合物。结果表明，与对照条件相比，L-DIET 组所有五个线粒体亚基的表达均增加。此外，HRR 显示出底物消耗效率的提高，这意味着 L-DIET 组的氧化能力增强。这些发现进一步支持了这样一种观点，即心肌细胞更喜欢脂肪作为主要燃料来源，因为它表明 LCHF 饮食引起的代谢转变促进了这种环境。这为 LCHF 对心肌细胞的影响提供了重要信息，特别是在考虑自由基产生和心脏功能障碍时。
