Neves 2014 J Nutr Biochem
|Neves FA, Cortez E, Bernardoa AF, Mattos ABM, Vieira AK, Malafaia TO, Thole AA, Rodrigues-Cunha ACS, Garcia-Souza EP, Sichieri R, Moura AS (2014) Heart energy metabolism impairment in Western-diet induced obese mice. J Nutr Biochem 25:50-57.|
Abstract: Nutritional transition has contributed to growing obesity, mainly by changing eating habits of the population. The mechanisms by which diet-induced obesity leads to cardiac injury are not completely understood, but it is known that obesity is associated to cardiac function impairment and energy metabolism, increasing morbidity and mortality. Therefore, our study aimed to investigate the mechanisms underlying cardiac metabolism impairment related to Western diet-induced obesity. After weaning, male Swiss mice were fed a Western diet for 16 weeks in order to induce obesity. After this period, the content of proteins involved in the heart energy metabolism GLUT1, cytosolic lysate and plasma membrane GLUT4, AMPK, pAMPK, IRβ, IRS-1, PGC-1α, CPT1 and UCP2 was evaluated. Also, the oxidative phosphorylation of myocardial fibers was measured by high-resolution respirometry. Mice subjected to Western diet group (WG) presented altered biometric parameters compared to control group, including higher body weight, increased myocardial lipid deposition and glucose intolerance, which demonstrate the obesogenic role of Western diet. WG presented increased CPT1 and UCP2 contents and decreased IRS-1, plasma membrane GLUT4 and PGC-1α contents. In addition, WG presented cardiac mitochondrial dysfunction and reduced biogenesis, demonstrating a lower capacity of carbohydrates and fatty acids oxidation and also decreased coupling between oxidative phosphorylation and ATP synthesis. Cardiac metabolism impairment related to Western diet-induced obesity is probably due to damaged myocardial oxidative capacity, reduced mitochondrial biogenesis and mitochondria uncoupling, which compromise the bioenergetic metabolism of heart.
• Keywords: Diet-induced obesity, Mitochondrial bioenergetics, Mitochondrial biogenesis, Mitochondrial impairment, Western diet
• O2k-Network Lab: BR Rio de Janeiro Moura AS
Labels: MiParea: Respiration, Exercise physiology;nutrition;life style Pathology: Obesity
Organism: Mouse Tissue;cell: Heart Preparation: Permeabilized tissue
Coupling state: LEAK, OXPHOS Pathway: N, NS, ROX HRR: Oxygraph-2k