Background: Type 2 diabetes (T2D) and heart failure (HF) are associated with high levels of skeletal muscle (SkM) oxidative stress (OS). Health benefits attributed to flavonoids have been ascribed to antioxidation. However, for flavonoids with similar antioxidant potential, end-biological effects vary widely suggesting other mechanistic venues for reducing OS. Decreases in OS may follow the modulation of key regulatory pathways including antioxidant levels (e.g. glutathione) and enzymes such as mitochondrial superoxide dismutase (SOD2) and catalase. Methods: We examined OS-related alterations in SkM in T2D/HF patients (as compared vs. healthy controls) and evaluated the effects of three-month treatment with (-)-epicatechin (Epi) rich cocoa
HF (heart failure) and T2D (Type 2 diabetes) associate with detrimental alterations in SkM (skeletal muscle) structure/function. We have demonstrated recently that (−)-ERC (epicatechin-rich cocoa) improves SkM mitochondrial structure [Taub, Ramirez-Sanchez, Ciaraldi, Perkins, Murphy, Naviaux, Hogan, Ceballos, Maisel, Henry et al. (2012) Clin. Trans. Sci. 5, 43–47]. We hypothesized that an improved mitochondrial structure may facilitate the reversal of detrimental alterations in sarcomeric microstructure. In a pilot study, five patients with HF and T2D consumed ERC for 3 months; treadmill testing [V̇O2max (maximum oxygen consumption)] and SkM biopsies were performed. Western blot analysis, immunohistochemistry and electron microscopy were used. We
ntroduction: We conducted an open-label study to examine the effects of the flavonoid (-)-epicatechin in seven ambulatory adult patients with Becker muscular dystrophy (BMD). Methods: Seven participants received (-)-epicatechin 50 mg twice per day for 8 weeks. Pre- and postprocedures included biceps brachii biopsy to assess muscle structure and growth-relevant endpoints by western blotting, mitochondria volume measurement, and cristae abundance by electron microscopy, graded exercise testing, and muscle strength and function tests. Results: Western blotting showed significantly increased levels of enzymes modulating cellular bioenergetics (liver kinase B1 and 5′-adenosine monophosphate-activated protein kinase). Peroxisome proliferator-activated receptor gamma coactivator-1alpha, a transcriptional coactivator of genes involved
During exercise, skeletal muscle performance depends in great part on the use of aerobic metabolism to supply the energetic demand of contractions. Endurance training increases the muscle aerobic capacity, which is not only associated with enhanced exercise performance, but also with a decreased risk of cardiovascular and metabolic diseases. Recently, it has been shown that regular use of small doses of dark chocolate may result in similar health benefits to exercise training. We show here that mice fed for 15 days with (–)-epicatechin (present in dark chocolate) had improved exercise performance accompanied by: (1) an increased number of capillaries in