Short-term replacement of starch with isomaltulose enhances both insulin-dependent and -independent glucose uptake in rat skeletal muscle

Effect of Quercetin Treatment on Mitochondrial Biogenesis and Exercise-Induced AMP-Activated Protein Kinase Activation in Rat Skeletal Muscle

The purpose of this study was to evaluate the effect of chronic quercetin treatment on mitochondrial biogenesis, endurance exercise performance and activation levels of AMP-activated protein kinase (AMPK) in rat skeletal muscle. Rats were assigned to a control or quercetin group and were fed for 7 days. Rats treated with quercetin showed no changes in the protein levels of citrate synthase or cytochrome C oxidase IV or those of sirtuin 1, peroxisome proliferator-activated receptor gamma coactivator-1α or phosphorylated AMPK. After endurance swimming exercise, quercetin-treated rats demonstrated no differences in blood and muscle lactate levels or glycogen utilization speed compared to control rats. These results indicate that quercetin treatment does not stimulate mitochondrial biogenesis in skeletal muscle and does not influence metabolism in a way that might enhance endurance exercise capacity. On the other hand, the AMPK phosphorylation level immediately after exercise was significantly lower in quercetin-treated muscles, suggesting that quercetin treatment might provide a disadvantage to muscle adaptation when administered with exercise training. The molecular results of this study indicate that quercetin treatment may not be advantageous for improving endurance exercise performance, at least after high-dose and short-term therapy.

Effect of fish oil supplementation combined with high-intensity interval training in newly diagnosed non-obese type 2 diabetes: a randomized controlled trial

The additive effect of high-intensity interval training to fish oil supplementation on newly diagnosed type 2 diabetes is unknown. 173 newly diagnosed type 2 diabetes patients were randomly assigned into the control group (received corn oil), fish oil group (eicosapentaenoic acid, EPA:docosahexaenoic acid, DHA = 3:2, total 2.0 g/day), and the fish oil + high-intensity interval training group. Three instructed high-intensity interval training sessions (Monday, Wednesday, and Friday; 10 × 60-s cycling bouts) were performed for 3 months. Glycaemic control was assayed by serum haemoglobin A1c, fast glucose, fast insulin, and adiponectin. Homeostatic model assessment of insulin resistance was utilized to determine the homeostasis of pancreatic function. Fat mass, triglycerides, total cholesterol, low-density lipoproteins, and high-density lipoproteins were measured to indicate cardiovascular risk. Within and between groups analysis were performed with linear mixed-effects modeling (95% CIs and p values). When compared with fish oil, fish oil + high-intensity interval training intervention has significant additive beneficial effects on haemoglobin A1c (p<0.01), fast glucose (p<0.001), homeostatic model assessment of insulin resistance (p<0.05), adiponectin (p<0.05), fat mass (p<0.01), and total cholesterol (p<0.01), but not on fast insulin level to newly diagnosed non-obese type 2 diabetes. High-intensity interval training has an additive effect on fish oil supplementation on glycaemic control, insulin resistance, cardiovascular risk, and fat mass, which indicates the potential necessity of combining high-intensity interval training with fish oil.