Figure 3.

Effects of HFS diet and botanical supplementation on substrate utilization in vivo and ex vivo in skeletal muscle and adipose tissue. The respiratory exchange ratio (RER) (A) reflects a shift toward fatty acid oxidation with HFS diets that was not altered by botanical supplementation. Activity (B) and energy expenditure (C) were not altered by diet. Fatty acid oxidation (FAO) was measured ex vivo in skeletal muscle (D) in the presence and absence of pyruvate to assess the impact of diet on substrate switching and metabolic flexibility in skeletal muscle. Adipose tissue explants were exposed to adrenergic stimulation by isoproterenol (E) and lipolytic rates were measured. Isoproterenol-induced lipolysis was reduced in the HFS compared to that in the LF controls, and the blunted response was accentuated by PMI5011 supplementation. Adipose tissue explants were treated with isoproterenol + or – insulin (F) to determine insulin suppression of lipolytic rate. HFS-fed mice supplemented with PMI5011 showed enhanced insulin-mediated suppression of lipolysis. Statistical significance was set at p < 0.05, (n = 10 per group), variability is expressed as mean ± SD.