The research roundup provides an overview of the past week’s research from Mayo Clinic Laboratories consultants, including featured abstracts and a complete list of published studies and reviews.
Direct free fatty acid (FFA) storage into adipocytes relates to body fat distribution. Adipose tissue CD36, acyl-CoA synthetase (ACS), and diacylglycerol acetyl-transferase (DGAT) may account for some of the between-depot and inter-individual variability in FFA storage. These studies were to test whether CD36, ACS or DGAT might be important for direct palmitate storage under meal-ingestion or high FFA conditions. We measured upper (UBSQ) and lower body subcutaneous (LBSQ) adipose tissue FFA storage rates by infusing palmitate tracers intravenously and performing adipose biopsies under hypoinsulinemic (high FFA) and mixed meal conditions. We recruited 5 postmenopausal women, physically active males (5) and females (5), and sedentary males (5) and females (5). We found: 1) the ratio of UBSQ to LBSQ DGAT activity predicted the ratio of palmitate storage (adjusted R = 0.25, F = 8.0, P = 0.01, 95% CI (0.07, 0.48)) under high FFA conditions; 2) the ratio of UBSQ to LBSQ ACS activity predicted the ratio of palmitate storage under meal conditions (adjusted R = 0.18, F = 6.3, P = 0.02, 95% CI (0.12, 1.28); 3) LBSQ direct palmitate storage rates were significantly less in physically active than sedentary adults; 3); 4) adipose tissue CD36 protein content, ACS or DGAT activities did not independently predict palmitate storage rates. We conclude that physically active adults have lesser fatty acid cycling back into adipose tissue and that adipose ACS and DGAT may affect competition between UBSQ and LBSQ adipose for direct palmitate storage. Via American Journal of Physicology. Endocrinology and Metabolism.