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Adipose biopsy techniques are relatively undefined for exercise physiology research in individuals at or near normal weight. The purpose of this study was to compare the influence of two adipose biopsy techniques on tissue quality through measurements of adipocyte cell size, as well as mRNA and protein levels of select pro- and anti-inflammatory cytokines and adipokines. Thirteen participants (9 M, 4 W; 28 ± 4 yr; 27 ± 3 kg·m-2; VO2max: 3.3 ± 0.7 L·min-1) underwent subcutaneous adipose biopsies on either side of the umbilicus (incision: ~8 cm lateral, sampling area: ~5 cm lateral) using 1) a 6-mm Bergström biopsy needle and 2) a mini-liposuction approach with a 4-mm Mercedes biopsy needle that used prebiopsy tumescent delivery (~30 mL 0.9% NaCl solution) into the sampling area (i.e., 'wet' technique). Tissue obtained was processed identically for analysis and both techniques returned high-quality tissue for histology (similar % intact adipocytes), mRNA (RNA integrity numbers >7.0), and protein. Adipocyte size was similar (P > 0.05) between both techniques (Bergström: 6,116 ± 1,652 µm², 554-23,522 lm2; Mercedes: 6,517 ± 952 µm², 926-21,969 lm²). There were also no differences (P > 0.05) between the two techniques for the measured cytokines (pro- and anti-inflammatory) and adipokines at the mRNA and protein levels. Adipocyte size was positively correlated with body mass index and body fat percentage, and negatively correlated with V O2max (P < 0.05). These results suggest both adipose biopsy techniques used in the current investigation are appropriate for histological, transcriptional, and translational level measurements in exercise physiology studies of nonobese women and men. [ABSTRACT FROM AUTHOR]

Prostaglandin (PG) E2 has been linked to increased inflammation and attenuated resistance exercise adaptations in skeletal muscle. Nonaspirin cyclooxygenase (COX) inhibitors have been shown to reduce these effects. This study examined the effect of low‐dose aspirin on skeletal muscle COX production of PGE2 at rest and following resistance exercise. Skeletal muscle (vastus lateralis) biopsies were taken from six individuals (4 M/2 W) before and 3.5 hr after a single bout of resistance exercise for ex vivo PGE2 production under control and low (10 μM)‐ or standard (100 μM)‐dose aspirin conditions. Sex‐specific effects of aspirin were also examined by combining the current findings with our previous similar ex vivo skeletal muscle investigations (n = 20, 10 M/10 W). Low‐dose aspirin inhibited skeletal muscle PGE2 production (p < 0.05). This inhibition was similar to standard‐dose aspirin (p > 0.05) and was not influenced by resistance exercise (p > 0.05) (overall effect: −18 ± 5%). Men and women had similar uninhibited skeletal muscle PGE2 production at rest (men: 1.97 ± 0.33, women: 1.96 ± 0.29 pg/mg wet weight/min; p > 0.05). However, skeletal muscle of men was 60% more sensitive to aspirin inhibition than women (p < 0.05). In summary, the current findings 1) confirm low‐dose aspirin inhibits the PGE2/COX pathway in human skeletal muscle, 2) show that resistance exercise does not alter aspirin inhibitory efficacy, and 3) suggest the skeletal muscle of men and women could respond differently to long‐term consumption of low‐dose aspirin, one of the most common chronically consumed drugs in the world. [ABSTRACT FROM AUTHOR]