Effect of a cyclooxygenase-2 inhibitor on postexercise muscle protein synthesis in humans

• Published in: American journal of physiology: endocrinology and metabolism Vol. 298; no. 2; pp. E354 - E361
• Main Authors: Burd, Nicholas A, Dickinson, Jared M, LeMoine, Jennifer K, Carroll, Chad C, Sullivan, Bridget E, Haus, Jacob M, Jemiolo, Bozena, Trappe, Scott W, Hughes, Gordon M, Sanders, Charles E., Jr, Trappe, Todd A
• Format: Journal Article
• Language: English
• Published: United States American Physiological Society 01.02.2010
• Subjects: Celecoxib; Cyclooxygenase 1 - drug effects; Cyclooxygenase 1 - genetics; Cyclooxygenase 1 - metabolism; Cyclooxygenase 2 - drug effects; Cyclooxygenase 2 - genetics; Cyclooxygenase 2 - metabolism; Cyclooxygenase 2 Inhibitors - pharmacology; Double-Blind Method; Exercise; Exercise - physiology; Human subjects; Humans; Male; Muscle, Skeletal - drug effects; Muscle, Skeletal - enzymology; Musculoskeletal system; Protein Biosynthesis - drug effects; Protein Biosynthesis - physiology; Protein synthesis; Pyrazoles - pharmacology; Reference Values; Resistance Training; RNA, Messenger - analysis; Sulfonamides - pharmacology; Young Adult
• ISSN: 0193-1849; 1522-1555; 1522-1555
• DOI: 10.1152/ajpendo.00423.2009

Human Performance Laboratory, Ball State University, Muncie, Indiana Submitted 6 July 2009 ; accepted in final form 24 November 2009 Nonselective blockade of the cyclooxygenase (COX) enzymes in skeletal muscle eliminates the normal increase in muscle protein synthesis following resistance exercise. The current study tested the hypothesis that this COX-mediated increase in postexercise muscle protein synthesis is regulated specifically by the COX-2 isoform. Sixteen males (23 ± 1 yr) were randomly assigned to one of two groups that received three doses of either a selective COX-2 inhibitor (celecoxib; 200 mg/dose, 600 mg total) or a placebo in double-blind fashion during the 24 h following a single bout of knee extensor resistance exercise. At rest and 24 h postexercise, skeletal muscle protein fractional synthesis rate (FSR) was measured using a primed constant infusion of [ 2 H 5 ]phenylalanine coupled with muscle biopsies of the vastus lateralis, and measurements were made of mRNA and protein expression of COX-1 and COX-2. Mixed muscle protein FSR in response to exercise ( P < 0.05) was not suppressed by the COX-2 inhibitor (0.056 ± 0.004 to 0.108 ± 0.014%/h) compared with placebo (0.074 ± 0.004 to 0.091 ± 0.005%/h), nor was there any difference ( P > 0.05) between the placebo and COX-2 inhibitor postexercise when controlling for resting FSR. The COX-2 inhibitor did not influence COX-1 mRNA, COX-1 protein, or COX-2 protein levels, whereas it did increase ( P < 0.05) COX-2 mRNA (3.0 ± 0.9-fold) compared with placebo (1.3 ± 0.3-fold). It appears that the elimination of the postexercise muscle protein synthesis response by nonselective COX inhibitors is not solely due to COX-2 isoform blockade. Furthermore, the current data suggest that the COX-1 enzyme is likely the main isoform responsible for the COX-mediated increase in muscle protein synthesis following resistance exercise in humans. celecoxib; [ 2 H 5 ]phenylalanine; resistance exercise Address for reprint requests and other correspondence: T. Trappe, Human Performance Laboratory, Ball State University, Muncie, IN 47306 (e-mail: ttrappe{at}bsu.edu ).