Prostaglandin E2 induces transcription of skeletal muscle mass regulators interleukin-6 and muscle RING finger-1 in humans.

Cyclooxygenase (COX) inhibiting drugs augment muscle mass and strength improvements during resistance exercise based treatment of sarcopenia in older individuals. Initial evidence suggests a potential mechanism of COX inhibitor blunted prostaglandin (PG) E2 stimulation of interleukin (IL)-6 and the ubiquitin ligase MuRF-1, reducing their inhibition on muscle growth. The purpose of this investigation was to determine if PGE2 stimulates IL-6 and MuRF-1 transcription in skeletal muscle. Muscle biopsies were obtained from 10 young individuals and incubated ex vivo with PGE2 or control and analyzed for IL-6 and MuRF-1 mRNA levels. PGE2 upregulated (P<0.05) expression of both IL-6 (195%) and MuRF-1 (51%). A significant relationship was found between IL-6 and MuRF-1 expression after incubation with PGE2 (r=0.77, P<0.05), suggesting regulation through a common pathway. PGE2 induces IL-6 and MuRF-1 transcription in human skeletal muscle, providing a mechanistic link between COX inhibiting drugs, PGE2, and the regulation of muscle mass.