Effect of tumour necrosis factor-alpha on total myofibrillar and sarcoplasmic protein synthesis and polysomal aggregation in rat skeletal muscles.
The total sarcoplasmic and myofibrillar protein synthesis was reduced in incubated fast-twitch extensor digitorum longus (EDL) and slow-twitch soleus of rat after in vivo tumour necrosis factor-alpha treatment at 50 micrograms/kg/day for 5 days. The rate of protein synthesis in the myofibrillar fraction was inhibited more severely (41% in EDL and 34% in soleus) than that in the sarcoplasmic fraction (23% in EDL and 14% in soleus). Sucrose density gradient centrifugation analysis indicated that TNF-alpha treatment impaired polysomal aggregation in rat diaphragm muscle. Compared with the control muscles, the ratio of 40S and 60S subunits to polysomes was higher in TNF-alpha treated muscles. These findings suggest a role for TNF-alpha in the translational regulation of protein synthesis in rat skeletal muscle.
Cheema
I R
IR
Division of Science and Mathematics, Bethune-Cookman College, Daytona Beach, Florida 32114, USA.
Hermann
C
C
Postell
S
S
Holifield
B
B
D000818:Animals; D003593:Cytoplasm / Q000187:drug effects; D008297:Male; D018656:Muscle Fibers, Fast-Twitch / Q000187:drug effects*; D009124:Muscle Proteins / Q000096:biosynthesis*; D018482:Muscle, Skeletal / Q000187:drug effects*; D009210:Myofibrils / Q000187:drug effects; D011132:Polyribosomes / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
D009124:Muscle Proteins; D014409:Tumor Necrosis Factor-alpha