Frontiers in Bioscience-Landmark (FBL) is published by IMR Press from Volume 26 Issue 5 (2021). Previous articles were published by another publisher on a subscription basis, and they are hosted by IMR Press on imrpress.com as a courtesy and upon agreement with Frontiers in Bioscience.
TNF-alpha and cortisone impair peptide chain initiation by altering the availability of initiation factor EIF-4E
The effect of chronic tumor necrosis factor-α (TNF-α) and cortisone treatment on the concentration of translational initiation factor eIF-4E in rat skeletal muscle was evaluated. Crude muscle extracts from control and experimental groups (TNF-α s.c. @ 50 µg/kg body wt each day for 5 days or cortisone s.c. @ 100 mg/kg body wt for 5 days) were used to purify eIF-4E by immunoprecipitation and polyacrylamide gel electrophoresis (PAGE) followed by Western blot analysis. Quantification of eIF-4E was done by densitometry. Both TNF-α and cortisone induced a marked decline in the concentration of eIF-4E in rat skeletal muscle. There was no difference in the ratio of phosphorylated to unphosphorylated eIF-4E after TNF-α treatment. These findings suggest that both TNF-α and cortisone inhibit peptide chain initiation in skeletal muscle cells by decreasing the expression of eIF-4E.