title: Phorbol ester PMA stimulates protein synthesis and increases the levels of active elongation factors EF-1 alpha and EF-2 in ageing human fibroblasts.
abstract: Phorbol esters modulate gene expression, reorganize the cytoskeleton and stimulate bulk protein synthesis and the steps of initiation and elongation. We have observed that a phorbol ester PMA stimulates protein synthesis and increases the amounts of active elongation factors, EF-1 alpha and EF-2 in cultured human fibroblasts MRC-5 undergoing ageing. Although bulk protein synthesis slows down during ageing, the cellular response to the stimulatory effects of PMA is higher in senescent cells. Similarly, despite the age-related decline in the amounts of active EF-1 alpha and EF-2, senescent cells exhibit a higher response to PMA. The results indicate an age-dependent increase of cellular responsiveness to PMA and provide evidence about both the integrity of the translational apparatus and the effectiveness of the signal transduction pathways during cellular ageing. In comparison, the effects of PMA on SV40-transformed MRC-5V2 cells were minimal.
authors.affiliation: Department of Chemistry, Aarhus University, Denmark.
authors.forename: A
authors.initials: A
authors.lastname: Derventzi
authors.forename: S I
authors.initials: SI
authors.lastname: Rattan
authors.forename: B F
authors.initials: BF
authors.lastname: Clark
mesh_terms: D000375:Aging / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000378:metabolism*; D006801:Humans; D009994:Osmolar Concentration; D020648:Peptide Elongation Factor 1; D020652:Peptide Elongation Factor 2; D010445:Peptide Elongation Factors / Q000378:metabolism*; D014176:Protein Biosynthesis; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D020648:Peptide Elongation Factor 1; D020652:Peptide Elongation Factor 2; D010445:Peptide Elongation Factors; D013755:Tetradecanoylphorbol Acetate