Increased abundance of cytoplasmic and nuclear caveolin 1 in human diploid fibroblasts in H2O2-induced premature senescence and interplay with p38αMAPK

Treatment of IMR-90 human diploid fibroblasts with a sublethal concentration of H2O2 induces premature senescence. We investigated the protein abundance, subcellular localization and involvement of caveolin 1 in premature senescence. Caveolin 1 is a scaffolding protein able to concentrate and organize signaling molecules within the caveolae membrane domains. We report the first evidence of increased nuclear and cytoplasmic localization of caveolin 1 during establishment of H2O2-induced premature senescence. Moreover, we demonstrate that phosphorylation of caveolin 1 during treatment with H2O2 is dependent on p38α mitogen-activated protein kinase.