p38(MAPK) in the senescence of human and murine fibroblasts.

Oncogenic and environmental stresses, such as reactive oxygen species, UV radiation etc, can induce premature cellular senescence without critical telomere shortening. The role of the Ras/Raf/ERK signal transduction cascade in this process has been previously established, but recent evidence also indicates a critical role of the p38 MAP kinases pathway. Oncogenic and environmental stresses impinge upon the p38(MAPK) pathway, suggesting a major role of this pathway in senescence induced by stresses.

Artefactual effects of oxygen on cell culture models of cellular senescence and stem cell biology.

In life sciences, modelling of the in vivo conditions using in vitro models is an important tool to generate knowledge. Although aerobic organisms including mammals depend on accurate oxygen tension, mimicking physiological conditions in cell culture experiments is not very common. Due to the need for simple technical and experimental design, the requirement for simulating the in vivo oxygen tension parameters has been neglected over long time.

Expression profiling of senescent-associated genes in human dermis from young and old donors. Proof-of-concept study.

It is often described that it is difficult to really discriminate the cause of intrinsic skin aging. The aim of this study was to compare the profiles of expression of senescence-associated genes in biopsies of dermis from young and old human donors. TGF-beta1 was up-regulated in the dermis of old donors as well as the TGF-beta1-regulated genes.