Altered mitogen-activated protein kinase signal transduction in human skin fibroblasts during in vitro aging: differential expression of low-density lipoprotein receptor.

Autor: Bose, Chhanda, Bhuvaneswaran, Chidambaram, Udupa, Kodetthoor B.
Předmět:
Zdroj: Journals of Gerontology Series A: Biological Sciences & Medical Sciences; Feb2004, Vol. 59 Issue 2, p126-135, 10p, 7 Diagrams, 1 Chart, 6 Graphs
Abstrakt: The purpose of the study was to investigate the correlation of low-density lipoprotein receptor (LDLr) and mitogen-activated protein kinases (MAPK) in fibroblasts after serial passage in vitro. We used early-passage ( approximately 20 mean population division, MPD) and late-passage ( approximately 60 MPD) human skin fibroblasts to study the LDLr expression and MAPK at basal and after interleukin-1beta (IL-1beta) stimulation. We found a reduced LDLr expression in late-passage fibroblasts in comparison with early-passage fibroblasts, and late-passage fibroblasts showed a delayed induction of MAPK after IL-1beta stimulation, confirmed by the delay in translocation of MAPK from cytoplasmic to nuclear fraction. Using two specific inhibitors of MAPK, we could show a reduced LDLr expression in early-passage fibroblasts, indicating a direct relationship between MAPK signaling and LDLr expression. We conclude that one of the reasons for reduced LDLr gene expression in late passage fibroblast is related to MAPK signaling. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index