Telomerase rescues the expression levels of keratinocyte growth factor and insulin-like growth factor-II in senescent human fibroblasts.
Changes in expression levels of various cytokines, growth factors, and related genes were examined by reverse transcriptase polymerase chain reaction in a normal human fibroblast cell strain, TIG-3, along with in vitro aging. The expression levels of KGF and IGF-II were decreased with proliferative aging but not by growth arrest of young cells. In telomere-elongated cells prepared by transfection with human telomerase reverse transcriptase cDNA, high expression levels of these two genes were maintained, suggesting a causal relation between telomere shortening and reduced expression of KGF and IGF-II. The expression level of HGF was high in both growing and growth-arrested young cells but low in both senescent and telomere-elongated cells. The expression levels of follistatin and HB-EGF were high in both young growing and telomere-elongated cells but low in both senescent and growth-arrested young cells, indicating a growth-dependent expression. Expression levels of FGF-1, FGF-2, VEGF, BMP-3, and amphiregulin did not change with proliferative aging, growth arrest of young cells, or telomere elongation and life-span extension.
Kanzaki
Yukari
Y
Department of Cellular and Molecular Biology, Graduate School of Biomedical Sciences, Hiroshima University, Kasumi 1-2-3, Hiroshima City, Hiroshima 734-8551, Japan.
Onoue
Fumikazu
F
Ishikawa
Fuyuki
F
Ide
Toshinori
T
D000375:Aging / Q000502:physiology*; D002460:Cell Line; D016207:Cytokines / Q000378:metabolism; D017931:DNA Primers; D051523:Fibroblast Growth Factor 7; D005346:Fibroblast Growth Factors / Q000235:genetics / Q000378:metabolism*; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D007335:Insulin-Like Growth Factor II / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D019098:Telomerase / Q000235:genetics / Q000378:metabolism*; D016615:Telomere / Q000378:metabolism
D016207:Cytokines; D017931:DNA Primers; C496453:FGF7 protein, human; D012333:RNA, Messenger; D051523:Fibroblast Growth Factor 7; D005346:Fibroblast Growth Factors; D007335:Insulin-Like Growth Factor II; D019098:Telomerase