Transcriptional Profile of Aging in Healthy Human Skin. Homo sapiens

Gene expression changes were assessed from the non sun-exposed skin of the lower back of 98 healthy males aged 19-86. We show that contrary to previous thought, genome wide transcriptional activity does not display an exclusively linear correlation with ageing, but rather, in human skin, undergoes a period of significant transient change between 30 and 45 years of age. The identified transient transcriptional changes suggest a period of heightened metabolic activity and cellular damage mediated primarily through the actions of TP53 (tumour protein 53) and TNF (tumour necrosis factor). We also identified a subgroup of the population characterised by increased expression of a large group of hair follicle genes that correlates strongly with a younger age of onset and increasing severity of androgenetic alopecia. Overall design: Skin was collected from the lower back at the level of the belt, aproximately 5cm lateral to midline from healthy males, (defined as; non-smoking, no hospital admissions in the previous 5 years, no significant medical conditions or medications). Each sample was individually hybridised to an exon 1.0 ST array.