A novel peptide 'T14' reflects age and photo-aging in human skin

T14 is a 14mer peptide derived from the C-terminus of acetylcholinesterase (AChE). Once cleaved, it is independently bioactive of the parent molecule and enhances calcium influx in different cell types, in a range of scenarios: it binds to an allosteric site selectively on the alpha-7 receptor, where it modulates calcium influx and is thus a potential trophic agent, as already reported in a range of normal developmental scenarios. However, if inappropriately activated, this erstwhile beneficial effect converts to a toxic one, resulting in pathologies as disparate as Alzheimer's and various metastatic cancers. Given that epidermal keratinocyte cells have the same ectodermal origin as brain cells, as well as expressing AChE and the alpha-7 receptor, we have explored whether T14 plays a comparable role. Here we report that the T14 immunoreactivity is detectable in human keratinocytes with levels inversely related to age: this decrease is even more apparent with chronic photo-exposure and thus accelerated skin aging. We conclude that T14, an agent promoting cell growth and renewal in other parts of the body, also operates in skin, Moreover, monitoring of keratinocyte T14 levels might offer further insights into the now well reported link between degenerative diseases and epidermal cell profile.

Automated summary

T14 is a bioactive peptide derived from acetylcholinesterase (AChE) that enhances calcium influx in various cell types. It selectively binds to the alpha-7 receptor and can have both beneficial and toxic effects, depending on its activation. In this study, we found that T14 is present in human keratinocytes and its levels decrease with age, especially with chronic exposure to sunlight. This suggests that T14, known to promote cell growth and renewal in other parts of the body, also plays a role in skin and could be linked to degenerative diseases and epidermal cell profile.