Two quite interesting findings are presented in this open access paper. Firstly, the pigmented areas of skin called age spots are in large part generated by the presence of senescent cells and their detrimental effects on mechanisms of skin pigmentation. Secondly, one the skin treatments that has for years been touted as rejuvenating by vendors in the more dubious, unscientific end of the medical community in fact destroys a fair number of senescent cells and therefore might actually be a legitimate rejuvenation therapy, albeit limited to the skin. This is certainly a novelty, but I suppose that the research community might find more such cases as the understanding of senescent cells in aging continues to grow in detail and sophistication. There will be a certain amount of up-ending of expectations on all sides as rejuvenation therapies and their associated research communities make progress in the years to come.

A caveat on this research is that the portion using human data involves results obtained from only a few individuals, while much of the mechanistic examination in cells and tissues largely uses senescence induced in non-physiological conditions. Based on other research, cells made senescent in various non-physiological ways can differ in state significantly from those that arise naturally in the body. They are more or less vulnerable to different senolytics, for example. Still, this work is intriguing, a good start, and plausible when taken as a whole. I wouldn't be overly surprised to find it validated when a more extensive study is undertaken. One possible approach to independent confirmation is for the groups working on human trials of senolytic drugs to start paying attention to the age spots of their patients. This could be accomplished without excessive additional cost: a photographic record of hands and forearms, for example.

Senescent fibroblasts drive ageing pigmentation: ​A potential therapeutic target for senile lentigo