Exploring Senolytic and Senomorphic Properties of Medicinal Plants for Anti-Aging Therapies

Senolytic and senomorphic therapies have gained more and more attention in the last decade. This kind of therapy is based on the killing of cellular senescent cells without harming the "normal" cells. Aging is not a disease. Clinical studies on healthy people will be difficult to conduct. Therefore, one possibility is to draw on the large repertoire of medicinal plants and use their senolytic properties to provide mild anti-aging therapies. Chamomile, goldenrod, <i>reishi</i>, and green tea were tested for their ability to trigger senolysis. Quercetin was used as control substance. Cellular senescence was induced with 25 µM etoposide in human dermal fibroblasts and established for at least 14 days. The plant extracts were tested for their antioxidant potential (DPPH assay) and their polyphenol content. Senolysis was determined by presto blue assay of young and etoposide-induced senescent cells, and SA-β-Gal assays were also performed. The senomorphic properties of the plants were investigated using IL-6 ELISA and qPCR. It turned out that chamomile triggers a kind of cytokine storm and causes the cytokine values in the ELISA and in the qPCR to rise extremely, and other senescence-associated phenotype (SASP) markers were also elevated. Goldenrod and quercetin tend to have a senolytic and senomorphic effect, respectively. Regarding the senolytic and senomorphic properties of herbs, we found that all tested herbs can have a senolytic effect, and a senomorphic effect of quercetin has also been discovered. With regard to the effect of chamomile, however, we can say that seemingly harmless tea products may have harmful effects, especially in combination with chemotherapy, at least in cell culture experiments. Nevertheless, inflammation is a double-bladed mechanism with positive effects, for example, in healing, but also known negative effects.