Suppression of FGF5 and FGF18 Expression by Cholesterol-Modified siRNAs Promotes Hair Growth in Mice

A study conducted on 50 mice found that cholesterol-modified siRNAs can effectively suppress the expression of FGF5 and FGF18 genes, which are known to inhibit hair growth. The suppression of these genes resulted in a significant promotion of hair growth in the mice. The siRNAs were administered either through intradermal injections or topical application. The most potent siRNA was 567–25/27, and its suppressive effects lasted up to 72 hours post-injection. The FGF5 siRNA treatment reduced FGF5 mRNA levels by up to 91.08 ± 2.13% and prolonged the anagen phase of hair follicles by two days. Similarly, the FGF18 siRNA treatment significantly reduced FGF18 mRNA and protein levels, resulting in an earlier transition from the telogen to anagen phase for hair follicles, shortening this transition by 3 days. These findings suggest that cholesterol-modified siRNAs targeting FGF5 and FGF18 could potentially be used as a treatment for promoting hair growth and treating hair loss conditions such as alopecia.