EFFECT OF OLEANOLIC ACID ON 5A-REDUCTASE ACTIVITY, DPCS PROLIFERATION AND GENE EXPRESSION CORRELATED WITH ANDROGENETIC ALOPECIA IN VITRO

Objective: Androgenetic alopecia (AGA) has a serious influence on the appearance and psychology of alopecia patients; how-ever, the current primary treatments have unwanted side effects and transient actions. New drugs for alopecia need to be developed. Oleanolic acid (OA), a natural pentacyclic triterpenoid, has several benefits and medicinal properties. Our previous in vitro study determined that OA showed the strongest effect of promoting hair growth among 55 Chinese herbal medicines; however, data are still scarce, making it difficult to discover the underlying mechanisms responsible for OA promoting hair growth, especially its anti-androgenic effects. This study aims to test the anti-androgenic effects of OA. Methods: Crude enzymes were isolated from SD rat prostate and liver to perform 5 alpha-reductase activity assays. The growth of human Dermal Papilla Cells (DPCs) was measured by the CCK-8 assay. Quantitative Real-Time PCR reactions were performed to determine gene expression changes of DPCs. Results: OA markedly decreased the 5 alpha-reductase activity in a dose-dependent manner. The cell proliferation of cultured DPCs was significantly promoted by OA. Multiple genes associated with the progression of AGA, including SRD5A1, SRD5A2, TGF-beta 1, TGF-beta 2, AR, ER, DKK-1, IGF-1 and VEGF, were found to be regulated by OA. Conclusion: OA could directly inhibit 5 alpha-reductase activity, promote DPC proliferation, change DPC gene expression and reduce the impact of DHT on DPC gene expression. OA may promote hair growth through the mechanisms above, and could have potential for use in future treatment against AGA.