Lactiplantibacillus plantarum ZJUIDS51 improves androgenic alopecia via gut-skin axis.

Androgen dysregulation is the primary driver of androgenetic alopecia (AGA), the most prevalent form of hair loss. This study aimed to evaluate the efficacy of Lactiplantibacillus plantarum ZJUIDS51 (Z51) in alleviating AGA using a C57BL/6 mouse model and to explore the underlying mechanisms associated with the gut-skin axis. The model was induced via intraperitoneal injection of dihydrotestosterone (DHT). Z51 was administered orally via gavage, while topical minoxidil and PBS gavage were used in the control groups. Results showed that Z51 intervention significantly promoted hair regeneration. By day 23, compared to the MC group, Z51 treatment resulted in an approximately 87% increase in hair coverage area and an approximately 68% increase in hair shaft length (both p < 0.0001). These improvements were preceded by enhanced hair follicle cell proliferation observed on day 10. Mechanistically, microbiome and metabolomic analyses suggest that Z51 remodeled the gut microenvironment. It modulated the abundance of androgen- and inflammation-related bacterial strains, thereby enhancing steroid metabolism and replenishing specific plant-derived antioxidant metabolites. In summary, Z51 ameliorated AGA through the gut-skin axis and provided insights into future treatments of AGA and the development of functional probiotics.