Intestinal Dysbiosis and Biotin Deprivation Induce Alopecia through Overgrowth of Lactobacillus murinus in Mice

In the 2017 study, researchers discovered that antibiotic-induced gut dysbiosis, specifically the overgrowth of Lactobacillus murinus, and dietary biotin deprivation led to alopecia in mice. The study involved groups of mice with sample sizes ranging from 4 to 5 per group. While biotin deprivation alone did not affect skin physiology, it did so when combined with vancomycin treatment, which increased L. murinus in the gut. This bacterium consumes biotin, leading to its depletion. Germ-free mice monocolonized with L. murinus and fed a biotin-deficient diet also developed alopecia, which was reversible with biotin supplementation. The findings indicate that gut microbiota alterations and biotin availability are linked to skin health and hair growth, with implications for understanding the relationship between gut health and skin diseases.