In this study, we describe the effects of Lactobacillus paracasei HY7015 (HY7015) on promoting mouse hair growth. Since our purpose was to increase hair growth through oral administration, medicinal yeast, at a suitable concentration for application in mice, was used as a positive control. First, experiments were conducted to determine the effect of HY7015 on proliferation of hair follicle dermal papilla cells (HFDPC), which are important contributors to hair growth. HY7015 stimulated HFDPC proliferation in vitro and increased their secretion of vascular endothelial growth factor and insulin-like growth factor-1. In mouse experiments, oral administration of HY7015 promoted hair growth and hair follicle maturation in the dorsal skin, as well as increasing growth factor levels in mouse serum. In summary, we demonstrate that L. paracasei HY7015 consumption can promote hair growth by stimulating HFDPC proliferation and growth factor secretion. Follow-up studies are warranted to determine the underlying mechanism, using various approaches, including investigation of changes in intestinal microbiota and alteration of gene and protein expression.
Keywords: IGF-1; VEGF; growth factor; hair loss.