Baicalin, a flavonoid isolated from Scutellaria baicalensis, is known to have multiple biological functions. Recent studies have demonstrated that baicalin treatment increases alkaline phosphatase activity (ALP) and osteoprotegerin secretion by osteoblasts. Furthermore, baicalin induces the differentiation of cultured osteoblasts via the activation of the Wnt/β-catenin signaling pathway. In this study, we evaluated the hair growth-promoting effects of baicalin in human follicular dermal papilla (DP) cells. A reporter assay and Western blotting were used to assess the effect of baicalin on β-catenin signaling in DP cells. ALP activity and messenger RNA (mRNA) expression were examined by ALP staining and real-time polymerase chain reaction (PCR), respectively. Growth factor expression levels were also evaluated using real-time PCR. Finally, the effect of baicalin on hair growth in vivo was examined by topical application of baicalin on the shaved dorsal skin of C57BL/6 mice.

Studies have shown an association between oxidative stress and alopecia. Patients with alopecia generally exhibit lower levels of antioxidants in their scalp area as well as a higher lipid peroxidation index. Tocotrienols belong to the vitamin E family and are known to be potent antioxidants. Hence, a study was conducted to investigate the effect of tocotrienol supplementation on hair growth in volunteers suffering from hair loss. Twenty one volunteers were randomly assigned to orally receive 100 mg of mixed tocotrienols daily while 17 volunteers were assigned to receive placebo capsule orally. The volunteers were monitored for the number of hairs in a pre-determined scalp area as well as the weight of 20 strands of 1 cm length hair clippings at 0 (before supplementation), 4 and 8 months. The number of hairs of the volunteers in the tocotrienol supplementation group increased significantly as compared to the placebo group, with the former recording a 34.5% increase at the end of the 8-month supplementation as compared to a 0.1% decrease for the latter. Nevertheless, the cumulative weight of 20 strands of hair clippings did not differ much from the baseline for both supplementation groups at the end of the study period.

This study investigated the potential hair regrowth effects associated with a plant extract of Perilla frutescens, which was selected due to its putative hair regrowth activity. Extracts were prepared from dried P. frutescens suspended in distilled water, where the resultant aqueous suspension was fractionated sequentially using hexane, ethyl acetate, n-butanol, and distilled water. We observed that the n-butanol fraction resulted in the highest hair regrowth activity. The n-butanol soluble fraction of P. frutescens extract (BFPE) was further separated using AB-8 macroporous resin and silica gel chromatography to obtain rosmarinic acid (RA), which demonstrated effective hair growth regeneration potential. BFPE also showed in vivo anti-androgenic activity following the use of a hair growth assay in testosterone-sensitive male C57Bl/6NCrSlc mice. Furthermore, the effects of cell viability promotion were investigated following an in vitro analysis in primary hair follicle fibroblast cells (PHFCs) treated with RA. The results suggested that RA was the active compound in P. frutescens that triggers hair growth, and RA could be a potential therapeutic agent for the promotion of hair growth and prevention of androgenetic alopecia (AGA).