Effects of Baicalin on Alopecia and the Associated Mechanism

The aim of the present study was to explore the potential pharmacological mechanism of baicalin by combining network pharmacology prediction and the experimental verification of alopecia. Networks of baicalin-associated targets and alopecia-related genes were constructed using the STRING database. Potential targets and pathways associated with the therapeutic efficacy of baicalin were identified via enrichment analysis using Cytoscape and the database for annotation, visualization and integrated discovery (Metascape). The back hair of C57BL/6J mice was removed with depilatory cream to verify the therapeutic effect of baicalin. Human hair dermal papilla cells (HHDPCs) were used to explore the mechanism of action of baicalin. Network pharmacology analysis revealed that the potential targets of baicalin mainly include protein serine/threonine kinase, Src protein, epidermal growth factor receptor, and insulin-like growth factor 1 (IGF1), which were indicated to mediate neutrophil degranulation and regulation of cell-cell adhesion, vesicle lumen, cytoplasmic vesicle, membrane raft, and endopeptidase activity. Multiple pathways were identified, such as proteoglycans in cancer, PI3K/AKT, and forkhead box O signaling pathways. Following baicalin treatment for the experimental mice, the coverage, length, and weight of the hair increased in a baicalin dose-dependent manner. Moreover, the histological evaluation showed that the number of hair follicles increased after baicalin treatment and melanin formation were pronounced. In addition, baicalin induced an increase in the phosphorylated p-AKT, p-glycogen synthase kinase-3β, p-PI3K, TGF-β1, and vascular endothelial growth factor levels. Furthermore, the activation levels of key protein p-AKT were increased. Baicalin induced the proliferation of HHDPCs in vitro and significantly upregulated p-AKT, IGF1, and alkaline phosphatase. In conclusion, the present study revealed that the pharmacological mechanisms of baicalin in alopecia therapy were associated with the proliferation of DPCs, the activation of the AKT pathway, and the transmission of downstream signals, indicating that baicalin is a potential drug candidate for the clinical treatment of hair loss.