Mouse Dermal Papilla Cells

Hordenine Promotes Cell Proliferation and Elevates the Activity of Dermal Papilla Cells

Hair follicles have a growth cycle that can be disrupted, leading to alopecia. Current treatments for alopecia are limited due to inefficiency or side effects. Hordenine, a natural compound with various health benefits, has not been studied for its effects on hair growth. Wang's team aims to investigate whether Hordenine can promote hair growth by enhancing dermal papilla cell (DPC) activity and activating the Wnt/β-catenin signaling pathway.

As shown in Fig. 1A, Hordenine at 200 μmol/L was safe for DPCs. Treatment with 12.5-100 μmol/L of Hordenine promoted DPC proliferation, especially 50 μmol/L. The clone formation assay showed that the number of colonies significantly increased by Hordenine (50 μmol/L) compared to controls (Fig. 1B). Immunofluorescence staining analysis indicated more Ki67-positive cells in Hordenine-treated groups than in the control group (Fig. 1C, D). These results demonstrated that Hordenine promoted the proliferation of DPCs. As ALP is an index of DPCs induction potential, they investigated the expression of ALP in DPCs. ALP mRNA and protein levels were upregulated in Hordenine-treated DPCs in a dose-dependent manner (Fig. 1E, F). The mRNA levels of Versican and Wnt3a, which are related to DPC function, were detected. Q-PCR results showed that Hordenine treatment increased the expression of both genes (Fig. 1E). Taken together, these results indicated that Hordenine increased DPC proliferation and DPC induction activity in a dose-dependent manner.

DPC-Exos Promoted the Proliferation and Migration of Fibroblasts in a Concentration-Dependent Manner

Hair follicle (HF) regeneration after skin injury remains a major clinical challenge. Dermal papilla cell-derived exosomes (DPC-Exos) have great potential to induce HF neogenesis. However, the role and mechanism of DPC-Exos in HF regeneration during wound healing are still unclear. In this study, the effect of DPC-Exos on fibroblasts in wound healing was explored for the first time.

Fibroblasts are key cells in dermal skin and crucial for wound healing. DPC-Exos have the ability to promote the proliferation and migration of hair follicle stem cells and hair matrix cells. To verify whether DPC-Exos can also act on fibroblasts, Shang et al. first verified the uptake of DPC-Exos by fibroblasts. The results showed that after co-incubating PKH-26-labeled DPC-Exos with fibroblasts for 24 h, the fibroblasts could be taken up and internalized DPC-Exos. They then treated the fibroblasts with different concentrations of DPC-Exos. As shown in Fig. 2C, the CCK-8 assay showed that DPC-Exos could significantly promote fibroblast proliferation in a concentration-dependent manner, and it was statistically significant at 20 µg/mL and 40 µg/mL, with the most rapid proliferation at 24 h. The same promoting effect was also confirmed by EdU staining (Fig. 2E). The scratch and transwell assays showed that DPC-Exos could improve fibroblast migration in a concentration-dependent manner, and it was statistically significant at 20 µg/mL and 40 µg/mL (Fig. 2A, B, D). These results suggest that DPC-Exos could promote the proliferation and migration of fibroblasts.