Intrinsic Factors Regulating Hair Growth: Insights Into Growth Factors, Cytokines, Chemokines, and Interferons

This review explores the intrinsic factors regulating hair growth, focusing on growth factors, cytokines, chemokines, and interferons. Key growth factors like HGF and VEGF promote hair growth through DNA synthesis and vascularization, respectively. Cytokines such as IL-1 and IL-6 inhibit hair growth, while IL-4, IL-12B, and IL-15 stimulate it by prolonging the anagen phase. Chemokines like CXCL12 inhibit growth by delaying the telogen-to-anagen transition, whereas CXCL1, CCL2, CCL5, and CCL9 promote growth through macrophage recruitment. Interferons IFN-beta and IFN-gamma inhibit growth by inducing the catagen phase. The review highlights the need for more human studies to validate these findings and develop personalized hair disorder treatments.