Leptin controls hair follicle cycling

Abstract

Leptin is a cytokine well known for its ability to control body weight and energy metabolism. Several lines of evidence have recently revealed that leptin also plays an important role in wound healing and immune modulation in skin. Sumikawa et al. Exp Dermatol 2014 evaluated the effect of leptin on hair follicle cycling using mutant and wild-type mice. They report that leptin is produced in dermal papilla cells in hair follicles and that leptin receptor-deficient db/db mice show an abnormality in hair follicle cycling. Moreover, leptin injection induced the transition into the growth stage of the hair cycle (anagen). On this basis, it now deserves exploration whether leptin-mediated signalling is a key stimulus for anagen induction and whether this may be targeted to manage human hair disorders with defect in the control of hair follicle cycling.

RBM28, a protein deficient in ANE syndrome, regulates hair follicle growth via miR‐203 and p63

“…The study of isolated hair follicle organ cultures allowed us to demonstrate the deleterious effect of RBM28 deficiency on hair growth and pigmentation. This does not rule out a contributory effect of endocrine abnormalities to the hair phenotype of patients with ANE syndrome, with alterations in the endocrine system being known to affect hair such as in the case of leptin controlling the hair follicle cycle . Despite the likelihood of alternative influences, this study clearly indicates a direct role for RBM28 in the regulation of hair follicle growth.…”

Constitutive activation of Stat3 in mouse epidermis is linked to hair deficiency and cytoskeletal network damage

“…During the anagen stage, keratinocyte stem cells in the bulge region proliferate and subsequently differentiate into several lineages of cells to form new HF (1). HF cycling and hair growth are regulated in a myriad of ways via cytokines, growth factors, receptors and transcription factors (1,2). Uncontrolled signalling pathways resulting in overexpression and underexpression of HF proteins can cause severe hair growth abnormalities including hair loss (3,4).…”

The Role of Adipocytes in Tissue Regeneration and Stem Cell Niches

“…Furthermore, intradermal transplantation of APs activates hair follicle growth, indicating that APs are a key component of the hair follicle stem cell niche. Mature intradermal adipocytes express the adipokine leptin and may also stimulate hair growth, as treatment of human hair follicle organ cultures with leptin can enhance hair shaft length (Yang et al 2015), and injection of leptin into mouse skin can induce activation of hair follicle stem cells and hair growth (Sumikawa et al 2014, Watabe et al 2014). Whether adipocytes signal directly to epithelial cells or act through the dermal papilla remains to be determined.…”