Prostanoid receptors in anagen human hair follicles

Abstract

Prostanoid pathway in hair follicle gained closer attention since trichogenic side-effects on hair growth has been observed concomitantly with prostaglandin F 2a receptor (FP) agonist treatment of intraocular pressure. We thus investigated prostanoid receptor distribution in anagen hair follicle and different cell types from hair and skin. Using RT-PCR, Western blot and immunohistochemistry (IHC), we found that all receptors were present in hair follicle. This data shed new light on an underestimated complex network involved in hair growth control. Indeed most of these receptors showed a wide spectrum of expression in cultured cells and the whole hair follicle. Using IHC, we observed that expression of prostaglandin E 2 receptors (EP 2 , EP 3 , EP 4 ), prostaglandin D 2 receptor (DP 2 ), prostanoid thromboxane A 2 receptor (TP) and to a lesser extent EP 1 involved several hair follicle compartments. On the opposite, Prostaglandin I 2 receptor (IP) and DP 1 were more specifically expressed in hair cuticle layer and outer root sheath (ORS) basal layer, respectively. FP expression was essentially restricted to ORS companion layer and dermal papilla (DP). Although extracting a clear functional significance from this intricate network remains open challenge, FP labelling, i.e. could explain the biological effect of PGF 2a on hair regrowth, by directly modulating DP function.

Wnt5a attenuates Wnt/β‐catenin signalling in human dermal papilla cells

“…As strong expression of Wnt5a occurs in DP of human anagen hair follicles (22) and expression of Wnt3a occurs in both matrix cells as well as root sheath cells in anagen hair follicles ( Figure S1), in the perspective of hair biology, attenuation of Wnt3a-mediated signalling by Wnt5a in DP cells as an apparent autocrine manner strongly suggests that matrixderived Wnt3a activity is inhibited by Wnt5a from DP. For example, response to prostaglandin E2 (PGE2) may be modulated by DP-derived Wnt5a in response to Wnt3a from surrounding matrix cells because expression of EP2, a Wnt3a target (25), occurs in DP of anagen hair follicles (26). This speculation is in line with the finding of a study using whisker follicle organ culture, which demonstrated inhibited growth of the hair shaft by Wnt5a (21).…”

International Union of Basic and Clinical Pharmacology. LXXXIII: Classification of Prostanoid Receptors, Updating 15 Years of Progress

“…On the other hand, the psychological impact of male pattern baldness cannot be underestimated, and balding men are typically highly motivated and inclined toward subtle and natural intervention. FP receptor expression has been detected in the human dermal papillae (Colombe et al, 2008), which supports a favorable outcome for human clinical investigation. Fat reduction/antiobesity is a further potential pharmacocosmetic/medical use of FP agonists, but this is still at the adipocyte precursor stage essentially (Serrero and Lepak, 1997).…”

The Prostanoid EP4 Receptor and Its Signaling Pathway

“…UV-B exposure induced EP4 relocalization to the plasma membranes of keratinocytes, whereas its diffuse cytoplasmic staining pattern was unchanged in the rest of the epidermis. EP4 expression was also detected in sebocytes (Chen et al, 2009), hair follicles (Colombe et al, 2008), melanoma cells (Singh and Katiyar, 2011), and squamous cell carcinoma (Lee et al, 2005) in humans. Kabashima et al (2003) reported the expression of EP4 receptor transcripts in Langerhans cells prepared from epidermis.…”