An Overview of the Biology of Platelet-Rich Plasma and Microneedling as Potential Treatments for Alopecia Areata

Platelet-rich plasma and microneedling have been investigated recently as potential therapeutic options for the treatment of hair disorders. Evidence from laboratory studies indicates that these treatments enhance growth factor production that in turn facilitates hair follicle development and cycling. Several small studies and case reports have presented encouraging findings regarding the use of these treatments for alopecia areata. Future investigations will be needed to validate these therapeutic techniques for patients with alopecia areata and further refine which subtypes of the disease these methods are best indicated for.

Introduction

Effective treatments for alopecia areata (AA) that can significantly alter the disease course have been the subject of countless research endeavors over the last several decades. A subset of patients with AA respond insufficiently to the conventionally available treatments and consequently seek alternative therapeutic options (Alkhalifah et al., 2010b). Platelet-rich plasma (PRP) is an autologous blood preparation that has undergone a platelet concentrating procedure (Eppley et al., 2004, Li et al., 2012). This technique was initially introduced to the medical community as a potential hemostatic agent used in the surgical setting and also for chronic nonhealing wounds (Cieslik-Bielecka et al., 2012, DelRossi et al., 1990). Since then, this therapy gained traction in other fields including orthopedics, oral and maxillofacial surgery, and plastic surgery for its use in tissue repair as it has been proposed that platelets release growth factors needed in the wound healing process (Albanese et al., 2013).

Recently, new non-FDA-approved indications for this technology have been developed in the field of dermatology including skin rejuvenation, scar revision, wound healing (in particular for ulcers), and other conditions such as striae distensae (Kumaran, 2014). PRP has also been explored in the context of hair disorders and evaluated for the treatment of androgenetic alopecia, and to enhance graft survival in hair transplantation (Schiavone et al., 2014, Uebel et al., 2006). Microneedling is also hypothesized to enhance growth factors, while augmenting collagen and elastin production and creating microchannels that allow for transdermal delivery of drugs through the stratum corneum (Arora and Gupta, 2012). This technique has similarly been evaluated for the treatment of androgenetic alopecia with promising results and may have applications for the treatment of other hair disorders (Dhurat et al., 2013). The purpose of this review is to discuss the proposed mechanisms for PRP and microneedling while also examining the evidence supporting the use of each of these treatments for patients with AA.