Hair loss in Men

Pilot Study Finds Platelet-Rich Plasma (PRP) Reverses Male and Female Pattern Baldness

Growth factors in platelet-rich plasma (PRP) have been used to help soft tissue healing since the mid-1990’s. Recently, researchers have started to look at whether or not the growth factors in PRP might also help to reverse male– and female-pattern baldness (androgenetic alopecia).

Evidence that PRP may help to reverse this type of hair loss was found in a 2014 pilot study, “Platelet-rich plasma for androgenetic alopecia” published in Dermatologic Surgery. ((Schiavone G, Raskovic D, Greco J, Abeni D. Platelet-rich plasma for androgenetic alopecia: a pilot study. Dermatol Surg. 2014 Sep; 40(9):1010-9.)) In this study, researchers observed at least some noticeable improvement in 64 patients with androgenetic alopecia. Moreover, 47% of those patients experienced at least moderate to very good improvement, a level that the researchers defined as “clinically important.”

Platelet-Rich Plasma Possible Role in Hair Growth

Ongoing research has suggested various mechanisms by which PRP could reverse pattern baldness. For example, using human hair follicles in both cell cultures and in mice models, a 2011 study found that PRP was able to stimulate the proliferation of human dermopapillar cells, ((Takikawa M, Nakamura S, Nakamura S, Ishirara M, Kishimoto S, Sasaki K, Yanagibayashi S, Azuma R, Yamamoto N, Kiyosawa T. Enhanced effect of platelet-rich plasma containing a new carrier on hair growth.Dermatol Surg. 2011 Dec;37(12):1721-9.)) which in turn protected hair follicles cells from apoptosis, a process of programmed cell death. Additionally, this study suggested that PRP may be able to stimulate hair growth by prolonging the anagen (growth) phase of the hair cycle. More recently, a 2012 study found that PRP treatment significantly increased hair diameter. ((Li ZJ, Choi HI, Choi DK, Sohn KC, et al. Autologous platelet-rich plasma: a potential therapeutic tool for promoting hair growth. Dermatol Surg 2012;38:1040–6.))

Platelet-Rich Plasma for Androgenetic Alopecia: a Pilot Study

In order to better verify whether PRP could be a useful treatment for androgenetic alopecia, researchers used two treatments of PRP separated over a period of 3 months. Three months after the second treatment there was at least some improvement in almost all the patients due to an increase in hair thickness and/or more hairs, and 47% of the patients had at least moderate to very-good improvement. Patients with the most severe hair loss saw the greatest amount of improvement. Interestingly, both men and women in all age groups responded equally well to treatment.

Limitations of this Pilot Study

A limitation of the study was that each patient served as his or her own control. To more reliably test whether PRP therapy has clinical benefit for androgenetic alopecia, future studies will need to control for any spontaneous improvement by randomly assigning patients to separate treatment and control groups.

In addition, the data indicated that a retreatment with PRP at 10 to 12 months after an initial treatment may be advisable; however, a prolonged, more systematic observation on a larger number of patients would be needed to establish a reliable retreatment schedule.

In sum, this pilot study provides some preliminary evidence that PRP therapy may provide clinical advantage to patients with mild to moderate male or female pattern baldness.

Clinical Study: Platelet-Rich Plasma (PRP) Promotes Hair Growth in Men with Pattern Hair Loss

Growth factors in platelet-rich plasma (PRP) have been used to facilitate wound healing. Recently, studies have suggested that PRP may also serve as a safe and effective treatment option for male and female pattern hair loss, ((Schiavone G, Raskovic D, Greco J, Abeni D. Platelet-rich plasma for androgenetic alopecia: a pilot study. Dermatol Surg. 2014 Sep; 40(9):1010-9.))^, ((A. Trink, E. Sorbellini, P. Bezzola et al., “A randomized, double-blind, placebo- and active-controlled, half-head study to evaluate the effects of platelet-rich plasma on alopecia areata,” British Journal of Dermatology, vol. 169, no. 3,pp. 690–694, 2013.)) but those studies lack scientific controls.

To address these limitations, researchers conducted a controlled clinical study that was recently published in the journal BioMed Research International. The researchers found that treatment with platelet-rich plasma stimulated hair growth in 10 males with pattern hair loss (androgenetic alopecia). ((V. Cervelli, S. Garcovich, A. Bielli, G. Cervelli, B. C. Curcio, M. G. Scioli, A. Orlandi, P. Gentile. “The effect of autologous activated platelet rich plasma (AA-PRP) injection on pattern hair loss: clinical and histomorphometric evaluation,” BioMed Research International Volume 2014.))

Study: The Effect of Autologous Activated Platelet Rich Plasma Treatments on Pattern Hair Loss

In a bilateral controlled clinical study of 10 male patients with patterned hair loss, researchers treated half of a subject’s scalp with PRP and the other half with a placebo. Each patient received three PRP treatments at one-month intervals.

The researchers evaluated the benefit of PRP treatments by comparing the treated half of a scalp to its non-treated (control) half using three measures of hair growth: mean hair count, total hair density, and terminal (healthy) hair density.

Results

Compared to the non-treated portion of the scalp, the researchers found an increase in hair density of 27.7 hairs/cm² while in the non-treated portions the mean total hair density decreased by 2.0 hairs/cm². They also found significant increases in terminal hairs compared to the control side.

A Possible Mechanism of PRP-Driven Hair Growth

Past research has suggested that the presence of keratinocytes in the outer root sheath and in the dermal papilla causes growth in new blood vessels (angiogenesis) during anagen, ((L. Mecklenburg, D. J. Tobin, S.M¨uller-R¨over et al., “Active hair growth (anagen) is associated with angiogenesis,” Journal of Investigative Dermatology, vol. 114, no. 5, pp. 909–916, 2000.)) the growth phase of the hair follicle. Research suggests that these new blood vessels play an important role in hair growth.

This new study suggests that PRP may stimulate hair growth by causing an increase of keratinocytes in the epidermis and in the follicular bulge cells, along with an increase of small blood vessels around the hair follicles in the treated area.