自体富血小板血浆治疗雄激素性秃发的研究进展

雄激素性秃发是最常见的脱发类型,呈进行性发展,且影响美观。近年来,富血小板血浆(PRP)被广泛地应用于医学实践中,PRP可以促进毛发的再生及伤口的愈合,但PRP在实际临床应用中仍存在一些问题。该文对PRP的制备方法、作用机制和临床应用作一综述。     

An umbrella review of the use of platelet-rich plasma in the treatment of androgenetic alopecia

Objective

To evaluate the efficacy of platelet-rich plasma (PRP) in the treatment of androgenetic alopecia, as well as establish an effective treatment protocol and optimal PRP preparation procedure.

Methods

We searched the PubMed, Scopus, Embase, Cochrane, CNKI, and Wanfang databases from inception to October 29, 2021, using PROSPERO's International Prospective Register of Systematic Reviews (registration ID: CRD42022295921).

Results

The original literature search revealed 215 reviews; after duplication removal, 89 papers were eliminated, 95 were eliminated after reading the titles and abstracts, and eventually, 28 articles were included after reading the complete text.

Conclusions

PRP treatment for androgenetic alopecia is effective, and we recommend the following: (1) a PRP volume of at least 0.05 ml/cm², preferably 0.1 ml/cm²; (2) at least three consecutive treatments at an interval of 1 month; (3) intensive therapy is beneficial and can be provided from 3 to 6 months after continuous treatment; (4) objective indicators such as hair diameter, hair count; (5) long-term follow-up.     

富血小板血浆局部注射治疗雄激素性脱发的疗效及安全性系统评价

目的：对富血小板血浆局部注射治疗雄激素脱发的有效性及安全性进行评价。方法：计算机检索截至2020年5月的Pubmed、Embase、the Cochrane library、Web of science、中国知网（CNKI）、中国生物医学文献服务系统、万方数据库、维普中文科技期刊全文数据库中关于富血小板血浆治疗雄激素脱发的随机对照试验，经2名医生筛选纳入文献并进行文献评价，最后对纳入文献进行分析，采用Revman 5.3软件进行meta分析。结果：纳入10个文献，212例患者。meta分析显示：①富血小板血浆注射可增加毛发密度，与安慰剂组比较差异有显著性（WMD=29.39，95% CI=1.89～56.89，P=0.04）。②局部暂时疼痛是主要的不良事件，其它少见的不良事件包括：出血、瘀斑、水肿等，无严重不良反应发生。结论：富血小板血浆局部注射有利于改善毛发密度，未发现严重不良反应。     

头皮带状硬皮病伴雄激素性秃发和斑秃一例

患者女,25岁.因顶部脱发4年,双颞部及枕部斑片状脱发1年,额部及头皮红斑、发硬3个月来我科就诊.4年前患者顶部头发逐渐稀少并进行性加重,1年前突然出现双颞侧和枕部头皮的斑片状脱发,3月前额中部偏左侧出现条带状、凹陷性的红斑;无雷诺现象.患者既往体健,其父有雄激素性秃发,余家族成员无类似疾病史.系统体检无异常发现.     

Expression of sex-determining genes in the scalp of men with androgenetic alopecia

BACKGROUND: The regulation of the cutaneous steroidogenesis in patients with androgenetic alopecia remains largely unclear. OBJECTIVE: The purpose of this study was to quantify the expression of the sex-determining genes in different scalp areas. METHODS: Paired scalp specimens from frontal and occipital scalp areas of 10 patients were examined by real-time RT-PCR for mRNA expression and of 40 patients (mean age 34.9 years, range 22-58) by Western blotting for protein analysis. RESULTS: The SOX-9 mRNA was most abundant in the skin, while SF-1 mRNA was sparsely detected. The protein levels of DAX-1, SRY and WT-1 were significantly higher in the bald scalp (p=0.003, 0.004 and 0.03, respectively). Only the SRY expression showed a positive correlation with the baldness severity in Norwood-Hamilton classification (p=0.024). There was no association between patient's age and the protein levels. Immunostaining of SOX-9 was detected in the outer root sheath keratinocytes of hair follicles but not in the dermal papillae. CONCLUSION: Further study on a larger population, including normal subjects and female patients, is needed to confirm the pathogenic role of sex-determining genes in androgenetic alopecia.     

Quantitative study of the human hair follicle in normal scalp and androgenetic alopecia

We carried out a quantitative study of the matrix and dermal papilla of the human hair follicle of the scalp, both normal and in various degrees of androgenetic alopecia. A stereological study showed the measured parameters to decrease with increase in the degree of alopecia, particularly as regards the total volume of the matrix and its papilla. The ratio of the two volumes increased by 30%, indicating a much more marked decrease in size of the papilla than in the matrix size. The number of cell nuclei in the matrix and the papilla of alopecic scalp was found to be 30% and 50% smaller, respectively, than those of normal scalp. Finally, a morphometric study revealed enlarged nuclei in the matrix and papilla, as shown by their increased areas, perimeters, and maximal diameters.     

Efficacy of platelet-rich plasma in the treatment of androgenetic (male-patterned) alopecia: A pilot randomized controlled trial

Background: Platelet-rich plasma (PRP) has been proposed as an effective treatment for different diseases. Objective: The aim of this study is to evaluate the efficacy of PRP in the treatment of androgenetic alopecia (AGA). Material and methods: In this study, 19 men with AGA were recruited among whom 17 men completed the trial. At the beginning, 2 square-shaped areas of 2.5 × 2.5 centimeters, at least 3 cm apart from each other were selected on the scalp of each patient as case and control sites. Then, 1.5 ml of PRP was injected in the case site, while in the control site the same amount of normal saline was injected. These were injected in 2 sessions, 1 month apart. The terminal and vellus hairs were counted in each square at the beginning of the study, and then 1, 3, and 6 months after the first injection. Results: In the case squares, the mean number of terminal and vellus hairs was 87 and 43 at the beginning and 85 and 42, respectively, at the end of six months. Conclusions: Our study showed that the PRP was not effective in treating AGA of grade 4–6.     

Functional analysis of the stratum corneum of scalp skin: studies in patients with alopecia areata and androgenetic alopecia

Abstract Because of the presence of thick long hairs on the scalp, little information is available concerning the functional characteristics of the stratum corneum (SC) of scalp skin. We therefore conducted a functional study of the SC of lesional scalp skin of patients with alopecia areata and of patients with androgenetic alopecia. We compared the scalp with the cheek and the flexor surface of the forearm (volar forearm). The water barrier function of the scalp SC of both patient groups, in terms of transepidermal water loss (TEWL), was almost comparable to that of the volar forearm, and was far better than that of facial skin. However, hydration of the scalp skin surface, as evaluated by measurement of high-frequency conductance, was markedly higher than that of facial skin, and showed significantly higher values than the volar forearm. These characteristics seem to be dependent, at least to some extent, on the amount of sebum-derived skin surface lipids because these were abundant on the scalp skin. Moreover, removal of skin surface lipids led to a significant decrease in skin surface hydration. The superficial corneocytes, the size of which reflects the proliferative activity of the epidermis, were substantially smaller on the scalp than on the volar forearm but significantly larger than on the cheek. These findings suggest that the rate of turnover of the scalp epidermis is intermediate between that of the facial and volar forearm epidermis. We conclude that the SC of the scalp skin in humans is functionally distinct from that of the face and extremities. Received: 6 January 2000 / Revised: 11 August 2000 / Accepted: 25 September 2000     

Platelet rich plasma in androgenetic alopecia: A systematic review

In recent years, dozens of manufacturers and clinics have been promoting the use of platelet rich plasma (PRP) procedures for skin and hair regeneration. Well‐designed randomized controlled studies for these procedures are lacking. In this communication, we review the efficacy and safety of PRP procedures for androgenetic alopecia from multiple published peer‐reviewed studies. The conclusion of our analysis is that until the present moment there is not enough evidence for the use of PRP procedures in the treatment of androgenetic alopecia. We hope that this review will help practitioners and patients to make better‐informed treatment decisions.     

雄激素性秃发的发病机制

【摘要】 雄激素性秃发（AGA）是最常见的一种非瘢痕性脱发类型。研究提示,AGA的发病机制涉及遗传背景、性激素代谢异常与毛囊微型化、毛囊微环境炎症反应以及环境因素等多个方面,其中遗传易感性是造成AGA个体发病差异最重要的因素,性激素代谢异常和/或毛囊微环境炎症反应诱发的毛囊微型化则是AGA发病的最后环节。     

Validation of scalp coverage scoring methods for scalp hair loss in male pattern hair loss (androgenetic alopecia)

BACKGROUND: Global evaluation of hair loss in male subjects affected by androgenetic alopecia has been proposed as a means for monitoring changes over time, including placebo-controlled drug efficacy studies. Because of the potential impact of subjectivity (e.g. placebo effect) of clinical investigators, global photographs (GPs) have been introduced as a more objective record. Examination of paired before and after pictures and rating on a seven-point scale (from greatly decreased -3 to greatly increased +3) have been historically introduced by United States of America (US) experts. METHODS: Based on published GPs and original GPs obtained at our clinical research facility, we developed a training set in order to allow European Union (EU) observers to practice and compare with ratings by the US experts. RESULTS: After training with the seven-point scale, there was a positive correlation between three US and three EU ratings (n=52 paired images from 35 different subjects, r=0.795). The results of a test-retest evaluation was performed on 18 paired images from the initial image collection by the three EU experts. Correlation r=0.806 and identical scores in 78% of cases documents a reproducibility similar to the single one US expert published data (119 subjects, retest correlation 0.76 with 75% identical duplicate ratings). Seventeen subjects taken from a placebo-controlled trial had GPs at 6 and 12 months. The average difference between an efficacious drug treatment and the placebo were almost similar in the US (0.833) as in the EU (0.689) expert panels. We also trained the EU experts in performing the scalp coverage scoring (SCS), a novel system for the global evaluation of scalp hair in vivo and on GP. SCS was performed on single images (randomised as to time and treatment) taken from the same set of 17 paired GPs. This showed a between-group difference of 0.055 at 6 months and 0.201 at 12 months, i.e. 5% improved coverage in favour of the active group. CONCLUSION: After completion of our study, US and trained - calibrated EU experts seem equally valuable in comparing before-after GPs. SCS can also be used on GPs and may support the clinical investigator during inclusion of test subjects and for real-time efficacy evaluation during the trial.     

Pathogenesis of androgenetic alopecia

Although it is universally accepted that dihydrotestosterone causes baldness, how it does so is not well understood. I propose that 3 mechanisms are at work: miniaturization by a dihydrotestosterone-induced acceleration of the mitotic rate of the matrix that leaves less and less time for differentiation; an increased telogen shedding as a result of the shortening of the hair cycles that increases the telogen number per unit of time; and the increased number and duration of the lag phase or kenogen. That this last mechanism is related to dihydrotestosterone is unclear.