A hypothetical pathogenesis model for androgenic alopecia: clarifying the dihydrotestosterone paradox and rate-limiting recovery factors

MitoQ enhances CYP19A1 expression to stimulate WNT/β-catenin signaling pathway for promoting hair growth in androgenetic alopecia

Increased sensitivity to androgens and androgen receptors is the underlying cause of androgenetic alopecia (AGA), a hereditary disease. Our study investigated the preventive effects of MitoQ on dihydrotestosterone (DHT)-induced mitochondrial dysfunction and subsequent hair loss from three perspectives: in vivo, in vitro, and network pharmacology. A mouse model of AGA was used to assess the effectiveness of MitoQ intervention. Seventy-five drug targets and 367 disease targets were identified through network pharmacology analysis. Molecular docking analysis revealed that the androgen receptor (AR) and CYP19A1, which are key targets of MitoQ, may play a role in AGA treatment. CYP19A1 expression was downregulated in lesions from patients with AGA compared to healthy scalp tissue, while AR expression was upregulated. Cellular tests of human dermal papilla cells (DPCs) treated with MitoQ revealed that the mRNA and protein expression of AR remained unchanged, but the mRNA expression of CYP19A1 was upregulated. Our experiments also confirmed that CYP19A1 overexpression prevented DHT-induced apoptosis and upregulated the expression levels of WNT3A and β-catenin, whereas increased apoptosis levels and the downregulation of WNT3A and β-catenin due to CYP19A1 knockdown were reduced by MitoQ. We verified that MitoQ enhanced hair growth in DHT-induced hair loss model mice and reversed DHT-induced apoptosis by enhancing the expression of CYP19A1 in DPCs and that MitoQ may act by mediating the WNT/β-catenin pathway. These findings indicate that MitoQ could be a promising intervention for AGA and that CYP19A1 may serve as a valuable therapeutic target for AGA.

Exploring Mesenchymal Stem Cells versus Minoxidil for Androgenic Alopecia Treatment: A Detailed Animal-Based Histological and Morphometric Study

INTRODUCTION

Androgenic alopecia (AGA), a hair loss condition caused by dihydrotestosterone binding to hair follicle receptors, negatively impacts quality of life for both men and women. Current treatments like minoxidil and finasteride have limitations, highlighting the need for alternative therapies, such as human umbilical cord blood-derived mesenchymal stem cells (HUCB-MSCs).

METHODS

In this study, forty-eight adult male Wistar albino rats (3 months old) were used. The control group (Group I) received no treatment, while the other rats underwent AGA induction via daily subcutaneous testosterone injections (100 mg/kg). These rats developed alopecia and were divided into three groups: AGA (Group II), AGA plus daily minoxidil spray (Group III), and AGA plus a single intradermal injection of HUCB-MSCs (1 mL containing 1 × 105 cells, Group IV). After 4 weeks, the rats were sacrificed, and skin specimens were prepared for histological analysis using H&E, Masson's trichrome, and immunohistochemical staining for CK 19, vascular endothelial growth factor (VEGF), and TUNEL antibodies.

RESULTS

It was shown that HUCB-MSC treatment reversed structural damage to hair and follicles, normalizing conditions within 1-week post-injection. The treatment enhanced the anagen phase, suppressed telogen and catagen phases, reduced apoptosis, and increased VEGF and CK 19 immune reactions. Observational follow-up for Groups III and IV revealed that while the minoxidil group experienced significant hair loss after 37 days, the stem cell group exhibited dense and long hair covering the treated area.

CONCLUSION

HUCB-MSC therapy demonstrated superior efficacy over minoxidil with no observed side effects, indicating its potential as a promising alternative for AGA treatment.

Assessing the efficacy and quality of Life improvements of botulinum toxin type a with topical minoxidil versus topical minoxidil in male androgenetic alopecia: a randomized controlled trial

Androgenetic alopecia (AGA) is a common type of hair loss in men and efficacy and safety of current medical treatment remain limited. Therefore, the present study aimed to investigate the efficacy and safety of botulinum toxin type A (BTA) combined with Minoxidil in patients with AGA. 60 male patients were included in this study and control group received topical 5% Minoxidil and the treatment group received BTA combined with topical 5% Minoxidil. BTA injections (60-70 U) were administered at 30-35 scalp sites. Head photographs were taken at baseline, 2nd, 4th, and 6th months. Clinical descriptions recorded scalp conditions, and patient satisfaction along with Dermatology Life Quality Index scores were documented. The treatment group (TG) showed significant hair growth differences compared to the control group (CG) at the 4th month (P < 0.001) and 6th month (P = 0.0046) post-treatment. TG had improved Investigator Global Assessment (IGA) scores in the 4th month (P = 0.0001) and 6th month (P = 0.0259) compared to CG. Patient satisfaction in TG for hair growth and scalp improvement was higher than CG (all P < 0.05). TG exhibited substantial quality of life improvement at the 4-month (P = 0.0009) and 6-month (P = 0.0099). No adverse reactions were observed post-botulinum toxin injection. BTA combined with Minoxidil effectively promotes hair growth, enhances the quality of life, and alleviates scalp symptoms in male AGA patients at 4th and 6th months, with no adverse effects compared to Minoxidil alone.Trial registration number: Ethics Committee of Shanghai Tongji Hospital (ID: K-2018-026).

The causal relationship between androgenetic alopecia and serum uric acid: A bidirectional Mendelian randomization analysis

BACKGROUND

Despite numerous studies investigating the association between androgenetic alopecia (AGA) and serum uric acid (SUA), the causal relationship between AGA and SUA remains unknown.

METHODS

We utilized bidirectional Mendelian randomization (MR) to explore the causality between AGA and SUA. Our study chose single nucleotide polymorphisms associated with genome-wide significance (p < 5×10-8) for the exposure and showing low linkage disequilibrium (R2 < 0.001) as IVs. Various MR methods were employed to evaluate causality, including inverse-variance weighted (IVW), Weighted Median, MR-Egger, Weighted Mode and Simple Mode. Sensitivity analyses were performed to test the robustness of the results.

RESULTS

Using the IVW method, we did not find a significant causal relationship between AGA and SUA (OR = 1.00, 95% CI 0.99-1.01; p = 0.451). Similarly, the IVW method did not reveal evidence of causality between SUA and AGA (OR = 0.97, 95% CI = 0.91-1.03; p = 0.301). The results from other methods were consistent with those of the IVW approach.

CONCLUSION

The study did not identify a causal relationship between AGA and SUA. Future research should involve larger cohorts and advanced methods to validate the findings and explore the complex interactions between AGA and SUA levels in different populations.

Modelling Human Hair Follicles-Lessons from Animal Models and Beyond

The hair follicle is a specialized appendage of the skin that is critical for multiple functions, including thermoregulation, immune surveillance, and sebum production. Mammals are born with a fixed number of hair follicles that develop embryonically. Postnatally, these hair follicles undergo regenerative cycles of regression and growth that recapitulate many of the embryonic signaling pathways. Furthermore, hair cycles have a direct impact on skin regeneration in homeostasis, cutaneous wound healing, and disease conditions such as alopecia. Here, we review the current knowledge of hair follicle formation during embryonic development and the post-natal hair cycle, with an emphasis on the molecular signaling pathways underlying these processes. We then discuss efforts to capitalize on the field's understanding of in vivo mechanisms to bioengineer hair follicles or hair-bearing skin in vitro and how such models may be further improved to develop strategies for hair regeneration.

Salvianolic Acid B Reduces Oxidative Stress to Promote Hair-Growth in Mice, Human Hair Follicles and Dermal Papilla Cells

Background

Existing research links oxidative stress and inflammation to hair loss. Salvianolic acid B (SAB) is known for its anti-oxidative, anti-inflammatory, and other beneficial pharmacological properties.

Objective

To assess the efficacy of SAB in modulating hair growth.

Methods

In vivo experiments were conducted using C57BL/6 mice to evaluate the effects of SAB on hair and skin parameters. The study involved ex vivo analysis of human hair follicles (HFs) for hair shaft length and hair growth cycle assessment. In vitro, human dermal papilla cells (hDPCs) were cultured with SAB, and their proliferation, protection against H2O2-induced oxidative damage, and gene/protein expression alterations were examined using various analytical techniques, including Real-Time Cell Analysis (RTCA), DCFH-DA Assay, RNA-seq, and KEGG pathway analysis.

Results

SAB treatment in mice significantly improved hair growth and vascularization by day 21. In human HFs, SAB extended hair shaft length and delayed the transition to the catagen phase. SAB-treated hDPCs showed a notable decrease in the expression of oxidation-antioxidation-related genes and proteins, including reduced phosphorylation levels of ERK and p38.

Conclusion

The study indicates that SAB promotes hDPC proliferation and offers protection against oxidative stress, highlighting its potential as a therapeutic agent for enhancing hair growth and treating hair loss.

Androgenetic Alopecia: A Review

This study reviewed the current knowledge on the epidemiology, pathophysiology, clinical presentations, diagnosis, treatment, quality-of-life assessment and recent trends in androgenetic alopecia (AGA). Relevant articles on AGA from PubMed, Google Scholar, Medline and Scopus from 1950 to 2024 were obtained and scrutinized.. Key search words included each term like 'androgenetic alopecia', 'androgenic alopecia', 'pattern baldness' and 'pattern hair loss' AND each term like 'epidemiology', 'pathophysiology', 'genetics', 'hormones', 'micronutrient', 'stress and inflammation', 'growth factors', 'clinical features', 'staging', 'cardiovascular associations', 'diagnosis' and 'management' were used in the search. AGA is a non-scarring hair loss that is exemplified by a progressive decline of hair follicles, or non-functional or dead hair follicles in the scalp in a defined pattern. It is the most common hair loss, more common in men but can also present in younger age as premature AGA. Hormones, genetics, micronutrient deficiency, microinflammation and stress have been implicated, while psychosocial distress and cutaneous correlate of cardiovascular diseases have become sources of relentless research. AGA is a patterned hair loss that is more prevalent in Men. It results from the interactions between hormonal, genetic and other factors which determine the extent of hair loss and associated disorders (psychosocial and cardiovascular). As results of more research become available, the extent of AGA, its comorbidities as well as the full spectrum of their manifestations will continue to be sources of health education and more holistic examination by dermatologists and patients.

Characterization of distinct microbiota associated with androgenetic alopecia patients treated and untreated with platelet-rich plasma (PRP)

BACKGROUND

Androgenic alopecia (AGA) is the most common type of hair loss in men, and there are many studies on the treatment of hair loss by platelet-rich plasma (PRP). The human scalp contains a huge microbiome, but its role in the process of hair loss remains unclear, and the relationship between PRP and the microbiome needs further study. Therefore, the purpose of this study was to investigate the effect of PRP treatment on scalp microbiota composition.

METHODS

We performed PRP treatment on 14 patients with AGA, observed their clinical efficacy, and collected scalp swab samples before and after treatment. The scalp microflora of AGA patients before and after treatment was characterized by amplifying the V3-V4 region of the 16 s RNA gene and sequencing for bacterial identification.

RESULTS

The results showed that PRP was effective in the treatment of AGA patients, and the hair growth increased significantly. The results of relative abundance analysis of microbiota showed that after treatment, g_Cutibacterium increased and g_Staphylococcus decreased, which played a stable role in scalp microbiota. In addition, g_Lawsonella decreased, indicating that the scalp oil production decreased after treatment.

CONCLUSIONS

The findings suggest that PRP may play a role in treating AGA through scalp microbiome rebalancing.

The Biology and Genomics of Human Hair Follicles: A Focus on Androgenetic Alopecia

Androgenetic alopecia is a highly prevalent condition mainly affecting men. This complex trait is related to aging and genetics; however, multiple other factors, for example, lifestyle, are also involved. Despite its prevalence, the underlying biology of androgenetic alopecia remains elusive, and thus advances in its treatment have been hindered. Herein, we review the functional anatomy of hair follicles and the cell signaling events that play a role in follicle cycling. We also discuss the pathology of androgenetic alopecia and the known molecular mechanisms underlying this condition. Additionally, we describe studies comparing the transcriptional differences in hair follicles between balding and non-balding scalp regions. Given the genetic contribution, we also discuss the most significant risk variants found to be associated with androgenetic alopecia. A more comprehensive understanding of this pathology may be generated through using multi-omics approaches.

Assessment of efficacy of different botulinum toxin A concentrations in the treatment of androgenetic alopecia assessed by dermoscopy

BACKGROUND

Androgenetic alopecia (AGA) is the most common type of progressive hair loss in men and women. AGA is characterized by the miniaturization of the hair follicle, leading to the transformation of terminal hair to vellus hair.

OBJECTIVE

To evaluate the efficacy and safety of injecting two different concentrations of botulinum toxin A (BTA) for the treatment of AGA in Egyptian patients.

METHODS

Adult male (Hamilton-Norwood I-VII) and female (Ludwig I-III) patients (N = 32) were assigned to receive two different concentrations BTA (33.3 and 25 U/mL) on each side of the scalp; in total, there were 15 injections administered on each side, with injection volume of 0.1 mL containing 3.3 U for the right half and 2.5 U for the left half. Treatment efficiency was assessed at baseline, Month 3 and Month 6, by degree of clinical improvement and dermoscopy assessment.

RESULTS

By Month 6, proportion of male patients (N = 5) classified as Hamilton-Norwood Grade II increased from 0% to 60% (3/5), proportion of female patients (N = 27) classified as Ludwig Grade I also increased from 14.8% (4/27) to 70% (19/27). Dermoscopy result showed a significant increase in vellus hair density from baseline to Month 6 on the right side (33.3 U/mL), while no change was observed on the left (25 U/mL); however, vellus hair density was higher at Month 3 compared to Month 6. There were changes in yellow spots and peripilar sign more on the right side. Adverse reactions reported include irritation, headache, injections site pain, and nausea.

CONCLUSION

The results of the present study showed that BTA is a safe and effective treatment for AGA in both genders. These findings offer a cutting-edge conceptual structure and therapeutic strategy for the management of AGA in Egyptian population.

Effectiveness and Safety of Hair Growth Formulation Containing Tectona grandis L.f (Teak) Leaf Extract: A Randomized, Double-Blind, Placebo-Controlled Study on Males with Androgenic Alopecia

BACKGROUND

Androgenic alopecia (AGA) is commonly known as male patterned baldness. A high level of dihydrotestosterone (DHT) plays a significant role in AGA development. Inhibition of the enzyme steroid 5-alpha reductase (S5AR), responsible for converting testosterone into DHT, has been shown to delay the progression of AGA. Teak (Tectona grandis L.f) leaf extract exhibited a potent S5AR inhibitory activity. To prove the effectiveness and safety of teak leaf extract as a hair growth promotor, a double-blind, randomized placebo-controlled trial was conducted.

METHODS

Eighty-one AGA subjects were randomly assigned to receive either a hair tonic containing 1% teak leaf extract (HT-teak), 5%minoxidil (positive control), or a placebo administered twice daily, for 24 weeks. Efficacy was assessed through target area hair count (TAHC), anagen-to-telogen ratio (A/T), hair shedding every 4 weeks, and patients' subjective assessments of hair regrowth were assessed at the end of the experiment. Data was analyzed using repeated measure ANOVA.

RESULTS

Both the HT-teak and minoxidil groups exhibited a significant increase in TAHC and A/T, along with a decrease in hair shedding compared to baseline values. Conversely, the placebo group showed no observable signs of hair regrowth. Furthermore, the HT-teak group reported the highest satisfaction scores, and there were no indications of skin irritation or systemic effects on sexual dysfunction and palpitation after 24 weeks of HT-teak application.

CONCLUSION

Teak leaf extract, as incorporated in HT-teak, demonstrates potential as an alternative mild hair growth promoter for individuals with AGA, offering both efficacy and safety.

TRIAL REGISTRATION

This study was retrospectively registered on International Standard Randomised Controlled Trial Number (ISRCTN.com); ISRCTN24541842 (registered on January 8, 2024).

mRNA Levels of Aromatase, 5α-Reductase Isozymes, and Prostate Cancer-Related Genes in Plucked Hair from Young Men with Androgenic Alopecia

Androgenic alopecia (AGA) is the most prevalent type of progressive hair loss and has psychological repercussions. Nevertheless, the effectiveness of current pharmacological treatments remains limited, in part because the molecular basis of the disease has not been fully elucidated. Our group previously highlighted the important roles of aromatase and 5α-reductase (5α-R) in alopecia in young women with female pattern hair loss. Additionally, an association has been proposed between AGA and prostate cancer (PCa), suggesting that genes implicated in PCa would also be involved in AGA. A low-invasive, sensitive, and precise method was used to determine mRNA levels of aromatase, 5α-R isozymes, and 84 PCa-related genes in samples of plucked hair from young men with AGA and controls. Samples were obtained with a trichogram from the vertex scalp, and mRNA levels were quantified using real-time RT-PCR. The men with AGA had significantly higher 5α-R2 mRNA levels in comparison to controls; interestingly, some of them also showed markedly elevated mRNA levels of 5α-R1 or 5α-R3 or of both, which may explain the varied response to 5α-R inhibitor treatments. The men with AGA also showed significant changes versus controls in 6 out of the 84 genes implicated in PCa. This study contributes greater knowledge of the molecular bases of AGA, facilitating early selection of the most appropriate pharmacological therapy and opening the way to novel treatments.

Oral and Topical Administration of a Standardized Saw Palmetto Oil Reduces Hair Fall and Improves the Hair Growth in Androgenetic Alopecia Subjects - A 16-Week Randomized, Placebo-Controlled Study

Purpose

Androgenetic alopecia (AGA) is the most common type of hair loss in humans, affecting self-esteem and emotional well-being. This study aimed to assess the safety and efficacy of VISPOTM, a standardized saw palmetto oil (2-3% β-sitosterol), in subjects with mild-to-moderate AGA.

Methods

In a double-blind, placebo-controlled, four-arm clinical study, 80 healthy male and female subjects aged 18-50 years were randomly allocated (1:1:1:1) to receive either 400 mg capsules of VISPO or 5 mL of a topical formulation containing 20% VISPO or the respective placebo once daily for 16 weeks. The primary endpoints included hair count (hair comb and hair pull tests) and the self-assessment of perceived efficacy. Objective evaluation was performed using the global photographic assessment score. Hair density, thickness, and anagen/telogen ratio were evaluated using phototrichogram analysis.

Results

At the end of the study, oral and topical formulations of VISPO reduced hair fall by up to 29% (p<0.001) and 22.19% (p<0.01) from the baseline, respectively. Hair density increased by 5.17% and 7.61% in the oral and topical VISPO groups, respectively (p<0.001). In addition, oral ingestion of VISPO resulted in a marked reduction in serum dihydrotestosterone (DHT) levels in the subjects compared to placebo (p<0.001). However, the effect of the VISPO formulations on the anagen/telogen ratio was insignificant. No serious adverse effects were observed during the study.

Conclusion

VISPO formulations reduced hair fall and promoted hair regrowth and scalp appearance in AGA patients.

Topically Applied Magnetized Saline Water Activates Autophagy in the Scalp and Increases Hair Count and Hair Mass Index in Men With Mild-to-Moderate Androgenetic Alopecia

Introduction Water is essential for life and is vital for almost all functions of the human body. Recent studies have shown that treating water with magnets can alter its physicochemical properties, including intracluster bonds and water-ion interactions. Magnetized water also undergoes modifications in its physicochemical characteristics, such as pH, salinity, and dissolved oxygen. While there is a significant amount of literature on the use of magnetized water in agricultural settings, research on its potential biomedical applications is still limited. Based on previous findings indicating a potential relationship between autophagy activation and hair loss reversal, a pilot study was designed to explore the effects of topically applied magnetized saline water in patients with androgenetic alopecia. The hypothesis was that the process of water magnetization, which promotes the creation of hydroxyl ions, could potentially induce hair growth through the induction of alkali-induced autophagy in the scalp. Methods We recruited 20 Caucasian men with mild-to-moderate androgenetic alopecia (Norwood-Hamilton stages II-III). Initially, we conducted a 12-week open-label study to evaluate the potential of a topical lotion containing 95% magnetized saline water (2 mL applied once daily) to increase hair count and hair mass index (HMI). Subsequently, we investigated the effect of the lotion on two autophagy markers (Beclin-1 and LC3B) in scalp biopsies from a subgroup of 10 men. Results Hair count significantly increased after 12 weeks of topical treatment with magnetized saline water (from 20.6 ± 9.8 at baseline to 32.5 ± 12.4 at 12 weeks, P < 0.001). Similarly, the mean HMI increased from 37.8 ± 11.4 at baseline to 45.1 ± 13.6 at 12 weeks (P < 0.01). At the molecular level, the topical lotion effectively increased Beclin-1 levels in scalp biopsies by 44% at 12 weeks as compared to the baseline. Similarly, LC3B levels increased by 36% from baseline to 12 weeks, indicating that the lotion effectively activated autophagy in the scalp. Conclusions After 12 weeks of topical treatment, a lotion containing magnetized saline water activated scalp autophagy and significantly increased hair count and HMI in men with mild-to-moderate androgenetic alopecia.

Cell Therapy for Androgenetic Alopecia: Elixir or Trick?

Androgenetic alopecia is the most common cause of hair loss aggravated by increased life pressure, tension, and anxiety. Although androgenetic alopecia (AGA) does not significantly effect physical health, it can have serious negative impact on the mental health and quality of life of the patient. Currently, the effect of medical treatment for AGA is not idealistic, stem cell-based regenerative medicine has shown potential for hair regrowth and follicle repair, but the long-term effect and mechanism of stem cell therapy is not quite explicit. In this review, we summarize the methods, efficacy, mechanism, and clinical progress of stem cell therapies for AGA by now, hope it will present a more comprehensive view in this topic.

A Novel Hair Restoration Technology Counteracts Androgenic Hair Loss and Promotes Hair Growth in A Blinded Clinical Trial

Androgenic alopecia (AGA) is a genetically predetermined condition that occurs as a result of stepwise miniaturization of the dermal papilla. During this process, the hair follicle suffers from increasing malnutrition and eventually dies, causing progressive hair loss. We recently highlighted that HIF-1α modulation may counteract hair loss. Here, we aim to demonstrate the positive influence of Tomorrowlabs HIF strengthening factor [HSF] hair restoration technology on hair biology in a monocentric blinded clinical trial over a total period of 9 months. A trial with 20 subjects (4 female and 16 male) and once-daily application of [HSF] hair restoration technology to the scalp was conducted. To assess the tolerability and efficacy of [HSF], testing included dermatological assessment, determination of hair loss by counting after combing, macro images of the head and TrichoScan evaluation of hair density as well as the proportion of anagen hair versus telogen hair. The clinical data show Tomorrowlabs [HSF] hair restoration to be safe and effective to counteract AGA. The use of Tomorrowlabs [HSF] hair restoration resulted in improvements in the clinical parameters of hair quality such as thickness (+7.2%), hair density (+14.3%) and shine and elasticity (+20.3%) during the test period. The effectiveness of the test product was further determined by a significant reduction in hair loss of an average of 66.8% in treatment-responsive subjects after 6 months and an increase in hair growth reaching up to 32.5%, with an average percentage change of 8.4% in all participants and 10.8% in the responsive patients (85% of the study cohort) after 9 months on TrichoScan evaluation. The hair growth cycle was harmonized with the result of an average anagen hair percentage increase of +8.0% and telogen hair percentage reduction of -14.0% shown in the test area. Applicable for both sexes in an alcohol-free formulation, beneficial to scalp health and free of complications or side effects, this novel product provides objectively measurable results counteracting hair loss paired with an improved look and feel of the hair.

Mechanistic synergy of hair growth promotion by the Avicennia marina extract and its active constituent (avicequinone C) in dermal papilla cells isolated from androgenic alopecia patients

Androgenic alopecia (AGA) is associated with an increased production of 5α-dihydrotestosterone (DHT) by steroid-5α-reductase (5α-R). Crude extracts from Avicennia marina (AM) and its active constituent, avicequinone C (AC), can inhibit 5α-R. We have, herein, explored the potential use of the AM extract and of AC as anti-AGA agents. To this end, we employed human dermal papilla cells (DPCs) isolated from AGA patients' hair that express 5α-R type-1 as well as the androgenic receptor (AR) at high levels. Our in vitro experiments revealed that the AM extract (10 μg/mL) and the AC (10 μM) exhibit multiple actions that interfere with the mechanism that causes AGA. Beside acting as 5α-R inhibitors, both preparations were able to inhibit either the DHT-AR complex formation or its translocation from the cytoplasm into the nucleus (the site of DHT's action). The treatments also increased the gene expression of growth factors in DPCs; these factors play important roles in the angiogenesis associated with hair growth. Moreover, the AM extract suppressed the apoptotic pathway, thereby postponing the initiation of the catagen phase. Taken together, our findings suggest that the AM extract and the AC could serve as natural sources for hair growth promotion and AGA treatment.

Guava (Psidium guajava L.) Leaf Extract as Bioactive Substances for Anti-Androgen and Antioxidant Activities

Leaves of guava (Psidium guajava L.) have been used in Thai folk medicine without any supporting evidence as a traditional herbal remedy for hair loss. Androgenetic alopecia (AGA) is chronic hair loss caused by effects of androgens in those with a genetic predisposition, resulting in hair follicle miniaturization. Our objectives were to provide the mechanistic assessment of guava leaf extract on gene expressions related to the androgen pathway in well-known in vitro models, hair follicle dermal papilla cells (HFDPC), and human prostate cancer cells (DU-145), and to determine its bioactive constituents and antioxidant activities. LC-MS analysis demonstrated that the main components of the ethanolic extract of guava leaves are phenolic substances, specifically catechin, gallic acid, and quercetin, which contribute to its scavenging and metal chelating abilities. The guava leaf extract substantially downregulated SRD5A1, SRD5A2, and SRD5A3 genes in the DU-145 model, suggesting that the extract could minimize hair loss by inhibiting the synthesis of a potent androgen (dihydrotestosterone). SRD5A suppression by gallic acid and quercetin was verified. Our study reveals new perspectives on guava leaf extract's anti-androgen properties. This extract could be developed as alternative products or therapeutic adjuvants for the treatment of AGA and other androgen-related disorders.

Comorbidities in Androgenetic Alopecia: A Comprehensive Review

Androgenetic alopecia is the most common form of hair loss, affecting 85% of men and 40% of women. Androgenetic alopecia is a disease caused by multiple factors, such as genetics, hormones, and systemic diseases; however, the exact cause remains undetermined. Recent studies have found that it is associated with a high incidence of endocrine diseases and other comorbidities. It may not only be a skin disease but also an early signal of underlying systemic diseases. Effective management requires timely diagnosis and treatment initiation. However, in current clinical practice, androgenetic alopecia is still not fully understood or treated. Recognizing the true physical, social, and emotional burden of androgenic alopecia, as well as its associated comorbidities, is the first step in improving the prognosis of affected patients. This review aimed to gather the known pathological factors and provide a reference for clinical physicians to understand androgenetic alopecia and its comorbidities in depth, thereby enabling early recognition of the underlying systemic diseases and providing timely treatment.

Phytochemical Constitution, Anti-Inflammation, Anti-Androgen, and Hair Growth-Promoting Potential of Shallot (Allium ascalonicum L.) Extract

In Thai folklore wisdom, shallot (Allium ascalonicum L.) was applied as a traditional herbal medicine for hair growth promotion with no scientific evidence. Androgenetic alopecia (AGA) is a progressive hair loss caused by multiple factors, including androgen hormones, inflammation, and oxidative stress. Conventional medicines (finasteride, dutasteride, corticosteroids, and minoxidil) have been used with limited therapeutic efficacy and unpleasant side effects. In this study, we aimed to give the first estimation of bioactive compounds in shallot extract and evaluate the hair growth-promoting activities regarding anti-inflammatory and gene expression modulation involving androgen, Wnt/β-catenin, sonic hedgehog, and angiogenesis pathways. The results reveal that phenolic compounds (quercetin, rosmarinic, and p-coumaric acids) are the major constituents of the methanolic shallot extract. Compared with the lipopolysaccharide-stimulated control group (2.68 ± 0.13 µM), nitric oxide production was remarkably diminished by shallot extract (0.55 ± 0.06 µM). Shallot extract improves hair growth promotion activity, as reflected by the downregulation of the androgen gene expression (SRD5A1 and SRD5A2) and the upregulation of the genes associated with Wnt/β-catenin (CTNNB1), sonic hedgehog (SHH, SMO, and GIL1), and angiogenesis (VEGF) pathways. These findings disclose the new insights of shallot extract on hair growth promotions. Shallot extract could be further developed as nutraceutical, nutricosmetic, and cosmeceutical preparations for AGA treatment.

Use of Botulinum Toxin for Androgenic Alopecia: A Systematic Review

In this systematic review, we summarize the efficacy and safety of intradermal and intramuscular botulinum toxin injections for androgenic alopecia (AGA). Using PubMed, we conducted a literature search up to February 2021 using the following keyword combinations: "botulinum toxin" or "botox" and "androgenetic alopecia," "hair loss," or "alopecia." Five clinical studies met our inclusion criteria: 4 prospective cohorts and 1 randomized clinical trial (RCT). Study durations ranged from 24 to 60 weeks. No studies included control groups or compared botulinum toxin injections against approved treatments. A total of 165 participants were identified - all of whom were males with AGA. Of the 4 studies measuring response rates (i.e., subjects with >0% hair changes), response rates ranged from 75 to 79.1%. Within studies measuring hair count changes from intramuscular injections, changes ranged from 18 to 20.9%. No serious adverse events were reported. Studies on botulinum toxin injections have produced favorable outcomes for AGA subjects. However, results should be interpreted with caution due to the absence of control groups, small numbers of participants, and relatively low Jadad quality scores. Large RCTs are recommended to confirm efficacy and safety, explore the effects of botulinum toxin on females with pattern hair loss, and establish best practices for intradermal and intramuscular injection methodologies.

Weekly treatment with SAMiRNA targeting the androgen receptor ameliorates androgenetic alopecia

Androgenetic alopecia (AGA) is the most common type of hair loss in men and women. Dihydrotestosterone (DHT) and androgen receptor (AR) levels are increased in patients with AGA, and DHT-AR signaling correlates strongly with AGA pathogenesis. In this study, treatment with self-assembled micelle inhibitory RNA (SAMiRNA) nanoparticle-type siRNA selectively suppressed AR expression in vitro. Clinical studies with application of SAMiRNA to the scalp and massaging to deliver it to the hair follicle confirmed its efficacy in AGA. For identification of a potent SAMiRNA for AR silencing, 547 SAMiRNA candidates were synthesized and screened. SAMiRNA-AR68 (AR68) was the most potent and could be efficiently delivered to human follicle dermal papilla cells (HFDPCs) and hair follicles, and this treatment decreased the AR mRNA and protein levels. We confirmed that 10 µM AR68 elicits no innate immune response in human PBMCs and no cytotoxicity up to 20 µM with HFDP and HaCaT cells. Clinical studies were performed in a randomized and double-blind manner with two different doses and frequencies. In the low-dose (0.5 mg/ml) clinical study, AR68 was applied three times per week for 24 weeks, and through quantitative analysis using a phototrichogram, we confirmed increases in total hair counts. In the high-dose (5 mg/ml) clinical study, AR68 was given once per week for 24 weeks and showed 83% efficacy in increasing hair counts compared with finasteride. No side effects were observed. Therefore, SAMiRNA targeting AR mRNA is a potential novel topical treatment for AGA.

Antioxidation, Anti-Inflammation, and Regulation of SRD5A Gene Expression of Oryza sativa cv. Bue Bang 3 CMU Husk and Bran Extracts as Androgenetic Alopecia Molecular Treatment Substances

Androgenetic alopecia (AGA), a hair loss disorder, is a genetic predisposition to sensitive androgens, inflammation, and oxidative stress. Unfortunately, current treatments with synthetic medicines contain a restricted mechanism along with side effects, whereas the bioactive constituents of plant extracts are multifunctional, with fewer side effects. The massive amounts of rice husk and bran are agricultural wastes that may cause pollution and environmental problems. Owing to these rationales, the local rice variety, Bue Bang 3 CMU (BB3CMU), which is grown in northern Thailand, was evaluated for the valuable utilization of rice by-products, husk (BB3CMU-H) and bran (BB3CMU-RB) extracts, for AGA treatment regarding antioxidant, anti-inflammatory, anti-androgenic activities, and the characterization of bioactive compounds. Our study verified that BB3CMU-H had the highest level of polyphenols, contributing to its greater antioxidant activity. Conversely, BB3CMU-RB was the predominant source of tocopherols, resulting in better anti-androgenic activities regarding the downregulation of steroid 5α-reductase genes (SRD5A). Notably, anti-inflammation via the attenuation of nitric oxide productions was observed in BB3CMU-H (0.06 ± 0.13 μM) and BB3CMU-RB (0.13 ± 0.01 μM), which were significantly comparable to diclofenac sodium salt (0.13 ± 0.19 μM). Therefore, the combination of BB3CMU-H and BB3CMU-RB could be utilized in cosmeceutical and pharmaceutical applications for AGA patients.

Alleviation of Androgenetic Alopecia with Aqueous Paeonia lactiflora and Poria cocos Extract Intake through Suppressing the Steroid Hormone and Inflammatory Pathway

Paeonia lactiflora Pallas (PL) and Poria cocos Wolf (PC) have been traditionally used to treat inflammatory diseases reported in Dongui Bogam and Shen Nong Ben Cao Jing, traditional medical books in Korean and China, respectively. We determined the efficacies and the molecular mechanisms of PL, PC, and PL + PC aqueous extracts on androgenetic alopecia (AGA) induced by testosterone propionate in C57BL/6 mice. The molecular mechanisms of PL and PC in AGA treatment were examined using experimental assays and network pharmacology. The AGA model was generated by topically applying 0.5% testosterone propionate in 70% ethanol solution to the backs of mice daily for 28 days while the normal-control (Normal-Con; no AGA induction) mice applied 70% ethanol. The 0.1% PL (AGA-PL), 0.1% PC (AGA-PC), 0.05% PL + 0.05% PC (AGA-MIX), and 0.1% cellulose (AGA-Con; control) were supplemented in a high-fat diet for 28 days in AGA-induced mice. Positive-control (AGA-Positive) were administered 2% finasteride daily on the backs of the AGA mice. Hair growth rates decreased in the order of AGA-PL, AGA-MIX, AGA-PC, AGA-Positive, and AGA-Con after 21 days of treatment (ED21). On ED28, skins were completely covered with hair in the AGA-PL and AGA-MIX groups. Serum testosterone concentrations were lower in the AGA-PL group than in the AGA-Con group and similar to concentrations in the Normal-Con group, whereas serum 17β-estradiol concentrations showed the opposite pattern with increasing aromatase mRNA expression (p < 0.05). In the dorsal skin, DKK1 and NR3C2 mRNA expressions were significantly lower, but TGF-β2, β-Catenin, and PPARG expressions were higher in the AGA-PL and AGA-PC groups than in the AGA-Con group (p < 0.05), whereas TNF-α and IL-6 mRNA expressions were lower in the AGA-PL, AGA-MIX, and Normal-Con groups than in the AGA-Con group (p < 0.05). The phosphorylation of Akt and GSK-3β in the dorsal skin was lower in AGA-Con than normal-Con, and PL and MIX ingestion suppressed their decrease similar to the Normal-Con. In conclusion, PL or PL + PC intake had beneficial effects on hair growth similar to Normal-Con. The promotion was related to lower serum testosterone concentrations and pro-inflammatory cytokine levels, and inhibition of the steroid hormone pathway, consistent with network pharmacology analysis findings.

A Cross-sectional Study of Plasma Trace Elements and Vitamins Content in Androgenetic Alopecia in Men

Androgenetic alopecia (AGA) is the most common variant of male pattern baldness in which occurrence and development of multiple genetic, hormonal, and metabolic factors are involved. We aimed to estimate plasma element content (Mg, Ca, Zn, Cu, Se, Fe), vitamin status (B12, D, E, and folic acid) in patients with AGA using direct colorimetric tests or atomic absorption spectrometry, and the influence of these parameters in the formation of various hair loss patterns. The study included 50 patients with I-IV stages of AGA divided into two groups with normal and high levels of dihydrotestosterone compared with 25 healthy individuals. The presence of two patterns of pathological hair loss in the androgen-dependent (parietal) and androgen-independent (occipital) areas of the scalp was confirmed. It was shown that all patients with AGA have a deficiency of elements (Zn, Cu, Mg, Se) and vitamins (B12, E, D, folic acid). However, the hair loss rate was not due to their content. А positive interrelation between quantitative trichogram parameters in the occipital region and iron metabolism in pairs "hair density vs Fe" and "hair diameter vs ferritin" was shown. In turn, in the parietal region, an inverse correlation of hair diameter with plasma Cu level was found, the most pronouncing in patients with high levels of dihydrotestosterone. The obtained results indicate the importance of multiple micronutrient deficiencies in the AGA occurrence accompanied by the existence of two different hair loss patterns, differently related to the content of certain trace elements and androgens in the blood.

HIF-1α Stimulators Function Equally to Leading Hair Loss Agents in Enhancing Dermal Papilla Growth

INTRODUCTION

Androgenic alopecia (AGA) occurs due to progressive miniaturization of the dermal papilla (DP). During this process the hair follicle loses nutrition over time and eventually dies, causing the hair to fall out. Recent evidence suggests that hypoxia-inducible factor-1a (HIF-1α) modulation may counteract hair loss. This study aims to evaluate the proliferation of dermal papilla cells (DPCs) under the influence of a selection of commercially available topical hair loss drugs, compared to HIF-1α-stimulating agents.

MATERIALS AND METHODS

Using the hanging drop method, DPCs self-organized into spheroid shape, mirroring the three-dimensional (3D) structure of the DP in vivo. DP analogs were treated with established substances against AGA (minoxidil and caffeine) compared to HIF-1α-stimulating agents (deferoxamine [DFO] and deferiprone [DFP]), at 10 mM doses. DP analogs were simultaneously stained with 5-bromo-2'-deoxyuridine (BrdU) to evaluate impact of drug compounds on DP daughter cell production. Concurrently, fluorescent microscopy visualization of migration of daughter cells after 48 h in culture was performed.

RESULTS

DPC proliferation within the spheroid structure was significantly enhanced by caffeine, minoxidil, and the HIF-1α-stimulating agent DFP when compared to control. Highest proliferation was seen in the DFP-treated DP analogs. Migration of peripheral DP daughter cells was highest in control and DFO groups.

CONCLUSION

Here we demonstrate a significantly enhanced proliferative activity for both established substances against AGA (minoxidil and caffeine) and the HIF-1α-stimulating agent DFP in a 3D DPC spheroid culture model with equal results for DFP and minoxidil. These favorable characteristics make such compounds potential water-soluble alternatives to minoxidil.

Characteristics of healthy and androgenetic alopecia scalp microbiome: Effect of Lindera strychnifolia roots extract as a natural solution for its modulation

OBJECTIVE

The human scalp harbours a vast community of microbiotal mutualists. Androgenetic alopecia (AGA), the most common form of hair loss in males, is a multifactorial condition involving genetic predisposition and hormonal changes. The role of microflora during hair loss remains to be understood. After having characterized the scalp microbiota of 12 healthy male subjects and 12 AGA male subjects (D0), the aim of this investigation was to evaluate the capacity of Lindera strychnifolia root extract (LsR) to restore a healthy bacterial and fungal scalp microflora after 83 days (D83) of treatment.

MATERIAL AND METHODS

The strategy used was based on high-throughput DNA sequencing targeting the encoding 16S ribosomal RNA for bacteria and Internal Transcribed Spacer 1 ribosomal DNA for fungi.

RESULTS

Test analysis of relative abundance comparing healthy and AGA subjects showed a significant increase of Cutibacterim acnes (P < 0.05) and Stenotrophomonas geniculata (P < 0.01) in AGA subjects. AGA scalp condition was also associated with a significant (P < 0.05) decrease of Staphylococcus epidermidis relative abundance. A lower proportion of Malassezia genus in samples corresponding to AGA scalps and an increase of other bacterial genera (Wallemia, Eurotium) were also noted. At the species level, mean relative abundance of Malassezia restricta and Malassezia globosa were significantly lower (P < 0.05) in the AGA group. Eighty-three days of treatment induced a significant decrease in the relative abundance of C. acnes (P < 0.05) and S. geniculata (P < 0.01). S. epidermidis increased significantly (P < 0.05). At the same time, LsR treatment induced a significant increase in the proportion of M. restricta and M. globosa (P < 0.05).

CONCLUSION

Data from sequencing profiling of the scalp microbiota strongly support a different microbial composition of scalp between control and AGA populations. Findings suggest that LsR extract may be a potential remedy for scalp microbiota re-equilibrium.

A comprehensive review of biochemical factors in herbs and their constituent compounds in experimental studies on alopecia

ETHNOPHARMACOLOGICAL RELEVANCE

Alopecia is a chronic condition that may cause emotional and psychological distress to patients, which may significantly impact a patient's quality of life. As conventional treatments have only a transient therapeutic effect and result in unwanted side effects, many patients have attempted to find therapeutic herbs or compounds that function as safer and more potent treatments for alopecia. Many such herbs have been used in complementary and alternative medicine (CAM) for centuries; however, there is a lack of information on the therapeutic mechanisms of herbs used for the treatment of alopecia.

AIM OF THE STUDY

The aim of this review was to perform a critical assessment of the methods and results of experimental studies related to alopecia and to provide the potential mechanisms of action of herbs and their constituent compounds used in the identified studies, in particular, in relation to the stages of the cell cycle. We hope to better guide the clinical application and scientific research of herbs for the treatment of alopecia.

MATERIALS AND METHODS

We reviewed experimental studies to determine the methods used and the mechanism of action of the herbs and constituent compounds. Databases, including Medline (via PubMed), EMBASE, OASIS, and RISS, were searched for the following keywords: "medicinal plants," "alopecia," "alopecia areata," "androgenetic alopecia," "animal experiment," and "in vitro study." We also assessed the risks of bias, toxicity, and taxonomy to determine the quality of information.

RESULTS

C57BL/6 mice and human dermal papilla cells were the most commonly used models for in vivo and in vitro studies, respectively. Many herbs and their constituent compounds were used to treat alopecia by managing the hair cycle, keratinocyte proliferation, apoptosis, angiogenesis, hormones, and inflammation. These compounds prolong the anagen phase, shorten the transition from the telogen to phase anagen, and inhibit premature catagen phase.

CONCLUSIONS

This review has further elucidated the therapeutic mechanisms of herbs and their constituent compounds that are relevant to alopecia and discussed the effectiveness of using herbal treatments. There is a need to develop evidence regarding the quality control, taxonomy, and toxicology of these compounds. Such improvements will provide a better quality of evidence to ensure the efficacy and safety of herbs and compounds used for the treatment of alopecia.

Topical ketoconazole for the treatment of androgenetic alopecia: A systematic review

Androgenetic alopecia (AGA) is common and associated with significant psychosocial distress. Treatment options are needed for patients that do not adequately respond to first line treatments of finasteride or minoxidil. Topical ketoconazole has been proposed as a promising treatment. The goal of this systematic review was to evaluate the efficacy of topical ketoconazole in the treatment of AGA. A systematic literature search was conducted within the MEDLINE database using the key terms "ketoconazole" and "alopecia." Forty-seven papers were screened for inclusion, of which nine were assessed for eligibility. Seven articles were included in the qualitative synthesis, including two animal studies (total of 40 participants) and five human studies (total of 318 participants). Murine studies demonstrated a significant increase in mean ratio of hair regrowth to denuded area in the ketoconazole treatment groups compared to controls. Human studies reported increased hair shaft diameter following ketoconazole use. One study reported a significant increase in pilary index (percent anagen phase × diameter) following treatment. Studies also demonstrated clinical improvement of AGA based on photographic assessment and subjective evaluation. Topical ketoconazole is a promising adjunctive or alternative therapy in the treatment of AGA. Randomized controlled trials are needed.

Androgenetic alopecia: combing the hair follicle signaling pathways for new therapeutic targets and more effective treatment options

Introduction: In the past 30 years, only two drugs have received FDA approval for the treatment of androgenetic alopecia reflecting a lack of success in unraveling novel targets for pharmacological intervention. However, as our knowledge of hair biology improves, new signaling pathways and organogenesis processes are being uncovered which have the potential to yield more effective therapeutic modalities. Areas covered: This review focuses on potential targets for drug development to treat hair loss. The physiological processes underlying the promise of regenerative medicine to recreate new functional hair follicles in bald scalp are also examined. Expert opinion: The discovery of promising new targets may soon enable treatment options that modulate the hair cycle to preserve or extend the growth phase of the hair follicle. These new targets could also be leveraged to stimulate progenitor cells and morphogenic pathways to reactivate miniaturized follicles in bald scalp or to harness the potential of wound healing and embryogenic development as an emerging paradigm to generate new hair follicles in barren skin.

Cholesterol homeostasis: Links to hair follicle biology and hair disorders

Lipids and lipid metabolism are critical factors in hair follicle (HF) biology, and cholesterol has long been suspected of influencing hair growth. Altered cholesterol homeostasis is involved in the pathogenesis of primary cicatricial alopecia, mutations in a cholesterol transporter are associated with congenital hypertrichosis, and dyslipidaemia has been linked to androgenic alopecia. The underlying molecular mechanisms by which cholesterol influences pathways involved in proliferation and differentiation within HF cell populations remain largely unknown. As such, expanding our knowledge of the role for cholesterol in regulating these processes is likely to provide new leads in the development of treatments for disorders of hair growth and cycling. This review describes the current state of knowledge with respect to cholesterol homeostasis in the HF along with known and putative links to hair pathologies.

Self-Assessments of Standardized Scalp Massages for Androgenic Alopecia: Survey Results

Introduction

Standardized scalp massages (SSMs) improve hair thickness in nonbalding men, but their effects on androgenic alopecia (AGA) have not yet been evaluated. The objective of this study was to investigate the effect of SSMs on self-assessed AGA sufferers (SAGASs).

Methods

Between October 2016 and October 2017, 1899 SAGASs searching online for hair loss treatments beyond AGA management drugs accessed literature explaining SSMs as a potential therapy for AGA, then watched a demonstration video detailing twice-daily, 20-min SSMs segmented by three rotational scalp regions using hand-generated presses, pinches, and stretches. In December 2017, SAGASs were contacted once to participate in a retrospective survey study to assess SSM adherence and hair changes. Age, gender, hair loss region and gradient, diet, supplement and topical use, AGA management drug use, estimations for minutes daily and months of massaging, and self-perceived hair changes were reported. Some participants also submitted photosets documenting hair changes throughout SSM adherence.

Results

A total of 340 (17.9%) respondents completed the survey, and 327 (17.2%) reported attempting the SSMs. SSM participants reported a median daily massage effort of 11–20 min and mean adherence of 7.4 ± 6.6 months, with 68.9% reporting hair loss stabilization or regrowth. Estimated minutes daily, months, and total SSM effort (i.e., minutes daily × months) were positively associated with self-perceived hair changes. On average, perceived hair loss stabilization and regrowth occurred after 36.3 h of SSM effort. Results did not vary across age, gender, Norwood gradient, or concomitant supplement, topical, finasteride, minoxidil, or microneedling use. However, hair change improvements were marginally lower for participants reporting diffuse versus frontal/temporal or vertex thinning.

Conclusions

While further research is warranted, these results align with previous findings and suggest the potential for SSMs to improve AGA.

Electronic supplementary material

The online version of this article (10.1007/s13555-019-0281-6) contains supplementary material, which is available to authorized users.