Management of androgenetic alopecia

Small molecule agents against alopecia: Potential targets and related pathways

Alopecia has emerged as a global concern, extending beyond the middle-aged and elderly population and increasingly affecting younger individuals. Despite its growing prevalence, the treatment options and effective drugs for alopecia remain limited due to the incomplete understanding of its underlying mechanisms. Therefore, it is urgent to explore the pathogenesis of alopecia and discover novel and safer therapeutic agents. This review provided an overview of the prevailing clinical disorders of alopecia, and the key pathways and targets involved in hair growth process. Additionally, it discusses FDA-approved drugs and clinical candidates for the treatment of alopecia, and explores small molecule compounds with anti-alopecia potential in the drug discovery phase. These endeavors are expected to provide researchers with valuable scientific insights and practical information for anti-alopecia drug discovery.

Compliance to Topical Minoxidil and Reasons for Discontinuation among Patients with Androgenetic Alopecia

INTRODUCTION

This study assessed the levels of compliance to topical minoxidil (TM) among male and female patients with androgenetic alopecia (AGA) and analyzed the factors associated with minoxidil discontinuation.

METHOD

A retrospective study was conducted among 400 consecutive patients with AGA who presented to a dermatology clinic and who were prescribed minoxidil 2% or 5% in the past 5 years. Demographic factors, other previous treatments, and minoxidil parameters including the dose (2% or 5%), total duration of use, treatment results, and side effects were collected.

RESULT

The mean age of the patients was 32.41 years [standard deviation (SD) 8.18], and 66.5% were female. The majority of patients (82.5%) did not receive any previous treatment for AGA. Of the total patients, 345 (86.3%) have discontinued minoxidil. Discontinuation rate showed no association with sex (p = 0.271), age category (p = 0.069), or previous treatment (p = 0.530). Furthermore, the likelihood of minoxidil discontinuation decreased with the increase in treatment duration (p < 0.001) and was significantly lower among patients who reported improvement (69.3%) or stabilization of hair shedding (64.1%) compared with those who reported baby hair (88.9%) or no efficacy (95.3%) (p < 0.001). Furthermore, having experienced an adverse effect of minoxidil was associated with 93.6% discontinuation rate compared with 75.8% in the case of no side effects (p < 0.001). Adjusted analysis showed that minoxidil discontinuation was independently association with longer duration of use [> 1 year; odds ratio (OR) 0.22; p < 0.001], perceived improvement (OR 0.17; p < 0.001) or stabilization (OR 0.14; p < 0.001), and the occurrence of side effects (OR 3.06; p = 0.002).

CONCLUSIONS

The clinical use of TM in AGA is limited by a substantially low compliance even in absence of adverse effects. We emphasize the importance of educating patients regarding the treatment's side effects and the need to use minoxidil for a minimum of 12 months to assess treatment efficacy.

Short-Term Efficacy of Autologous Cellular Micrografts in Male and Female Androgenetic Alopecia: A Retrospective Cohort Study

Purpose

Autologous cellular micrografts (ACM) is a novel treatment method in hair loss, and few data are available regarding its efficacy. The present study was carried out to assess the short-term clinical efficacy of a single application of ACM in the treatment of male and female androgenetic alopecia (AGA).

Materials and Methods

This was a single-center retrospective study involving 140 consecutive adults with confirmed AGA, who received a single session of ACM (Regenera Activa®). Efficacy was evaluated 1–6 months after treatment, by analyzing the change of trichometry parameters, which were assessed using TrichoScan digital image analysis.

Results

Depending on the scalp region, there was increase in mean hair density by 4.5–7.12 hair/cm², average hair thickness by 0.96–1.88 μm, % thick hair by 1.74–3.26%, and mean number of follicular units by 1.30–2.77, resulting in an increase of cumulative hair thickness by 0.48–0.56 unit. Additionally, the frontal region showed a significant decrease in % thin hair (−1.81%, p = 0.037) and yellow dots (−1.93 N/cm², p = 0.003). A favorable response was observed in 66.4% of the participants in the frontal region. Further, a gender-specific effect of treatment was observed.

Conclusion

ACM is a promising treatment in AGA with a short-term favorable response observed in up to approximately two-thirds of patients.

Intradermal injections with 0.5% minoxidil for the treatment of female androgenetic alopecia: A randomized, placebo-controlled trial

Female androgenetic alopecia is one cause of alopecia in women, although the ideal treatment for this condition remains far from defined. The objective of this study was to evaluate the efficacy and safety of intradermal injections with 0.5% minoxidil for the management of female androgenetic alopecia in a randomized, placebo-controlled trial. A total of 54 women diagnosed with female androgenetic alopecia were divided into two groups: one group received intradermal injections of 0.5% minoxidil, and the other received 0.9% saline. Biopsy, trichogram, Trichoscan (Tricholog GmbH, Freiburg, Germany), and self-assessment findings were used to evaluate the outcomes of treatment with minoxidil. In the treated group, there was a significant increase in the terminal-to-vellus hair ratio (P < .001) and in the percentage of anagen hairs (P = .048) and an improvement in hair loss and volume (P = .021 and P = .028, respectively). These results show that intradermal injections with minoxidil were more effective than placebo (P < .001) in the treatment of female androgenetic alopecia with a good safety profile.

Repurposing Kir6/SUR2 Channel Activator Minoxidil to Arrests Growth of Gynecologic Cancers

Gynecologic cancers are among the most lethal cancers found in women, and, advanced stage cancers are still a treatment challenge. Ion channels are known to contribute to cellular homeostasis in all cells and mounting evidence indicates that ion channels could be considered potential therapeutic targets against cancer. Nevertheless, the pharmacologic effect of targeting ion channels in cancer is still understudied. We found that the expression of Kir6.2/SUR2 potassium channel is a potential favorable prognostic factor in gynecologic cancers. Also, pharmacological stimulation of the Kir6.2/SUR2 channel activity with the selective activator molecule minoxidil arrests tumor growth in a xenograft model of ovarian cancer. Investigation on the mechanism linking the Kir6.2/SUR2 to tumor growth revealed that minoxidil alters the metabolic and oxidative state of cancer cells by producing mitochondrial disruption and extensive DNA damage. Consequently, application of minoxidil results in activation of a caspase-3 independent cell death pathway. Our data show that repurposing of FDA approved K⁺ channel activators may represent a novel, safe adjuvant therapeutic approach to traditional chemotherapy for the treatment of gynecologic cancers.

Male pattern baldness and risk of colorectal neoplasia

Background:

Male pattern baldness is positively associated with androgens as well as insulin-like growth factor 1 (IGF-1) and insulin, all of which are implicated in pathogenesis of colorectal neoplasia.

Methods:

From 1992 through 2010, we prospectively followed participants in the Health Professionals Follow-Up Study. Hair pattern at age 45 years was assessed at baseline with five image categories (no baldness, frontal-only baldness, frontal-plus-mild-vertex baldness, frontal-plus-moderate-vertex baldness, and frontal-plus-severe-vertex baldness). Cancer analysis included 32 782 men and used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Restricted to men who underwent at least one endoscopy over the study period, adenoma analysis included 29 770 men and used logistic regressions for clustered data to estimate odds ratios (ORs) and 95% CIs.

Results:

Over the mean follow-up of 15.6 years, 710 cases of colorectal cancer (478 for colon, 152 for rectum, and 80 unknown site) developed. Significantly increased risks associated with frontal-only baldness and frontal-plus-mild-vertex baldness relative to no baldness were observed for colon cancer with respective HR being 1.29 (95% CI, 1.03–1.62) and 1.31 (95% CI, 1.01–1.70). Over the 19-year study period, 3526 cases of colorectal adenoma were detected. Evidence for an increased risk of colorectal adenoma relative to no baldness was significant with frontal-only baldness (OR, 1.16; 95% CI, 1.06–1.26) and borderline insignificant with frontal-plus-severe-vertex baldness (OR, 1.14; 95% CI, 0.98–1.33).

Conclusions:

Subtypes of male pattern baldness at age 45 years were positively associated with colorectal neoplasia. Future studies are warranted to confirm our results and to determine the predictive value of male pattern baldness to identify those at high risk for colorectal neoplasia.

The Relation of Androgenetic Alopecia Severity with Epicardial Fat Thickness

Background

Androgenetic alopecia (AGA) is the most commonly encountered baldness pattern in men. Epicardial fat tissue is found on the cardiac surface between the myocardium and visceral pericardium. Both AGA and epicardial fat thickness (EFT) are related to coronary artery disease, which is also reflected by an increase in carotid intima media thickness (CIMT).

Objective

The purpose of this study was to investigate the relation of AGA severity with EFT.

Methods

One hundred twenty-six male patients with AGA aged 18 to 55 years without histories of chronic disease were enrolled. Subjects were divided into three groups (mild, moderate, and severe) on the basis of the Hamilton baldness scale as modified by Norwood. Maximum EFT was measured at end-systole on the midventricular free wall of the right ventricle. CIMT was also recorded for all patients.

Results

The groups did not have statistically significant differences with respect to age, height, weight, body mass index, left ventricular ejection fraction, or left atrial diameter (p>0.05 for all comparisons), but the severe group had a higher EFT compared with the moderate (p<0.001; z score, -7.040) and mild groups (p<0.001; z score, -6.667). The moderate group also had higher EFT than the mild group (p<0.001; z score, -5.931). Mean CIMT value in the severe group was significantly higher compared with the value in the other groups.

Conclusion

The study showed that subjects in advanced stages of AGA had increased EFT, which was measured via echocardiography.

Perda pilosa por líquen plano pilar após transplante capilar: relato de dois casos e revisão da literatura

Alopecia androgenética é tratada com frequência por meio de microtransplante capilar, téc nica em que os fios transplantados geralmente não caem, pois mantêm características da área doadora, mais resistente. O líquen plano pilar é uma alopecia cicatricial com permanente destruição pilosa. Este artigo relata dois casos de lesões compatíveis com líquen plano pilar em áreas receptora e doadora póstransplante. A dominância da área doadora foi aparentemente sobrepujada pelo líquen plano pilar, que deve ter gerado a queda dos fios. Relatos semelhantes são raros. À suspeita de líquen plano pilar, devese biopsiar o couro cabeludo e evitar o transplante durante a atividade da doença.

Oxidative stress in follicular units during hair transplantation surgery

BACKGROUND

Hair transplantation surgery currently is a well-established procedure in plastic surgery. It consists of harvesting a strip of scalp from the back of the head, then obtaining grafts called follicular units (FUs) from this strip and implanting them in the bald area. The FUs undergo oxidative stress during cold ischemia and after their implantation.

METHODS

Surgery was performed for 18 patients between April and July 2008. Follicular units were preserved in solutions containing different growth-stimulating hormone (GSH) concentrations (5, 10, and 20 mmol). Saline solution was used as a control condition. Spectrophotometry was used to measure the thiobarbituric acid-reactive substance (TBARS) and GSH concentrations before ischemia (control group) in the FUs preserved in the four proposed solutions, then after 30 min of cold ischemia and 30 min after grafting. The data obtained were submitted to analysis of variance, t test, and linear regression analysis.

RESULTS

The TBARS (μmol of malondialdehyde [MDA]/g) and GSH (μmol/g) concentrations were not significantly different between the four solutions in either the ischemia or grafting group. The GSH concentration did not differ significantly between the control (59.801 ± 30.639 μmol/g) and ischemia (56.284 ± 28.404 μmol/g) groups. The GSH concentrations were significantly greater (p < 0.05) in the postgrafting group (63.815 ± 28.404 μmol/g) than in the group subjected to ischemia.

CONCLUSION

Increasing the GSH concentrations used in FU preservation solutions does not reduce the oxidative effects of cold ischemia and reperfusion injury during hair transplantation surgery.

Hair counts in scalp biopsy of males and females with androgenetic alopecia compared with normal subjects

BACKGROUND

Hair counts were studied in scalp biopsy specimens of androgenetic alopecia (AGA) in male and female patients. We also assessed the normal value of hair count in scalp biopsy specimen from Iranians and compared with published data.

METHODS

Thirty subjects with clinically normal scalps, 25 male and 28 female patients with AGA were studied. Vertical and horizontal sections of 4-mm punch biopsy specimens were examined at various levels from the papillary dermis to the subcutis. Hair counts of total, terminal, vellus, anagen and telogen hairs were obtained by ocular micrometer.

RESULTS

Hair counts were not significantly different from published data in American Whites but significantly higher in Iranians compared with Koreans (p < 0.001). There was no significant difference between male and female patients with AGA. Perifollicular inflammation was lower in both the normal subjects and the patients compared with other studies.

CONCLUSION

In AGA patients, total and vellus hairs were lower and terminal to vellus (T:V) ratio was higher than the results of previous studies in Whites (p < 00.1). T:V ratio of control group was significantly higher in this study compared with previous published data. Perhaps the higher ratio than the reported data could means the onset of miniaturization.

Androgens and hair loss

PURPOSE OF REVIEW

Androgenetic alopecia (AGA) or male pattern hair loss is a very common condition that has a significant psychosocial impact for patients. Many advances in the pathogenesis and treatment of AGA have been discovered recently. We discuss the pathogenesis and treatment of AGA.

RECENT FINDINGS

Wide genome analysis showed an association of AGA and chromosome 20pll in addition to androgen-receptor gene. Also, a locus on chromosome 3q26 was found to have a linkage with AGA. Dutasteride has been shown to be more effective than finasteride in the treatment of AGA but is not yet a recommended therapy. In an in-vitro study, a new topical liposomal finasteride formulation showed more than five-fold higher deposition of drug in skin than the corresponding plain drug solution.

SUMMARY

These recent developments in the field of AGA hold some promise and may play a role in the future management.

Androgenetic alopecia

Androgenetic alopecia (AGA), or male pattern hair loss, affects approximately 50% of the male population. AGA is an androgen-related condition in genetically predisposed individuals. There is no treatment to completely reverse AGA in advanced stages, but with medical treatment (eg, finasteride, minoxidil, or a combination of both), the progression can be arrested and partly reversed in the majority of patients who have mild to moderate AGA. Combination with hair restoration surgery leads to best results in suitable candidates. Physicians who specialize in male health issues should be familiar with this common condition and all the available approved treatment options.