Minoxidil: a comprehensive review

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.

Atroposelective Synthesis of Biaryl N-Oxides via Cu-Catalyzed De Novo Heteroaromatic N-Oxide Ring Formation

Heteroaromatic N-oxides, renowned for their highly polar N─O bond and robust structure, exhibit significant bioactivities and have played a pivotal role in various drug development projects since the discovery of Minoxidil. Moreover, heteroaromatic N-oxides, featuring axially chiral biaryl frameworks, are indispensable as Lewis base catalysts and ligands in organic synthesis. Despite their importance, synthesizing these chiral compounds is challenging, necessitating chiral starting materials or resolution processes. Catalytic strategies rely on the functionalization of heteroaromatic N-oxide compounds, leading to products with a relatively limited skeletal diversity. This study introduces a Cu-catalyzed atroposelective method for synthesizing biaryl N-oxides via de novo heteroaromatic N-oxide ring formation. This mild and efficient approach achieves excellent stereoselectivities (up to 99:1 er), enabling the production of a wide array of N-oxides with novel heteroaromatic scaffolds. The axially chiral N-oxide product 3f demonstrates high stereoselectivity and recyclability as a Lewis base catalyst. Additionally, product 3e exhibits promising therapeutic efficacy against triple-negative breast cancer, with IC50 values of 4.8 and 5.2 µm in MDA-MB-231 and MDA-MB-468 cells, respectively. This research not only advances the synthesis of challenging chiral heteroaromatic N-oxides but also encourages further exploration of N-oxide entities in the discovery of bioactive small molecules.

Cellulose nanocrystal-stabilized Pickering emulsion gels as vehicles for follicular delivery of minoxidil

Minoxidil (MXD) is the only topical over-the-counter medicine approved by the United States Food and Drug Administration for the treatment of androgenetic alopecia. For the purpose of targeting the delivery of MXD to dermal papilla in the hair follicle, MXD Pickering emulsion gels were fabricated based on the designability of deep eutectic solvent (DES) and the versatility of cellulose nanocrystal (CNC) and sodium carboxymethyl cellulose (CMC-Na). Structural studies and theoretical calculations results suggest that CNC can stabilize the interface between the MXD-DES and water, leading to the formation of Pickering emulsions. The rheological properties and stabilities of MXD Pickering emulsions were enhanced through gelation using CMC-Na, which highlights the good compatibility and effectiveness of natural polysaccharides in emulsion gels. Due to the particle size of emulsion droplets (679 nm) and the rheological properties of emulsion gel, the fabricated MXD formulations show in vivo hair regrowth promotion and hair follicle targeting capabilities. Interestingly, the MXD Pickering emulsion-based formulations exert therapeutic effects by upregulating the expression of hair growth factors. The proposed nanodrug strategy based on supramolecular strategies of CNC and CMC-Na provides an interesting avenue for androgenetic alopecia treatment.

Trilayer dissolving microneedle for transdermal delivery of minoxidil: a proof-of-concept study

Alopecia areata (AA) is a chronic autoimmune disease characterized by bald patches in certain areas of the body, especially the scalp. Minoxidil (MNX), as a first-line treatment of AA, effectively induces hair growth. However, oral and topical administration pose problems, including low bioavailability, risk of uncontrolled hair growth, and local side effects such as burning hair loss, and scalp irritation. In the latest research, MNX was delivered to the skin via microneedle (MN) transdermally. The MNX concentration was distributed throughout the needle so that drug penetration was reduced and had the potential to irritate. In this study, we formulated MNX into three-layer dissolving microneedles (TDMN) to increase drug penetration and avoid irritation. Physicochemical evaluation, parafilm, was used to evaluate the mechanical strength of TDMN and showed that TDMN could penetrate the stratum corneum. The ex-vivo permeation test showed that the highest average permeation result was obtained for TDMN2, namely 165.28 ± 31.87 ug/cm2, while for Minoxidil cream it was 46.03 ± 8.5 ug/cm2. The results of ex vivo and in vivo dermatokinetic tests showed that the amount of drug concentration remaining in the skin from the TDMN2 formula was higher compared to the cream preparation. The formula developed has no potential for irritation and toxicity based on the HET-CAM test and hemolysis test. TDMN is a promising alternative to administering MNX to overcome MNX problems and increase the effectiveness of AA therapy.

Hybrid hair follicle stem cell extracellular vesicles co-delivering finasteride and gold nanoparticles for androgenetic alopecia treatment

Androgenetic alopecia (AGA) is a non-fatal disease prevalent worldwide. However, mixed efficacy has been observed among different therapies for hair regrowth in AGA patients. Thus, a nano-platform with synergistic treatments based on a hybrid extracellular vesicle encapsulating gold nanoparticles (AuNPs) and finasteride (Hybrid/Au@Fi) was constructed through membrane fusion between hair follicle stem cell (HFSC)-derived extracellular vesicles and liposomes. These hybrid vesicles (HVs) not only fuel hair regrowth by providing cellular signals in extracellular vesicles, but also improve storage stability, follicle retention, and drug encapsulation efficiency (EE%) for finasteride inhibiting 5α-reductase, and nano-size AuNPs that simulate low-level laser therapy (LLLT) with similar photothermal effects in vitro. The EE% of finasteride in these HVs reached 45.33%. The dual administration of these extracellular vesicles and finasteride showed a strong synergistic effect on HFSCs in vitro. In an AGA mouse model, once-daily topical Hybrid/Au@Fi (115.07 ± 0.32 nm, -7.50 ± 1.68 mV) gel led to a faster transition of hair follicles (HFs) from the catagen to the anagen, increased hair regrowth coverage, and higher quality of regrowth hair, compared to once-daily 5% minoxidil treatment. Compared to topical minoxidil, the multifaceted synergistic therapy of Hybrid/Au@Fi through topical administration offers a new option for intractable AGA patients with low side effects.

Application of Non-Pharmacologic Therapy in Hair Loss Treatment and Hair Regrowth

Purpose

Alopecia significantly affects the appearance and psychology of patients, and pharmacological therapies and hair transplantation are the main treatments for alopecia, but both have limitations. This review aimed to summarize the non-pharmacological therapies that promote hair growth and regeneration.

Patients and Methods

This is a non-systematic review. Multiple databases was searched with relevant data published between 1997 and 2024. Searching and screening followed the PRISMA guidelines.

Results

Novel therapeutic modalities, such as gas molecules, platelet-rich plasma, laser, and microneedling, can change the microenvironment of hair follicles, activate hair follicle stem cells, and promote hair growth and regeneration.

Conclusion

This paper reviews research on the application of non-pharmacological therapies in alopecia treatment and hair regeneration, with a view to providing an important basis for future research on alopecia treatment and the postoperative treatment of patients after hair transplantation.

Engineered Exosomes Biopotentiated Hydrogel Promote Hair Follicle Growth via Reprogramming the Perifollicular Microenvironment

Androgenetic alopecia (AGA) is a highly prevalent condition in contemporary society. The conventional treatment of minoxidil tincture is hindered by issues such as skin irritation caused by ethanol, non-specific accumulation in hair follicles, and short retention due to its liquid form. Herein, we have developed a novel minoxidil-incorporated engineered exosomes biopotentiated hydrogel (Gel@MNs) that has the capability to modulate the perifollicular microenvironment for the treatment of AGA. Leveraging the exceptional skin penetration abilities of flexible liposomes and the targeting properties of exosomes, the encapsulated minoxidil can be effectively delivered to the hair follicles. In comparison to free minoxidil, Gel@MNs demonstrated accelerated hair regeneration in an AGA mouse model without causing significant skin irritation. This was evidenced by an increase in both the number and size of hair follicles within the dermal layer, enhanced capillary formation surrounding the follicles, and the regulation of the transition of hair follicle cells from the telogen phase to the anagen growth phase. Therefore, this safe and microenvironment-modifying hybrid exosome-embedded hydrogel shows promising potential for clinical treatment of AGA.

Chemical approaches to the sulfation of small molecules: current progress and future directions

Sulfation is one of the most important modifications that occur to a wide range of bioactive small molecules including polysaccharides, proteins, flavonoids, and steroids. In turn, these sulfated molecules have significant biological and pharmacological roles in diverse processes including cell signalling, modulation of immune and inflammation response, anti-coagulation, anti-atherosclerosis, and anti-adhesive properties. This Essay summarises the most encountered chemical sulfation methods of small molecules. Sulfation reactions using sulfur trioxide amine/amide complexes are the most used method for alcohol and phenol groups in carbohydrates, steroids, proteins, and related scaffolds. Despite the effectiveness of these methods, they suffer from issues including multiple-purification steps, toxicity issues (e.g., pyridine contamination), purification challenges, stoichiometric excess of reagents which leads to an increase in reaction cost, and intrinsic stability issues of both the reagent and product. Recent advances including SuFEx, the in situ reagent approach, and TBSAB show the widespread appeal of novel sulfating approaches that will enable a larger exploration of the field in the years to come by simplifying the purification and isolation process to access bespoke sulfated small molecules.

Can Plant Extracts Help Prevent Hair Loss or Promote Hair Growth? A Review Comparing Their Therapeutic Efficacies, Phytochemical Components, and Modulatory Targets

This narrative review aims to examine the therapeutic potential and mechanism of action of plant extracts in preventing and treating alopecia (baldness). We searched and selected research papers on plant extracts related to hair loss, hair growth, or hair regrowth, and comprehensively compared the therapeutic efficacies, phytochemical components, and modulatory targets of plant extracts. These studies showed that various plant extracts increased the survival and proliferation of dermal papilla cells in vitro, enhanced cell proliferation and hair growth in hair follicles ex vivo, and promoted hair growth or regrowth in animal models in vivo. The hair growth-promoting efficacy of several plant extracts was verified in clinical trials. Some phenolic compounds, terpenes and terpenoids, sulfur-containing compounds, and fatty acids were identified as active compounds contained in plant extracts. The pharmacological effects of plant extracts and their active compounds were associated with the promotion of cell survival, cell proliferation, or cell cycle progression, and the upregulation of several growth factors, such as IGF-1, VEGF, HGF, and KGF (FGF-7), leading to the induction and extension of the anagen phase in the hair cycle. Those effects were also associated with the alleviation of oxidative stress, inflammatory response, cellular senescence, or apoptosis, and the downregulation of male hormones and their receptors, preventing the entry into the telogen phase in the hair cycle. Several active plant extracts and phytochemicals stimulated the signaling pathways mediated by protein kinase B (PKB, also called AKT), extracellular signal-regulated kinases (ERK), Wingless and Int-1 (WNT), or sonic hedgehog (SHH), while suppressing other cell signaling pathways mediated by transforming growth factor (TGF)-β or bone morphogenetic protein (BMP). Thus, well-selected plant extracts and their active compounds can have beneficial effects on hair health. It is proposed that the discovery of phytochemicals targeting the aforementioned cellular events and cell signaling pathways will facilitate the development of new targeted therapies for alopecia.

Application of validated UV spectrophotometric and colorimetric method to quantify minoxidil in the development of trilayer dissolving microneedle: Proof of concept in ex vivo and in vivo studies in rats

Alopecia areata (AA) is an autoimmune-induced hair loss condition, by utilizing MNX, a hair growth-promoting compound. However, minoxidil (MNX) administration's efficacy is hindered by low bioavailability and adverse effects. To enhance its delivery, Trilayer Dissolving Microneedles (TDMN) are introduced, enabling controlled drug release. The study's primary was to establish a validated UV-Vis Spectrophotometer method for Minoxidil analysis in rat skin affected by alopecia areata. This method adheres to International Conference Harmonization (ICH) and FDA guidelines, encompassing accuracy, precision, linearity, quantification limit (QL), and detection limit (DL). The validation method was conducted through two approaches, namely UV region validation using PBS and the colorimetric method in the visible region (Vis). The validated approach is then employed for assessing in vitro release, ex vivo permeation, and in vivo pharmacokinetics. Results indicate superior MNX extraction recovery using methanol compared to acetonitrile. Method C (5mL methanol) is optimal, offering high recovery with minimal solvent usage. Precision assessments demonstrate %RSD values within MNX guidelines (≤15%), affirming accuracy and reproducibility. UV-Vis spectroscopy quantifies MNX integration into TDMN, using PVA-PVP, with concentrations aligning with ICH standards (95% to 105%). In conclusion, TDMN holds promise for enhancing MNX delivery, mitigating bioavailability and side effect challenges. The validated UV-Vis Spectrophotometer method effectively analyzes MNX in skin tissues, providing insights into AA treatment and establishing a robust analytical foundation for future studies.

Toxicity of minoxidil - Comprehensive in silico prediction of main toxicity endpoints: Acute toxicity, irritation of skin and eye, genetic toxicity, health effect, cardiotoxicity and endocrine system disruption

This article focusses on elucidating the toxicological profile of minoxidil, a widely used pharmacological agent for alopecia, through the application of in silico methods (Percepta ACD/Labs software). This research is driven by the need to understand key toxicological endpoints: acute toxicity, skin and eye irritation, genetic toxicity, cardiotoxicity, disruption of the endocrine system, and estimation of various health effects due to the lack of experimental data for this drug. These parameters are critically evaluated to meet the stringent requirements of the pharmaceutical industry's safety assessments. The results obtained for acute toxicity (LD50 for rats and mouse) indicate that minoxidil exhibits a species-dependent acute toxicity profile e.g. 51 mg/kg bw for intravenous administration in mice. The predicted health effects indicate a 93% risk to the gastrointestinal system, 54% for the kidneys, 52% for the liver, 42% for the blood and lungs, and 39% for the cardiovascular system. The prediction of genotoxicity suggests a moderate probability (48%) of inducing a positive Ames test result. Furthermore, moderate inhibition of the hERG channel indicates potential cardiac risks of Minoxidil. Based on the information obtained, we propose subjecting minoxidil to additional toxicological assessments. The successful adoption of these in silico methodologies aligns with the 3 R s principle (replacement, reduction, and refinement) in the field of modern toxicological studies of minoxidil, all without the use of laboratory animals for the novelty of our toxicity assessment.

Medicinal Chemistry of Drugs with N-Oxide Functionalities

Molecules with N-oxide functionalities are omnipresent in nature and play an important role in Medicinal Chemistry. They are synthetic or biosynthetic intermediates, prodrugs, drugs, or polymers for applications in drug development and surface engineering. Typically, the N-oxide group is critical for biomedical applications of these molecules. It may provide water solubility or decrease membrane permeability or immunogenicity. In other cases, the N-oxide has a special redox reactivity which is important for drug targeting and/or cytotoxicity. Many of the underlying mechanisms have only recently been discovered, and the number of applications of N-oxides in the healthcare field is rapidly growing. This Perspective article gives a short summary of the properties of N-oxides and their synthesis. It also provides a discussion of current applications of N-oxides in the biomedical field and explains the basic molecular mechanisms responsible for their biological activity.

Synergistic therapeutic effect of ginsenoside Rg3 modified minoxidil transfersomes (MXD-Rg3@TFs) on androgenic alopecia in C57BL/6 mice

Inflammation in hair follicles will reduce the effectiveness of minoxidil (MXD) in the treatment of androgen alopecia (AGA) caused by elevated androgen levels. To target multiple physiological and pathological processes in AGA, a novel natural bioactive compound modified transfersomes (MXD-Rg3@TFs) was prepared to replace cholesterol that may disrupt hair growth, with ginsenosides Rg3 (Rg3) that have anti-inflammatory effects on AGA. The effects of MXD, Rg3 and their combination on AGA were evaluated using dihydrotestosterone (DHT) induced human dermal papilla cells (DPCs), and the results showed that the combination of MXD and Rg3 can significantly promote the proliferation, reduce the level of intracellular ROS and inflammatory factors, and inhibit the aging of DHT induced DPCs. Compared with cholesterol membrane transfersomes (MXD-Ch@TFs), MXD-Rg3@TFs has similar deformability, smaller particle size and better stability. MXD-Rg3@TFs has also significant advantages in shortening telogen phase and prolonging the growth period of hair follicles in C57BL/6 mice than MXD-Ch@TFs and commercial MXD tincture. The prominent ability of MXD-Rg3@TFs to inhibit the conversion of testosterone to DHT and reduce the level of inflammatory factors suggested that Rg3 and MXD in MXD-Rg3@TFs have synergistic effect on AGA therapy. MXD-Ch@TFs with no irritation to C57BL/6 mice skin is expected to reduce the dose of MXD and shorten the treatment time, which would undoubtedly provide a promising therapeutic option for treatment of AGA.

Minoxidil Nanosuspension-Loaded Dissolved Microneedles for Hair Regrowth

Minoxidil (MIN) is used topically to treat alopecia. However, its low absorption limits its use, warranting a new strategy to enhance its delivery into skin layers. The objective of this study was to evaluate the dermal delivery of MIN by utilizing dissolved microneedles (MNs) loaded with MIN nanosuspension (MIN-NS) for hair regrowth. MIN-NS was prepared by the solvent-antisolvent precipitation technique. The particle size of MIN-NS was 226.7 ± 9.3 nm with a polydispersity index of 0.29 ± 0.17 and a zeta potential of -29.97 ± 1.23 mV. An optimized formulation of MIN-NS was selected, freeze-dried, and loaded into MNs fabricated with sodium carboxymethyl cellulose (Na CMC) polymeric solutions (MIN-NS-loaded MNs). MNs were evaluated for morphology, dissolution rate, skin insertion, drug content, mechanical properties, ex vivo permeation, in vivo, and stability studies. MNs, prepared with 14% Na CMC, were able to withstand a compression force of 32 N for 30 s, penetrate Parafilm M® sheet at a depth of 374-504 µm, and dissolve completely in the skin within 30 min with MIN %recovery of 95.1 ± 6.5%. The release of MIN from MIN-NS-loaded MNs was controlled for 24 h. MIN-NS-loaded MNs were able to maintain their mechanical properties and chemical stability for 4 weeks, when kept at different storage conditions. The in vivo study of the freeze-dried MIN-NS and MIN-NS-loaded MNs proved hair regrowth on rat skin after 11 and 7 days, respectively. These results showed that MIN-NS-loaded MNs could potentially improve the dermal delivery of MIN through the skin to treat alopecia.

Microneedle Delivery Platform Integrated with Codelivery Nanoliposomes for Effective and Safe Androgenetic Alopecia Treatment

Although topical application of minoxidil is a widely used, FDA-approved therapy for androgenetic alopecia (AGA) treatment, it suffers from low bioavailability, the requirement for frequent long-term use, and side effects. With a similar structure as minoxidil, kopexil and kopyrrol are less toxic and have been commercialized, but show an inferior hair regeneration effect compared to minoxidil. Herein, we developed a hyaluronic acid (HA)-based dissolvable microneedles (MNs) delivery platform integrated with kopexil and kopyrrol coencapsulated nanoliposomes (KK-NLPs) to effectively and safely treat AGA. Facilitated by nanoliposomes and MNs, the encapsulated KK-NLPs performed efficient skin penetration and enhanced cellular internalization into human dermal papilla cells. Furthermore, within the target cells, the codelivered kopexil and kopyrrol show synergistic effects by orchestrating an upregulation in the expression of Ki67, β-catenin, vascular endothelial growth factor (VEGF), and CD31. These molecular responses collectively foster cell proliferation, migration, and antioxidative effects, thereby facilitating the expedited progression of hair follicles (HFs) into the anagen phase and promoting peripheral angiogenesis. Notably, the KK-NLPs-integrated MNs treatment group exhibits noteworthy enhanced hair regeneration in vivo, with identical or superior therapeutic effects at a much lower dosage than that of minoxidil. These results suggest the great potential of this kopexil and kopyrrol codelivery nanoliposomes-integrated MNs platform for AGA treatment in a safe and efficient way.

Topical minoxidil reported hair discoloration: a cross-sectional study

Minoxidil is a widely utilized medication androgenic alopecia. An original investigation on its potential to cause hair darkening in treated people is lacking. We conducted an observational study using two face-validated questionnaires that dermatologists altered to assess minoxidil's hair discolouration risk. This Saudi Arabian survey collected data in October and November 2022. One questionnaire targeted the population, while the other targeted dermatologists. Survey 1 included 453 patients, 56.7% of whom were 18-24 and mostly female. It's interesting that 26% (n=118) detected hair greying and 14.8% (n=67) noticed other color changes. With P-values of 0.0001, longer-term minoxidil users and those with a family history of hair greying had higher hair discolouration. Dermatologists completed Survey 2 (57 participants). Nearly 60% of dermatologists have ten years of experience. 42.1% of dermatologists saw grey hair after minoxidil use. 17.5% of doctors blame minoxidil for hair graying. This observational study examined the data of over 400 patients to determine if minoxidil could cause hair discoloration. Based on the data, we hypothesize that this drug may cause hair discoloration with prolonged use and in people with a family history of hair greying.

Incorporating surfactants into PCL microneedles for sustained release of a hydrophilic model drug

Polymeric microneedles (MNs) are widely used for sustained drug release due to their distinct advantages over other types of MNs. Poly-ε-caprolactone (PCL) stands out as a biodegradable and biocompatible hydrophobic polymer commonly employed in drug delivery applications. This study explores the impact of surfactants on the encapsulation and release rate of a model hydrophilic drug, minoxidil (MXD), from PCL MNs. Three nonionic surfactants, Tween 80, Span 60, and polyethylene glycol (PEG), were integrated into PCL MNs at varying concentrations. Compared to the other types of surfactants, PEG-containing PCL MNs exhibit enhanced insertion capabilities into a skin-simulant parafilm model and increased mechanical strength, suggesting facile penetration into the stratum corneum. Furthermore, MXD-PEG MNs show the highest encapsulation efficiency and are further characterized using FTIR, DSC and XRD. Their mechanical strength against different static forces was measured. The MNs exhibit a sustained release pattern over 20 days. Eventually, MXD-PEG MNs were subjected to penetration testing using chicken skin and required minimal insertion forces with no observed MN failure during experimentation even after compression with the maximum force applied (32 N per patch). Taken together, the present work demonstrates the feasibility of incorporating nonionic surfactants like PEG into the tips of hydrophobic PCL MNs for sustained delivery of a model hydrophilic drug. This formulation strategy can be used to improve patient compliance by allowing self-administration and achieving prolonged drug release.

Comparison of Efficacy of Topical Betamethasone Dipropionate and Topical Minoxidil in Patients With Alopecia Areata

Background and objective Alopecia areata (AA) is a reiterative and nonscarring type of hair loss that can affect any hairy area of the body, particularly the scalp. It manifests as patchy or confluent hair loss with variations in demographics and ethnicity. There are numerous treatment options available, including topical and systemic steroids, topical minoxidil, dithranol, tacrolimus, psoralen and ultraviolet therapy (PUVA), contact immunotherapy, and oral immunosuppressive drugs. However, no previous contrast for efficacy is present between the topical betamethasone versus topical minoxidil alone in our population. This study aims to compare the efficacy of topical betamethasone dipropionate versus topical minoxidil in patients with AA. Methodology A nonrandomized controlled study was conducted at the Department of Dermatology, Jinnah Hospital Lahore, incorporating the data of patients between July 26, 2016, and January 26, 2017, after obtaining institutional ethical approval. One hundred patients with alopecia, either on the scalp or any other hairy part, from both genders, aged between 18 and 50 years, were included in the study. Two groups were created, and patients were assigned to these groups based on the clinician's choice. Group A patients were administered betamethasone dipropionate (0.05%) lotion twice daily on affected areas for 12 weeks. Group B patients were administered minoxidil (5%) solution twice daily on affected areas for 12 weeks. A four-week follow-up plan was followed. A five-point scale score system was used for alopecia grading. After 12 weeks, the hair regrowth score (RGS) was used to compare the efficacy of treatment between the two groups. Results A total of 100 patients with grades S1 to S3 AA of less than three months duration were enrolled. Two groups were created, with 50 patients in each group. The mean age in Group A was 29.08 ± 6.51 years, while in Group B, it was 29.38 ± 6.62 years. In Group A, there were 76% males and 24% females, while in Group B, there were 74% males and 26% females. Comparison of efficacy of topical betamethasone dipropionate versus topical minoxidil in patients with AA demonstrated a greater efficacy of 74% (Grade 3 and Grade 4 responses) in Group A, while in Group B, only 42% of patients showed efficacy. A statistically significant difference was found, with a P-value of 0.001. No serious side effects were noted. Conclusions Our study concluded that topical betamethasone dipropionate (0.05%) lotion has statistically significantly higher efficacy compared to topical minoxidil (5%) solution in patients with AA.

Successful topical minoxidil treatment for hair density and length in trichorhinophalangeal syndrome type 1

A 9-year-old girl presented with slow hair growth and hair thinning since birth. Additionally, she had short stature and abnormally short fingers; genetic testing confirmed the diagnosis of trichorhinophalangeal syndrome (TRPS) type 1. After 4 months of topical minoxidil treatment, hair density and length significantly improved diffusely throughout the scalp without evidence of hypertrichosis. This case underscores the therapeutic potential of topical minoxidil for TRPS, paving the way for improved patient quality of life.

Clinical efficacy and safety of low-dose oral minoxidil versus topical solution in the improvement of androgenetic alopecia: A randomized controlled trial

BACKGROUND

Topical minoxidil is the recommended first-line pharmacologic treatment for male and female pattern hair loss. However, low-dose oral minoxidil has been used off-label with good clinical efficacy and safety.

AIM

To compare the effectiveness and safety of topical minoxidil as a first-choice treatment of androgenetic alopecia versus 1 mg daily oral minoxidil.

METHOD

Sixty-five AGA patients were randomly allocated to receive either 5% topical solution or 1 mg/day oral minoxidil for 6 months. Treatment efficacy was evaluated by measuring hair diameter, photographic assessment, and patient self-assessment questionnaires. The safety of treatment was checked through history taking and physical examination.

RESULTS

Both topical and oral minoxidil groups showed significant improvement in hair diameter after 6 months of treatment (p < 0.001). However, there was no significant difference between the two groups. The photographic assessment demonstrated a significant improvement in hair density in the topical minoxidil group in all marked points located at 12 cm (p = 0.025), 16 cm (p = 0.034), and 24 cm (p = 0.014) distance from the glabella but not in the oral minoxidil group. Nevertheless, the difference between the two groups was not significant. In each group, over 60% of patients expressed satisfaction with their treatments, and no significant difference was detected between the two groups.

CONCLUSION

Although topical minoxidil has a better overall therapeutic effect than 1 mg oral minoxidil, the difference between the two groups was not significant. Therefore, 1 mg oral minoxidil may be as effective and safe as standard topical minoxidil in female and male pattern hair loss.

Efficacy and safety of low-dose oral minoxidil in the management of androgenetic alopecia

INTRODUCTION

Treating alopecia can be challenging. The available treatments are topical minoxidil, low-dose oral minoxidil (LDOM), and 5-α reductase inhibitors like finasteride and dutasteride. Only topical minoxidil and finasteride 1 mg daily are FDA-approved, while the rest are used off-label. Recent research has suggested that oral minoxidil may be a safe and effective treatment for both female androgenetic alopecia (female AGA) and male androgenetic alopecia (male AGA).

AREAS COVERED

In this review, we explore the pharmacokinetics, mechanism of action, safety, and efficacy of oral minoxidil. Additionally, we discuss its effectiveness compared to other treatments available for female AGA and male AGA.

EXPERT OPINION

LDOM has demonstrated a favorable efficacy and safety profile in several trials. Subsequently, its use for the treatment of male AGA and female AGA is increasing. However, its use remains off-label, and through increased usage, we will get a better idea of the best dosage and monitoring guidelines. LDOM has also been used with some effectiveness in other forms of hair loss.

The homing of exogenous hair follicle mesenchymal stem cells into hair follicle niches

Hair loss is a debilitating condition associated with the depletion of dermal papilla cells (DPCs), which can be replenished by dermal sheath cells (DSCs). Hence, strategies aimed at increasing the populations of DPCs and DSCs hold promise for the treatment of hair loss. In this study, we demonstrated in mice that introduced exogenous DPCs and DSCs (hair follicle mesenchymal stem cells) could effectively migrate and integrate into the dermal papilla and dermal sheath niches, leading to enhanced hair growth and prolonged anagen phases. However, the homing rates of DPCs and DSCs were influenced by various factors, including recipient mouse depilation, cell passage number, cell dose, and immune rejection. Through in vitro and in vivo experiments, we also discovered that the CXCL13/CXCR5 pathway mediated the homing of DPCs and DSCs into hair follicle niches. This study underscores the potential of cell-based therapies for hair loss by targeted delivery of DPCs and DSCs to their respective niches and sheds light on the intriguing concept that isolated mesenchymal stem cells can home back to their original niche microenvironment.

Efficacy and safety of combinational therapy using topical minoxidil and microneedling for the treatment of androgenetic alopecia: a systematic review and meta-analysis

Androgenetic alopecia is a widespread condition that is the most common type of hair loss affecting approximately 58% and 40% of men and women by the age of 50, respectively. Patients have been known to experience severe distress due to androgenetic alopecia, including anxiety, low self-esteem, and depression. The objective of this study was to conduct a systematic review and meta-analysis to determine the efficacy of combination therapy using topical minoxidil and microneedling compared to topical minoxidil alone. This systematic review of randomized controlled trials was carried out using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. The literature search was performed using Scopus, Cochrane, Embase, and the National Institutes of Health's United States National Library of Medicine from inception through January 20, 2023. Randomized controlled trials examining the efficacy of combinational therapy and monotherapy using microneedling and minoxidil on patients with clinically diagnosed androgenetic alopecia were included after screening titles, abstracts, and full texts. Two independent reviewers selected studies, extracted data, and appraised the risk of bias using the Cochrane risk of bias assessment tool. Ten randomized controlled trials, including 466 patients, were selected for this review and eight studies were ultimately included in the meta-analysis. All eight studies displayed a statistically significant increase in total hair count [standard mean difference (SMD) 1.76; 95% CI 1.26-2.26; P < 0.00001]; however, the evidence did not support a statistically significant increase in hair diameter (SMD 0.82; 95% CI - 0.01 to 1.65; P = 0.05). No scarring nor serious adverse events were reported in any of the studies. The findings of this meta-analysis strongly support the utilization of a multimodal therapeutic approach of minoxidil and microneedling for hair growth in patients with androgenetic alopecia. However, variations in factors such as rating scale measurements, microneedling methods, and areas of treatment may have resulted in confounding. Further randomized controlled, large-sample trials employing rigorous methodologies are needed to gain a more comprehensive understanding regarding treatment efficacy, namely the impact of combinational therapy on hair diameter.Clinical trial registrations This study follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and is registered in the International Prospective Register of Systematic Reviews (PROSPERO) database (CRD42023391164) and the International Platform of Registered Systematic Review and Meta-analysis Protocols (INPLASY) database (INPLASY202310031).

Toxicological assessment of minoxidil: A drug with therapeutic potential besides alopecia

Minoxidil is regularly prescribed for alopecia, and its therapeutic potential has expanded in recent times. However, few studies have been conducted to evaluate its toxicity, and controversial findings regarding its mutagenic activities remain unsolved. This study aimed to access cytotoxic, genotoxic, and mutagenic properties of minoxidil using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay, comet assay, and micronucleus test in mouse fibroblast (L929) cells and its point mutation induction potential in the Salmonella/microsome assay. Furthermore, an in vivo toxicity assessment was conducted in Caenorhabditis elegans. Minoxidil showed cytotoxicity at 2.0 mg/mL in MTT assay. Genotoxicity was observed after 3 h treatment in L929 cells using comet assay. No mutagenic effect was observed in both the micronucleus test and the Salmonella/microsome assay. The lethal dose 50 in C. elegans was determined to be 1.75 mg/mL, and a delay in body development was detected at all concentrations. In conclusion, minoxidil induces DNA damage only in early treatment, implying that this DNA damage may be repairable. This observation corroborates the absence of mutagenic activities observed in L929 cells and Salmonella typhimurium strains. However, the toxicity of minoxidil was evident in both C. elegans and L929 cells, underscoring the need for caution in its use.

Low-Dose Oral Minoxidil for Alopecia: A Comprehensive Review

Low-dose oral minoxidil (LDOM) has demonstrated a promising safety and efficacy profile in the treatment of various hair disorders, including male androgenetic alopecia (AGA) and female-pattern hair loss (FPHL); however, it lacks FDA approval. The usual LDOM starting dose for male AGA is 1-5 mg/day, depending on physician preference and the patient's condition. For FPHL, it is 0.5-1 mg/day. The maximum dose is generally 5 mg/day. If patients respond well without major side effects, the dose may be gradually increased since the LDOM's efficacy appears to be dose-dependent. Patients may use LDOM long term if the treatment outcome is satisfactory. The common side effects of LDOM are hypertrichosis and cardiovascular symptoms. Females are more prone to hypertrichosis than males. The side effects of LDOM can be categorized as (a) dose-dependent type A side effects (hypertrichosis and cardiovascular symptoms) and (b) idiosyncratic type B side effects (pericardial effusion). Minoxidil acts via multiple pathways. Although minoxidil has a relatively short half-life of around 4 h, its hypotensive effect may last approximately 72 h. Effective treatments for alopecia are limited. Therefore, LDOM could be an important addition to the available therapies for managing some hair disorders, including AGA.

An international expert consensus statement focusing on pre and post hair transplantation care

AIM

To achieve international expert consensus and give recommendations on best practices in hair transplantation surgery, focusing on pre- and post-transplantation care.

METHODS

A modified Delphi method was used to reach consensus. An international scientific committee developed an 81-statement questionnaire. A panel of 38 experts in hair transplantation from 17 countries across 4 continents assessed the questionnaire.

RESULTS

Two consensus rounds were carried out, with 59 out of 81 statements (73%) reaching consensus. Expert recommendations emphasize the correct selection of candidates for hair transplantation and the need for patients to have received adequate medical treatment for alopecia before transplant. Comorbidities should be assessed and considered while planning surgery, and an individualized plan for perioperative care should be drawn up before transplant. Certain medications associated with increased risk of bleeding should be withdrawn before surgery. Specific recommendations for post-transplantation care are given. After transplantation, patients should gradually resume their normal haircare regimen. Close follow-up should be carried out during the first year after transplant.

CONCLUSIONS

This study presents numerous consensus-based recommendations on general aspects of hair transplantation, including candidate selection, medical therapy prior to transplantation, anesthesia, and resuming haircare after transplantation.

Athena: Specialty Certificate Examination case for formulation and systemic therapy

This Athena details the case of a 53-year-old woman with ongoing hair loss who was taking several medications.

Signaling pathways in hair aging

Hair follicle (HF) homeostasis is regulated by various signaling pathways. Disruption of such homeostasis leads to HF disorders, such as alopecia, pigment loss, and hair aging, which is causing severe health problems and aesthetic concerns. Among these disorders, hair aging is characterized by hair graying, hair loss, hair follicle miniaturization (HFM), and structural changes to the hair shaft. Hair aging occurs under physiological conditions, while premature hair aging is often associated with certain pathological conditions. Numerous investigations have been made to determine the mechanisms and explore treatments to prevent hair aging. The most well-known hypotheses about hair aging include oxidative stress, hormonal disorders, inflammation, as well as DNA damage and repair defects. Ultimately, these factors pose threats to HF cells, especially stem cells such as hair follicle stem cells, melanocyte stem cells, and mesenchymal stem cells, which hamper hair regeneration and pigmentation. Here, we summarize previous studies investigating the above mechanisms and the existing therapeutic methods for hair aging. We also provide insights into hair aging research and discuss the limitations and outlook.

Co-delivery of minoxidil and tocopherol acetate ethosomes to reshape the hair Follicular Microenvironment and promote hair regeneration in androgenetic alopecia

The most prevalent kind of hair loss is androgenic alopecia (AGA), which is characterized by hair follicle miniaturization and microenvironment dysfunction. Although topical Minoxidil (MXD) was considered to be a safe and effective treatment for AGA, excess reactive oxygen species (ROS) and lower sulfotransferase activity in the hair follicular microenvironment led to an unsatisfactory treatment of AGA. Here, we developed the ethosome (MTE) load of minoxidil and tocopherol acetate to improve the therapeutic effect of MXD on androgenic alopecia. It could regulate the microenvironment around hair follicles, promote the telogen-to-anagen transition of hair follicles, and boost hair regeneration, thus achieving a synergistic effect of 1 + 1 > 2. The results proved that MTE showed excellent stability, biosafety, and good dermal and follicular permeability in vitro. The hair regeneration ability of AGA model mice showed that the co-delivery ethosome might regulate the microenvironment around the hair follicles and improve hair regeneration in comparison to the commercial minoxidil tincture alone. As a result, the strategy provided a promising new strategy for the treatment of AGA.

Caco-2 Cell Line Standardization with Pharmaceutical Requirements and In Vitro Model Suitability for Permeability Assays

The Caco-2 cell line derived from human colon carcinoma is commonly used to assess the permeability of compounds in in vitro conditions. Due to the significant increase in permeability studies using the Caco-2 cell line in recent years, the need to standardize this biological model seems necessary. The pharmaceutical requirements define only the acceptance criteria for the validation of the Caco-2 cell line and do not specify the protocol for its implementation. Therefore, the aim of this study is to review the conditions for permeability studies across the Caco-2 monolayer reported in the available literature concerning validation guidelines. We summarized the main aspects affecting the validation process of the Caco-2 cell line, including the culture conditions, cytotoxicity, cell differentiation process, and monolayer transport conditions, and the main conclusions may be useful in developing individual methods for preparing the cell line for validation purposes and further permeability research.

Comprehensive Study of Drug-Induced Pruritus Based on Adverse Drug Reaction Report Database

Drug-induced pruritus triggers a desire to scratch, thereby diminishing one's quality of life. Certain instances of this phenomenon follow complex mechanisms of action that diverge from histamine-mediated pathways, known contributors to pruritus. However, investigations into the relationship between drugs and pruritus are limited. In this study, data mining techniques were employed to comprehensively analyze the characteristics of drugs linked to pruritus, using the FDA's Adverse Event Reporting System (FAERS) data. Reports linked to pruritus demonstrated noteworthy differences in gender, age, and weight when compared with non-pruritus cases. Among the leading candidates for drugs prompting pruritus were ophthalmic drugs, systemic antibacterials, contrast media, dermatological antifungals, and dermatological preparations. A principal component analysis showed that the second principal component served as an indicator for distinguishing between onsets at mucous membranes or the skin's surface. Additionally, the third principal component functioned as an indicator for categorizing administration methods as either invasive or noninvasive. Furthermore, a hierarchical cluster analysis conducted on these obtained principal components revealed the potential for classifying drugs based on the site of pruritus onset and the method of drug administration. These findings contribute to the development of targeted prevention and treatment strategies for avoiding pruritus in clinical practice.

Biotherapeutic Applications of Platelet-Rich Plasma in Regenerative Medicine

BACKGROUND

Platelet-rich plasma (PRP), a blood-based product containing platelets and growth factors, is being utilized to treat numerous non-hemostatic disorders. Studies have explored the use of PRP to provide rapid repair, healing, and recovery from various injuries; some studies mentioned the effectiveness of PRP as compared with other forms of treatment like the use of hyaluronic acid. Commercially available PRP systems are available now, and each varies from one another depending on how it is prepared, thus causing variations in platelet concentration and growth factor content. These variations also implicated different therapeutic applications.

METHODS

The paper reviews the various applications of PRP, including factors to consider before using PRP therapy, and provides an extensive list of PRP applications.

RESULTS

The administration of PRP as a standalone treatment or as a co-therapy results in observed positive outcomes. However, there is a lack of standardization for PRP preparation, increasing the risks for heterogeneity and bias amongst results.

CONCLUSION

The use of PRP is indeed an option for regenerative therapy, but more research is needed before it can fully be recommended as a primary treatment modality.

Dissolving microneedles for alopecia treatment

Alopecia is a treatable benign disease, however, approximately 15-30% of women and 50% of men suffer from alopecia, which greatly affects patient's self-esteem and quality of life. Currently, commercial products for alopecia treatment include topical minoxidil solution, oral finasteride tablets and oral baricitinib tablets. However, the barrier of stratum corneum, systemic adverse effects and poor cure rate limit the application of commercial products. Therefore, researchers investigated the mechanism of alopecia, and developed new drugs that could target lactate dehydrogenase-related pathways, remove excessive reactive oxygen in hair follicles, and reduce the escape of hair follicle stem cells, thus injecting new strength into the treatment of alopecia. Moreover, starting from improving drug stratum corneum penetration and reducing side effects, researchers have developed hair loss treatment strategies based on dissolved microneedles (MNs), such as drug powders/microparticles, nanoparticles, biomimetic cell membranes, phototherapy and magnetically responsive soluble microneedles, which show exciting alopecia treatment effects. However, there are still some challenges in the practical application of the current alopecia treatment strategy with soluble microneedles, and further studies are needed to accelerate its clinical translation.

New Target for Minoxidil in the Treatment of Androgenetic Alopecia

Objective

To investigate the mechanism of minoxidil in treating androgenetic alopecia (AGA).

Methods

The mechanism of action of minoxidil on AGA was first systematically investigated from the viewpoint of network pharmacology, including minoxidil-AGA target prediction, protein-protein interaction (PPI) network analysis, molecular docking and enrichment analysis of targets related to minoxidil and AGA, and dermal papilla cell assays to confirm the viability of prediction.

Results

The combined analysis revealed that minoxidil treatment of AGA not only acts on androgenic receptors (AR) but also on 2 new targets, steroid 17-alpha-hydroxylase/17,20 lyase (CYP17A1) and aromatase (CYP19A1). The biological processes linked to these targets were concentrated on several pathways, including enzymes and hormones. Further experiments have revealed that minoxidil suppresses the expression of AR and CYP17A1, boosts the activity of CYP19A1, decreases the formation and binding of dihydrotestosterone, and enhances the production of estradiol. Through these changes, minoxidil acts as a treatment for AGA.

Conclusion

Minoxidil may act by altering hormonal and enzymatic pathways. Our study finds two new targets (CYP17A1, CYP19A1) of minoxidil and demonstrates that minoxidil inhibits AR. These targets may provide new ideas for drug research.

Treatment of Androgenetic Alopecia: Current Guidance and Unmet Needs

Androgenetic alopecia (AGA) is the most common cause of hair loss in men and women. Traditionally, topical minoxidil and oral finasteride have been the standard of care yielding mixed results. New treatments such as Low-Level Laser Therapy (LLLT), microneedling, platelet-rich plasma (PRP), and others have been extensively studied in the literature, and the purpose of this review is to provide a comprehensive discussion of the latest treatment methods and their efficacy in treating AGA. Novel therapies such as oral minoxidil, topical finasteride, topical spironolactone, botulinum toxin, and stem cell therapy offer interesting alternatives to standard of care therapies for patients. In this review, we present data from recent studies on the clinical efficacy of these treatments. Furthermore, as new treatments have emerged, clinicians have tested combination therapies to assess whether there may be a synergistic relationship between multiple modalities. While there has been a great increase in the treatments available for AGA, the quality of evidence varies greatly and there is still a great need for randomized double blinded clinical trials to adequately assess the clinical efficacy of some treatments. While PRP and LLLT have demonstrated encouraging results, standardized treatment protocols are needed to adequately inform clinicians on how to use such therapies. Given the abundance of new therapeutic options, clinicians and patients must weigh the benefits and risks of each treatment option for AGA.

Innovative Strategies for Hair Regrowth and Skin Visualization

Today, about 50% of men and 15-30% of women are estimated to face hair-related problems, which create a significant psychological burden. Conventional treatments, including drug therapy and transplantation, remain the main strategies for the clinical management of these problems. However, these treatments are hindered by challenges such as drug-induced adverse effects and poor drug penetration due to the skin's barrier. Therefore, various efforts have been undertaken to enhance drug permeation based on the mechanisms of hair regrowth. Notably, understanding the delivery and diffusion of topically administered drugs is essential in hair loss research. This review focuses on the advancement of transdermal strategies for hair regrowth, particularly those involving external stimulation and regeneration (topical administration) as well as microneedles (transdermal delivery). Furthermore, it also describes the natural products that have become alternative agents to prevent hair loss. In addition, given that skin visualization is necessary for hair regrowth as it provides information on drug localization within the skin's structure, this review also discusses skin visualization strategies. Finally, it details the relevant patents and clinical trials in these areas. Together, this review highlights the innovative strategies for skin visualization and hair regrowth, aiming to provide novel ideas to researchers studying hair regrowth in the future.

In Vitro Drug Repurposing: Focus on Vasodilators

Drug repurposing aims to identify new therapeutic uses for drugs that have already been approved for other conditions. This approach can save time and resources compared to traditional drug development, as the safety and efficacy of the repurposed drug have already been established. In the context of cancer, drug repurposing can lead to the discovery of new treatments that can target specific cancer cell lines and improve patient outcomes. Vasodilators are a class of drugs that have been shown to have the potential to influence various types of cancer. These medications work by relaxing the smooth muscle of blood vessels, increasing blood flow to tumors, and improving the delivery of chemotherapy drugs. Additionally, vasodilators have been found to have antiproliferative and proapoptotic effects on cancer cells, making them a promising target for drug repurposing. Research on vasodilators for cancer treatment has already shown promising results in preclinical and clinical studies. However, additionally research is needed to fully understand the mechanisms of action of vasodilators in cancer and determine the optimal dosing and combination therapy for patients. In this review, we aim to explore the molecular mechanisms of action of vasodilators in cancer cell lines and the current state of research on their repurposing as a treatment option. With the goal of minimizing the effort and resources required for traditional drug development, we hope to shed light on the potential of vasodilators as a viable therapeutic strategy for cancer patients.

Laser and light therapy combined with topical minoxidil for alopecia areata: a systematic review and meta-analysis of randomized controlled trials

We aim to evaluate the clinical efficacy and safety of using laser and light combined with topical minoxidil for alopecia areata. We searched PubMed, Embase, Web of Science, the Cochrane Library, China National Knowledge Infrastructure (CNKI), China Biomedical Literature Database (CBM), VIP database, and Wanfang Data from their inception to September 18, 2022. The risk of bias of the included RCTs was assessed by the Cochrane Collaboration tool. RevMan 5.3 software and Stata 14.0 software were used to perform the statistical analysis. The GRADE system assessed the quality of evidence. Ten studies were enrolled finally. The results of the meta-analysis showed that compared with topical minoxidil alone, the 308-nm excimer laser/light or He-Ne laser combined with topical minoxidil could reduce the SALT (Severity of Alopecia Tool) score (MD= -5.88, 95% CI [-9.79, -1.98], P=0.003). Whether fractional CO₂ laser (RR=1.29, 95% CI [1.14, 1.46], P<0.0001), 308-nm excimer laser/light (RR=1.32, 95% CI [1.12, 1.55], P=0.001), He-Ne laser (RR=1.69, 95% CI [1.07, 2.69], P=0.03), or NB-UVB (RR=1.35, 95% CI [1.07,1.70], P=0.01) combined with topical minoxidil may improve the treatment response rate, comparing with topical minoxidil only. The recurrence rate of laser and light combined with topical minoxidil was lower than that of the minoxidil alone group (RR=0.54, 95% CI [0.31, 0.93], P=0.03) when follow-up time was 1 year. In addition, the incidence of adverse events including irritant contact dermatitis, erythema, desquamation, pain, and pruritus was no significant difference between the two groups (RR=1.50, 95% CI [0.95, 2.36], P=0.08). The level of evidence for outcomes was classified as very low to moderate. Based on the available evidence, laser and light combined with topical minoxidil therapy may be effective and safe for alopecia areata. However, more high-quality trials are required for comprehensive analysis and further verification.

Integrative and Mechanistic Approach to the Hair Growth Cycle and Hair Loss

The hair cycle is composed of four primary phases: anagen, catagen, telogen, and exogen. Anagen is a highly mitotic phase characterized by the production of a hair shaft from the hair follicle, whereas catagen and telogen describe regression and the resting phase of the follicle, respectively, ultimately resulting in hair shedding. While 9% of hair follicles reside in telogen at any time, a variety of factors promote anagen to telogen transition, including inflammation, hormones, stress, nutritional deficiency, poor sleep quality, and cellular division inhibiting medication. Conversely, increased blood flow, direct stimulation of the hair follicle, and growth factors promote telogen to anagen transition and subsequent hair growth. This review seeks to comprehensively describe the hair cycle, anagen and telogen balance, factors that promote anagen to telogen transition and vice versa, and the clinical utility of a variety of lab testing and evaluations. Ultimately, a variety of factors impact the hair cycle, necessitating a holistic approach to hair loss.

A practical approach to the management of hair loss in patients with polycystic ovary syndrome

Female patterned hair loss (FPHL) is a common form of androgenetic alopecia in women and is characterized by a hormonally directed diffuse hair loss on the scalp. Management of FPHL is well described in the literature; however, treatment of FPHL in patients with co-morbid polycystic ovarian syndrome (PCOS), an endocrinologic condition found in reproductive-aged women, has not yet been reviewed. Due to the different pathomechanism of the diseases and complexity of FPHL in PCOS patients, this study aimed to review current diagnosis and management approaches for hair loss in PCOS patients specifically and highlight the growing need for more research in this growing patient population.

Positioning of Low Alcohol or Alcohol-Free Minoxidil Formulation for the Management of Androgenetic Alopecia: Indian Perspective

Topical minoxidil is used for treating different hair disorders. Even though it is an effective therapy, many patients show poor compliance due to the cost, side effects, and duration of treatment. Topical minoxidil is the mainstay treatment for androgenetic alopecia (AGA). Recently, low alcohol or alcohol-free topical minoxidil formulation has proven to be an alternative for patients suffering from AGA, including those with poor compliance with other therapies. Thus, the current article provides the positioning of low alcohol or alcohol-free topical minoxidil to manage AGA in Indian clinical practice.

A cannabinoid Hairy-Tale: Hair loss or hair gain?

BACKGROUND

Few studies have reported on the use of cannabinoid products to treat hair loss.

AIM

This article aims to reconcile cannabinoids' impact on hair growth.

METHOD

A comprehensive and structured search was conducted in PubMed and Google Scholar on June 23, 2022.

RESULT

While cannabidiol (CBD), a phytocannabinoid, may cause hair growth, several other phytocannabinoids may lead to hair loss. Additionally, the effect of CBD on hair growth may be concentration-dependent. CBD may cause hair loss at high concentrations (≥10 μM). Therefore, the concentration of CBD needs to be adjusted so that it is optimal for hair growth. One trial found that once-daily application of CBD-rich topical cannabis extract for 6 months increased nonvellus hair count by approximately 93.5% in 35 Caucasian AGA patients: 28 males aged 28-72 years [average 43 years] and 7 females aged 46-76 years [average 61 years]. Each application contained 3-4 mg of CBD. The CBD-rich topical cannabis extract was prepared by ultra-pulverizing Cannabis sativa [hemp] flower into a green chalk-like powder [10.78% CBD and 0.21% tetrahydrocannabinol] and then infusing the powder into a lanolin paste and Emu oil carrier.

CONCLUSION

Topical CBD preparations require further studies to establish their safety and efficacy profile. An ideal topical cannabinoid preparation should contain CBD at the right concentration and lack other phytocannabinoid adulterants.

Hair Follicle Melanocytes Initiate Autoimmunity in Alopecia Areata: a Trigger Point

Alopecia areata (AA) is characterized by common non-scarring alopecia due to autoimmune disorders. To date, the specific pathogenesis underlying AA remains unknown. Thus, AA treatment in the dermatological clinic is still a challenge. Numerous clinical observations and experimental studies have established that melanocytes may be the trigger point that causes hair follicles to be attacked by the immune system. A possible mechanism is that the impaired melanocytes, under oxidative stress, cannot be repaired in time and causes apoptosis. Melanocyte-associated autoantigens are released and presented, inducing CD8⁺ T cell attacks. Thereafter, amplification of the immune responses further spreads to the entire hair follicle (HF). The immune privilege of HF subsequently collapses, leading to AA. Herein, we present a narrative review on the roles of melanocytes in AA pathogenesis, aiming to provide a better understanding of this disease from the melanocyte's perspective.

There Is a Positive Dose-Dependent Association between Low-Dose Oral Minoxidil and Its Efficacy for Androgenetic Alopecia: Findings from a Systematic Review with Meta-Regression Analyses

Background

Recently, low-dose oral minoxidil (LDOM) has entered the landscape of therapies for androgenetic alopecia (AGA). We determined whether using LDOM is associated with improving AGA in a dose-dependent manner; secondarily, we examined whether a dose-dependent association also exists for safety.

Methods

Systematic searches were conducted in PubMed and Scopus to identify studies that would be eligible for our quantitative analyses; the logistics of our analyses was determined by the data we gathered.

Results

Six studies were eligible for quantitative analyses; we conducted meta-regressions. We found that, for persons with AGA, increasing the dosage of LDOM by 1 mg/day was − after six months − significantly associated with an expected sex-adjusted increase in hair diameter (mean difference = 1.4 μm, p = 0.01), total hair density (mean difference = 47.1 hairs/cm², p = 0.007), terminal hair density (mean difference = 9.1 hairs/cm², p = 0.001), risk of hypertrichosis (mean difference = 17.9%, p = 0.006), and cardiovascular adverse events (mean difference = 4.8%, p = 0.004).

Conclusions

Our study produced new evidence as our work is the first to show a positive dose-dependent association between the use of LDOM and change in hair diameter, hair density, risk of hypertrichosis, and cardiovascular adverse events for persons with AGA. Future randomized trials could produce causal evidence that would corroborate these dose-dependent associations.

The effect of placebo in split-scalp and whole-head platelet-rich plasma trials for androgenetic alopecia differs: Findings from a systematic review with quantitative evidence syntheses

BACKGROUND

Some studies have shown that platelet-rich plasma (PRP) improves androgenetic alopecia (AGA)-while others do not. We determined whether the placebo effect significantly varies between split-scalp and whole-head trials on PRP monotherapy for AGA. Our rationale was based on the plausibility of PRP diffusing to the control (i.e., 'placebo') side of split-scalp trials. This is not possible in whole head studies.

METHODS

We systematically searched the literature for available data. Our choice of analyses and outcomes were determined by the available data.

RESULTS

Our endpoint was change in total hair density six months after baseline. Our regression showed that total hair density after six months was significantly (p<0.05) higher in the placebo arm of split-scalp trials, compared to whole-head studies, by 37 hairs/cm² . Our one-arm meta-analyses showed that the pooled change in total hair density between the PRP side and placebo side in split scalp studies was -3 hairs/cm² (p=0.37), that is, a slight decrease in hair density in the placebo side of the scalp. For whole head stdies the corresponding difference in total hair density between patients receiving PRP and those on placebo was -30 hairs/cm² (p=0.000017), that is, a much larger decrease in hair density. Patients in the placebo group in whole-head trials lost significantly more hair than in the placebo side of the split-head trials where hair loss was comparatively reduced-presumably because of PRP diffusing from the treatment side of the scalp.

CONCLUSIONS

The association between design (i.e., split-scalp vs. whole-head) and outcome, in placebo arms of AGA trials on PRP monotherapy, had never been reported. This 'design effect' could partly reconcile the incongruent conclusions across the PRP literature for AGA; furthermore, clinical guidelines can consider 'design effect' when selecting evidence to base care practices on.