Prostaglandin-induced hair growth

Eyelash serums: A comprehensive review

BACKGROUND

Eyelash serums, both prescription and over-the-counter, are gaining popularity for enhancing the appearance of eyelashes through various biologically active molecules. Categorized into prostaglandin analogs and non-prostaglandin analogs, these serums claim increased strength, length, luster, and thickness. Current United States law also requires no efficacy or safety assessments by the Food and Drug Administration before approving products for consumer use, potentially posing health risks for patients seeking over-the-counter eyelash enhancements.

AIMS

Our aims include exploring proposed benefits and adverse effects associated with eyelash serums, while providing evidence-based clinical recommendations on their use. We aim to contribute valuable insights to the understanding of eyelash serums and their respective safety considerations.

METHODS

The authors conducted a comprehensive electronic search across databases including PubMed, Embase, Cochrane Central, and Google Scholar to evaluate eyelash serum ingredients. Articles were evaluated by two independent researchers for relevance, and the ingredients discussed were analyzed and given clinical recommendations for eyelash serums based off the Oxford Centre for Evidence-Based Medicine.

RESULTS

Results highlight bimatoprost's efficacy, supported by numerous studies evaluating safety and adverse effects. Other prostaglandin ingredients show potential benefits, but further studies are encouraged to enhance the understanding of respective safety profiles. While non-prostaglandins ingredients show promising data, more studies are needed due to a lack of formal evidence in eyelash serum use.

CONCLUSION

As the cosmeceutical market for eyelash serums is growing, dermatologists need to be knowledgeable about evidence-based information regarding prescription and over-the-counter eyelash serum products before making recommendations to patients.

The effects of eyelash extensions on the ocular surface

PURPOSE

To investigate the effects of eyelash extensions on the ocular surface.

METHODS

This prospective study included 32 participants with eyelash extensions in both eyes. Symptoms and clinical parameters such as conjunctival vascular density, tear meniscus height (TMH), noninvasive tear break-up time, bulbar redness, meibography, lipid layer thickness, and corneal staining were assessed in the right eyes. These measurements were taken at baseline and 1 h, 1 day, 1 week, and 1 month after eyelash extensions were applied.

RESULTS

At 1 h after eyelash extensions, ocular symptoms were reported by 27 participants (84.44 %), the most common being foreign body sensation (59.38 %). However, the Ocular Surface Disease Index scores were not statistically different between baseline, 1 week, and 1 month after eyelash extension (P > 0.05). TMH increased significantly at 1 h after eyelash extensions, from 0.27 ± 0.08 mm (baseline) to 0.29 ± 0.07 mm (P = 0.02). Subsequently, TMH decreased and was the lowest at 1 week at 0.24 ± 0.08 mm. First tear break-up time and average tear break-up time decreased to the lowest at 1 week after eyelash extension, with 8.36 ± 4.6 s and 10.71 ± 4.99 s, respectively, both of which were statistically different from baseline (P < 0.05). Corneal staining score was highest at 1 h after eyelash extensions at 0.78 ± 1.34. However, there were no significant differences in the conjunctival vascular density, bulbar redness, meiboscore, or lipid layer thickness.

CONCLUSION

This study demonstrates that eyelash extensions can lead to an imbalance in ocular surface homeostasis, resulting in corneal epithelial defects and short-term decreased tear film stability.

Structural basis for ligand recognition and activation of the prostanoid receptors

Prostaglandin F2α (PGF2α) and thromboxane A2 (TXA2) are endogenous arachidonic acid metabolites, modulating diverse physiological processes including inflammation and cardiovascular homeostasis through activating PGF2α receptor (FP) and TXA2 receptor (TP). Ligands targeting FP and TP have demonstrated efficacy in treating conditions like glaucoma and cardiovascular diseases in humans, as well as reproductive-related diseases in animals. Here, we present five cryoelectron microscopy structures illustrating FP and TP in complex with Gq and bound to PGF2α (endogenous ligand), latanoprost acid (a clinical drug), and two other synthetic agonists. Combined with mutational and functional studies, these structures reveal not only structural features for the specific recognition of endogenous ligands and attainment of receptor selectivity of FP and TP but also the common mechanisms of receptor activation and Gq protein coupling. The findings may enrich our knowledge of ligand recognition and signal transduction of the prostanoid receptor family and facilitate rational ligand design toward these two receptors.

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.

Astragalus membranaceus and Cinnamomum cassia Stimulate the Hair Follicle Differentiation-Related Growth Factor by the Wnt/β-Catenin Signaling Pathway

Astragalus membranaceus and Cinnamomum cassia are used as spices and flavorful ingredients, or medicinal herbs with pharmacological effects. In this study, the hair-growth-promoting effects of the YH complex, a newly developed formula consisting of membranaceus and C. cassia, are investigated with the prediction of its molecular mechanism. The target gene of the YH complex was about 74.8% overlapped with the gene set of 'Hair growth' on the GO Biological Process database. The oral administration of the YH complex promoted hair regrowth and increased hair-shaft thickness in depilated hair loss mice. In addition, the anagen/telogen hair follicle ratio was significantly increased by the YH complex. The growth factors affecting the growth of hair follicles were dose-dependently increased by treatment with the YH complex. The Wnt/β-catenin signaling pathway expressions in skin tissues were apparently increased by the administration of the YH complex. In conclusion, the YH complex consisting of A. membranaceus and C. cassia induced hair follicle differentiation and preserved the growing-anagen phase by increasing growth factors and the Wnt/β-catenin signaling pathway, leading to the restoration of hair loss. The YH complex can be a remedy for hair loss diseases, such as alopecia areata, androgenetic alopecia, telogen effluvium, and chemotherapy-induced alopecia.

TFOS Lifestyle: Impact of cosmetics on the ocular surface

In this report the use of eye cosmetic products and procedures and how this represents a lifestyle challenge that may exacerbate or promote the development of ocular surface and adnexal disease is discussed. Multiple aspects of eye cosmetics are addressed, including their history and market value, psychological and social impacts, possible problems associated with cosmetic ingredients, products, and procedures, and regulations for eye cosmetic use. In addition, a systematic review that critically appraises randomized controlled trial evidence concerning the ocular effects of eyelash growth products is included. The findings of this systematic review highlight the evidence gaps and indicate future directions for research to focus on ocular surface outcomes associated with eyelash growth products.

Ligand-induced activation and G protein coupling of prostaglandin F2α receptor

Prostaglandin F_2α (PGF_2α), an endogenous arachidonic acid metabolite, regulates diverse physiological functions in many tissues and cell types through binding and activation of a G-protein-coupled receptor (GPCR), the PGF_2α receptor (FP), which also is the primary therapeutic target for glaucoma and several other diseases. Here, we report cryo-electron microscopy (cryo-EM) structures of the human FP bound to endogenous ligand PGF_2α and anti-glaucoma drugs LTPA and TFPA at global resolutions of 2.67 Å, 2.78 Å, and 3.14 Å. These structures reveal distinct features of FP within the lipid receptor family in terms of ligand binding selectivity, its receptor activation, and G protein coupling mechanisms, including activation in the absence of canonical PIF and ERY motifs and G_q coupling through direct interactions with receptor transmembrane helix 1 and intracellular loop 1. Together with mutagenesis and functional studies, our structures reveal mechanisms of ligand recognition, receptor activation, and G protein coupling by FP, which could facilitate rational design of FP-targeting drugs.

The efficacy of topical prostaglandin analogs for hair loss: A systematic review and meta-analysis

Background

Prostaglandin analogs have been found to have more versatile uses: treatment of open-angle glaucoma, high intraocular pressure, vitiligo, and other treatments. And prostaglandin analogs have been found to have an important role in the hair growth cycle. However, prostaglandin analogs have not been sufficiently studied for hair (including hair, eyelashes, and eyebrows) regeneration. In this study, a systematic review and meta-analysis of topical prostaglandin analogs on hair loss was performed.

Objective

The purpose of this meta-analysis is to determine the efficacy and safety of topical prostaglandin analogs for treating hair loss.

Methods

We searched PubMed, Embase, and Cochrane Library databases comprehensively. Data were pooled using Review Manager 5.4.1, and subgroup analyses were performed if necessary.

Results

There were six randomized controlled trials included in this meta-analysis. All studies compared prostaglandin analogs with placebo, and one trial consisted of two sets of data. The results showed that prostaglandin analogs could significantly improve the hair length and density (p &lt; 0.001). As far as adverse events are concerned, there was no significant difference between the experimental group and the control group.

Conclusion

In patients with hair loss, the topical prostaglandin analogs have better therapeutic efficacy and safety than placebo. However, the best dose and frequency of experimental treatment require further studies.

Surgical Results of Trabeculectomy among Groups Stratified by Prostaglandin-Associated Periorbitopathy Severity

PURPOSE

To report the role of prostaglandin-associated periorbitopathy (PAP) severity in the surgical effectiveness of trabeculectomy (LEC).

DESIGN

Retrospective observational case series.

PARTICIPANTS

A total of 139 consecutive eyes of 139 Japanese subjects (74 men, 65 women; mean age ± standard deviation, 65.7 ± 10.6 years) who underwent LEC were included. All had primary open-angle glaucoma (POAG), no history of conjunctival incisional surgery, completed all postoperative visits for 12 months, and information on the PAP severity using the Shimane University PAP Grading System (SU-PAP).

METHODS

Data were collected from a medical chart review at 2 hospitals.

MAIN OUTCOME MEASURES

Comparison of surgical success rates among groups stratified by SU-PAP grades 0 to 3 by survival curve analysis using the definitions of failure based on surgical intervention other than laser suture lysis (LSL), intraocular pressure (IOP) reduction below 20%, postoperative IOP exceeding 15 mmHg (definition A) or 12 mmHg (definition B), and a postoperative IOP below 6 mmHg.

RESULTS

Twelve months postoperatively, the success rates of grades 0, 1, 2, and 3 were 86%, 68%, 40%, and 0%, respectively, for definition A (P < 0.0001, log-rank test) and 86%, 61%, 36%, and 0%, respectively, for definition B (P < 0.0001). Interventions other than LSL (P < 0.0001, Cochran-Armitage trend test), IOP reduction less than 20% (P = 0.010), and IOP exceeding 15 mmHg (P = 0.016) or 12 mmHg (P < 0.0001) were associated with surgical failure; IOP under 6 mmHg was not (P = 0.31). The proportional hazard model for definition A showed that compared with grade 0, grade 2 (risk ratio [RR], 5.82, P = 0.0043) and grade 3 (RR, 12.2, P = 0.0003) were associated with surgical failure. For definition B, grade 1 (RR, 3.53, P = 0.040), grade 2 (RR, 6.65, P = 0.0021), and grade 3 (RR, 12.0, P = 0.0003) were associated with surgical failure. Differences in age, gender, preoperative IOP and medications, refractive error, and simultaneous cataract surgery were not associated with surgical failure in both models.

CONCLUSIONS

The preoperative presence of severe PAP worsens the 1-year success rate of LEC in patients with POAG. To retain the surgical effectiveness, treating physicians should prevent patients from progressing to severe PAP, an avoidable side effect, by switching or stopping the causative medications.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

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.

Enhancement of hair growth through stimulation of hair follicle stem cells by prostaglandin E2 collagen matrix

Prostaglandin metabolism is involved in the regulation of the periodic process of hair follicles. Preliminary research data reported that prostaglandin E2 (PGE2) exhibits potential in hair growth. However, the relevant evidence is still insufficient. Herein, we prepared a PGE2 matrix by conjugating PGE2 with collagen via crosslinkers to avoid rapid degradation of PGE2 molecules in vivo. First, we measured the physical properties of the PGE2 matrix. A mouse model of hair loss was established, and PGE2 matrix subcutaneous injection was applied to evaluate hair growth. Under different treatments with the PGE2 matrix, the morphology of hair follicles, the dynamic expression of hair follicle stem cell markers and key regulators in the hair growth cycle were explored. Our data revealed that the PGE2 matrix increased the proportion of developing hair follicles at the early growth stage. Improvements in hair follicle stem cells, such as Sox9+ and Lgr5+ cells, have also been confirmed as therapeutic effects of PGE2 to stimulate hair follicle growth. Our study indicated that PGE2 exhibits effective roles in hair development during anagen. Furthermore, the results also highlight the potential of the PGE2 delivery system as a novel therapeutic strategy for the treatment of hair disorders in the future.

Uses of eye drops in dermatology, literature review

Background: Since medication absorption through the skin and eye tissue seems similar, commercially available eye-drops could be used to treat skin diseases when topical therapies are unavailable or unaffordable. The FDA-approved and off-label applications of various eye drops used as topical treatments in dermatological clinical practice were highlighted in this review.Methodology: A thorough PubMed and Google Scholar library search using various combinations of the keywords (Eye drop, ocular solution, conjunctival installation, and skin diseases, topical, local, beta-blockers, prostaglandin, cyclosporin, apraclonidine, atropine, oxymetazoline).Results and conclusions: Based on the findings of the studies reviewed, timolol is highly recommended for infantile hemangioma and other vascular skin conditions such as angiomas, Kaposi sarcoma, acne, rosacea, and wound healing. Bimatoprost is a drug that can be used to treat hypotrichosis of any kind, as well as mild localized alopecia areata and leukoderma. Oxymetazoline ispromising for treating facial erythema. We recommend apraclonidine for mild upper eyelid ptosis induced botulinum neurotoxin. We don't recommend atropine for hyperhidrosis, although it can help with hydrocystomas and pruritis produced by syringomas. Tobramycin will need to be tested in RCTs before it can be confirmed as a viable alternative to systemic treatments for treating green nail syndrome.

Emerging drugs for the treatment of glaucoma: a review of phase II & III trials

INTRODUCTION

Glaucoma is a progressive optic neuropathy and the leading cause of irreversible vision loss. By 2040, the number of individuals with glaucoma is expected to nearly double. The only known modifiable risk factor for glaucoma is intraocular pressure. Topical medications are often used as first-line therapies. Although there are numerous available treatments, there continues to be a need for the development of new medical therapies due to variable response, intolerable side-effect profiles in some patients, and elevated intraocular pressure refractory to other treatments.

AREAS COVERED

This review will cover glaucoma medications currently undergoing phase II and III of drug development.

EXPERT OPINION

There are numerous drugs currently in development that have demonstrated significant and clinically relevant reduction of intraocular pressure. Differentiating factors include improved tolerability, novel mechanisms of action, multiple mechanisms of action, or superior IOP reduction. However, the availability of generic prostaglandin analogs may limit adoption of these novel compounds as first-line agents, except for certain subgroups of glaucoma patients. Use as adjuvant or second-line therapy appears more likely for the majority of glaucoma patients.

Nanostructured lipid carriers loaded with an association of minoxidil and latanoprost for targeted topical therapy of alopecia

Alopecia is a condition associated with different etiologies, ranging from hormonal changes to chemotherapy, that affects over 80 million people in the USA. Nevertheless, there are currently few FDA-approved drugs for topical treatment, and existing formulations still present skin irritation issues, compromising treatment adherence. This work aimed to develop a safe formulation based on nanostructured lipid carriers (NLC) that entrap an association of minoxidil and latanoprost and target drug delivery to the hair follicles. To do so, thermal techniques combined with FTIR were used to assess the chemical compatibility of the proposed drug association. Then, NLC with 393.5 ± 36.0 nm (PdI<0.4) and +22.5 ± 0.2 mV zeta potential were produced and shown to entrap 86.9% of minoxidil and 99.9% of latanoprost efficiently. In vitro, the free drug combination was indicated to exert positive effects over human primary epidermal keratinocytes, supporting cell proliferation, migration and inducing the mRNA expression of MKI67 proliferation marker and VEGF - a possible effector for minoxidil-mediated hair growth. Interestingly, such a favorable drug combination profile was optimized when delivered using our NLC. Furthermore, according to the HET-CAM and reconstructed human epidermis assays, the nanoformulation was well tolerated. Finally, drug penetration was evaluated in vitro using porcine skin. Such experiments indicated that the NLC could be deposited preferentially into the hair follicles, causing a considerable increase in the penetration of the two drugs in such structures, compared to the control (composed of the free compounds) and generating a target-effect of approximately 50% for both drugs. In summary, present results suggest that hair follicle-targeted delivery of the minoxidil and latanoprost combination is a promising alternative to treat alopecia.

Prostaglandin-associated periorbitopathy syndrome (PAPS): Addressing an unmet clinical need

BACKGROUND

Topical prostaglandin analogs (PGAs) are widely approved and preferred first-line options for glaucoma and elevated intraocular pressure (IOP). However, prostaglandin-associated periorbitopathy syndrome (PAPS) is now a well-recognized clinical and cosmetic concern for patients receiving PGAs, especially during long-term and unilateral therapy. PGA-associated periocular changes occur in a substantial proportion of patients, with older patients (>60 years) at greater risk of clinical presentation. PAPS may hinder long-term management of glaucoma, including treatment adherence, ophthalmic surgery outcomes, and reliable IOP measurements.

RECOMMENDATION

New therapeutic approaches may address this unmet clinical need. Omidenepag isopropyl (OMDI) is a novel, non-prostaglandin, selective EP₂ receptor agonist in ongoing development, which provides a unique pharmacological mechanism of action. OMDI appears to provide IOP reductions comparable to PGAs, but without PAPS-related undesirable effects. OMDI may offer a suitable long-term option for patients who demonstrate decreased efficacy, or failure, of PGAs, plus patients with significant PAPS, while fulfilling international guidelines.

Treatment options for androgenetic alopecia: Efficacy, side effects, compliance, financial considerations, and ethics

Background

Androgenetic alopecia (AGA) is the most common form of hair loss consisting of a characteristic receding frontal hairline in men and diffuse hair thinning in women, with frontal hairline retention, and can impact an individual's quality of life. The condition is primarily mediated by 5‐alpha‐reductase and dihydrotestosterone (DHT) which causes hair follicles to undergo miniaturization and shortening of successive anagen cycles. Although a variety of medical, surgical, light‐based and nutraceutical treatment options are available to slow or reverse the progression of AGA, it can be challenging to select appropriate therapies for this chronic condition.

Aims

To highlight treatment options for androgenetic alopecia taking into consideration the efficacy, side effect profiles, practicality of treatment (compliance), and costs to help clinicians offer ethically appropriate treatment regimens to their patients.

Materials and Methods

A literature search was conducted using electronic databases (Medline, PubMed, Embase, CINAHL, EBSCO) and textbooks, in addition to the authors' and other practitioners' clinical experiences in treating androgenetic alopecia, and the findings are presented here.

Results

Although topical minoxidil, oral finasteride, and low‐level light therapy are the only FDA‐approved therapies to treat AGA, they are just a fraction of the treatment options available, including other oral and topical modalities, hormonal therapies, nutraceuticals, PRP and exosome treatments, and hair transplantation.

Discussion

Androgenetic alopecia therapy remains challenging as treatment selection involves ethical, evidence‐based decision‐making and consideration of each individual patient's needs, compliance, budget, extent of hair loss, and aesthetic goals, independent of potential financial benefits to the practitioners.

Setipiprant for Androgenetic Alopecia in Males: Results from a Randomized, Double-Blind, Placebo-Controlled Phase 2a Trial

Purpose

To evaluate oral setipiprant versus placebo for scalp hair growth in men with androgenetic alopecia (AGA).

Patients and Methods

Males aged 18 to 49 years with AGA were enrolled in a double-blind, multicenter, 32-week, phase 2a trial; randomized to twice-daily (BID) 1000-mg (2×500 mg for a total daily dose of 2000 mg) setipiprant tablets or placebo for 24 weeks; and assessed at weeks 4, 8, 16, and 24, with a week 32 follow-up. The study initially included a finasteride 1-mg once-daily group, removed by protocol amendment. Changes from baseline to week 24 in target area hair count (TAHC) and blinded Subject Self-Assessment (SSA) of target area photographs were coprimary efficacy endpoints. Hair growth was also evaluated using blinded Investigator Global Assessment (IGA). Safety assessments included adverse events (AEs) and clinical laboratory tests. Analysis of covariance models were used to test statistical significance for TAHC, SSA, and IGA. Data were summarized without statistical analysis for finasteride.

Results

Randomized subjects (N=169) included 74 placebo, 83 setipiprant, and 12 finasteride subjects; 117 (69.2%) and 113 (66.9%) subjects completed week 24 and 32 visits, respectively. Treatment groups had similar baseline characteristics. Neither coprimary efficacy endpoint was met. At week 24, TAHC and SSA findings indicated no hair growth improvements with setipiprant versus placebo. Setipiprant also did not improve hair growth versus placebo per the IGA. Treatment-related AEs, all mild or moderate in severity, occurred in 12.3%, 25.9%, and 25.0% of the placebo, setipiprant, and finasteride groups, respectively. Two treatment-emergent serious AEs (TESAEs), cellulitis and multiple sclerosis, were reported in the placebo group, both unrelated to treatment. No TESAEs were reported with setipiprant or finasteride.

Conclusion

Setipiprant 1000 mg BID was safe and well tolerated but did not demonstrate efficacy versus placebo for scalp hair growth in men with AGA.

Revisiting the Safety of Prostaglandin Analog Eyelash Growth Products

BACKGROUND

The FDA approved bimatoprost ophthalmic solution 0.03% for treatment of eyelash hypotrichosis in 2008. Consumer concern persists regarding potential side effects of this product.

OBJECTIVE

To identify gaps in the safety information associated with the use of prostaglandin eyelash growth products.

MATERIALS AND METHODS

Literature searches were performed using PubMed, Embase, and Nexis Uni databases without restriction to publication date, language, or study setting.

RESULTS

The literature pertaining to bimatoprost for treatment of eyelash hypotrichosis is dominated by industry-sponsored clinical trials. Study design choices create gaps in our understanding of the clinical safety of these products.

CONCLUSION

Because of study design choice, clinical trials of bimatoprost for eyelash growth may have systematically underreported the incidence of drug application discomfort and prostaglandin-associated periorbitopathy. The risk of increased iris pigmentation remains inadequately investigated. Consequently, there is an ongoing need to educate and monitor patients who choose to use these products.

Proposal of a simple grading system integrating cosmetic and tonometric aspects of prostaglandin-associated periorbitopathy

The distribution of prostaglandin-associated periorbitopathy (PAP) graded using the Shimane University PAP Grading System (SU-PAP) among glaucoma/ocular hypertension subjects using a topical FP or EP2 receptor agonist was reported. A 460 consecutive 460 Japanese subjects (211 men, 249 women; mean age ± standard deviation, 69.9 ± 14.5 years) who had used either a FP agonist (0.005% latanoprost, 0.0015% tafluprost, 0.004% travoprost, 0.03% bimatoprost, or fixed combinations of these) or EP2-agonist (0.002% omidenepag isopropyl) for more than 3 months in at least 1 eye were retrospectively enrolled. Age, sex, prostaglandin, intraocular pressure (IOP) measured by Goldmann applanation tonometry (IOPGAT) and iCare rebound tonometry (IOPRBT), difference between IOPGAT and IOPRBT (IOPGAT-RBT), PAP grade, and PAP grading items were compared among groups stratified by PAP grade or prostaglandins. Of the study patients, 114 (25%) had grade 0 (no PAP), 174 (38%) grade 1 (superficial cosmetic PAP), 141 (31%) grade 2 (deep cosmetic PAP), and 31 (7%) grade 3 (tonometric PAP). The IOPGAT was significantly higher in grade 3 (17.5 ± 5.4 mm Hg) than grades 0 (15.0 ± 5.1 mm Hg, P = .032) and 1 (14.5 ± 4.2 mm Hg, P = .008), and the IOPGAT-RBT was significantly higher in grade 3 (5.8 ± 3.2 mm Hg) than the other 3 grades (1.3-1.9 mm Hg, P < .001 for all comparisons); the IOPRBT was equivalent among the 4 grades. The PAP grade was significantly higher associated with travoprost (2.0 ± 0.8) and bimatoprost (2.0 ± 0.7) than latanoprost (1.0 ± 0.8, P < .001 for both comparisons) and tafluprost (1.0 ± 0.7, P < .001 for both comparisons), but significantly lower associated with omidenepag (0.0 ± 0.0, P < .001 for all comparisons) than the other 4 prostaglandins. Multivariate analyses showed older age (standard β = 0.11), travoprost (0.53, referenced by latanoprost) and bimatoprost (0.65) were associated with higher PAP grades, while tafluprost (-0.18) and omidenepag (-0.73) were associated with lower PAP grades. The PAP graded using SU-PAP reflects the degree of overestimation of the IOPGAT and different severities of PAP among the different prostaglandins. SU-PAP, the grade system constructed based on the underlining mechanisms of PAP, is a simple grading system for PAP that is feasible for use in a real-world clinical situation.

Complications and Adverse Effects of Periocular Aesthetic Treatments

The popularity and variety of temporary and permanent periocular aesthetic treatments has increased over the past decade. Patients frequently present to eye clinics with ocular complications and side effects following these treatments, their severity ranging from ocular irritation from dry eyes to visual loss from vascular occlusion. A careful, thorough history is essential, as many patients may not associate aesthetic procedures with ocular complications, and some may be embarrassed to disclose this information. All ophthalmologists should understand the potential ocular sequelae of these treatments and be able to initiate treatment in sight-threatening cases. Wesummarises the current literature on ophthalmic complications of the most common periocular aesthetic treatments.

Therapeutic potential of castor oil in managing blepharitis, meibomian gland dysfunction and dry eye

The multifactorial pathogenesis and interrelationship of blepharitis, meibomian gland dysfunction and dry eye disease poses challenges to any therapeutic approach. Current treatments are mostly palliative, with success limited by perceived inefficacy and poor patient compliance. Castor oil, a natural derivative of the Ricinus communis plant, is widely used as an emollient in cosmetics and personal care products, drug delivery systems and wound dressings. Castor oil is deemed safe and tolerable, with strong anti-microbial, anti-inflammatory, anti-nociceptive, analgesic, antioxidant, wound healing and vaso-constrictive properties. Its main constituent, ricinoleic acid, has a bipolar molecular structure that promotes the formation of esters, amides and polymers. These can supplement deficient physiological tear film lipids, enabling enhanced lipid spreading characteristics and reducing aqueous tear evaporation. Studies reveal that castor oil applied topically to the ocular surface has a prolonged residence time, facilitating increased tear film lipid layer thickness, stability, improved ocular surface staining and symptoms. This review summarises the properties, current uses of, and therapeutic potential of castor oil in managing ocular surface disease. The biochemical, medicinal actions of castor oil are explored from the perspective of ocular surface pathology, and include microbial and demodectic over-colonisation, inflammatory and oxidative processes, as well as clinical signs and symptoms of dryness and discomfort.

Whole genome sequencing identified a 16 kilobase deletion on ECA13 associated with distichiasis in Friesian horses

BACKGROUND

Distichiasis, an ocular disorder in which aberrant cilia (eyelashes) grow from the opening of the Meibomian glands of the eyelid, has been reported in Friesian horses. These misplaced cilia can cause discomfort, chronic keratitis, and corneal ulceration, potentially impacting vision due to corneal fibrosis, or, if secondary infection occurs, may lead to loss of the eye. Friesian horses represent the vast majority of reported cases of equine distichiasis, and as the breed is known to be affected with inherited monogenic disorders, this condition was hypothesized to be a simply inherited Mendelian trait.

RESULTS

A genome wide association study (GWAS) was performed using the Axiom 670 k Equine Genotyping array (MNEc670k) utilizing 14 cases and 38 controls phenotyped for distichiasis. An additive single locus mixed linear model (EMMAX) approach identified a 1.83 Mb locus on ECA5 and a 1.34 Mb locus on ECA13 that reached genome-wide significance (pcorrected = 0.016 and 0.032, respectively). Only the locus on ECA13 withstood replication testing (p = 1.6 × 10- 5, cases: n = 5 and controls: n = 37). A 371 kb run of homozygosity (ROH) on ECA13 was found in 13 of the 14 cases, providing evidence for a recessive mode of inheritance. Haplotype analysis (hapQTL) narrowed the region of association on ECA13 to 163 kb. Whole-genome sequencing data from 3 cases and 2 controls identified a 16 kb deletion within the ECA13 associated haplotype (ECA13:g.178714_195130del). Functional annotation data supports a tissue-specific regulatory role of this locus. This deletion was associated with distichiasis, as 18 of the 19 cases were homozygous (p = 4.8 × 10- 13). Genotyping the deletion in 955 horses from 54 different breeds identified the deletion in only 11 non-Friesians, all of which were carriers, suggesting that this could be causal for this Friesian disorder.

CONCLUSIONS

This study identified a 16 kb deletion on ECA13 in an intergenic region that was associated with distichiasis in Friesian horses. Further functional analysis in relevant tissues from cases and controls will help to clarify the precise role of this deletion in normal and abnormal eyelash development and investigate the hypothesis of incomplete penetrance.

The Antiglaucoma Agent and EP2 Receptor Agonist Omidenepag Does Not Affect Eyelash Growth in Mice

Purpose: The present study investigated the effects of the antiglaucoma agent and selective E2 receptor agonist omidenepag isopropyl (OMDI) on eyelash growth in comparison with a prostaglandin analog (prostamide receptor agonist) in mice.

Methods: Four-week-old female mice (C57BL/6J) were divided into 3 groups of n = 10 each. The groups were administered 3 μL of 0.003% OMDI solution, the vehicle (negative control), or a 0.03% bimatoprost solution (positive control) on the upper eyelids of the right eyes once daily for 14 days. On the 15th day, all animals were euthanized, and the upper eyelids with eyelashes were fixed with 10% neutral formalin. Eyelashes were evaluated for number, length, and thickness using a stereomicroscope. Specimens were then paraffin-embedded and stained with hematoxylin and eosin, followed by microscopic examination to assess eyelash morphology and growth cycle.

Results: Eyelash number (143.5 ± 6.7/eyelid), thickness, and percentage of dermal papilla in the anagen phase in the OMDI group were similar to those observed in the vehicle group (eyelash number, 144.2 ± 5.7/eyelid). In contrast, eyelash number (166.7 ± 7.0/eyelid), thickness, and the percentage of dermal papilla in the anagen phase were significantly greater in the bimatoprost group compared with those of the vehicle group.

Conclusions: Unlike existing prostaglandin analogs, our findings indicate that OMDI has no effect on eyelash growth in mice, suggesting that it may be a promising antiglaucoma agent with a reduced number of adverse effects.

A review of the treatment of male pattern hair loss

Introduction: Androgenetic alopecia is a common hair loss disorder affecting up to 80% of males by the age of 80. It is characterized by androgen related progressive thinning of hair in a defined pattern. It results in diminished self-esteem, reduced confidence and distress in affected men, irrespective of age or stage of baldness. An effective treatment for hair baldness is needed.Areas covered: In androgenetic alopecia, hair follicles undergo progressive miniaturization. Genetic factors and androgens are key role-players in disease pathogenesis. Herein the authors review the pharmacologic treatment of androgenetic alopecia, which involves 5 alpha reductase inhibitors, minoxidil and prostaglandins. Non-pharmacologic approaches are also explored.Expert opinion: Androgenetic alopecia progresses over time and although the current available medical treatments like finasteride and minoxidil are effective in arresting the progression of the disease, they allow only partial regrowth of hair at its best. Early treatment achieves a more optimal outcome. Non-pharmacologic treatments like PRP can be considered in patients refractory to medical treatment.Abbreviations: MPHL: male pattern hair loss; AGA: androgenetic alopecia; DHT: dihydrotestosterone; 5AR: 5-alpha-reductase; VEGF: vascular endothelial growth factor; PG's: prostaglandins (PG's); PGD2R: prostaglandin D2 receptor; VPA: valproic aid; SR: Serenoa Repens; PRP: platelet-rich plasma; PDGF: platelet derived growth factor; TGF: transforming growth factor; ERK: extracellular signal-regulated kinase; PKB: protein kinase B; LLLT: low-level laser therapy; ROS: reactive oxygen species; RCT: randomized control trial; SFRP1: secreted frizzled related protein 1; DP: dermal papilla; PDE5: phosphodiesterase 5.

Kinetics of Fluorescein in Tear Film After Eye Drop Instillation in Beagle Dogs: Does Size Really Matter?

The study aimed to determine the impact of drop size on tear film pharmacokinetics and assess important physiological parameters associated with ocular drug delivery in dogs. Two separate experiments were conducted in eight healthy Beagle dogs: (i) Instillation of one drop (35 μl) or two drops (70 μl) of 1% fluorescein solution in each eye followed by tear collections with capillary tubes from 0 to 180 min; (ii) Instillation of 10 to 100 μl of 0.1% fluorescein in each eye followed by external photography with blue excitation filter (to capture periocular spillage of fluorescein) and tear collections from 1 to 20 min (to capture tear turnover rate; TTR). Fluorescein concentrations were measured in tear samples with a fluorophotometer. The TTR was estimated based upon non-linear mixed-effects analysis of fluorescein decay curves. Tear film pharmacokinetics were not superior with instillation of two drops vs. one drop based on tear film concentrations, residual tear fluorescence, and area under the fluorescein-time curves (P ≥ 0.163). Reflex TTR varied from 20.2 to 30.5%/min and did not differ significantly (P = 0.935) among volumes instilled (10-100 μl). The volumetric capacity of the canine palpebral fissure (31.3 ± 8.9 μl) was positively correlated with the palpebral fissure length (P = 0.023). Excess solution was spilled over the periocular skin in a volume-dependent manner, predominantly in the lower eyelid, medial canthus and lateral canthus. In sum, a single drop is sufficient for topical administration in dogs. Any excess is lost predominantly by spillage over the periocular skin as well as accelerated nasolacrimal drainage.

Analysis of Bimatoprost-Induced changes on Rabbits eyelash Follicle: Clinical and Electron microscopic study

Objective

To analyze ultrastructural changes of rabbits' eyelash follicles treated with bimatoprost eye drops to increase our knowledge of how this drug works.

Methods

The study included 15 clinically healthy male rabbits. All rabbits were treated with bimatoprost 0.03% daily for 4 weeks with one drop of the topical eye drops applied to the conjunctival fornix of the right eyes; left eyes were used as controls. Eyelash lengths were measured before and after treatment. The eyelid of each animal was dissected for light and electron microscopic analysis.

Results

Both control and treated rabbit eyes matched regarding eyelash length before treatment (9.80±0.388mm vs 9.88±0.24mm) (P=0.108). There was a significant increase in eyelash length between control (9.75±0.33 mm) and treated rabbit eyes (11.60±0.46 mm) (P=0.369). Light and electron microscopy revealed, bimatoprost treated eyes had thick epidermis. The dermis contained two hairs growing out of the same hair follicle. Heavily keratinized Henle's layer, the cortical cells (Cx) have prominent nucleolus and cytoplasm is studded with melanin granules.

Conclusion

Bimatoprost-induced eyelash changes were not restricted to increased eyelash length, thickness, and pigmentation but also showed increased number of eyelashes within the same hair follicle which were stronger and could resist pulling from the skin without any evidence of inflammatory cells within the specimens. These changes occurred as early as 1 month of treatment, giving rise to thoughts about the possibility of using bimatoprost eye drops as a prophylaxis against madarosis associated with chemotherapy if it is started 1 month before chemotherapy and continued afterwards, making eyelashes stronger and resistant to falling out.

How eyelashes can protect the eye through inhibiting ocular water evaporation: a chemical engineering perspective

Bionics is a fascinating subject that has inspired many inventions through learning from biological structures and functions. In this work, a coupled multi-physics model has been developed to characterize ocular water evaporation with realistic eyelash structures taken into account. From a chemical engineering perspective, the protective function of human eyelashes in terms of evaporation inhibition has been rationally revealed. Systematic investigations were carried out to elucidate the effects of different eyelash lengths, orientations and inlet air directions on water evaporation on the ocular surface. The results clearly demonstrate that regardless of inlet air directions and eyelash orientations, increasing eyelash length from zero to an optimal length can effectively reduce water evaporation. However, further increase in the eyelash length can lead to enhanced evaporation. For the normal and parallel inlet air directions, the optimal eyelash length is around 15-30% of the eye width and can offer approximately 10-30% evaporation reduction when compared with the cases without eyelashes. These values are independent of the eyelash orientation. This investigation provides valuable data for in-depth understanding of the protective function of the eyelashes, which can be used in the future to improve and optimize bionic designs inspired by human eyelashes.

Hair Growth Promoting Effect of 4HGF Encapsulated with PGA Nanoparticles (PGA-4HGF) by β-Catenin Activation and Its Related Cell Cycle Molecules

Poly-γ-glutamic acid (γ-PGA)-based nanoparticles draw remarkable attention as drug delivery agents due to their controlled release characteristics, low toxicity, and biocompatibility. 4HGF is an herbal mixture of Phellinus linteus grown on germinated brown rice, Cordyceps militaris grown on germinated soybeans, Polygonum multiflorum, Ficus carica, and Cocos nucifera oil. Here, we encapsulated 4HGF within PGA-based hydrogel nanoparticles, prepared by simple ionic gelation with chitosan, to facilitate its penetration into hair follicles (HFs). In this study, we report the hair promoting activity of 4HGF encapsulated with PGA nanoparticles (PGA-4HGF) and their mechanism, compared to 4HGF alone. The average size of spherical nanoparticles was ~400 nm in diameter. Continuous release of PGA-4HGF was observed in a simulated physiological condition. As expected, PGA-4HGF treatment increased hair length, induced earlier anagen initiation, and elongated the duration of the anagen phase in C57BL/6N mice, compared with free 4HGF treatment. PGA-4HGF significantly increased dermal papilla cell proliferation and induced cell cycle progression. PGA-4HGF also significantly increased the total amount of β-catenin protein expression, a stimulator of the anagen phase, through induction of cyclinD1 and CDK4 protein levels, compared to free 4HGF treatment. Our findings underscore the potential of PGA nanocapsules to efficiently deliver 4HGF into HFs, hence promoting hair-growth. Therefore, PGA-4HGF nanoparticles may be promising therapeutic agents for hair growth disorders.

HMGB1 promotes hair growth via the modulation of prostaglandin metabolism

Unexpected hair growth can occur after tissue injury. The pathogenic mechanism for this phenomenon is unknown but is likely related to inflammatory mediators. One such mediator is high-mobility group box 1 (HMGB1), a ubiquitous nuclear protein that is released from cell nuclei after tissue damage. To elucidate the effect of HMGB1 on hair growth and understand its mechanism of action, we evaluated the effect of HMGB1 treatment on hair shaft elongation and on mRNA and protein expression in cultured human dermal papilla cells (hDPCs). HMGB1 enhanced hair shaft elongation in an ex vivo hair organ culture. In hDPCs, HMGB1 treatment significantly increased mRNA and protein expression levels of prostagladin E synthases. HMGB1 also stimulated prostaglandin E2 (PGE₂) secretion from hDPCs. Finally, blocking the receptor for advanced glycation end-products, a canonical HMGB1 receptor, inhibited HMGB1-induced PGE₂ production and hair shaft elongation. Our results suggest that HMGB1 promotes hair growth via PGE₂ secretion from hDPCs. This mechanism can explain the paradoxical phenomenon of trauma-induced hair growth. Thus, HGMB1 can be a viable therapeutic target for the treatment of alopecia.

Current management of glaucoma

Glaucoma is an irreversible progressive optic neuropathy, for which the major proven treatment is to lower the intraocular pressure (IOP). Five groups of IOP-lowering eye drops have varying mechanisms of action. Some drops, such as β-blockers and α-2 agonists, have potentially serious systemic side effects. Acetazolamide is the only available oral agent; it is effective at lowering IOP, but significant side effects relegate its use usually to refractory glaucoma. Two new eye drops, netarsudil and latanoprostene bunod, have recently been approved by the United States Food and Drug Administration. Both have novel IOP-lowering mechanisms and target the conventional aqueous outflow system. Selective laser trabeculoplasty is a gentle treatment that enhances conventional aqueous outflow. It may be used as an initial treatment, as a substitute for eye drops, or to delay glaucoma drainage surgery. Recent advancements in glaucoma surgery have seen an influx of minimally invasive glaucoma surgery devices, which are being used more frequently and earlier on in the treatment paradigm. As limited long term data are available, trabeculectomy remains the gold standard IOP-lowering procedure. Improvements in drug delivery are on the horizon. Drug-eluting devices and implants are able to deliver the drug closer to the receptors for an extended period of time. This will improve treatment adherence and efficacy, which are major limitations with current medical therapy.

Efficacy of Off-Label Topical Treatments for the Management of Androgenetic Alopecia: A Review

Androgenetic alopecia (AGA) is characterized by non-scarring follicle miniaturization. Despite the success of approved therapies, commonly reported side effects and the need for continual use has led to the investigation of alternative therapies. The aim of this paper is to critically review the success of off-label, topical monotherapies for treatment of AGA in men. A literature search was conducted to obtain randomized, controlled and blinded studies that investigated off-label, topical, monotherapies in male patients. Hair density, hair diameter and hair growth were used to evaluate treatment success. Fourteen off-label topical therapies were investigated among the 16 studies that met inclusion criteria. Nine off-label therapies were reported to produce a significantly greater improvement in hair restoration parameters (e.g. mean change from hair count and hair diameter) as compared to placebo (p < 0.05 for all treatments). In two studies, procyanidin oligomers exhibited greater efficacy over vehicle with response to mean change in hair density (hairs/cm²) (p_s < 0.0001 at Week 24). In conclusion, prostaglandin analogs and polyphenols, such as latanoprost and procyanidin oligomers, can improve hair restoration parameters in male AGA patients, possibly through targeting mechanisms proposed in the etiology of AGA. The current evidence suggests short-term (24 weeks) use may provide benefit for hair loss patients; however, long-term efficacy and safety data are required.

[Latanoprost in hypotensive therapy of glaucoma]

The review presents an analysis of therapeutic effectiveness, safety and pharmacokinetics of latanoprost - the reference representative of the prostaglandin group, summarizes the experience of its clinical use in glaucoma as monotherapy and in combination with antihypertensive drugs of other pharmacological groups, its possible effect on the inflammatory process in the anterior segment of the eye, as well as its probable participation in the development of macular edema. The article also gives a recount of relevant local and systemic adverse events.

Effects of sustained daily latanoprost application on anterior chamber anatomy and physiology in mice

Latanoprost is a common glaucoma medication. Here, we study longitudinal effects of sustained latanoprost treatment on intraocular pressure (IOP) in C57BL/6J mice, as well as two potential side-effects, changes in iris pigmentation and central corneal thickness (CCT). Male C57BL/6J mice were treated daily for 16 weeks with latanoprost. Control mice were treated on the same schedule with the preservative used with latanoprost, benzalkonium chloride (BAK), or handled, without ocular treatments. IOP and CCT were studied at pre-treatment, 2 "early" time points, and 2 "late" time points; slit-lamp analysis performed at a late time point; and expression of corneal and iridial candidate genes analyzed at the end of the experiment. Latanoprost lowered IOP short, but not long-term. Sustained application of BAK consistently resulted in significant corneal thinning, whereas sustained treatment with latanoprost resulted in smaller and less consistent changes. Neither treatment affected iris pigmentation, corneal matrix metalloprotease expression or iridial pigment-related genes expression. In summary, latanoprost initially lowered IOP in C57BL/6J mice, but became less effective with sustained treatment, likely due to physiological adaptation. These results identify a new resource for studying changes in responsiveness associated with long-term treatment with latanoprost and highlight detrimental effects of commonly used preservative BAK.

Bimatoprost in Dermatology

Bimatoprost is a prostamide analogue used for treatment of glaucoma in ophthalmology. Surprisingly, the side effects such as increased pigmentation of eyelids and hypertrichosis in patients being treated with prostaglandin analogues for glaucoma have opened new areas of application in various dermatological disorders such as alopecia mainly affecting eyelashes, eyebrows, and vitiligo.

The Comparison of Eyelash Lengthening Effect of Latanoprost Therapy in Adults and Children

PURPOSE

To compare the eyelash lengthening effect of latanoprost in adults and children with glaucoma.

METHODS

Twenty eyes of 13 men and 7 women (mean age: 54.9, range 42-69 years) with primary open-angle glaucoma and 20 eyes of 9 boys and 11 girls (mean age: 10.7, range 6-16 years) with glaucoma were included in this prospective study. In 19 children, juvenile glaucoma and in one, pseudophakic glaucoma had been detected. A single eyelash was pulled from the center of the upper eyelid before latanoprost therapy and at the sixth month of therapy, and measured.

RESULTS

In adult cases, the mean eyelash length was 5.79+/-0.18 mm (5.5-6.1 mm) at baseline and 6.45+/-0.21 mm (6.2-6.8 mm) at the sixth month. In children, the mean length was 5.66+/-0.22 mm (5.3-6.0 mm) at baseline and 6.39+/-0.37 mm (5.9-6.9 mm) at the sixth month. The mean difference in eyelash lengths at baseline and the sixth month was 0.67+/-0.09 mm (0.5-0.7 mm) in adults and 0.75+/-0.25 mm (0.4-1.2 mm) in children.

CONCLUSIONS

The differences in mean eyelash lengths at baseline and at the sixth month of latanoprost therapy were statistically significant in both adults and children (p=0.000). The mean of the difference of the eyelash length in children was higher than in adults but the result was not statistically significant (p=0.678).

TFOS DEWS II iatrogenic report

Dry eye can be caused by a variety of iatrogenic interventions. The increasing number of patients looking for eye care or cosmetic procedures involving the eyes, together with a better understanding of the pathophysiological mechanisms of dry eye disease (DED), have led to the need for a specific report about iatrogenic dry eye within the TFOS DEWS II. Topical medications can cause DED due to their allergic, toxic and immuno-inflammatory effects on the ocular surface. Preservatives, such as benzalkonium chloride, may further aggravate DED. A variety of systemic drugs can also induce DED secondary to multiple mechanisms. Moreover, the use of contact lens induces or is associated with DED. However, one of the most emblematic situations is DED caused by surgical procedures such as corneal refractive surgery as in laser-assisted in situ keratomileusis (LASIK) and keratoplasty due to mechanisms intrinsic to the procedure (i.e. corneal nerve cutting) or even by the use of postoperative topical drugs. Cataract surgery, lid surgeries, botulinum toxin application and cosmetic procedures are also considered risk factors to iatrogenic DED, which can cause patient dissatisfaction, visual disturbance and poor surgical outcomes. This report also presents future directions to address iatrogenic DED, including the need for more in-depth epidemiological studies about the risk factors, development of less toxic medications and preservatives, as well as new techniques for less invasive eye surgeries. Novel research into detection of early dry eye prior to surgeries, efforts to establish appropriate therapeutics and a greater attempt to regulate and oversee medications, preservatives and procedures should be considered.

Efficacy of topical latanoprost versus minoxidil and betamethasone valerate on the treatment of alopecia areata

BACKGROUND

Alopecia areata (AA) is one of the most common causes of localized hair loss. There is no universally proven therapy that induces and sustains remission of hair growth in AA.

OBJECTIVE

To compare the efficacy and safety of topical latanoprost, minoxidil and betamethasone valerate on hair growth in patients with AA.

PATIENTS AND METHODS

Hundred patients with AA classified into five groups of 20 treated with: Group I, latanoprost 0.1% lotion; Group II, minoxidil 5% lotion; Group III, betamethasone valerate 0.1% solution; Group IV, combination of latanoprost lotion and betamethasone valerate solution and Group V, a vehicle lotion control group.

RESULTS

There was a statistically significant improvement in all therapeutic groups when compared with control group and reduction of severity of alopecia tool score of scalp and beard before and after treatment for all therapeutic groups.

CONCLUSION

Latanoprost, minoxidil and betamethasone valerate are effective and safe in the treatment of patchy AA. The use of latanoprost added to the therapeutic efficacy of topical betamethasone valerate in the treatment of AA and could be an effective adjunctive topical therapy for AA.

Identification of genes and proteins associated with anagen wool growth

Identifying genes of major effect for wool growth would offer strategies for improving the quality and increasing the yield of fine wool. In this study, we employed the Agilent Sheep Gene Expression Microarray and proteomic technology to investigate the gene expression patterns of body side skin (more wool growing) in Aohan fine wool sheep (a Chinese indigenous breed) in comparison with groin skin (no wool growing) at the anagen stage of the wool follicle. A microarray study revealed that 4772 probes were differentially expressed, including 2071 upregulated and 2701 downregulated probes, in the comparisons of body side skin vs. groin skin (S/G). The microarray results were verified by means of quantitative PCR. A total of 1099 probes were assigned to unique genes/transcripts. The number of distinct genes/transcripts (annotated) was 926, of which 352 were upregulated and 574 were downregulated. In S/G, 13 genes were upregulated by more than 10 fold, whereas 60 genes were downregulated by more than 10 fold. Further analysis revealed that the majority of the genes possibly related to the wool growth could be assigned to categories including regulation of cell division, intermediate filament, cytoskeletal part and growth factor activity. Several potential gene families may participate in hair growth regulation, including fibroblast growth factors, transforming growth factor-β, WNTs, insulin-like growth factor, vascular endothelial growth factors and so on. Proteomic analysis also revealed 196 differentially expressed protein points, of which 121 were identified as single protein points.

Multi-therapies in androgenetic alopecia: review and clinical experiences

Androgenetic alopecia (AGA) is a genetically determined progressive hair-loss condition which represents the most common cause of hair loss in men. The use of the medical term androgenetic alopecia reflects current knowledge about the important role of androgens and genetic factors in its etiology. In addition to androgen-dependent changes in the hair cycle, sustained microscopic follicular inflammation contributes to its onset. Furthermore, Prostaglandins have been demonstrated to have the ability in modulating hair follicle cycle; in particular, PGD2 inhibits hair growth while PGE2/F2a promote growth. Due to the progressive nature of AGA, the treatment should be started early and continued indefinitely, since the benefit will not be maintained upon ceasing therapy. To date, only two therapeutic agents have been approved by the Food and Drug Administration and European Medicines Agency for the treatment of AGA: topical minoxidil and oral finasteride. Considering the many pathogenetic mechanisms involved in AGA, various treatment options are available: topical and systemic drugs may be used and the choice depends on various factors including grading of AGA, patients' pathological conditions, practicability, costs and risks. So, the treatment for AGA should be based on personalized therapy and targeted at the different pathophysiological aspects of AGA.

The Effects of Negative Pressure by External Tissue Expansion Device on Epithelial Cell Proliferation, Neo-Vascularization and Hair Growth in a Porcine Model

While pre-treating a fat transplant recipient site with negative pressure has shown promise for increasing the fat survival rate, the underlying mechanisms have not been investigated, partly due to challenges related to immobilization of vacuum domes on large animal subjects. The aim of this study was to examine the effect of negative pressure treatment by External Tissue Expansion Device (ETED) on fat grating recipient sites in a porcine model. The ETED was designed to provide negative pressure on the dorsum of swine. Pressure treatment (-70 mmHg) was applied for 1 or 3 hours every other day for 10 and 20 treatments. The treated areas (3.5 cm in diameter) were harvested and examined for histological changes, vessel density, cell proliferation (Ki67) and growth factor expression (FGF-1, VEGF and PDGB-bb). The application of the ETED increased epidermis thickness even after 1-hour treatments repeated 10 times. The results of Ki67 analysis suggested that the increasing thickness was due to cell proliferation in the epidermis. There was a more than two-fold increase in the vessel density, indicating that the ETED promotes vascularization. Unexpectedly, the treatment also increased the number of hair follicles. Negative pressure provided by the ETED increases the thickness of epidermis section of tissue, cell proliferation and vessel density. The porcine model provides a better representation of the effect of the ETED on skin tissue compared to small animal models and provides an environment for studying the mechanisms underlying the clinical benefits of negative pressure treatment.

The Modulatable Stem Cell Niche: Tissue Interactions during Hair and Feather Follicle Regeneration

Hair and feathers are unique because (1) their stem cells are contained within a follicle structure, (2) they undergo cyclic regeneration repetitively throughout life, (3) regeneration occurs physiologically in healthy individuals and (4) regeneration is also induced in response to injury. Precise control of this cyclic regeneration process is essential for maintaining the homeostasis of living organisms. While stem cells are regulated by the intra-follicle-adjacent micro-environmental niche, this niche is also modulated dynamically by extra-follicular macro-environmental signals, allowing stem cells to adapt to a larger changing environment and physiological needs. Here we review several examples of macro-environments that communicate with the follicles: intradermal adipose tissue, innate immune system, sex hormones, aging, circadian rhythm and seasonal rhythms. Related diseases are also discussed. Unveiling the mechanisms of how stem cell niches are modulated provides clues for regenerative medicine. Given that stem cells are hard to manipulate, focusing translational therapeutic applications at the environments appears to be a more practical approach.