Keratin (Hair)

1. J Dermatolog Treat. 2026 Dec;37(1):2654112. doi: 10.1080/09546634.2026.2654112. Epub 2026 Apr 30. Efficacy of polyphenolic compounds for hair regeneration: a systematic review and meta-analysis of randomized controlled trials. El Ammari C(1)(2), García-Muñoz AM(3), Zapata-Pérez R(1)(2), Rabad

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a major clinical challenge as a complex multisystemic disorder with no well-established pathophysiological mechanism, characterized by persistent fatigue and post-exertional malaise, along with unrefreshing sleep, cognitive impairment, and impaired stress recovery. Despite decades of investigation into the hypothalamic-pituitary-adrenal (HPA) axis, a definitive neuroendocrine hallmark has remained elusive due to inconsistent findings across various cortisol matrices. Therefore, this systematic review and meta-analysis aimed to provide an integrated understanding of HPA-axis regulation in ME/CFS. We identified 46 case-control studies (comprising 46 independent datasets, including 12 pharmacological challenge studies), involving 1388 ME/CFS patients (71.9% female; mean age 37.3 ± 6.2 years) and 1349 matched healthy controls. Meta-analyses showed lower salivary cortisol at awakening and in the morning. Reductions were also observed in 24-h urinary cortisol and hair cortisol. In pharmacological challenge tests, patients exhibited impaired cortisol release in response to adrenocorticotropic hormone (ACTH) stimulation and exaggerated suppression following glucocorticoid administration. Collectively, these alterations indicate reduced free cortisol availability and enhanced HPA-axis negative feedback sensitivity, consistent with a hyporeactive endocrine state in ME/CFS. This neuroendocrine hypo-reactivity may underlie hallmark clinical features such as unrefreshing sleep, post-exertional malaise, and severe fatigue, as well as cognitive slowing, emotional blunting, and diminished stress resilience frequently observed in ME/CFS and related functional disorders. Integrating neuroendocrine and psychological perspectives may help clarify mechanisms of chronic stress maladaptation and inform psychobiological interventions for fatigue syndromes. © 2026. The Author(s), under exclusive licence to Springer Nature Limited.

BACKGROUND: High-curl-pattern hair has unique structural characteristics that increase its susceptibility to breakage and to seborrheic dermatitis (SD). AIMS: The paper discusses the challenges in effectively treating patients with high-curl-pattern hair and SD, and the role of ceramide-containing products in improving the condition. METHODS: Following a systematic literature review, a panel of dermatologists developed five consensus statements on the relationship between SD and scalp barrier health in hair with a high curl pattern. RESULTS: Certain hair care practices common among individuals with high-curl-pattern hair may contribute to the development or exacerbation of SD, leading to considerable psychological distress. These statements reflect expert opinion and highlight key treatment challenges in this population. CONCLUSION: Further research is needed to better understand racial and ethnic variations in SD and to support individualized, culturally sensitive approaches to its treatment and management. © 2026 The Author(s). Journal of Cosmetic Dermatology published by Wiley Periodicals LLC.

ObjectiveTo evaluate glucagon-like peptide-1 receptor agonist (GLP-1 RA)-specific associations with hair loss, characterize reported alopecia subtypes and discuss potential underlying mechanisms.MethodsA systematic literature search was conducted across four databases (PubMed, Embase, Scopus, and Web of Science) according to PRISMA guidelines and registered in PROSPERO (CRD420261297384). Studies were included if they were primary articles assessing hair loss related to GLP-1 RA use.ResultsOf 133 studies identified, 24 met inclusion criteria. Among GLP-1 RAs, semaglutide and tirzepatide demonstrated the highest incidence rates of hair loss and more frequent signal detection in pharmacovigilance studies. Although infrequently classified overall, androgenetic alopecia and telogen effluvium were the predominant subtypes of hair loss reported. Tirzepatide, associated with the greatest magnitude of weight loss, was most frequently linked to telogen effluvium. Hair loss associated with semaglutide appeared to be dose-dependent, with doses < 2mg weekly rarely implicated while higher obesity-treatment doses were more commonly associated with hair loss. Females appeared to be disproportionately affected. Rapid weight loss emerged as a potential contributor, particularly for telogen effluvium. In contrast, fewer studies assessed hair loss with liraglutide, dulaglutide, lixisenatide and exenatide, and they typically exhibited lower reported risk when compared to semaglutide and tirzepatide.ConclusionsAccumulating evidence from pharmacovigilance databases and clinical cohorts suggests an increased risk of hair loss with certain GLP-1 RAs, particularly semaglutide and tirzepatide. Further studies are needed to clarify the etiology of drug-induced weight loss, identify vulnerable populations, and establish causality and temporal relationship through large, prospective randomized trials.

BACKGROUND: Hair loss is a common condition affecting both men and women, with significant psychosocial impact. While oral supplements are marketed to improve hair growth, their clinical efficacy remains debated. This systematic review aimed to evaluate the effectiveness and safety of commercial oral nutraceuticals for hair growth. METHODS: For this systematic review, a comprehensive search was undertaken in PubMed, Embase, Cochrane CENTRAL, and Web of Science. Eligible studies included randomized controlled trials (RCTs), open-label trials, and proof-of-concept studies evaluating oral supplements in adults (≥ 18 years) with alopecia or hair thinning. Primary outcomes included objective measures including hair counts, density, growth rate, tensile strength, and pull test. Secondary outcomes were investigator/patient assessments and adverse events. RESULTS: A total of 14 studies, including 967 participants, were included. Supplements assessed included Ceramosides, Nutrafol, Nourkrin, Lambdapil, Viviscal, Forti5, GFM oral supplement, and Cynatine HNS. Most trials were RCTs with durations of 12 weeks to 12 months. Meta-analysis demonstrated significant improvements with oral supplements versus placebo: reduced telogen hair density (mean difference [MD] -5.91, 95% confidence interval [CI] -6.74 to -5.08, p < 0.00001), increased anagen hair density (MD 10.48, 95% CI: 8.81 to 12.14, p < 0.00001), and reduced telogen proportion (MD 3.08, 95% CI: -3.35 to -2.81, p < 0.00001). Similarly, significant differences were observed regarding anagen proportion, elongation, and hairs extracted on a pull test (p < 0.00001 for all). Total hair count showed no significant difference (p = 0.06). Patient-reported outcomes consistently favored supplements, reporting improved thickness, reduced shedding, and better satisfaction. Adverse events were minimal, and safety profiles were favorable. CONCLUSIONS: In conclusion, supplements show promising preliminary results, but more rigorous, independent research is needed to confirm these findings. © 2026 The Author(s). Journal of Cosmetic Dermatology published by Wiley Periodicals LLC.

BACKGROUND: Hair type classification is crucial for developing personalized hair care, maximizing hair health, and selecting appropriate treatment for scalp disorders, yet it remains underutilized in clinical practice. AIMS: This review aimed to address three main questions: (1) How can hair types be defined according to specific shape criteria, without referring to race/ethnicity? (2) Why does certain hair exhibit a curly pattern, and how does curly hair behave uniquely? (3) How is the classification of curly hair clinically relevant to the development of seborrheic dermatitis? METHODS: PubMed and Google Scholar were the primary and secondary platforms used for the literature search, respectively. The scope of the search included English-language human studies published between 2000 and 2025 that investigated classification systems defining hair types based on specific shape criteria. RESULTS: The literature review revealed four mainstream hair classification systems: the André Walker Hair Typing System, the LOIS Hair Typing System, the FIA Hair Typing System, and the L'Oréal Curl Classification System. There are shared characteristics across the systems, as each was built on previous ones to incorporate nuances of different hair types and curl patterns. The L'Oréal Curl Classification System acknowledges the broader continuum of hair types by categorizing straight, wavy, curly, and coiled hair using four morphological parameters. CONCLUSIONS: There are several existing hair classification systems that dermatologists and other health care professionals can use to optimize communication with patients. Dermatologists' use of these classification systems and increased awareness of practices for high-curl-pattern hair could ultimately improve treatment outcomes. Curl pattern classification may also have predictive value in the treatment of scalp diseases (e.g., seborrheic dermatitis), but further validation is required. © 2026 The Author(s). Journal of Cosmetic Dermatology published by Wiley Periodicals LLC.

Most epidemiologic evidence linking per- and polyfluoroalkyl substances (PFAS) to reproductive outcomes relies on serum biomarkers, which may not accurately reflect exposure in target reproductive compartments. We systematically reviewed literature (1 Jan 2020 - 31 Dec 2025) investigating PFAS in non-serum matrices (follicular fluid, placenta, semen, human milk, urine, and hair). Following PRISMA 2020 guidelines, we identified 58 eligible studies (19 primary associations; 39 biomonitoring/mechanistic). Study quality was assessed via the Newcastle-Ottawa Scale, with most association studies rated as 'Good.' While findings were heterogeneous across matrix-outcome domains, consistent signals emerged for follicular-fluid PFAS and impaired embryo quality, and placental PFAS and sex-dimorphic fetal growth restriction. Toxicokinetic data revealed high transfer efficiencies for PFOA into follicular fluid (0.72-0.94) but significant retention of PFOS in placental tissue. These findings suggest that non-serum biomarkers provide a time-resolved, compartment-specific perspective that offers greater etiological resolution than systemic serum measurements. Future research should adopt this "matrix-aware" framework to better characterize localized reproductive risks and improve environmental risk assessments.

BACKGROUND: Androgenetic alopecia (AGA) is the most common cause of progressive hair loss, significantly affecting quality of life. Current therapies, such as minoxidil, finasteride, and hair transplantation, show variable efficacy and may be associated with adverse effects. Platelet-rich plasma (PRP), an autologous preparation enriched with platelets and growth factors, has recently gained attention as a regenerative option for hair restoration. OBJECTIVE: This review summarizes advances in PRP therapy for AGA, focusing on preparation techniques, mechanisms of action, clinical efficacy, and safety, and provides recommendations for protocol optimization and future research. METHODS: A systematic search of PubMed, Web of Science, Embase, Cochrane Library, and CNKI was conducted for studies published between 2000 and 2025. Eligible articles included randomized controlled trials, cohort studies, case-control studies, and meta-analyses evaluating PRP preparation methods or therapeutic outcomes. Study quality was appraised using the Cochrane Risk of Bias, ROBINS-I, and GRADE frameworks. RESULTS: PRP promotes follicular regeneration through angiogenesis and activation of Wnt/β-catenin, MAPK, Akt/ERK, and Notch signaling pathways. Clinical trials demonstrate improved hair density, thickness, and patient satisfaction, particularly when PRP is combined with minoxidil, microneedling, or laser therapy. Reported adverse events are mild and transient, such as localized pain or erythema. Nevertheless, heterogeneity in centrifugation, activation, and delivery protocols contributes to inconsistent outcomes across studies. CONCLUSION: PRP represents a promising, safe, and minimally invasive therapy for AGA. Establishing standardized preparation protocols and conducting large-scale randomized studies are essential to confirm long-term efficacy and integrate PRP into routine, personalized AGA management. © 2026 The Author(s). Journal of Cosmetic Dermatology published by Wiley Periodicals LLC.

BACKGROUND: Alopecia areata (AA) is characterized by hair loss triggered by an autoimmune response that leads to emotional distress and a poor quality of life. However, conventional treatments may also have potential side effects. Therefore, traditional medicine methods such as acupuncture are emerging as alternative treatments for AA, with recent evidence suggesting their effectiveness and prompting further research to assess their safety and efficacy. METHODS: This systematic review aimed to evaluate the current evidence regarding AA treatment using acupuncture. We searched 13 databases until December 2024 for studies that compared the efficacy of acupuncture and Western medicine in treating AA. The present review solely targeted randomized controlled trials (RCTs). The risk of bias was assessed using the Risk of Bias tool (ROB), whereas the quality of evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation approach. RESULTS: Eleven RCTs with 1144 participants were included in this review. The included studies had an unclear risk of bias in most domains. Among these, 7 RCTs tested the total treatment effects of combining plum-blossom needling with western medicine compared with western medicine alone. The results revealed that combining plum-blossom needling with western medicine resulted in a higher rate of improved symptoms than using western medicine alone (RR 1.09, 95% CI 1.03-1.16, I2 = 50%, P = .005, 7 RCTs, 756 participants, low certainty of evidence). CONCLUSION: This review provides evidence for the benefits of acupuncture in AA treatment. However, the quality of the evidence was low, and the sample size was small. Therefore, future large-scale studies should be conducted using more rigorous methodologies.

BACKGROUND: Upholding a sterile environment in orthopedic surgery is vital to minimize surgical site infections (SSIs). Among personal protective equipment, beard covers for surgical staff with facial hair have been recommended as a measure to prevent contamination. However, their effectiveness in reducing SSIs remains uncertain, especially in orthopedic procedures that often involve high-risk implants and extended exposure of surgical fields. This systematic review assesses the current evidence on the role of beard covers in infection prevention during surgery. METHODS: Using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, databases were searched for studies investigating facial hair, beard covers, and infection risk. Eligible studies included comparative studies, laboratory experiments, and consensus statements. Quality was assessed using MINORS and CASP tools, while certainty of evidence was graded using the Grading of Recommendations, Assessment, Development and Evaluations criteria. RESULTS: A total of 538 studies were extracted from databases, of which 8 met inclusion criteria. Clinical studies did not demonstrate a statistically significant difference in SSI rates between uncovered bearded surgeons, uncovered clean-shaven surgeons, or with the use of beard covers. Laboratory studies provided mixed results on bacterial shedding associated with facial hair. A consensus statement highlighted insufficient evidence to recommend beard covers as standard practice. CONCLUSIONS: The current evidence is equivocal when determining the role for beard covers for SSI reduction in orthopedic surgery. Given the lack of evidence-based data, further high-quality research is needed to justify the routine use of beard covers in infection prevention and operating room protocols.

BACKGROUND: Comparative studies among different autologous platelet concentrate types for FPHL remain lacking. METHODS: Patients with FPHL (Sinclair gradeII-III) were enrolled and randomized to receive 4 sessions of PRP, i-PRF or CGF treatment at 4-week intervals. The primary endpoint was the inter-group comparison of the non-vellus target area hair count (TAHC)-increase (%) at 24 weeks. Secondary endpoints included: within-group changes in TAHC from baseline; within-group changes in hair diameter (HD) from baseline and inter-group comparison of HD-increase (%) at 24 weeks; Growth factor concentrations were quantified to explore correlations with efficacy. RESULTS: Seventy-four patients completed the study. Post-treatment TAHC increased significantly from baseline in all groups (all p < 0.05). The TAHC-increase(%) was significantly greater in the CGF (27.11 ± 14.80%) and i-PRF (26.54 ± 11.46%) groups compared to the PRP group (14.53 ± 8.65%; p < 0.05), with no significant difference between CGF and i-PRF. Regarding HD increase, all three groups showed improvement, with no statistically significant differences observed among groups (p > 0.05). The i-PRF group showed the lowest adverse event rate. Vascular endothelial growth factor (VEGF) concentration demonstrated a significant positive correlation with the percentage increase in TAHC (r = 0.527, R2=0.278, p < 0.05). CONCLUSIONS: CGF and i-PRF demonstrated superior efficacy in increasing TAHC in FPHL patients. The i-PRF group had the lowest adverse event rate. VEGF levels may play a potential role in promoting hair growth.

BACKGROUND: Although most dandruff shampoos are effective, many leave hair dry and unmanageable, potentially impacting patient compliance and treatment outcomes. OBJECTIVE: This study compared the efficacy, tolerability, and cosmetic benefits of 0.6% micronized selenium disulfide shampoo (SeS2) to 2% ketoconazole shampoo. METHODS: Eighty-seven male and female subjects with moderate to severe dandruff participated in a single-center, 6-week, randomized, double-blind study comparing the benefits and attributes of the shampoos. RESULTS: After 6 weeks of use, Total Scale Score (TSS) decreased by 69.5% in the ketoconazole group, and 77.9% in the SeS2 group, and Symptomatic Scale of Seborrheic Dermatitis (SSSD) decreased by 68.0% in the ketoconazole group and 74.5% in the SeS2 group (all P&lt;0.001). Pruritus severity score decreased by 76.2% and 75.9% in the ketoconazole and SeS2 groups, respectively, and global efficacy and satisfaction, as assessed by blinded dermatologic evaluation, showed significant improvement with both products (all P&lt;0.001). There was no significant difference between the two groups for these outcomes at any time point. Tolerability was excellent for both products. In terms of cosmesis, subjects across diverse curl types favored the SeS2 shampoo with significantly more agreeing that the SeS2 shampoo leaves hair soft, supple, glossy, natural appearing, and was suitable for their hair type when compared to ketoconazole (P&lt;0.001). CONCLUSION: This micronized 0.6% SeS2 shampoo is as effective as 2% ketoconazole shampoo for treating moderate to severe scalp seborrheic dermatitis and provides superior cosmetic benefits across diverse curl types. &nbsp.

BACKGROUND: Tenosynovial giant cell tumour (TGCT) is a rare, locally aggressive neoplasm that affects otherwise healthy adults. There are few systemic treatment options, highlighting an unmet need. We report the results of part 1 of the MANEUVER trial, which aimed to evaluate the efficacy and safety of pimicotinib, a highly selective, potent, colony-stimulating factor-1 receptor inhibitor, in patients with TGCT. METHODS: MANEUVER is a randomised, placebo-controlled, phase 3 study done in 40 specialised hospitals in Asia, Europe, and North America. Patients aged 18 years and older with unresectable, symptomatic TGCT (patient-reported worse stiffness or worst pain of at least 4 on a scale of 0-10) were randomly assigned (2:1, double-blind) to oral, once-daily pimicotinib 50 mg or placebo for 24 weeks (part 1). An independent statistician used a central interactive web response system to generate the randomisation schedule; stratification was by region (China vs non-China). Masking was achieved by using placebo identical in appearance to pimicotinib. In part 1, patients, all investigators, and study funders were masked to treatment assignments. All patients who completed part 1 were allowed to continue to open-label part 2: pimicotinib-treated patients could continue the same dosage and placebo-treated patients could cross over to receive pimicotinib for 24 weeks. Eligible patients who completed part 2 were allowed to continue once-daily pimicotinib long-term in part 3. The primary endpoint was objective response rate (ORR) at week 25 by blinded independent review committee per Response Evaluation Criteria in Solid Tumors version 1.1 in the intention-to-treat population (all randomised patients). Safety was analysed in patients who received at least one dose of study drug. Missing data were not imputed and only observed data were analysed. Trial enrolment is complete; the study is registered at ClinicalTrials.gov (NCT05804045) and is ongoing. FINDINGS: Between April 27, 2023, and March 29, 2024, 126 patients were screened and 94 patients (China [n=45], non-China [n=49]) were randomly assigned to, and received, pimicotinib (n=63) or placebo (n=31). 30 (32%) patients

The objective of this study was to evaluate the potential applications of low-molecular-weight collagen peptides (LMWCPs), produced through enzymatic hydrolysis of fish skin-derived gelatin using a specific protease. LMWCP is enriched in Gly-X-Y tripeptide sequences, particularly Gly-Pro-Hyp (GPH). Preliminary human pharmacokinetic data showed that oral LMWCP markedly increased systemic exposure to GPH, yielding an approximately 54-fold higher area under the concentration-time curve from 0 to 2 h (3388 ± 1084 ng·h/mL) than general collagen. In a subsequent randomized, placebo-controlled trial, 114 women aged 20-50 years with thigh cellulite and self-reported hair thinning received either LMWCP (1000 mg/day) or placebo for 24 weeks. Efficacy endpoints included cellulite severity, dermal-subcutaneous border length, skin roughness, skin elasticity, and hair diameter. The LMWCP group demonstrated significant improvements in cellulite severity, dermal-subcutaneous border length, skin roughness, and skin elasticity at weeks 12 and 24 compared to the placebo group. Hair diameter also increased significantly at week 24, with a larger proportion of participants in the LMWCP group exhibiting measurable hair thickening. These findings indicate that LMWCP, characterized by high GPH content and enhanced systemic exposure resulting from targeted enzymatic hydrolysis, exerts beneficial effects on both skin and hair parameters. Daily intake of LMWCP for 24 weeks effectively reduces thigh cellulite and promotes hair thickness, supporting its potential as an orally administered functional ingredient for skin and hair health.

IMPORTANCE: Apolipoprotein L1 locus (APOL1) high-risk alleles are associated with incidence of chronic kidney disease (CKD) among people with African ancestry. Few studies have examined the effect of genetic return of results on blood pressure (BP) management and control. OBJECTIVE: To determine whether providing APOL1 high-risk genotype results to people with hypertension and their clinicians would reduce systolic BP (SBP) and improve CKD screening and diagnosis. DESIGN, SETTING, AND PARTICIPANTS: From July 1, 2020, to September 30, 2023, adults aged 18 to 70 years with hypertension and self-reported African ancestry were enrolled at 14 institutions and 54 clinical sites across the US. Eligible patients either (1) lacked diagnoses of diabetes and CKD or (2) had a diagnosis of CKD with or without diabetes. INTERVENTIONS: Participants were randomized to receive APOL1 genotype results immediately (intervention) or 6 months after enrollment (control). Clinical decision support encouraged appropriate CKD screening, diagnosis, and antihypertensive therapy. MAIN OUTCOMES AND MEASURES: The primary outcome was change in SBP in individuals with APOL1 high-risk allelles at 3 months, assessed in a modified intention-to-treat analysis. Prespecified per-protocol subgroup analyses included those with uncontrolled BP (baseline SBP ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg), uncontrolled BP while receiving antihypertensive therapy, and CKD at enrollment. Secondary outcomes included urine microalbumin screening and new CKD diagnoses. RESULTS: Of 6754 individuals recruited (mean [SD] age, 55.3 [10.3] years; 4310 women [63.8%]), 954 (14.1%; mean [SD] age, 54.9 [10.0] years; 600 women [62.9%]) had 2 APOL1 risk alleles. At 3 months, there was no difference in SBP between the intervention and control groups (between-group difference, -0.3 mm Hg [95% CI, -2.7 to 2.1 mm Hg]). Among 377 individuals with uncontrolled BP, the mean SBP change was -4.1 mm Hg (95% CI, -7.7 to -0.5 mm Hg) more in the intervention group than the control group (P = .004). SBP improvement was also observed for the intervention in the subgroup of patients with uncontrolled BP receiving antihypertensive the

OBJECTIVES: Facial hair development is a crucial aspect of gender affirmation for transgender men. Despite testosterone therapy, incomplete facial hair growth remains a common concern. This randomized, double-blind, placebo-controlled trial evaluated topical 3% minoxidil for facial hair enhancement in 69 transgender men on stable gender-affirming hormone therapy (GAHT). METHODS: This randomized, double-blind, placebo-controlled trial enrolled 69 transgender men on stable GAHT, registered on the Thai Clinical Trials Registry (TCTR20220205004). Participants were randomized 1:1 to receive topical 3% minoxidil or vehicle placebo twice daily for 12 weeks. Primary outcomes were changes in hair density and diameter assessed via videodermoscopy. Secondary outcomes included modified Ferriman-Gallwey Score (mFGS), Dermatology Life Quality Index (DLQI), and patient satisfaction. RESULTS: The minoxidil group (n = 34) demonstrated significant improvements versus placebo (n = 35) in beard density (11.16 vs. 0.08 hairs/cm2, p = 0.01), beard diameter (5.37 vs. -0.33 μm, p = 0.01), mustache density (18.45 vs. 1.74 hairs/cm2, p = 0.003), and mustache diameter (4.83 vs. 1.31 μm, p = 0.008). Physician and patient-assessed mFGS showed significant improvements with minoxidil (p < 0.05). Quality of life improved markedly (median DLQI: 5 to 1.5 vs. 4 to 3, p < 0.05), with higher patient satisfaction scores (8.16 vs. 5.36, p < 0.001). Adverse events were minimal and comparable between groups. CONCLUSIONS: Topical 3% minoxidil represents an effective, safe, and well-tolerated adjunctive treatment for facial hair enhancement in transgender men receiving GAHT.

BACKGROUND: Androgenetic alopecia (AGA) is the most common form of hair loss, marked by progressive shedding and follicular miniaturization, with advanced stages leading to irreversible follicular loss. Follicular Unit Extraction (FUE) provides favorable outcomes even in patients with reduced follicular density. Concentrated Growth Factors (CGF), a third-generation platelet concentrate rich in growth factors (GFs), may enhance follicular survival, promote growth, and improve density with good safety, yet evidence supporting its combined use with FUE remains limited. OBJECTIVE: This study aims to conduct a prospective clinical comparative trial to evaluate the synergistic effect of CGF when used in conjunction with FUE for the treatment of AGA. METHOD: This study randomized 26 male AGA patients (2022-2024) to receive FUE alone or with CGF injections. Efficacy was assessed via hair density, terminal hair ratio, standardized images, and patient/investigator GAIS satisfaction. Safety was evaluated through adverse event monitoring. RESULTS: Baseline characteristics were comparable. At nine months, the experimental group showed significantly higher hair density and a greater increase in terminal hair proportion than the control group (p < 0.05). CONCLUSION: CGF-assisted FUE significantly improved hair density and terminal hair ratio compared with FUE alone, with favorable safety and high patient satisfaction.

28. J Cosmet Dermatol. 2026 Feb;25(2):e70717. doi: 10.1111/jocd.70717. The Safety and Efficacy of a Novel Saw Palmetto (Serenoa repens) Extract for Promoting Hair Growth in Adults With Self-Perceived Thinning Hair: 180-Day Results. Ablon G(1). Author information: (1)Medical, Surgical, and Cosme

Ritlecitinib is an oral JAK3/TEC family kinase inhibitor approved for individuals aged ≥ 12 years with severe alopecia areata. Here we report interim efficacy and safety results with ritlecitinib up to Month 24 in the Asian subpopulation from the ALLEGRO phase 2b/3 and ALLEGRO-LT studies. Data are reported for participants with Severity of Alopecia Tool score ≥ 50 who received ritlecitinib 50 mg with (200/50-mg group) or without (50-mg group) an initial 4-week 200-mg daily loading dose in ALLEGRO-2b/3, and continued ritlecitinib 50 mg in ALLEGRO-LT. In long-term studies, it is common for summaries at later time points to reflect participants who remained in the study, tolerated the drug, and had a positive treatment response. To account for this, efficacy summaries were presented both as observed and by using the last observation carried forward method. At Month 12, 51.7% and 44.7% (last observation carried forward) of Asian participants in the 50-mg (n = 58) and 200/50-mg groups (n = 47), respectively, achieved Severity of Alopecia Tool score ≤ 20 (≤ 20% scalp hair loss); the respective proportions were 50.0% and 47.8% at Month 24. Of participants who achieved Severity of Alopecia Tool score ≤ 20 at Month 12 in the 50-mg and 200/50-mg groups, 68.2% and 86.7% sustained this response through Month 24, respectively. At Month 12, 74.0% and 57.9% of participants in the 50-mg and 200/50-mg groups, respectively, had an eyebrow hair regrowth response; at Month 24, the proportions were 72.0% and 48.7%. At Month 12, 65.1% and 54.1% of participants in the 50-mg and 200/50-mg groups, respectively, had an eyelash hair regrowth response; the proportions were 65.1% and 52.8% at Month 24. The proportion of participants with a Patients' Global Impression of Change response of "moderately" or "greatly" improved since baseline increased through Month 24 in both groups. Ritlecitinib had an acceptable safety profile, consistent with that in the overall population. Overall, ritlecitinib 50 mg (±200-mg loading dose) demonstrated clinically meaningful and sustained efficacy through Month 24 in the Asian subpopulation, consistent with results in the overall population. Trial Registrati

BACKGROUND: Rib fractures can lead to intense acute pain, chest wall instability, and pulmonary complications in trauma patients, necessitating their admission to critical care units. Furthermore, these lesions represent a source of neuropathic disturbances. OBJECTIVES: The goal was to compare continuous thoracic intervertebral foramen blocks (CTIFBs) to continuous midpoint-to-pleura transverse process blocks (CMTPBs), both guided by ultrasound, for their efficacy in managing acute pain caused by rib fractures. STUDY DESIGN: A double-blind, randomized controlled trial. SETTING: This research was conducted in the Intensive Care Unit (ICU) of San Salvatore Academic Hospital (L'Aquila, Italy) from December 2022 to November 2024. METHODS: Ninety-six adult trauma patients with rib fractures were randomized to receive either the CTIFB (experimental group; n = 48) or the CMPTB (control group; n = 48). The former block was performed by placing the tip of the needle over and behind the transverse process of the vertebra. In the latter block, the needle tip involved the midpoint between the pleura and transverse process. All patients received an initial bolus of 5 mL of levobupivacaine 0.25% with 4 mg of dexamethasone at each fracture level, followed by a continuous infusion (5 mL/h of levobupivacaine 0.25% with 16 mg of dexamethasone). The primary outcome was the proportion of patients who achieved pain control (Numeric Rating Scale [NRS] score <= 3) by 2 hours after the block. The secondary outcomes included neuropathic disturbances (assessed by von Frey hair and Lindblom tests), respiratory parameters (P/F ratio, spirometry, and diaphragmatic motion), and daily morphine consumption. RESULTS: Success (NRS score <= 3) was achieved in 21/48 patients (44%) in the experimental group and 3/48 patients (6%) in the control group (P < 0.001). Patients in the experimental group showed significant reductions in neuropathic disturbances (F(5,470) = 18.5, P < 0.001) and required less daily morphine (10.1 ± 3.9 mg versus 20.8 ± 4.5 mg, P < 0.001). Both groups demonstrated improved respiratory parameters, but patients in the experimental group showed superior airflow rates by 48 hour

The demand for refined anaesthetic protocols in ovine experimental surgery has increased due to ethical considerations and the need to improve perioperative stability. This study evaluated the analgesic efficacy of ultrasound-guided combined sciatic and saphenous nerve blocks using two different local anaesthetics in Hair Canarian Sheep undergoing invasive orthopaedic hindlimb surgery. Fifteen clinically healthy sheep were randomly assigned to one of three groups: lidocaine (2%), bupivacaine (0.5%), or control (general anaesthesia alone). Intraoperative physiological parameters, including heart rate, respiratory rate, and arterial blood pressure, were recorded, and postoperative pain was assessed using a modified Melbourne Pain Scale. Sheep receiving locoregional anaesthesia showed significantly lower postoperative pain scores compared with control animals. Intraoperatively, a significant difference between groups was observed only for respiratory rate, with lower values in the bupivacaine group. The bupivacaine group exhibited lower and more stable respiratory rates, with a trend towards lower heart rates during surgery, as well as consistently lower pain scores during the early postoperative period. Lidocaine provided limited intraoperative and postoperative effects compared with the control group. Respiratory rate appeared to be more closely associated with pain scores than other physiological parameters. In conclusion, ultrasound-guided sciatic and saphenous nerve blocks were associated with improved perioperative analgesia in sheep undergoing orthopaedic surgery. The use of bupivacaine was associated with lower respiratory rates intraoperatively and reduced postoperative pain scores, suggesting a potential benefit in perioperative analgesia.

Scalp microbes are recognized as contributors to hair loss by influencing scalp homeostasis and hair growth. However, the in vitro anti-hair loss activity of microbial culture media derived from healthy scalps remains unclear. In this study, resident microbes from 20 Korean participants with healthy scalps and hair were isolated, and Staphylococcus capitis was used to produce S. capitis ferment filtrate (SCFF). SCFF anti-hair loss activity was evaluated in human follicle dermal papilla cells (HFDPCs) and human adult low-Calcium High-Temperature (HaCaT) keratinocytes via proliferation assays, qPCR, immunocytochemistry, and SA-β-gal staining at 250-1000 μg/mL. SCFF increased cell density after 48 h in a concentration-dependent manner. In HFDPCs, SCFF controlled growth (KGF, IGF-1, and HGF) and androgen (AR and TGF-β2) factors, regulating key mRNAs for hair growth. SCFF mitigated scalp and hair aging by promoting sirtuins 1 and 7 and collagen type 13, while suppressing p21 and X-Gal staining. In HaCaT cells, SCFF exhibited a scalp barrier-strengthening effect by significantly increasing filaggrin and involucrin levels. It suppressed reactive oxidative stress and exhibited DPPH and ABTS radical scavenging activity. These results suggest that SCFF may modulate key pathways associated with hair loss by promoting scalp and hair anti-aging, barrier strengthening, enhancing antioxidant activity, and supporting hair growth.

Background/Objectives: Textile dermatitis seems underdiagnosed, partly due to low awareness of this problem and partly due to imperfect screening methods. The aim of this study was to analyse the diagnostic efficacy and clinical relevance of two textile dye mixes used in routine patch testing. Methods: Retrospective analysis of patch test results and clinical records of patients tested with textile dyes in a specialised patch test practice. Results: Between 2007 and 2024, 207 patients were patch tested with Disperse Blue Mix 106/124 (DBM). Positive reactions were observed in 17.4% of patients, including 10.6% considered clinically relevant. Between 2019 and 2023, 90 patients were tested with Textile Dye Mix (TDM) 6.6%, of whom 14.4% developed a positive reaction, relevant in 4.4%. In a subgroup tested with TDM 6.6%, DBM, all their components and cross-reacting azo dyes, out of eight patients with confirmed textile dermatitis, three cases would have been missed if screening had been performed using TDM alone (6.6%), compared with one case being missed if screening had been performed using DBM alone. The highest rate of positivity (78.6%) to TDM 6.6% was found among patients with an allergy to the common hair dye Toluene 2,5-Diamine Sulfate, all of whom were also positive to Disperse Orange 3 (DO3) present in TDM 6.6%. Among patients with positive tests to Disperse Blue (DB) 106 1% pet. or DB124 1% pet., 68.7% and 85.7%, respectively, reacted also to DBM 106/124 (each component at 0.5%), with respective figures for TDM 6.6% (DB106 and DB124 each at 0.3%) amounting to a mere 12.5% and 14.3%. Conclusions: The detection rates of textile dermatitis can be increased by improving screening tools for textile dye allergy in baseline series for routine patch testing. Based on the results of this study, proposed improvements include removing Disperse Orange 3 from the textile dye mix, tripling the concentrations of Disperse Blue 106 and Disperse Blue 124 in the textile dye mix, and doubling their concentrations in the Disperse Blue Mix 106/124.

Dermal papilla (DP) cells orchestrate hair follicle growth and cycling by secreting signaling molecules that stimulate follicular epithelial stem cells. The signal peptide CUB-EGF-like domain-containing protein 3 (SCUBE3) was recently identified as a potent anagen stimulator secreted by DP cells. Ageratum houstonianum ethanolic extract (AHE) and its active constituent agerarin exhibit anti-inflammatory properties; however, their effects on hair follicle growth remain unclear. This study aimed to investigate the effects of AHE and agerarin on SCUBE3 expression in primary human DP cells and to elucidate the underlying molecular signaling pathway. Cell viability was assessed by measuring cell confluency. Ex vivo hair growth was analyzed using organ cultures of human hair follicles. Gene and protein expression were determined using reverse transcription-PCR, immunoblot analysis, immunofluorescent staining, tyramide signal amplification-based multiplex immunohistochemistry, and gene promoter-reporter assay in primary human follicle DP cells. In a hair follicle organ culture model, both AHE and agerarin increased the population of the anagen phase and promoted hair shaft elongation. AHE and agerarin significantly upregulated SCUBE3 expression at both the mRNA and protein levels. Mechanistically, AHE and agerarin induced activator protein-1 (AP-1) expression by activating mitogen-activated protein kinase signaling pathways, thereby increasing SCUBE3 gene promoter activity. AHE and agerarin promoted hair follicle growth by upregulating SCUBE3 expression via activation of the MAPK-AP-1 signaling axis. In conclusion, AHE and agerarin may serve as potential therapeutic agents for the prevention and treatment of alopecia (hair loss).

Heavy metals including mercury (Hg), lead (Pb), cadmium (Cd), and arsenic (As) remain significant global toxins due to their environmental persistence, widespread anthropogenic release, and serious biological effects. This review consolidates current understanding of their natural and industrial sources, environmental cycling, human exposure routes, and population-level vulnerabilities. It covers their toxicokinetics and toxicodynamics, emphasizing species-specific absorption, distribution, and injury mechanisms, including oxidative stress, thiol binding, mitochondrial dysfunction, endocrine disruption, and cancer risk. Clinical signs range from subtle neurocognitive impairment and kidney damage to severe acute poisoning. The review evaluates evidence-based approaches to risk assessment and biomonitoring, such as blood, urine, hair, and speciation tests, noting issues, including unvalidated provoked testing. Treatment focuses on removing exposure, providing nutritional support, and offering supportive care, with chelation therapy reserved for specific cases. It explains the chemistry, pharmacology, and roles of chelating agents-ALA, DMSA, DMPS, Cys, GSH, and physiologic thiols, comparing their effectiveness, limitations, and costs for various metals. Emerging therapies, precision toxicology, and public health strategies are discussed within a prevention-focused context. Unlike prior reviews focused primarily on toxic mechanisms or isolated clinical management, this review integrates mechanistic toxicology, biomarker interpretation and speciation, evidence-based clinical care, and ethical, cost-conscious decision-making within a single translational framework. This narrative review synthesizes foundational and contemporary literature published through 2025, with particular emphasis on studies published since 2000 that inform toxicokinetics, biomarker interpretation, diagnostics, clinical management, and prevention.

Traditional chemical hair dyes are associated with potential health risks, while botanical alternatives are often hampered by poor stability and limited color longevity. In this study, discarded squid ink was used to prepare bionic hair colorants of high performance. By synergizing ultrasound disruption with enzymatic hydrolysis, the crude ink aggregates were transformed into highly uniform squid ink melanin nanoparticles (SIMNPs) with size and zeta potential of ~174 nm and -37.5 mV, respectively. This effectively improved the solubility but reduced the steric limitation of natural melanin. To overcome the weak affinity between melanin and human hair, a biomimetic interface where Fe(III) ions act as supramolecular bridges was further engineered to stably bind the SIMNPs to hair keratin. Under optimized conditions (pH 8.0, 45 °C, and 80 min), the dyed hair achieved a natural deep black with a total color difference (ΔE*) of 68.79 ± 0.29, which was maintained at 63.19 ± 0.27 even after 13 consecutive water washing cycles. Unlike destructive oxidative dyes, this SIMNP dyeing system assisted by coordination-driven assembly preserved the native α-helical architecture and disulfide bond networks of hair keratin. Furthermore, the deposited SIMNP layer effectively protected hair fibers from ultraviolet (UV) damage due to its powerful UV-shielding capacity. Crucially, in vitro and in vivo evaluations confirmed the exceptional biosafety of this formulation, demonstrating robust cellular tolerance and absence of murine skin irritation. The work demonstrates a green, low-damage paradigm for the development of bio-based hair colorants of high performance and presents a promising pathway for the high-value utilization of marine by-products.

Hair serves essential functions, including mechanical sensing, head protection, and body temperature regulation, while also playing a significant role in human aesthetics. However, factors such as hormonal imbalances, autoimmune disorders, infections, and psychological stress contribute to the widespread issue of hair loss, particularly among the elderly, adversely affecting self-confidence and self-esteem. Although treatments such as minoxidil, finasteride, and dutasteride have received regulatory approval, their associated side effects, such as sexual dysfunction, neuropsychiatric issues, and cardiovascular symptoms, can impede patient recovery. While follicular unit transplantation and stem cell therapy show promising outcomes, they are not suitable for all types of hair disorders. Short peptides that mimic intracellular signals and exhibit diverse biological effects have emerged as a promising approach for stimulating hair regrowth. By combining different formulations and nanosystems, the limitations of short peptides can be effectively addressed. This review systematically summarizes recent advances in peptide-based treatments for hair loss, highlighting their advantages and limitations.

Bronchial asthma (BA) is a major public health problem worldwide and represents a significant health burden in Saudi Arabia. The prevalence and risk factors of asthma vary across regions and are influenced by genetic, environmental, occupational, and lifestyle-related factors. A cross-sectional epidemiological study was conducted among 738 adults residing in the Makkah region of Saudi Arabia. Data were collected using a self-administered questionnaire that included sociodemographic characteristics and potential risk factors for asthma. Crude and adjusted odds ratios were calculated to assess associations between participant characteristics and self-reported BA. Of the 738 participants, 192 (26.0%) reported having BA. Asthma prevalence differed significantly across cities within the Makkah region (Taif, Makkah, and Jeddah) and among individuals who lived or worked near factories (P < .01). Among asthma patients, 76.6% reported using asthma medications. The most frequently reported environmental and lifestyle exposures included the use of chemicals in cleaning, farming, or hair styling (76.6%), use of air conditioners (73.4%), and use of firewood for heating or cooking (70.3%). Passive smoking was reported by 57.3% of patients, while 46.0% were active smokers. The prevalence of BA among adults in the Makkah region was considerable and varied by geographic location and environmental exposure. Living or working near factories and exposure to indoor and occupational risk factors were associated with asthma. These findings underscore the importance of addressing regional environmental and occupational factors in asthma prevention and management strategies in Saudi Arabia.

Diphenhydramine and cyclizine are over-the-counter (in many countries) antihistamines that have considerable sedative effects. Therefore, they can be used in drug-facilitated crimes to incapacitate victims. There is a knowledge gap regarding detection possibilities and concentration levels of these antihistamines in hair. This study aimed to investigate whether a single dose of diphenhydramine and cyclizine could be quantified in head hair, and for how long. A single-dose study was conducted in which 12 adult volunteers ingested a single dose of diphenhydramine (25 mg) and cyclizine (44 mg). Hair samples were collected before drug intake and at 1, 3, 5, and if possible, 12 months after intake. To quantify a single dose of antihistamines in head hair, a validated LC-MS/MS method with a lower limit of quantification of 1 pg/mg was applied. Both antihistamines and their main metabolites, N-demethyldiphenhydramine and norcyclizine, were detected in all hair samples collected up to 5 months after intake. Twelve months after intake, diphenhydramine was quantifiable in 25% and cyclizine in 62.5% of available hair samples. The concentrations found in hair within 1 year after intake ranged from 0 to 610 pg/mg for diphenhydramine and from 0 to 590 pg/mg for cyclizine. The median decrease in concentration over 2, 4, and 11 months was 43%, 70%, and 100% for diphenhydramine and 40%, 64%, and 98% for cyclizine. The data obtained provided indicative concentration ranges for a single oral dose of diphenhydramine and cyclizine in hair, thereby improving the interpretation of hair analyses in forensic casework. © 2026 The Author(s). Drug Testing and Analysis published by John Wiley & Sons Ltd.

Reliable drug delivery to the inner ear is still an unmet clinical need, due to the blood cochlear barrier, which effectively protects this highly sensitive organ. To overcome this hurdle, miniaturized, biodegradable implants were prepared (0.3 mm in diameter), which can be administered into the cochlea via a tiny hole drilled into the round window. They were based on poly(lactic-co-glycolic acid) (PLGA) and prepared by hot melt extrusion. Three drugs were incorporated: (i) 20.0% dexamethasone with anti-inflammatory, anti-fibrotic and protective activity for hair cells (being critical for hearing); (ii) 5.7% lidocaine (free base) as local anesthetic drug and therapeutic potential to treat tinnitus or vertigo; and (iii) 2.1% curcuminoids for their anti-inflammatory and anti-oxidant activities. The implants were thoroughly characterized before and after exposure to artificial perilymph in vitro, by DSC, X-ray diffraction, GPC, optical microscopy, TGA and release measurements. In addition, they were implanted into gerbil cochlea, monitoring the resulting local drug concentrations. Importantly, the implants allowed for the simultaneous controlled release of all drugs. In vitro, lidocaine release was fastest (100% after 10 d), followed by dexamethasone (100% after 10 weeks). The slower release of dexamethasone can be explained by saturation effects within the implant. In vivo, drug release was faster, probably because of accelerated polymer degradation due to local drops in pH and/or the presence of esterases (e.g., 100% dexamethasone release in 2 weeks). Curcuminoids were not detectable in the release medium under the given conditions in vitro, nor in the perilymph in vivo, because of their very limited solubility in aqueous media. Visual observation suggests that they were released within 1-2 weeks in vivo (likely partitioning into lipid phases and/or being metabolized). No noteworthy changes in the animals' behavior or signs for tissue inflammation/damage were detected.

Onychopapilloma (OP) is a benign tumor of the nail. In all studies of the literature including the World Health Organization new classification of nail tumor, OP is proposed as a tumor originating in the distal matrix and defined histologically by its onychogenic property as "matrix metaplasia of the nail bed."The aim of this study is to clarify the origin and type of keratinization of OP, to emphasize the application of clear histological criteria according to the type of surgical procedure, to present new clinical and histological subtypes of OP, and to discuss the differential diagnosis.Eighty-six cases were available for clinicopathologic review. Detailed clinicopathological analysis could be performed on 56 cases.In addition to the classic clinical presentations of longitudinal erythronychia, longitudinal leukonychia, longitudinal melanonychia, 2 cases presented an unusual band pattern in the form of xanthonychia. Histological interpretation was more difficult for samples obtained by tangential longitudinal excision than for those obtained by longitudinal monobloc excision. The superficial eosinophilic layer of the nail bed was either clearly identified by its round to oval nuclei or showed features simulating a keratogenous zone by foci of irregularly contoured pycnotic nuclei. In all cases, the so-called matrix metaplasia of the nail bed corresponded to an onycholemmal keratinization with 2 types of cornified cells: clear cells either parakeratotic or orthokeratotic, and eosinophilic cells. The clear orthokeratotic cornified cells sometimes simulated abnormal enlarged onychocytes. The onychogenic marker including hair related keratin (HK) 31, HK85, HK86, LEF-1, and beta-catenin were not expressed in the

Comment on J Am Acad Dermatol. 2021 Aug;85(2):478-480. doi: 10.1016/j.jaad.2018.04.032.

PURPOSE: Telogen effluvium (TE) is defined as a diffuse hair loss characterized by shortening of the anagen phase and precipitation of the telogen phase, with a consequent reduction of total hair volume. Nutritional supplementation is indicated under conditions in which TE is related to dietary disorders. The aim of this clinical study was to compare the efficacy of two different supplements in monotherapy for TE. PATIENTS AND METHODS: Female adult patients were randomized to receive two oral nutritional supplements (group 1: a supplement composed of zinc, biotin, iron, vitamins A, C, E, and B complex, folic acid, magnesium, and amino acids of keratin and collagen and group 2: calcium pantothenate cystine, thiamine nitrate, medicinal yeast, keratin, and aminobenzoic acid) to treat hair loss for 180 days. They were evaluated clinically and by digital trichoscopy. RESULTS: Clinical evaluation showed significant clinical improvement (P<0.05) for the evaluated parameters: hair loss, hair volume, density of hair (scalp cover), hair shine, hair strength, in 180 days. At 90 days evaluation, group 1 showed significant improvement for all parameters, while group 2 did not show any significant improvement for hair shine and hair strength. In the digital trichoscopy, there was a significant improvement only in group 1 (11.09%×7.76%) after 180 days. CONCLUSION: In idiopathic TE, the nutritional component should be suspected; the supplementation of an association of nutrients in recommended daily intake can lead to significant improvement of the condition from the first trimester of use. The use of an association with proven efficacy and a safety profile and posologic convenience facilitate its indication and patient adherence.

A growing body of evidence from several laboratories points at nonmechanical functions of keratin intermediate filaments (IF), such as control of apoptosis, modulation of signaling, or regulation of innate immunity, among others. While these functions are generally assigned to the ability of IF to scaffold other proteins, direct mechanistic causal relationships between filamentous keratins and the observed effects of keratin knockout or mutations are still missing. We have proposed that the scaffolding of chaperones such as Hsp70/40 may be key to understand some IF nonmechanical functions if unique features or specificity of the chaperoning activity in the IF scaffold can be demonstrated. The same criteria of uniqueness could be applied to other biochemical functions of the IF scaffold. Here, we describe a subcellular fractionation technique based on established methods of keratin purification. The resulting keratin-enriched fraction contains several proteins tightly associated with the IF scaffold, including Hsp70/40 chaperones. Being nondenaturing, this fractionation method enables direct testing of chaperoning and other enzymatic activities associated with IF, as well as supplementation experiments to determine the need for soluble (cytosolic) proteins. This method also permits to analyze inhibitory activity of cytosolic proteins at independently characterized physiological concentrations. When used as complementary approaches to knockout, knoc

L-cysteine is currently recognized as a conditionally essential sulphur amino acid. Besides contributing to many biological pathways, cysteine is a key component of the keratin protein by its ability to form disulfide bridges that confer strength and rigidity to the protein. In addition to cysteine, iron represents another critical factor in regulating keratins expression in epidermal tissues, as well as in hair follicle growth and maturation. By focusing on human keratinocytes, the aim of this study was to evaluate the effect of cysteine supplementation as nutraceutical on keratin biosynthesis, as well as to get an insight on the interplay of cysteine availability and cellular iron status in regulating keratins expression in vitro. Herein we demonstrate that cysteine promotes a significant up-regulation of keratins expression as a result of de novo protein synthesis, while the lack of iron impairs keratin expression. Interestingly, cysteine supplementation counteracts the adverse effect of iron deficiency on cellular keratin expression. This effect was likely mediated by the up-regulation of transferrin receptor and ferritin, the main cellular proteins involved in iron homeostasis, at last affecting the labile iron pool. In this manner, cysteine may also enhance the metabolic iron availability for DNA synthesis without creating a detrimental condition of iron overload. To the best of our knowledge, this is one of the first study in an in vitro keratinocyte model providing evidence that cysteine and iron cooperate for keratins expression, indicative of their central role in maintaining healthy epithelia. © 2015 Wiley Periodicals, Inc.

Sulphur-containing amino acids (SAA) are essential and usually the first limiting amino acids for growth, milk and wool production. The keratin fibre that grows from epidermal tissue is rich in SAA. The rate of fibre growth and its S content are influenced by the availability of SAA. Betaine is a dietary source for a labile methyl group and actively participates in methionine metabolism by donating methyl groups for the remethylation of homocysteine to methionine. Ruminants are capable of synthesizing SAA from inorganic S sources, and most bacteria in the rumen can use inorganic S to meet their requirements for growth. The objective of this study was to examine whether betaine and an inorganic sulphur supplement could provide methyl groups and sulphur amino acids in a way that growth performance and wool production of ewes and lambs are improved. Treatments performed included betaine supplementation, sulphate supplementation and betaine plus sulphate supplementation with five replications for each treatment. The dry matter intake of the ewes was affected by betaine plus sulphate supplementation (p < 0.05). In the ewes, betaine plus sulphate supplementation increased (p < 0.05) the wool growth rate, wool yield, staple length and wool sulphur concentration, while decreasing wool wax and wool yellowness (p < 0.05). In the lambs, wool growth rate, wool yield, fibre diameter, staple length, staple strength, wool sulphur concentration, wool wax and fibre percentage did not differ (p > 0.05) between treatments. In the ewes, plasma methionine concentration increased (p < 0.05) with betaine plus sulphate treatment. No corresponding difference (p > 0.05) was observed in plasma methionine concentration in the lambs. It can be concluded that betaine plus sulphate supplementation

In juvenile cattle, vitamin A deficiency is reported most commonly as a neurological condition; only rarely are there dermatologic manifestations. In the current study, alopecia, severe epidermal and follicular orthokeratosis, and acanthosis due to hypovitaminosis A are reported in 2 of 32 Angus calves, with a third animal suspected. Affected animals responded to vitamin A supplementation, and no additional calves displayed signs. Vitamin A acts on skin by regulating DNA transcription in keratinocytes, reducing the number of tonofilaments and desmosomes, both involved in cell-to-cell adhesion. Hence, adequate levels of dietary vitamin A are necessary for normal keratinocyte turnover, and deficiencies result in retention of keratinized cells (orthokeratosis). The present report reminds diagnosticians to consider vitamin A deficiency in cases of orthokeratotic dermatopathy in cattle.

Dietary selenium is known to protect skin against UV-induced damage and cancer and its topical application improves skin surface parameters in humans, while selenium deficiency compromises protective antioxidant enzymes in skin. Furthermore, skin and hair abnormalities in humans and rodents may be caused by selenium deficiency, which are overcome by dietary selenium supplementation. Most important biological functions of selenium are attributed to selenoproteins, proteins containing selenium in the form of the amino acid, selenocysteine (Sec). Sec insertion into proteins depends on Sec tRNA; thus, knocking out the Sec tRNA gene (Trsp) ablates selenoprotein expression. We generated mice with targeted removal of selenoproteins in keratin 14 (K14) expressing cells and their differentiated descendents. The knockout progeny had a runt phenotype, developed skin abnormalities and experienced premature death. Lack of selenoproteins in epidermal cells led to the development of hyperplastic epidermis and aberrant hair follicle morphogenesis, accompanied by progressive alopecia after birth. Further analyses revealed that selenoproteins are essential antioxidants in skin and unveiled their role in keratinocyte growth and viability. This study links severe selenoprotein deficiency to abnormalities in skin and hair and provides genetic evidence for the role of these proteins in keratinocyte function and cutaneous development.

The role of oestrogen receptors in dogs with hair cycle arrest (alopecia X) was investigated by immunohistochemistry. The purpose of this study was to determine if hair regrowth in dogs with hair cycle arrest treated with melatonin was associated with a decrease in follicular oestrogen receptors. Fifteen Pomeranians (excluding intact females) with hair cycle arrest were enrolled. Two biopsies were obtained from alopecic areas of the trunk before and after 3 months on melatonin. Haematoxylin and eosin-stained tissues were examined and oestrogen receptor-alpha was demonstrated immunohistochemically. Common histopathological findings included hyperkeratosis, follicular keratosis, excessive tricholemmal keratinization (flame follicles), thin epidermis, few small anagen bulbs, epidermal pigmentation and melanin aggregates within follicular keratin. Melanin aggregates within basal cells and hair were an occasional finding. After 3 months, 40% (six) dogs had mild to moderate hair regrowth. Biopsies from six dogs showed histological evidence of an increase in anagen hairs and eight dogs had a decrease in epidermal pigmentation. Moderate to marked staining intensity of oestrogen receptor-alpha was noted in all sebaceous gland basal cells, all small hair bulbs and follicular epithelium of telogen hairs. There was no oestrogen receptor-alpha staining of nuclei within the epidermis, apocrine glands or dermal fibroblasts. Large anagen hair bulbs had minimal to no oestrogen receptor staining. Hair regrowth was not associated with a change in oestrogen receptor-alpha staining.

Overliming and excessive application of superphosphate caused a zinc deficiency in the soil and so reduced the uptake of zinc by fodder plants. Bucks reared on such fodder had significantly (p < 0.01) less zinc in their hair compared with controls and suffered from 'conditioned zinc deficiency syndrome' with a significant (p < 0.01) loss of body weight, stunted growth, alopecia, lethargy, abnormal (kyphotic) gait, anorexia, digestive and respiratory problems. Oral supplementation with zinc sulphate very rapidly improved these conditions to near normality. Histological examination of samples of skin and testis from the zinc-deficient bucks revealed formation of excessive keratin, retention of nuclei in the stratum corneum and reduction in the width of the stratum granulosum in the skin, while samples of testis indicated degenerative changes, including atrophy of the seminiferous tubules, hyperplasia of the germinal epithelium and thickening of the walls of blood vessels.

Several families of proteins are expressed in the growth of hair and an estimated 50-100 proteins constitute the final hair fiber. The cumbersome nomenclature for naming these different proteins has led to a proposal to modify that which is currently used for epidermal keratins. Investigations of the organization of hair genes indicate that the members of each family are clustered in the genome and their expression could be under some general control. Interestingly, the protein called trichohyalin, markedly distinct from the hair proteins, is produced in the inner root sheath cells and the gene for it has been found to be located at the same human chromosome locus as the genes for profilaggrin, involucrin, and loricrin. A mainstream objective is to identify controls responsible for the production in the hair cortex of keratin intermediate filaments (IFs) and two large groups of keratin-associated proteins (KAPs) rich in the amino acids cysteine or glycine/tyrosine. A specific family of cysteine-rich proteins is expressed in the hair cuticle. Comparisons of promoter regions of IF genes and KAP genes, including a recently characterized gene for a glycine/tyrosine-rich protein, have revealed putative hair-specific motifs in addition to known elements that regulate gene expression. In the sheep, the patterns of expression in hair differentiation are particularly interesting insofar as there are distinct segments of para- and orthocortical type cells that have significantly different pathways of expression. The testing of candidate hair-specific regulatory sequences by mouse transgenesis has produced several interesting hair phenotypes. Transgenic sheep over-expressing keratin genes but showing no hair growth change have been obtained and compared with the equivalent transgenic hair-loss mice. Studies of the effects of amino acid supply on the rate of hair growth have demonstrated that with

Intact rat external ear canal explants were maintained either in retinoid-deficient or retinoid-supplemented medium for 7, 10, 14, and 21 days. The morphology of the external ear canal epidermis was well maintained, including the presence of sebaceous glands even after 21 days in culture with retinoid-deficient medium. However, after culturing in retinoid-supplemented medium, the external ear canal epithelium showed both a loss of keratohyalin granules and the formation of keratin. Extensive microvilli formation occurred, even though the desquamation process continued from the superficial layer after 7, 10, and 14 days in culture with retinoid-enriched medium. After 21 days in culture with retinoid-supplemented medium, the ear canal epithelium contained well-developed Golgi apparatus and secretory granules as well. It was concluded that the ear canal epithelium was transformed into a secretory-like mucosal epithelium by retinoid supplementation.

Biotin deficiency in animals causes pathological changes of the skin and its appendages including, for example, exfoliative dermatitis, depigmentation, and alopecia. The hooves of biotin-deficient swine are weak, brittle, and often necrotic. These changes disappear after dietary biotin supplementation. Biotin supplementation also noticeably improves the hoof quality of horses, cattle and swine having no apparent biotin deficiency. In order to elucidate the molecular basis of these effects, the influence of biotin on cytokeratin expression in a keratinocyte cell line (Ha-CaT) was investigated using electrophoretic and immunological techniques. Pharmacological biotin concentrations of 1 microM, and 100 microM in the culture medium caused a specific increase in cytokeratins, which are normally induced upon terminal differentiation of epidermal cells in vivo. The expression of cytokeratins occurring in stratified epithelia independent of differentiation were not affected. These findings show that biotin directly stimulates the differentiation of epidermal cells. Such a molecular mechanism revealed in cell culture could provide an explanation for the therapeutic effects of pharmacological doses of biotin on hoof quality in farm animals.

As llamas become more common in North America, veterinarians will be called on ever more frequently to deal with their dermatologic problems. Adherence to the basic tenets of the thorough dermatologic work up, including history, physical examination, skin scrapings, cytological examinations, fungal culture, skin biopsies, and assessing response to judiciously chosen trial therapies will offer the best opportunity of arriving at proper diagnoses. Special attention must be paid to the fact that llama skin bears some histological differences that may prove confusing to the uninitiated. A mild degree of hyperkeratosis, a prominent vascular plexus in the superficial dermis that is associated with mild perivascular mononuclear cell accumulations, and regional differences in sebaceous gland size and numbers, all are considered normal findings. Ectoparasites, including sarcoptic mange, chorioptic manage, and pediculosis, appear to be the most common causes of pruritus in the llama. Although ivermectin therapy would appear to be very effective for the treatment of scabies and, indeed, may work well against sucking lice, chorioptic mange and biting lice usually do not respond to this medication. Corticosteroids can be used to treat pruritus in the llama nonspecifically, using the anti-inflammatory dosages established in other species. These drugs are used most appropriately for the management of the allergies that we suspect occur in this species, until better alternative therapies can be developed. Variably pruritic focal areas of alopecia, exudation, and crusting suggest differential diagnoses including bacterial folliculitis and furunculosis, dermatophilosis, dermatophytosis, and coccidioimycosis. The diagnosis of bacterial problems often is made by assessing response to antibiotic therapy. Topical disinfectants and/or systemic penicillin or trimethoprim-sulfadiazine are indicated. Dermatophilosis is treated by cle

15. Aust J Biol Sci. 1978 Apr;31(2):161-72. doi: 10.1071/bi9780161. Effects of abomasal supplements of methionine on the wool follicles and skin of wheat-fed sheep. Chapman RE, Reis PJ. In wheat-fed sheep, supplemented abomasally with 1.5-6.0 g methionine per day, poor formation and improper keratinization of the wool fibres were evident 4 days after the start of the methionine supplementation. This led to kinking of the fibres. Subsequently severe distortion of the fibres, accompanied by gross thickening of the outer root sheaths, occurred in the distal (upper) halves of most follicles. Within this thickened region partial degradation of the distorted fibres occurred before emergence from the skin surface, causing a marked reduction in the tensile strength of the wool. It is postulated that kinking of the fibres stimulated the accumulation of outer root sheath cells, which led to hyperactivity of the process that normally degrades the inner root sheath, so that the poorly keratinized fibres were also partly degraded. Thickening of the epidermis and cellular infiltration of the upper dermis sometimes occurred during the infusions of methionine, whereas there were negligible effects on the sebaceous and sweat glands. Disappearance of the excess accumulation of outer root sheath cells after cessation of the methionine supplementation occurred gradually following improvement in keratinization and elimination of kinking of the fibres.