Role of adiponectin and leptin in patients with alopecia areata with scalp hair loss

Adiponectin serum levels and ADIPOQ (rs2241766) polymorphism in alopecia areata Egyptian patients

BACKGROUND

Alopecia Areata (AA) is an acquired autoimmune form of non-scarring hair loss. Adiponectin and its gene polymorphism were related to many autoimmune disorders.

OBJECTIVE

Assessment of adiponectin serum levels and adiponectin gene (ADIPOQ) (rs2241766) Single Nucleoid Polymorphism (SNP) in AA patients and correlating the results with the disease severity in those patients.

METHODS

This study included 75 AA patients and 75 age and gender-matched healthy subjects (controls). The severity of Alopecia Tool (SALT) score assessment to evaluate AA severity was done. Adiponectin serum levels by ELISA and ADIPOQ (rs2241766) SNP using PCR were performed.

RESULTS

Adiponectin serum levels were significantly lower in AA patients than controls (p = 0.001). ADIPOQ (rs2241766) TG genotype and G allele were significantly predominant in AA patients increasing its risk by 5 and 4 folds (OR = 5.17, p = 0.001), (OR = 3.82, p = 0.001) respectively. Serum adiponectin levels were negatively correlated with SALT score (r = -0.435, p = 0.001) and associated with alopecia totalis (p = 0.016). ADIPOQ (rs2241766) TG genotype was significantly associated with low serum adiponectin levels and higher SALT score (p = 0.001).

STUDY LIMITATIONS

The small sample size.

CONCLUSIONS

ADIPOQ (rs2241766) gene polymorphism (TG genotype and G allele) may modulate AA risk and contribute to the development of AA in Egyptian populations. Decreased circulating adiponectin levels may have a dynamic role in AA etiopathogenesis. Adiponectin serum concentration can be considered a severity marker of hair loss in AA.

Association of Obesity and Bariatric Surgery on Hair Health

Obesity and obesity-related conditions today constitute a public health problem worldwide. Obesity is an "epidemic" chronic disorder, which is defined by the WHO as normal or excessive fat accumulation that may impair health. It is also defined for adults as a BMI that is greater than or equal to 30. The most common obesity-related diseases are type 2 diabetes mellitus, cardiovascular diseases, metabolic syndrome, chronic kidney disease, hyperlipidemia, hypertension, nonalcoholic fatty liver disease, and certain types of cancer. It has been also proven that obesity can have a negative effect on hair. It can lead to hair thinning. Patients with obesity can undergo bariatric surgery if they meet the inclusion criteria. The four common types of weight loss surgery include a duodenal switch with biliopancreatic diversion, laparoscopic adjustable gastric banding, Roux-en-Y gastric bypass, and sleeve gastrectomy. Bariatric surgery can affect skin and hair and is associated with telogen effluvium due to weight loss, microelement deficiency, anesthesia, low calorie intake, and low protein intake. Patients who undergo bariatric surgery can experience post-bariatric surgery depression. Hair loss can have a major impact on self-esteem, negatively affecting one's self-image. The purpose of this narrative review is to critically review how obesity, obesity-related diseases, and bariatric surgery affect hair health in general and the hair development cycle, and how they influence hair loss.

Feasibility of adipose-derived therapies for hair regeneration: Insights based on signaling interplay and clinical overview

Dermal white adipose tissue (dWAT) is a dynamic component of the skin and closely interacts with the hair follicle. Interestingly, dWAT envelops the hair follicle during anagen and undergoes fluctuations in volume throughout the hair cycle. dWAT-derived extracellular vesicles can significantly regulate the hair cycle, and this provides a theoretical basis for utilizing adipose tissue as a feasible clinical strategy to treat hair loss. However, the amount and depth of the available literature are far from enough to fully elucidate the prominent role of dWAT in modulating the hair growth cycle. This review starts by investigating the hair cycle-coupled dWAT remodeling and the reciprocal signaling interplay underneath. Then, it summarizes the current literature and assesses the advantages and limitations of clinical research utilizing adipose-derived therapies for hair regeneration.

Leptin deficiency in CD8+ T cells ameliorates non-segmental vitiligo by reducing interferon-γ and Granzyme B

Background

Vitiligo is an autoimmune skin disease mainly mediated by CD8⁺ T cells, which affects about 0.1%-2% population of the world. Leptin plays a critical role in regulating the activation of CD8⁺ T cells. However, the effect of Leptin on vitiligo remains unclear.

Objectives

To explore the effect of leptin on CD8⁺ T cells and its influence on vitiligo.

Methods

RNA sequencing and Quantitative Real-time PCR (RT-qPCR) were used to explore the differentially expressed genes. Immunofluorescence staining was performed on skin lesions. Leptin in serum was detected by enzyme linked immunosorbent assay (ELISA). The peripheral blood mononuclear cells were detected by flow cytometry after leptin stimulation for 72 hours. A vitiligo model was established by monobenzone on Leptin KO mice.

Results

557 differentially expressed genes were found, including 154 up-regulated and 403 down-regulated genes. Lipid metabolism pathways showed a close relationship to the pathogenesis of vitiligo, especially the PPAR signaling pathway. RT-qPCR (p = 0.013) and immunofluorescence staining (p = 0.0053) verified that LEPR expressed significantly higher in vitiligo. The serum leptin level of vitiligo patients was significantly lower than that of healthy controls (p = 0.0245). The interferon-γ subset of CD8⁺LEPR⁺ T cells from vitiligo patients was significantly higher (p = 0.0189). The protein level of interferon-γ was significantly increased after leptin stimulation in vitro (p = 0.0217). In mice, Leptin deficiency resulted in less severe hair depigmentation. Leptin deficiency also resulted in significantly lower expressed vitiligo-related genes, such as Cxcl9 (p = 0.0497), Gzmb (p < 0.001), Ifng (p = 0.0159), and Mx1 (p < 0.001) after modeling.

Conclusion

Leptin could promote the progression of vitiligo by enhancing the cytotoxic function of CD8⁺ T cells. Leptin may become a new target for vitiligo treatment.

Study of leptin gene polymorphism and leptin serum level in alopecia areata patients

Leptin, produced by adipocytes, regulates metabolism, hunger, and immune response. The inflammatory role of leptin has been linked to autoimmune diseases. To assess leptin gene polymorphism and serum level in alopecia areata and their relation to metabolic syndrome (MS). This case-control study was conducted on 100 alopecia areata patients (50 with MS and 50 without MS) and 50 age- and gender-matched controls. Leptin gene polymorphism and serum level were assessed through the use of PCR and ELISA, respectively. GG genotype was the highest in AA with MS (54%), lower in AA without MS (42%), and the lowest in controls (20%). G allele was more expressed in cases, than in controls (P < .001). The serum leptin level was the highest in AA with MS, lower in AA without MS, and the lowest in controls (P value = 0.001). Leptin level was significantly higher in GG polymorphism than AG and AA. Leptin gene polymorphism (GG genotype) and serum level appear to play a significant role in AA. Absent difference regarding leptin gene polymorphism and MS might indicate a separate inflammatory role of leptin or the future risk of MS development in AA patients.

Lifestyle Factors Involved in the Pathogenesis of Alopecia Areata

Alopecia areata is a representative inflammatory skin disease that is associated with various environmental stimuli. While psychological stress is believed to be a major pathogenetic trigger in alopecia areata, infants and newborns also suffer from the disease, suggesting the possible presence of other environmental factors. Daily lifestyle is well known to be involved in various inflammatory diseases and influences the severity of inflammatory skin diseases. However, only a limited number of studies have summarized these influences on alopecia areata. In this review article, we summarize lifestyle factor-related influences on the pathogenesis of alopecia areata and focus on environmental factors, such as smoking, alcohol consumption, sleep, obesity, fatty acids, and gluten consumption.

Adiponectin as a novel biomarker of disease severity in alopecia areata

The frequent coexistence of obesity and metabolic syndrome in patients with alopecia areata may indicate the common pathogenetic pathway in these conditions with an important role of adipokines. The aim of the study was to evaluate the serum level of adiponectin, resistin and leptin in patients with alopecia areata in comparison to healthy controls. The study included 65 patients with alopecia areata and 71 healthy controls. The concentration of adipokines was determined with the enzyme-linked immunosorbent assay. The mean concentrations of adiponectin and resistin were significantly lower in the sera of patients with alopecia areata when compared to healthy controls (7966 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\pm$$\end{document}± 4087 vs 9947 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\pm$$\end{document}± 5692 ng/ml; p = 0.0312 and 11.04 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\pm$$\end{document}± 3.88 vs 14.11 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\pm$$\end{document}± 8.69 ng/ml; p = 0.0176, respectively). A negative correlation between the serum level of adiponectin and severity of alopecia tool (SALT) score was observed (r = − 0.26; p < 0.05). The concentration of adiponectin was significantly lower in patients with alopecia universalis than in patients with patchy alopecia areata (4951 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\pm$$\end{document}± 2499 vs 8525 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\pm$$\end{document}± 4085 ng/ml; p = 0.0135). No significant difference in the serum concentration of leptin was observed between patients with alopecia areata and healthy controls. The negative correlation between the serum level of adiponectin and hair loss severity indicates that adiponectin may be considered a marker of hair loss severity in alopecia areata. Further studies are needed to evaluate the role of resistin in patients with alopecia areata and its decreased level irregardless of severity or activity of the disease.