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Concept: Baldness

275

Male pattern baldness can have substantial psychosocial effects, and it has been phenotypically linked to adverse health outcomes such as prostate cancer and cardiovascular disease. We explored the genetic architecture of the trait using data from over 52,000 male participants of UK Biobank, aged 40-69 years. We identified over 250 independent genetic loci associated with severe hair loss (P<5x10-8). By splitting the cohort into a discovery sample of 40,000 and target sample of 12,000, we developed a prediction algorithm based entirely on common genetic variants that discriminated (AUC = 0.78, sensitivity = 0.74, specificity = 0.69, PPV = 59%, NPV = 82%) those with no hair loss from those with severe hair loss. The results of this study might help identify those at greatest risk of hair loss, and also potential genetic targets for intervention.

Concepts: Epidemiology, Cancer, Prostate cancer, Alopecia, Baldness, Androgenic alopecia, Baldness treatments, Minoxidil

167

Alopecia areata (AA) is a common autoimmune disorder mostly presented as round patches of hair loss and subclassified into alopecia totalis/alopecia universalis (AT/AU) based on the area of alopecia. Although AA is relatively common, only 5% of AA patients progress to AT/AU, which affect the whole scalp and whole body respectively. To determine genetic determinants of this orphan disease, we undertook whole-exome sequencing of 6 samples from AU patients, and 26 variants in immune-related genes were selected as candidates. When an additional 14 AU samples were genotyped for these candidates, 6 of them remained at the level of significance in comparison with 155 Asian controls (p<1.92×10(-3)). Linkage disequilibrium was observed between some of the most significant SNPs, including rs41559420 of HLA-DRB5 (p<0.001, OR 44.57) and rs28362679 of BTNL2 (p<0.001, OR 30.21). While BTNL2 was reported as a general susceptibility gene of AA previously, HLA-DRB5 has not been implicated in AA. In addition, we found several genetic variants in novel genes (HLA-DMB, TLR1, and PMS2) and discovered an additional locus on HLA-A, a known susceptibility gene of AA. This study provides further evidence for the association of previously reported genes with AA and novel findings such as HLA-DRB5, which might represent a hidden culprit gene for AU.

Concepts: DNA, Gene, Genetics, Genetic linkage, Autoimmune diseases, Locus, Baldness, Alopecia areata

160

Various trials have been conducted on the management and treatment of androgenic alopecia (AGA) or male pattern hair loss using a variety of laser and light sources.

Concepts: Light, Laser, 2000s music groups, Alopecia, Baldness, Androgenic alopecia, Treat Williams

96

To confirm the association between male pattern baldness and coronary heart disease (CHD).

Concepts: Alopecia, Baldness

28

BACKGROUND: Androgenetic alopecia (AGA) is a genetically determined skin condition strongly age dependent and androgens are assumed to play an important role in its development. A link between AGA and prostate cancer has been hypothesized because of their similar risk factors. OBJECTIVE: We sought to systematically review the evidence available on the association between AGA and risk of prostate cancer. METHODS: We searched the electronic databases MEDLINE and Cochrane for studies examining the association between AGA and risk of prostate cancer. We estimated pooled odds ratios (OR) and 95% confidence intervals. We also analyzed the OR for individual hair loss patterns, as defined by the Hamilton scale. RESULTS: A total of 7 case-control studies including 8994 patients-4078 cases and 4916 controls-were reviewed. One cohort study was identified but did not meet our inclusion criteria. There was statistically significant association between vertex baldness and prostate cancer (OR 1.25; 95% confidence interval 1.09-1.44; Z = 3.13; P = .002). No statistically significant association between AGA (any pattern) and prostate cancer was identified (OR 1.03; 95% confidence interval 0.93-1.13; Z = 0.55; P = .58). LIMITATIONS: Only case-control studies, which may be subject to bias, met the inclusion criteria for this meta-analysis. CONCLUSIONS: Vertex pattern AGA was associated with a significant increased risk of prostate cancer. Any pattern AGA did not show a significant increase in the risk of prostate cancer.

Concepts: Epidemiology, Statistics, Prostate cancer, Confidence interval, Statistical hypothesis testing, Alopecia, Baldness, Androgenic alopecia

28

The characteristic lesion of alopecia areata is a smooth bald patch on the scalp. When there is no bald surface it is called alopecia areata incognita. To date, all cases of alopecia areata reported as so-called ‘incognito’ have shown a diffuse involvement of the scalp as in acute telogen effluvium. Recently, we have observed two patients who showed localised hair thinning of the scalp without bald spots. Histopathologically, the lesions were typical of alopecia areata with peribulbar lymphocytic infiltrates. The response to corticosteroid treatment and its clinical course were also compatible with alopecia areata.

Concepts: Anatomical pathology, Corticosteroid, Ablative brain surgery, Lesion, Baldness, Alopecia areata, Conditions of the skin appendages, Telogen effluvium

28

Alopecia areata (AA) is a common acquired hair disorder showing variable hair loss. Although various prognostic factors have been reported, no evident factors for determining prognosis and appropriate treatment are known.

Concepts: Medical terms, Baldness, Alopecia areata

27

Introduction: Androgenetic alopecia (AGA) is the most common form of hair loss, however current treatment options are limited and moderately effective. In the past few years, there has been an increased interest in deciphering the molecular mechanisms responsible for this disorder, which has opened the possibility of novel treatments that promise to not only stimulate hair growth, but also to induce formation of new hair follicles. Areas covered: The future holds more effective topical treatments with less systemic side effects (such as topical 5-alfa-reductase inhibitors), prostaglandin analogs and antagonists, medications which act through the Wnt signaling pathway, stem cells for hair regeneration, platelet-rich plasma (PRP) and more effective ways of transplanting hair. A comprehensive search was made using PubMed, GoogleScholar and Clinicaltrial.gov using different combination of key words, which included AGA treatment, new treatments for AGA, Wnt pathway, prostaglandins, PRP and stem cells for hair regrowth. Expert opinion: In the near future, treatments with topical 5-alfa-reductase inhibitors and prostaglandin agonists or antagonists are expected. More evidence is needed to verify the efficacy of PRP. Although hair follicle bioengineering and multiplication is a fascinating and promising field, it is still a long way from being available to clinicians.

Concepts: Protein, Pharmacology, Chemotherapy, Hair, Wnt signaling pathway, Alopecia, Baldness, Androgenic alopecia

27

X-Linked ichthyosis (XRI) is a keratinisation disorder caused by a mutation of the steroid sulfatase gene. An association with mental retardation and epilepsy has been reported earlier. Here, we report on a patient suffering from cerebellar symptoms such as yes/yes head tremor, scanning dysarthria, pronounced dysmetria and intention tremor, without any abnormalities of the cerebellum in MRI, in addition to XRI proven by molecular genetics. Furthermore, the patient suffered from anxiety disorder, depression, and a male pattern baldness. One of the patient' s brothers and a nephew showed a similar clinical presentation. Because of the fact that several members of the patient´s family suffered from similar symptoms, we consider a syndromic link between XRI and cerebellar disorder to be possible.

Concepts: DNA, Genetics, Ataxia, Alopecia, Baldness, Androgenic alopecia, X-linked ichthyosis

25

Abstract Context: Chrysanthemum zawadskii var. latilobum (Asteraceae) (CZ) and Polygonum multiflorum Thunb. (Polygonaceae) (PM) have been used traditionally to treat different systemic diseases and acclaimed for various biological activities including hair growth. Objective: This study investigates the hair restoration efficacy of selected medicinal plant extracts on nude mice. Materials and methods: Nude mice genetically predisposed to pattern balding were used in this study. Topical methanol extracts of CZ and PM (10 mg/mouse/d) with standardized vehicle formulation, only vehicle (propylene glycol:ethanol:dimethyl sulfoxide, 67:30:3% v/v) and Minoxidil (2%) were applied daily for 40 consecutive days. Results: In our study, the maximum hair score (2.5 ± 0.29) was obtained in the CZ-treated group. Histological observation revealed a significant increase (p < 0.001) in the number of hair follicles (HF) in CZ-treated mice (58.66 ± 3.72) and Minoxidil-treated mice (40 ± 2.71). Subsequently, immunohistochemical analysis also confirmed the follicular keratinocyte proliferation by detection of BrdU-labeling, S-phase cells in Minoxidil and CZ-treated mouse follicular bulb and outer root sheaths. Conclusion: Our study revealed the underlying mechanism of stimulating hair growth in athymic nude mice by repair the nu/nu follicular keratin differentiation defect. Thus, the topical application of CZ may represent a novel strategy for the management and therapy of certain forms of alopecia.

Concepts: Histology, Baldness, Androgenic alopecia, Chrysanthemum, Polygonum multiflorum, Nude mouse, Polygonum, Plant extract