A G Messenger

University of Bonn, Bonn, North Rhine-Westphalia, Germany

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Publications (128)560.1 Total impact

  • A G Messenger
    British Journal of Dermatology 03/2014; 170(3):493-4. · 3.76 Impact Factor
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    ABSTRACT: Female pattern hair loss (FPHL) is a common hair loss disorder in women and has a complex mode of inheritance. The etiopathogenesis of FPHL is largely unknown; however, it is hypothesized that FPHL and male pattern baldness [androgenetic alopecia (AGA)] share common genetic susceptibility alleles. Our recent findings indicate that the major AGA locus, an X-chromosome region containing the androgen receptor and the ectodysplasin A2 receptor (EDA2R) genes, may represent a common genetic factor underlying both early-onset FPHL and AGA. This gives further support for the widespread assumption of shared susceptibility loci for FPHL and AGA. However, we could not demonstrate association of further AGA risk loci, including 20p11, 1p36.22, 2q37.3, 7p21.1, 7q11.22, 17q21.31, and 18q21.1, with FPHL. Interestingly, a recent study identified four novel AGA risk loci in chromosomal regions 2q35, 3q25.1, 5q33.3, and 12p12.1. In particular, the 2q35 locus and its gene WNT10A point to an as-yet unknown involvement of the WNT signaling pathway in AGA. We hypothesized that the novel loci and thus also the WNT signaling may have a role in the etiopathogenesis of FPHL and therefore examined the role of these novel AGA risk loci in our FPHL samples comprising 440 German and 145 UK affected patients, 500 German unselected controls (blood donors), and 179 UK supercontrols. Patients and controls were genotyped for the top two single nucleotide polymorphisms at each of the four AGA loci. However, none of the genotyped variants displayed any significant association. In conclusion, the results of this study provide no support for the hypothesis that the novel AGA loci influence susceptibility to FPHL.
    Archives for Dermatological Research 12/2013; · 2.71 Impact Factor
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    ABSTRACT: The aetiopathogenesis of female pattern hair loss (FPHL) is poorly understood. Although research has strongly implicated genetic factors in familial occurrence, no association finding for FPHL has yet been replicated. Consequently, no causal biological pathways can be suggested on the basis of currently available genetic findings. A recent gene-wide association study of ESR2 (oestrogen receptor 2) investigated 32 tag SNPs in an Australian FPHL sample, and found nominal significance for three variants (rs10137185, rs17101774, rs202274). This article is protected by copyright. All rights reserved.
    British Journal of Dermatology 12/2013; · 3.76 Impact Factor
  • Journal of dermatological science 07/2013; · 3.71 Impact Factor
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    ABSTRACT: Despite an increasing knowledge of dandruff and se-borrheic dermatitis (D/SD), the pathophysiological understanding is still incomplete but suggests a role of Malassezia yeasts in triggering inflammatory and hy-per-proliferative epidermal responses. The objective of this report is to review published literature from in vivo studies of D/SD populations to provide a more complete description of overall scalp health. New biomolecular capabilities establish a depth of pathophysiological un-derstanding not previously achievable with traditional means of investigation. Biomarkers representing inflam-mation, hyper-proliferation and barrier function are all perturbed by the D/SD condition and robustly re-spond to therapeutic resolution. These biomarkers can be sampled noninvasively, enabling their use in routine clinical evaluations as either surrogate endpoints or com-plementary ones to classical signs/symptoms to broaden the etiological learning. Key words: dandruff; seborrheic dermatitis; inflammation; hyper-proliferation; skin bar-rier; biomarkers; scalp health. Accepted Mar 12, 2012; Epub ahead of print Aug 8, 2012 Acta Derm Venereol 2013; 93: 131–137. Dandruff and seborrheic dermatitis (D/SD) are common afflictions of the human scalp (1) and considered the same basic condition differing only in magnitude (2). Heredity plays only a small role in developing a predisposition for the condition (3). A comprehensive review of the pathop-hysiological changes in the stratum corneum (SC) in these conditions at the macro (signs and symptoms), micro (phy-siological structure and function) and biomolecular strata may enable a precise and more complete determination of the condition of the scalp and also the therapeutic responses to treatment leading to restoration of homeostasis. A more complete description of the pathophysiology of the D/SD condition results from combining these 3 informational strata. This combination can lead to a paradigm shift in describing what constitutes a return to "scalp health." A more comprehensive description of "scalp health" incorporating new biomolecular markers in addition to the existing clinical parameters has several benefits: (i) Advan-ces the understanding of the biopathology of the condition; (ii) Provides a framework to assess the thoroughness of therapies; (iii) Enables the use of other clinical endpoints in addition to the commonly observed signs and symp-toms; and (iv) Establishes relevant sub-clinical parameters that can supplement clinical observations. In order to discuss the characteristic structural and biomolecular abnormalities associated with D/SD, it is convenient to categorize them by the following 4 sequential pathophysiological phases (4): • Malassezia ecosystem and interaction with the epidermis; • Initiation and propagation of inflammation; • Disruption of proliferation and differentiation processes of the epidermis; and • Physical and functional skin barrier disruption. Each pathophysiological phase can then be considered sequentially at the 3 informational strata, progressing from macro to micro perspective, viz. Symptoms and signs; Structure and function, and Biomolecular changes, focusing almost exclusively on in vivo observations on D/SD populations to assure the relevance to the clinical condition (see supplementary Appendix for Material and Methods; available from http://www.medicaljournals.se/ acta/content/?doi=10.2340/00015555-1382). The 4 pathophysiological phases and the 3 informational strata can be considered orthogonal views of the total D/ SD data. By combining these views, an organizational model emerges (Fig. 1) which allows each independent measure to be categorized by its pathophysiological phase and informational stratum. This categorization facilitates the comparison of measures within a given phase and across the strata or vice versa. A more complete model of scalp health emerges, including the circular nature of the pathophysiology, in which decreased barrier integrity increases further susceptibility. In this review, each informational stratum will be co-vered sequentially, starting with the macro level observa-tions and finishing at the foundational biomolecular level,
    Acta Dermato Venereologica 01/2013; 93(2):131-137. · 3.49 Impact Factor
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    ABSTRACT: Female pattern hair loss (FPHL) is a common hair loss disorder in women with a complex mode of inheritance. Its etiopathogenesis is poorly understood. Widespread assumptions of overlapping susceptibility variants between FPHL and male pattern baldness (androgenetic alopecia) and a crucial role of androgens or distinct sexual steroid hormones in the development of FPHL could neither be clearly demonstrated nor completely excluded at the molecular level up to date. Interestingly, recent studies suggested an association of metabolic syndrome-including obesity, hyperlipidaemia, hypertension and diabetes mellitus type 2 or abnormally high fasting blood glucose-with FPHL. Of note, mutations in the melanocortin 4 receptor gene (MC4R) have been identified in patients with morbid obesity. Interestingly, this neuropeptide receptor has been detected amongst others in the dermal papilla of the hair follicle. As almost half of our FPHL patients of German origin present with adipositas and/or obesity, we hypothesized as to whether FPHL could be associated with variants of the MC4R gene. Thus, we genotyped a total of six variants from MC4R in our case-control sample comprising 245 UK patients of German and UK origin. However, based on our present study none of the genotyped MC4R variants displayed any significant association, neither in the overall UK and German samples nor in any subgroup analyses. In summary, these results do not point to an involvement of MC4R in FPHL.
    Archives for Dermatological Research 11/2012; · 2.71 Impact Factor
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    [Show abstract] [Hide abstract]
    ABSTRACT: Despite an increasing knowledge of dandruff and seborrheic dermatitis (D/SD), the pathophysiological understanding is still incomplete but suggests a role of Malassezia yeasts in triggering inflammatory and hyper-proliferative epidermal responses. The objective of this report is to review published literature from in vivo studies of D/SD populations to provide a more complete description of overall scalp health. New biomolecular capabilities establish a depth of pathophysiological understanding not previously achievable with traditional means of investigation. Biomarkers representing inflammation, hyper-proliferation and barrier function are all perturbed by the D/SD condition and robustly respond to therapeutic resolution. These biomarkers can be sampled noninvasively, enabling their use in routine clinical evaluations as either surrogate endpoints or complementary ones to classical signs/symptoms to broaden the etiological learning.
    Acta Dermato-Venereologica 08/2012;
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    British Journal of Dermatology 05/2012; 166(5):916-26. · 3.76 Impact Factor
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    ABSTRACT: Female pattern hair loss (FPHL) is a common disorder with a complex mode of inheritance. Although understanding of its etiopathogenesis is incomplete, an interaction between genetic and hormonal factors is assumed to be important. The involvement of an androgen-dependent pathway and sex steroid hormones is the most likely hypothesis. We therefore selected a total of 21 variants from the steroid-5-alpha-reductase isoforms SRD5A1 and SRD5A2, the sex steroid hormone receptors ESR1, ESR2 (oestrogen receptor) and PGR (progesterone receptor) and genotyped these in a case-control sample of 198 patients (145 UK; 53 German patients) and 329 controls (179 UK; 150 German). None of these variants showed any significant association, either in the overall UK and German samples or in the subgroup analyses. In summary, the present results, while based on a limited selection of gene variants, do not point to the involvement of SRD5A1, SRD5A2, ESR1, ESR2 or PGR in FPHL.
    Experimental Dermatology 05/2012; 21(5):390-3. · 3.58 Impact Factor
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    ABSTRACT: It has long been known that women lose satisfaction with their hair with ageing. Our data show that caucasian women perceive a decrease in hair amount in their mid 40s with a further decrease in the mid to late 50s, which leads to this dissatisfaction. Neither loss of density (hairs per cm(2) ) nor shaft diameter alone can fully account for this perception. A new metric, 'hair amount', is proposed as a quantitative metric combining the impact of both density and diameter on the perception of hair loss. Creation of a single parameter combining the contribution of diameter and density to perception of female age-related hair loss. In total, 1099 caucasian women (ages 18-66 years) with self-perceived hair loss and 315 caucasian women (ages 17-86 years) with no complaint of hair loss were evaluated. Scalp hair diameter was measured using optical fibre diameter and image analysis. Scalp hair density was measured by phototrichogram with manual or automated counting. Parietal scalp hair diameter increased from ages 20 to 40-45 years, then decreased. Hair density was highest in the youngest group, age 20-30 years, and decreased thereafter with increasing rate. In women self-perceiving hair loss, the rate of decrease in density was significantly faster than for women with no self-perception of hair loss. The combined metric 'hair amount' was relatively constant at younger ages, increasing very slightly to age 35 years, then decreasing significantly. Increasing hair shaft diameter offsets decreasing hair density through the mid 30s. After that, a lower rate of diameter increase combined with the decrease in density begins to significantly impact the perception of hair amount so that thinning becomes increasingly more noticeable in the mid 40s to the mid to late 50s. Quantitative determination of hair amount is a useful tool to combine the contributions of hair density and diameter to women's perception of age-related hair loss.
    British Journal of Dermatology 04/2012; 167(2):324-32. · 3.76 Impact Factor
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    ABSTRACT: The aetiology of female pattern hair loss (FPHL) is largely unknown. However, it is hypothesized that FPHL and male pattern baldness (AGA) share common susceptibility alleles. The two major susceptibility loci for AGA are the androgen receptor (AR)/ectodysplasin A2 receptor (EDA2R) locus on the X-chromosome, and a locus on chromosome 20p11, for which no candidate gene has yet been identified. To examine the role of the AR/EDA2R and 20p11 loci in the development of FPHL using 145 U.K. and 85 German patients with FPHL, 179 U.K. supercontrols and 150 German blood donors. Patients and controls were genotyped for 25 single nucleotide polymorphisms (SNPs) at the AR/EDA2R locus and five SNPs at the 20p11 locus. Analysis of the AR/EDA2R locus revealed no significant association in the German sample. However, a nominally significant association for a single SNP (rs1397631) was found in the U.K. sample. Subgroup analysis of the U.K. patients revealed significant association for seven markers in patients with an early onset (P = 0·047 after adjustment for the testing of multiple SNPs by Monte Carlo simulation). No significant association was obtained for the five 20p11 variants, either in the overall samples or in the analysis of subgroups. The observed association suggests that the AR/EDA2R locus confers susceptibility to early-onset FHPL. Our results do not implicate the 20p11 locus in the aetiology of FPHL.
    British Journal of Dermatology 02/2012; 166(6):1314-8. · 3.76 Impact Factor
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    ABSTRACT: Background Androgens are thought to have an adverse effect on female scalp hair growth. However, our clinical experience of androgen replacement therapy in women with androgen deficiency, in which hair loss was seldom reported, led us to question this concept. Objectives To evaluate the effect of subcutaneous testosterone therapy on scalp hair growth in female patients. Methods A total of 285 women, treated for a minimum of 1 year with subcutane-ous testosterone implants for symptoms of androgen deficiency, were asked to complete a survey that included questions on scalp and facial hair. Age, body mass index (BMI) and serum testosterone levels were examined. Results Out of the 285 patients, 76 (27%) reported hair thinning prior to treat-ment; 48 of these patients (63%) reported hair regrowth on testosterone therapy (responders). Nonresponders (i.e. no reported hair regrowth on therapy) had significantly higher BMIs than responders (P = 0AE05). Baseline serum testosterone levels were significantly lower in women reporting hair loss prior to therapy than in those who did not (P = 0AE0001). There was no significant difference in serum testosterone levels, measured 4 weeks after testosterone implantation, between responders and nonresponders. No patient in this cohort reported scalp hair loss on testosterone therapy. A total of 262 women (92%) reported some increase in facial hair growth. Conclusions Subcutaneous testosterone therapy was found to have a beneficial effect on scalp hair growth in female patients treated for symptoms of androgen defi-ciency. We propose this is due to an anabolic effect of testosterone on hair growth. The fact that no subject complained of hair loss as a result of treatment casts doubt on the presumed role of testosterone in driving female scalp hair loss. These results need to be confirmed by formal measurements of hair growth.
  • A G Messenger
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    ABSTRACT: At a population level female scalp hair growth shows features of regression with chronological ageing, although there is wide interindividual variation in timing and degree. The subjective assessment of hair loss is classically determined by hair density but it is apparent that other factors contribute to the clinical picture. Changes can occur in hair cycling, hair density, hair diameter and pigmentation, and possibly in structural qualities of the hair fibre. These changes are most pronounced in female pattern hair loss. Although conventionally considered as the female counterpart of male androgenetic alopecia the evidence that female pattern hair loss is androgen dependent is less clear cut than in men and it probably has a multifactorial basis. The emerging evidence implicating environmental factors is of particular interest as, unlike genes, such factors may be amenable to intervention. The clinical signs in women complaining of hair loss may be variable. In evaluating the patient complaining of hair loss, while true pathology must always be considered, the clinician needs to be aware of how age affects hair growth. These changes form the focus of this article.
    British Journal of Dermatology 12/2011; 165 Suppl 3:2-6. · 3.76 Impact Factor
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    R L Glaser, C Dimitrakakis, A G Messenger
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    ABSTRACT: Androgens are thought to have an adverse effect on female scalp hair growth. However, our clinical experience of androgen replacement therapy in women with androgen deficiency, in which hair loss was seldom reported, led us to question this concept. To evaluate the effect of subcutaneous testosterone therapy on scalp hair growth in female patients. A total of 285 women, treated for a minimum of 1year with subcutaneous testosterone implants for symptoms of androgen deficiency, were asked to complete a survey that included questions on scalp and facial hair. Age, body mass index (BMI) and serum testosterone levels were examined. Out of the 285 patients, 76 (27%) reported hair thinning prior to treatment; 48 of these patients (63%) reported hair regrowth on testosterone therapy (responders). Nonresponders (i.e. no reported hair regrowth on therapy) had significantly higher BMIs than responders (P=0·05). Baseline serum testosterone levels were significantly lower in women reporting hair loss prior to therapy than in those who did not (P=0·0001). There was no significant difference in serum testosterone levels, measured 4weeks after testosterone implantation, between responders and nonresponders. No patient in this cohort reported scalp hair loss on testosterone therapy. A total of 262 women (92%) reported some increase in facial hair growth. Subcutaneous testosterone therapy was found to have a beneficial effect on scalp hair growth in female patients treated for symptoms of androgen deficiency. We propose this is due to an anabolic effect of testosterone on hair growth. The fact that no subject complained of hair loss as a result of treatment casts doubt on the presumed role of testosterone in driving female scalp hair loss. These results need to be confirmed by formal measurements of hair growth.
    British Journal of Dermatology 10/2011; 166(2):274-8. · 3.76 Impact Factor
  • A G Messenger
    British Journal of Dermatology 10/2011; 165 Suppl 2:1. · 3.76 Impact Factor
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    ABSTRACT: Androgenetic alopecia is the most common hair loss disorder, affecting both men and women. Initial signs of androgenetic alopecia usually develop during teenage years leading to progressive hair loss with a pattern distribution. Moreover, its frequency increases with age and affects up to 80 % Caucasian men and 42 % of women. Patients diagnosed with androgenetic alopecia may undergo significant impairment of quality of life. Despite the high prevalence and the variety of therapeutic options available, there have been no national or international evidence-based guidelines for the treatment of androgenetic alopecia in men and women so far. Therefore, the European Dermatology Forum (EDF) initiated a project to develop an evidence-based S3 guideline for the treatment of andro-genetic alopecia. Based on a systematic literature research the efficacy of the currently available therapeutic options was assessed and therapeutic recommendations were passed in a consensus conference. The purpose of the guideline is to provide dermatologists as well as general practitioners with an evidence-based tool for choosing an efficacious and safe therapy for patients with androgenetic alopecia.
    Journal der Deutschen Dermatologischen Gesellschaft 10/2011; 9 Suppl 6:S1-57. · 1.40 Impact Factor
  • British Journal of Dermatology 06/2011; 165(3):703-5. · 3.76 Impact Factor
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    ABSTRACT: Allergic contact dermatitis in children is less recognized than in adults. However, recently, allergic contact dermatitis has started to attract more interest as a cause of or contributor to eczema in children, and patch testing has been gaining in recognition as a useful diagnostic tool in this group. The aim of this analysis was to investigate the results of patch testing of selected children with eczema of various types (mostly atopic dermatitis) attending the Sheffield Children's Hospital, and to assess potential allergens that might elicit allergic contact dermatitis. We analysed retrospectively the patch test results in 110 children aged between 2 and 18 years, referred to a contact dermatitis clinic between April 2002 and December 2008. We looked at the percentages of relevant positive reactions in boys and girls, by age groups, and recorded the outcome of treatment following patch testing. One or more positive allergic reactions of current or past relevance was found in 48/110 children (44%; 29 females and 19 males). There were 94 allergy-positive patch test reactions in 110 patients: 81 had a reaction of current or past relevance, 12 had a reaction of unknown relevance, and 1 had reaction that was a cross-reaction. The commonest allergens with present or past relevance were medicaments, plant allergens, house dust mite, nickel, Amerchol® L101 (a lanolin derivative), and 2-bromo-2-nitropropane-1,3-diol. However, finding a positive allergen was not associated with a better clinical outcome. We have shown that patch testing can identify relevant allergens in 44% of children with eczema. The commonest relevant allergens were medicament allergens, plant allergens, house dust mite, nickel, Amerchol® L101, and 2-bromo-2-nitropropane-1,3-diol. Patch testing can be performed in children as young as 2 years with the proper preparation.
    Contact Dermatitis 04/2011; 65(4):208-12. · 2.93 Impact Factor
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    ABSTRACT: Androgenetic alopecia (AGA) is the most common hair loss disorder, affecting both men and women. Due to the frequency and the often significant impairment of life perceived by the affected patients, competent advice, diagnosis and treatment is particularly important. As evidence-based guidelines on hair disorders are rare, a European consensus group was constituted to develop guidelines for the diagnostic evaluation and treatment of AGA. This S1 guideline for diagnostic evaluation of AGA in men, women and adolescents reviews the definition of AGA and presents expert opinion-based recommendations for sex-dependent steps in the diagnostic procedure.
    British Journal of Dermatology 01/2011; 164(1):5-15. · 3.76 Impact Factor
  • P Cousen, A Messenger
    British Journal of Dermatology 11/2010; 163(5):1141-2. · 3.76 Impact Factor

Publication Stats

3k Citations
560.10 Total Impact Points

Institutions

  • 2012–2013
    • University of Bonn
      • Institute of Human Genetics
      Bonn, North Rhine-Westphalia, Germany
  • 2011
    • Sheffield Children's NHS Foundation Trust
      Sheffield, England, United Kingdom
    • Charité Universitätsmedizin Berlin
      • Department of Dermatology, Venerology and Allergology
      Berlin, Land Berlin, Germany
  • 1984–2011
    • The University of Sheffield
      • Department of Biomedical Science
      Sheffield, England, United Kingdom
  • 2008
    • National Skin Centre
      Tumasik, Singapore
  • 2006
    • Saint Vincent Hospital
      Worcester, Massachusetts, United States
  • 1991–2006
    • University of Bradford
      • Bradford School of Medical Sciences
      Bradford, ENG, United Kingdom
    • Unilever
      Londinium, England, United Kingdom