Krox20 expression in abnormal scars: An immunohistochemical study.

BACKGROUND: Scars are the end outcome of healing. They are grouped into several types, the common of which are keloids, hypertrophic, and atrophic scars. The role of Krox20 in skin and hair physiology and pathology had emerged. Overexpression of Krox20 was sufficient to stimulate collagen gene expression and myofibroblast differentiation and is necessary for transforming growth factor-ß (TGF-ß) induced profibrotic responses. OBJECTIVE: To investigate the role of Krox20 in abnormal scar pathogenesis. Hopefully, this insight can set the route for newer therapeutic approaches. MATERIALS AND METHOD: This study was carried out on 30 cases (10 cases of keloids, 10 cases of atrophic scars, and 10 cases with hypertrophic scars [HTS]) and 10 age and gender-matched apparently healthy subjects as a control group. Thirty biopsies were taken from perilesional areas. Evaluation of Krox20 expression was done using standard immunohistochemical technique. RESULTS: Krox20 was downregulated in epidermis of scar biopsies compared with perilesional and normal skin (p = 0.02) while it was overexpressed in fibroblasts in lesional scar biopsies compared with perilesional and normal skin (p < 0.001). Keloid cases have significantly higher Krox20 expression in fibroblasts compared with HTS cases (p < 0.001). Krox20 had significantly nucleocytoplasmic pattern of staining in scar cases compared with normal skin (p < 0.001). CONCLUSION: Krox20 overexpression may have a role in scar pathogenesis through upregulation of multiple genes associated with tissue remodeling and wound healing. This may open an avenue for research for new therapies based on Krox20 inhibition.

Serum nuclear factor E-2-related factor 2 in female pattern hair loss.

BACKGROUND: Female pattern hair loss (FPHL) is a common dermatological complaint with multifactorial etiology. Nuclear factor erythroid-2-related factor 2 (NRF2) is a transcription factor that has a major role in protection from ROS-induced apoptosis. AIM: To investigate the relationship between Nrf2 and systemic oxidative stress in FPHL patients. PATIENTS AND METHODS: This case-control study included 30 patients with FPHL and 30 age- and sex-matched healthy volunteers as a control group. Serum NRF2, total antioxidant capacity (TAC), and total oxidant capacity (TOC) were measured by ELISA, and oxidative stress index (OSI) was calculated. RESULTS: The serum level of TOC and OSI was found to be significantly higher (p ≤ 0.001 for both) while serum level of NRF2 and TAC was found to be significantly lower in cases than controls (p < 0.001 for both). There were a significant negative correlation between TAC and BMI (p = 0.03, r = -0.391) and a significant positive correlation between OSI and BMI (p = 0.04, r = 0.365). There were a significant positive correlation between serum level of NRF2 and TAC (p = 0.003, r = 0.532) and a significant negative correlation between serum the level of NRF2 and TOC (p = 0.02, r = -0.418) and OSI (p = 0.003, r = -0.395). CONCLUSION: Systemic oxidative stress in FPHL may be, at least in part, due to NRF2 deficiency. NRF2 activators may help in treatment of this disease. NRF2 deficiency has no role in disease severity. Healthy diet and body weight reduction may help in improving oxidative stress and subsequently improving FPHL.

Neutrophil Cytosolic Factor-1 Genotyping in Acne Vulgaris.

Acne vulgaris (AV) is a very common inflammatory dermatosis. It has a complex pathogenesis in which oxidative stress plays an important role. Neutrophil cytosolic factor (NCF)-1 gene encodes for NCF1 protein which shares in reactive oxygen species (ROS) production. Copy number variation (CNV) is a type of genetic variance in which gene copies are duplicated or deleted. The current work aimed to detect the association between NCF1 CNV and NCF-1 genotypes and AV to explore their possible role in increased disease risk or influencing its clinical presentation. Twenty-five cases with AV and 25 age- and gender-matched healthy volunteers were selected. NCF1 CNV and genotypes were determined using quantitative real-time polymerase chain reaction. NCF1 copy number was significantly increased in patients compared to the control group (p = 0.02). Higher copy number increased the risk of occurrence of AV by about 4-fold. The NCF1 genotype was more prevalent in patients (72%) compared to NCF1B (24%) and NCF1C (4%) variants, while NCF1B and NCF1C variants (68%) were more prevalent in the control group. The NCF1B genotype decreased the risk of occurrence of AV by 0.2-fold. NCF1 was significantly associated with cases more than controls (p = 0.005). It increased the risk of occurrence of acne by 5.4-fold. There was significant association between NCF1 copy number and disease duration where higher number was associated with long disease duration (p = 0.03). Higher copy number was also associated with the NCF1 genotype (p = 0.01). This study suggests that increased copy number of NCF1 gene may be a predisposing factor for AV development. However, the presence of NCF1B and NCF1C variants lowers ROS production and subsequently decreases the risk of development of AV.

Vitamin D Receptor Gene Polymorphisms Taq-1 and Cdx-1 in Female Pattern Hair Loss.

BACKGROUND: Female pattern hair loss (FPHL) is an important cause of hair loss in adult women and has a major impact on patient's quality of life. It evolves from the progressive miniaturization of follicles that leads to a subsequent decrease of hair density, leading to non-scarring diffuse alopecia, with characteristic clinical, dermoscopic, and histological patterns. Vitamin D receptor (VDR) is expressed in follicular keratinocytes and dermal papilla cells and is shown to have important role in hair growth and regulation of hair cycle. VDR polymorphism was not extensively investigated in hair disorders including FPHL. AIM: To investigate the association between VDR gene polymorphism (Cdx-1 and Taq-1) and FPHL to explore if these polymorphisms affect the disease occurrence or influence its clinical presentation. METHODS: A case-control study was conducted on 30 female patients with FPHL and 30 age-matched female healthy subjects, as a control group. Degree of hair loss was assessed by Ludwig grading. VDR gene polymorphisms, Taq-1 and Cdx-1 were investigated by real time polymerase chain reaction. RESULTS: CC genotype, TC genotype, and T allele of Taq-1 were more prevalent in FPHL patients than in control group. They increased disease risk by 12.6, 2.1, and 2.9 folds, respectively. AA genotype, GA genotype, and G allele of Cdx-1 were significantly more prevalent among FPHL patients than in control group. They increased disease risk by 7.5, 5.2, and 5.5 folds, respectively. CONCLUSION: Taq-1 and Cdx-1 can be considered as risk factors for FPHL. They may play role in disease persistence rather than disease initiation. This association may be explained by failure of new anagen growth and decreased proliferation of hair follicle stem cells. Further studies are recommended to confirm current findings.

Vitamin D Receptor Gene Polymorphism In Chronic Telogen Effluvium; A Case-Control Study.

BACKGROUND: Telogen effluvium (TE) is a form of alopecia characterized by diffuse hair shedding. Vitamin D receptor (VDR) plays a role in hair cycle regulation as it is expressed in follicular keratinocytes and dermal papilla cells. PURPOSE: To investigate the association between Cdx1 and Taq1 VDR gene polymorphisms and chronic TE. METHODS: Thirty female patients with chronic TE were selected and 30 healthy, age- and sex-matched volunteers were included as a control group. Detection of VDR gene polymorphisms Taq1 and Cdx1 was done by real-time polymerase chain reaction. RESULTS: Regarding Taq 1, CC genotype was present in 30% of cases versus 3.3% of controls. TC genotype was present in 33.3% of cases and 36.7% of controls. CC genotype was significantly associated with cases (P=0.01). It increases the risk of chronic TE by 14.7 folds. C allele was significantly associated with patient group (P=0.004). It increases the risk of disease occurrence by 3.1 folds. Regarding Cdx1, AA genotype was present in 6.7% of cases versus 3.3% of controls. GA genotype was present in approximately 30% of cases and 6.7% of controls. GA genotype was significantly associated with cases (P=0.03). It increases the risk of chronic TE by 6.3 folds. A allele was significantly associated with patient group (P=0.007). It increases the risk of disease occurrence by 3.8 folds. LIMITATIONS: The main limitation is the small number of cases due to the time and financial constraints. Only chronic TE was analyzed, therefore, other types should be investigated in the following studies. CONCLUSION: After exposure to primary physical or mental stressor, hair follicles are stimulated to enter prematurely into telogen and shed out. In individuals with Taq1 and Cdx1 polymorphisms, the disease persists as a result of prevention of new anagen growth and inhibition of hair follicle stem cell proliferation.

Peroxisome Proliferator-Activated Receptor-γ Gene Polymorphism in Psoriasis and Its Relation to Obesity, Metabolic Syndrome, and Narrowband Ultraviolet B Response: A Case-Control Study in Egyptian Patients.

BACKGROUND: Psoriasis is a common dermatologic disease with multifactorial etiology in which genetic factors play a major role. Peroxisome proliferator-activated receptor (PPAR)-γ is expressed in keratinocytes and is known to affect cell maturation and differentiation in addition to its role in inflammation. AIM: To study the association between PPAR-γ gene polymorphism and psoriasis vulgaris in Egyptian patients to explore if this polymorphism influenced disease risk or clinical presentation. METHODS: Forty-five patients with psoriasis vulgaris and 45 age, sex and body mass index matched healthy volunteers who have no present, past or family history of psoriasis as a control group were enrolled. Selected cases included obese and nonobese participants. Detection of PPAR-γ gene polymorphism was done with restriction fragment length polymorphism polymerase chain reaction. Narrow-band ultraviolet B (NBUVB) was given for every case three times/week for 12 weeks. RESULTS: Homopolymorphism, heteropolymorphism, and Ala allele were significantly associated with cases (P = 0.01, P = 0.01, and P = 0.004, respectively) and increased risk of occurrence of psoriasis by 5.25, 3.65, and 3.37 folds, respectively. Heteropolymorphism was significantly associated with nonobese cases compared to obese ones (P = 0.01). Ala allele was significantly associated with obese cases (P = 0.001) and increased risk of occurrence of psoriasis in obese participants by 1.14 folds. Homopolymorphism, heteropolymorphism, and Ala allele were more prevalent among obese cases without metabolic syndrome (MS) than obese cases with MS but without statistical significance. Percentage of decrease of mean Psoriasis Area and Severity Index score before and after 3 months of treatment with NBUVB was higher in cases with heteropolymorphism with no significant difference between homo- and heteropolymorphism. CONCLUSION: PPAR-γ gene polymorphism is associated with and increased the risk of psoriasis and its associated obesity in Egyptian patients. It has no role in NBUVB response in those patients. Future large-scale studies on different populations are recommended.

Polymorphism of FAS and FAS Ligand Genes in Alopecia Areata: A Case-control Study in Egyptian Population.

BACKGROUND: Alopecia areata (AA) is a common dermatologic disease with suspected autoimmune etiology. Tumor necrosis factor superfamily member 6 or CD95 (FAS) and FAS ligand (FASL) are proapoptotic proteins. The relationship between apoptosis and autoimmunity is well recognized. Inflammatory T cells in AA are cytotoxic and possess FAS/FASL antigens. AIM: This study aims to investigate the association between FAS-670 A/G and FASL-124 A/G gene polymorphisms and AA to clarify if these polymorphisms influence disease occurrence or increase disease risk. MATERIALS AND METHODS: A case-control study was conducted on sixty patients with AA, and 40 age- and sex-matched healthy subjects, as a control group. Disease severity was assessed by severity of alopecia tool (SALT) Score. FAS 670A/G and FASL 124A/G gene polymorphisms were investigated by the restriction fragment length polymorphism polymerase chain reaction. RESULTS: For FAS gene, G/G genotype was significantly higher in cases than in control group with odds ratio 5.1. G allele was more prevalent among patient group with odds ratio 1.75. For FASL gene, A/G genotype was significantly higher in cases than in control group with odds ratio 4.53. G allele was more prevalent among patient group with odds ratio 1.88. GG genotype of FAS was significantly associated with longer disease duration (P =0.001), recurrent attacks (P =0.01), higher SALT score (P =0.009), alopecia universalis (P =0.002), and severe disease (P =0.006). CONCLUSION: FAS and FASL gene polymorphisms are associated with AA. Further large-scale studies on different ethnicities are required for more clarification of their role in disease development. Therapeutic modalities based on their inhibition could be promising in the treatment of a common disease like AA.

Re-appraisal of Keratinocytes' Role in Vitiligo Pathogenesis.

BACKGROUND: Vitiligo is a common pigmentary disorder. Studies on its pathogenesis extensively investigated melanocytes' abnormalities and few studies searched for keratinocytes' role in disease development. Liver X receptor-α (LXR-α) is a member of nuclear hormone receptors that acts as a transcription factor. Its target genes are the main regulators of melanocyte functions. AIM: The aim of this study is to investigate keratinocytes' role in vitiligo pathogenesis through immunohistochemical expression of LXR-α in lesional, perilesional, and distant nonlesional vitiligo skin. MATERIALS AND METHODS: This case-control study was carried out on 44 participants. These included 24 patients with vitiligo and 20 age- and sex-matched normal individuals as a control group. Biopsies, from cases, were taken from lesional, perilesional, and distant nonlesional areas. Evaluation was done using immunohistochemical technique. RESULTS: Keratinocyte LXR-α expression was upregulated in the lesional and perilesional skin (follicular and interfollicular epidermis) compared with control skin (P <0.001 for all). There was significant association between higher histoscore (H-score) in lesional epidermis (P <0.001) and in hair follicle (P =0.001) and the presence of angiogenesis. There was significant association between higher H-score in lesional epidermis and suprabasal vacuolization (P =0.02). No significant association was found between H-score or expression percentage and clinical data of selected cases. CONCLUSION: LXR-α upregulation is associated with keratinocyte damage in vitiligo lesional skin that leads to decreased keratinocyte-derived mediators and growth factors supporting the growth and/or melanization of surrounding melanocytes. Therefore, melanocyte function and survival are affected.

Morphometric and ultrastructural analysis of tramadol effects on epididymis: an experimental study.

The effect of tramadol addiction on epididymal structure was not investigated before. Therefore, this experimental study was carried out to investigate the effect of chronic tramadol use on the epididymal structure using light and electron microscopies. Thirty adult Wister Albino male rats were divided into two groups: control group (five rats) and tramadol-treated group (25 rats), which was further subdivided into five subgroups that received tramadol orally at 4.5, 9, 45, 90, and 135 mg/kg/day, respectively, for 18 weeks. Epididymal tissues were dissected and processed for histopathological examination. Morphometric analysis showed significantly reduced mean values of epididymal ducts' diameters and epithelial height in the tramadol-treated group compared with the control group. Light microscopic examination revealed degeneration and necrosis of epididymal cells in the tramadol-treated group. Electron microscopic (EM) examination showed ultrastructure alterations in a dose-dependent manner. In conclusion, tramadol can adversely affect all epididymal cells, which subsequently deteriorate epididymal function and may affect sperm maturation, leading to subfertility.

Identification of Genotypes and Allelic Frequencies of Vitamin D Receptor Gene Polymorphism (TaqI) in Egyptian Melasma Patients.

BACKGROUND: Melasma is a characteristic pattern of facial hyperpigmentation, occurring primarily on the forehead, cheeks, and chin, in a mask-like distribution. The pathogenesis of melasma is not fully understood. Vitamin D plays a role in skin pigmentation. It exerts its effect through vitamin D receptor (VDR), which is expressed in variable cells including normal melanocytes. AIM AND OBJECTIVE: The aim of the current work was to investigate if VDR gene polymorphism (TaqI) confers susceptibility to melasma in Egyptian patients. MATERIALS AND METHODS: A total of 45 female patients with melasma were recruited and 50 healthy subjects that were matched on age, sex, body mass index, and skin phototype, were included as a control group. TaqI polymorphism was investigated using restriction fragment length polymorphism polymerase chain reaction (RFLP PCR). RESULTS: Presence of (t) allele and (tt) genotype was significantly associated with melasma cases compared with control group (P < 0.001 for both). No significant association was found between (tt) genotype or (t) allele and clinical data of the studied cases. CONCLUSION: TaqI polymorphism is associated with melasma. Further, large-scale studies are recommended to underscore and validate the current findings. It is also necessary for future studies to extend the research to other populations and ethnicities. Investigating other VDR gene polymorphisms in melasma is also warranted. Since melasma is a multifactorial disease, gene-gene and gene-environment interactions should be considered in future genetic-epidemiologic researches to apply more comprehensive insight into the role of VDR gene in its pathogenesis.

Immunohistochemical Expression of Cyclo-oxygenase 2 and Liver X Receptor-α in Acne Vulgaris.

INTRODUCTION: Acne Vulgaris (AV) is a common inflammatory disease of pilosebaceous units. Liver X Receptor-α (LXR-α) is a ligand activated transcription factor. It controls transcription of genes involved in lipid and fatty acid synthesis. Cyclo-oxygenase 2 (COX2) is a rate limiting enzyme in prostaglandin synthesis. It plays important role in inflammation. AIM: To evaluate the immunohistochemical expression of LXR-α and COX2 in acne vulgaris skin biopsies to explore their possible pathogenic role in this disease. MATERIALS AND METHODS: Sixty five subjects were included (45 cases with AV and 20 age and gender-matched healthy controls). Skin biopsies were taken from lesional and perilesional skin of cases and from site-matched areas of control subjects. The evaluation of LXR-α and COX2 was done using immunohistochemical technique. Data were collected, tabulated and statistically analysed using a personal computer with "(SPSS) version 11" program. Chi-square test was used to study the association between qualitative variables. Mann-Whitney test was used for comparison between quantitative variables. Student's t-test was used for comparison between two groups having quantitative variables. Spearman's coefficient was used to study the correlation between two different variables. Differences were considered statistically significant with p<0.05. RESULTS: COX2 was upregulated in lesional skin compared with peilesional and control skin both in epidermis and pilosebaceous units (p<0.001 for all). Higher epidermal COX2% was significantly associated with papulopustular acne (p=0.009) and higher acne score (p=0.018). Higher pilosebaceous units COX2% was significantly associated with papulopustular acne (p=0.04). LXR-α was upregulated in lesional skin compared with peilesional and control skin both in epidermis and pilosebaceous units (p<0.001 for all). Higher LXR-α % in epidermis and pilosebaceous units was significantly associated with papulopustular acne (p=0.01 for both) and higher acne score (p=0.03 for both). Significant positive correlation was detected between COX2% and LXR-α % in epidermis (p=0.001, r=0.87) and pilosebaceous units (p=0.001, r=0.65). CONCLUSION: Both LXR-α and COX-2 play a role in the pathogenesis of acne vulgaris through their effects on cellular proliferation, inflammation and lipid synthesis. Research for new therapeutic modalities based on their inhibition is needed. More understanding of the interaction between LXR-α, COX2 and acne lesions may lead to effective interference, possibly directed toward specific cell types or steps within inflammatory pathways.

Evaluation of Hypoxia Inducible Factor-1α and Glucose Transporter-1 Expression in Non Melanoma Skin Cancer: An Immunohistochemical Study.

INTRODUCTION: Hypoxia Inducible Factor-1 (HIF-1) is a mediator enabling cell adaptation to hypoxia. It plays its role mainly through transcription of many target genes including Glucose Transporter-1 (GLUT-1) gene. AIM: The present work aimed at evaluating the pattern and distribution of HIF-1α and GLUT-1 in each case and control. MATERIALS AND METHODS: A case-control and retrospective study was conducted on archival blocks diagnosed from pathology department as, Basal Cell Carcinoma (BCC, 20 cases), cutaneous Squamous Cell Carcinoma (SCC, 20 cases) and 20 normal site-matched skin biopsies from age and gender-matched healthy subjects as a control. Evaluation of both HIF-1α and GLUT1 expression using standard immunohistochemical techniques was performed on cut sections from selected paraffin embedded blocks. RESULTS: HIF-1α was expressed in 90%, 35% and 100% of normal skin, BCC and SCC tumour islands respectively. It was up regulated in both BCC and SCC compared with normal skin (p= 0.001, p<0.001 respectively). GLUT-1 was expressed in 100%, 70% and 100% of normal skin, BCC and SCC tumour islands respectively. It was down regulated in Non Melanoma Skin Cancer (NMSC) cases compared with normal skin (p=0.004). HIF-1α and GLUT-1 localization in tumour nests was central, peripheral or central and peripheral. Both HIF-1α and GLUT-1 showed variable expression in stroma, adnexa and inflammatory cells. No significant correlation was found between Histo (H) score or expression percentage values of HIF-1α and those of GLUT-1 in tumour islands or in overlying epidermis either in BCC or SCC. CONCLUSION: HIF-1α may have a role in NMSC pathogenesis through adaptation to hypoxia which results from excessive proliferation. GLUT-1 down regulation in NMSC may be explained by its consumption by proliferating tumour cells. The expression of HIF-1α and GLUT-1 in normal epidermis, stromal and adnexal structures needs further research.

Is Aquaporin-3 a Determinant Factor of Intrinsic and Extrinsic Aging? An Immunohistochemical and Morphometric Study.

Aquaporin-3 (AQP3) is an aquaglyceroporin that plays a role in skin hydration, cell proliferation, and migration. The aim of this work was to investigate the expression of AQP3 in sun-exposed and sun-protected human skin from different age groups to understand the relationship between AQP3 and skin aging. Using standard immunohistochemical techniques, sun-exposed and sun-protected skin biopsies were taken from 60 normal individuals. AQP3 was expressed in the basal and the suprabasal layers, sparing the stratum corneum, in all specimens. Dermal expression was detected in fibroblasts, endothelial cells, and adnexa. Sun-protected skin showed a significantly higher epidermal H-score and percentage of expression (P=0.002 and <0.001, respectively) compared with sun-exposed skin. The AQP3 expression intensity showed a gradual decrease from the 20 to 35-year-old group to the 35 to 50-year-old group, with the least immunoreactivity in the above 50-year-old group. A significant difference was detected in the H-score in favor of the 20 to 35-year-old group in sun-exposed and sun-protected skin (P<0.001 for both). A significant negative correlation was noted between the AQP3 expression percentage and the age in sun-exposed (r=-0.64, P<0.001) and sun-protected skin (r=-0.53, P<0.001). In conclusion, the skin dryness observed in intrinsic and extrinsic aged skin may be explained, at least in part, by AQP3 downregulation. This may open new avenues sufficient to control skin texture and beauty. Its interaction in skin protein organization and gene polymorphism can also be tackled in future research. In addition, clinical trials using AQP3 topical applications should be carried out to evaluate its effectiveness in the reversal of age-related skin changes.

Immunohistochemical Evaluation of Role of Serotonin in Pathogenesis of Psoriasis.

INTRODUCTION: Psoriasis is a common skin disorder characterized by erythaematosquamous papules and plaques. It is known to be associated with stressful and depressive disorders. Serotonin is a neurotransmitter that plays a role in the pathogenesis of inflammatory skin disorders. AIM: To evaluate the role of serotonin in pathogenesis of psoriasis. MATERIALS AND METHODS: Using standard immunohistochemical techniques, 24 biopsies from patients with chronic plaque psoriasis were examined together with 12 biopsies from age and gender-matched healthy subjects as a control group. RESULTS: Both the percentage of positive cells (p=0.018) and H-score values (p=0.015) of serotonin expression were significantly higher in psoriasis compared to normal skin. H score of serotonin expression was significantly higher in cases with totally absent Granular Cell Layer (GCL) as opposed to those with thin/focally absent GCL (p=0.011), and in cases with moderate/strong epidermal inflammation compared to cases with mild inflammation (p=0.035). No significant correlation was detected between H score of cases and age, disease duration or Psoriasis Area and Severity Index (PASI) score. CONCLUSION: Serotonin might play a role in development of psoriasis through its role as a growth factor promoting keratinocyte proliferation, and as mediator of inflammation and stimulant of T cell activation. It recruits T cells to sites of cutaneous inflammation and potentiate macrophage accessory function for T cell activation. Its expression is not related to the disease severity. Future large-scaled research on population of different ethnicities including other disease variants is needed. The use of serotonin receptor antagonists and serotonin reuptake inhibitors may be evaluated on wide-based studies to put the current observation into action.

Serum Vitamin D in patients with alopecia areata.

BACKGROUND: Alopecia areata (AA) is a common, recurrent, autoimmune hair disorder. It has been found that vitamin D deficiency is associated with many autoimmune diseases. AIMS: The current study aimed to estimate serum levels of 25-hydroxy vitamin D in patients with AA. MATERIALS AND METHODS: This case-control study included 60 patients with AA and 60 age, gender, skin phototype, and body mass index-matched healthy subjects as a control group. Levels of serum 25-hydroxy vitamin D were estimated using ELISA technique. RESULTS: Serum 25-hydroxy vitamin D levels were significantly lower in AA cases when compared with healthy controls (P < 0.001). The least values were significantly associated with alopecia totalis/universalis compared with patchy AA (P < 0.001) and ophiasis (P = 0.04). Severe AA showed significantly the lowest vitamin D levels compared with cases with mild (P = 0.002) and moderate disease (P = 0.03). A significant inverse correlation was found between 25-hydroxy vitamin D levels and age of the patients (r = -0.38; P = 0.03). There was no significant association between serum 25-hydroxy vitamin D levels and gender, disease duration, disease recurrence, nail affection, duration of sun exposure/day, or positive family history of AA. CONCLUSION: AA patients have lower levels of 25-hydroxy vitamin D than healthy subjects. More studies are required to assess the value of vitamin D supplementation in the treatment of that disease.

Intrinsic versus Extrinsic Aging: A Histopathological, Morphometric and Immunohistochemical Study of Estrogen Receptor ß and Androgen Receptor.

Skin is a target organ of sex steroids which play important roles in skin health and disease. The aim of this study is to investigate the expression of estrogen receptor ß (ERß) and androgen receptor (AR) in human skin from different age groups for a better understanding of the hormonal regulation of skin aging. Using standard immunohistochemical techniques, biopsies of sun-unprotected and sun-protected skin were taken from 60 normal subjects. Sun-protected skin showed significantly higher immunoreactivity for ERß and AR compared to sun-unprotected skin of all age groups. Significantly higher ERß H score and percent of expression were associated with the 20-35 years age group compared to the groups that were 35-50 years and >50 years old (p < 0.02, p = 0.03, respectively) in sun-unprotected and sun-protected skin (p < 0.001, p = 0.01, respectively). AR H score showed a negative correlation with age (p = 0.04) with no significant difference in immunoreactivity in different age groups, either in sun-unprotected or sun-protected skin. There was also a significant correlation between ERß H score and epidermal thickness in sun-unprotected (p = 0.04) and sun-protected skin (p = 0.04) in studied subjects regardless of age. The same relationships did not reach significance with AR expression. However, a significant positive correlation was detected between H scores and percent of expression of ERß and AR in sun-unprotected (p = 0.01, p = 0.02, respectively) and sun-protected skin (p = 0.005, p = 0.02, respectively) regardless of age. In conclusion, both ERß and AR decline gradually with intrinsic and extrinsic aging. This decline is more obvious with extrinsic aging. Further large-scaled studies are recommended to expand, validate and translate current findings to clinically significant, diagnostic and therapeutic applications. Molecular studies to investigate the probable ligand-independent action of both receptors are warranted. In addition, their gene expression patterns and associated signaling and metabolic pathways can also be tackled to provide a basis for further interventions in pathological processes that involve their dysregulation.