Vitamin D receptor gene polymorphisms are not associated with alopecia areata

BACKGROUND

It has been demonstrated that the vitamin D receptor (VDR) is strongly expressed in key structures of hair follicles, and a lack of VDR leads to alopecia. We investigated whether there was any association between VDR gene polymorphisms (BsmI, ApaI, and TaqI) and alopecia areata (AA).

METHODS

Thirty-two patients with AA and 27 healthy control subjects were genotyped using polymerase chain reaction and restriction fragment length polymorphism analysis.

RESULTS

In the patient group, the B and b allele frequencies were 53.1% and 46.9%, A and a allele frequencies were 70.3% and 29.7%, and T and t allele frequencies were 62.5% and 37.5%, respectively. In the control group, the corresponding values were 51.9% and 48.1%, 63.0% and 37.0%, and 77.8% and 22.2%, respectively. In the patient group, the BB, Bb, and bb genotype frequencies were 25.0%, 56.2%, and 18.8%, AA, Aa, and aa genotype frequencies were 43.8%, 53.1%, and 3.1%, and TT, Tt, and tt genotype frequencies were 37.5%, 50.0%, and 12.5%, respectively. In the control group, the corresponding values were 11.1%, 81.5%, and 7.4%, 29.6%, 66.7%, and 3.7%, and 63.0%, 29.6%, and 7.4%, respectively. None of the allele or genotype frequencies showed statistically significant differences between the patient and control groups.

CONCLUSION

These findings suggest that there is no relationship between VDR gene polymorphisms and AA.

Etanercept does not effectively treat moderate to severe alopecia areata: an open-label study

In this prospective, open-label pilot study, we evaluated the safety and efficacy of etanercept, a TNF-alpha inhibitor, in the treatment of moderate to severe alopecia areata, alopecia totalis, or alopecia universalis. Seventeen otherwise healthy adults with moderate to severe alopecia areata were enrolled. The primary outcome measure was the extent of hair regrowth during and after the end of treatment as evaluated by the Severity of Alopecia Tool (the SALT score). After between 8 and 24 weeks of continuous treatment with etanercept 50 mg given subcutaneously twice weekly, significant regrowth of hair was not shown in any of the subjects treated. Based on these results, etanercept appears to be ineffective in treating subjects with treatment-refractory, moderate to severe alopecia areata, alopecia totalis, or alopecia universalis.

Expression of vascular endothelial growth factor, apoptosis inhibitors (survivin and p16) and CCL27 in alopecia areata before and after diphencyprone treatment: an immunohistochemical study

BACKGROUND

Alopecia areata (AA) is a relatively common inflammatory form of nonscarring hair loss of unknown pathogenesis, but possibly of autoimmune origin. Topical immunotherapy, using a potent contact allergen such as diphencyprone (DPC), is currently considered the most effective mode of treatment. However, the way in which DPC operates on hair follicles in AA still remains to be elucidated. Vascular endothelial growth factor (VEGF), essential for angiogenesis and vascular permeability, may be responsible for maintaining proper vasculature around hair follicles, and several studies provide evidence that apoptosis is a central element in the regulation of hair follicle and vascular regression. The cutaneous lymphocyte-associated antigen (CLA) and the skin-associated chemokine CCL27 highlight an important role for epithelial cells in controlling homeostatic lymphocyte trafficking.

OBJECTIVES

To determine the expression pattern of VEGF, factor (F)VIII, survivin, p16, CD4, CD8, CLA and CCL27 in alopecic skin before and after treatment with DPC. Methods Immunohistochemical staining methods were applied to skin biopsy specimens obtained from alopecic areas of 14 patients before and after DPC treatment and from five healthy subjects. Sections were incubated with monoclonal antibodies against VEGF, FVIII, survivin, p16, CCL27, CLA, CD4 and CD8, and their immunohistochemical expression was evaluated by light microscopy.

RESULTS

The intensity of VEGF staining in alopecic human hair follicles was significantly lower than in healthy scalp tissue. FVIII immunostaining showed a significantly reduced development of the microvasculature in AA in comparison with healthy scalp tissue. After DPC therapy, cells of alopecic hair follicles showed a significant increase of VEGF immunopositivity, and the number of capillary vessels expressing FVIII was markedly increased in comparison with untreated scalp tissue. The increase in microvessels was associated with strong survivin expression in endothelial cells after treatment. All alopecic specimens showed expression of p16 in the hair follicle outer root sheath (ORS), with a significant increase after therapy. After treatment we observed a significantly decreased number of CD4+ cells and an increase of CD8+ cells (CD4/CD8 ratio 0.85) in alopecic skin compared with untreated scalp tissue (CD4/CD8 ratio 3.45). Most of the T lymphocytes found in inflammatory skin lesions expressed CLA antigen and after therapy we observed a significantly higher CLA positivity in hair follicles (50% or more) in comparison with untreated alopecic scalp tissue. Alopecic patients showed a CCL27 immunopositivity significantly lower than in normal scalp tissue. After DPC therapy the labelling intensity for CCL27 showed a significant increase both in the ORS and in the inner root sheath; similarly, in the basal interfollicular keratinocytes we observed a moderate increase in CCL27 expression.

CONCLUSIONS

Topical immunotherapy exerts an important role in angiogenesis, upregulating VEGF in human hair follicle keratinocytes and upregulating survivin to preserve endothelial cell viability. Moreover, it considerably alters the peribulbar CD4/CD8 ratio, restoring a condition close to normal scalp skin. Our study could contribute to explaining some aspects of AA pathogenesis that are still unknown and aid understanding of how DPC could act in this complex disease.

Autoimmunity: Alopecia Areata

Strong direct and indirect evidence supports an autoimmune etiology for alopecia areata. T lymphocytes that have been shown to be oligoclonal and autoreactive are predominantly present in the peribulbar inflammatory infiltrate. Alopecia areata frequently occurs in association with other autoimmune diseases, such as thyroiditis and vitiligo, and autoantibodies to follicular components have been detected. Finally, the use of immune modulating drugs, including corticosteroids and contact sensitizers such as dyphencyprone, can be beneficial in the management of this disease. Recent studies have demonstrated that alopecia areata scalp skin grafted onto nude mice with severe combined immunodeficiency grow hair and that infiltrating lymphocytes in the graft are lost. It is now also possible to induce alopecia areata in human scalp explants on these mice by injecting T lymphocytes with scalp homogenate. Neuropeptides produced by cutaneous nerves are known to modify immune reactivity and, in all likelihood, affect the alopecia areata process. Future studies may show that modulation of neuropeptide expression is associated with hair regrowth. Likewise, testing the efficacy of the newly developed immunomodulatory agents in patients with alopecia areata may lead to the introduction of novel therapies for this immune-mediated disease of the hair follicle.

Antioxidant enzymes and lipid peroxidation in the scalp of patients with alopecia areata

Alopecia areata (AA) is an autoimmune inflammatory disease. However, little is known about the alterations in lipid peroxidation and antioxidant enzymes in the scalp of patients with AA. Therefore, the aim of this study was to investigate the status of oxidative stress in the scalp of patients with AA. We measured the levels of thiobarbituric acid reactive substances (TBARS) as lipid peroxidation status, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) as antioxidant enzymes in the scalp of ten patients with AA and ten control subjects. The levels of TBARS in scalp of patients with AA (3654.1+/-621.2 nmol/g tissue) were significantly higher than those of controls (1210.2+/-188.8 nmol/g tissue) (P=0.002). The levels of SOD (134.8+/-23.8 U/g tissue) and GSH-Px (332.7+/-66.2 U/g tissue) in scalp of patients with AA were also significantly higher than those of controls (63.2+/-8.8 U/g tissue, 112.0+/-18.4 U/g tissue, respectively) (P=0.019, P=0.002, respectively). The mean levels of TBARS, SOD and GSH-Px in early phase of disease were increased 2-fold as compared with late phase of the disease. These results indicate that oxidative status is affected in AA. Lipid peroxidation and antioxidant enzymes may be involved in the pathogenesis of AA. Furthermore, we found high SOD and GSH-Px activities in the scalp of patient with AA. These high levels could not protect the patients against the reactive oxygen species, because lipid peroxidation could not be lowered in AA patients.