beta-endorphin and Vitiligo

Quality of life in patients with vitiligo is impaired. This study explored the immediate effect of 20 days of climatotherapy at the Dead Sea on quality of life, coping with the disease, general well-being and individual stress levels in a group of 71 patients with vitiligo and 42 matched controls. The long-term effect was assessed after 12 months in 33/71 patients and 12/42 controls. Study instruments were Dermatology Life Quality Index, Beck Depression Inventory and the Adjustment to Chronic Skin Disorders Questionnaire. Stress measurements were based on cortisol and β-endorphin concentrations in saliva samples. Quality of life was significantly improved at day 20 at the Dead Sea compared with day 1, and this was still significant after 12 months. Moreover, social anxiety/avoidance, anxious-depressive mood and helplessness as measured by the Adjustment to Chronic Skin Disorders Questionnaire were significantly reduced. There was no difference in levels of cortisol and β-endorphin between patients and controls, indicating that stress per se is not a significant contributor in vitiligo. In conclusion, therapy in patient groups offers an effective tool for long-lasting improvement in quality of life and patients' well-being.

Topics: Adaptation, Psychological; Adult; Antioxidants; Anxiety; beta-Endorphin; Catalase; Climatotherapy; Combined Modality Therapy; Depression; Female; Humans; Hydrocortisone; Male; Middle Aged; Psychotherapy, Group; Quality of Life; Saliva; Stress, Psychological; Surveys and Questionnaires; Time Factors; Vitiligo

The human skin holds the capacity for autocrine processing of the proopiomelanocortin (POMC)-derived peptides. Recent data demonstrated the presence and functionality of ACTH, alpha- and beta-melanocyte-stimulating hormone (MSH), and beta-endorphin in the regulation of skin pigmentation, and a role has been put forward for alpha-MSH as an effective antioxidant. In patients with vitiligo, decreased epidermal POMC processing and low alpha-MSH levels were documented previously. These patients accumulate hydrogen peroxide (H2O2) in the 10(-3) M range in their epidermis. Therefore, we examined the involvement of H2O2 on POMC-derived peptides as possible targets for oxidation by this reactive oxygen species. To address this, we employed immunofluorescence labelling, dot blot analysis, Fourier transform Raman spectroscopy, functionality studies, and computer simulation of the peptide structures. We demonstrate H2O2-mediated oxidation of epidermal ACTH, alpha-MSH, and beta-endorphin in vitiligo owing to oxidation of methionine residues in the sequences of these peptides. Moreover, we show that oxidized beta-endorphin loses its function in the promotion of pigmentation in melanocytes. These changes are reversible upon the reduction of H2O2 levels by a pseudocatalase PC-KUS. Moreover, oxidation of alpha-MSH can be prevented by the formation of a 1:1 complex with the abundant cofactor (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin. Thus, using vitiligo, we demonstrate that H2O2 can affect pigmentation via epidermal POMC peptide redox homeostasis.

Topics: Adrenocorticotropic Hormone; alpha-MSH; beta-Endorphin; Biopterins; Catalase; Cells, Cultured; Computer Simulation; Epidermis; Fourier Analysis; Humans; Hydrogen Peroxide; Melanins; Models, Biological; Oxidation-Reduction; Oxidative Stress; Peptide Fragments; Pro-Opiomelanocortin; Skin Pigmentation; Spectrum Analysis, Raman; Vitiligo

In order to study the possible role of beta-endorphin in the pathogenesis of vitiligo, the authors measured the levels of beta-endorphin in the plasma from 40 patients and the tissue fluids of skin lesions and uninvolved skin from 33 patients with vitiligo, using a 125I RIA kit. The results showed that the levels of plasma beta-endorphin in the patients with vitiligo of all of the generalized, focal and segmental types and in either progressive and stable stages were significantly higher then the normal controls. The levels of beta-endorphin in the tissue fluids from skin lesions were significantly higher than those from uninvolved skin in both the local type and segmental type. In the generalized type, the levels of beta-endorphin were obviously increased in both the tissue fluids from skin lesions and those from uninvolved skin. It seems that beta-endorphin plays a role in the pathogenesis of vitiligo.

Topics: beta-Endorphin; Humans; Skin; Vitiligo

The immune system is important in the pathogenesis of vitiligo, and emotional stress has precipitated vitiligo in some patients. Opioid peptides, beta-endorphin, met-enkephalin, and alpha-melanocyte-stimulating hormone (MSH) act as immunomodulators, and their secretion increases during periods of stress.. To see whether these three neuropeptides might be related to vitiligo itself or to some alterations of the immune system in patients with vitiligo, we compared circadian variations in their plasma concentrations and natural killer cell activity of peripheral blood lymphocytes in 14 patients with vitiligo with those of 12 healthy subjects.. Plasma concentrations of neurohormones were evaluated by radioimmunoassay (immunoradiometric assay for beta-endorphin). Natural killer cell activity (NKCA) was assayed against K562 cells by 51Cr release technique. Data were compared by the Student t test and analyzed by cosinor analysis.. The NKCA in vitiligo patients was higher than in controls but had similar circadian rhythm. alpha-MSH had no circadian rhythm in controls or in patients; plasma alpha-MSH levels were the same. Daily met-enkephalin and beta-endorphin oscillations in patients were no longer circadian. beta-Endorphin plasma levels in stable vitiligo were higher than in controls. There were no differences between patients with active vitiligo and normal subjects. Met-enkephalin plasma levels were generally higher in vitiligo patients, especially in the one with active vitiligo, than in controls.. In vitiligo there are aberrations in neuropeptide, beta-endorphin, and met-enkephalin secretion. The plasma met-enkephalin level is positively correlated with the aggressiveness of the disease.

Topics: Adult; alpha-MSH; beta-Endorphin; Chronic Disease; Circadian Rhythm; Cytotoxicity Tests, Immunologic; Enkephalin, Methionine; Female; Humans; Killer Cells, Natural; Male; Middle Aged; Radioimmunoassay; Regression Analysis; Vitiligo