Effect of melatonin on oxidative stress markers in patients with alopecia areata

multifocal disorder of hair , nonscarring , Alopecia areata is an autoimmune which occur on any hair bearing site , characterized by circular bald areas growth of the Recent study reported a potential . The exact cause of alopecia areata is unknown . body . in pathogenesis of alopecia areata ) OFR ( oxygen free radicals role of study was designed to evaluate the antioxidant effect of melatonin This clinical two This study revealed that . in patients with alopecia areata ) mg every other day ٣ ( month treatment with melatonin antioxidant led to a decrease in the basal level of malondialdehyde (MDA) an index of lipid peroxidation, an increase in basal glutathione (GSH) content a major endogenous antioxidant in both plasma and erythrocytes and an increase in plasma total antioxidant status( TAS ) . The most important point is the clinical significance of antioxidants in improving the hair growth response of patients with alopecia areata. This may be due to direct and/or indirect effect of melatonin on immune system. The direct effect may be through its immunoenhancing / immunostimulatory properties of melatonin.The indirect effect is the scavenging activity of this antioxidant, which in turn decrease damaging effect of oxygen free radicals (OFR) and utilization of GSH in neutralizing phagocytesinduced free radicals. So replenishment of GSH within natural killer (immune) cells strengthens the immune system and increases the rate of hair growth.


Introduction
lopecia areata is a nonscarring hair-loss condition that often has a patchy distribution and can be quite unpredictable (١-٣) .Alopecia areata is believed to be an autoimmune disease (٤- ٦) involving T lymphocytic infiltration around the hair follicle (٧,٨) .Therapeutic options depend on several factors, including amount of hair-bearing skin involved and the age of the patient (٩)  Intralesional steroids have been a mainstay of treatment.Topical steroids, anthralin, and minoxidil are additional therapeutic modalities that have been used with mixed success over the last several years (١,٢)  ) ١٣ ( makes them more responsive the key targets for melatonin is the thymus as a central organ of the .immune system Therefore, an oxidative stress may play an important role in hair loss in patients with alopecia areata, this clinical study was aimed at evaluating the antioxidant effect of melatonin and the degree of its effects on the levels of oxidative stress markers in patients with alopecia areata.months.C-Samples: heparinized venous blood samples were collected from alopecic patients as well as from controls using plastic disposable syringes.Fresh blood samples were used for MDA and GSH measurements in plasma and RBCs .Measurement of plasma and erythrocytes MDA based on the reaction of thiobarbituric acid (TBA) forming TBA-MDA adduct, was carried out using the modified method of Stocks and Dormandy (١٦) as described by Gilbert et al (١٧) .The results were expressed as OD /ml and OD/ g Hb respectively .Measurement of plasma and erythrocytes GSH content was determined to the method of Godin et al. (١٨) .Amounts of GSH were expressed as OD/ml and OD/g Hb respectively.Plasma samples were frozen up to ١٤ days for total antioxidant status measurement (TAS) using commercial assay kit obtained from Randox(١٩).Data were analyzed using t-test.

Results
The baseline mean of plasma and erythrocytes MDA concentrations in patients with alopecia areata was significantly higher than those of controls.
Treatment with the antioxidant melatonin normalized MDA levels in plasma and RBCs after ٢ months after treatment (Table ١).
Basal level of plasma GSH concentrations in patients with alopecia areata were significantly higher than those of controls .Treatment with melatonin did not normalize these levels, but rather had a significant effect in further increasing plasma GSH levels.
Furthermore, the basal mean RBCs GSH and plasma TAS levels were significantly lower in patients with alopecia areata than those of controls.Treatment with melatonin did significantly elevate GSH content and TAS levels to normal level in patients with alopecia areata after two months of treatment (Table ١).Clinically, there was an obvious improvement in rate of hair growth after ١ and ٢ months of treatment with the combination of the melatonin and traditional treatment as shown in the following pictures .

Table(١):
Markers of oxidative stress in patients with alopecia areata with their aged matched controls before and after two months treatment with a ٣ mg melatonin each other day.

Discussion
Various studies in humans and animals have shown that melatonin has a especially , immune effect -powerful pro aging or diseased , in stressed noted that chronic They .The present study demonstrated, for the first time, the presence of [alterations in TAS].no comparable study is available in the literature in this regard and further studies are needed to investigate the mechanism (s) responsible for this finding.It seems alterations in oxygen free radical scavenging processes in erythrocytes and plasma of patients with alopecia areata manifested by a decrease in plasma antioxidant status (TAS) .It seems that antioxidant defenses remain high in normal individual, keeping lipid peroxidation under control.However, in alopecic patients antioxidant defenses are significantly lowered, thus exposing erythrocytes to the damaging effects of lipid peroxides.This may be due to a direct and/or indirect effect of alopecia, per se , where the already formed immune complex resulted in the production of phagocytes-derived free radicals, which will lead to the initiation of lipid peroxidation as manfisted by the significant increase in total endogenous basal MDA levels.GSH, a major scavenger of oxygen reactive intermediates, protect cells against the effect of free radical and of related intermediates (e.g.peroxides) that are formed endogenously (٢١) .Therefore, a reduction in cellular GSH may be associated with an increased susceptibility to oxidant stress or reflect a response to it (٢٢) .A considerable decrease in the red cell GSH has already been reported in patients with alopecia (٢٣) .In the present study, the decreased total GSH content in red cells may be due to the increased GSH utilization in neutralizing oxygen free radical produced by phagocytes.These changes in GSH level may increase the susceptibility of erythrocytes and plasma to endogenous oxidative stress.The fact that plasma GSH level of alopecic patients were higher than their controls may be a compensatory increase due to the release of oxidized GSH from tissues and pooled in plasma.The treatment with melatonin antioxidant led to decrease the basal level of MDA increase GSH in both plasma and erythrocytes, and increase plasma TAS.Furthermore,the most important clinical effect of melatonin combined with traditional treatment , in improving the hair growth responce of alopecic patients, has not been previously reported in the available litrature.This interesting and noval finding may be due to direct and/or indirect effects of melatonin.The direct effect include its immunostimulatory and immunoenhancing effects (٢٤,٢٥) which is particularly apparent in immunodepressive state.The immunoenhancing action of melatonin seems to be mediated by T-helper cellderived opioid peptides as well as by lymphokines and perhaps by pituitary hormones.
Melatonin-inducedimmuno-opioids and lymphokines imply the presence of specific binding sites or melatonin receptors on cells on immune system.On the other hand, lymphokines such as gamma-interferon and interleukin-٢ as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland (٢٦) .The indirect effect of melatonin include its scavenging activity, which in turn decrease both oxidative damage and utilization of GSH in neutralizing phagocytes induced free radicals.So replenishment of GSH within natural killer (immune) cells strengthens the immune system and increases the rate of hair growth.In conclusion, the present study further supports the role of oxidative stress in the pathogenesis of alopecia areata, and presents a novel evidence for the preferential effect of the powerful antioxidant and immunostimulating hormone, mela-tonin when combined with traditional treatment in correcting anti-oxidant status as well as improving the rate of hair growth in alopecia areata patients in comparison with the effects obtained from the use of traditional trea-tment alone.Further studies are required to invistigate the exact mechanism responsible for this novel effect of melatonin.