Evaluation of free oxygen radical and antioxidant capacity in alopecia areata

Alopecia Areata: A Review of the Role of Oxidative Stress, Possible Biomarkers, and Potential Novel Therapeutic Approaches

Alopecia areata (AA) is a dermatological condition characterized by non-scarring hair loss. Exact etiopathogenesis of AA is still unknown although it is known that several factors contribute to the collapse of the hair-follicle (HF)-immune-privileged (IP) site. Oxidative stress (OS) plays an important role in skin diseases. The aim of this review was to clarify the role of OS in AA pathogenesis and diagnosis, and to discuss potential treatment options. Oxidative-stress markers are altered in serum and skin samples of patients with AA, confirming a general pro-oxidative status in patients with AA. OS induces MHC class I chain-related A (MICA) expression in HF keratinocytes that activates the receptor NKG2D, expressed in NK cells and CD8+ T cytotoxic cells leading to destabilization of the HF immune-privileged site through the production of IFN-γ that stimulates JAK1 and JAK2 pathways. OS also activates the KEAP1-NRF2 pathway, an antioxidant system that contributes to skin homeostasis. In addition, a decrease of ATG5 and LC3B in the hair matrix and an increase in p62 levels indicates a reduction of intrafollicular autophagy during the evolution of AA. Potential biomarkers of OS in AA could be: malondialdehyde (MDA), advanced glycation end-products (AGEs), and ischemic-modified albumin (IMA). JAK inhibitors are the new frontier in treatment of AA and the use of nutraceuticals that modulate the OS balance, in combination with standard treatments, represent promising therapeutic tools.

Does oxidative stress correlate with disease activity and severity in alopecia areata? An analytical study

BACKGROUND

Oxidative stress (OS) has been implicated as a contributory factor in the multifactorial etiopathogenesis of alopecia areata (AA). But with the existing data, it is unclear whether OS is a cause or effect of the disease state in Alopecia areata.

AIMS

To compare the OS parameters viz.malon-di-aldehyde (MDA), superoxide dismutase (SOD), total antioxidant status (TAS) in serum of patients with alopecia areata versus age and sex matched controls, and assess their correlation with the severity of the disease.

PATIENTS/METHODS

Forty clinically diagnosed patients of alopecia areata and forty (n = 40) age and sex-matched healthy controls were recruited. ELISA was used for the evaluation of MDA, and spectrophotometric method was used to evaluate serum TAS and whole blood SOD.

RESULTS

Mean serum TAS and whole blood SOD levels of cases were significantly lower than controls (p = 0.005 and p = 0.002, respectively). Mean serum MDA level of patients was significantly higher compared to controls (p = 0.001). While levels of serum TAS and whole blood SOD were found to decrease from mild to severe grades of disease (p = 0.003, p < 0.001 respectively), levels of MDA increased with increasing disease severity (p < 0.001).

CONCLUSION

The OS parameters were deranged in all subsets of AA, with the greatest derangement seen with whole blood SOD levels.

The role of oxidative stress in onychomycosis: Thiol/disulphide homeostasis

OBJECTIVES

Onychomycosis is the general term to define fungal nail infections that arise from dermatophytes, non-dermatophytic moulds and yeasts. Thiol/disulphide homeostasis is a new indicator of oxidative stress. In this study, we aimed to investigate the role of thiol/disulphide balance in the pathogenesis of onychomycosis.

METHODS

This cross-sectional study included adult patients with onychomycosis who were admitted to the dermatology department and healthy adult volunteers without any dermatologic or systemic condition. The patients and controls were evaluated in terms of native thiol, total thiol, and disulphide levels, and disulphide/native thiol, disulphide/total thiol and native thiol/total thiol ratios. The possible association between these parameters and clinical subtypes of onychomycosis and demographic characteristics was also investigated.

RESULTS

A total of 52 patients with onychomycosis and 50 healthy subjects were enrolled in the study. The patient group showed lower levels of total thiol, native thiol and native thiol/total thiol ratio, and higher ratios of disulphide/native thiol and disulphide/total thiol. No statistically significant relationship was found between the parameters, clinical subtypes of onychomycosis and demographic characteristics (p > .05).

CONCLUSION

Patients with onychomycosis showed a shifted thiol/disulphide homeostasis towards oxidative stress with a reduction in thiols and an increase in disulphide/native thiol, and disulphide/total thiol ratios. These findings may indicate the role of oxidative stress in the pathogenesis of onychomycosis.

Cross talk between oxidative stress and inflammation in alopecia areata

BACKGROUND

Although the etiopathogenesis of alopecia areata (AA) is still unclear, inflammation, oxidative stress, and subsequent DNA damage might be considered role players in disease development.

AIM

We aimed at exploring the potential link between oxidative DNA damage and inflammation in AA patients through measuring 8-hydroxy deoxyguanosine (8-OHdG), high mobility group box 1 protein (HMGB1), and one of the inflammatory mediators, C-reactive protein (CRP).

METHODS

A total of 79 subjects (49 AA patients in addition to 30 apparently healthy control subjects) were tested for serum levels of 8-OHdG, HMBG1, and CRP.

RESULTS

Compared with the control group, serum 8-OHdG, HMBG1, and CRP levels were significantly elevated in the studied patients group (0.031, <0.001, and <0.001, respectively). Moreover, logistic regression analysis revealed that disease course, serum levels of 8-OHdG, and HMBG1 were considered independent predictors for AA severity in both uni- and multivariable analyses.

CONCLUSION

Our results suggest a possible role of oxidative stress together with proinflammatory biomarkers in development of AA and their benefit in predicting a severe form of the disease.

Oxidative Stress Biomarkers and Adenosine Deaminase over the Alopecic Area of the Patients with Alopecia Areata

BACKGROUND

Alopecia areata (AA) is an autoimmune, T-cell mediated, and chronic inflammatory disorder. The pathological mechanisms of disease are unclear, but oxidative stress may be involved. To our knowledge, no studies have examined the oxidative stress levels or biomarkers within the lesional area and skin surface in patients with AA. Similarly, adenosine deaminase (ADA) has not been characterized in AA.

AIMS

Therefore, we aimed to define ADA levels and the factors involved in oxidative stress from scalp-scrapes of patients with AA.

STUDY DESIGN

Case-control study.

METHOD

A total of 60 patients (30 diagnosed AA patients and 30 healthy controls) were included in the study. ADA as well as oxidative stress factors, including malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were analyzed from scalp-scrapes in both groups and quantified by spectrophotometry.

RESULTS

Activities of SOD (p=0.000), CAT (p=0.033), and ADA (p=0.004) as well as levels of GSH (p=0.000) and MDA (p=0.032) in patients with AA were higher than the controls statistically significant.

CONCLUSION

Based on these results, factors associated with oxidative stress were elevated in AA patient scalp-scrapes compared to controls and may have a defined role the disease pathogenesis. Alterations in the activities of antioxidant enzymes from AA patient scraping samples may be a local effect of elevated oxidative stress levels. In this disease, oxidative stress may affect not only hair follicle but also any layers of the skin.

Preferential recognition of hydroxyl radical-modified superoxide dismutase by circulating autoantibodies in patients with alopecia areata

Background

Alopecia areata (AA) is a common form of localized, non-scarring hair loss. The cause of AA is unknown but reports suggest an autoimmune etiology, where oxygen free radicals play an important role.

Objective

The aim of this study was to investigate the role of a hydroxyl radicals (·OH)-modified antioxidant enzyme, superoxide dismutase (SOD), in AA autoimmunity.

Methods

SOD was modified by ·OH radicals. Binding characteristics of autoantibodies in AA patients (n=26) against ·OH-modified SOD (·OH-SOD) were evaluated by immunoassays and the results were compared with those of healthy, age-matched controls (n=30). The effects of ·OH radicals on immunoglobulin G (IgG) isolated from AA patients were studied.

Results

Highly specific binding to ·OH-SOD was observed in 32% of the samples of patient sera, whereas normal human sera showed negligible binding with either antigen. Competitive inhibition immunoassays reiterated the results from direct binding. Protein-A-purified IgG from AA patients (AA-IgG) also showed strong binding to ·OH-SOD as compared to IgG from normal human controls (p<0.001). In addition, AA-IgG from patients with alopecia universalis recognized ·OH-SOD to a greater extent than did AA-IgG from patients with the patchy, persistent type of alopecia. Furthermore, sera from AA patients had lower levels of SOD activity as compared to control sera.

Conclusion

This is the first report showing an association between ·OH-modified SOD and AA. These novel results demonstrate that ·OH radical-mediated changes in SOD present unique neo-epitopes that might contribute to antigen-driven antibody induction in AA.

Biochemical and immunological studies on erythrocytes superoxide dismutase modified by nitric oxide in patients with alopecia areata: Implications in alopecia patchy persistent and alopecia universalis

Alopecia areata (AA) is a non-scarring hair loss disorder that ranges in severity from patchy loss of scalp hair (AA patchy persistent; AAP) to loss of all scalp and body hair (alopecia universalis; AU). The cause of AA is unknown but most evidences support that AA has an autoimmune etiology, where free radicals play an important role. This study was undertaken to investigate the role of nitric oxide (NO) modified erythrocytes superoxide dismutase (eSOD) in AA. Data revealed that NO-induced damage in eSOD caused alteration in hydrophobic or aromatic amino acids and protein carbonyl contents. NO-specific quencher, carboxyl-PTIO further reiterates NO-modifications. Specificity of antibodies from AA patients (n=26) was analyzed toward NO-modified eSOD (NO-eSOD) and their results were compared with healthy controls (n=30). Protein-A purified IgG of AA patients (AA-IgG) showed strong binding to NO-eSOD in comparison with IgG from controls. In addition, AA-IgG from patients with AU recognized NO-eSOD in a greater extent as compared to AA-IgG from patients with AAP. Furthermore, AU patients' sera contained higher levels of NO or carbonyl contents and lower levels of SOD activity compared with AAP patients' or control sera. In conclusion, this is the first study to demonstrate the role of NO-modified-eSOD in AA. Our novel results conclude that perturbations in SOD by NO presenting unique neo-epitopes that might be one of the factors for the antigen driven antibodies induction in AA. Preferential binding of NO-eSOD by AA-IgG pointed out the likely role of NO-eSOD in the initiation/progression of AA.

Oxidative stress in alopecia areata: a case-control study

BACKGROUND

Increased reactive oxygen species (ROS) and lipid peroxidation are seen in many dermatologic disorders, including atopic dermatitis, psoriasis, vitiligo, acne vulgaris, pemphigus vulgaris, and lichen planus. In alopecia areata (AA), there is increased production of ROS from perifollicular inflammatory cells.

OBJECTIVE

The aim of this study was to determine the oxidative stress index (OSI) and lipid peroxidation by studying serum total oxidant capacity (TOC), total antioxidant capacity (TAC), and malondialdehyde (MDA) values in AA patients.

METHODS

The study included 35 AA patients and a control group consisting of 30 age- and sex-matched healthy volunteers. The serum TOC, TAC, and MDA values were measured, and the OSIs were calculated and compared in both groups.

RESULTS

The mean serum TOC (p < 0.001), MDA (p < 0.001), and OSI (p < 0.001) values were found to be significantly higher in AA patients than in the control group. The mean serum TAC value was significantly lower (p < 0.05) in cases than in controls. Significantly higher MDA (p < 0.001), TOC (p < 0.001), and OSI values (p < 0.001) and lower TAC values (p < 0.01) were found in severe AA than in mild or moderate AA.

CONCLUSION

The demonstrated results confirmed the presence of oxidative stress and lipid peroxidation in AA. Whether these changes play a role in disease pathogenesis or result from the inflammatory process requires further investigation.