Increased oxidative stress in pemphigus vulgaris is related to disease activity and HLA-association

Identification of Six microRNAs as Potential Biomarkers for Pemphigus Vulgaris: From Diagnosis to Pathogenesis

BACKGROUND

Pemphigus vulgaris (PV) is a potentially fatal autoimmune bullous disease. The role of microRNA (miRNA, miR) in the diagnosis and pathogenesis of PV remains unknown. This study aims to provide potential miRNA biomarkers for PV diagnosis and therapy options.

METHODS

Serum samples were obtained from 22 PV patients, 15 mucous membrane pemphigoid (MMP) patients, and 10 normal controls (NC). Total RNA was extracted from the serum samples, and 12 selected miRNAs were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Bioinformatic analyses including target gene prediction and enrichment analysis were performed.

RESULTS

Twelve miRNAs were increased in the serum of the PV group compared with the NC group, in which six miRNAs had good efficacy to diagnose PV from MMP with the area under the receiver operator characteristic curves of 0.970 to 0.988. A series test for the combination of miR-584-5p and miR-155-5p reached the sensitivity and specificity of 95.5% and 100%. Bioinformatic analysis revealed target gene enrichment in the cell adhesion pathways, immune-relating pathways, and P38 mitogen-activated protein kinases signaling pathway.

CONCLUSION

The study provides new insights and targets of miRNAs for the precise diagnosis and the exploration of pathogenesis for PV, which may serve as a reference for further research into autoimmune bullous diseases.

Focus on the Contribution of Oxidative Stress in Skin Aging

Skin aging is one of the most evident signs of human aging. Modification of the skin during the life span is characterized by fine lines and wrinkling, loss of elasticity and volume, laxity, rough-textured appearance, and pallor. In contrast, photoaged skin is associated with uneven pigmentation (age spot) and is markedly wrinkled. At the cellular and molecular level, it consists of multiple interconnected processes based on biochemical reactions, genetic programs, and occurrence of external stimulation. The principal cellular perturbation in the skin driving senescence is the alteration of oxidative balance. In chronological aging, reactive oxygen species (ROS) are produced mainly through cellular oxidative metabolism during adenosine triphosphate (ATP) generation from glucose and mitochondrial dysfunction, whereas in extrinsic aging, loss of redox equilibrium is caused by environmental factors, such as ultraviolet radiation, pollution, cigarette smoking, and inadequate nutrition. During the aging process, oxidative stress is attributed to both augmented ROS production and reduced levels of enzymatic and non-enzymatic protectors. Apart from the evident appearance of structural change, throughout aging, the skin gradually loses its natural functional characteristics and regenerative potential. With aging, the skin immune system also undergoes functional senescence manifested as a reduced ability to counteract infections and augmented frequency of autoimmune and neoplastic diseases. This review proposes an update on the role of oxidative stress in the appearance of the clinical manifestation of skin aging, as well as of the molecular mechanisms that underline this natural phenomenon sometimes accelerated by external factors.

Genetic polymorphism of glutathione S-transferases (GSTM1, GSTT1, and GSTP1) in patients with bullous pemphigoid in a Polish population

Introduction. Bullous pemphigoid (BP) is one of the most common bullous diseases with an autoimmune background. The etiology and pathogenesis of BP are believed to be influenced not only by environmental, genetic, and immunological factors as well as by oxidative stress. BP is observed more frequently in elderly patients. Additionally, more potent oxidative stress is observed just in old age. Glutathione S-transferases (GSTs) play key roles in the detoxification of xenobiotics, metabolism of endogenous substrates, and the defense against oxidative stress. The present study examines whether polymorphism of genes encoding three selected GSTs (GSTM1, GSTT1, and GSTP1) might be associated with a higher risk for BP.

Materials and methods. The study involved 71 patients with BP and 100 healthy volunteers from a Polish population. The presence of the deletion type polymorphism for GSTM1 and GSTT1 was confirmed by multiplex PCR. The Ile105Val GSTP1 polymorphism was analyzed by PCR-RFLP.

Results. It was observed that the combination of GSTM1 null/GSTT1 null/GSTP1 Ile/Val, Val/Val genotypes occurred more frequently in patients with BP (8.5%) than in controls (4.0%). The odds ratio for carriers of GSTM1 null/GSTT1 null/ GSTP1 Ile/Val, Val/Val genotypes was 2.22 (95% CI 0.60–8.16; p = 0.3727), but was not statistically significant.

Conclusions. The combination of GSTM1 null, GSTT1 null, GSTP1 Ile/Val, Val/Val genotypes might be related to a greater risk of BP in a Polish population. However, future studies including more individuals are required to confirm this.

Serum and tissue levels of coenzyme Q10 in pemphigus vulgaris

BACKGROUND

Pemphigus vulgaris (PV) is a debilitating autoimmune blistering disease of the skin and mucous membranes. It occurs due to the action of autoantibodies against various keratinocyte self-antigens. Anti-mitochondrial autoantibodies are detected in patients with PV. Coenzyme Q10 (CoQ10) is a member of the mitochondrial respiratory chain involved in cellular metabolism, including apoptosis. This study aimed to assess the serum and tissue levels of CoQ10 of patients with PV and healthy controls to determine its relevance to the disease pathogenesis.

METHODS

In this case-control study, 20 patients with PV and 20 healthy controls were included. Blood and skin samples were collected for the measurement of CoQ10 levels using ELISA.

RESULTS

CoQ10 was significantly lower in both serum and tissue of patients with PV compared with controls (p = 0.001). Similar results were found when gender subgroups were separately compared. A significant positive correlation was found between serum and tissue CoQ10 levels in controls (p = 0.019, r = 0.521), but not in patients with PV.

CONCLUSION

CoQ10 appears to be one of the parameters affected by the autoimmune response in PV, which may contribute to the tissue damage caused by autoantibodies. The absence of a significant correlation between CoQ10 level and disease severity or duration may be caused by the complex pathophysiological process in PV with multiple autoantibodies against different keratinocyte antigens.

Current evidence to support the therapeutic potential of flavonoids in oxidative stress-related dermatoses

BACKGROUND

Skin, as a crucial external defense organ, is more vulnerable to oxidative stress (OS) insult, reactive oxygen species (ROS)-mediated OS in particular. OS results from a redox imbalance caused by various extrinsic stimuli and occurs once the oxidants production overwhelming the antioxidants capacity, through mediating in DNA damage, lipid peroxidation (LPO), protein oxidation and a serial of signaling pathways activation/inactivation, thereby offering favorable conditions for the occurrence and development of numerous diseases especially some dermatoses, e.g. psoriasis, vitiligo, skin photodamage, skin cancer, systemic sclerosis (SSc), chloasma, atopic dermatitis (AD), pemphigus, etc. Targeting OS molecular mechanism, a variety of anti-OS agents emerge, in which flavonoids, natural plant extracts, stand out.

OBJECTIVES

To discuss the possible mechanisms of OS mediating in dermatoses and summarize the properties of flavonoids as well as their applications in OS-related skin disorders.

METHODS

Published papers on flavonoids and OS-related skin diseases were collected and reviewed via database searching on PubMed, MEDLINE and Embase, etc.

RESULTS

It has been confirmed that flavonoids, belonging to polyphenols, are a class of plant secondary metabolites widely distributed in various plants and possess diverse bioactivities especially their potent antioxidant capacity. Moreover, flavonoids benefit to suppress OS via eliminating free radicals and mediating the corresponding signals, further excellently working in the prevention and management of OS-related skin diseases.

CONCLUSION

Flavonoids have the potential therapeutic effects on oxidative stress-related dermatoses. However, more studies on specific mechanism as well as the dosage of flavonoids are needed in future.

Evolving Mechanisms in the Pathophysiology of Pemphigus Vulgaris: A Review Emphasizing the Role of Desmoglein 3 in Regulating p53 and the Yes-Associated Protein

The immunobullous condition Pemphigus Vulgaris (PV) is caused by autoantibodies targeting the adhesion proteins of desmosomes, leading to blistering in the skin and mucosal membrane. There is still no cure to the disease apart from the use of corticosteroids and immunosuppressive agents. Despite numerous investigations, the pathological mechanisms of PV are still incompletely understood, though the etiology is thought to be multifactorial. Thus, further understanding of the molecular basis underlying this disease process is vital to develop targeted therapies. Ample studies have highlighted the role of Desmoglein-3 (DSG3) in the initiation of disease as DSG3 serves as a primary target of PV autoantibodies. DSG3 is a pivotal player in mediating outside-in signaling involved in cell junction remodeling, cell proliferation, differentiation, migration or apoptosis, thus validating its biological function in tissue integrity and homeostasis beyond desmosome adhesion. Recent studies have uncovered new activities of DSG3 in regulating p53 and the yes-associated protein (YAP), with the evidence of dysregulation of these pathways demonstrated in PV. The purpose of this review is to summarize the earlier and recent advances highlighting our recent findings related to PV pathogenesis that may pave the way for future research to develop novel specific therapies in curing this disease.

Oxidative Stress in Cutaneous Lichen Planus-A Narrative Review

Lichen planus (LP) is a chronic, immune-mediated inflammatory skin condition that mainly affects the skin (cutaneous LP, CLP) and oral mucosa (oral LP, OLP). However, the mechanisms involved in the pathogenesis of the disease are not fully elucidated. Over time, several theories that could explain the appearance of LP lesions have been postulated. The key players in LP pathogenesis are the inflammatory infiltrate consisting of T cells and the proinflammatory cytokines. The cytokines stimulate the production of reactive oxygen species that induce cell apoptosis, a defining element encountered in LP. The lead inquiry triggered by this revolves around the role of oxidative stress in LP development. There are currently numerous studies showing the involvement of oxidative stress in OLP, but in terms of CLP, data are scarce. In this review, we analyze for the first time the currently existing studies on oxidative stress in CLP and summarize the results in order to assess the role of oxidative stress in skin lesions offering a fresher updated perspective.

Oxidative Stress-Mediated YAP Dysregulation Contributes to the Pathogenesis of Pemphigus Vulgaris

Pemphigus Vulgaris (PV) is a life-threatening autoimmune disease manifested with blisters in the skin and mucosa and caused by autoantibodies against adhesion protein desmoglein-3 (Dsg3) expressed in epithelial membrane linings of these tissues. Despite many studies, the pathogenesis of PV remains incompletely understood. Recently we have shown Dsg3 plays a role in regulating the yes-associated protein (YAP), a co-transcription factor and mechanical sensor, and constraining reactive oxygen species (ROS). This study investigated the effect of PV sera as well as the anti-Dsg3 antibody AK23 on these molecules. We detected elevated YAP steady-state protein levels in PV cells surrounding blisters and perilesional regions and in keratinocytes treated with PV sera and AK23 with concomitant transient ROS overproduction. Cells treated with hydrogen peroxide also exhibited augmented nuclear YAP accompanied by reduction of Dsg3 and α-catenin, a negative regulator of YAP. As expected, transfection of α-catenin-GFP plasmid rendered YAP export from the nucleus evoked by hydrogen peroxide. In addition, suppression of total YAP was observed in hydrogen peroxide treated cells exposed to antioxidants with enhanced cell-cell adhesion being confirmed by decreased fragmentation in the dispase assay compared to hydrogen peroxide treatment alone. On the other hand, the expression of exogenous YAP disrupted intercellular junction assembly. In contrast, YAP depletion resulted in an inverse effect with augmented expression of junction assembly proteins, including Dsg3 and α-catenin capable of abolishing the effect of AK23 on Dsg3 expression. Finally, inhibition of other kinase pathways, including p38MAPK, also demonstrated suppression of YAP induced by hydrogen peroxide. Furthermore, antioxidant treatment of keratinocytes suppressed PV sera-induced total YAP accumulation. In conclusion, this study suggests that oxidative stress coupled with YAP dysregulation attributes to PV blistering, implying antioxidants may be beneficial in the treatment of PV.

Redox Enzymes of the Thioredoxin Family as Potential and Novel Markers in Pemphigus

Pemphigus vulgaris (PV) is a severe autoimmune blistering disease affecting both skin and mucous membranes. Its pathogenesis is related to IgG autoantibodies primarily targeting the cellular adhesion protein desmoglein (Dsg) 3, one of the major desmosome components. Impaired redox regulation is considered a major player in the pathogenesis of autoimmune diseases such as pemphigus by enhancing inflammation and breakdown of immunological tolerance by structural protein modifications. Despite many recent advances, local and systemic redox profiles that characterize the immune response in pemphigus are virtually unknown but potentially crucial in further advancing our understanding of redox-dependent modifications that eventually lead to clinical manifestation. Here, we have analyzed the individual expression pattern of four major redox enzymes that are members of the thioredoxin (Trx) fold superfamily (peroxiredoxins (Prxs) 1 and 4, glutaredoxin (Grx) 2, and Trx1) in serum and PBMCs as well as their distribution in the skin of pemphigus patients compared to healthy controls. We show that in groups of five pemphigus patients, Prx1 is upregulated in both serum and PBMCs, while its epithelial distribution remains within the spinous epithelial layer. Expression of Grx2 and Prx4 is both reduced in serum and PBMCs, while their distinct and similar expression in the skin changes from an even distribution throughout the basal layer (healthy) to ubiquitous nuclear localization in pemphigus patients. In PV patients, Trx1 is secreted into serum, and cellular distribution appears membrane-bound and cytosolic compared to healthy controls. We furthermore showed that a 3D ex vivo human skin model can indeed be used to reproduce similar changes in the protein levels and distribution of redox enzymes by application of cold atmospheric plasma. Deciphering the relationship between redox enzyme expression and autoimmunity in the context of pemphigus could be critical in elucidating key pathogenic mechanisms and developing novel interventions for clinical management.

The relationship between non-segmental Vitiligo, HLA genotype and oxidative stress

BACKGROUND

Vitiligo is an autoimmune disease characterised by acquired loss of melanocytes. Although the pathogenesis of vitiligo remains unknown, oxidative stress and autoimmune dysregulations are considered to play a role.

OBJECTIVE

The aim of this study was to evaluate the HLA profile and total antioxidant capacity (TAC) and their relationship to clinical characteristic of vitiligo patients.

METHODS

Ninety-one vitiligo patients and 100 healthy controls were included in the study. We analysed HLA allele frequencies using sequence-specific oligonucleotide Prob (SSOP) method. Serum total antioxidant capacity (TAC) levels were measured and compared between vitiligo patients and controls.

RESULTS

HLA-A*02 allele frequency was increased (OR = 1.6, CI = 1.12-2.24, P = .009), HLA-A*11 (OR = 0.46, CI = 0.32-0.91, P = .019) and HLA-DRB1*01 (OR = 0.39, CI = 0.16-0.92, P = .029) frequencies were decreased in vitiligo patients. HLA-A*02 allele especially increased the risk of late onset (Vitiligo onset >30 years of age) vitiligo (OR:3.67, 95% CI: 1.63-8.26, P = .002). Serum TAC levels were similar between vitiligo patients and healthy controls but TAC levels were significantly lower in patients who did not have an HLA-DRB1*01 allele (1.52 vs 1.61, P = .033).

CONCLUSION

Our study showed that HLA-A*02 increases, HLA-A*11 and HLA-DRB1*01 decreases vitiligo susceptibility in Turkish patients as well as a possible relationship between HLA and TAC.

The Evaluation of Serum Lipids Profile in Patients with Pemphigus Vulgaris: A Case-Control Study

Background

Pemphigus vulgaris (PV) is a chronic autoimmune disease. Dyslipidemia, increased risk of atherosclerosis and higher cardiovascular morbidity, and mortality have been reported in several autoimmune conditions. It has been hypothesised that there might be an association between dyslipidemia and PV. Therefore, the objective of this study was to compare the serum lipid profile of patients with PV with healthy controls.

Methods

This case-control study was carried out on 113 patients with PV and 100 healthy controls. Total cholesterol, high-density lipoprotein (HDL) and triglycerides (TG) levels were measured and low-density lipoprotein (LDL), non-HDL cholesterol (non-HDL-C) and atherogenic index of plasma (AIP) were calculated. Chi-squared test and independent Student t-test (or their alternatives) were used for group comparison.

Results

The mean age and BMI of patients and controls were 47.7 ± 14.5 and 28 ± 6.2 and, 44.5 ± 18.5 and 25.5 ± 5.1, respectively. Total cholesterol, LDL, HDL, non-HDL-C and TG were statistically different between the two groups (P values < 0.001; < 0.001; < 0.001; < 0.001 and 0.021, respectively). However, AIP was not significantly different (P-value = 0.752).

Conclusion

The serum lipid profile was significantly higher in PV patients compared to healthy controls. Therefore, PV patients may be more prone to develop atherosclerosis and this finding can be important in the overall management of these patients.

Recent advances in the understanding and treatment of pemphigus and pemphigoid

Pemphigus and pemphigoid are characterized as autoimmune blistering diseases in which immunoglobulin G autoantibodies cause blisters and erosions of the skin or mucosa or both. Recently, understanding of the pathophysiology of pemphigus and pemphigoid has been furthered by genetic analyses, characterization of autoantibodies and autoreactive B cells, and elucidation of cell–cell adhesion between keratinocytes. For the management of pemphigus and pemphigoid, the administration of systemic corticosteroids still represents the standard treatment strategy; however, evidence of the efficacy of therapies not involving corticosteroids, such as those employing anti-CD20 antibodies, is increasing. The goal should be to develop antigen-specific immune suppression-based treatments.

Autoantibody Signaling in Pemphigus Vulgaris: Development of an Integrated Model

Pemphigus vulgaris (PV) is an autoimmune skin blistering disease effecting both cutaneous and mucosal epithelia. Blister formation in PV is known to result from the binding of autoantibodies (autoAbs) to keratinocyte antigens. The primary antigenic targets of pathogenic autoAbs are known to be desmoglein 3, and to a lesser extent, desmoglein 1, cadherin family proteins that partially comprise the desmosome, a protein structure responsible for maintaining cell adhesion, although additional autoAbs, whose role in blister formation is still unclear, are also known to be present in PV patients. Nevertheless, there remain large gaps in knowledge concerning the precise mechanisms through which autoAb binding induces blister formation. Consequently, the primary therapeutic interventions for PV focus on systemic immunosuppression, whose side effects represent a significant health risk to patients. In an effort to identify novel, disease-specific therapeutic targets, a multitude of studies attempting to elucidate the pathogenic mechanisms downstream of autoAb binding, have led to significant advancements in the understanding of autoAb-mediated blister formation. Despite this enhanced characterization of disease processes, a satisfactory explanation of autoAb-induced acantholysis still does not exist. Here, we carefully review the literature investigating the pathogenic disease mechanisms in PV and, taking into account the full scope of results from these studies, provide a novel, comprehensive theory of blister formation in PV.

Effect of ultraviolet irradiation on free radical scavenging activity of immunosuppressants used in lung transplantation and comparative electron paramagnetic resonance study of kinetics of their interactions with model free radicals

WHAT IS KNOWN AND OBJECTIVE

The immunosuppressive drugs used in solid organ transplantation or autoimmunological processes were studied by electron paramagnetic resonance (EPR) spectroscopy to estimate their free radical scavenging activity. The interactions of immunosuppressants with free radicals were examined by an X-band (9.3 GHz) EPR spectroscopy and a model of DPPH free radicals.

METHODS

The EPR spectra of DPPH and DPPH interacting with individual drugs were compared. Kinetic studies were performed, and the effect of ultraviolet (UV) irradiation on the free radical scavenging activity of the tested drugs was determined.

RESULTS AND DISCUSSION

The free radical scavenging activity of non-irradiated drugs decreased in the order: rapamycin > mycophenolate mofetil > ciclosporin > tacrolimus. UV irradiation increased the free radical scavenging activity of all the tested immunosuppressive drugs, and the effect was highest for tacrolimus. For the non-irradiated samples, the speed of free radical interactions decreased in the order: ciclosporin > tacrolimus > mycophenolate mofetil > rapamycin. UV irradiation only slightly affected the speed of interactions of the immunosuppressive drugs with the model DPPH free radicals.

WHAT IS NEW AND CONCLUSION

Electron paramagnetic resonance spectroscopy is useful for obtaining information on interactions of immunosuppressive drugs with free radicals. We hypothesized that the long-term immunosuppressive effects of these drugs after transplantation or during autoimmune disorders may be mediated by anti-inflammatory action in addition to the known receptor/cell cycle inhibition.

Pemphigus

Pemphigus is a group of IgG-mediated autoimmune diseases of stratified squamous epithelia, such as the skin and oral mucosa, in which acantholysis (the loss of cell adhesion) causes blisters and erosions. Pemphigus has three major subtypes: pemphigus vulgaris, pemphigus foliaceus and paraneoplastic pemphigus. IgG autoantibodies are characteristically raised against desmoglein 1 and desmoglein 3, which are cell-cell adhesion molecules found in desmosomes. The sites of blister formation can be physiologically explained by the anti-desmoglein autoantibody profile and tissue-specific expression pattern of desmoglein isoforms. The pathophysiological roles of T cells and B cells have been characterized in mouse models of pemphigus and patients, revealing insights into the mechanisms of autoimmunity. Diagnosis is based on clinical manifestations and confirmed with histological and immunochemical testing. The current first-line treatment is systemic corticosteroids and adjuvant therapies, including immunosuppressive agents, intravenous immunoglobulin and plasmapheresis. Rituximab, a monoclonal antibody against CD20⁺ B cells, is a promising therapeutic option that may soon become first-line therapy. Pemphigus is one of the best-characterized human autoimmune diseases and provides an ideal paradigm for both basic and clinical research, especially towards the development of antigen-specific immune suppression treatments for autoimmune diseases.