Potential pathogenic mechanisms involved in the association between lichen planus and hepatitis C virus infection

Oral Lichen Planus: An Updated Review of Etiopathogenesis, Clinical Presentation, and Management

Lichen planus (LP) is a chronic idiopathic immune-mediated inflammatory condition. LP is a heterogeneous disease with varied clinical presentations having different natural history, prognosis, sequelae, and outcomes. It can affect skin, hair, nails, and mucosae. Mucosal LP (including oral LP) tends to be persistent and resistant to treatment, compared to cutaneous LP. Oral LP (OLP) is broadly divided into two main categories: hyperkeratotic (usually asymptomatic) and erosive (commonly symptomatic). It can present with symptoms including odynophagia, dysphagia, dysgeusia, and sensitivity to hot spicy foods. Apart from the superficial epidermal changes, which vary with the type of clinical presentation, histopathologically oral LP shows a unifying similar and consistent feature of a lichenoid interface dermatitis. Recently, researchers have highlighted the critical role played by IL-17 in the pathogenesis of OLP. World Health Organization has categorized oral LP as one of the oral potentially malignant disorders (OPMD), albeit with a low risk of malignant transformation. Also, in the last couple of years there have been various reports on the usage of newer drugs like anti-IL17, anti-IL12/23, anti-IL 23, PDE4 inhibitors, and JAK inhibitors in the management of refractory OLP. The principal aim of treatment still remains to resolve the symptoms, prolong the symptoms free period, and reduce the risk of potential malignant transformation. We have described many new revelations made in recent times regarding the etiopathogenesis, associated conditions as well as management of OLP. Thus, the objective of this review is to present a comprehensive up-to-date knowledge including the recent advances made regarding OLP.

[Esophageal Lichen Planus - An Underdiagnosed Disease]

An involvement of the esophagus in patients with lichen planus was described for the first time in 1982. Ever since, it has been seen as a rarity. However, studies over the last 10 years have shown a higher prevalence than expected. It may even be supposed that esophageal lichen planus (ELP) is more common than eosinophilic esophagitis. ELP mostly affects middleaged women. The principal symptom is dysphagia. Endoscopically, ELP is characterized by denudation and tearing of the mucosa, trachealization and hyperkeratosis and esophageal stenosis may occur in patients with long courses of the disease. Histologic findings including mucosal detachment, T-lymphocytic infiltrate, intraepithelial apoptosis (civatte bodies) and dyskeratosis are crucial. Direct immunofluorescence shows fibrinogen deposits along the basement membrane zone. So far, there is no well-established therapy but a treatment with topic steroids is effective in 2/3 of the patients. Common therapy of lichen planus of the skin seems to be ineffective for treatment of ELP. Symptomatic esophageal stenosis should be endoscopically dilated. ELP joins the group of "new" immunologic diseases of the esophagus.

Der Lichen planus des Ösophagus – Eine unterschätzte Erkrankung

Eine Beteiligung des Ösophagus bei der Hauterkrankung Lichen planus wurde erstmals 1982 beschrieben und fast 30 Jahre lang als eine Rarität angesehen. Untersuchungen der letzten 10 Jahre aber zeigen, dass diese Erkrankung weniger selten ist als angenommen. Es ist sogar anzunehmen, dass der ösophageale Lichen planus (Esophageal Lichen planus, ELP) häufiger ist als die Eosinophile Ösophagitis (EoE). Die Ösophagusbeteiligung betrifft meist Frauen im mittleren Alter. Das Hauptsymptom ist eine Dysphagie. Endoskopisch erkennt man in der Speiseröhre eine charakteristische Schleimhautablösung, eine Trachealisierung, und gelegentlich Hyperkeratosen und bei langem Bestehen auch Stenosen. Wegweisend ist die Histologie mit einer subepithelialen Ablösung sowie einem bandförmigen Infiltrat aus T-Lymphozyten, dem Nachweis von apoptotischen Keratinozyten (Civatte Bodies) und Dyskeratosen. Die direkte Immunfluoreszenz zeigt Fibrinogen-Ablagerungen entlang der Basalmembran. Eine etablierte Therapie gibt es bisher nicht. Die Behandlung mit topischen Steroiden ist in ⅔ der Fälle wirksam. Eine Therapie wie beim klassischen Lichen planus scheint unwirksam zu sein. Bei symptomatischen Stenosen kann eine Dilatation indiziert sein. Der ELP reiht sich in die Gruppe der „neuen“ immunologisch vermittelten Erkrankungen des Ösophagus ein.

Esophageal lichen planus: Current knowledge, challenges and future perspectives

Lichen planus (LP) is a frequent, chronic inflammatory disease involving the skin, mucous membranes and/or skin appendages. Esophageal involvement in lichen planus (ELP) is a clinically important albeit underdiagnosed inflammatory condition. This narrative review aims to give an overview of the current knowledge on ELP, its prevalence, pathogenesis, clinical manifestation, diagnostic criteria, and therapeutic options in order to provide support in clinical management. Studies on ELP were collected using PubMed/Medline. Relevant clinical and therapeutical characteristics from published patient cohorts including our own cohort were extracted and summarized. ELP mainly affects middle-aged women. The principal symptom is dysphagia. However, asymptomatic cases despite progressed macroscopic esophageal lesions may occur. The pathogenesis is unknown, however an immune-mediated mechanism is probable. Endoscopically, ELP is characterized by mucosal denudation and tearing, trachealization, and hyperkeratosis. Scarring esophageal stenosis may occur in chronic courses. Histologic findings include mucosal detachment, T-lymphocytic infiltrations, epithelial apoptosis (Civatte bodies), dyskeratosis, and hyperkeratosis. Direct immuno-fluorescence shows fibrinogen deposits along the basement membrane zone. To date, there is no established therapy. However, treatment with topical steroids induces symptomatic and histologic improvement in two thirds of ELP patients in general. More severe cases may require therapy with immunosuppressors. In symptomatic esophageal stenosis, endoscopic dilation may be necessary. ELP may be regarded as a precancerous condition as transition to squamous cell carcinoma has been documented in literature. ELP is an underdiagnosed yet clinically important differential diagnosis for patients with unclear dysphagia or esophagitis. Timely diagnosis and therapy might prevent potential sequelae such as esophageal stenosis or development of invasive squamous cell carcinoma. Further studies are needed to gain more knowledge about the pathogenesis and treatment options.

Thiol-Disulfide Homeostasis in Skin Diseases

Oxidative stress represents the imbalance between oxidants and antioxidants and has been associated with a wide range of diseases. Thiols are the most important compounds in antioxidant defense. There is an equilibrium between thiols and their oxidized forms, disulfides, known as dynamic thiol-disulfide homeostasis (TDH). In 2014, Erel and Neselioglu developed a novel automated assay to measure thiol and disulfide levels. Subsequently, many researchers have used this simple, inexpensive and fast method for evaluating TDH in various disorders. We have reviewed the literature on the role of TDH in skin diseases. We identified 26 studies that evaluated TDH in inflammatory diseases (psoriasis, seborrheic dermatitis, atopic dermatitis, vitiligo, acne vulgaris and rosacea), allergic diseases (acute and chronic urticaria) and infectious diseases (warts, pityriasis rosea and tinea versicolor). The results are heterogeneous, but in most cases indicate changes in TDH that shifted toward disulfides or toward thiols, depending on the extent of oxidative damage.

A Review on Extrahepatic Manifestations of Chronic Hepatitis C Virus Infection and the Impact of Direct-Acting Antiviral Therapy

Extrahepatic manifestations are a feature of chronic hepatitis C virus (HCV) infection. In the course of chronic HCV infection, about 70% of patients have one or more extrahepatic manifestations. The latter are often the first and only clinical sign of infection. Experimental and clinical data support a causal association for many extrahepatic manifestations and HCV infection, which include mixed cryoglobulinemia, non-Hodgkin lymphomas (NHL), cardiovascular disease, insulin resistance, type 2 diabetes, neurological and psychiatric disease and other rheumatic diseases. All these extrahepatic conditions influence the morbidity, quality of life and mortality of HCV-infected patients. Currently, interferon-free therapeutic regimens with direct-acting antiviral agents (DAA) offer the possibility of treatment to almost the entire infected population, irrespective of stage of cirrhosis and associated serious comorbidities, always maintaining a high efficacy and tolerability. Several studies have shown a close association between HCV clearance by DAAs and an improvement or reduction in the risk of extrahepatic manifestations. Patients with HCV after a sustained virologic response (SVR) by DAA treatment have a lower risk than non-responders of developing cryoglobulinemic vasculitis and B-cell non-Hodgkin’s lymphomas. Furthermore, the SVR by DAA also reduces the risk of acute coronary syndrome, cardiovascular disease, insulin resistance and type 2 diabetes, and it improves atherosclerosis. HCV clearance by DAA also improves the quality of life and survival of patients with chronic HCV infection with associated extrahepatic diseases. Thus, DAAs should be initiated as early as possible in HCV patients with extrahepatic manifestations.

Therapies with Antioxidant Potential in Psoriasis, Vitiligo, and Lichen Planus

Oxidative stress plays an important pathogenetic role in many chronic inflammatory diseases, including those of dermatological interest. In particular, regarding psoriasis, vitiligo, and lichen planus, excess reactive oxygen species and a decline in endogenous antioxidant systems are observed. In this regard, treatments with antioxidant properties could be appropriate therapeutic options. To date, clinical trials in dermatology on these treatments are limited. We reviewed the available studies on the efficacy of antioxidant therapies in psoriasis, vitiligo, and lichen planus. The role of herbal derivatives, vitamins, and trace elements was analyzed. The antioxidant properties of conventional therapies were also evaluated. Data from the literature suggest that antioxidants might be useful, but available studies on this topic are limited, heterogeneous, not completely standardized, and on small populations. Furthermore, in most cases, antioxidants alone are unable to induce significant clinical changes, except perhaps in mild forms, and must be used in conjunction with standard drug treatments to achieve measurable results. Further studies need to be conducted, considering larger populations and using internationally validated scales, in order to compare the results and clinical efficacy.

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.

New markers of oxidative stress in lichen planus and the influence of hepatitis C virus infection - a pilot study

INTRODUCTION

Lichen planus (LP) is a mucocutaneous T-cell mediated disorder of unknown etiology. There is growing evidence that oxidative stress is an important player in the pathogenesis of LP. Therefore, we have investigated oxidative stress markers in LP and the influence of hepatitis C virus (HCV) infection, a frequently associated condition, on oxidative stress in LP patients.

METHOD

We have determined the serum levels of 4- hydroxynonenal (4-HNE) and symmetric dimethylarginine (SDMA), as markers of oxidative stress, and total antioxidant capacity (TAC), as a marker of the antioxidant defence, in 4 groups: group A - HCV positive patients with LP (n=12), group B - HCV positive patients without LP (n=12), group C - HCV negative patients with LP (n=31) and group D - control group (n=26).

RESULTS

In LP patients, we have identified an increased level of lipid peroxidation (4-HNE - group A - 8.41±1.11 µg/mL, group B - 7.97±2.17 µg/mL, group C - 7.81±1.96 µg/mL and group D - 6.15±1.17 µg/mL) and alterations in arginine methylation (SDMA - group A - 1.10±0.24 µmol/L, group B - 1.03±0.16 µmol/L, group C - 0.84±0.19 µmol/L and group D - 0.50±0.06 µmol/L) associated with a diminished antioxidant defence (TAC - group A - 234,50±49,96, µmol/L group B - 255,83±41,41 µmol/L, group C - 269,83±43,33 µmol/L and group D - 316,46 ±29,33 µmol/L), processes augmented by the association with HCV infection.

CONCLUSION

There is an imbalance between oxidants and antioxidants in patients with LP, an imbalance that is augmented by the presence of HCV infection. SDMA could be regarded as a novel biomarker of oxidative stress among these patients. To the best of our knowledge this is the first study to investigate the influence of HCV infection on oxidative stress in LP patients.

[Esophageal Lichen Planus - an Underdiagnosed Disease]

An involvement of the esophagus in patients with lichen planus was described for the first time in 1982. Ever since, it has been seen as a rarity. However, studies over the last 10 years have shown a higher prevalence than expected. It may even be supposed that esophageal lichen planus (ELP) is more common than eosinophilic esophagitis. ELP mostly affects middle-aged women. The principal symptom is dysphagia. Endoscopically, ELP is characterized by denudation and tearing of the mucosa, trachealization and hyperkeratosis and esophageal stenosis may occur in patients with long courses of the disease. Histologic findings including mucosal detachment, T-lymphocytic infiltrate, intraepithelial apoptosis (civatte bodies) and dyskeratosis are crucial. Direct immunofluorescence shows fibrinogen deposits along the basement membrane zone. So far, there is no well-established therapy but a treatment with topic steroids is effective in 2/3 of the patients. Common therapy of lichen planus of the skin seems to be ineffective for treatment of ELP. Symptomatic esophageal stenosis should be endoscopically dilated. ELP joins the group of "new" immunologic diseases of the esophagus.

Oral lichen planus: a microbiologist point of view

Oral lichen planus (OLP) is a chronic disease of uncertain etiology, although it is generally considered as an immune-mediated disease that affects the mucous membranes and even the skin and nails. Over the years, this disease was attributed to a variety of causes, including different types of microorganisms. This review analyzes the present state of the art of the disease, from a microbiological point of view, while considering whether or not the possibility of a microbial origin for the disease can be supported. From the evidence presented here, OLP should be considered an immunological disease, as it was initially proposed, as opposed to an illness of microbiological origin. The different microorganisms so far described as putative disease-causing agents do not fulfill Koch’s postulates; they are, actually, not the cause, but a result of the disease that provides the right circumstances for microbial colonization. This means that, at this stage, and unless new data becomes available, no microorganism can be envisaged as the causative agent of lichen planus.

Proteomic Technology "Lens" for Epithelial-Mesenchymal Transition Process Identification in Oncology

The epithelial-mesenchymal transition (EMT) is a complex transformation process that induces local and distant progression of many malignant tumours. Due to its complex array of proteins that are dynamically over-/underexpressed during this process, proteomic technologies gained their place in the EMT research in the last years. Proteomics has identified new molecular pathways of this process and brought important insights to develop new therapy targets. Various proteomic tools and multiple combinations were developed in this area. Out of the proteomic technology armentarium, mass spectrometry and array technologies are the most used approaches. The main characteristics of the proteomic technology used in this domain are high throughput and detection of minute concentration in small samples. We present herein, using various proteomic technologies, the identification in cancer cell lines and in tumour tissue EMT-related proteins, proteins that are involved in the activation of different cellular pathways. Proteomics has brought besides standard EMT markers (e.g., cell-cell adhesion proteins and transcription factors) other future potential markers for improving diagnosis, monitoring evolution, and developing new therapy targets. Future will increase the proteomic role in clinical investigation and validation of EMT-related biomarkers.

Reactive Carbonyl Species as Potential Pro-Oxidant Factors Involved in Lichen Planus Pathogenesis

The constant generation of reactive carbonyl species (RCSs) by lipid peroxidation during aerobic metabolism denotes their involvement in cell homeostasis. Skin represents the largest organ of the body that is exposed to lipid peroxidation. Previous studies have suggested the involvement of oxidative stress in the development of lichen planus (LP), a chronic inflammatory skin condition with a complex pathogenesis. The aim of our study is to investigate a panel of pro-oxidants (4-hydroxy-nonenal (4-HNE), thiobarbituric acid reactive substances (TBARS), and malondialdehyde (MDA)), the total antioxidant status (TAS), and thiol-disulfide homeostasis parameters (TDHP), including total thiol (TT), native thiol (NT), disulfides (DS), DS/NT ratio, DS/TT ratio, and NT/TT ratio. The comparative determinations of serum levels of 4-HNE, TBARS, and MDA in patients with LP (n = 31) and controls (n = 26) show significant differences between the two groups (4-HNE: 7.81 ± 1.96 µg/mL vs. 6.15 ± 1.17 µg/mL, p < 0.05, TBARS: 4.23 ± 0.59 µmol/L vs. 1.99 ± 0.23 µmol/L, p < 0.05, MDA: 32.3 ± 6.26 ng/mL vs. 21.26 ± 2.36 ng/mL). The serum levels of TAS are lower in LP patients compared to the control group (269.83 ± 42.63 µmol/L vs. 316.46 ± 28.76 µmol/L, p < 0.05). The serum levels of TDHP are altered in LP patients compared to controls (NT: 388.10 ± 11.32 µmol/L vs. 406.85 ± 9.32., TT: 430.23 ± 9.93 µmol/L vs. 445.88 ± 9.01 µmol/L, DS: 21.06 ± 1.76 µmol/L vs. 19.52 ± 0.77µmol/L). Furthermore, a negative association between pro-oxidants and TAS is identified (4-HNE - rho = -0.83, p < 0.01, TBARS - rho = -0.63, p < 0.01, and MDA - rho = -0.69, p < 0.01). Understanding the mechanisms by which bioactive aldehydes exert their biological effects on the skin could help define effective therapeutical strategies to counteract the cytotoxic effects of these reactive metabolic intermediates.