Mediators of pruritus in psoriasis

Increased serum interleukin-31 levels correlate with pruritus in psoriatic patients: a cross-sectional study in Vietnam

Psoriasis is recognized not only as a skin disease but also as a systemic disorder. Interleukin-31 (IL-31) may be associated with psoriasis and systemic inflammation. We aimed to quantify serum IL-31 levels in patients with psoriasis and explore their associations with specific clinical manifestations. 30 patients with psoriasis and 30 healthy controls were included in this study. Demographic information and clinical characteristics were obtained through physical examination and medical history review. Serum IL-31 levels were measured using an enzyme-linked immunosorbent assay. IL-31 concentration was significantly higher in patients with psoriasis than in the control group (p<0.001). Patients with psoriasis vulgaris, psoriasis erythroderma, and pustular psoriasis had significantly higher serum IL-31 levels than healthy controls. Additionally, serum IL-31 levels were associated with itch numerical rating scale (NRS) scores and body mass index (BMI) but not with disease severity as measured by the Psoriasis Area and Severity Index (PASI). In patients with psoriasis, increased serum IL-31 levels correlated with itch severity but not with PASI. This suggests that IL-31 may play a critical role in the pathogenesis of psoriasis and could be a valuable target for further studies and therapeutic interventions.

Evaluation of Kynu, Defb2, Camp, and Penk Expression Levels as Psoriasis Marker in the Imiquimod-Induced Psoriasis Model

Background

Psoriasis is a noncontagious auto-inflammatory chronic skin disease. So far, some of the inflammatory genes were upregulated in mouse model of psoriasis. This study examined changes in skin mRNA expression of L-kynureninase (Kynu), cathelicidin antimicrobial peptide (Camp), beta-defensin 2 (Defb2), and proenkephalin (Penk) in a mouse model of imiquimod-induced psoriasis.

Materials and Methods

Tree groups of C57BL/6 female mice were allocated. The imiquimod (IMQ) cream was administered to the mice dorsal skin of the two groups to induce psoriatic inflammation. In the treatment group, IMQ was administered 10 min after hydrogel-containing M7 anti-IL-17A aptamer treatment. Vaseline (Vas) was administered to the negative control group. The psoriatic skin lesions were evaluated based on the psoriasis area severity index (PASI) score, histopathology, and mRNA expression levels of Kynu, Camp, Defb2, and Penk using real-time PCR. In order to assess the systemic response, the spleen and lymph node indexes were also evaluated.

Results

The PASI and epidermal thickness scores were 6.01 and 1.96, respectively, in the IMQ group, and they significantly decreased after aptamer administration to 1.15 and 0.90, respectively (P < 0.05). Spleen and lymph node indexes showed an increase in the IMQ group, followed by a slight decrease after aptamer treatment (P > 0.05). Additionally, the mRNA expression levels of Kynu, Defb2, Camp, and Penk genes in the IMQ-treated region showed a significant 2.70, 4.56, 3.29, and 2.61-fold increase relative to the Vas mice, respectively (P < 0.05). The aptamer-treated region exhibited a significant decrease in these gene expression levels (P < 0.05). A positive correlation was found between Kynu, Penk, and Camp expression levels and erythema, as well as Camp expression with PASI, scaling, and thickness (P < 0.05).

Conclusion

According to our results, it seems that Kynu, Camp, and Penk can be considered appropriate markers for the evaluation of psoriasis in IMQ-induced psoriasis. Also, the anti-IL-17 aptamer downregulated these important genes in this mouse model.

Cytokines in psoriasis: From pathogenesis to targeted therapy

Psoriasis is a multifactorial disease that affects 0.84% of the global population and it can be associated with disabling comorbidities. As patients present with thick scaly lesions, psoriasis was long believed to be a disorder of keratinocytes. Psoriasis is now understood to be the outcome of the interaction between immunological and environmental factors in individuals with genetic predisposition. While it was initially thought to be solely mediated by cytokines of type-1 immunity, namely interferon-γ, interleukin-2, and interleukin-12 because it responds very well to cyclosporine, a reversible IL-2 inhibitor; the discovery of Th-17 cells advanced the understanding of the disease and helped the development of biological therapy. This article aims to provide a comprehensive review of the role of cytokines in psoriasis, highlighting areas of controversy and identifying the connection between cytokine imbalance and disease manifestations. It also presents the approved targeted treatments for psoriasis and those currently under investigation.

Efficacy and safety of epidural block with lidocaine for refractory severe plaque psoriasis: An open-label pilot study in real world setting

Epidural block using lidocaine, a non-selective blocker of voltage-gated sodium channels (Nav), has demonstrated efficacy in the treatment of severe plaque psoriasis in a limited number of cases. This study aimed to evaluate the effectiveness and safety of epidural lidocaine block in adult patients with severe, treatment-resistant plaque psoriasis. This was an open-label pilot study. Patients with severe plaque-type psoriasis unresponsive to at least one systemic treatment were enrolled for a 1-week epidural lidocaine block and followed up for 48 weeks. Thirty-six patients participated, with 32 completing the study. At the 12-week mark, there was a remarkable 59% improvement in the mean Psoriasis Area Severity Index (PASI) score (P < 0.001). By week 48, 28 out of 32 patients (87%) achieved PASI 75, while 18 out of 32 (56%) reached PASI 90. Within 7 days, 20 out of 21 patients (95%) reported a reduction in itch, with a mean itch reduction of 82% at day 1 and 94% at day 7. Notably, no severe side effects were observed. Epidural lidocaine block proved to be an effective and safe long-term treatment option for individuals with refractory severe plaque psoriasis.

Circadian rhythm of cutaneous pruritus

One of the most common and significant symptoms for skin disorders is pruritus. Additionally, it serves as a significant catalyst for the exacerbation or reoccurrence of skin diseases. Pruritus seriously affects patients' physical and mental health, and even the quality of life. It brings a heavy burden to the patients, the families, even the whole society. The pathogenesis and regulation mechanisms for pruritus are complicated and have not yet been elucidated. Previous clinical studies have shown that itch worsens at night in scabies, chronic pruritus, atopic dermatitis, and psoriasis, suggesting that skin pruritus may change with circadian rhythm. Cortisol, melatonin, core temperature, cytokines, and prostaglandins are the main regulatory factors of the circadian rhythm of pruritus. Recent studies have shown that some CLOCK genes, such as BMAL1, CLOCK, PER, and CRY, play an important role in the regulation of the circadian rhythm of pruritus by regulating the Janus tyrosine kinase (JAK)-signal transducer and activator of transcription (STAT) and nuclear factor kappa-B (NF-κB) signaling pathways. However, the mechanisms for circadian clock genes in regulation of circadian rhythm of pruritus have not been fully elucidated. Further studies on the mechanism of circadian clock genes in the regulation of circadian rhythm of pruritus will lay a foundation for elucidating the regulatory mechanisms for pruritus, and also provide new ideas for the control of pruritus and the alleviation of skin diseases.

Pathomechanism of Pruritus in Psoriasis and Atopic Dermatitis: Novel Approaches, Similarities and Differences

Pruritus is defined as an unpleasant sensation that elicits a desire to scratch. Nearly a third of the world's population may suffer from pruritus during their lifetime. This symptom is widely observed in numerous inflammatory skin diseases-e.g., approximately 70-90% of patients with psoriasis and almost every patient with atopic dermatitis suffer from pruritus. Although the pathogenesis of atopic dermatitis and psoriasis is different, the complex intricacies between several biochemical mediators, enzymes, and pathways seem to play a crucial role in both conditions. Despite the high prevalence of pruritus in the general population, the pathogenesis of this symptom in various conditions remains elusive. This review aims to summarize current knowledge about the pathogenesis of pruritus in psoriasis and atopic dermatitis. Each molecule involved in the pruritic pathway would merit a separate chapter or even an entire book, however, in the current review we have concentrated on some reports which we found crucial in the understanding of pruritus. However, the pathomechanism of pruritus is an extremely complex and intricate process. Moreover, many of these signaling pathways are currently undergoing detailed analysis or are still unexplained. As a result, it is currently difficult to take an objective view of how far we have come in elucidating the pathogenesis of pruritus in the described diseases. Nevertheless, considerable progress has been made in recent years.

Itch and Janus Kinase Inhibitors

Itch is a common skin symptom, with complex aetiology and pathogenesis. It is mediated by 2 pathways, the histaminergic and non-histaminergic pathways. Chronic itch is understood to be processed by the latter and is difficult to treat with traditional pruritus therapies. The Janus kinase and signal transducer and activator of transcription pathway is a signalling mechanism that regulates gene expression through various cytokines. Janus kinase inhibitors, which have been tested and used for several autoimmune diseases, have also been shown to be effective for itch through clinical trials and case reports. Janus kinase inhibitors could be a good choice for pruritus in atopic dermatitis, psoriasis, and other diseases, such as prurigo nodularis and lichen planus, with rapid itch relief compared with conventional treatments. The most common adverse effects reported include nasopharyngitis, acne, and elevated blood creatine phosphokinase levels. Janus kinase inhibitors are currently prescribed with warnings about a potential increase in malignancies and cardiovascular diseases and usage in people of older ages. This review aims to provide knowledge about itch and the Janus kinase and signal transducer and activator of transcription pathway and to analyse the current evidence for itch relief by Janus kinase inhibitors.

Sleep Disorders and Psoriasis: An Update

Psoriasis alters patients’ quality of life. Among the disorders associated with psoriasis, sleep disorders are common, although they are not directly assessed by most quality-of-life scores. Thus, the specific evaluation of sleep disorders using dedicated scores is necessary, especially because such disorders alter patients;’ physical and psychological health. The relationship between psoriasis and sleep disorders has been shown in numerous studies, but has not yet been fully elucidated. The aim of this study was to update knowledge of sleep disorders in patients with psoriasis, through a review of the scientific literature since 1980. This work covers several topics of interest, such as sleep assessment methods, the prevalence of sleep disorders in patients with psoriasis, factors predictive of sleep disorders in patients with psoriasis, the impact of sleep disorders on comorbidities and quality of life, pathogenic mechanisms, obstructive sleep apnoea and restless leg syndromes, and the impact of biotherapy treatments on sleep disorders in patients with psoriasis.

Significance of interleukin-31 (IL-31) gene polymorphisms and IL-31 serum level in psoriasis in correlation with pruritus

Introduction

Interleukin-31 (IL-31) impact on the development and clinical presentation of psoriasis as well as pruritus has not been widely investigated so far.

Aim

To analyse IL-31 -1066G/A and -2057G/A promoter gene polymorphisms as well as serum IL-31 level and their correlation with severity of psoriasis and pruritus in the population of northern Poland.

Material and methods

The study included 300 psoriasis patients and 186 healthy volunteers. The polymorphisms were analysed using amplified refractory mutation system - polymerase chain reaction (ARMS-PCR) method. Serum levels of IL-31 were measured using the enzyme-linked immunosorbent assay (ELISA) test.

Results

The -1066 AA genotype of the IL-31 gene was statistically more frequent in patients and it increased the risk of psoriasis (OR = 1.80; p = 0.04). The GG genotype as well as G allele of the IL-31 -2057 gene polymorphism were rarely observed in psoriasis and were associated with a decreased risk of the disease (OR = 0.6, p = 0.007 and OR = 0.7, p = 0.01, respectively). Serum levels of IL-31 were significantly elevated in psoriasis patients (p < 0.000001), however, they did not correlate with the studied polymorphic variants of the IL-31 gene, severity of psoriasis, disease onset, presence of psoriatic arthritis and pruritus intensity.

Conclusions

Distinct IL-31 promoter gene polymorphisms may be involved in psoriasis development. It seems that serum concentration of IL-31 may not be a reliable marker of psoriatic pruritus.

Pruritus, Allergy and Autoimmunity: Paving the Way for an Integrated Understanding of Psychodermatological Diseases?

Pruritus is a key symptom in allergology and dermatology, contributing to the global and huge impact on quality of life related to skin disorders, both those which are not related to a primary dermatosis (illness) and those which are linked with primary skin lesions (disease). This is particularly evident within psychophysiological dermatoses, a group of psychodermatological diseases where there is a primary dermatosis, where psychological stress plays a role, and where pruritus may represent a major and shared symptom. The etiopathogenesis of pruritus in those disorders sheds light on the link among psychopathological features, psychological stress and the subtle interface between allergic and autoimmune mechanisms, where mast cells play a pivotal role. Allergy has long been recognised as an altered reactivity to exogenous antigens (allergens), defined as an immediate hypersensitivity mediated by immunoglobulin E (IgE). In turn, the immunological understanding of atopy is related to an immediate hypersensitivity reaction to environmental antigens involving T-helper 2 (Th2) responses and the IgE production. Mast cells are major cells in the early phase of allergy, releasing the mediators involved in the symptoms associated with the allergic disease, including pruritus, when the allergen cross-links with IgE, whose mechanisms can be observed in acute urticaria and atopy. Some allergic reactions may persist and allergy may eventually lead to autoimmunity, with the development of a T-helper 1 (Th1) and then IgE-independent inflammation. For instance, in chronic spontaneous urticaria, the mast cell activation may include autoimmune mechanisms, where autoantibodies against the extracellular α subunit of the high-affinity IgE receptor (FcεRIα) and to IgE are observed, with the involvement of Th1 lymphocytes and the production of interferon-γ (INF-γ). The role of autoimmunity is also suggested in the etiopathogenesis of other psychophysiological dermatoses, namely psoriasis, atopic dermatitis and alopecia areata. In the latter, for example, mast cells were reported to be linked with the loss of immune privilege and they are the key cells involved in the experience of pruritus, whose intensity was reported to precede and be correlated with the onset of the hair loss. Furthermore, considering that the role of hair and skin is wide, from psychosocial aspects (communication and social interaction) to vital functions (such as, temperature control), it is straightforward that they are central in our interactions and synchronization with others and the world; thereby, we may admit that the psychophysiological dermatoses could represent a loss of such synchronization. Furthermore, they are often linked with psychopathology which strongly connects with the concept of desynchronization, namely, sleep disorders and depressive symptoms, the clinical expression of a dysfunction in the interplay among mast cells, pineal gland and melatonin, thus the circadian rhythm, as well as their connection with the hypothalamic corticotrophin-releasing hormone (CRH), well-known for its key role in stress response. Moreover, increasing evidence has supported the existence of cutaneous equivalents for these mechanisms, connecting with those central pathways. Thereby, taking all these concepts into consideration, this review intends to look into the updated evidence on the shared biological mechanisms between allergy and autoimmunity, underlining pruritus as a core element, then revisiting the key role of mast cells and discussing the connection with melatonin and immune-inflammatory pathways in the physiopathology of psychophysiological dermatoses, thus paving the way for the understanding of their psychosomatic correlates and a comprehensive psychodermatological approach.

TaaI/Cdx-2 AA Variant of VDR Defines the Response to Phototherapy amongst Patients with Psoriasis

1,25-dihydroxyvitamin-D₃ plays a central role in the immune system via binding to the vitamin D receptor. VDR polymorphisms have been associated with multiple autoimmune disorders, including psoriasis. Until now, five VDR polymorphisms, FokI, ApaI, BsmI, TaqI and TaaI/Cdx2, have been studied in psoriasis, with contradicting results. Therefore, this study aimed to evaluate the association of VDR polymorphisms with susceptibility to psoriasis, effectiveness of NB-UVB phototherapy and concentration of proinflammatory cytokines and vitamin D amongst the Polish population. VDR polymorphisms were analyzed by PCR-RFLP or real-time PCR. We found that the frequency of the TaaI/Cdx-2 GG genotype was significantly higher in psoriasis patients and was associated with regulation of IL-17 and IL-23 concentration. Moreover, TaaI/Cdx-2 AA might have a significant effect on the response to phototherapy amongst patients with psoriasis. Our results suggest that VDR is a susceptibility factor for psoriasis development. Moreover, TaaI/Cdx-2 variants have a significant effect on the response to phototherapy amongst patients with psoriasis and regulation of inflammatory response via decrease of IL-17 and IL-23 level after UVB phototherapy in the Polish population. Results of our study provide some evidence in support of the hypothesis that the vitamin D signaling pathway may be of relevance for pathogenesis and treatment of psoriasis.

Itch reduction using immersive virtual reality-An experimental pilot study

In a previous proof-of-concept study we have demonstrated that visual exposure to specific colors results in pruritic or antipruritic effects. To determine the effect of "antipruritic" colors when using immersive virtual reality (VR) and to assess whether psychometric values correlate with the response to the color exposure. In this cross-sectional interventional single-center study, itch patients were exposed to their subjective "antipruritic color" (defined by the Manchester Color Wheel) in a virtual monochromatic room for 10 min using a head-mounted display. Itch intensity rating (0-10 numerical rating scale [NRS]) was repeated at 1-min intervals. Additionally, dermatology life quality index, itch-related quality of life and the Hospital Anxiety and Depression Scale questionnaires were completed. Twenty-two patients (mean age 51.9 ± 23 years, 13 females) participated in the study. Following color exposure for 10 min itch intensity was significantly reduced compared to baseline (exact Wilcoxon signed-rank test, mdn-NRS 4.5 vs 3.0; z = -3.025, p = 0.001), confirmed by the area under the curve (z = -3.118; p = 0.001). No significant correlation between itch reduction and questionnaire scores was found (Spearman's Rho for all questionnaires). Visual exposure to the "antipruritic color" using immersive VR resulted in a significant decrease in itch intensity. This aligns with previous findings on the influence of colors on itch perception. The response of the intervention appeared independent of psychometric values. Thus, color exposure using immersive VR is a promising, low-cost, rapidly-acting, easily-applicable, non-pharmacological experimental antipruritic method.

The Disruptiveness of Itchiness from Psoriasis: A Qualitative Study of the Impact of a Single Symptom on Quality of Life

BACKGROUND

Pruritus is the most common symptom of psoriasis, with a significant impact on patient quality of life. In spite of this, the severity, persistence, and overall impact of itchiness has only been rarely formally assessed during standard psoriasis clinic visits. Objectives: We sought to understand the far-reaching impacts of itchiness on the lives of those with psoriasis and their families.

METHODS

We conducted a qualitative study with five focus groups and 10 semi-structured interviews from August 2018 to January 2019. We enrolled 25 individuals with a diagnosis of at least moderate plaque psoriasis and 11 family members (primarily significant others). Views and experiences were analyzed thematically via content analysis.

RESULTS

Itchiness considerably impacts those with plaque psoriasis and their families. Our narrative analysis produced three main themes relating to itchiness: the triggers of itchiness, including climate, emotions, and behaviors; the physical consequences of itchiness, including disruption of emotional well-being, sleep disturbance, and daily activities; and the prevention and treatment strategies used to alleviate itchiness.

CONCLUSION

Itchiness impacts the quality of life in those with psoriasis and their family members. We strongly urge clinicians to inquire about and monitor the severity and impact of itchiness in psoriasis patients.

Pruritus in psoriasis and atopic dermatitis: current treatments and new perspectives

Psoriasis and atopic dermatitis (AD) are two common chronic inflammatory skin diseases. Although showing different etiology and clinical manifestations, patients with either disease suffer from low health-related quality of life due to pruritus (dermal itch). Recent studies have revealed that more than 85% of psoriasis patients suffer from pruritus, and it is also the dominating symptom of AD. However, as this is a non-life treating symptom, it was partly neglected for years. In this review, we focus on current findings as well as the impact and potential treatments of pruritus in these two skin diseases. We first distinguish the type of itch based on involved mediators and modulators. This clear delineation between the types of pruritus based on involved receptors and pathways allows for precise treatment. In addition, insights into recent clinical trials aimed to alleviate pruritus by targeting these receptors are presented. We also report about novel advances in combinatorial treatments, dedicated to the type of pruritus linked to a causal disease. Altogether, we suggest that only a focused treatment tailored to the primary disease and the underlying molecular signals will provide fast and sustained relief of pruritus associated with psoriasis or AD.

Role of neuroimmune circuits and pruritus in psoriasis

Psoriasis is a chronic inflammatory skin disease presenting with an array of clinical phenotypes, often associated with pruritus. Environmental and psychological stressors can exacerbate psoriasis symptoms and provoke flares. Recent studies suggest a dysfunctional hypothalamic-pituitary-adrenal (HPA) axis in some patients with psoriasis that can result in immune dysregulation. The immune system, in turn, can communicate with the nervous system to induce, maintain or aggravate psoriasis. In the skin, peripheral sensory as well as autonomic nerves control release of inflammatory mediators from dendritic cells, mast cells, T cells or keratinocytes, thereby modulating inflammatory responses and, in case of sensory nerves, pruritus. In response to the environment or stress, cytokines, chemokines, proteases, and neuropeptides fluctuate in psoriasis and influence immune responses as well as nerve activity. Furthermore, immune cells communicate with sensory nerves which control release of cytokines, such as IL-23, that are ultimately involved in psoriasis pathogenesis. Nerves also communicate with keratinocytes to induce epidermal proliferation. Notably, in contrast to recent years the debilitating problem of pruritus in psoriasis has been increasingly appreciated. Thus, investigating neuroimmune communication in psoriasis will not only expand our knowledge about the impact of sensory nerves in inflammation and pruritus and give new insights into the impact of environmental factors activating neuroimmune circuits or of stress in psoriasis, but may also lead to novel therapies. This review summarizes the relevant literature on the role of neuroimmune circuits, stress and how the central HPA axis and its peripheral equivalent in the skin, impact psoriasis.

Salp15, a Multifunctional Protein From Tick Saliva With Potential Pharmaceutical Effects

Ixodes ticks are the main vectors for a number of zoonotic diseases, including Lyme disease. Ticks secrete saliva directly into a mammalian host while feeding on the host's blood. This action serves to modulate host immunity and coagulation, thus allowing ticks to attach and feed upon their host. One of the most extensively studied components of tick saliva is Salp15. Research has shown that this protein binds specifically to CD4 molecules on the surface of T lymphocytes, interferes with TCR-mediated signaling transduction, inhibits CD4+ T cell activation and proliferation, and impedes the secretion of interleukin 2 (IL-2). Salp15 also binds specifically to dendritic cell dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) to up-regulate the expression of CD73 in regulatory T cells. Collectively, these findings render this salivary protein a potential candidate for a range of therapeutic applications. Here, we discuss our current understanding of Salp15 and the mechanisms that might be used to treat disease.

Characteristics of Pruritus according to Morphological Phenotype of Psoriasis and Association with Neuropeptides and Interleukin-31

Background

Pruritus is a common symptom in psoriasis. However, few studies have assessed the characteristics of pruritus according to morphological phenotypes of psoriasis.

Objective

To investigate the characteristics of pruritus according to morphological phenotypes of psoriasis and to assess the association with inflammatory mediators related to pruritus.

Methods

Psoriasis patients were divided into 2 groups according to clinical phenotype: eruptive inflammatory (EI) and chronic stable (CS). Clinical data of pruritus were assessed by an itch questionnaire. Serum neuropeptides and cytokines including substance P, histamine, vasoactive intestinal peptide, neuropeptide Y, calcitonin gene-related peptide and interleukin-31 (IL-31) were quantitatively measured.

Results

In total, 50 patients with psoriasis (30 male, 20 female; mean age, 45.7 years) were studied (EI, n=15 and CS, n=35). Pruritus was reported by 80% of EI and CS patients. There were no significant differences in prevalence of pruritus, pruritus intensity, severity of psoriasis, serum neuropeptides, or IL-31 between the 2 groups.

Conclusion

The morphological phenotype does not seem to be an important factor affecting the prevalence and characteristics of pruritus in psoriasis.

Efficacy and safety of 308-nm excimer lamp in the treatment of scalp psoriasis: a retrospective study

BACKGROUND

Scalp psoriasis is a major therapeutic challenge due to the hindrance caused by hair. Treatment with the 308-nm excimer lamp is purported to provide many benefits over conventional phototherapy. This retrospective study evaluates the efficacy, safety, and effective dosage of 308-nm excimer light in the treatment of scalp psoriasis.

METHODS

We retrospectively reviewed the medical records of patients with scalp psoriasis who received treatment with 308-nm excimer light. Clinical and epidemiological data as well as details regarding treatment were statistically analyzed to determine the treatment outcomes.

RESULTS

Twenty patients with scalp psoriasis were included in the study. Their mean age was 47.45 ± 17.93 years. Eleven patients responded to treatment at the end of 10 sessions. The median baseline Psoriatic Scalp Severity Index (PSSI) was 12 (range, 3-32). At the end of the protocol, the median PSSI was 4.5 (range, 0-24), indicating a statistically significant reduction (P < 0.001). Common adverse effects included erythema, irritation, and desquamation.

CONCLUSION

The 308-nm excimer light appears to be an effective and safe modality that requires short treatment time. The modality could be considered as an alternative or adjuvant treatment for scalp psoriasis.

Relationship between the Degrees of Itch and Serum Lipocalin-2 Levels in Patients with Psoriasis

Background

Lipocalin-2 (LCN2), a protein secreted mainly by activated neutrophils, has been associated with neurodegeneration, obesity, and inflammatory responses. Serum LCN2 concentration has been reported elevated in patients with psoriasis, but lower in patients with atopic dermatitis (AD). Spinal astrocyte-derived LCN2 was found to be involved in enhancement of itch in a mouse model of AD. However, the relationship between LCN2 and itch in patients with psoriasis has not been determined. Objective. This study examined the correlation between serum LCN2 levels and the degrees of itch in patients with psoriasis.

Methods

Serum LCN2 concentrations were measured by enzyme-linked immunosorbent assays (ELISA) in patients with psoriasis and AD and in healthy controls. The degree of itch was assessed using a visual analog scale (VAS), and disease severity was determined by measuring psoriasis area and severity index (PASI) and scoring atopic dermatitis (SCORAD). Correlations among serum LCN2 level, VAS, PASI, and SCORAD were analyzed statistically. We further examined the serum LCN levels in psoriasis patients before and after biological treatment.

Results

Serum LCN2 concentrations were significantly higher in patients with psoriasis and AD than those in healthy controls. In patients with psoriasis, serum LCN2 concentrations were significantly correlated with VAS, but not with PASI. In contrast, serum LCN2 concentrations did not correlate with VAS or SCORAD in patients with AD. Serum LCN2 levels in psoriasis patients significantly decreased after the biological treatment along with improvement of VAS.

Conclusion

Serum LCN2 concentration is associated with the degree of itch in patients with psoriasis, suggesting that serum LCN2 may be a useful clinical marker for itch in psoriasis.

Sleep disturbance in psoriasis: a case-controlled study

BACKGROUND

Sleep is essential for daytime functioning and health. Given the physical symptoms of psoriasis, a higher prevalence of sleep disorders can be expected. So far, the studies examining sleep disturbance in psoriasis have been of less-than-optimal methodological quality and with mixed results.

OBJECTIVES

To examine the prevalence of sleep disturbance in patients with plaque psoriasis compared with a control group, to evaluate associations with health-related quality of life (HRQoL) and examine possible disease-related predictors of disturbed sleep.

METHODS

We used a cross-sectional, case-controlled design. Participants included 179 consecutively recruited patients with plaque psoriasis and 105 controls. Measures included psoriasis severity (Psoriasis Area and Severity Index); HRQoL (Dermatology Life Quality Index); insomnia severity [Insomnia Severity Index (ISI)]; sleep quality [Pittsburgh Sleep Quality Index (PSQI)]; stress (Perceived Stress Scale); itch (Itch Severity Scale); and depressive symptoms (Beck Depression Inventory). Analyses included group comparisons and regression analyses to identify predictors of sleep disturbance.

RESULTS

A total of 25% of patients with psoriasis reported clinical insomnia (ISI > 15), compared with 10·5% of controls. In all, 53·6% of patients with psoriasis were poor sleepers (PSQI > 5), compared with 21·9% of controls. Itch was statistically significantly associated with all sleep-related outcomes.

CONCLUSIONS

A higher proportion of patients with psoriasis experience poor sleep than controls from the general population. Itch was the main predictor of impaired sleep. Improved control of psoriasis with decreased itch may improve sleep disturbance in psoriasis.

Density of mast cells and intensity of pruritus in psoriasis vulgaris: a cross sectional study

BACKGROUND

Psoriasis is a chronic and prevalent disease, and the associated pruritus is a common, difficult-to-control symptom. The mediators involved in psoriatic pruritus have not been fully established.

OBJECTIVE

To evaluate associations between the number of mast cells in psoriatic lesions and the intensity of pruritus.

METHODS

29 patients with plaque psoriasis were recruited. In all participants, Psoriasis Area and Severity Index and Body Surface Area were assessed. A questionnaire was administered to obtain clinical information and the Dermatology Life Quality Index. Pruritus was assessed using a visual analog scale and skin biopsies were performed for staining with Giemsa and Immunohistochemistry with C-Kit.

RESULTS

Pruritus was observed in 91.3% of our patients. Median VAS was 6 (p25-75: 2-8). The immunohistochemical method revealed a mean of 11.32 mast cells/field and Giemsa staining revealed a mean of 6.72 mast cells/field. There was no correlation between the intensity of pruritus and mast cell count, neither in Immunohistochemistry (p = 0.15; rho = -0.27) nor in Giemsa (p = 0.16; rho = -0.27). Pruritus did not impact on the Dermatology Life Quality Index (p = 0.51; rho = -0.13).

STUDY LIMITATIONS

The small sample size may be considered the main limitation of our study.

CONCLUSIONS

Although mast cells are mediators of pruritus in many cutaneous diseases, our findings support that psoriatic pruritus is a complex disorder with multifactorial, complex pathophysiology, involving pruritogenic mediators others than mast cells.

Improvement in itch and other psoriasis symptoms with brodalumab in phase 3 randomized controlled trials

BACKGROUND

Patients with psoriasis have lesional symptoms, including itch, which can reduce quality of life. The efficacy and safety of brodalumab, an interleukin-17 receptor A antagonist, in treating moderate-to-severe psoriasis have been reported in three randomized, controlled, phase 3 trials (AMAGINE-1/-2/-3).

OBJECTIVE

The effect of brodalumab on lesional symptoms was assessed using the psoriasis symptom inventory (PSI), a validated patient-reported instrument.

METHODS

Patients were randomized to receive brodalumab (140 or 210 mg every 2 weeks [Q2W]), placebo (AMAGINE-1/-2/-3), or ustekinumab (AMAGINE-2/-3) during a 12-week induction phase, followed by a maintenance phase through week 52. Patients electronically rated the severity of PSI items (itch, burning, stinging, pain, redness, scaling, cracking and flaking) during the previous 24 h on a scale of 0 (not at all severe) to 4 (very severe). At each visit, the PSI total score responder status was assessed, with responders defined as having an average weekly total inventory score ≤8 with no item score >1 at week 12.

RESULTS

Across AMAGINE-1/-2/-3, brodalumab was associated with improvements in PSI total scores and itch scores vs. placebo from week 2 through week 12 (P < 0.001 in both domains). In AMAGINE-2/-3, brodalumab 210 mg Q2W demonstrated faster onset of PSI total score and itch responses (week 2, 22.1% and 36.4%, respectively) vs. ustekinumab (week 2, 6.9% and 17.1%, respectively) and was associated with improved itch responses vs. ustekinumab after 52 weeks of constant treatment.

CONCLUSION

Brodalumab demonstrated rapid, robust improvements in symptoms assessed by the PSI, including itch, vs. placebo and ustekinumab.

Altered gut microbiome promotes proteinuria in mice induced by Adriamycin

Inflammation has recently been attributed to dysbiosis of the gut microbiome, which has been linked to proteinuria in chronic kidney disease. Since Adriamycin® (ADR) is widely used to induce proteinuria in mouse models, the aim of this study was to explore the potential effect of gut microbiome on this process. Both ADR resistant (C57BL/6) and susceptible (BALB/C) strains were part of the induced nephropathy with ADR injection. BALB/C mice significantly presented increased urinary albumin/creatinine ratio (UACR) with renal lesions in pathology, but C57BL/6 mice were absent from kidney damage. Species and genus level resolution analysis showed a shift in gut microbial profile between BALB/C and C57BL/6 mice. ADR further altered the stool microbiome in BALB/C mice, particularly with enrichment of Odoribacter and depletion of Turicibacter, Marvinbryantia and Rikenella. Moreover, the level of UACR in BALB/C mice was marked related to the abundance of Marvinbryantia, Odoribacter and Turicibacter in stool. Meanwhile, ADR remarkably increased the serum levels of interleukin (IL)-2 in BALB/C mice, but not in C57BL/6 mice. It is suggested that the favorably altered stools as shown in the microbiome might promote the inflammation and proteinuria in ADR-sensitive mice, which provides a new insight on the pathogenicity of chronic kidney disease.

Antihistamines in the treatment of pruritus in psoriasis

Aim

To evaluate the efficacy of antihistamines in reducing pruritus in psoriasis, 61 patients were randomized to be treated for 1 week with clemastine (n = 20), levocetirizine (n = 21) or placebo (n = 20).

Material and methods

All patients received the same routine antipsoriatic treatment. Itch intensity was assessed with VAS and the Itch Questionnaire, and hand movements during sleep were counted with an accelerometer.

Results

There was a statistically significant decrease in mean VAS scoring in clemastine and levocetirizine groups (p < 0.001), but not in the placebo group. Questionnaire scoring decreased significantly during the study in all study groups, with the greatest improvement noted in the clemastine group. The number of wrist movements during sleep did not differ significantly between groups.

Conclusions

Antihistamines of the first and second generations seem to be effective in reducing itch in patients with psoriasis, albeit the antipruritic effect is rather moderate. These observations need to be confirmed on larger patient groups.

The relationship between pruritus and clinical variables in patients with psoriasis

Background

Pruritus is the most commonly occurring subjective symptom of dermatological disease. Published data on both prevalence and intensity of pruritus in psoriasis is limited.

Objective

In this study we aimed to investigate the prevalence of pruritus and its relation with psoriasis area severity index, body mass index and presence of systemic disease in patients with psoriasis.

Methods

We analyzed data of psoriatic patients diagnosed in our psoriasis outpatient clinic between March 2013 and June 2014 collected retrospectively from PSR-TR registration system.

Results

In total, 880 patients were analyzed. Pruritus was more prominent in female patients. This difference was statistically significant. No significant associations were found between age of patients, clinical type of disease and pruritus. The itching was more common in patients with higher body mass index. Presence of pruritus was correlated significantly with severity of psoriasis. Five hundred and sixty of 880 patients had no systemic disease. The presence of pruritus was not related with presence of systemic disease. Existence of systemic disease with psoriasis has minimal effect on pruritus.

Study Limitations

We did not evaluate intensity of pruritus.

Conclusions

Pruritus is not mentioned within the classical symptoms of psoriasis. Pruritus in psoriasis is a very unpleasant symptom with great potential to impair patient's quality of life and may exacerbate psoriasis as a Koebner phenomenon.

Korean Red Ginseng extract and ginsenoside Rg3 have anti-pruritic effects on chloroquine-induced itch by inhibition of MrgprA3/TRPA1-mediated pathway

Background

It was previously found that Korean Red Ginseng water extract (KRGE) inhibits the histamine-induced itch signaling pathway in peripheral sensory neurons. Thus, in the present study, we investigated whether KRGE inhibited another distinctive itch pathway induced by chloroquine (CQ); a representative histamine-independent pathway mediated by MrgprA3 and TRPA1.

Methods

Intracellular calcium changes were measured by the calcium imaging technique in the HEK293T cells transfected with both MrgprA3 and TRPA1 ("MrgprA3/TRPA1"), and in primary culture of mouse dorsal root ganglia (DRGs). Mouse scratching behavior tests were performed to verify proposed antipruritic effects of KRGE and ginsenoside Rg3.

Results

CQ-induced Ca²⁺ influx was strongly inhibited by KRGE (10 μg/mL) in MrgprA3/TRPA1, and notably ginsenoside Rg3 dose-dependently suppressed CQ-induced Ca²⁺ influx in MrgprA3/TRPA1. Moreover, both KRGE (10 μg/mL) and Rg3 (100 μM) suppressed CQ-induced Ca²⁺ influx in primary culture of mouse DRGs, indicating that the inhibitory effect of KRGE was functional in peripheral sensory neurons. In vivo tests revealed that not only KRGE (100 mg) suppressed CQ-induced scratching in mice [bouts of scratching: 274.0 ± 51.47 (control) vs. 104.7 ± 17.39 (KRGE)], but also Rg3 (1.5 mg) oral administration significantly reduced CQ-induced scratching as well [bouts of scratching: 216.8 ± 33.73 (control) vs. 115.7 ± 20.94 (Rg3)].

Conclusion

The present study verified that KRGE and Rg3 have a strong antipruritic effect against CQ-induced itch. Thus, KRGE is as a promising antipruritic agent that blocks both histamine-dependent and -independent itch at peripheral sensory neuronal levels.

Treatment of plaque psoriasis with an ointment formulation of the Janus kinase inhibitor, tofacitinib: a Phase 2b randomized clinical trial

Background

Most psoriasis patients have mild to moderate disease, commonly treated topically. Current topical agents have limited efficacy and undesirable side effects associated with long-term use. Tofacitinib is a small molecule Janus kinase inhibitor investigated for the topical treatment of psoriasis.

Methods

This was a 12-week, randomized, double-blind, parallel-group, vehicle-controlled Phase 2b study of tofacitinib ointment (2 % and 1 %) applied once (QD) or twice (BID) daily in adults with mild to moderate plaque psoriasis. Primary endpoint: proportion of patients with Calculated Physician’s Global Assessment (PGA-C) clear or almost clear and ≥2 grade improvement from baseline at Weeks 8 and 12. Secondary endpoints: proportion of patients with PGA-C clear or almost clear; proportion achieving Psoriasis Area and Severity Index 75 (PASI75) response; percent change from baseline in PASI and body surface area; change from baseline in Itch Severity Item (ISI). Adverse events (AEs) were monitored and clinical laboratory parameters measured.

Results

Overall, 435 patients were randomized and 430 patients received treatment. The proportion of patients with PGA-C clear or almost clear and ≥2 grade improvement from baseline at Week 8 was 18.6 % for 2 % tofacitinib QD (80 % confidence interval [CI] for difference from vehicle: 3.8, 18.2 %) and 22.5 % for 2 % tofacitinib BID (80 % CI: 3.1, 18.5 %); this was significantly higher vs vehicle for both dosage regimens. No significant difference vs vehicle was seen at Week 12. Significantly more patients achieved PGA-C clear or almost clear with 2 % tofacitinib QD and BID and 1 % tofacitinib QD (not BID) at Week 8, and with 2 % tofacitinib BID at Week 12. Pruritus was significantly reduced vs vehicle with 2 % and 1 % tofacitinib BID (starting Day 2), and 2 % tofacitinib QD (starting Day 3). Overall, 44.2 % of patients experienced AEs, 8.1 % experienced application site AEs, and 2.3 % experienced serious AEs. The highest incidence of AEs (including application site AEs) was in the vehicle QD group.

Conclusions

In adults with mild to moderate plaque psoriasis, 2 % tofacitinib ointment QD and BID showed greater efficacy than vehicle at Week 8, but not Week 12, with an acceptable safety and local tolerability profile.

Trial registration

NCT01831466 registered March 28, 2013.

Electronic supplementary material

The online version of this article (doi:10.1186/s12895-016-0051-4) contains supplementary material, which is available to authorized users.

Psychopathological Variables and Sleep Quality in Psoriatic Patients

Psoriasis is an inflammatory disease frequently associated with psychiatric disturbances and sleep disorders. The aim of the study was to assess the prevalence of depression, interaction anxiety, audience anxiety, and sleep quality in psoriatic patients. One hundred and two psoriatic patients were enrolled and underwent the following questionnaires: Zung Self-Rating Depression Scale (SDS), Interaction Anxiousness Scale (IAS), Audience Anxiousness Scale (AAS), Pittsburgh Sleep Quality Index (PSQI). The severity of skin lesions was assessed by Psoriasis Area Severity Index (PASI). The presence of a link between clinical variables and with demographic data has been investigated. Psoriasis was linked to depression, interaction and audience anxiety, as well as to poor sleep quality; 37.5% of patients were depressed, 46.1% scored above 37 at the IAS, 47.1% scored above 33 at the AAS. Thirty-nine subjects (38.2%) presented a PSQI ≥ 5. An association between interaction anxiety and lower limbs psoriasis-related erythema as well as between PSQI and head psoriasis-related erythema was found, particularly among male patients. Hence, psoriatic patients should be assessed from a holistic point of view, in order to identify associated disorders that could benefit from targeted treatments.

Itching sensation in psoriatic patients and its relation to body mass index and IL-17 and IL-31 concentrations

INTRODUCTION

According to available data, pruritus is a common symptom of psoriasis, however its characteristics and pathogenesis are not clearly understood.

AIM

The main aim of this study was to assess itching sensation among patients suffering from psoriasis, including its incidence and severity. All factors triggering and worsening pruritic symptoms were also carefully analyzed. The authors assessed the relationship of itch with body mass index (BMI) and severity of disease. Moreover, serum levels of interleukin 17 (IL-17) and IL-31 were analyzed in relation to Psoriasis Activity and Severity Index, BMI and severity of pruritus.

MATERIAL AND METHODS

The study group consisted of 60 patients with plaque-type psoriasis. Analysis of impact of pruritus on the quality of life and worsening factors was based on the questionnaire. The severity of pruritus was assessed with the use of two independent scales. Serum IL-17 and IL-31 levels were measured in 30 patients suffering from psoriasis and in 10 healthy controls using immunoassay tests.

RESULTS

88.3% of analyzed patients complained of itch and the most common factor which exacerbated pruritus was stress (39.6%). Pruritus in psoriasis was independent of gender, illness duration and extent of skin lesions. The average intensity of pruritus was assessed as moderate and did not correlate significantly with BMI level, IL-17 and IL-31.

CONCLUSIONS

Since the pathogenesis of pruritus in psoriasis is not fully understood, further investigation in this area needs to be conducted. Pruritus may be considered as a characteristic feature of psoriasis and, besides the skin lesions, should be a target in dermatological treatment to improve patient's quality of life.

Itch control by Toll-like receptors

Toll-like receptors (TLRs) are cellular sensors designed to recognize molecular danger signals associated with exogenous or endogenous threats. Their activation leads to initiation of the host's immune responses in order to remove or contain the danger. However, one of the most effective methods of defense against invading pathogens and parasites is itch. The perception of itch elicits the rapid defensive action to scratch, which can remove the offending pathogen or parasite before infection can occur. Recent findings show that TLRs such as TLR3, TLR4, and TLR7 are expressed in a subset of pruriceptive/nociceptive neurons in the dorsal root and trigeminal ganglion providing a direct link between TLR activation and itch. Activation of neuronal TLRs can initiate itch sensation by coupling with ion channels. Furthermore, TLRs are expressed in skin cells and glial cells in the spinal cord to regulate inflammation and neuroinflammation in chronic itch. Thus, identification of the role of TLRs in neurons, skin cells, and glial cells may provide new targets for the treatment of chronic itch, a common clinical problem associated with skin diseases, systemic diseases, and metabolic disorders, for which current treatments are far from sufficient.

Clinical characteristics of pruritus in patients with scalp psoriasis and their relation with intraepidermal nerve fiber density

Background

The scalp is frequently affected in psoriasis patients, and pruritus can adversely affect the quality of life of affected patients. Few studies have assessed pruritus in scalp psoriasis.

Objective

To determine the correlation among the clinical characteristics of pruritus, psoriasis scalp severity index (PSSI), and intraepidermal nerve fiber (IENF) density in psoriatic scalp lesions.

Methods

Eighty patients (53 men, 27 women; mean age, 46.4 years; mean PSSI, 19.9) with scalp psoriasis were evaluated by using the PSSI and the Leuven itch scale. Biopsies were obtained from the lesional and nonlesional skin of 19 patients (10 men, 9 women; mean age, 37.8 years; mean PSSI, 25.8). Immunofluorescence staining of protein gene product 9.5 was performed to determine the IENF density.

Results

Sixty-four patients (80%) complained of pruritus associated with scalp psoriasis, which negatively affected their quality of life to varying degrees. A moderate positive relation between PSSI score and pruritus intensity was identified (r=0.225 and p=0.044). The IENF density in psoriatic lesions was significantly higher than that in the nonlesional scalp (6.2±1.2 vs. 4.2±1.6, p<0.001). However, the correlations between IENF density and PSSI score, and IENF density and pruritus intensity were insignificant.

Conclusion

These results indicate that pruritus prevalence is high in patients with scalp psoriasis, and pruritus considerably influences the patients' daily lives and quality of life. In addition, high IENF density in psoriatic scalp lesions may play a role in the development of pruritus in scalp psoriasis.

Effectiveness of conventional drug therapy of plaque psoriasis in the context of consensus guidelines: a prospective observational study in 150 patients

BACKGROUND

Evidence for superior outcome by adhering to therapy guidelines is imperative to their acceptance and adaptation for the optimal management of disease variants.

OBJECTIVE

Comparative study of prospective outcomes in simultaneous consideration of independent variables in groups of 150 patients of plaque psoriasis either treated adhering to or in digression of standard guidelines.

METHODS

The psoriasis area severity index (PASI) and the dermatology life quality index (DLQI), prior to and after three months of uninterrupted therapy were examined in treatment groups among 150 patients. Recovery rates of 75% or more in PASI were compared. Independent variables were also examined for their bearing on the outcome.

RESULTS

The vast majority was early onset disease phenotype. All three treatment regimens when administered in adherence to the guidelines yielded significantly superior rates of defined recovery both in PASI and DLQI. Compromise of the therapeutic outcome appeared in high stress profiles, obesity, female sex and alcohol, tobacco or smoking habit.

CONCLUSION

Conventional drug therapy of plaque psoriasis yields superior outcome by adhering to the consensus guidelines. Psychiatric address to stress must be integral and special considerations for phenotypic/syndromic variants is emphasized for effective therapy of psoriasis.

Emerging role of Toll-like receptors in the control of pain and itch

Toll-like receptors (TLRs) are germline-encoded pattern-recognition receptors that initiate innate immune responses by recognizing molecular structures shared by a wide range of pathogens, known as pathogen-associated molecular patterns (PAMPs). After tissue injury or cellular stress, TLRs also detect endogenous ligands known as danger-associated molecular patterns (DAMPs). TLRs are expressed in both non-neuronal and neuronal cell types in the central nervous system (CNS) and contribute to both infectious and non-infectious disorders in the CNS. Following tissue insult and nerve injury, TLRs (such as TLR2, TLR3, and TLR4) induce the activation of microglia and astrocytes and the production of the proinflammatory cytokines in the spinal cord, leading to the development and maintenance of inflammatory pain and neuropathic pain. In particular, primary sensory neurons, such as nociceptors, express TLRs (e.g., TLR4 and TLR7) to sense exogenous PAMPs and endogenous DAMPs released after tissue injury and cellular stress. These neuronal TLRs are new players in the processing of pain and itch by increasing the excitability of primary sensory neurons. Given the prevalence of chronic pain and itch and the suffering of affected people, insights into TLR signaling in the nervous system will open a new avenue for the management of clinical pain and itch.

Oxidative stress induces itch via activation of transient receptor potential subtype ankyrin 1 in mice

OBJECTIVE

To investigate the role of oxidative stress in itch-indicative scratching behavior in mice, and furthermore, to define the cellular and molecular mechanisms underlying oxidative stress-mediated itch.

METHODS

Scratching behavior was induced by intradermal injection of the oxidants hydrogen peroxide (H₂O₂) or tert-butylhydroperoxide (tBHP) into the nape of the neck in mice. The mice were observed for 30 min.

RESULTS

Intradermal H₂O₂ (0.03%-1%) or tBHP (1-30 μmol) elicited robust scratching behavior, displaying an inverted U-shaped dose-response curve. Naloxone, an opioid receptor antagonist, but not morphine, largely suppressed the oxidant-induced scratching. Chlorpheniramine, a histamine H1 receptor antagonist, blocked histamine- but not oxidant-induced scratching, indicating the involvement of a histamine-independent mechanism in oxidant-evoked itch. Further, resiniferatoxin treatment abolished oxidant-induced scratching, suggesting an essential role of C-fibers. Notably, blockade of transient receptor potential subtype ankyrin 1 (TRPA1) with the selective TRPA1 antagonist HC-030031, or genetic deletion of Trpa1 but not Trpv1 (subfamily V, member 1) resulted in a profound reduction in H₂O₂-evoked scratching. Finally, systemic administration of the antioxidant N-acetyl-L-cysteine or trolox (a water-soluble vitamin E analog) attenuated scratching induced by the oxidants.

CONCLUSION

Oxidative stress by different oxidants induces profound scratching behavior, which is largely histamine- and TRPV1-independent but TRPA1-dependent. Antioxidants and TRPA1 antagonists may be used to treat human itch conditions associated with oxidative stress.

Narrow band ultraviolet B irradiations cause alteration in interleukin-31 serum level in psoriatic patients

Scientific communications indicate the disturbed expression of neuropeptides in the skin and serum in psoriasis vulgaris (PsV) patients. Narrow-band ultraviolet radiation (NB-UVB) is one of the systemic therapies of PsV. The aim of the study was to evaluate the influence of NB-UVB therapy on substance P (SP), calcitonin gene-related peptide (CGRP), brain-derived neurotrophic factor (BDNF), corticotropin-releasing factor (CRF) and interleukin-31 (IL-31) serum concentrations in PsV patients. 59 psoriatic patients with mean PASI (psoriasis area and severity index) 14.3 were treated with NB-UVB (20 exposures). The control group consisted of 50 healthy subjects, whose age and sex matched. In all patients, serum concentration of BDNF, CRF, IL-31 substance P and CGRP was analyzed by ELISA before the treatment and in psoriatic group the analysis was also done after 10 and 20 irradiations. In patients there was found a significantly higher concentration of IL-31 (215.3 vs. 748.6 ng/ml; p < 0.0001), SP (25.7 vs. 67.2 pg/ml; p < 0.01), CGRP (31.4 vs. 44.15 pg/ml; p < 0.01) and a lower concentration of CRF (0.89 vs. 0.426 ng/ml; p < 0.0001) and BDNF (16.39 vs. 14.15 ng/ml; p = 0.1216) in comparison with the controls. 20 NB-UVB exposures caused a significant decrease in IL-31 level (748.6 vs. 631.7 ng/ml; p < 0.0001). The NB-UVB therapy had no major effect on neuropeptides serum levels regardless of a number of irradiations. On the basis of our study it can be suggested that IL-31 is involved in pathogenesis of psoriasis and the NB-UVB therapy causes alterations in its level.

Inhibitory effect of Lactobacillus plantarum K-1 on passive cutaneous anaphylaxis reaction and scratching behavior in mice

Lactobacillus plantarum K-1 (LP) inhibiting AP-1 (c-Jun) and NF-κB activations was isolated from kimchi, and its inhibitory activity against scratching behavior and passive cutaneous anaphylaxis reaction in mice was investigated. Heat-inactivated LP (heated at 60°C for 30 min) potently inhibited the expression of TNF-α and IL-4 as well as the activation of their transcription factors, NF-κB and c-jun, in phorbol 12'-myristate 13'-acetate-stimulated RBL-2H3 cells. LP (1 × 10(10) CFU per mouse) showed a potent inhibition against passive cutaneous anaphylaxis reaction induced by the IgE-antigen complex in mice, inhibiting it by 87.5%. LP (1 × 10(10) CFU/mouse) inhibited histamine-induced scratching behavior by 58.9% compared to the control group. LP significantly inhibited vascular permeability induced by histamine. The inhibitory activity of LP against vascular permeability was in proportion to its inhibition against scratching behavior. LP potently inhibited histamine-induced cytokine production: it (1 × 10(10) CFU per mouse) inhibited IL-4, IL-1β, and TNF-α expression by 88.9%, 88.6%, and 98.9%, respectively. LP also inhibited IgE level increased by histamine by 85.3%. It inhibited histamine-induced the activations of their transcription factors, NF-κB and c-Jun. Based on these findings, LP may improve allergic diseases, such as anaphylaxis, atopic dermatitis, rhinitis, and pruritus by inhibiting the expression of IgE-switching cytokine IL-4 and proinflammatory cytokines IL-1β and TNF-α via NF-κB and AP-1 signaling pathways.

Evaluation of epidermal nerve density and opioid receptor levels in psoriatic itch

BACKGROUND

Psoriasis is a complex, multifactorial inflammatory skin disease with genetic and environmental interactions. Patients with psoriasis exhibit erythematous plaques with itch, but the mechanisms of psoriatic itch are poorly understood.

OBJECTIVES

This study was performed to investigate epidermal nerve density and opioid receptor levels in psoriatic skin with or without itch.

METHODS

Twenty-four patients with psoriasis aged between 39 and 82 years were included in this study. The number of epidermal nerve fibres, the levels of semaphorin 3A (Sema3A) and the expression patterns of μ- and κ-opioid systems were examined immunohistologically in skin biopsies from psoriatic patients with or without itch and healthy volunteers as controls.

RESULTS

The number of epidermal nerve fibres tended to increase in approximately 40% of psoriatic patients with itch compared with healthy controls, while such intraepidermal nerves were not observed in other itchy patients. In comparison with healthy controls, Sema3A levels also tended to decrease in the epidermis of psoriatic patients with itch. However, no relationship was found between nerve density and Sema3A levels in the epidermis of psoriatic patients with itch. The levels of μ-opioid receptor and β-endorphin in the epidermis were the same in healthy controls and psoriatic patients with or without itch. The levels of κ-opioid receptor and dynorphin A were significantly decreased in the epidermis of psoriatic patients with itch compared with healthy controls.

CONCLUSIONS

Based on Sema3A levels in the epidermis, epidermal opioid systems, rather than hyperinnervation, may be involved in the pathogenesis of psoriatic itch.

Expression of tachykinins and their receptors in plaque psoriasis with pruritus

BACKGROUND Various mediators of pruritus have been suggested that might be responsible for the mechanism of pruritus in psoriasis.

OBJECTIVES

To study the expression levels of members of the tachykinin family, substance P and neurokinin (NK) A and their receptors, NK-1 and NK-2, in psoriasis and to correlate their expression with the intensity of pruritus. A possible correlation with chronic stress and depression was also evaluated.

METHODS

Biopsies were obtained from 28 patients with chronic plaque psoriasis; the majority had pruritus. The samples were taken from lesional and nonlesional areas on the back and also from 10 healthy controls, for immunohistochemistry staining, and from lesional skin for radioimmunoassay. Prior to biopsy, the clinical severity of the psoriasis of each patient was assessed by the Psoriasis Area and Severity Index (PASI) and the intensity of pruritus was measured by using a visual analogue scale (VAS). Levels of depression and stress were measured using Beck's Depression Inventory (BDI) and the salivary cortisol test, respectively.

RESULTS

Substance P-, NKA- and NK-2 receptor-immunoreactive nerves, and non-neuronal inflammatory cells positive for substance P and NKA and their respective receptors, NK-1 and NK-2, were numerous in psoriasis compared with healthy controls. The numbers of substance P-positive nerves and NK-2 receptor-positive cells in lesional skin were significantly correlated to pruritus intensity. The cortisol ratio was inversely correlated with the number of NK-1 receptor-immunoreactive inflammatory cells in lesional and nonlesional psoriasis skin. There was also a positive correlation between the BDI score and the number of substance P-positive cells in nonlesional skin and with NK-1 receptor-positive cells in lesional and nonlesional skin.

CONCLUSIONS

Tachykinins may play a role in psoriasis per se, in addition to pruritus in this disease. Targeting the combined NK-1 and NK-2 receptors might be a possible treatment.

GABA and GABA(A) receptor expression on immune cells in psoriasis: a pathophysiological role

Psoriasis is a chronic inflammatory disease in which pruritus is a common symptom. Pruritus may be associated with the gamma-aminobutyric acid (GABA) system. The distribution of GABA and its GABA(A) receptor (R) was studied in involved and non-involved psoriatic skin, as well as normal healthy control skin, using an immunohistochemistry technique. Pruritus was determined using a visual analog scale. Inflammatory cells immunoreactive for the GABA ligand and the GABA(A) R were increased (P < 0.01, respectively) in the involved skin. Cells stained for GABA ligand were mostly macrophages with some lymphocytes, while cells stained for GABA(A) R were macrophages, neutrophils or lymphocytes. There was a positive correlation when comparing GABA ligand (P = 0.05) and GABA(A) R (P < 0.05) expressing inflammatory cells, with pruritus. The GABA ligand and its GABA(A) R may play a role for the pathogenesis of psoriasis as well as for pruritus in this disease.