Mental stress in atopic dermatitis--neuronal plasticity and the cholinergic system are affected in atopic dermatitis and in response to acute experimental mental stress in a randomized controlled pilot study

Are behavioral interventions a better choice for atopic dermatitis patients? A meta-analysis of 6 randomized controlled trials

BACKGROUND

The treatment for atopic dermatitis (AD) has been the focus of clinical research, and behavioral intervention is considered an indispensable treatment method. To our knowledge, no relevant meta-analysis has evaluated the effects of behavioral interventions on atopic dermatitis.

OBJECTIVES

To evaluate the effects of behavioral interventions on atopic dermatitis.

METHODS

The authors searched PubMed, EMBASE, and Cochrane CENTRAL to retrieve relevant RCTs (up to Feb 2022). The search strategy involved a combination of related keywords. The Cochrane Q and I2 statistics were used to assess heterogeneity.

RESULTS

Six RCTs involving seven reports with 246 patients were included. The results suggested that behavioral interventions could relieve eczema severity (correlation coefficient [r = -0.39]; p < 0.001) and scratching severity significantly (r = -0.19; p = 0.017), while not affect itching intensity (r = -0.02; p = 0.840). A sensitivity analysis confirmed the robustness of the results.

STUDY LIMITATIONS

An important limitation of this study was the insufficient number of RCTs and the limited sample size. In addition, the study lacked a control group receiving a type of intervention other than the experimental protocol. Another limitation was the short duration of follow-up.

CONCLUSIONS

This study suggests that behavioral interventions could be effective in treating atopic dermatitis by reducing eczema and scratching severity. Additionally, habit-reversal behavioral therapy may be more effective for treating atopic dermatitis.

Stress Affects Mast Cell Proteases in Murine Skin in a Model of Atopic Dermatitis-like Allergic Inflammation

Stress exposure worsens allergic inflammatory diseases substantially. Mast cells (MCs) play a key role in peripheral immune responses to neuroendocrine stress mediators such as nerve growth factor (NGF) and substance P (SP). Mast cell proteases (MCPs) and cholinergic factors (Chrna7, SLURP1) were recently described to modulate MC stress response. We studied MCPs and Chrna7/SLURP1 and their interplay in a mouse model for noise induced stress (NiS) and atopic dermatitis-like allergic inflammation (AlD) and in cultured MC lacking Chrna7. We found that the cholinergic stress axis interacts with neuroendocrine stress mediators and stress-mediator cleaving enzymes in AlD. SP-cleaving mMCP4+ MC were upregulated in AlD and further upregulated by stress in NiS+AlD. Anti-NGF neutralizing antibody treatment blocked the stress-induced upregulation in vivo, and mMCP4+ MCs correlated with measures of AlD disease activity. Finally, high mMCP4 production in response to SP depended on Chrna7/SLURP1 in cultured MCs. In conclusion, mMCP4 and its upstream regulation by Chrna7/SLURP1 are interesting novel targets for the treatment of allergic inflammation and its aggravation by stress.

Immunosuppressive and immunomodulating therapy for atopic dermatitis in pregnancy: an appraisal of the literature

Atopic dermatitis (AD) is the most common dermatological diagnosis during pregnancy. Treatment of AD during pregnancy can be challenging, due to the unpredictable course and the fact that the therapy needs to be safe for both the mother and the fetus. Here we present an up-to-date appraisal of the literature on the treatment options available for AD in patients planning pregnancy, during pregnancy, and during breastfeeding. All patients with AD are recommended to supplement any medical treatment with daily applications of emollients. The first step in the medical treatment for AD during pregnancy are topical corticosteroids, and/or topical tacrolimus. If required, UV-light therapy can also be considered. Treatment with systemic therapy during pregnancy should always rely on a careful risk-benefit assessment and be based on shared-decision making between the treating physician and patient. The first-line systemic treatment option is cyclosporine A, whereas azathioprine may be considered in patients already receiving this treatment prior to pregnancy. Systemic glucocorticoids may also be used. Treatment with systemic JAK inhibitors is not recommended, whereas treatment with mycophenolate mofetil and methotrexate is contraindicated. Targeted therapy with dupilumab is not generally recommended, due to lack of experience in human pregnancies, yet some case-reports on their use are emerging. These recommendations are based on the authors appraisal of existing literature and the current recommendation from the European Task Force on Atopic Dermatitis. It is always the responsibility of the treating physician to stay updated on the newest guidelines and literature when treating patients with AD during pregnancy.

Role of stress in skin diseases: A neuroendocrine-immune interaction view

Psychological stress is a crucial factor in the development of many skin diseases, and the stigma caused by skin disorders may further increase the psychological burden, forming a vicious cycle of psychological stress leading to skin diseases. Therefore, understanding the relationship between stress and skin diseases is necessary. The skin, as the vital interface with the external environment, possesses its own complex immune system, and the neuroendocrine system plays a central role in the stress response of the body. Stress-induced alterations in the immune system can also disrupt the delicate balance of immune cells and inflammatory mediators in the skin, leading to immune dysregulation and increased susceptibility to various skin diseases. Stress can also affect the skin barrier function, impair wound healing, and promote the release of pro-inflammatory cytokines, thereby exacerbating existing skin diseases such as psoriasis, atopic dermatitis, acne, and urticaria. In the present review, we explored the intricate relationship between stress and skin diseases from a neuroendocrine-immune interaction perspective. We explored the occurrence and development of skin diseases in the context of stress, the stress models for skin diseases, the impact of stress on skin function and diseases, and relevant epidemiological studies and clinical trials. Understanding the relationship between stress and skin diseases from a neuroendocrine-immune interaction perspective provides a comprehensive framework for targeted interventions and new insights into the diagnosis and treatment of skin diseases.

Aromatic oil from lavender as an atopic dermatitis suppressant

In atopic dermatitis (AD), nerves are abnormally stretched near the surface of the skin, making it sensitive to itching. Expression of neurotrophic factor Artemin (ARTN) involved in such nerve stretching is induced by the xenobiotic response (XRE) to air pollutants and UV radiation products. Therefore, AD can be monitored by the XRE response. Previously, we established a human keratinocyte cell line stably expressing a NanoLuc reporter gene downstream of XRE. We found that 6-formylindolo[3,2-b]carbazole (FICZ), a tryptophan metabolite and known inducer of the XRE, increased reporter and Artemin mRNA expression, indicating that FICZ-treated cells could be a model for AD. Lavender essential oil has been used in folk medicine to treat AD, but the scientific basis for its use is unclear. In the present study, we investigated the efficacy of lavender essential oil and its major components, linalyl acetate and linalool, to suppress AD and sensitize skin using the established AD model cell line, and keratinocyte and dendritic cell activation assays. Our results indicated that lavender essential oil from L. angustifolia and linalyl acetate exerted a strong AD inhibitory effect and almost no skin sensitization. Our model is useful in that it can circumvent the practice of using animal studies to evaluate AD medicines.

Integrating Osteopathic Principles for Enhanced Dermatological Outcomes: A Literature Review

This paper explores the impact of osteopathic medicine's principles and philosophy on dermatology conditions, focusing specifically on atopic dermatitis (AD), bullous pemphigoid (BP), and acne scars. The aim is to investigate how integrating osteopathic principles into dermatology can improve patient outcomes by addressing visible and internal health factors. The review was conducted through a literature search utilizing PubMed and Journal Storage. By focusing on the interconnectedness of mind, body, and spirit, osteopathic medicine could contribute to the effective treatment of AD. Stress management techniques have been found to significantly aid in the treatment of AD, as stress levels and social stress have a significant impact on the exacerbation of AD symptoms. Micro-needling is a promising treatment for atrophic acne scars, reducing scar severity scores by up to 68.3%. Combining micro-needling with trichloroacetic acid or non-ablative fractional laser technology further enhances treatment efficacy. The development of BP has been linked to alterations in the epidermis. Granzyme B has been identified as a contributing factor in dermal-epidermal junction separation and autoantibody formation, leading to BP. However, the specific link between osteopathic manipulation and Granzyme B levels in BP is not yet firmly established. Although osteopathic manipulation may impact the immune system and inflammation, further investigation is required to determine its precise effects on granzyme B and BP. Nonetheless, integrating osteopathic principles and philosophy into dermatology can improve patient outcomes by addressing visible and internal health factors. The benefits of such integration include improved patient-provider relationships, innovative treatments, better stress management, and individualized care plans. Practitioners should be educated on the significance of complete skin examinations for all patients, and future research should focus on exploring the benefits of osteopathic manipulation for dermatologic conditions. Further investigations into new dermatological treatment methods rooted in osteopathic principles are encouraged. The foundation of dermatology and osteopathic medicine share the importance of physical touch for diagnosis and treatment. An osteopathic approach to dermatology considers the link between cutaneous diseases and systemic health. This approach aligns with the four fundamental osteopathic beliefs: the body functions as a whole unit; a person is an integration of body, mind, and spirit that cannot be separated. The body can regulate itself, heal itself, and maintain its health. The body's structure and function are interdependent and work together. Rational treatment is based upon an understanding of the basic principles of body unity, self-regulation, and the interrelationship of structure and function.

Neurotrophins: Neuroimmune Interactions in Human Atopic Diseases

Allergic diseases are accompanied by a variety of symptoms such as pruritus, coughing, sneezing, and watery eyes, which can result in severe physiological and even psychological impairments. The exact mechanisms of these conditions are not yet completely understood. However, recent studies demonstrated a high relevance of neurotrophins in allergic inflammation, as they induce cytokine release, mediate interaction between immune cells and neurons, and exhibit different expression levels in health and disease. In this review, we aim to give an overview of the current state of knowledge concerning the role of neurotrophins in atopic disorders such as atopic dermatitis, allergic asthma, and allergic rhinitis.

Probing the Skin–Brain Axis: New Vistas Using Mouse Models

Inflammatory diseases of the skin, including atopic dermatitis and psoriasis, have gained increasing attention with rising incidences in developed countries over the past decades. While bodily properties, such as immunological responses of the skin, have been described in some detail, interactions with the brain via different routes are less well studied. The suggested routes of the skin–brain axis comprise the immune system, HPA axis, and the peripheral and central nervous system, including microglia responses and structural changes. They provide starting points to investigate the molecular mechanisms of neuropsychiatric comorbidities in AD and psoriasis. To this end, mouse models exist for AD and psoriasis that could be tested for relevant behavioral entities. In this review, we provide an overview of the current mouse models and assays. By combining an extensive behavioral characterization and state-of-the-art genetic interventions with the investigation of underlying molecular pathways, insights into the mechanisms of the skin–brain axis in inflammatory cutaneous diseases are examined, which will spark further research in humans and drive the development of novel therapeutic strategies.

Narrative review on the management of moderate-severe atopic dermatitis in pediatric age of the Italian Society of Pediatric Allergology and Immunology (SIAIP), of the Italian Society of Pediatric Dermatology (SIDerP) and of the Italian Society of Pediatrics (SIP)

Currently, there are a few detailed guidelines on the overall management of children and adolescents with moderate-severe atopic dermatitis. AD ​​is a complex disease presenting with different clinical phenotypes, which require an individualized and multidisciplinary approach. Therefore, appropriate interaction between primary care pediatricians, pediatric allergists, and pediatric dermatologists is crucial to finding the best management strategy. In this manuscript, members of the Italian Society of Pediatric Allergology and Immunology (SIAIP), the Italian Society of Pediatric Dermatology (SIDerP), and the Italian Society of Pediatrics (SIP) with expertise in the management of moderate-severe atopic dermatitis have reviewed the latest scientific evidence in the field. This narrative review aims to define a pathway to appropriately managing children and adolescents with moderate-severe atopic dermatitis.

An Open Trial on the Feasibility and Efficacy of a Mindfulness-Based Intervention with Psychoeducational Elements on Atopic Eczema and Chronic Itch

(1) Background: Mindfulness-based interventions (MBI) are psychological group interventions conducted over several weeks. Their effects on reducing stress and improving physical and psychological health have been proven in various clinical populations. Growing evidence suggests that MBIs might be beneficial for dermatology patients. This article reports on a novel Mindfulness-based Training for chronic Skin Conditions (MBTSC) with psychoeducational elements that was developed with the goal of improving self-regulation including stress management and emotion regulation in patients and to help in coping with disease symptoms such as itch and scratching. The intervention was tested in a pilot efficacy trial in order to examine feasibility and to collect preliminary data on the effectiveness of the intervention on disease severity including itch perception and on psychological distress in an atopic dermatitis (AD) sample. (2) Methods: Following an uncontrolled pre-test-post-test design based on standardized self-report measures, nine adult AD patients were recruited from a dermatology clinic. Data were collected at baseline, post-treatment and 3 month follow-up. Patients completed questionnaires assessing disease severity, itch perception, stress, anxiety and depression, mindfulness and intervention acceptability. The 7 week intervention included seven weekly sessions and a daily home-practice requirement, supported by guided audio-meditations and reading material. (3) Results: Quantitative data showed improvements in disease severity, itch perception and stress levels with small to medium effect sizes. Psychological distress increased at post-treatment—significantly in the case of depression. Qualitative data highlighted the mixed effects of MBTSC on symptoms. Treatment acceptability was high and 100% of the participants completed the intervention; (4) Conclusions: These data indicate that MBTSC is feasible and that it might be a useful tool as adjunct therapy for AD. Further studies with larger samples and control groups are needed.

Flare management in atopic dermatitis: from definition to treatment

Atopic dermatitis (AD) is a skin immune-mediated inflammatory disease with a chronic-recurrent course. Acute exacerbations or flares are an integral part of the AD course and are generally defined as disease worsening, requiring escalation/intensification of treatment. Management of flares is crucial since their prevention is a key aim of long-term disease control. Nevertheless, difficulties related to this aspect are several, starting from the definition of flare itself, which is not always satisfactory or unambiguous, and needs clarification. Indeed, this hurdle may reduce clarity on treatment choice and generate difficulties when comparing data between studies. Deepening our knowledge on flares could be highly relevant to both clinicians and patients to provide adequate control of the disease through patient education and appropriate treatment. This review aims to summarize current knowledge on the management of AD flares from definition to treatment, highlighting aspects that are still unclear, and identifying any necessary unmet needs to better manage AD.

The skin microbiome and the gut-skin axis

The microbiome plays a significant role in human health, homeostasis, immune system, and disease pathogenesis. Disrupted communication between the microbiome and host has been extensively studied in gastrointestinal diseases. To a lesser extent, there is emerging research on the skin microbiome and its connection with the gut, referred to as the gut-skin axis and its effects on dermatologic conditions. A basic overview will be provided of the gut and skin microbiome with a focus on the impact of this connection on cutaneous diseases, such as psoriasis, atopic dermatitis, rosacea, acne vulgaris, photoaging, and cutaneous wounds. In addition, we shall discuss nutrition-based approaches mediated through the gut-skin axis and topical treatments that could serve as potential adjunctive management by manipulation of the microbiome. In particular, there is a growing body of research on oral probiotics, prebiotics, and dietary modifications that may help improve symptoms for a variety of dermatologic conditions in select demographic groups.

Atopic dermatitis in psychodermatology: a concise review for dermatologists

Atopic Dermatitis (AD) is a chronic disease of the skin with significant pruritus and phases of exacerbation and remission. The hallmarks of AD are changes in the epithelial barrier and chronic inflammation. This condition is associated with an increased risk of developing mental disorders such as depression, anxiety, and suicidal ideation. It has been proposed that psychological stress may impact on immunological factors with an up-regulation of mediating neuropeptides at the level of central nervous system and secondary involvement of endocrine glands, peripheral nervous system, and immune resident skin cells. This article provides a concise review for dermatologists on the psychodermatology of AD, in order to highlight the putative common pathways between the dermatologic and mental health issues in this illness.

New Pathways for the Skin's Stress Response: The Cholinergic Neuropeptide SLURP-1 Can Activate Mast Cells and Alter Cytokine Production in Mice

Background: The alpha7 nicotinic acetylcholine receptor (Chrna7) plays an essential anti-inflammatory role in immune homeostasis and was recently found on mast cells (MC). Psychosocial stress can trigger MC hyperactivation and increases pro-inflammatory cytokines in target tissues such as the skin. If the cholinergic system (CS) and Chrna7 ligands play a role in these cascades is largely unknown.

Objective: To elucidate the role of the CS in the response to psychosocial stress using a mouse-model for stress-triggered cutaneous inflammatory circuits.

Methods: Key CS markers (ACh, Ch, SLURP-1, SLURP-2, Lynx1, Chrm3, Chrna7, Chrna9, ChAT, VAChT, Oct3, AChE, and BChE) in skin and its MC (sMC), MC activation, immune parameters (TNFα, IL1β, IL10, TGFβ, HIF1α, and STAT3) and oxidative stress were analyzed in skin from 24 h noise-stressed mice and in cultured MC (cMC) from C57BL/6 or Chrna7-Knockout mice.

Results: First, Chrna7 and SLURP-1 mRNA were exclusively upregulated in stressed skin. Second, histomorphometry located Chrna7 and SLURP-1 in nerves and sMC and demonstrated upregulated contacts and increased Chrna7+ sMC in stressed skin, while 5 ng/mL SLURP-1 degranulated cMC. Third, IL1β+ sMC were high in stressed skin, and while SLURP-1 alone had no significant effect on cMC cytokines, it upregulated IL1β in cMC from Chrna7-KO and in IL1β-treated wildtype cMC. In addition, HIF1α+ sMC were high in stressed skin and Chrna7-agonist AR-R 17779 induced ROS in cMC while SLURP-1 upregulated TNFα and IL1β in cMC when HIF1α was blocked.

Conclusions: These data infer that the CS plays a role in the regulation of stress-sensitive inflammatory responses but may have a surprising pro-inflammatory effect in healthy skin, driving IL1β expression if SLURP-1 is involved.

To stress or not to stress: Brain-behavior-immune interaction may weaken or promote the immune response to SARS-CoV-2

The COVID-19 pandemic continues to strongly affect people with health disadvantages, creating a heavy burden on medical systems and societies worldwide. Research is growing rapidly and recently revealed that stress-related factors such as socio-economic status, may also play a pivotal role. However, stress research investigating the underlying psychoneuroimmune interactions is missing. Here we address the question whether stress-associated neuroendocrine-immune mechanisms can possibly contribute to an increase in SARS-CoV-2 infections and influence the course of COVID-19 disease. Additionally, we discuss that not all forms of stress (e.g. acute versus chronic) are detrimental and that some types of stress could attenuate infection-risk and -progression. The overall aim of this review is to motivate future research efforts to clarify whether psychosocial interventions have the potential to optimize neuroendocrine-immune responses against respiratory viral infections during and beyond the COVID-19 pandemic. The current state of research on different types of stress is summarized in a comprehensive narrative review to promote a psychoneuroimmune understanding of how stress and its mediators cortisol, (nor)adrenaline, neuropeptides and neurotrophins can shape the immune defense against viral diseases. Based on this understanding, we describe how people with high psychosocial stress can be identified, which behaviors and psychosocial interventions may contribute to optimal stress management, and how psychoneuroimmune knowledge can be used to improve adequate care for COVID-19 and other patients with viral infections.

[Can Stress Interact with SARS-CoV-2? A Narrative Review with a Focus on Stress-Reducing Interventions that may Improve Defence against COVID-19]

OBJECTIVE

The COVID-19 pandemic is on the rise and causes many concerns and fears in the population as well as among medical care givers. This raises the question as to how psychosocial stress associated with the pandemic can be managed, and also if certain forms of stress can contribute to an increase in infections and critical illnesses.

METHODS

Against the background of the current state of research on stress and the immune response, we provide a narrative review of studies addressing the question as to how stress can influence the immune defence against viral diseases.

RESULTS

Excessive stress can compromise the barrier function of the airways and alter neuroendocrine control of immune function, which can create a virus-permissive immune response.

DISCUSSION

Because certain forms of stress can play a role in the successful immune defence against viral respiratory disease, it is important to identify people with high psychosocial stress and to help them manage their stress. Conclusion Psychosocial measures that contribute to improved stress management may have a positive effect on the immune response against viral respiratory infections.

Mouse models of atopic dermatitis: a critical reappraisal

Mouse models for atopic dermatitis (AD) are an indispensable preclinical research tool for testing new candidate AD therapeutics and for interrogating AD pathobiology in vivo. In this Viewpoint, we delineate why, unfortunately, none of the currently available so-called "AD" mouse models satisfactorily reflect the clinical complexity of human AD, but imitate more "allergic" or "irriant" contact dermatitis conditions. This limits the predictive value of AD models for clinical outcomes of new tested candidate AD therapeutics and the instructiveness of mouse models for human AD pathophysiology research. Here, we propose to initiate a rational debate on the minimal criteria that a mouse model should meet in order to be considered relevant for human AD. We suggest that valid AD models should at least meet the following criteria: (a) an AD-like epidermal barrier defect with reduced filaggrin expression along with hyperproliferation, hyperplasia; (b) increased epidermal expression of thymic stromal lymphopoietin (TSLP), periostin and/or chemokines such as TARC (CCL17); (c) a characteristic dermal immune cell infiltrate with overexpression of some key cytokines such as IL-4, IL-13, IL-31 and IL-33; (d) distinctive "neurodermatitis" features (sensory skin hyperinnervation, defective beta-adrenergic signalling, neurogenic skin inflammation and triggering or aggravation of AD-like skin lesions by perceived stress); and (e) response of experimentally induced skin lesions to standard AD therapy. Finally, we delineate why humanized AD mouse models (human skin xenotransplants on SCID mice) offer a particularly promising preclinical research alternative to the currently available "AD" mouse models.

Skin and Psychosomatics - Psychodermatology today

Modern psychodermatology relies on the bio-psycho-social disease model in psychosomatics, according to which biological, psychological and social factors (on various levels, from molecules to the biosphere) play a major role in the disease pathogenesis through complex, non-linear interactions over the entire disease course. It is nowadays experimentally proven that "emotions get into the skin". Recent research shows close anatomical, physiological and functional connections between skin and nervous system, already known to be ontogenetically related. These connections are reflected in many skin diseases where psychological and somatic etiological factors are closely intertwined. A holistic approach by the physician should do justice to this interdependence; biological, psychological and social factors should be adequately taken into account when taking anamnesis, making a diagnosis and choosing a therapy. The "visibility" of the skin organ bestows dermatology a special position among the various other clinical subjects, and renders a holistic, psychosomatic approach to the patient that is particularly important. The life course belongs also to modern psychodermatological approaches. Based on the modern psychodermatology concept, other corresponding sub-areas such as psychogastroenterology, psychocardiology etc. have emerged. After the theoretical part of this article, some selected skin diseases are discussed in more detail from the psychosomatic point of view.

Baseline characteristics, disease severity and treatment history of patients with atopic dermatitis included in the German AD Registry TREATgermany

BACKGROUND

The Atopic Dermatitis (AD) TREATgermany registry was initiated by the German Society for Dermatology (DDG) in 2011 to evaluate the 'real-life' situation of health care for patients with AD.

OBJECTIVES

Interim data analysis on baseline characteristics as well as current and prescribed systemic treatments of the TREATgermany registry patients.

METHODS

Patients (≥18 years) with moderate-to-severe AD [objective (o)SCORAD > 20], or with current or previous anti-inflammatory systemic treatment for AD within 24 months, were included and are followed up over at least 24 months. To assess clinical signs, the eczema area severity index (EASI, 0-72), the oSCORAD (0-83) and the Investigator Global Assessment (IGA; 6-point scale) were used. The disease severity was globally scored by the patients [Patient Global Assessment (PGA); six-step Likert scale]. Disease symptoms were assessed by the patient-oriented eczema measure (POEM, 0-28) and numeric rating scales (NRS, 0-10). Health-related quality of life was measured using the dermatological life quality index (DLQI, 0-30).

RESULTS

A total of 612 patients were recruited across 32 sites between 06/2016 and 01/2019 (mean age: 42.6 ± 14.2 years; mean oSCORAD: 40.8 ± 16.3). The mean POEM score was 16.3 ± 7.5. Pruritus was rated highest among subjective symptoms (NRS: 5.4 ± 2.7). The mean DLQI value was 11.3 ± 7.5. The frequency of arterial hypertension was lower (20.8%) compared with the general population, whilst this was higher for depression (10%). More than 60% of the patients had received systemic glucocorticosteroids, and 36.8% had received cyclosporine A prior to inclusion. Dupilumab was the leading substance documented as either 'current' (12.1%) or 'prescribed' (31.4%) at baseline.

CONCLUSIONS

These 'real-life' data clearly demonstrate the substantial disease burden. Most of TREATgermany patients were already treated with or prescribed dupilumab at baseline. Moreover, current findings indicate the urgent need for further alternative agents in order to achieve a perceptible improvement of quality of life of patients with moderate-to-severe AD.

Stress-induced Interaction of Skin Immune Cells, Hormones, and Neurotransmitters

PURPOSE

Although scientific articles mention the impact of psychological stress on skin diseases, few review the latest research on factors involved in this correlation. The skin actively responds to psychological stress, with involvement of skin immune cells, hormones, neurotransmitters. Skin immune cells actively regulate tissue inflammation with their proinflammatory and anti-inflammatory effects. Stress-induced skin reactions primarily include cytokine secretion (e.g. interleukin-6, interleukin-1, interferon-γ) and activation of skins peripheral corticotropin-releasing hormone (CRH)-proopiomelanocortin (POMC)-adrenocorticotropic hormone (ACTH)-corticosteroids axis, which leads to acute/chronic secretion of corticosteroids in the skin.

METHODS

This narrative review presents the current knowledge and latest findings regarding the impact of psychological stress on skin diseases, including information concerning psychoneuroimmune factors in stress-induced skin responses. Recent articles published in English available through the PubMed database and other prominent literature are discussed.

FINDINGS

Stress mediators, including cortisol, ACTH, and CRH from hypothalamus-pituitary-adrenal axis activation, induce various skin immune responses. Skin cells themselves can secrete these hormones and participate in skin inflammation. Thus, the local skin CRH-POMC-ACTH-corticosteroids axis plays a prominent role in stress-induced responses. Also, keratinocytes and fibroblasts produce hypothalamic and pituitary signal peptides and express receptors for them (CRH with receptors and POMC degradation peptides with melanocortin receptors), which allows them to respond to CRH by activating the POMC gene, which is then followed by ACTH and subsequently corticosteroids excretion. In addition, keratinocytes can express receptors for neurotransmitters (e.g. adrenaline, noradrenaline, dopamine, histamine, acetylcholine), neurotrophins, and neuropeptides (e.g. substance P, nerve growth factor), which are important in linking psychoneuroimmunologic mechanisms.

IMPLICATIONS

Psychoneuroimmunology provides an understanding that the skin is target and source of stress mediators. This locally expressed complex stress-induced network has been confirmed as active in many skin diseases (e.g. vulgar psoriasis, atopic dermatitis, chronic urticaria, human papillomavirus infections/warts, hair loss, acne). Skin reactions to stress and its influence on skin diseases may have implications for disease severity and exacerbation frequency, given the effect of locally secreted corticosteroids and other mediators that affect skin integrity, inflammation, and healing potential. Studies have also shown that introducing psychiatric treatment (drugs or psychotherapeutic methods) can have positive effects on dermatologic diseases influenced by psychological stress exposure. We hope this review provides clinicians and scientists with more complete background for further research in this field of skin psychoneuroimmunology.

Biological Sex and IgE Sensitization Influence Severity of Depression and Cortisol Levels in Atopic Dermatitis

BACKGROUND

Depression is a common comorbid condition with atopic dermatitis (AD), particularly during the active disease cycle. Controversial results regarding the contribution of biological sex, immunoglobulin E (IgE) sensitization, and cortisol on AD severity and comorbid depression justify further investigation.

OBJECTIVE AND METHODS

To explore the influence of sex and IgE sensitization on biochemical and psychological parameters, and severity of AD, a case-control study of 105 volunteers (56 AD, 49 healthy controls (HC); 50 males, 55 females) was conducted over 10 weeks, starting at dermatological symptom onset. Disease severity, serum IgE, cortisol and testosterone levels, and depression scores were assessed at study baseline and after 10 weeks of conventional treatment.

RESULTS

Dermatological severity differed among AD males by IgE sensitization and was elevated in males with extrinsic atopic dermatitis (EAD). Hamilton Depression Rating Scale (HAMD) scores were elevated in all patients at study baseline and improved with symptom reduction to HC levels, except female EAD. Severity of depression and dermatitis were correlated in EAD males at baseline and at week 10. Serum cortisol was elevated in male EAD at baseline, in contrast to males with intrinsic atopic dermatitis (IAD) at week 10. In addition, cortisol levels were found negatively correlated with SCORAD and HAMD scores in EAD males at week 10.

CONCLUSION

Pathophysiological features of AD and depression are likely related to different inflammation-based effects and appear to be biological sex-dependent. Cortisol levels depend on biological sex and IgE sensitization in AD and increase in males with EAD at exacerbation and IAD males at resolution. Biological sex-related disease triggers, IgE sensitization, and cortisol levels are important for the understanding of the mechanisms underlying AD and comorbid depression.

The importance of the neuro-immuno-cutaneous system on human skin equivalent design

The skin is a highly complex organ, responsible for sensation, protection against the environment (pollutants, foreign proteins, infection) and thereby linked to the immune and sensory systems in the neuro-immuno-cutaneous (NIC) system. Cutaneous innervation is a key part of the peripheral nervous system; therefore, the skin should be considered a sensory organ and an important part of the central nervous system, an 'active interface' and the first connection of the body to the outside world. Peripheral nerves are a complex class of neurons within these systems, subsets of functions are conducted, including mechanoreception, nociception and thermoception. Epidermal and dermal cells produce signalling factors (such as cytokines or growth factors), neurites influence skin cells (such as via neuropeptides), and peripheral nerves have a role in both early and late stages of the inflammatory response. One way this is achieved, specifically in the cutaneous system, is through neuropeptide release and signalling, especially via substance P (SP), neuropeptide Y (NPY) and nerve growth factor (NGF). Cutaneous, neuronal and immune cells play a central role in many conditions, including psoriasis, atopic dermatitis, vitiligo, UV-induced immunosuppression, herpes and lymphomas. Therefore, it is critical to understand the connections and interplay between the peripheral nervous system and the skin and immune systems, the NIC system. Relevant in vitro tissue models based on human skin equivalents can be used to gain insight and to address impact across research and clinical needs.

Mast Cells and Sensory Nerves Contribute to Neurogenic Inflammation and Pruritus in Chronic Skin Inflammation

The intimate interaction between mast cells and sensory nerves can be illustrated by the wheal and surrounding flare in an urticarial reaction in human skin. This reaction is typically associated with an intense itch at the reaction site. Upon activation, cutaneous mast cells release powerful mediators, such as histamine, tryptase, cytokines, and growth factors that can directly stimulate corresponding receptors on itch-mediating sensory nerves. These include, e.g., H1- and H4-receptors, protease-activated receptor-2, IL-31 receptor, and the high-affinity receptor of nerve growth factor (TrkA). On the other hand, sensory nerves can release neuropeptides, including substance P and vasoactive intestinal peptide, that are able to stimulate mast cells to release mediators leading to potentiation of the reciprocal interaction, inflammation, and itch. Even though mast cells are well recognized for their role in allergic skin whealing and urticaria, increasing evidence supports the reciprocal function between mast cells and sensory nerves in neurogenic inflammation in chronic skin diseases, such as psoriasis and atopic dermatitis, which are often characterized by distressing itch, and exacerbated by psychological stress. Increased morphological contacts between mast cells and sensory nerves in the lesional skin in psoriasis and atopic dermatitis as well as experimental models in mice and rats support the essential role for mast cell-sensory nerve communication in consequent pruritus. Therefore, we summarize here the present literature pointing to a close association between mast cells and sensory nerves in pruritic skin diseases as well as review the essential supporting findings on pruritic models in mice and rats.

Itch Processing in the Skin

Itching can result from activity of specialized primary afferent neurons (“pruriceptors”) that have been shown to express certain molecular markers such as B-type natriuretic peptide and several members of the Mrgpr-family in rodents. On the other hand, neurons involved in pain processing (“nociceptors”) can also provoke itching when the activation site is restricted to an isolated tiny spot within the epidermis. Individuals classified as having sensitive skin report increased itching and pain sensations upon weak external stimuli that are not painful or itchy in the control group. Numerous possible factors could contribute to sensitive skin along the pathway of transduction of the external stimuli into peripheral neuronal signals, followed by neuronal processing, finally resulting in the perception: (a) reduced local protective factors leading to impaired skin barrier function, (b) increased production of excitatory skin mediators, (c) sensitized peripheral neurons, (d) facilitated spinal and central processing, and (e) reduced descending inhibition from the central nervous system. For all of those pathophysiological mechanisms there are clinical examples such as atopic dermatitis (a,b,c), neuropathic itching (c,e), and restless leg syndrome (d,e). However, none of these factors have been directly linked to the occurrence of sensitive skin. Moreover, individuals reporting sensitive skin are heterogeneous and a subpopulation with defined pathophysiology has not yet been identified. Given that the condition is reported in about 50% of women, and thereby includes many healthy individuals, it appears problematic to assign a definitive pathophysiological mechanism to it.

Gene-environment interactions in primary atopic disorders

Environmental factors modify disease presentation and severity in allergic disorders. Primary atopic disorders (PADs) are a heterogenous group of single gene disorders that lead to significant atopic and allergic disease manifestations. However, a number of these monogenic diseases have variable penetrance suggesting that gene-gene and/or gene-environment interactions could modulate the clinical phenotype. Environmental factors such as diet, the microbiome at the epithelial-environment interface, the presence and/or extent of infection, and psychologic stress can alter disease phenotypic expression of allergic diseases, and PADs provide discrete contexts in which to understand these influences. We outline how gene-environment interactions likely contribute to a variable penetrance and expressivity in PADs. Dietary modifications of both macronutrients and/or micronutrients alter T-cell metabolism and may influence effector T-cell function. The mucosal microbiome may affect local inflammation and may remotely influence regulatory elements, while psychologic stress can affect mast cell and other allergic effector cell function. Understanding gene-environment interactions in PADs can hopefully provide a foundation for interrogating gene-environment interactions to common allergic disorders, and also present opportunities for personalized interventions based on the altered pathways and environmental influences in affected individuals.

European task force on atopic dermatitis position paper: treatment of parental atopic dermatitis during preconception, pregnancy and lactation period

Atopic dermatitis (AD) is a common inflammatory skin disease that affects both children and adults, including a large number of adults of reproductive age. Several guidelines for the treatment of AD exist, yet specific recommendations for the treatment of pregnant or lactating women and for adults planning to have a child are often lacking. This position paper from the European Task force on Atopic Dermatitis (ETFAD) is based on up-to-date scientific literature on treating pregnant and lactating women as wells as adults with AD planning to have a child. It is based on the expert opinions of members of the ETFAD and on existing safety data on the proposed treatments, many of which are derived from patients with other inflammatory diseases or from transplantation medicine. For treating future parents, as well as pregnant and lactating women with AD, the use of topical treatments including moisturizers, topical corticosteroids, tacrolimus, antiseptics such as chlorhexidine, octenidine, potassium permanganate and sodium hypochlorite (bleach) is deemed to be safe. Ultraviolet (UV) therapy may also be used. Systemic treatment should be prescribed only after careful consideration. According to the opinion of the ETFAD, treatment should be restricted to systemic corticosteroids and cyclosporine A, and, in selected cases, azathioprine.

Lynx Prototoxins: Roles of Endogenous Mammalian Neurotoxin-Like Proteins in Modulating Nicotinic Acetylcholine Receptor Function to Influence Complex Biological Processes

The cholinergic system modulates many biological functions, due to the widespread distribution of cholinergic neuronal terminals, and the diffuse release of its neurotransmitter, acetylcholine. Several layers of regulation help to refine and control the scope of this excitatory neurotransmitter system. One such regulatory mechanism is imparted through endogenous toxin-like proteins, prototoxins, which largely control the function of nicotinic receptors of the cholinergic system. Prototoxins and neurotoxins share the distinct three finger toxin fold, highly effective as a receptor binding protein, and the former are expressed in the mammalian brain, immune system, epithelium, etc. Prototoxins and elapid snake neurotoxins appear to be related through gene duplication and divergence from a common ancestral gene. Protein modulators can provide a graded response of the cholinergic system, and within the brain, stabilize neural circuitry through direct interaction with nicotinic receptors. Understanding the roles of each prototoxin (e.g., lynx1, lynx2/lypd1, PSCA, SLURP1, SLURP2, Lypd6, lypd6b, lypdg6e, PATE-M, PATE-B, etc.), their binding specificity and unique expression profile, has the potential to uncover many fascinating cholinergic-dependent mechanisms in the brain. Each family member can provide a spatially restricted level of control over nAChR function based on its expression in the brain. Due to the difficulty in the pharmacological targeting of nicotinic receptors in the brain as a result of widespread expression patterns and similarities in receptor sequences, unique interfaces between prototoxin and nicotinic receptor could provide more specific targeting than nicotinic receptors alone. As such, this family is intriguing from a long-term therapeutic perspective.

Mast cell-neural interactions contribute to pain and itch

Mast cells are best recognized for their role in allergy and anaphylaxis, but increasing evidence supports their role in neurogenic inflammation leading to pain and itch. Mast cells act as a "power house" by releasing algogenic and pruritogenic mediators, which initiate a reciprocal communication with specific nociceptors on sensory nerve fibers. Consequently, nerve fibers release inflammatory and vasoactive neuropeptides, which in turn activate mast cells in a feedback mechanism, thus promoting a vicious cycle of mast cell and nociceptor activation leading to neurogenic inflammation and pain/pruritus. Mechanisms underlying mast cell differentiation, activation, and intercellular interactions with inflammatory, vascular, and neural systems are deeply influenced by their microenvironment, imparting enormous heterogeneity and complexity in understanding their contribution to pain and pruritus. Neurogenic inflammation is central to both pain and pruritus, but specific mediators released by mast cells to promote this process may vary depending upon their location, stimuli, underlying pathology, gender, and species. Therefore, in this review, we present the contribution of mast cells in pathological conditions, including distressing pruritus exacerbated by psychologic stress and experienced by the majority of patients with psoriasis and atopic dermatitis and in different pain syndromes due to mastocytosis, sickle cell disease, and cancer.

Consensus-based European guidelines for treatment of atopic eczema (atopic dermatitis) in adults and children: part II

This guideline was developed as a joint interdisciplinary European project, including physicians from all relevant disciplines as well as patients. It is a consensus-based guideline, taking available evidence from other guidelines, systematic reviews and published studies into account. This second part of the guideline covers antimicrobial therapy, systemic treatment, allergen-specific immunotherapy, complementary medicine, psychosomatic counselling and educational interventions, whereas the first part covers methods, patient perspective, general measures and avoidance strategies, basic emollient treatment and bathing, dietary intervention, topical anti-inflammatory therapy, phototherapy and antipruritic therapy. Management of AE must consider the individual clinical variability of the disease. Systemic immunosuppressive treatment with cyclosporine, methotrexate, azathioprine and mycophenolic acid is established option for severe refractory cases, and widely available. Biologicals targeting the T helper 2 pathway such as dupilumab may be a safe and effective, disease-modifying alternative when available. Oral drugs such as JAK inhibitors and histamine 4 receptor antagonists are in development. Microbial colonization and superinfection may cause disease exacerbation and can require additional antimicrobial treatment. Allergen-specific immunotherapy with aeroallergens may be considered in selected cases. Psychosomatic counselling is recommended especially in stress-induced exacerbations. Therapeutic patient education ('Eczema school') is recommended for children and adult patients. General measures, basic emollient treatment, bathing, dietary intervention, topical anti-inflammatory therapy, phototherapy and antipruritic therapy have been addressed in the first part of the guideline.

The role of environmental factors in allergy: A critical reappraisal

Allergies are usually referred to as type I hypersensitivity reactions against innocuous environmental antigens, characterized by a Th2/IgE-dominated inflammation. They can manifest themselves in various organs, such as skin, gastrointestinal and respiratory tract, and comprise diseases as diverse as allergic rhinitis and conjunctivitis, bronchial asthma, oral allergy syndrome, food allergy, urticaria and atopic eczema, but also anaphylactic shock. Within the last decades, there was a significant global increase in allergy prevalence, which has been mostly attributed to changes in environment and lifestyle. But which, among all factors discussed, are the most relevant, and what are the mechanisms by which these factors promote or prevent the development of allergic diseases? To answer this, it is necessary to go back to the two key questions that have occupied allergy researchers for the last decades: Firstly, what makes an allergen an allergen? Secondly, why are more and more individuals affected? Within the last decade, we have made considerable progress in answering these questions. This review gives an overview over scientific progress in the field, summarizes latest findings and points out future prospective and research needs.

Impact of acute stress on itch sensation and scratching behaviour in patients with atopic dermatitis and healthy controls

BACKGROUND

Patients with atopic dermatitis (AD) often report that stress aggravates their itch. However, no study has investigated if and how acute stress influences itch sensation and scratching behaviour in these patients.

OBJECTIVES

We evaluated the impact of acute stress on experimentally induced cowhage itch perception and scratching behaviour in 16 healthy subjects and 15 patients with AD.

METHODS

The Trier Social Stress Test (TSST) was used to induce acute stress. The itch sensation, provoked by applying cowhage to the forearms, and off-site scratching behaviour (not directed at the cowhage application site) were compared before and after performing the TSST or the control condition (watching a video of landscape scenes).

RESULTS

In patients with AD, stress induced by TSST caused a significant reduction of cowhage-evoked itch but significantly increased off-site scratching behaviour. Such changes in itch perception and scratching behaviour were not observed in healthy controls. In addition, a significant positive correlation was noted between stress induced by TSST and clinical severity of eczema.

CONCLUSIONS

We speculate that psychological stress increases spontaneous scratching in patients with AD, which may enhance the vicious cycle of itching and scratching, resulting in aggravation of the skin eczema. These results provide new insights on the mechanism of acute stress-related exacerbation of itch in patients with AD.

UCHL1/PGP 9.5 Dynamic in Neuro-Immune-Cutaneous Milieu: Focusing on Axonal Nerve Terminals and Epidermal Keratinocytes in Psoriatic Itch

Psoriasis is an immunogenetic skin disease manifesting as plaque lesions on the skin. Patients with psoriasis frequently suffer from itch, an unpleasant sensation causing a desire to scratch. Psoriatic itch is mainly transmitted by unmyelinated C-fibers; however, the exact molecular mechanism of psoriatic itch is still unexplained. Protein gene product 9.5 (PGP 9.5) is a panneurological marker commonly used for analysis of peripheral peptidergic and nonpeptidergic nerves and identification of cutaneous neuro-immune-endocrine cells. However, some studies suggested that nonneuronal cells, like keratinocytes, may also express PGP 9.5. This phenomenon might be linked with impaired axonal transport, keratinocyte injury, or dysfunctions of neuro-immune-cutaneous connections. The aim of this study was to analyze the expression of PGP 9.5 in psoriatic skin. We observed significantly altered density of PGP 9.5-positive axonal nerve terminals in pruritic lesional (p=0.04) and nonlesional psoriatic skin (p>0.001) compared with controls. In contrast, no significant differences were observed between psoriatic skin without itch and controls. Furthermore, PGP 9.5 expression by suprabasal keratinocytes (SBKs) was significantly increased in itchy skin lesions (p=0.007) compared to skin without itch, and a positive correlation was observed between PGP 9.5 expression and itch intensity (r=0.64; p=0.02). Our findings indicate changes in peripheral innervations and psoriatic keratinocytes, which may influence neuro-immune-cutaneous homeostasis and modulate itch transmission.

Psychosomatic factors of atopic dermatitis exacerbation

BACKGROUND

The aim of this study was to estimate whether the stress, lack of social support, and poor emotional relationships influence the recurrence of AD in adults.

METHODS

Case-control study comprised 66 outpatients with AD and 132 controls with different skin diseases believed to be slightly influenced by psychosomatic factors. Participants were treated at the Department of Dermatology - Military Medical Academy and City Department for Skin and Venereal Diseases from January to June 2014. Stressful life events were assessed using the Paykel's Interview for Recent Life Events. The attachment relationship and perceived social support were assessed with the Experiences in Close Relationships Scale and with the Multidimensional Scale of Perceived Social Support, respectively. Univariate and multivariate logistic regression analyses were applied.

RESULTS

AD patients had significantly higher anxiety scores when initiating a close emotional relationship and when avoiding an affective attachment (OR = 1.49; CI = 1.13-1.97; P = 0.005 and OR = 1.63; CI = 1.16-2.30; P = 0.005, respectively). Perceived social support from family and friends was significantly lower among cases compared to controls (OR = 0.93; CI = 0.88-0.98; P = 0.009 and UO = 0.94; CI = 0.89-0.99; P = 0.027, respectively).

CONCLUSIONS

AD patients had higher anxiety scores, and those with low social support tended to have more frequent disease recurrence. The number of stressful life events did not differ between studied groups.

Elevated oxytocin and noradrenaline indicate higher stress levels in allergic rhinitis patients: Implications for the skin prick diagnosis in a pilot study

BACKGROUND & AIMS

The effects of acute stress on allergic symptoms are little understood. The intention of this clinical study was to study the effects of acute stress and related mediators in allergic rhinitis (AR), taking the wheal and flare reaction in skin prick testing (SPT) as a readout.

METHODS

19 healthy and 21 AR patients were first subjected to SPTs with grass pollen-, birch pollen- and house dust mite allergen extracts, histamine and negative control. Subsequently, participants were exposed to a standardized Trier Social Stress Test (TSST), followed by SPT on the contralateral forearm. Stress responders were identified based on the salivary cortisol levels and State-subscale of State-Trait-Anxiety Inventory (STAI-S). Blood samples were collected before and after TSST and adrenaline, noradrenaline, serotonin, oxytocin, platelet activating factor and prostaglandin D2 were analyzed by enzyme immunoassay (EIA).

RESULTS

SPT results of 14/21 allergics and 11/19 healthy who responded with stress after TSST were evaluated. No significant differences regarding SPT to allergens or histamine before and after the stress test could be calculated at the group level. But, the wheal and flare sizes after TSST increased or decreased substantially in several individuals, and unmasked sensitization in one "healthy" person, which could not be correlated with any mediator tested. The most significant finding, however, was that, independent of TSST, the baseline levels of oxytocin and noradrenaline were significantly higher in allergics.

CONCLUSION

High baseline levels of noradrenaline points toward higher stress levels in allergic patients, which might be counterregulated by elevated oxytocin. Moreover, our data indicate that acute stress may have a significant influence on SPT fidelity in susceptible individuals.

Non-corticosteroid adherence and itch severity influence perception of itch in atopic dermatitis

Topical corticosteroid phobia is an important problem in the treatment of atopic dermatitis as it can affect the ability to control disease severity and itch by reducing treatment adherence. Topical corticosteroid phobia often ends up even non-corticosteroid adherence. As such, non-corticosteroid adherence, disease severity and itch are likely to be associated with each other, but their relationship has yet to be thoroughly investigated. Thus, the purpose of this study is to investigate it in atopic dermatitis. Using data from 1190 participants in an Internet survey, we identified 255 non-corticosteroid users and 225 with moderate to severe itch who were defined as non-corticosteroid adherents. Corticosteroid users with the same itch categories (n = 878) served as controls. We also examined how itch severity affects the perception of itch in atopic dermatitis. Unexpectedly, non-corticosteroid adherents were less sensitive to the conditions to elicit itch such as perspiring, commuting homeward, drinking alcohol and wearing woolen clothes compared with the control. We also found that patients with severer itch were more sensitive to itch during/after bathing, when lying in bed, commuting homeward, studying/working, drinking alcohol, undressing, getting up in the morning, after a meal, ingesting piquant foods and when they were unoccupied, angry, busy, nervous, sad or enjoying themselves. In conclusion, we found that non-corticosteroid adherence and itch severity influence perception of itch in atopic dermatitis and discuss possible mechanisms underlying these results. The information obtained in this study may be useful for communication with and education of atopic dermatitis patients and their treatment in outpatient clinics.

Cellular and molecular immunologic mechanisms in patients with atopic dermatitis

Atopic dermatitis (AD) is a complex skin disease frequently associated with other diseases of the atopic diathesis. Recent evidence supports the concept that AD can also recognize other comorbidities, such as chronic inflammatory bowel or cardiovascular diseases. These comorbidities might result from chronic cutaneous inflammation or from a common, yet-to-be-defined immunologic background leading to immune deviations. The activation of immune cells and their migration to the skin play an essential role in the pathogenesis of AD. In patients with AD, an underlying immune deviation might result in higher susceptibility of the skin to environmental factors. There is a high unmet medical need to define immunologic endotypes of AD because it has significant implications on upcoming stratification of the phenotype of AD and the resulting targeted therapies in the development of precision medicine. This review article emphasizes studies on environmental factors affecting AD development and novel biological agents used in the treatment of AD. Best evidence of the clinical efficacy of novel immunologic approaches using biological agents in patients with AD is available for the anti-IL-4 receptor α-chain antibody dupilumab, but a number of studies are currently ongoing with other specific antagonists to immune system players. These targeted molecules can be expressed on or drive the cellular players infiltrating the skin (eg, T lymphocytes, dendritic cells, or eosinophils). Such approaches can have immunomodulatory and thereby beneficial clinical effects on the overall skin condition, as well as on the underlying immune deviation that might play a role in comorbidities. An effect of these immunologic treatments on pruritus and the disturbed microbiome in patients with AD has other potential consequences for treatment.

Psychological and Educational Interventions for Atopic Dermatitis in Adults: A Systematic Review and Meta-Analysis

Psychological and educational interventions are valuable adjuncts in the management of adult atopic dermatitis. We performed a systematic review and meta-analysis of randomised controlled trials (RCTs) of the efficacy of these interventions. Twelve articles published between 1986 and 2013 were identified through electronic searches. The methodological quality was assessed according to the Cochrane Handbook for Systematic Reviews of Interventions, version 5.1.1 (Higgins & Green, 2015). A random-effects model was used to estimate the standardised mean difference (SMD). No significant difference was found in eczema severity determined in three RCTs (124 participants; SMD, -0.29; 95% CI [-0.64, 0.07]) and dropout rate in five RCTs (198 participants; relative risk, 0.66; 95% CI [0.20, 2.17]). Education via online video was significantly superior to handouts in ameliorating eczema severity in one RCT (80 participants). We conclude that, rather than a combination of these interventions with conventional therapy being of no value, the data did not have sufficient power to provide evidence-based conclusions.

Spinal activation of alpha7-nicotinic acetylcholine receptor attenuates posttraumatic stress disorder-related chronic pain via suppression of glial activation

The high prevalence of chronic pain in posttraumatic stress disorder (PTSD) individuals has been widely reported by clinical studies, which emphasized an urgent need to uncover the underlying mechanisms and identify potential therapeutic targets. Recent studies suggested that targeting activated glia and their pro-inflammatory products may provide a novel and effective therapy for the stress-related pain. In this study, we investigated whether activation of alpha-7 nicotinic acetylcholine receptor (α7 nAChR), a novel anti-inflammatory target, could attenuate PTSD-related chronic pain. The experiments were conducted in a rat model of single prolonged stress (SPS), an established model of PTSD-pain comorbidity. We found that SPS exposure produced persistent mechanical allodynia. Immunohistochemical and enzyme-linked immuno sorbent assay analysis showed that SPS also induced elevated activation of glia cells (including microglia and astrocytes) and accumulation of pro-inflammatory cytokines in spinal cord. In another experiment, we found that intrathecal injection of PHA-543613, a selective α7 nAchR agonist, attenuated the SPS-evoked allodynia in a dose dependent manner. However, this anti-hyperalgesic effect was blocked by pretreatment with methyllycaconitine (MLA), a selective α7 nAchR antagonist. Further analyses showed that PHA-543613 suppressed SPS-induced spinal glial activation and SPS-elevated spinal pro-inflammatory cytokines, and these were abolished by MLA. Taken together, the present study showed that spinal activation of α7 nAChR by PHA-543613 attenuated mechanical allodynia induced by PTSD-like stress, and the suppression of spinal glial activation may underlie this anti-hyperalgesic effect. Our study demonstrated the therapeutic potential of targeting α7 nAChR in the treatment of PTSD-related chronic pain.

Stressed skin?--a molecular psychosomatic update on stress-causes and effects in dermatologic diseases

A pathogenetically relevant link between stress, in terms of psychosocial stress, and disease was first described in the 1970s, when it was proven that viral diseases of mucous membranes (such as rhinovirus and Coxsackie virus infections) develop faster and more severe after stress exposure. Since then, there has been an annual increase in the number of publications which investigate this relationship and break it down to the molecular level. Nevertheless, the evidences for the impact of psychosocial stress on chronic inflammatory skin diseases and skin tumors are hardly known. In the present review, we outline current insights into epidemiology, psychoneuroimmunology, and molecular psychosomatics which demonstrate the manifold disease-relevant interactions between the endocrine, nervous, and immune systems. The focus is on stress-induced shifts in immune balance in exemplary disorders such as atopic dermatitis, psoriasis, and malignant melanoma. The objective of this article is to convey basic psychosomatic knowledge with respect to etiology, symptomatology, and therapeutic options for chronic skin diseases. Particular attention is directed towards the underlying molecular relationships, both from a somatic to mental as well as a mental to somatic perspective.

Stress-related skin disorders

Emerging research has suggested that the skin is not only a target of organismal distress but also an active participant of the stress response through production of local "HPA axis" components, peripheral nerve endings, and resident skin cells, including keratinocytes, mast cells, and immune/immune accessory cells. There are also bidirectional communication pathways between the brain and the skin, which play significant roles in integrating these interactions. In this review, we summarize the intricate relations between stress and several skin conditions. We have tried to identify the underlying mechanisms that link stress to the common dermatoses according to the latest scientific findings.

Association of Perceived Stress with Atopic Dermatitis in Adults: A Population-Based Study in Korea

Atopic dermatitis (AD) is a widely prevalent skin disease that affects both children and adults. The aim of the study was to assess the association of perceived stress (single-item, self-reported) with AD (self-reported) in a sample of Korean adults using a cross-sectional research design. A cross-sectional study was conducted using data from 33,018 adults aged 20 years and older collected in the 2007-2012 Korea National Health and Nutrition Examination Surveys (KNHANES). An increased level of self-reported stress was positively associated with an increased prevalence of AD in Korean adults (p for trend <0.001). After adjusting for covariates, the odds ratios (ORs) of AD among participants reporting high and very high levels of stress were 1.81 (95% confidence interval (CI): 1.22, 2.67) and 2.17 (95% CI: 1.38, 3.42), respectively, compared with those who reported low levels of stress. This study found a statistically significant association between perceived stress and AD among Korean adults.