Allergic skin diseases

Update on Urticaria and Angioedema

Urticaria and angioedema are caused by immunoglobulin E- and non-immunoglobulin E-mediated release of histamine and other inflammatory mediators from mast cells and basophils. Diagnosis is made clinically, and anaphylaxis must be ruled out if urticaria or angioedema is present. A limited nonspecific laboratory workup should be considered unless elements of the history or physical examination suggest specific underlying conditions. The mainstay of treatment is avoidance of triggers when and if triggers are identified. The first-line pharmacotherapy is second-generation H1 antihistamines, which can be titrated to greater than standard doses.

Impact of fucosyltransferase 1-mediated epidermal blood group antigen H on anti-inflammatory response in atopic dermatitis

The presence of the blood group H2 antigen on the membrane of red blood cells determines blood type O in individuals and this H2 antigen serves as a precursor to the A and B antigens expressed in blood types A and B, respectively. However, the specific involvement of ABH antigens in skin diseases is unknown. Therefore, we aim to investigate the expression of ABH antigens in skin tissue of patients with atopic dermatitis (AD) and MC903-induced AD-like mice. We demonstrated that the expression of ABH antigen is primarily located in the granular and horny layers of the skin in healthy control individuals. However, in patients with AD, the expression of the ABH antigen was absent or diminished in these layers, while the H2 antigen expression increased in the spinous layers of the affected skin lesions. Then, we investigated the biological function of blood group H antigen mediated by fucosyltransferase 1 (Fut1) in the skin, utilizing an AD mouse model induced by MC903 in wild-type (WT) and Fut1-knockout mice. After the application of MC903, Fut1-deficient mice, with no H2 antigen expression on their skin, exhibited more severe clinical signs, increased ear swelling, and elevated serum IgE levels compared with those of WT mice. Additionally, the MC903-induced thickening of both the epidermis and dermis was more pronounced in Fut1-deficient mice than that in WT mice. Furthermore, Fut1-deficient mice showed a significantly higher production of interleukin-4 (IL-4) and IL-6 in skin lesions compared with that of their WT counterparts. The expression of chemokines, particularly Ccl2 and Ccl8, was notably higher in Fut1-deficient mice compared with those of WT mice. The infiltration of CD4+ T cells, eosinophils, and mast cells into the lesional skin was significantly elevated in Fut1-deficient mice compared with that in WT mice. These findings demonstrate the protective role of H2 antigen expression against AD-like inflammation and highlight its potential therapeutic impact on AD through the regulation of blood group antigens.

Global Research Trend on Allergic Skin Disorders: A Bibliometric Analysis from 2001 to 2020

Background

Allergic skin disorders constitute a variety of inflammatory skin disorders with increasing incidence. Bibliometric studies involve a statistical analysis of academic literature to assess the current research trend and identify knowledge gaps. There is a dearth of such studies concerning allergic skin disorders.

Aim

To perform a bibliometric analysis of global research concerning allergic skin disorders from 2001 to 2020.

Materials and Methods

We obtained all data from the Web of Science using the keywords "atopic dermatitis," "contact dermatitis," "skin allergy," "urticaria," "food allergy," and "drug allergy." Only articles in English language were included. Subsequent analysis revealed the total number of publications, top journals, institutions, and countries, thus highlighting the overall research trend.

Results

Overall 76,764 articles were published on allergic skin disorders from 2001 to 2020 (original articles > review articles). The United States of America (USA) contributed maximum publications (26.1%) followed by Germany (9.6%), Japan (8.2%), and England (8.1%). The Allergy is the most preferred journal for publishing skin allergy research. Most research concentrated on atopic dermatitis, pathomechanisms of allergic disorders, and their primary prevention.

Conclusion

This study evaluates the current landscape of skin allergy research. There has been a consistent increase in the number of publications concerning allergic skin disorders over the years. However, majority of the research publications are from developed countries. Hence, skin allergy-related research publication should be increased for diverse and enriched literary evidences.

Prevalence of Asthma, Allergic Rhinitis, and Atopic Dermatitis and Their Association With Oral Health in Saudi Arabia

Background  The word "atopy" is frequently used to describe immunoglobulin E (IgE)-mediated diseases. The prevalence of atopic dermatitis, allergic rhinitis, and asthma is increasing and disconcerting in Saudi Arabia. This study aims to investigate the association between allergic rhinitis, atopic dermatitis, asthma, and oral health among adults in the Makkah region of Saudi Arabia. Methods A cross-sectional study of 726 adults using an electronic questionnaire was adopted. The study was carried out from January to December 2022. The questionnaire included demographic data, patients' diseases in response to inclusion and exclusion criteria, oral health status and symptoms, and dental health-related behaviors. Results Most participants were aged from 18 to <40 years (79.1%). More than half of the participants were females (53.6%); 39.7% of participants had poor oral health. Poor health was significantly higher among obese subjects as well as those with lower levels of physical activity, higher perceived levels of stress, those who received a sealant, and those who brushed their teeth for ≤ one time per day. The results showed that the individual symptoms of oral health did not associate significantly with being diagnosed with allergic rhinitis or asthma in the past 12 months. However, atopic dermatitis was independently associated with a chipped or broken tooth (OR = 1.52) and pain in the tongue or inside the cheeks (OR = 3.57). Conclusion Poor oral health was significantly associated with atopic dermatitis in Saudi adults. Some systemic diseases are considered chronic diseases, and they are multifactorial; thus, we cannot claim that periodontal pathogens are the definite cause of systemic infections. More studies are necessary to find a definitive association.

Urticaria and Angioedema

Urticaria and angioedema are caused by immunoglobulin E- and non-immunoglobulin E-mediated release of histamine and other inflammatory mediators from mast cells and basophils. Diagnosis is made clinically, and anaphylaxis must be ruled out if urticaria or angioedema is present. A limited nonspecific laboratory workup should be considered unless elements of the history or physical examination suggest specific underlying conditions. The mainstay of treatment is avoidance of triggers when and if triggers are identified. The first-line pharmacotherapy is second-generation H1 antihistamines, which can be titrated to greater than standard doses.

Examination of colorectal cancer cases with metal allergy

PURPOSE

To report our initiatives and treatment results for patients with colorectal cancer with metal allergy.

METHODS

A total of 27 patients (2.6%) with a history of metal contact dermatitis were identified among 1027 patients who underwent curative resection of colorectal cancer from 2014 to 2020. The results of the patch test, perioperative results, and postoperative colonoscopy findings were also investigated.

RESULTS

The patch test for metal allergens and staples was performed in 21 patients (77.8%), and 13 of them (61.9%) tested positive for at least one metal allergen. Ni (38.1%), Co (28.6%), and Pd (19.0%) showed higher positive rates than other metals, and 1 patient (4.8%) tested positive for staples. Stapled anastomosis/suturing was performed as planned in 15 of 27 patients. In 10 patients, the anastomosis method was changed from stapled to hand-sewn according to the no-patch test results (60%), positivity for multiple metals (20%), positivity for staples (10%), and surgeon's judgment (10%). No complications and abnormal colonoscopy findings were found to be associated with stapled anastomosis/suturing.

CONCLUSION

The patch test is useful for selecting an optimal anastomosis method for patients with suspected metal allergy.

Acupuncture for Uremic Pruritus: A Systematic Review and Meta-Analysis

Uremic pruritus (UP) is a chronic disease that can seriously affect the quality of life of dialysis patients. Acupuncture is a non-medication therapy that has been used to treat pruritus disorders. This systematic review aimed to evaluate the efficacy and safety of acupuncture for the treatment of UP. A total of nine Chinese and English databases were searched from their inception to December 31, 2021, and 214 studies were retrieved. Finally, seven randomized controlled trials (n=504) were included in the meta-analysis performed using RevMan V.5.3. Results included effective rate, recurrence rates, and adverse events. Compared with conventional treatment, acupuncture was more effective in treating UP (risk ratio [RR]=1.28, 95% confidence interval [CI]=1.09 to 1.50, P=0.003). The results were consistent after sensitivity analysis (RR=1.38, 95% CI=1.21 to 1.57, P<0.00001). In subgroup analysis, the efficacy rates of acupuncture and medications (oral and topical) were comparable (RR=1.20, 95% CI=0.98 to 1.47, P=0.07). Acupuncture combined with hemodialysis was more effective than hemodialysis alone in relieving pruritus (RR=1.42, 95% CI=1.18 to 1.72, P=0.0002). Adverse events were reported in only three studies, including one case of hyperphosphatemia in the medications group (RR=0.29, 95% CI=0.01 to 7.06, P=0.45). None of the studies reported recurrence rates. In conclusion, acupuncture is a safe treatment modality for patients with UP receiving hemodialysis that can effectively improve UP symptoms, and acupuncture in combination with hemodialysis has more efficacy than hemodialysis alone in improving the UP symptoms.

Terminalia chebula Retz. extract ameliorates the symptoms of atopic dermatitis by regulating anti-inflammatory factors in vivo and suppressing STAT1/3 and NF-ĸB signaling in vitro

BACKGROUND

Terminalia chebula (TC) is a traditional medicinal plant used for treating various diseases in humans. However, pharmacological mechanisms underlying the effects of TC in atopic treatment remain unelucidated.

HYPOTHESIS/PURPOSE

We investigated the therapeutic effects of TC extract in a mouse model of atopic dermatitis (AD) in vivo and the anti-inflammatory mechanism in vitro.

STUDY DESIGN/METHODS

For the in vivo study, AD was induced by Dermatophagoides farinae extract (Dfe) in NC/Nga mice. After 14 days of oral administration, the effects of TC concentrations of 30, 100, and 300 mg/kg were analyzed by assessing morphological changes visually; measuring serum levels of inflammatory chemokines/cytokines, IgE, histamine, MDC, TARC, RANTES, and TSLP using ELISA kits; and counting infiltrated mast cells. For in vitro analyses, we used IFNγ/TNF-α-stimulated human keratinocyte cell lines to study the mechanism of action. The production of chemokines/cytokines in the IFNγ/TNF-α-stimulated HaCaT cells was measured using ELISA and a bead array kit. The signaling pathways were analyzed by western blotting and the expression of the transcriptional factors using RT-PCR and luciferase assay.

RESULTS

Administration of TC significantly alleviated AD-like symptoms in vivo and decreased the ear thickness, dermatitis score, keratinization, and mast cell infiltration. It also resulted in decreased serum levels of IgE, histamine, and inflammation-related mediators MDC, TARC, RANTES, and TSLP compared with those in the Dfe treatment group. Moreover, TC downregulated the expression of the inflammatory chemokines RANTES and MDC in IFNγ/TNF-α-stimulated HaCaT cells. TC inhibited phosphorylated STAT1/3 and NK-κB subunits and nuclear translocation of NF-κB. It also suppressed the transcription of IFNγ, IL-6, IL-8 and MCP-1 in the IFNγ/TNF-α-stimulated HaCaT cells. TC and its constituents, chebulic acid, gallic acid, corlagin, chebulanin, chbulagic acid, ellagic acid, and chebulinic acid, strongly inhibited the nuclear translocation of NF-κB, STAT1, and STAT3 and decreased the expression of inflammatory cytokines at the mRNA level.

CONCLUSIONS

Overall, TC extract alleviated AD-like symptoms by regulating anti-inflammatory factors in vivo and suppressing STAT1/3 and NF-κB signaling in vitro. In addition, our results show the in vivo effect of partial improvements in AD, as well as the in vitro effect on inflammatory factors by the constituents of TC. This finding provides that TC extract and its components could be potential therapeutic drugs for AD.

Facial Irritant Contact Dermatitis Caused by Pyraclostrobin

Contact dermatitis and facial contact dermatitis caused by pesticides are not uncommon in China. However, clinically, due to the wide variety of pesticides, they mainly appear in the form of case reports. We reported a 70-year-old male patient developed facial irritant contact dermatitis (ICD) due to pyraclostrobin which was sprayed on his face. Initially, he felt facial burning and tingling, and localized erythematous-edematous and scaly rash appeared on his face as well as front hairline scalp. During the outpatient visit, the main symptoms were a facial burning sensation, itching, and tingling. The patient’s facial lesions improved after treatment. To better protect the skin of agricultural workers, preventive measures should be undertaken, such as personal protective equipment, gas masks, protective clothing and goggles, which are indispensable for manual pesticide spraying. Pyraclostrobin diluted according to the instructions is a potential source of ICD. Agricultural workers should undertake preventive measures during manual pesticide spraying. Safety education and publicity are particularly important. We need dermatologists to spread knowledge and agricultural workers to develop the right protective habits.

Artemisia annua water extract attenuates DNCB-induced atopic dermatitis by restraining Th2 cell mediated inflammatory responses in BALB/c mice

ETHNOPHARMACOLOGICAL RELEVANCE

Artemisia annua L. (A. annua) is a traditional Chinese medicine that has been used since ancient times to treat malaria, eczema, dermatomycosis, jaundice, and boils. Modern pharmacological studies show that it has immunosuppressive and anti-inflammatory effects. However, the mechanism of A. annua in the treatment of atopic dermatitis (AD) remains unclear.

AIM OF THE STUDY

This study was aimed to investigate the effect of A. annua water extract (AWE) on 2,4-dinitrochlorobenzene (DNCB)-induced AD mouse model and tried to explore its possible underlying mechanisms.

MATERIALS AND METHODS

AD was induced in BALB/c mice by the topical repeated application of DNCB. Oral drug intervention of AWE and dexamethasone (DEX, positive control) began from the 7th day and continued for 13 consecutive days. The clinical skin score, ear thickness and the weight of ear and spleen were assessed. The ear tissue were stained with toluidine blue and hematoxylin and eosin (H&E) to detect inflammatory cell infiltration. IgE, terleukin (IL)-4 and IL-13 levels in the serum and IgE level in splenocytes were quantified by enzyme-linked immunosorbent assay (ELISA). The mRNA expression levels of IL-4, IL-6, IL-13, IL-17, tumor necrosis factor (TNF)-α and thymic stromal lymphopoietin (TSLP) were measured by quantitative real time polymerase chain reaction. The phosphorylation levels of mitogen-activated protein kinases (MAPKs)-p38 and nuclear factor (NF)-κB in ear tissue were detected by Western blot.

RESULTS

Results demonstrated that AWE treatment significantly attenuated the AD-like symptoms in DNCB-induced BALB/c mice, including the skin dermatitis severity and ear edema. Further study disclosed that AWE treatment suppressed the expressions of IgE, IL-4, IL-6, IL-13, IL-17, TNF-α and TSLP at mRNA and protein levels. Moreover, AWE showed inhibitory effect on the phosphorylation of p38 MAPK and NFκB in ear tissues of AD mice.

CONCLUSIONS

Collectively, our results suggested that AWE suppressed DNCB-induced AD in mice probably by restraining Th2 type inflammatory response. These findings might pave the road for the potential clinical application of AWE for AD treatment.

Exploring neuronal mechanisms involved in the scratching behavior of a mouse model of allergic contact dermatitis by transcriptomics

Background

Allergic contact dermatitis (ACD) is a common skin condition characterized by contact hypersensitivity to allergens, accompanied with skin inflammation and a mixed itch and pain sensation. The itch and pain dramatically affects patients’ quality of life. However, still little is known about the mechanisms triggering pain and itch sensations in ACD.

Methods

We established a mouse model of ACD by sensitization and repetitive challenge with the hapten oxazolone. Skin pathological analysis, transcriptome RNA sequencing (RNA-seq), qPCR, Ca²⁺ imaging, immunostaining, and behavioral assay were used for identifying gene expression changes in dorsal root ganglion innervating the inflamed skin of ACD model mice and for further functional validations.

Results

The model mice developed typical ACD symptoms, including skin dryness, erythema, excoriation, edema, epidermal hyperplasia, inflammatory cell infiltration, and scratching behavior, accompanied with development of eczematous lesions. Transcriptome RNA-seq revealed a number of differentially expressed genes (DEGs), including 1436-DEG mRNAs and 374-DEG-long noncoding RNAs (lncRNAs). We identified a number of DEGs specifically related to sensory neuron signal transduction, pain, itch, and neuroinflammation. Comparison of our dataset with another published dataset of atopic dermatitis mouse model identified a core set of genes in peripheral sensory neurons that are exclusively affected by local skin inflammation. We further found that the expression of the pain and itch receptor MrgprD was functionally upregulated in dorsal root ganglia (DRG) neurons innervating the inflamed skin of ACD model mice. MrgprD activation induced by its agonist β-alanine resulted in exaggerated scratching responses in ACD model mice compared with naïve mice.

Conclusions

We identified the molecular changes and cellular pathways in peripheral sensory ganglia during ACD that might participate in neurogenic inflammation, pain, and itch. We further revealed that the pain and itch receptor MrgprD is functionally upregulated in DRG neurons, which might contribute to peripheral pain and itch sensitization during ACD. Thus, targeting MrgprD may be an effective method for alleviating itch and pain in ACD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s11658-022-00316-w.

Immunomodulatory and anti-inflammatory efficacy of hederagenin-coated maghemite (γ-Fe2O3) nanoparticles in an atopic dermatitis model

We investigated the immunomodulatory and anti-inflammatory efficacy of hederagenin coating on maghemite (γ-Fe₂O₃) nanoparticles (HM) in atopic dermatitis (AD), as well as the physical and optical properties of maghemite nanoparticles (MP) using SEM, XRD spectroscopy, UV-vis spectra, Raman spectra, and FTIR spectroscopy. Dose-dependent treatment with HM (10, 50, 100, 200 μg/mL) inhibited the expression of Interleukin-2 (IL-2) and Tumor necrosis factor- α (TNF-α) in inflammatory induced HaCaT and Jurkat cells with inflammation caused by TNF/IFN-γ and PMA/A23187. AD model was induced by performing topical application of 2,4-dinitrochlorobenzene (DNCB) and dermatophagoides farinae extract (DFE) for a 31-day period on 8-week-old BALB/c mice. The HM treatments efficiently diminished the AD-like cutaneous lesion induced by DNCB-DFE sensitization in mice. Compared to the AD-only groups, HM treatment considerably attenuated mast cell infiltration and lowered epidermal, and dermal thickness of mice ears skin. In addition, HM treatment prominently alleviated the enlarged size and weight of lymph nodes. Furthermore, HM treatment resulted in a notable reduction in the mRNA expression of Th1 cytokines (TNF-α and IFN-γ), Th2 cytokines (IL-4 and IL-6), Th17 (IL-17), and TSLP. Our data showed that HM provides better AD attenuation compared to MP. Additionally, HM had synergistic effect and act as anti-inflammatory and immunomodulatory agent. Thus, HM shows great potential in AD medication and as a substitution of non-steroid-based medication.

Ferulic Acid Activity in Topical Formulations: Technological and Scientific Prospecting

INTRODUCTION

Ferulic acid is a phenolic compound widely distributed in monocotyledons, with several applications, especially in pharmaceutical and dermo-cosmetic industries. It has proven antioxidant and anti- inflammatory activities, among others, which are mainly ascribed to its molecular structure. The main factor that can lead to serious skin damages like inflammation, dryness, wrinkles, and cancer is the exposure to UV radiation that is responsible for an increased level of radical oxygen species.

OBJECTIVE

This review aims to evaluate the application of ferulic acid in topical formulations and the technologies used to enhance its bioavailability and stability, as well as to get a clearer picture of its effects by in vivo and in vitro studies.

METHODS

It covers technological publications in the WIPO, EPO, INPI, and USPTO databases and scientific publications in the PubMed, Web of Sciences, and Science Direct databases, exploring the trend and application of this compound by country and year of publication.

RESULTS

Both the scientific and technological analyses showed the importance and tendency in the association of the Ferulic Acid and other vitamins and actives. The synergic effect certainly provides a better result, performance, and stability of the compounds, which cleared the great spectrum and applicability of the Ferulic Acid in topical formulations.

CONCLUSION

The present literature survey revealed that ferulic acid exerts an important activity in several formulations for topical application and improved the stability and bioavailability when combined with new technologies and methods, showing an open path to target the treatment of skin disorders.

Challenge of food allergy testing and avoidance in children with atopic dermatitis

Atopic dermatitis (AD) is a common presenting complaint by children and their caretakers to their primary care providers. On testing, children with AD frequently exhibit positive food-specific IgE levels in the absence of immediate allergic reactions. Misinterpretation of these false positive tests can lead to unnecessary food avoidance, which can have tremendous psychosocial, economic and nutritional consequences and, in some cases, facilitate the development of an immediate hypersensitivity to the food. We present a child with persistent AD who underwent broad testing that led to unnecessary food avoidance resulting in Vitamin D deficiency, growth failure and the development of an IgE-mediated food allergy. This case underscores the need for caution by primary care clinicians in using food avoidance diets as a treatment for AD and the importance of limiting allergy testing to foods only when the clinical history indicates an immediate hypersensitivity reaction.

High-Density Lipoprotein (HDL) in Allergy and Skin Diseases: Focus on Immunomodulating Functions

From an evolutionary perspective, lipoproteins are not only lipid transporters, but they also have important functions in many aspects of immunity. High-density lipoprotein (HDL) particles are the most abundant lipoproteins and the most heterogeneous in terms of their composition, structure, and biological functions. Despite strong evidence that HDL potently influences the activity of several immune cells, the role of HDL in allergies and skin diseases is poorly understood. Alterations in HDL-cholesterol levels have been observed in allergic asthma, allergic rhinitis, atopic dermatitis (eczema), psoriasis, urticaria, and angioedema. HDL-associated apolipoprotein (apo) A-I, apoA-IV, and apoC-III, and lyso-phosphatidylcholines potently suppress immune cell effector responses. Interestingly, recent studies provided evidence that allergies and skin diseases significantly affect HDL composition, metabolism, and function, which, in turn, could have a significant impact on disease progression, but may also affect the risk of cardiovascular disease and infections. Interestingly, not only a loss in function, but also, sometimes, a gain in function of certain HDL properties is observed. The objective of this review article is to summarize the newly identified changes in the metabolism, composition, and function of HDL in allergies and skin diseases. We aim to highlight the possible pathophysiological consequences with a focus on HDL-mediated immunomodulatory activities.

Experimental Study of Therapeutic Efficacy of the Topical Preparation «Kourochitin» in Skin Allergy

Background:

The researchers of PIBOC RAS developed the dermo-protective topical drug called «Kourochitin», active substance of which is known quinazoline alkaloid tryptanthrin. In the present work, therapeutic efficacy of this drug in the treatment of allergic dermatosis was evaluated.

Methods:

Dermo-protective action of «Kourochitin» was studied in tow murine models: 2, 4- dinitrofluorobenzene- induced allergic contact dermatitis (ACD) and imiquimod-induced psoriasis.

Results and Discussion:

In a model ACD, it was shown that «Kourochitin» exhibits the curative action on pathophysiological, hematological and immunological parameters in ACD. Namely, «Kourochitin» 1) reduces the level of erythema in the allergen damaged skin area and increases the healing index of the epidermis; 2) normalizes the content of eosinophils, basophils and monocytes in the blood of experimental animals; 3) inhibits the production of main pro-inflammatory cytokines: interleukins - 1 and 2, interferon-gamma, and granulocyte-macrophage colony-stimulating factor. In a murine model of imiquimod-induced psoriasis, it was shown that «Kourochitin» application led to reduction in psoriasis severity on the inflamed epidermis of experimental animals. Additionally, in veterinary research, «Kourochitin»-treatment of canine atopic dermatitis almost completely eliminated signs of allergic manifestations on the epidermis.

Conclusion:

The obtained data suggest that «Kourochitin» as anti-inflammatory, anti-allergic, and wound healing remedy is a potential drug for therapy of various dermatological diseases, in particular allergic skin lesions.

Oral mycobiome identification in atopic dermatitis, leukemia, and HIV patients - a systematic review

INTRODUCTION

Oral mycobiome profiling is important to understand host-pathogen interactions that occur in various diseases. Invasive fungal infections are particularly relevant for patients who have received chemotherapy and for those who have HIV infection. In addition, changes in fungal microbiota are associated with the worsening of chronic conditions like atopic dermatitis (AD). This work aims, through a systematic review, to analyze the methods used in previous studies to identify oral fungi and their most frequent species in patients with the following conditions: HIV infection, leukemia, and atopic dermatitis.

METHODS

A literature search was performed on several different databases. Inclusion criteria were: written in English or Portuguese; published between September 2009 and September 2019; analyzed oral fungi of HIV-infected, leukemia, or AD patients.

RESULTS

21 studies were included and the most identified species was Candida. The predominant methods of identification were morphological (13/21) and sugar fermentation and assimilation tests (11/21). Polymerase chain reaction (PCR) was the most used molecular method (8/21) followed by sequencing techniques (3/21).

CONCLUSIONS

Although morphological and biochemical tests are still used, they are associated with high-throughput sequencing techniques, due to their accuracy and time saving for profiling the predominant species in oral mycobiome.

Efficacy of Sweet Pumpkin in Relieving Contact Dermatitis in Chronically Stressed Rats

Background:

Contact dermatitis (CD) is considered among the common inflammatory skin diseases worldwide. Cucurbita moschata Duchesne has antioxidant, anti-inflammatory, and antidepressant activity beside many other beneficial effects.

Objectives:

This study aimed to assess the effect of pumpkin fruit extract in treating CD in mice exposed to chronic stress and to explore the mechanism through which pumpkin can relief these changes.

Materials and Methods:

Thirty male albino rats were divided into three groups (n = 10); the control and two experimental groups that were exposure to chronic unpredictable mild stress for 4 weeks then painting with 1-fluoro-2,4-dinitrofluorobenzene (DNFB) for 3 consecutive days/week for 2 weeks to induce CD. Biochemical assessment of corticosterone level and antioxidants activity was performed. Skin of affected areas was excised, processed for histopathological examination.

Results:

DNFB-induced CD presented with dryness, hardness, and scaling. There was a significant reduction (P < 0.001) in the levels of superoxide dismutase, glutathione peroxidase and catalase activity in the skin of rats had CD. Histopathologically, the shin showed hyperplastic-thickened epidermis, focal elongation of the rete ridges, inflammatory cells infiltration in the superficial dermis, and increased collagen fibers. Local administration of pumpkin extract significantly increased the antioxidants activity in the skin and alleviated the CD-associated changes.

Conclusions:

This study showed that the pumpkin fruit extract could have a potential in treating CD in stressed conditions mainly via its enhancement of skin antioxidant activity.

Quercitrin, the Main Compound in Wikstroemia indica, Mitigates Skin Lesions in a Mouse Model of 2,4-Dinitrochlorobenzene-Induced Contact Hypersensitivity

Hapten-induced contact hypersensitivity (CHS) is widely utilized to induce immune activation in animal models of allergic contact dermatitis. Our previous findings suggested that the 95% EtOH extract of Wikstroemia indica (L.) C. A. Mey. has antiallergic and anti-inflammatory effects in DNCB-treated CHS SKH-1 hairless mice. The aim of this study was to evaluate the protective effects of compounds isolated from the EtOAc fraction of W. indica in RBL-2H3 cells and 2,4-dinitrochlorobenzene- (DNCB-) induced CHS mice. Of eight compounds in W. indica, that is, umbelliferone, daphnoretin, wikstrocoumarin, (+)-syringaresinol, tricin, (+)-lariciresinol, erythro-guaiacylglycerol-β-coniferyl ether, and quercitrin, quercitrin exhibited the most antiallergic activity against antigen-induced β-hexosaminidase release and IL-4 mRNA expression, which are markers of degranulation in RBL-2H3 cells. After a 7-sensitizing period, 14 days of DNCB treatment with or without topical pimecrolimus (1%) or quercitrin (0.5%) treatment, quercitrin was found to suppress DNCB-induced increases in serum IL-4 and IgE concentrations and transepidermal water loss. These results indicate that quercitrin has therapeutic potential for treatment of allergies and allergy-related contact dermatitis.

Impact of Nutritional Supplementation on Canine Dermatological Disorders

Nutritional supplements, also known as complementary feeds, are products administered with the aim of furnishing health benefits, regardless of nutritional needs. They have been used since ancient times in veterinary dermatology, and a number of studies have focused on investigating the health benefits of some ingredients found in commercially available complementary feed for dogs. The aim of this paper is to review the literature available on the use of nutritional supplementation for the management of canine skin diseases, critically appraising the clinical efficacy of such interventions and summarizing the current state of knowledge. This review highlights how these feeds can be considered useful in the management of dermatological disorders and outlines their beneficial effects in the prevention of dietary deficiencies and treatment of diseases, alone, or in addition to conventional pharmacological therapy. In recent years, nutritional supplements have found increasing potential application in veterinary medicine, and the scientific proofs of their beneficial effects are described in this review.

Potential application of liposomal nanodevices for non-cancer diseases: an update on design, characterization and biopharmaceutical evaluation

Liposomes, lipid-based vesicular systems, have attracted major interest as a means to improve drug delivery to various organs and tissues in the human body. Recent literature highlights the benefits of liposomes for use as drug delivery systems, including encapsulating of both hydrophobic and hydrophilic cargos, passive and active targeting, enhanced drug bioavailability and therapeutic effects, reduced systemic side effects, improved cargo penetration into the target tissue and triggered contents release. Pioneering work of liposomes researchers led to introduction of long-circulating, ligand-targeted and triggered release liposomes, as well as, liposomes containing nucleic acids and vesicles containing combination of cargos. Altogether, these findings have led to widespread application of liposomes in a plethora of areas from cancer to conditions such as cardiovascular, neurologic, respiratory, skin, autoimmune and eye disorders. There are numerous review articles on the application of liposomes in treatment of cancer, which seems the primary focus, whereas other diseases also benefit from liposome-mediated treatments. Therefore, this article provides an illustrated detailed overview of liposomal formulations, in vitro characterization and their applications in different disorders other than cancer. Challenges and future directions, which must be considered to obtain the most benefit from applications of liposomes in these disorders, are discussed.

Insight into interleukin-37: The potential therapeutic target in allergic diseases

Allergic diseases are ubiquitous diseases with detrimental effects on the quality of life of people worldwide. Common allergic diseases include asthma, allergic rhinitis (AR) and allergic dermatitis (AD). Recently, studies have shown that interleukin (IL)-37, a novel cytokine in the IL-1 family, exhibits broad protective properties in various diseases, such as autoimmune diseases and cancer. IL-37 displays its anti-inflammatory effect on diseases by curbing innate and acquired immunity as well as inflammatory reactions. IL-37 functions by forming a complex with IL-18Rα and IL-1R8 extracellularly and can be translocated to the nucleus upon forming a complex with mothers against decapentaplegic homolog 3 (Smad3) intracellularly, thereby affecting gene transcription and signaling pathway activation. In addition, increasing evidence confirms that IL-37 expression is aberrant in asthma, AR and AD, which indicates that IL-37 may also play essential roles in allergic diseases. Furthermore, accumulating data obtained from recombinant IL-37 (rIL-37)-treated mice and from IL-37 transgenic (IL-37tg) mice suggest a protective role for IL-37. This review will detail the role of IL-37 in the occurrence and development of allergic diseases and discuss the potential of IL-37 as a therapeutic target in allergic diseases.

The relationship between Toxocara species seropositivity and allergic skin disorders: a systematic review and meta-analysis

We performed a systematic review and meta-analysis on observational studies to evaluate the possible associations between Toxocara species seropositivity and allergic skin disorders (ASDs). We searched the MEDLINE, ScienceDirect, Scopus, Web of Science and Google Scholar databases to 15 May 2018 to identify the relevant studies. We used a random effects meta-analysis model to generate the pooled odds ratio (OR) and 95% confidence intervals (CIs). Fifteen studies, including eight studies with a case-control design (735 patients and 1342 controls) and seven studies with a cross-sectional design (a total of 4804 participants, 1302 individuals with ASDs and 3502 without ASDs), were included in the meta-analysis. We found an increased risk for ASDs in individuals with Toxocara seropositivity (OR 1.75 [95% CI 1.16 to 2.64]). Subanalysis showed that Toxocara seropositivity was significantly associated with urticaria (OR 2.97 [95% CI 1.53 to 5.76]), however, it was not significantly associated with atopy (OR 1.08 [95% CI 0.55 to 2.15]) and eczema (OR 1.62 [95% CI 0.95 to 2.78]). Moreover, the pooled ORs were 2.34 (95% CI 1.32 to 4.15) and 1.27 (95% CI 0.69 to 2.35) for case-control and cross-sectional studies, respectively. The results of our study support hypotheses regarding the existence of a positive relationship between Toxocara infection and allergic disorders, although this association should be further investigated by longitudinal and mechanism studies.

Ameliorative Effect Of Zinc Oxide Nanoparticles Against Dermal Toxicity Induced By Lead Oxide In Rats

Background

Recently, several studies demonstrate the possible role of zinc oxide (ZnO) in the protection of several skin diseases, but less is known about the role of ZnO nanoparticles in the inflammatory skin disease. So, this study was designed to confirm the pivotal role of the nano zinc oxide cream in the alleviation of lead oxide (PbO) induced-allergic dermatitis in rats.

Materials and methods

Two concentrations (1% and 6%) of ZnONPs creams were prepared and characterized prior to being used in the study. A total number of 30 male Wistar rats were randomly divided into six groups. Group 1 (negative control), groups 2&3 (either 1% or 6% ZnONPs control groups), group 4 (PbO), groups 5&6 (co-treatment of each ZnONPs concentration+PbO). All rats in different groups were observed daily to determine the severity of dermal gross lesions. Histopathological studies, mRNA analysis, and oxidative stress evaluations were performed on the affected skin tissue. Immunohistochemical studies were performed to evaluate the expression of cluster of differentiation CD4, CD8 and intercellular adhesion molecules ICAM-1 in different groups.

Results

PbO caused extensive skin oxidative damage manifested by a significant increase in MDA level with a decrease in GSH content and CAT activity. The results of histopathological and immunohistochemical examinations revealed that topical application of PbO for 14 days led to severe allergic dermatitis with remarkable elevations in the number of CD4+ T-helper, CD8+ T-cytotoxic lymphocytes, and ICAM-1 expression. On the other hand, noticeable improvements were recorded in all the previous toxicopathological parameters among the groups treated by either 1% or 6% ZnO-NPs cream. However, the best results were observed in the group treated with 1% ZnO-NPs cream.

Conclusion

Our findings suggest that 1% of ZnO-NPs cream is safe when applied topically on the inflamed skin. Moreover, it had anti-inflammatory and antioxidant effects so that, it is recommended to use the 1% ZnO-NPs cream to avert the dermal toxicity-induced by PbO.

The 21st Century movement within the area of skin sensitization assessment: From the animal context towards current human-relevant in vitro solutions

In a regulatory context, skin sensitization hazard and risk evaluations of manufactured products and their ingredients (e.g. cosmetics) are mandatory in several regions. Great efforts have been made within the field of 21st Century Toxicology to provide non-animal testing approaches to assess the skin allergy potential of materials (e.g. chemicals, mixtures, nanomaterials, particles). Mechanistic understanding of skin sensitization process through the adverse outcome pathway (AOP) has promoted the development of in vitro methods, demonstrating accuracies superior to the traditional animal testing. These in vitro testing approaches are based on one of the four AOP key events (KE) of skin sensitization: formation of immunogenic hapten-protein complexes (KE-1 or the molecular initiating event, MIE), inflammatory keratinocyte responses (KE-2), dendritic cell activation (KE-3), and T-lymphocyte activation and proliferation (KE-4). This update provides an overview of the historically used in vivo methods as well as the current in chemico and in cell methods with and without OECD guideline designations to analyze the progress towards human-relevant in vitro test methods for safety assessment of the skin allergenicity potential of materials. Here our focus is to review 96 in vitro testing approaches directed to the KEs of the skin sensitization AOP.

Allergy and related clinical symptoms among medical students and interns

OBJECTIVES

To determine the prevalence, types, clinical presentations, triggers, and predictors of allergic disorders among medical students and interns at King Abdulaziz University (KAU), Jeddah, Saudi Arabia.

METHODS

A cross-sectional design was used for this study in which 600 medical students and interns were selected by a multistage stratified random sampling. A validated, confidential, self-administered questionnaire was used during 2016 / 2017. It asked about the previous diagnosis of allergic disorders, associated factors, types, clinical symptoms and the triggering allergenic. Descriptive & inferential statistics were done and logistic regression analysis was conducted.

RESULTS

The overall prevalence of diagnosed allergic disorder(s) among the participants was 36.2%.The commonest types of allergy were skin (33.8%) followed by respiratory (29.5%) presentations. The most frequently reported allergenic triggers were the house dust (45.6%) and smoke (30.4%). The first allergy predictor was family history of allergic disorders (aOR= 4.35, 95 % CI: 2.96-6.39), followed by female gender. Regarding the outcome of allergy on students' life, 16.1% occasionally missed classes, and 28.6% had sleep disturbance during allergic attacks.

CONCLUSION

Allergy represents an important problem among medical students and interns. Family history and female gender were the predictors of allergy. Skin and respiratory allergies were the most common types. House dust and smoke were the commonest allergenic triggers. Detection of allergens and management of cases of allergy among medical students and interns are needed. Education and conduction of awareness campaigns about allergy are needed.

Treatment of Life-Threatening ACE-Inhibitor-Induced Angioedema

Incidence of angioedema associated with angiotensin-converting enzyme inhibitors (ACE-I) has been estimated at 0.1%-2.2% of patients receiving treatment. Despite the potential severity of this disease state, standardized treatment is lacking. Traditional pharmacotherapy options include medications that target inflammatory mediators and the angiotensin pathway. However, because ACE-I-induced angioedema is caused by accumulation of bradykinin, these medications fail to target the underlying pathophysiology. Recently, novel therapies that target the kallikrein-bradykinin pathway have been studied. These include icatibant, ecallantide, C1 esterase inhibitors, and fresh-frozen plasma. Recent randomized controlled trials exhibit contradictory results with the use of icatibant. This is a focused review on traditional and novel treatment strategies for ACE-I-induced angioedema.

Korean red ginseng water extract alleviates atopic dermatitis-like inflammatory responses by negative regulation of mitogen-activated protein kinase signaling pathway in vivo

Atopic dermatitis (AD) is a chronic inflammatory skin disease. Korean red ginseng is a Korean traditional medicine. In this study, we estimated the effects of Korean red ginseng water extract (RGE) in the 1-chloro-2,4-dinitrobenzene (DNCB)-induced BALB/c mouse model which develops AD-like lesions. After RGE administration (100, 200, and 400 mg/kg) to DNCB-induced mice there were improvements in the dermatitis score and skin pH, a decrease in trans-epidermal water loss, and improved skin hydration. RGE also significantly inhibited eosinophil infiltration, increased filaggrin protein levels, and decreased serum IgE levels, epidermal thickness, mast cell infiltration, and ceramidase release. Compared with that in DNCB-induced mice, RGE effectively decreased the mRNA expression levels of interleukin-6 (IL-6), thymic stromal lymphopoietin (TSLP), and tumor necrosis factor-α (TNF-α), as well as the protein level of thymus and activation-regulated chemokine (TARC). These inhibitory RGE effects are mediated by inhibiting the phosphorylation of mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 MAPK. Furthermore, we confirmed that RGE suppresses interferon-γ (IFN-γ) and TNF-α-induced expression of macrophage-derived chemokine (MDC) and TARC genes in human keratinocyte (HaCaT) cells. Taken together, these results demonstrate that RGE may exert anti-atopic related to responses by suppression the expression of inflammatory mediators, cytokines, and chemokines via downregulation of MAPK signaling pathways, suggesting that RGE may be an effective therapeutic approach for prevention of AD-like disease.

Autologous whole-blood or autologous serum acupoint injection therapy for chronic urticaria: A systematic review protocol

BACKGROUND

Chronic urticaria (CU) is a common and easily recurring skin disease in the world. Many trials have shown that autologous whole-blood or autologous serum acupoint injection therapy is effective in treating CU. There is currently no systematic review of this therapy. The program aims to evaluate the effectiveness and safety of this therapy in patients with CU.

METHODS

Literature search will be conducted at Medline, PubMed, Excerpt Medica Database, Springer, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Chinese Scientific Journal Database, and other databases. The search date is until May 2019. We will search for popular terms including CU and this therapy. Import the literature electronically. Duplicate documents will be deleted. The primary outcome is the urticaria activity score or other validated scales. Secondary outcomes included response rate, quality of life scale, recurrence rate, and adverse events. A systematic review and search for a randomized controlled trial of this therapy for CU. Implement the Cochrane RevMan V5.3 bias assessment tool to assess bias assessment risk, data integration risk, meta-analysis risk, and subgroup analysis risk (if conditions are met). The mean difference, standard MD, and binary data will be used to represent continuous results.

RESULTS

This study will provide a comprehensive review of the available evidence for the treatment of CU with this therapy.

CONCLUSION

This study will provide new evidence for assessing the effectiveness and side effects of this therapy for CU. Since the data is not individualized, there is no need for formal ethical approval.

PROSPERO REGISTRATION NUMBER

CRD42019128364.

Anti-Atopic Dermatitis Effect of Seaweed Fulvescens Extract via Inhibiting the STAT1 Pathway

Seaweed fulvescens (SF) is a green alga rich in chlorophyll with unique flavor and taste. It is also called Maesaengi which has antioxidant and other physiological activities. In the present study, we evaluated the therapeutic effects of SF in a mouse model of Dermatophagoides farinae body-induced atopic dermatitis (AD) and in tumor necrosis factor-α and interferon-γ-stimulated HaCaT keratinocytes. SF treatment (200 mg/mouse) inhibited the development of AD symptoms, compared to that in the control group, as evidenced from the improved dorsal skin lesion, reduced thickness and infiltration of inflammatory cells and smaller lymph nodes, and reduced levels of proinflammatory cytokines. In HaCaT keratinocytes, SF (10, 25, and 50 μg/mL) suppressed the production of proinflammatory cytokines in a dose-dependent manner. In addition, SF reduced the phosphorylation of signal transducer and activator of transcription 1, which is one of the major signaling molecules involved in cellular inflammation. These results suggested that SF could be a potential therapeutic alternative for the treatment of AD.

The Protective Effect of Violaxanthin from Nannochloropsis oceanica against Ultraviolet B-Induced Damage in Normal Human Dermal Fibroblasts

Skin photoaging, which is mainly induced by ultraviolet B (UVB) radiation, is prevented by the application of UV-protective agents. The microalga Nannochloropsis oceanica (N. oceanica) has been primarily reported as a potential biofuel; however, in this study, we investigated whether N. oceanica extracts exerted photoprotective effects against UVB-irradiated human dermal fibroblasts (HDFs) and which single component was responsible for the protective effect of the extracts. Two extracts-pigment and nonpigment-were prepared from N. oceanica biomass. WST-1 assay and expression analysis of interleukin genes showed that the pigment extracts were not significantly cytotoxic to HDFs. Further experiments revealed that treatment with the pigment extract upregulated the expression of collagen genes and significantly blocked UVB-induced damage such as decreased cell viability and increased ROS production. Next, to investigate the pigment composition of the extracts, HPLC analysis was conducted and violaxanthin was identified as the major pigment. The UVB photoprotective effect of the pigment extracts was confirmed in violaxanthin-treated HDFs. In addition, violaxanthin significantly attenuated UVB-induced G1 phase arrest, senescence-associated β-galactosidase activation, p16 and p21 upregulation, ERK phosphorylation and the downregulation of ECM molecules in HDFs. Therefore, we concluded that violaxanthin was a potential antiphotoaging agent.

Urticaria and angioedema

Urticaria (hives) is a common disorder that often presents with angioedema (swelling that occurs beneath the skin). It is generally classified as acute or chronic. Second-generation, non-sedating, non-impairing histamine type 1 (H1)-receptor antihistamines represent the mainstay of therapy for both acute and chronic urticaria. Angioedema can occur in the absence of urticaria and can be broadly divided into histamine-mediated and non-histamine-mediated angioedema. Histamine-mediated angioedema can be allergic, pseudoallergic or idiopathic. Non-histamine mediated angioedema is largely driven by bradykinin and can be hereditary, acquired or drug-induced, such as with angiotensin-converting enzyme inhibitors. Although bradykinin-mediated angioedema is often self-limited, laryngeal involvement can lead to fatal asphyxiation. The mainstay of management for angioedema is to avoid specific triggers, if possible. For hereditary angioedema, there are specifically licensed treatments that can be used for the management of acute attacks, or for prophylaxis in order to prevent attacks. In this article, the authors will review the causes, diagnosis and management of urticaria (with or without angioedema) and isolated angioedema. The diagnostic and therapeutic approaches to these two conditions are considerably different, and this review is designed to highlight these differences to the reader.

Atopic dermatitis

Atopic dermatitis (AD) is a common, chronic skin disorder that can significantly impact the quality of life of affected individuals as well as their families. Although the pathogenesis of the disorder is not completely understood, it appears to result from the complex interplay between defects in skin barrier function, environmental and infectious agents, and immune dysregulation. There are no diagnostic tests for AD; therefore, the diagnosis is based on specific clinical criteria that take into account the patient's history and clinical manifestations. Successful management of the disorder requires a multifaceted approach that involves education, optimal skin care practices, anti-inflammatory treatment with topical corticosteroids and/or topical calcineurin inhibitors, the management of pruritus, and the treatment of skin infections. Systemic immunosuppressive agents may also be used, but are generally reserved for severe flare-ups or more difficult-to-control disease. Topical corticosteroids are the first-line pharmacologic treatments for AD, and evidence suggests that these agents may also be beneficial for the prophylaxis of disease flare-ups. Although the prognosis for patients with AD is generally favourable, those patients with severe, widespread disease and concomitant atopic conditions, such as asthma and allergic rhinitis, are likely to experience poorer outcomes.

Stigmasterol Alleviates Cutaneous Allergic Responses in Rodents

The therapeutic potential of stigmasterol, a natural steroid alcohol with established immune-modulatory properties, was assessed on allergic cutaneous responses. We examined its suppressive effect on immunoglobulin E (IgE)-mediated active cutaneous anaphylaxis (ACA), compound 48/80 (C48/80)-induced pruritus, and irritant dermatitis induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). Stigmasterol at 10–100 mg/kg significantly inhibited ACA with reduction in reaction area and concentration of the extravasated Evans blue dye. Given at 50 and 100 mg/kg, stigmasterol significantly inhibited C48/80-induced scratching behaviour when compared to saline-treated C48/80-injected control. Skin histopathology of injected sites confirmed that stigmasterol reduced mast cell trafficking and degranulation associated with C48/80-induced pruritus. Stigmasterol controlled inflammatory features such as ear skin oedema and neutrophilia and also reduced serum levels of TNFα induced by topical application of TPA. Epidermal layer thickening and inflammatory cell infiltration of ear skin tissue were significantly reduced by stigmasterol. Taken together, stigmasterol demonstrates significant potential as a molecule of interest in allergic skin disease therapy.

Oral Aspects Identified in Atopic Dermatitis Patients: A Literature Review

Introduction:

Atopic dermatitis is a chronic inflammatory skin condition that is more prevalent in children (10-20% of the world's population) than in adults. As its etiology is multifactorial, it is important to know the most frequent oral manifestations in atopic dermatitis patients.

Methodology:

In the last decades, the correlation between atopic dermatitis and conditions and/or changes in the oral cavity has been demonstrated by several studies. The objective of this paper was to describe, through a review of the literature, the oral health conditions and/or oral aspects identified in patients with atopic dermatitis.

Search Strategy:

A descriptive literature review was carried out through a bibliographical survey based on the last 10 years, in order to answer the study questions.

Results:

As a result, we found six studies with different sample sizes, ranging from 43 to 468 patients, and the majority of them were of cross-sectional study design.

Discussion:

Two studies performed their analysis through dental exams and reported that patients with atopic dermatitis tend to have a greater frequency of carious lesions, and two studies correlated Candida with atopic dermatitis through mycological analyzes.

Conclusion:

There are a few studies in the literature that identify the oral aspects of atopic dermatitis. More investigations are needed in order to contribute to the knowledge of such oral aspects and the approach to treat these patients regarding oral health.

Predicting skin sensitizers with confidence - Using conformal prediction to determine applicability domain of GARD

GARD - Genomic Allergen Rapid Detection is a cell based alternative to animal testing for identification of skin sensitizers. The assay is based on a biomarker signature comprising 200 genes measured in an in vitro model of dendritic cells following chemical stimulations, and consistently reports predictive performances ~90% for classification of external test sets. Within the field of in vitro skin sensitization testing, definition of applicability domain is often neglected by test developers, and assays are often considered applicable across the entire chemical space. This study complements previous assessments of model performance with an estimate of confidence in individual classifications, as well as a statistically valid determination of the applicability domain for the GARD assay. Conformal prediction was implemented into current GARD protocols, and a large external test dataset (n = 70) was classified at a confidence level of 85%, to generate a valid model with a balanced accuracy of 88%, with none of the tested chemical reactivity domains identified as outside the applicability domain of the assay. In conclusion, results presented in this study complement previously reported predictive performances of GARD with a statistically valid assessment of uncertainty in each individual prediction, thus allowing for classification of skin sensitizers with confidence.

Making Sense of Metal Allergy and Hypersensitivity to Metallic Implants in Relation to Hand Surgery

All metals implanted into a biological system undergo some degree of corrosion depending upon its composition. The electrochemical process of corrosion produces free metal ions, which may activate the host's immune system through a variety of mechanisms. Whereas dermal metal hypersensitivity is common, affecting 10% to 15% of the population, the immune reaction from implanted metals is much less common (< 0.1%), but has been associated with metal allergy and hypersensitivity producing a multitude of patient symptoms. Superficial symptoms may be mild to severe forms of dermatitis, urticaria, pruritus, and vasculitis, whereas deep sequelae include metallosis-related pseudotumor, implant loosening, and joint stiffness. Currently, there are clinical tests to evaluate patients for metal hypersensitivity, but there is little agreement regarding the ideal timing and clinical situation prompting the work-up of a patient for a metal allergy or hypersensitivity. An understanding of the epidemiology, etiology, basic science, diagnostic testing, and treatment of patients with suspected metal allergy, as it pertains to the current literature, will aid orthopedic and plastic surgeons of all subspecialties in the management of patients requiring metallic implants.

CXCR5-Overexpressing Mesenchymal Stromal Cells Exhibit Enhanced Homing and Can Decrease Contact Hypersensitivity

Mesenchymal stromal cells (MSCs) can modulate inflammation and contribute to tissue regeneration and, thus, have emerged as a promising option for cell-based therapy. However, the ability of MSCs to migrate to injured tissues still needs to be improved. In this study, we investigated whether genetically engineered MSCs could exhibit increased migratory properties and improved therapeutic efficacy. Using a mouse model of contact hypersensitivity (CHS), chemokine gene expression screening revealed that CXCL13 changed most significantly in injured tissue. Unfortunately, MSCs hardly express the corresponding receptor, CXCR5. Thus, CXCR5-overexpressing MSCs (MSC^CXCR5) were generated that retained their abilities of proliferation, differentiation, and immunomodulation. Furthermore, MSC^CXCR5 showed significantly increased migrating ability toward CXCL13. Importantly, systemic infusion of MSC^CXCR5 dramatically suppressed CHS in mice, as evidenced by decreased levels of inflammatory cell infiltration and pro-inflammatory cytokine production. Numerous MSC^CXCR5 migrated into inflamed ears, localized with T cells, inhibited T cell proliferation, promoted T cell apoptosis, and suppressed the production of T cell-derived pro-inflammatory factors. Collectively, these findings demonstrate that CXCR5 overexpression increases the ability of MSCs to respond to migratory stimuli and highly intensifies their immunomodulatory effects in vivo. This strategy for enhancing targeted stem/progenitor cell homing may improve the efficacy of MSC-based therapies.

Neuronal Fc-epsilon receptor I contributes to antigen-evoked pruritus in a murine model of ocular allergy

Pruritus is the major symptom of ocular allergy but currently available treatments are often ineffective. Previous studies demonstrated that subpopulations of primary sensory neurons express Fc receptors and may contribute to antigen-specific pain. We investigated the role of neuronal Fc-epsilon Receptor I (FcεRI) in allergic ocular pruritus. Ovalbumin (OVA) was used as allergen together with alum adjuvant (OVA+alum) to produce a mouse model of ocular allergy with a significant elevation in the serum levels of both antigen-specific IgE and IgG. Mice sensitized by OVA without alum only induced elevation of serum IgG but not IgE. Scratching behavior toward the eyes with the hindlimb was used as an indicator of ocular itch. Topical OVA challenging to the eye dose-dependently induced scratching toward the eye in the OVA+alum sensitized mice, but not those sensitized by OVA only. The antigen-induced scratching was largely abolished by topical application of the blocking antibody to FcεRIα, but was only partially alleviated by pretreatment of mast cell stabilizer or histamine I receptor antagonist. The expression of FcεRI was detected in subpopulations of trigeminal ganglion (TG) neurons including those expressing pruriceptive markers and innervating the conjunctiva in the naïve mice. Moreover, FcεRI was found significantly upregulated in small-sized TG neurons in the OVA+alum sensitized mice. In acutely dissociated TG neurons, IgE-immune complex (IC), but not the antibody or antigen alone, induced intracellular calcium increase. The neuronal responses to IgE-IC could be specifically blocked by pre-application of a siRNA for FcεRIα. Our results indicate that FcεRI expressed on peripheral nociceptive neurons in the TG may be directly activated by IgE-IC and contribute to allergic ocular pruritus. This study may suggest a novel mechanism for the development of pathological itch in allergic diseases.

Mesenchymal Stem Cell Therapy for Inflammatory Skin Diseases: Clinical Potential and Mode of Action

Inflammatory skin disorders that cause serious deterioration of the quality of life have become one of the major public concerns. Despite their significance, there is no fundamental cure to date. Mesenchymal stem cells (MSCs) possess unique immunomodulatory properties which make them a promising tool for the treatment of various inflammatory diseases. Our recent preclinical and clinical studies have shown that MSCs can be successfully used for the treatment of atopic dermatitis (AD), one of the major inflammatory skin diseases. This observation along with similar reports from other groups revealed the efficacy and underlying mechanisms of MSCs in inflammatory dermatosis. In addition, it has been proposed that cell priming or gene transduction can be novel strategies for the development of next-generation high-efficacy MSCs for treating inflammatory skin diseases. We discuss here existing evidence that demonstrates the regulatory properties of MSCs on immune responses under inflammatory conditions.

Therapeutic effects of human gingiva-derived mesenchymal stromal cells on murine contact hypersensitivity via prostaglandin E2-EP3 signaling

BACKGROUND

The immunomodulatory and anti-inflammatory functions of human gingiva-derived mesenchymal stromal cells (GMSCs) have been demonstrated in contact hypersensitivity (CHS) models; however, their therapeutic effect during the late phase of CHS has been poor.

METHODS

The murine CHS model was induced by applying oxazolone to the ears of mice. Mesenchymal stromal cells were applied via two methods (intravenous or local injection) at three time points: 1 day before sensitization, 1 day before challenge, or 1 h after challenge. Prostaglandin E2 (PGE2) and sulprostone were administered subcutaneously 1 h after challenge.

RESULTS

The application of GMSCs, bone marrow mesenchymal stem cells, and adipose-derived stem cells all effectively suppressed CHS; however, GMSC treatment exhibited the greatest efficacy. Local injection of GMSCs led to a more marked attenuation of CHS compared with intravenous injection, especially during the late phase of CHS, and this manifested as decreased infiltration of inflammatory cells, suppression of the levels of various proinflammatory cytokines, reconstruction of the disrupted Th1/Th2 balance, and upregulation of regulatory T cells in the allergen contact areas. Pretreatment with indomethacin significantly abrogated the GMSC-mediated immunosuppressive effects, while PGE2 application reversed the effects of indomethacin pretreatment of GMSCs. Moreover, GMSC administration promoted the expression of EP3, a prostaglandin E receptor, and the application of sulprostone, an agonist of EP3, significantly attenuated CHS to a similar degree as that of GMSC administration.

CONCLUSIONS

GMSCs have reproducible and powerful immunomodulatory functions. Local injection of GMSCs is the superior mode for therapeutic application. PGE2-EP3 signaling plays an important role in the immunomodulatory functions of GMSCs in murine CHS.

Vitamin D in atopic dermatitis, chronic urticaria and allergic contact dermatitis

Vitamin D influences allergen-induced pathways in the innate and adaptive immune system, and its potential immunomodulatory role in allergic skin disorders has been explored. This comprehensive review article provides an overview of the role of vitamin D in three common dermatologic conditions: atopic dermatitis (AD), chronic urticaria, and allergic contact dermatitis (ACD). Whereas the literature regarding vitamin D and AD has resulted in mixed findings, several studies have described an inverse relationship between vitamin D levels and AD severity, and improvement in AD with vitamin D supplementation. Similarly, several studies report an inverse relationship between vitamin D levels and severity of chronic urticaria. Although current research in humans remains limited, an increased likelihood of ACD has been demonstrated in vitamin D-deficient mice. Additional well-designed clinical trials will be necessary to determine whether vitamin D supplementation should be recommended for prevention or adjuvant treatment of these common dermatologic conditions.

Effect of Dangguibohyul-Tang, a Mixed Extract of Astragalus membranaceus and Angelica sinensis, on Allergic and Inflammatory Skin Reaction Compared with Single Extracts of Astragalus membranaceus or Angelica sinensis

Dangguibohyul-tang (DBT), herbal formula composed of Astragalus membranaceus (AM) and Angelica sinensis (AS) at a ratio of 5 : 1, has been used for the treatment of various skin diseases in traditional medicine. We investigated the effect of DBT on allergic and inflammatory skin reaction in atopic dermatitis-like model compared to the single extract of AM or AS. DBT treatment showed the remission of clinical symptoms, including decreased skin thickness and scratching behavior, the total serum IgE level, and the number of mast cells compared to DNCB group as well as the single extract of AM- or AS-treated group. Levels of cytokines (IL-4, IL-6, IFN-γ, TNF-α, and IL-1β) and inflammatory mediators (NF-κB, phospho-IκBα, and phospho-MAPKs) were significantly decreased in AM, AS, and DBT groups. These results demonstrated that AM, AS, and DBT may have the therapeutic property on atopic dermatitis by inhibition of allergic and inflammatory mediators and DBT formula; a mixed extract of AM and AS based on the herb pairs theory especially might be more effective on antiallergic reaction as compared with the single extract of AM or AS.