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Background: Chronic kidney disease‐associated pruritus is a distressing symptom and has a far‐reaching impact on patients' sleep and quality of life for most patients receiving haemodialysis. Traditional therapies have limited effectiveness. Objectives: This study aimed to invent a self‐operated ice roller and evaluate its efficacy in relieving pruritus, sleep quality, and quality of life. Design: This study was experimental with a two‐arm parallel group design. Participants: A convenient sampling method was used to recruit 60 patients receiving haemodialysis who reported pruritus (5D‐Itch Scale score >5) lasting over 4 weeks in Taiwan. The participants were randomly assigned to one of two groups: the intervention group used an ice roller for 7 days, while the control group received no anti‐pruritus treatment. Measurements: This study was experimental with a two‐arm parallel group design. The measurement instruments included the 5D‐Itch Scale, Pittsburgh Sleep Quality Index and WHOQOL‐BREF‐Taiwan Version. The analysis of covariance, chi‐square, Independent t tests, and partial Eta2 (η2p) were used to analyse the data. Results: The participants' mean age was 62.77 years. Application of the ice roller significantly decreased overall pruritus (p <.05; η2p =.09) and distribution of pruritus‐associated bodily parts (p =.03; η2p =.08). There were no statistically significant differences in sleep quality and related indicators between the experimental and control groups at the study endpoint. Regarding quality of life, only the social relationship domain significantly differed between the two groups (p =.02; η2p =.08). Conclusions: The ice roller can decrease pruritus and its distribution in patients receiving haemodialysis, serving as an adjunct therapy alongside conventional anti‐pruritus treatments. [ABSTRACT FROM AUTHOR]

Background: Atopic dermatitis (AD), a highly pruritic, inflammatory skin disease, affects approximately 7% of adolescents globally. A topical formulation of ruxolitinib, a Janus kinase (JAK) 1/JAK2 inhibitor, demonstrated safety and efficacy among adolescents/adults in two phase 3 studies (TRuE-AD1/TRuE-AD2). Objective: To describe safety and efficacy of 1.5% ruxolitinib cream versus vehicle and long-term disease control of ruxolitinib cream among adolescents aged 12–17 years from pooled phase 3 study data. Methods: Patients [≥ 12 years old with AD for ≥ 2 years, Investigator's Global Assessment score (IGA) 2/3, and 3–20% affected body surface area (BSA) at baseline] were randomized 2:2:1 to ruxolitinib cream (0.75%/1.5%) or vehicle for 8 weeks of continuous use followed by a long-term safety (LTS) period up to 52 weeks with as-needed use. Patients originally applying vehicle were rerandomized 1:1 to 0.75%/1.5% ruxolitinib cream. Efficacy measures at week 8 included IGA treatment success (IGA-TS; i.e., score of 0/1 with ≥ 2 grade improvement from baseline), ≥ 75% improvement in Eczema Area and Severity Index (EASI-75), and ≥ 4-point improvement in itch numerical rating scale (NRS4). Measures of disease control during the LTS period included IGA score of 0 (clear) or 1 (almost clear) and percentage affected BSA. Safety was assessed throughout the study. Results: Of 1249 randomized patients, 245 (19.6%) were aged 12–17 years. Of these, 45 patients were randomized to vehicle and 92 patients to 1.5% ruxolitinib cream. A total of 104/137 (75.9%) patients continued on 1.5% ruxolitinib cream in the LTS period [82/92 (89.1%) continued on 1.5% ruxolitinib cream; 22/45 (48.9%) patients on vehicle were reassigned to 1.5% ruxolitinib cream], and 83/104 (79.8%) of these patients completed the LTS period. At week 8, substantially more patients who applied 1.5% ruxolitinib cream versus vehicle achieved IGA-TS (50.6% versus 14.0%), EASI-75 (60.9% versus 34.9%), and NRS4 (52.1% versus 17.4%; P = 0.009). The mean (SD) reduction in itch NRS scores was significantly greater in patients applying 1.5% ruxolitinib cream versus vehicle from day 2 [− 0.9 (1.9) versus −0.2 (1.4); P = 0.03]. During the LTS period, mean (SD) trough steady-state ruxolitinib plasma concentrations at weeks 12/52 were 27.2 (55.7)/15.5 (31.5) nM. The percentage of patients achieving IGA score of 0 or 1 was sustained or further increased with 1.5% ruxolitinib cream; mean affected BSA was generally low (< 3%; i.e., mild disease). Through 52 weeks, application site reactions occurred in 1.8% of adolescent patients applying 1.5% ruxolitinib cream at any time; no patients had serious adverse events. There were no serious infections, malignancies, major adverse cardiovascular events, or thromboembolic events. Conclusions: Meaningful anti-inflammatory and antipruritic effects were demonstrated with 1.5% ruxolitinib cream in the subset of adolescent patients with AD, comparable with those observed in the overall study population; long-term, as-needed use maintained disease control and was well tolerated. Clinical Trial Registration: ClinicalTrials.gov identifiers NCT03745638 (registered 19 November 2018) and NCT03745651 (registered 19 November 2018). [ABSTRACT FROM AUTHOR]

Introduction. Anal contact or conduction in the anal canal and rectum is a common condition in the coloproctological field, occurring in 5% of the population that affects this country. Treatment consists of hygiene and the use of topical steroids, antibacterial and antifungal agents. No generally accepted attitude towards a private person has been developed.Aim. To study the effectiveness of using homeopathic ointment in the treatment of patients with anal itching.Material and methods. A prospective comparative randomized study was conducted in a specialized advisory center of the Clinics of Samara State Medical University. The study included 96 patients with anal itching without fungal infection of the perianal skin and concomitant purulent pathology. In the main group (n = 46), treatment was carried out using homeopathic ointment in the perianal area 2–3 times a day for 14 days. In the control group (n = 50), treatment was carried out with topical steroid ointments 2–3 times a day for 14 days.Results and discussion. From the data obtained on the use of homeopathic ointment, it follows that it is not inferior in effectiveness to topical steroid ointments in reducing symptoms of the disease (Student’s t-test = 0.35; p > 0.05 and Student’s t-test = 0.28; p > 0.05), and by the number of relapses (χ2 = 0.535; p > 0.05).Conclusion. The use of homeopathic ointment for topical application appears to be a promising new treatment for patients with anal itching and is as effective as topical steroid ointments.

Cutaneous T-cell lymphomas are a heterogenous group of lymphomas that cause various skin manifestations. Severe pruritus occurs frequently in cutaneous T-cell lymphoma and negatively impacts patients' quality of life. The pathophysiology of cutaneous T-cell lymphoma-associated itch is complex and involves various immune cells, inflammatory cytokines, and neuroimmune interactions. Treating cutaneous T-cell lymphoma pruritus can be challenging, and there have been few randomized controlled studies evaluating the use of antipruritic treatments in these patients. Systemic therapies targeting the disease have also been shown to have some antipruritic effects. Furthermore, although biologic therapy has revolutionized the treatment of other pruritic skin conditions, the use of biologics in cutaneous T-cell lymphoma remains controversial. [ABSTRACT FROM AUTHOR]

Sophocarpine is a bioactive compound extracted from the dried root of Sophorae Flavesentis Aiton, a plant that has been used for thousands of years for various conditions including skin itch and pain. Its antipruritic and analgesic effects are suggested in publications, while the molecular mechanisms underneath interacting with TRP channels are not understood. We investigated the anti-inflammatory, antipruritic, and analgesic effects of sophocarpine in a murine inflammatory itch and pain model to elucidate the underlying mechanisms. We evaluated sophocarpine's anti-pruritic and analgesic effects by monitoring mice's scratching and wiping behaviors, and the anti-inflammatory effect by measuring psoriasis area and severity index (PASI) score. The mRNA and protein expression of TRPA1/TRPV1 was analyzed by real-time quantitative polymerase chain reaction and western blotting. We further investigated the relationship between sophocarpine and TRPA1/TRPV1 in mice administered allyl-isothiocyanate (AITC) or capsaicin and by molecular docking. We found that sophocarpine decreased scratching bouts, wipes, and the PASI score, reduced the TNF-α and IL-1β in the skin and TRPA1 and TRPV1 in the trigeminal ganglion. Pretreatment of sophocarpine decreased AITC-induced scratching bouts and wipes and capsaicin-induced wipes. We also found potential competitive bindings between sophocarpine and AITC/capsaicin to TRPA1/TRPV1. Sophocarpine is a potential competitive inhibitor of TRPA1 and TRPV1 channels eliciting strong anti-inflammatory, anti-pruritic, and analgesic effects, suggesting its significant therapeutic potential in treating diseases with inflammatory itch and pain. [Display omitted] • Sophocarpine effectively treats inflammatory itch and pain in a murine ACD model. • Sophocarpine downregulates mRNA of TRPV1/A1 to ameliorate itch and pain in vivo. • Sophocarpine may bind to TRPV1/A1 to ameliorate itch and pain in silico. [ABSTRACT FROM AUTHOR]

Females demonstrate heightened central sensitization (CS), a risk factor for chronic pain characterized by enhanced responsivity of central nervous system nociceptors to normal or subthreshold input. Sleep disruption increases pain sensitivity, but sex has rarely been evaluated as a moderator and few experiments have measured CS. We evaluated whether two nights of sleep disruption alter CS measures of secondary hyperalgesia and mechanical temporal summation in a sex-dependent manner. We also evaluated differences in measures of pain sensitivity. Seventy-nine healthy adults (female n = 46) participated in a randomized crossover experiment comparing two consecutive nights of eight pseudorandomly distributed forced awakenings (FA [-200 min sleep time]) against two nights of undisturbed sleep (US). We conducted sensory testing the mornings following Night 2; the heat-capsaicin pain model was used to induce secondary hyperalgesia. FA reduced total sleep time (REM and NREM Stage 3) more profoundly in males. We observed divergent, sex-dependent effects of FA on secondary hyperalgesia and temporal summation. FA significantly increased secondary hyperalgesia in males and significantly increased temporal summation in females. Sex differences were not attributable to differential sleep loss in males. FA also significantly reduced heat-pain threshold and cold pressor pain tolerance, independently of sex. Sleep disruption enhances different pain facilitatory measures of CS in males and females suggesting that sleep disturbance may increase risk for chronic pain in males and females via distinct pathways. Findings have implications for understanding sex differences in chronic pain and investigating sleep in chronic pain prevention efforts.

Menthol contributes to poor cessation rates among smokers, in part because menthol enhances nicotine reward and reinforcement. Mentholated tobacco products contain (-)-menthol and (+)-menthol, in varying proportions. We examined these two menthol stereoisomers for their ability to upregulate α4β2 nAChRs and to alter dopamine neuron firing frequency using long-term, low-dose (≤500 nm) exposure that is pharmacologically relevant to smoking. We found that (-)-menthol upregulates α4β2 nAChRs while (+)-menthol does not. We also found that (-)-menthol decreases dopamine neuron baseline firing and dopamine neuron excitability, while (+)-menthol exhibits no effect. We then examined both stereoisomers for their ability to inhibit α4β2 nAChR function at higher concentrations (>10 µm) using the Xenopus oocyte expression system. To probe for the potential binding site of menthol, we conducted flooding simulations and site-directed mutagenesis. We found that menthol likely binds to the 9´ position on the TM2 (transmembrane M2) helix. We found that menthol inhibition is dependent on the end-to-end distance of the side chain at the 9´ residue. Additionally, we have found that (-)-menthol is only modestly (∼25%) more potent than (+)-menthol at inhibiting wild-type α4β2 nAChRs and a series of L9´ mutant nAChRs. These data reveal that menthol exhibits a stereoselective effect on nAChRs and that the stereochemical effect is much greater for long-term, submicromolar exposure in mice than for acute, higher-level exposure. We hypothesize that of the two menthol stereoisomers, only (-)-menthol plays a role in enhancing nicotine reward through nAChRs on dopamine neurons.

In our article in the last issue, What is an emollient and what does it do?, we looked at the basics of emollient therapy and how they helped skin. The article discussed the different types of emollient formulation available (such as gels, creams, and ointments) and how they differed in terms of patient acceptability. Finally, it looked at the importance of patient choice, and how harnessing that could improve patient concordance to facilitate the optimum outcome for both patient and prescriber -- namely, regular application. This second article discusses how this knowledge could be used to make clinical decisions around emollient choice, and how to decide which emollient might best suit a particular patient. It will consider some of the different ingredients used in emollients, and how these different ingredients lead to slightly different emollient qualities which might suit particular age ranges and severity of skin. The article will pay particular attention to the properties and use of Hydromol Cream. [ABSTRACT FROM AUTHOR]

The article provides a framework for infectious disease clinicians in the evaluation and management of patients with delusional infestation. Topics discussed include initial workup in a clinical visit, reason that the treatment of delusional infestation is notable challenging, and the mainstay of delusional infestation management.

Hepatic pruritus is common in liver conditions, including cholestasis and nonalcoholic fatty liver disease. The pruritus can be severe enough to diminish sleep and decrease quality of life. The pathophysiology likely involves many molecules and receptors, including bile acids, bilirubin, lysophosphatidic acid (LPA), endogenous opioids, and serotonin. Recent advances suggest a significant role of Mas-related G protein-coupled receptor X4 (MRGPRX4) and autotaxin/LPA as key players in cholestatic pruritus. Further research is needed to develop increasingly targeted therapies with greater efficacy, especially given that many patients report itch refractory to various treatments. Cholestyramine was the only US FDA-approved drug for cholestatic pruritus until recent approval of ileal bile acid transporter (IBAT) inhibitors for use in the pediatric cholestatic conditions, progressive familial intrahepatic cholestasis and Alagille syndrome. Both medications decrease the bile acid pool. IBAT inhibitors are under investigation for broader use, and targeting LPA receptors and MRGPR4 are additional attractive options. [ABSTRACT FROM AUTHOR]

BackgroundDespite recent insights into the pathophysiology of acute and chronic itch, chronic itch remains an often intractable condition. Among major contributors to chronic itch is dysfunction of spinal cord gamma aminobutyric acidergic (GABAergic) inhibitory controls.ObjectivesWe sought to test the hypothesis that selective GABA agonists as well as cell transplant-derived GABA are antipruritic against acute itch and in a transgenic mouse model of atopic dermatitis produced by overexpression of the TH2 cell-associated cytokine, IL-31 (IL-31Tg mice).MethodsWe injected wild-type and IL-31Tg mice with combinations of GABA-A (muscimol) or GABA-B (baclofen) receptor agonists 15 to 20 minutes prior to injection of various pruritogens (histamine, chloroquine, or endothelin-1) and recorded spontaneous scratching before and after drug administration. We also tested the antipruritic properties of intraspinal transplantation of precursors of GABAergic interneurons in the IL-31Tg mice.ResultsSystemic muscimol or baclofen are antipruritic against both histamine-dependent and -independent pruritogens, but the therapeutic window using either ligand alone was very small. In contrast, combined subthreshold doses of baclofen and muscimol produced a significant synergistic antipruritic effect, with no sedation. Finally, transplant-mediated long-term enhancement of GABAergic signaling not only reduced spontaneous scratching in the IL-31Tg mice but also dramatically resolved the associated skin lesions.ConclusionsAlthough additional research is clearly needed, existing approved GABA agonists should be considered in the management of chronic itch, notably atopic dermatitis.

Atopic dermatitis (AD) is a chronic, relapsing inflammatory skin disorder affecting 15–20% of children and 1–10% of adults. Staphylococcus aureus (S. aureus) infection is the most frequent complication of AD and is involved in the worsening of the disease. Systemic and topical antibiotics are used in the treatment for AD but there are concerns over increasing resistance. Bleach (sodium hypochlorite, NaOCl) baths are an inexpensive, widely accessible, alternative antibiotic treatment that may not worsen antibiotic resistance. Bleach baths are used as adjunctive treatment in AD patients to treat superinfections, although their mechanism of action is not well understood. Balancing safety concerns with efficacious treatment should be important especially for AD where the majority of patients are in pediatrics age groups. Studies available in PubMed databases were included in this review. Most suggested bleach bath improves clinical symptoms of AD and restores surface microbiome by eradicating bacteria, most notably S. aureus. Some studies have noted that this antimicrobial effect has reduced the need for topical corticosteroids. In addition, bleach seems to have strong anti-inflammatory and antipruritic effects. Overall, bleach baths seem to be safe on human skin, without disrupting the epidermal barrier function. The review concluded, although there are some advantages of use of bleach baths, more studies to investigate long-term efficacy and safety of bleach baths are required before fixing its role in the treatment of AD especially in the context of the Indian scenario. [ABSTRACT FROM AUTHOR]

Itch is relayed to higher centers by projection neurons in the spinal and medullary dorsal horn. We employed a double-label method to map the ascending projections of pruriceptive and nociceptive trigeminal and spinal neurons. The retrograde tracer fluorogold (FG) was stereotaxically injected into the right thalamus or lateral parabrachial area (LPb) in mice. Seven days later, mice received intradermal (id) microinjection of histamine, chloroquine, capsaicin, or vehicle into the left cheek. Histamine, chloroquine, and capsaicin intradermally elicited similar distributions of Fos-positive neurons in the medial aspect of the superficial medullary and spinal dorsal horn from the trigeminal subnucleus caudalis to C2. Among neurons retrogradely labeled from the thalamus, 43%, 8%, and 22% were Fos-positive following id histamine, chloroquine, or capsaicin. Among the Fos-positive neurons following pruritic or capsaicin stimuli, ∼1-2% were retrogradely labeled with FG. Trigeminoparabrachial projection neurons exhibited a higher incidence of double labeling in the superficial dorsal horn. Among the neurons retrogradely labeled from LPb, 36%, 29%, and 33% were Fos positive following id injection of histamine, chloroquine, and capsaicin, respectively. Among Fos-positive neurons elicited by id histamine, chloroquine, and capsaicin, respectively, 3.7%, 4.3%, and 4.1% were retrogradely labeled from LPb. The present results indicate that, overall, relatively small subpopulations of pruriceptive and/or nociceptive neurons innervating the cheek project to thalamus or LPb. These results imply that the vast majority of pruritogen- and algogen-responsive spinal neurons are likely to function as interneurons relaying information to projection neurons and/or participating in segmental nocifensive circuits.

The objective of this randomised, double blinded clinical trial was to evaluate the efficacy of prophylactic administration of 4 mg ondansetron as monotherapy versus combination therapy of 4 mg ondansetron plus 8 mg dexamethasone for the prevention of intrathecal morphine-associated pruritus in caesarean section within 24 h. A total of 194 patients were included, 96 patients in the monotherapy group and 98 in the combination group. One hour after the operation, 11.5% of patients in ondansetron group had failure of prophylaxis for pruritus compared to 13.5% of patients in the combination group (p =.66). This decreased throughout the follow-up to reach 0.0% and 1.0% at 24 h in the ondansetron vs. the combination groups respectively. There was no superiority of combining ondansetron with dexamethasone over the use of ondansetron as prophylactic antipruritic in parturients receiving intrathecal morphine for caesarean section. What is already known on this subject? The incidence of pruritus has been reported to be between 36% and 60% in patients undergoing caesarean section with intrathecal morphine. Ondansetron has been identified as possible antipruritic agent while the antipruritic effect of dexamethasone is inconclusive. What do the results of this study add? The study demonstrated that there was no superiority of combining ondansetron with dexamethasone over the use of ondansetron as prophylactic antipruritic in parturients receiving intrathecal morphine for caesarean section. Moreover, it seems that there is no effect of combining ondansetron with dexamethasone over ondansetron alone on antiemetic consequences. What are the implications of these findings for clinical practice and/or further research? Ondansetron could be an effective antipruritic if used solely for patients undergoing caesarean section. [ABSTRACT FROM AUTHOR]

The kappa-opioid agonist, nalfurafine, has been approved in Japan for treatment of itch in patients with chronic kidney disease. We presently investigated if systemic administration of nalfurafine inhibited ongoing or touch-evoked scratching behavior (alloknesis) following acute intradermal injection of histamine or the non-histaminergic itch mediator, chloroquine, in mice. We also investigated if nalfurafine suppressed spontaneous or touch-evoked scratching in an experimental model of chronic dry skin itch. Nalfurafine reduced scratching evoked by histamine and chloroquine. Following acute histamine, but not chloroquine, low-threshold mechanical stimuli reliably elicited directed hindlimb scratching behavior, which was significantly attenuated by nalfurafine. In mice with experimental dry skin, nalfurafine abolished spontaneous scratching but had no effect on alloknesis. Nalfurafine thus appears to be a promising treatment for acute itch as well as ongoing itch of dry skin.

To identify triggering factors for the next inflammatory episode of recurrent acute anterior uveitis (RAAU), a 1:1 case–control study was conducted. We interviewed RAAU patients with recent acute anterior uveitis attack and quiescent controls for their information during a previous month using Srithanya Stress Test (ST-5) and questionnaires about potential triggering factors. Asymptomatic controls were matched for age (± 5 years), sex, and HLA-B27. There were 39 pairs of cases and controls. Patients who recently experienced a uveitis attack demonstrated higher mean ST-5 scores (3.7 ± 2.9 vs 0.7 ± 1.1) and shorter sleep time (6.3 ± 1.4 vs 7.4 ± 0.7 h per day) compared with their controls. In the multivariate conditional logistic regression analysis, ST-5 score ≥ 3 (OR 9.07, 95% CI 1.14–72.16, p = 0.037) and sleep time < 7 h per day (OR 12.12, 95% CI 1.37–107.17, p = 0.025) were more likely to trigger a uveitis attack in RAAU accounted for patients' age, sex, HLA- B27 positivity, and presence of concurrent anti-inflammatory drugs for co-existing diseases. Other suspected triggering factors were not found to have any significant association. In short, stress and inadequate sleep may lead to the future episode of acute anterior uveitis in RAAU. Both physical and emotional stress management should be advised to RAAU patients to minimize recurrences and further complications. [ABSTRACT FROM AUTHOR]

Corneal neovascularization (CNV) causes higher-order aberrations, corneal edema, ocular inflammation, and corneal transplant rejection, thereby decreasing visual acuity. In this study, we investigated the effects of topical administration of the kappa opioid receptor agonist nalfurafine (TRK-820) on CNV. To induce CNV, intrastromal corneal sutures were placed on the corneal stroma of BALB/c mice for 2 weeks. Nalfurafine (0.1 µg/2 μL/eye) was topically administered to the cornea once or twice daily after CNV induction. The CNV score, immune cell infiltration, and mRNA levels of angiogenic and pro-inflammatory factors in neovascularized corneas were evaluated using slit-lamp microscopy, immunohistochemistry, flow cytometry, and polymerase chain reaction. The mRNA expression of the kappa opioid receptor gene Oprk1 was significantly upregulated following CNV induction. Topical administration of nalfurafine twice daily significantly suppressed CNV and lymphangiogenesis, as well as reduced the mRNA levels of angiogenic and pro-inflammatory factors in the neovascularized corneas. Moreover, nalfurafine administration twice daily reduced the numbers of infiltrating leukocytes, neutrophils, macrophages, and interferon-γ-producing CD4+ T cells in the neovascularized corneas. In this study, we demonstrated that topical administration of nalfurafine suppressed local CNV in a mouse model along with the activation of KOR, suggesting that nalfurafine may prevent and control CNV in humans. [ABSTRACT FROM AUTHOR]

Introduction: Uremic pruritus (UP) is one of the major complaints in hemodialysis patients without specific treatment. Considering the antipruritic effect of melatonin in atopic dermatitis (AD) and similarities in mechanism between pruritus in AD and UP, this randomized clinical trial designed to evaluate the antipruritic effect of melatonin on hemodialysis patients with UP.Methods: This multicenter double-blind randomized clinical trial was conducted among the hemodialysis patients with UP. Adult patients were randomly assigned to receive two capsules of melatonin 5 mg /d for a 2 weeks period, undergoing a 1 week washout period, and then two capsules of placebo for another 2 weeks period, or the reverse sequence. Visual Analogue Scale (VAS), % affected Body Surface Area (%BSA) and 12-Pruritus Severity Scale questionnaire (12-PSS) were measured before and after each of the three periods. A crossover analysis of variance adjusted by treatment, period and carryover effect was performed by STATA 14.Results: Thirty-nine patients under hemodialysis (mean age of 55.08 ± 12.34 years) completed the study. Mean changes in VAS, 12-PSS, and %BSA after the interventions (melatonin vs. placebo, mean ± SD) were as follows, respectively: -3.21 ± 3.33 vs. -1.38 ± 2.23, -4.59 ± 5.22 vs. -2.08 ± 4.35, and -19.10 ± 30.31 vs. 4.64 ± 29.11 (P < .05). However, the statistical significance of the treatment effect from melatonin was observed, carryover and period effects were not significant (P > .05) for any of the main variables.Conclusion: Based on to the preliminary results of this study, melatonin can be introduced as an effective drug for management of pruritus in uremic patients. [ABSTRACT FROM AUTHOR]

Psoriasis is a chronic immune-mediated inflammatory skin disease, in which pruritus is a common feature and also affects the social well-being of individuals with psoriasis significantly. The transient receptor potential cation channel, subfamily V, member 3 (TRPV3) is believed to be involved in hypersensation and generation of itching in the case of psoriasis. The purpose of the present study was to find out suitable anti-pruritic agents and to establish the mechanism of actions of those anti-pruritic agents with the help of molecular docking studies, through which they can alleviate the itching and hypersensitivity problems in psoriasis. An extensive literature survey, pertaining to natural ligands having reported antipsoriatic activity was carried out. The crystal structure of the TRPV3 receptor was retrieved from rcsb.org. 3D structures of selected eleven natural ligands were prepared and optimized by ChemSketch free version 2015. Computational proteinligand docking studies were carried out by AutoDock 4.2 simulator using the Lamarckian genetic algorithm. In this study, Hypericin showed a higher binding affinity (-8.09 kcal/mol) and fitted into the active pocket of TRPV3. Results revealed that Hypericin might be the candidates to be employed as an anti-pruritic agent in the case of psoriasis to desensitize the TRPV3 ion channel. [ABSTRACT FROM AUTHOR]

Mikania micrantha is a perennial liana of the genus Mikania of the Asteraceae family. It is a commonly used medicine in South America for treating fever, malaria, dysentery, snake bites, etc. Because of its strong adaptability and ability to inhibit the growth of its associated plants, Mikania micrantha is considered an invasive species in China and is known as a plant killer. Preliminary studies have shown that Mikania micrantha has an antipruritic effect, but the antipruritic active substance is not yet clear. In this study, a 4-aminopyridine-induced itching model in mice was used to determine the antipruritic effects of petroleum ether, ethyl acetate, ethanol extraction site, and Mikania micrantha volatile oil. GC–MS was used to analyze the components of the antipruritic fractions, combined with mice itch-causing models to study the antipruritic effects of β-caryophyllene and humulene. The safety of β-caryophyllene was preliminarily evaluated through the acute toxicity test of mice skin. The ethyl acetate and volatile oil of Mikania micrantha have apparent antipruritic effects. Humulene and β-caryophyllene have a quantitative-effective relationship to inhibit itching in mice. The acute toxicity test of mouse skin showed that β-caryophyllene has no acute toxicity. This study indicated that the main antipruritic active ingredients of Mikania micrantha are β-caryophyllene and humulene. [Display omitted] • The antipruritic active ingredient of Mikania micrantha is screened. • The new medicinal value of Mikania micrantha is obtained. • Gas chromatography-mass spectrometer is used to screen the active ingredients. • 4-aminopyridine induces itching in mice as an animal model. [ABSTRACT FROM AUTHOR]

Borneol is a long-established traditional Chinese medicine that has been found to be effective in treating pain and itchy skin. However, whether borneol has a therapeutic effect on chronic itch and its related mechanisms remain unclear. To investigate the antipruritic effect of borneol and its molecular mechanism. DrugBAN framework and molecular docking were applied to predict the targets of borneol, and the calcium imaging or patch-clamp recording analysis were used to detect the effects of borneol on TRPA1, TRPM8 or TRPV3 channels in HEK293T cells. In addition, various mouse models of acute itch and chronic itch were established to evaluate the antipruritic effects of borneol on C5 7BL /6J mice. Then, the borneol-induced pruritic relief was further investigated in Trpa1 −/− , Trpm8 −/− , or Trpa1 −/− / Trpm8 −/− mice. The effects of borneol on the activation of TRPM8 and the inhibition of TRPA1 were also measured in dorsal root ganglia neurons of wild-type (WT), Trpm8 −/− and Trpv1 −/− mice. Lastly, a randomized, double-blind study of adult patients was conducted to evaluate the clinical antipruritic effect of borneol. TRPA1, TRPV3 and TRPM8 are the potential targets of borneol according to the results of DrugBAN algorithm and molecular docking. Calcium imaging and patch-clamp recording analysis demonstrated that borneol activates TRPM8 channel-induced cell excitability and inhibits TRPA1 channel-mediated cell excitability in transfected HEK293T cells. Animal behavior analysis showed that borneol can significantly reduce acute and chronic itch behavior in C5 7BL /6J mice, but this effect was eliminated in Trpa1 −/− , Trpm8 −/− mice, or at least in Trpa1 −/− /Trpm8 −/− mice. Borneol elicits TRPM8 channel induced [Ca2+] i responses but inhibits AITC or SADBE-induced activation of TRPA1 channels in dorsal root ganglia neurons of WT and Trpv1 −/− mice, respectively. Furthermore, the clinical results indicated that borneol could reduce itching symptoms in patients and its efficacy is similar to that of menthol. Borneol has therapeutic effects on multiple pruritus models in mice and patients with chronic itch, and the mechanism may be through inhibiting TRPA1 and activating TRPM8. [Display omitted] • The clinical trial provide evidence that borneol could reduce chronic itch in patients with an efficiency similar to menthol. • The DrugBAN algorithm were applied and predicted TRPA1, TRPM8 and TRPV3 as the targets of borneol. • Borneol could relieve acute and chronic itch through inhibiting TRPA1 and activing TRPM8. [ABSTRACT FROM AUTHOR]

Guomin decoction (GMD) is a traditional Chinese medicine commonly used in clinical practice. It has traditionally been used to treat all allergic diseases. Currently, Jiawei Guomin Decoction (JWGMD) is used to treat sensitive skin after initial therapy. Although it has a significant clinical therapeutic effect, the exact role of mast cell degranulation in treating atopic dermatitis (AD) is still unclear. GMD and JWGMD can both treat allergic diseases, while JWGMD focuses on skin allergies. This study aims to explore the potential effect of JWGMD on the degranulation of mast cells in an AD mouse model induced by 2,4-dinitrofluorobenzene (DNFB) and investigate the effectiveness of JWGMD in alleviating disease progression to further provide specific therapeutic targets for treating AD. The scratching times and skin lesions of model mice induced by DNFB were observed, and skin tissues were collected for subsequent measurement. Histopathological changes in the back skin of mice were observed by haematoxylin eosin (H&E) staining, Toluidine blue staining was used to detect the degranulation of mouse skin mast cells, and the relationship between the expression of histamine (HIS), mast cell tryptase (MCT) and mast cell degranulation was analysed by enzyme-linked immunosorbent assay (ELISA). The expression of protease-activated receptor-2 (PAR-2), histamine 1 receptor (H1R), H2R, H4R and MCT proteins in AD mice was detected by Western blot (WB). Immunofluorescence assay (IFA) further confirmed the localization of PAR-2, H1R, H2R, H4R, and MCT proteins in the skin. Quantitative real-time PCR (qPCR) was used to determine PAR-2, H1R, H2R and H4R mRNA levels in skin lesions to further clarify the mechanism by which JWGMD amplifies mast cell degranulation in AD. In addition, a reliable ultrahigh-performance liquid chromatography-quadrupole electrostatic field orbitrap mass spectrometry (UPLC-QE-MS) nontargeted metabolomics analysis was performed to analyse the differences in metabolite abundance between GMD and JWGMD, and these results were used to identify the active components in JWGMD that may have antipruritic and anti-inflammatory properties and inhibit mast cell degranulation. After intermittent stimulation with DNFB, the skin lesions showed extensive desquamation, dryness, scabbing, skin thickening, and slight bleeding. Both treatments alleviated this phenomenon and reduced the number of scratches, with JWGMD being the most effective. JWGMD can significantly reduce inflammatory cell infiltration, oedema, and some capillary neogenesis in mice and reduce the degranulation of mast cells. The ELISA results showed that JWGMD can increase the levels of MCT and HIS proteins. The WB and IFA results demonstrated that JWGMD reduced the expression levels of PAR-2, H1R, H4R, and MCT proteins in skin lesions, with protein localization mainly in the epidermal layer, while H2R protein levels were increased and mainly localized in the dermis. In addition, JWGMD downregulates the mRNA expression of PAR-2, H1R, H2R, and H4R. Interestingly, through UPLC-QE-MS nontargeted metabolomic analysis, we detected the anti-inflammatory and antiallergy active substances in JWGMD, such as methyl eugenol, dictamnine and sinapine. JWGMD may alleviate itching through methyl syringol, dictamnine, sinapine and other substances, and its mechanism may be related to inhibiting the HIS/PAR-2 pathway in AD model mice and further regulating the self-amplification of mast cell degranulation. JWGMD is a potential drug for treating AD. Therefore, it deserves continuous attention and research. [Display omitted] [ABSTRACT FROM AUTHOR]

A case study of 62 year old Veteran male is presented who was to undergo abdominal panniculectomy/mastectomy. Topics include considered that based on a recent prospective report of successful intrathecal diamorphine use in bariatric surgery, and given his history of OSA, decided to administer several mg of preservative free morphine intrathecally along with three-drug antiemetic prophylaxis.

For decades, antihistamines have been the mainstay of treatment for chronic pruritus, yet they often only work by making patients drowsy and forgetful of their itch. A new era of antipruritic drugs is quickly approaching, presenting more effective treatments for patients suffering from chronic itch. Several treatments have been developed targeting specific receptors in the nervous system, such as the transient receptor potential channels, sodium channels, neurokinin-1 receptors, opioid receptors, and many more. Additionally, antipruritic therapies developed to work on the immune system have become more targeted, leading to greater safety and efficacy measures. These include crisaborole, several interleukin antagonists, and janus kinase inhibitors. The promising results presented with these new antipruritic therapies allow physicians to be better equipped to treat their itchy patients.

For decades, antihistamines have been the mainstay of treatment for chronic pruritus, yet they often only work by making patients drowsy and forgetful of their itch. A new era of antipruritic drugs is quickly approaching, presenting more effective treatments for patients suffering from chronic itch. Several treatments have been developed targeting specific receptors in the nervous system, such as the transient receptor potential channels, sodium channels, neurokinin-1 receptors, opioid receptors, and many more. Additionally, antipruritic therapies developed to work on the immune system have become more targeted, leading to greater safety and efficacy measures. These include crisaborole, several interleukin antagonists, and janus kinase inhibitors. The promising results presented with these new antipruritic therapies allow physicians to be better equipped to treat their itchy patients. [ABSTRACT FROM AUTHOR]

Copyright of Der Internist is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Nalfurafine is the first clinically approved kappa‐opioid receptor (KOP‐r) agonist as an antipruritus drug with few side effects in humans (e.g., sedation, depression, and dysphoria). No study, however, has been done using nalfurafine on alcohol drinking in rodents or humans. Methods: We investigated whether nalfurafine alone or in combination with mu‐opioid receptor (MOP‐r) antagonist naltrexone changed excessive alcohol drinking in male and female C57BL/6J (B6) mice subjected to a chronic intermittent‐access drinking paradigm (2‐bottle choice, 24‐hour access every other day) for 3 weeks. Neuronal proopiomelanocortin enhancer (nPE) knockout mice with brain‐specific deficiency of beta‐endorphin (endogenous ligand of MOP‐r) were used as a genetic control for the naltrexone effects. Results: Single administration of nalfurafine decreased alcohol intake and preference in both male and female B6 mice in a dose‐dependent manner. Pretreatment with nor‐BNI (a selective KOP‐r antagonist) blocked the nalfurafine effect on alcohol drinking, indicating a KOP‐r‐mediated mechanism. Pharmacological effects of a 5‐dosing nalfurafine regimen were further evaluated: The repeated nalfurafine administrations decreased alcohol consumption without showing any blunted effects, suggesting nalfurafine did not develop a tolerance after the multidosing regimen tested. Nalfurafine did not produce any sedation (spontaneous locomotor activity), anhedonia‐like (sucrose preference test), anxiety‐like (elevated plus maze test), or dysphoria‐like (conditioned place aversion test) behaviors, suggesting that nalfurafine had few side effects. Investigating synergistic effects between low‐dose naltrexone and nalfurafine, we found that single combinations of nalfurafine and naltrexone, at doses lower than individual effective dose, profoundly decreased excessive alcohol intake in both sexes. The effect of nalfurafine on decreasing alcohol consumption was confirmed in nPE−/− mice, suggesting independent mechanisms by which nalfurafine and naltrexone reduced alcohol drinking. Conclusion: The clinically utilized KOP‐r agonist nalfurafine in combination with low‐dose naltrexone has potential in alcoholism treatment. [ABSTRACT FROM AUTHOR]

Folic acid (FA) deficiency is associated with several health problems, including megaloblastic anemia and fetal neural tube defects. Therefore, supplementation with FA is strongly recommended by governments worldwide. Recent published reports indicate that FA functions in immune system maintenance. The main objective of this study is to examine possible anti-inflammatory and antipruritic effects of FA using a mouse model of allergic dermatitis. The mouse model was developed by repetitive sensitization to the Th2-type hapten toluene-2,4-diisocyanate (TDI). During the development of allergic dermatitis, FA was orally administered to the mice at doses of 8, 160, 1000 or 10,000 μg/day for 5 weeks. The ear swelling response and scratching behavior were monitored after the TDI challenge. Serum, ear tissue and auricular lymph node samples were isolated for further analysis 24 h after the TDI challenge. The ear swelling response was reduced in a dose-dependent manner by FA administration, and a significant change was observed at a concentration of 10,000-μg/day group. Comparable results were obtained through histological evaluation and cytokine level measurement in the ear tissue samples. Oral administration of FA exhibited the inhibitory effect on T-cell infiltration and T-cell-related cytokine production in auricular lymph nodes. Scratching behavior was not altered by FA administration. The in vivo evidence was corroborated by in vitro results, which showed that FA treatment significantly interfered with T-cell proliferation in a dose-dependent manner. Our findings imply that subacute oral administration of FA elicits an anti-inflammatory response, mainly through inhibition of T-cell proliferation. [ABSTRACT FROM AUTHOR]

The Janus kinase 1/3 inhibitor tofacitinib has demonstrated an antipruritic effect in two phase III studies in psoriasis. However, the mechanisms behind this antipruritic effect are still unknown. We presently investigated whether tofacitinib affects spontaneous itch as well as expression of itch-related cytokines and epidermal nerve fiber density (ENFD) in the imiquimod-induced mouse model of psoriasis. Psoriasis-like skin lesions were produced by daily topical application of imiquimod to the back skin. Imiquimod treatment resulted in spontaneous scratching, which was significantly inhibited by tofacitinib treatment. Imiquimod treatment significantly increased mRNA expression of Il22, Il23, and Il31, reduced peptidergic ENFD, and increased nonpeptidergic ENFD compared to naive mice. Tofacitinib significantly decreased the expression of those cytokines and increased peptidergic ENFD without a significant effect on nonpeptidergic ENFD. Tofacitinib may inhibit psoriatic itch through inhibition of cytokine expression as well as modulation of epidermal innervation. [ABSTRACT FROM AUTHOR]

Objective: Sophorae Flavescentis Radix (Kuh-seng, SFR), a Traditional Chinese Medicine (TCM), is widely used alone or within a TCM formula to treat pruritus, especially histamine-independent intractable itching. In the previous study, potential antipruritic active components of the SFR were screened based on cell membrane immobilized chromatography (CMIC), revealing oxymatrine (OMT) as an antipruritic agent. However, the low oral bioavailability (OB) of OMT cannot explain the antipruritic effect of SFR when administered orally in clinic. In this study, we investigated the antipruritic effects and underlying mechanisms of orally administered SFR., Materials and Methods: A network pharmacology and molecular docking were employed to screen the active components of SFR and predict their binding to disease-related target proteins, while the potential mechanisms were explored with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. The binding energy between components and target proteins was calculated by molecular docking., Results: The SFR-components-targets-intractable itching Protein-Protein Interactions (PPI) network was established, and 22 active components and 42 targets were screened. The GO enrichment analysis showed that the key target genes of SFR were related to nuclear receptors, transcription factors, and steroid hormone receptors. The results of the KEGG enrichment pathway analysis include Hepatitis B, epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor resistance, advanced glycation end product (AGE)-receptor for AGE (RAGE) signaling pathway in diabetic complications, etc. Molecular docking showed that three key target proteins in the network, the vascular endothelial growth factor A (VEGFA), epidermal growth factor receptor (EGFR) and caspase-3 (CASP3), have higher binding activities with inermine, phaseolin and kushenol O, respectively; the binding energy of each pair is stronger than that of the target protein-corresponding inhibitors., Conclusions: The complexity of the SFR-components-targets-intractable itching network demonstrated the holistic treatment effect of SFR on intractable itching. The partial coherence between results screened by CMIC in the previous study and network pharmacology demonstrated the potential of network pharmacology in active component screening. Inermine screened from both CMIC and network pharmacology is a VEGFA inhibitor, which possibly accounts for the antipruritic effect of orally administered SFR.

Abstract This study aimed to evaluate the role of NecroX-5, a powerful anti-inflammatory agent, on the functional plasticity of macrophages and the possible underlying mechanism using RAW264.7 cells, thioglycollate-elicited peritoneal macrophages from C57BL/6 mice, and a murine model of dextran sodium sulfate (DSS)-induced colitis. The change in cell morphology was examined by scanning electron microscopy. The expression of CD206, arginase (Arg)-1, and inducible nitric oxide synthase (iNOS) were examined by western blotting. The production of inflammatory cytokines was detected by enzyme-linked immunosorbent assays and statistical comparisons were made. The results showed that treatment of RAW264.7 cells with NecroX-5 caused an elongated shape in comparison to non-treated cells. The expression levels of macrophage mannose receptor CD206 and Arg-1, specific markers of M2 cells, were significantly upregulated by NecroX-5 treatment, while those of iNOS (M1 macrophages) was decreased. In addition, NecroX-5 significantly reduced the secretion of inflammatory cytokines, while interleukin (IL)-4 and IL-13 secretion in the supernatant was significantly enhanced. Treatment with NecroX-5 considerably ameliorated the progression of DSS-induced colitis and significantly inhibited the mRNA expression of pro-inflammatory cytokines, including tumor necrosis factor-α and IL-1β. Taken together, our findings demonstrated that NecroX-5 might dampen inflammation by switching the M1 phenotype to the M2 phenotype due to IL-4 and IL-13 induction. Graphical abstract Unlabelled Image Highlights • NecroX-5 caused an elongated shape of RAW264.7 cells stimulated with LPS. • NecroX-5 increased the mRNA expression of CD206 and Arg-1. • NecroX-5 decreased the expression of iNOS, specific marker of M1 cells. • NecroX-5 reduced the secretion of TNF-α, IL-1β, and IL-6. • NecroX-5 ameliorated DSS-induced colitis. [ABSTRACT FROM AUTHOR]

Nurses may see patients who have recently returned from tropical vacations complaining of a severe pruritic dermatitis known as seabather's eruption (SBE). Caused by exposure to jellyfish larvae, SBE is characterized by a pruritic rash, but some patients, particularly children, experience systemic signs and symptoms such as fever, chills, and nausea/vomiting. This article discusses SBE and reviews assessment tips, nursing care, and patient teaching. [ABSTRACT FROM AUTHOR]

Copyright of Boletín Latinoamericano y del Caribe de Plantas Medicinales y Aromáticas is the property of Universidad de Santiago de Chile and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The pharmaceutical combination of dexpanthenol (DPA), lidocaine hydrochloride (LIH) and mepyramine maleate (MAM) is used for their anti-allergic, anti-inflammatory, anti-pruritic, anesthetic and antiseptic properties. The present study was aimed to develop and validate a new, first and rapid high performance liquid chromatographic method for simultaneous determination of DPA, LIH and MAM in the presence of their stress-induced degradation products in pharmaceutical gel/fluigel formulations. The chromatographic separation was performed on an Inertsil ODS-3 V, 250 × 4.6 mm (5 μm) column using a gradient mobile phase of an aqueous solution of ammonium acetate (0.01 M) and methanol mixture at gradient flow rates of 1.3 mL/min and 1.5 mL/min with detection at 230 nm. The retention times for DPA, LIH and MAM were ~3.28 min, 11.67 min and 12.99 min, respectively. The method was validated in accordance with International Conference on Harmonisation guidelines. Calibration curves were linear in the ranges of 9–54 μg/mL for MAM and LIH and 30–180 μg/mL for DPA with satisfactory correlation coefficients (R 2> 0.999). The mean % recoveries obtained were found to be 99.9% for MAM, 100.3% for LIH and 99.3% for DPA. Precision % RSD was <2. Robustness results were uniform, there were no marked changes, so method is highly validated. All drugs were subjected to stress conditions and degradation products were separated with acceptable peak tailing (T ≤ 2) and good resolution (R s> 2). The validated method therefore can be adapted for quality control procedures of the drugs in pharmaceutical dosage forms and their stability studies. [ABSTRACT FROM AUTHOR]

The TRPA1 and TRPV1 receptors are important pharmaceutical targets for antipruritic and analgesic therapy. Obtaining further knowledge on their roles and interrelationship in humans is therefore crucial. Preclinical results are contradictory concerning coexpression and functional interdependency of TRPV1 and TRPA1, but no human evidence exists. This human experimental study investigated whether functional responses from the subpopulation of TRPA1 nociceptors could be evoked after defunctionalization of TRPV1 nociceptors by cutaneous application of high-concentration capsaicin. Two quadratic areas on each forearm were randomized to pretreatment with an 8% topical capsaicin patch or vehicle for 24 hours. Subsequently, areas were provoked by transdermal 1% topical capsaicin (TRPV1 agonist) or 10% topical allyl isothiocyanate ("AITC," a TRPA1 agonist), delivered by 12 mm Finn chambers. Evoked pain intensities were recorded during pretreatments and chemical provocations. Quantitative sensory tests were performed before and after provocations to assess changes of heat pain sensitivity. Imaging of vasomotor responses was used to assess neurogenic inflammation after the chemical provocations. In the capsaicin-pretreated areas, both the subsequent 1% capsaicin- and 10% AITC-provoked pain was inhibited by 92.9 ± 2.5% and 86.9 ± 5.0% (both: P < 0.001), respectively. The capsaicin-ablated skin areas showed significant heat hypoalgesia at baseline (P < 0.001) as well as heat antihyperalgesia, and inhibition of neurogenic inflammation evoked by both 1% capsaicin and 10% AITC provocations (both: P < 0.001). Ablation of cutaneous capsaicin-sensitive afferents caused consistent and equal inhibition of both TRPV1- and TRPA1-provoked responses assessed psychophysically and by imaging of vasomotor responses. This study suggests that TRPA1 nociceptive responses in human skin strongly depend on intact capsaicin-sensitive, TRPV1 fibers. [ABSTRACT FROM AUTHOR]

Itching is a common clinical symptom of skin disease that significantly affects a patient's quality of life. Transient receptor potential vanilloid 1 (TRPV1) receptors of keratinocytes and peripheral nerve fibers in skin are involved in the regulation of itching as well as pain. In this study, we investigated whether curcumin, which acts on TRPV1 receptors, affects histamine-induced itching in mice, using behavioral tests and electrophysiological approaches. We found that histamine-induced itching was blocked by topical application of curcumin in a concentration-dependent manner. In ex-vivo recordings, histamine-induced discharges of peripheral nerves were reduced by the application of curcumin, indicating that curcumin acts directly on peripheral nerves. Additionally, curcumin blocked the histamine-induced inward current via activation of TRPV1 (curcumin IC50=523 nM). However, it did not alter chloroquine-induced itching behavior in mice, which is associated with transient receptor potential ankyrin 1 (TRPA1). Taken together, our results suggest that histamine-induced itching can be blocked by topical application of curcumin through the inhibitory action of curcumin on TRPV1 receptors in peripheral nerves. [ABSTRACT FROM AUTHOR]

The antipruritic activity of gabapentin, an anticonvulsant, was studied in a mouse model of allergic itch. In mice sensitized by an extract of the salivary glands of the mosquito (ESGM), an intradermal injection of ESGM elicited scratching and increased peripheral nerve firing. Oral or intradermal administration of gabapentin at the ESGM injection site inhibited ESGM-induced scratching and peripheral nerve firing. However, gabapentin did not affect histamine-induced scratching. The distributions of immunoreactivity to the voltage-dependent calcium channel α 2 δ-1 subunit, a site of gabapentin action, and the histamine H 1 receptor differed in the mouse dorsal root ganglia. The α 2 δ-1 subunit was mainly found in neurons that were 15–20 µm in diameter, whereas the H 1 receptor was mainly in 20–30 µm neurons. In addition, α 2 δ-1 subunit immunoreactivity co-localized with that of transient receptor potential vanilloid 1 (TRPV1). These results suggest that gabapentin regulates allergic itch by acting on the calcium channel α 2 δ-1 subunit in peripheral TRPV1-positive neurons. [ABSTRACT FROM AUTHOR]

Summary: Background: Cannabinoids have been used for their analgesic and euphoric effects for millennia, but recently the antipruritic effects of cannabis have been discovered. Considering the similarities between pain and itch sensations, we hypothesized that cannabinoid receptors may play a role in the antipruritic effects of cannabinoids. Aim: To analyse the role of the spinal cannabinoid receptors, CB1 and CB2, in the antipruritic effects of the cannabinoid agonist WIN 55,212‐2. Methods: Male Balb/c mice weighing 20–30 g were used. Scratching behaviour in the mice was produced by injection of serotonin 5 μg/50 μL intradermally into the nape of the neck. Scratching of the site of injection by the hind paws was video‐recorded for 30 min. After testing different doses of WIN 55,212‐2 [1, 3 and 10 mg/kg intraperitoneally (IP)], the effects of the CB1 receptor antagonist, AM‐251 [1 μg/mouse administered intrathecally (IT)] and the CB2 receptor antagonist AM‐630 (4 μg/mouse IT) on the antipruritic effects of WIN 55,212‐2 were studied using a rotarod apparatus. Results: WIN 55,212‐2 (1, 3 or 10 mg/kg IP) dose‐dependently decreased serotonin‐induced scratches. The receptor antagonist CB1 partially reversed the effects of WIN 55,212‐2 (P < 0.05); whereas CB2 had no statistically significant effect. WIN 55,212‐2 impaired motor function only at the highest dose given (10 mg/kg, P < 0.05). Conclusions: Our findings support prior researches indicating that cannabinoids exert antipruritic effects. Moreover, our results show that the antipruritic effects of cannabinoids are partially mediated by spinal CB1 receptors. [ABSTRACT FROM AUTHOR]

The main clinical manifestations of eczema include itching, erythema, swelling and pain. Currently, allergies and TH1/TH2 cytokine imbalances are significant causes of eczema. TCM believes that eczema is mainly caused by incongruity between dry and wet. Wenguanmu ointment is a classic Mongolian medicine, which mainly composed of Xanthoceras sorbifolia Bunge , Coptis chinensis Franch and Bezoar. These ingredients can clear heat and dampness, dispel wind and dehumidification, anti-inflammatoryad analgesic. In this study, it was found that Wenguanmu ointment can treat eczema with anti-inflammatory, analgesic and antipruritic. In this study, the content of main components in Wenguanmu ointment was tested. Moreover, the therapeutic effect and mechanism of Wenguanmu ointment on eczema model mice were studied. Kunming mice (25 ± 2 g) were randomly divided into 6 groups: Control group; Model group; Vehicle group; Wenguanmu ointment group; Compound dexamethasone acetate cream group; Chushizhiyang ointment group. The eczema mouse model was established by DNCB. HPLC and TLC tests were used to determine the content of the main components in Wenguanmu ointment. HE staining was used to assess skin damage in mice. In order to detect the anti-inflammatory effect of Wenguanmu ointment on eczema, The levels of IgE, TNF-α, IFN-γ, COX-2 and IL-4 in serum was measured by ELISA. Genecards and Online Mendelian Inheritance in Man databases were used to analyze potential target gene predictions, and it was speculated that Wenguanmu ointment was associated with NF−κB signaling pathway and chemokine signaling pathway. To detect this inference, RT-qPCR and western blotting were used to detect protein and mRNA levels of CKLF-1, IκB-α, and NF-κB. Wenguanmu ointment can repress the symptoms of eczema caused by 2, 4-dinitrochlorobenzene, and inhibit the level of serum immunoglobulin E. Simultaneously it restrain the elevation of miscellaneous pro-inflammatory cytokines and chemokines, as well as reducing the expression of CKLF-1 and NF-κB protein in the nucleus, and increasing the protein expression of IκB to improve eczema. The ameliorating effect of Wenguanmu ointment on eczema lesions can play a importment role by inhibiting the CKLF-1/NF-κB pathway. [Display omitted] [ABSTRACT FROM AUTHOR]

Phototoxicity-induced pain is a major clinical problem triggered by light acting on photosensitising drugs or endogenous porphyrins, notably protoporphyrin IX (PpIX), an intermediary in heme biosynthesis. Protoporphyrin IX accumulates in individuals with erythropoietic protoporphyria and is elevated during photodynamic therapy subsequent to application of 5-aminolevulinic acid (ALA). Pain occurs during irradiation of PpIX and responds poorly to conventional analgesics. Our objective was to develop a model of PpIX phototoxicity pain and investigate the potential of menthol as an analgesic. Application of ALA to the tails of C57 black and SWISS white mice caused PpIX accumulation and nociception during irradiation (630 nm at 3.7 J/cm). Despite similar PpIX accumulation, C57 mice exhibited less pain behavior compared with SWISS mice because of light absorption by pigmentation. Irradiation of ALA-treated dorsal root ganglion neurons caused phototoxicity-evoked action potentials (APs) in both mouse strains. The antioxidant L-tryptophan increased the light dose required to elicit such APs. By contrast, the addition of keratinocytes to neuronal cultures decreased the threshold for APs, suggesting a requirement for proliferating cells. Inhibition of fatty acid amide hydrolase, selective antagonism of TRPV1 or the application of lidocaine or its quaternary derivative QX-314, reduced AP frequency, whereas antagonism of TRPA1 had no effect. These results suggest that products of singlet oxygen-mediated lipid peroxidation trigger nociceptor activation via TRPV1. Menthol inhibited phototoxicity-evoked APs and reduced pain behavior when applied topically to mice. These findings suggest that menthol might provide pain relief in patients experiencing PpIX-phototoxicity pain caused by photodynamic therapy or erythropoietic protoporphyria. [ABSTRACT FROM AUTHOR]