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Background and Purpose: Atopic dermatitis is a common chronic pruritic inflammatory disease of the skin involving neuro‐immune communication. Neuronal mechanism‐based therapeutic treatments remain lacking. We investigated the efficacy of intravenous lidocaine therapy on atopic dermatitis and the underlying neuro‐immune mechanism. Experimental Approach: Pharmacological intervention, immunofluorescence, RNA‐sequencing, genetic modification and immunoassay were performed to dissect the neuro‐immune basis of itch and inflammation in atopic dermatitis‐like mouse model and in patients. Key Results: Lidocaine alleviated skin lesions and itch in both atopic dermatitis patients and calcipotriol (MC903)‐induced atopic dermatitis model by blocking subpopulation of sensory neurons. QX‐314, a charged NaV blocker that enters through pathologically activated large‐pore ion channels and selectivity inhibits a subpopulation of sensory neurons, has the same effects as lidocaine in atopic dermatitis model. Genetic silencing NaV1.8‐expressing sensory neurons was sufficient to restrict cutaneous inflammation and itch in the atopic dermatitis model. However, pharmacological blockade of TRPV1‐positive nociceptors only abolished persistent itch but did not affect skin inflammation in the atopic dermatitis model, indicating a difference between sensory neuronal modulation of skin inflammation and itch. Inhibition of activity‐dependent release of calcitonin gene‐related peptide (CGRP) from sensory neurons by lidocaine largely accounts for the therapeutic effect of lidocaine in the atopic dermatitis model. Conclusion and Implications: NaV1.8+ sensory neurons play a critical role in pathogenesis of atopic dermatitis and lidocaine is a potential anti‐inflammatory and anti‐pruritic agent for atopic dermatitis. A dissociable difference for sensory neuronal modulation of skin inflammation and itch contributes to further understanding of pathogenesis in atopic dermatitis. [ABSTRACT FROM AUTHOR]

Acidosis is a hallmark of ischemic stroke and a promising neuroprotective target for preventing neuronal injury. Previously, genetic manipulations showed that blockade of acid-sensing ion channel 1a (ASIC1a)-mediated acidotoxicity could dramatically alleviate the volume of brain infarct and restore neurological function after cerebral ischemia. However, few pharmacological candidates have been identified to exhibit efficacy on ischemic stroke through inhibition of ASIC1a. In this work, we examined the ability of a toxin-inspired compound 5b (C5b), previously found to effectively inhibit ASIC1a in vitro , to exert protective effects in animal models of ischemic stroke in vivo. We found that C5b exerts significant neuroprotective effects not only in acid-induced neuronal death in vitro but also ischemic brain injury in vivo , suggesting that ASIC1a is a druggable target for therapeutic development. More importantly, C5b is able to cross the blood brain barrier and significantly reduce brain infarct volume when administered intravenously in the ischemic animal model, highlighting its systemic availability for therapies against neurodegeneration due to acidotoxicity. Together, our data demonstrate that C5b is a promising lead compound for neuroprotection through inhibiting ASIC1a, which warrants further translational studies. [ABSTRACT FROM AUTHOR]

Abstract: Long chain polyunsaturated fatty acids (LC-PUFA), ARA (arachidonic acid, 20:4n −6) and DHA (docosahexaenoic acid, 22:6n −3) have positive effects and environment pollutants, polychlorinated dibenzo-p-dioxins/dibenzofurans(PCDD/F) and polychlorinated biphenyls (PCB) have negative effects on neural development during early life. Placental dioxin/PCB serves as markers for cumulative exposure to fetus. Fatty acid composition of placenta depends on nutrient supply during pregnancy, serving as indicators for fetal ARA and DHA accretion. This study investigated correlation between placental PCDD/F and PCB toxic equivalent (TEQ) and LC-PUFA in 34 pregnant women from Taiwan. Placental PCDF TEQ were inversely correlated with placental ARA (p =0.020), C20:3n −6 (p =0.01), C22:4n −6 (p =0.04), C22:5n −6 (p <0.01) and with DHA (p =0.03), but ARA and DHA did not vary with PCDD, dioxin-like and indicator PCB. After adjustment for age and body mass index, a one-unit PCDF TEQ increase was associated with 1.021%w/w and 0.312%w/w decreases in ARA (β =−1.021, p =0.03) and DHA (β =−0.312, p =0.03). Since ARA and DHA were unrelated to three classes of toxins, and a weak negative association was found with PCDF, these data provide no basis for discouraging marine fish consumption during pregnancy for Taiwan women on the basis of these organics. Pregnant women should consume fish for its unique package of nutrients while avoiding few species with high organic pollutant or mercury contamination. [Copyright &y& Elsevier]