CGRP inhibits proliferation, activation and cytokine secretion of group 2 innate lymphoid cells (ILC2) in peripheral blood from patients with allergic rhinitis / 细胞与分子免疫学杂志

Objective To investigate the effect of calcitonin gene-related peptide (CGRP) on the regulation of group 2 innate lymphoid cells (ILC2) in the peripheral blood of patients with allergic rhinitis (AR). Methods Peripheral blood mononuclear cells (PBMCs) were extracted from normal healthy individuals and AR patients, then stimulated with CGRP, interleukin 33 (IL-33) and CGRP combined with IL-33 for 3 days, with blank stimulus as control. The percentage of ILC2 in the four groups was measured by flow cytometry. After being sorted, ILC2 was given to CGRP, IL-33 and CGRP combined with IL-33 stimulation for 3 days, with blank stimulus as control. The percentage of IL-5 and IL-13 positive cells in ILC2 was detected by flow cytometry, and the levels of IL-5 and IL-13 in ILC2 supernatant were measured by ELISA. Results The percentage of ILC2 in the peripheral blood of AR patients was significantly higher than that of the control group. The levels of IL-5+ILC2 and IL-13+ILC2 were significantly increased by IL-33 single stimulation after culturing PBMCs. After adding IL-33 combined with CGRP stimulation, the levels of IL-5+ILC2 and IL-13+ILC2 in PBMCs were significantly reduced; after CGRP single stimulation, the levels of IL-5+ILC2 and IL-13+ILC2 in PBMCs were further decreased. After ILC2 was sorted and cultured, the levels of IL-5+ILC2 and IL-13+ILC2 showed significant increase after IL-33 single stimulation. The levels of IL-5+ILC2 and IL-13+ILC2 were decreased by IL-33 and CGRP co-stimulation, and they were further reduced after CGRP single stimulation. Compared to IL-33 single stimulation, IL-5 and IL-13 levels dropped significantly due to the IL-33 and CGRP co-stimulation. The levels of IL-5 and IL-13 were further reduced by CGRP single stimulation. Conclusion CGRP inhibits the proliferation and activation of peripheral blood ILC2 in AR and exert anti-inflammatory effects in AR.

Protective effect of Liujing Toutong Tablets on rats with permanent cerebral ischemia via NF-κB signaling pathway / 中国中药杂志

This study investigated the neuroprotective effects and underlying mechanism of Liujing Toutong Tablets(LJTT) on a rat model of permanent middle cerebral artery occlusion(pMCAO). The pMCAO model was established using the suture method. Eighty-four male SPF-grade SD rats were randomly divided into a sham operation group, a model group, a nimodipine group(0.020 g·kg~(-1)), and high-, medium-, and low-dose LJTT groups(2.8, 1.4, and 0.7 g·kg~(-1)). The Longa score, adhesive removal test and laser speckle contrast imaging technique were used to evaluate the degree of neurological functional impairment and changes in local cerebral blood flow. The survival and mortality of rats in each group were recorded daily. After seven days of continuous administration following the model induction, the rats in each group were euthanized, and brain tissue and blood samples were collected for corresponding parameter measurements. Nissl staining was used to examine pathological changes in brain tissue neurons. The levels of tumor necrosis factor-alpha(TNF-α), interleukin-6(IL-6), IL-1β, vascular endothelial growth factor(VEGF), calcitonin gene-related peptide(CGRP), beta-endorphin(β-EP), and endogenous nitric oxide(NO) in rat serum were measured using specific assay kits. The entropy weight method was used to analyze the weights of various indicators. The protein expression levels of nuclear factor kappa-B(NF-κB), inhibitor kappaB alpha(IκBα), phosphorylated IκBα(p-IκBα), and phosphorylated inhibitor of NF-κB kinase alpha(p-IKKα) in brain tissue were determined using Western blot. Immunohistochemistry was used to detect the protein expression of chemokine-like factor 1(CKLF1) and C-C chemokine receptor 5(CCR5) in rat brain tissue. Compared with the sham operation group, the model group showed significantly higher neurological functional impairment scores, prolonged adhesive removal time, decreased cerebral blood flow, increased neuronal damage, reduced survival rate, significantly increased levels of TNF-α, IL-1β, IL-6, CGRP, and NO in serum, significantly decreased levels of VEGF and β-EP, significantly increased expression levels of NF-κB p65, p-IκBα/IκBα, and p-IKKα in rat brain tissue, and significantly upregulated protein expression of CKLF1 and CCR5. Compared with the model group, the high-dose LJTT group significantly improved the neurological functional score of pMCAO rats after oral administration for 7 days. LJTT at all doses significantly reduced adhesive removal time and restored cerebral blood flow. The high-and medium-dose LJTT groups significantly improved neuronal damage. The LJTT groups at all doses showed reduced levels of TNF-α, IL-1β, IL-6, CGRP, and NO in rat serum, increased VEGF and β-EP levels, and significantly decreased expression levels of NF-κB p65, p-IκBα/IκBα, p-IKKα, and CCR5 protein in rat brain tissue. The entropy weight analysis revealed that CGRP and β-EP were significantly affected during the model induction, and LJTT exhibited a strong effect in reducing the release of inflammatory factors such as TNF-α and IL-1β. LJTT may exert a neuroprotective effect on rats with permanent cerebral ischemia by reducing neuroinflammatory damage, and its mechanism may be related to the inhibition of the NF-κB signaling pathway and the regulation of the CKLF1/CCR5 axis. Additionally, LJTT may exert certain analgesic effects by reducing CGRP and NO levels and increasing β-EP levels.

Effects of iontophoretically applied substance P, calcitonin gene-related peptide on excitability of dorsal horn neurones in rats

Spontaneous pain, allodynia and hyperalgesia are well known phenomena following peripheral nerve or tissue injury, and it is speculated that secondary hyperalgesia and allodynia, are generally thought to depend on a hyperexcitability (sensitization) of neurons in the dorsal horn. It is supposed that the sensitization may be due to various actions of neurotransmitters (SP, CGRP, excitatory amino acids) released from the primary afferent fibers. In this study, we examined effects of the iontophoretically applied SP and CGRP on the response to EAA receptor agonists (NMDA and non-NMDA) in the WDR dorsal horn neurones and see if the effects of SP or CGRP mimic the characteristic response pattern known in various pain models. The main results are summarized as follows: 1) SP specifically potentiated NMDA response. 2) CGRP non-specifically potentiated both NMDA and AMPA responses. Potentiation of NMDA response, however, was significantly greater than that of AMPA response. 3) 50% of SP applied cells and 15.8% of CGRP applied cells showed reciprocal changes(potentiation of NMDA response and suppression of AMPA response). These results are generally consistent with the sensitization characteristics in diverse pain models and suggests that the modulatory effects of SP and CGRP on NMDA and non-NMDA (AMPA) response are, at least in part, contribute to the development of sensitization in various pain models.