Role of stromal interaction molecule 2 in chronic itch

基质相互作用分子2在慢性瘙痒中的作用

• 批准号: 10660144
• 负责人: Huijuan Hu
• 金额: $ 41.14万
• 依托单位: RUTGERS BIOMEDICAL AND HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-02-15 至 2028-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10660144
• 关键词: Ablation; Acute; Aftercare; Antibodies; Astrocytes; Attenuated; Behavior; Calcium; Calcium Channel; Chloroquine; Clinical; Couples; Cytomegalovirus; Data; Dinitrobenzenes; Dinitrofluorobenzene; Dryness; Endoplasmic Reticulum; Family member; Fluorescein-5-isothiocyanate; GRP gene; Genetic; Glial Fibrillary Acidic Protein; Histamine; Interleukin-1 beta; Interleukin-6; Knock-out; Knockout Mice; LCN2 gene; Measures; Mediating; Mediator; Messenger RNA; Microinjections; Molecular; Mus; Neurons; Nociception; Pain; Pathway interactions; Pattern; Play; Posterior Horn Cells; Production; Proteins; Pruritus; Research; Role; STIM1 gene; Signal Pathway; Signal Transduction; Skin; Slice; Spinal; Spinal Cord; Stains; Stat3 protein; TLR4 gene; TNF gene; Testing; Time; Touch sensation; Vertebral column; Western Blotting; Work; antagonist; cell type; chronic itch; conditional knockout; cytokine; dorsal horn; excitatory neuron; hindbrain; insight; knock-down; mouse model; neuronal excitability; novel; overexpression; response; sensor; transmission process; vesicular glutamate transporter 2

Abstract Chronic itch is a debilitating condition and represents a clinical challenge. Increase evidence has demonstrated that neuronal and astrocytic signaling pathways in the spinal cord play a crucial role in chronic itch. Although several molecules have been identified as key itch mediators/modulators, molecular mechanisms underlying chronic itch remain incompletely understood. Our research has been focused on role of store-operated calcium channels (SOCs) in pain and itch. We have shown that the primary SOC family members STIM1 and STIM2 (endoplasmic reticulum Ca2+ sensors) are expressed in dorsal horn neurons and astrocytes, but their functional significance in the spinal cord is still elusive. We recently generated vesicular glutamate transporters 2 (Vglut2, an excitatory neuron marker) conditional STIM1 and STIM2 knockout (KO) mice. Our pilot data showed that deletion of STIM1 in Vglut2+ neurons attenuated nociception, but did not affect pruritogen-induced scratches. In contrast, ablation of STIM2 in Vglut2+ neurons (v-STIM2 KO) markedly attenuated pruritogen-induced scratches, but had no effect on nociception. These exciting pilot work suggests that STIM1 and STIM2 play distinct roles in pain and itch. Our pilot data also show that inhibition of STIMs by intrathecal, not intradermal injection, decreased histamine (His)- and chloroquine (CQ)-induced itch behavior. Moreover, inhibition or deletion of excitatory neuronal STIM2 attenuated FITC- and DNFB-induced chronic itch, suggesting that neuronal STIM2 play a role in both acute and chronic itch. Importantly, STIM2 expression was increased in the dorsal horn from diphenylcyclopropenone (DCP)- and 1-fluoro-2, 4-dinitrobenzene (DNFB)-induced mouse models of chronic itch. GRPR plays a critical role in itch transmission. Our pilot data showed that deletion of STIM2 in Vglut2 or Lbx1 (specifically expressed in spinal and hindbrain neurons)-expressing neurons drastically attenuated GRP-induced Ca2+ responses and itch behavior. It is known that signal transducer and activator of transcription 3 (STAT3) and its downstream lipocalin-2 (LCN2) are key modulators of chronic itch. We found that activation of TLR4 upregulated STIM2 expression via STAT3 signaling. Based on these findings, we hypothesize that spinal STIM2 plays a crucial role in chronic itch through a combination of neuronal and astrocytic signaling pathways. In Aim 1, we will determine whether ablation or knockdown of spinal STIM2 attenuates chronic itch. In Aim 2, we will examine the expression and function of STIM2 under chronic itch conditions. In Aim 3, we will investigate the mechanisms underlying spinal STIM2 involvement in chronic itch. The proposed work will establish a novel role of STIM2 in itch sensation and will provide new insights into the mechanisms of GRPR in itch transmission. Successful completion of this research will not only identify STIM2 as a key modulator in chronic itch, but also decipher the cellular and molecular mechanisms underlying chronic itch.

抽象的 慢性瘙痒是一种令人衰弱的状况，代表了临床挑战。增加证据已证明 脊髓中的神经元和星形胶质细胞信号通路在慢性瘙痒中起着至关重要的作用。虽然 几个分子已被确定为关键瘙痒介质/调节剂，分子机制 慢性瘙痒仍然不完全理解。我们的研究集中在商店经营的钙的作用上 痛苦和瘙痒的频道（SOC）。我们已经表明，主要的SoC家族成员Stim1和Stim2 （内质网Ca2+传感器）在背角神经元和星形胶质细胞中表达，但其功能性 脊髓中的重要性仍然难以捉摸。我们最近生成了囊泡谷氨酸转运蛋白2（vglut2， 一种兴奋性神经元标记）条件刺激和STIM2敲除（KO）小鼠。我们的飞行员数据表明 vglut2+神经元中STIM1的缺失减弱了伤害感受，但不会影响瘙痒诱导的划痕。在 对比，vglut2+神经元（V-STIM2 KO）中imt2的消融显着减弱了瘙痒诱导的划痕， 但对伤害感受没有影响。这些令人兴奋的飞行员工作表明，imp1和stim2在 疼痛和瘙痒。我们的飞行员数据还表明，通过鞘内抑制刺激，而不是皮内注射，降低了 组胺（HIS）和氯喹（CQ）引起的瘙痒行为。此外，抑制或删除兴奋性 神经元STIM2减弱了FITC和DNFB诱导的慢性瘙痒，表明神经元刺激起作用 在急性和慢性瘙痒中。重要的是，从背角中提高了STIM2的表达 二苯基丙酮酮（DCP） - 和1-氟-2，4-二硝基苯（DNFB）诱导的慢性瘙痒小鼠模型。 GRPR在瘙痒传输中起着至关重要的作用。我们的试点数据表明，vglut2或lbx1中的stim2删除 （特别表达在脊柱和后脑神经元）表达神经元的GRP诱导的神经元 CA2+反应和瘙痒行为。众所周知，转录3（STAT3）和 它的下游脂肪蛋白2（LCN2）是慢性瘙痒的关键调节剂。我们发现TLR4的激活 通过STAT3信号传导上调STIM2表达。基于这些发现，我们假设脊柱STIM2 通过神经元和星形胶质细胞信号通路的结合，在慢性瘙痒中起着至关重要的作用。目标 1，我们将确定脊柱刺激的消融或敲低是减弱慢性瘙痒。在AIM 2中，我们将 在慢性瘙痒条件下检查Stim2的表达和功能。在AIM 3中，我们将调查 脊柱STIM2涉及慢性瘙痒的机制。拟议的工作将确立一个新颖的角色 ITCH感觉中的STIM2，并将提供有关瘙痒传播中GRPR机制的新见解。 这项研究的成功完成不仅将识别stim2是慢性瘙痒中的关键调节剂，而且还将 破译慢性瘙痒的基础的细胞和分子机制。