Molecular mechanisms of glycosylation of Cav3.2 channels in pain pathway

疼痛通路中Cav3.2通道糖基化的分子机制

基本信息

批准号：
9127411
负责人：
Vesna Jevtovic-Todorovic
金额：
$ 34.59万
依托单位：
UNIVERSITY OF COLORADO DENVER
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-06-01 至 2021-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9127411
关键词：
Adverse effects Afferent Neurons Animal Model Animals Asparagine Ataxia Axon Burn injury Calcium Channel Capsaicin Cells Characteristics Chronic Chronic Disease Clinical Complication Constipation Cream Data Development Diabetes Mellitus Diabetic Neuralgia Diabetic Neuropathies Diabetic mouse Disease Dizziness Drug abuse Electrophysiology (science)Esthesia Euphoria Functional disorder Genetic Human Hyperalgesia Hyperglycemia In Vitro Intractable Pain Kinetics Knowledge Lead Leptin Lidocaine Measures Mechanics Membrane Modality Modeling Molecular Morbid Obesity Mus Nerve Neuraminidase inhibitor Neurons Nociception Nociceptors Non-Insulin-Dependent Diabetes Mellitus Numbness Obese Mice Opioid Optical Methods Outcome Pain Pain management Pathogenesis Pathway interactions Patients Peripheral Peripheral Nerves Pharmaceutical Preparations Phenotype Play Post-Translational Protein Processing Posterior Horn Cells Preparation Protein Conformation Protein Isoforms Proteins Public Health Quality of life Recombinants Regulation Regulatory Pathway Reporting Research Role Sedation procedure Site Skin Spinal Ganglia Stimulus Streptozocin Symptoms T-Type Calcium Channels Testing Therapeutic Tissues Topical application Urinary Retention Ventilatory Depression Weight Gain Wild Type Mouse Work addiction allodynia biophysical techniques cognitive function density diabetic diabetic patient diabetic rat disabling symptom effective therapy experience extracellular gabapentin ganglion cell glycosylation human disease in vivo innovation mouse model neuronal cell body new therapeutic target nociceptive response novel novel therapeutics pain symptom painful neuropathy patch clamp pregabalin protein transport public health relevance response sugar tool transmission process type I and type II diabetes voltage

项目摘要

DESCRIPTION (provided by applicant): Pain-sensing sensory neurons of the dorsal root ganglion (DRG) can become sensitized (hyperexcitable) in response to pathological conditions such as diabetes. Due to insufficient knowledge concerning the mechanisms underlying this sensitization, current treatments for painful diabetic neuropathy are limited to somewhat non-specific systemic drugs, such as opioids or gabapentin, which can cause significant side effects and have high potential for abuse. Recent studies have established that T-channels make a previously unrecognized contribution to sensitization of pain responses by enhancing excitability of nociceptors. We recently showed that DRG T-currents are up-regulated in streptozotocin (STZ)-induced and ob/ob mouse models of diabetic neuropathy and contribute to enhanced pain transmission. In preliminary data, we show that the glycosylation inhibitor neuraminidase inhibits T-currents and reverses thermal and mechanical hyperalgesia in these animal models. This finding has led us to hypothesize that post-translational glycosylation of the CaV3.2 channel increases activity, enhances excitability of nociceptive DRG neurons, and consequently contributes to the symptoms of painful diabetic neuropathy. Our specific aims are to: Aim 1: To use patch-clamp recordings and biophysical methods to study glycosylation-induced alterations of CaV3.2 T-channel activity in acutely dissociated DRG neurons in vitro. We propose that alterations in T-current kinetics and density can directly influence excitability of nociceptive DR cells. Aim 2: To investigate sites at which glycosylation of CaV3.2 T-channels occur in recombinant cells, native, and cultured DRG neurons. We propose that glycosylation of specific extracellular asparagine residues of CaV3.2 channels increases current density and membrane expression of the channel. Aim 3: To test the hypothesis that glycosylation of CaV3.2 T-channels in the peripheral axons of sensory neurons participates in painful PDN. We postulate that reversing glycosylation of CaV3.2 channels in diabetic animals will reverse abnormal membrane expression of these channels in somas and peripheral axons of nociceptive DRG cells, diminish cellular hyper-excitability, and reverse neuropathic pain progression in vivo. The proposed work is innovative in that a new mechanism for channel regulation will be characterized. It is medically significant because understanding the details of this regulatory pathway will facilitate development of novel drugs targeting steps in this pathway for treatment of painful neuropathies. We expect that this approach may decrease side effects from medication and reduce the potential for drug abuse in patients with painful diabetic neuropathy.

描述（由适用提供）：背侧根神经节（DRG）的疼痛感应感官神经元可以响应诸如糖尿病等病理状况的敏感性（过度兴奋）。由于对这种敏感性的基础机制的知识不足，因此目前对疼痛糖尿病神经病的治疗限于某些非特异性全身药物，例如阿片类药物或加巴喷丁，这可能会引起巨大的副作用，并且具有很高的滥用潜力。最近的研究表明，T通道通过增强伤害感受器的兴奋性对疼痛反应的敏感性做出了以前无法识别的贡献。我们最近表明，糖尿病神经病的链蛋白酶（STZ）诱导的和OB/OB小鼠模型中的DRG T电流被上调，并有助于增强疼痛的传播。在初步数据中，我们表明糖基化抑制剂神经氨酸酶抑制了T-电流并逆转这些动物模型中的热和机械痛觉过敏。这一发现使我们假设CAV3.2通道的翻译后糖基化增加了活性，增强了伤害性DRG神经元的兴奋，因此有助于疼痛的糖尿病神经病的症状。我们的具体目的是：目标1：使用贴片钳记录和生物物理方法研究糖基化诱导的Cav3.2在体外急性解散的DRG神经元中Cav3.2 T通道活性的改变。我们提出，T-电流动力学和密度的改变可以直接影响伤害性DR细胞的刺激。目的2：研究重组细胞，天然和培养的DRG神经元中Cav3.2 T通道糖基化的位点。我们提出，特异性细胞外天冬酰胺保留的糖基化cav3.2通道会增加通道的电流密度和膜表达。目的3：测试以下假设：感觉神经元的周围轴突中Cav3.2 T通道的糖基化参与疼痛的PDN。我们假设糖尿病动物中Cav3.2通道的反向糖基化将反向这些通道的膜膜表达，在伤害感受DRG细胞的躯体和周围轴突中，细胞过度去症状降低，并降低活体内神经性疼痛的进展。拟议的工作是创新的，因为将要表征一种新的通道调节机制。这具有医学意义，因为了解这种调节途径的细节将有助于在治疗疼痛神经病的途径中靶向靶向步骤的新型药物的开发。我们预计这种方法可能会减少药物的副作用，并降低疼痛糖尿病神经病患者的药物滥用潜力。