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（由申请人提供）：背根神经节（DRG）的疼痛感觉神经元可以响应糖尿病等病理状况而变得敏感（过度兴奋），由于对这种敏感机制的了解不足，目前的疼痛治疗方法。糖尿病神经病变仅限于一些非特异性全身药物，例如阿片类药物或加巴喷丁，它们可能会引起显着的副作用，并且有很高的滥用可能性。我们最近发现，在链脲佐菌素 (STZ) 诱导的糖尿病神经病变模型和 ob/ob 小鼠模型中，DRG T 电流上调，并有助于增强疼痛反应的敏感性。初步数据表明，糖基化抑制剂神经氨酸酶可抑制 T 电流并逆转这些动物的热和机械痛觉过敏。这一发现使我们认识到 CaV3.2 通道的翻译后糖基化会增加活性，增强伤害性 DRG 神经元的兴奋性，从而导致疼痛性糖尿病神经病变的症状：目标 1：为了使用膜片钳记录和生物物理方法来研究体外急性分离的 DRG 神经元中糖基化诱导的 CaV3.2 T 通道活性的改变。 T 电流动力学和密度的改变可以直接影响伤害性 DR 细胞的兴奋性目标 2：研究重组细胞、天然和培养的 DRG 神经元中 CaV3.2 T 通道糖基化发生的位点。 CaV3.2 通道的特定细胞外天冬酰胺残基会增加通道的电流密度和膜表达。目的 3：检验糖基化的假设。我们假设逆转糖尿病动物中 CaV3.2 通道的糖基化将逆转这些通道在伤害性 DRG 细胞的体细胞和外周轴突中的异常膜表达，从而减少。所提出的工作具有创新性，因为将描述通道调节的新机制，因为了解其细节具有医学意义。该调节途径将促进针对该途径中治疗疼痛性神经病的新药物的开发，我们期望这种方法可以减少药物的副作用，并减少患有疼痛性糖尿病神经病的患者滥用药物的可能性。