Activation of GPR37 and GPR37L1 by prosaptide, a neuroprotective peptide

Prosaptide（一种神经保护肽）激活 GPR37 和 GPR37L1

• 批准号: 8550157
• 负责人: Randy A. Hall
• 金额: $ 22.58万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-24 至 2014-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8550157
• 关键词: 1-Methyl-4-phenylpyridinium; Acute; Agonist; Amino Acids; Animal Model; Animals; Area; Astrocytes; Binding; Biological Assay; Brain; Brain region; Cell membrane; Cell model; Cells; Cerebrum; Cessation of life; Chronic; Clinical; Cyclic AMP; Disease; Dose; Employee Strikes; Endothelin; Endothelin Receptor; Forskolin; Future; G-Protein-Coupled Receptors; Goals; Knockout Mice; Ligands; Mediating; Midbrain structure; Mus; Nerve; Neuraxis; Neuroglia; Neurons; Neuropathy; Neuropeptides; Neurotoxins; Oligodendroglia; Orphan; Parkinson Disease; Peptides; Physiological; Population; Protein Precursors; Proteins; Regimen; Relative (related person); Role; Scaffolding Protein; Sequence Homology; Signal Pathway; Signal Transduction; Stroke; Substantia nigra structure; Testing; Toxic effect; Toxin; Transfection; Wild Type Mouse; Withdrawal; Work; cell type; dopaminergic neuron; human GPRC5C protein; improved; in vivo; interest; mouse model; myelination; neuronal survival; novel therapeutics; painful neuropathy; parkin gene/protein; prevent; prosaptide; protective effect; public health relevance; receptor; receptor internalization; remyelination; research study; small molecule; trafficking

DESCRIPTION (provided by applicant): GPR37 and GPR37L1 are orphan G protein-coupled receptors that are most abundantly expressed in the central nervous system. We assessed potential activation of GPR37 and GPR37L1 by a handful of orphan neuropeptides and found that both receptors can be activated in transfected non-neuronal cells by prosaptide, which is a 14-amino-acid peptide derived from the precursor protein prosaposin. Prosaptide is known to exert neuroprotective actions in certain areas of the brain, such as the substantia nigra, via unidentified G protein-coupled receptors, and also known to exert beneficial effects in vivo on relieving neuropathic pain and promoting remyelination in animal models of nerve damage. The overall goals of the experiments described in this exploratory R21 application are to test whether GPR37 and/or GPR37L1 mediate the ability of prosaptide to stimulate survival signaling in primary neurons and promote the survival of dopaminergic neurons in vivo. The signaling studies will focus on primary cultures of dopaminergic neurons from the ventral mesencephalon and cortical neurons, which preferentially express GPR37 vs. GPR37L1, respectively. Cultures will be prepared from wild-type mice as well as from mice that are null for expression of GPR37 ("GPR37-KO") or GPR37L1 ("GPR37L1-KO"). The ability of prosaptide to stimulate phospho-ERK and phospho-Akt in these neurons will then be assessed in cultures prepared from the WT vs. KO mice. In addition to these experiments studying the effects of prosaptide on survival signaling, we will also challenge the neurons with insults (such as trophic factor withdrawal or treatment with the toxin MPP+) in the absence and presence of varying doses of prosaptide to assess the effects of the peptide on neuronal survival. In parallel with the experiments on cultured neurons, the whole-animal studies will assess the neuroprotective effects of prosaptide on dopaminergic neurons in the substantia nigra following treatment with the dopaminergic neurotoxin MPTP. We will employ 2 different MPTP regimens (both acute and chronic) to assess the role of GPR37 and GPR37L1 in the neuroprotective effects of prosaptide in vivo. These MPTP toxicity studies will be performed in parallel with WT, GPR37-KO and GPR37L1-KO mice. If the work described in this proposal can establish GPR37 and/or GPR37L1 as the receptor(s) that mediate the neuroprotective actions of prosaptide in primary neuronal cultures and in vivo, then future studies can focus on the discovery of small molecule agonists and/or positive allosteric modulators of these receptors that might serve as novel therapeutics in the treatment of Parkinson's Disease, stroke, neuropathic pain and myelination disorders.

描述（由申请人提供）：GPR37和GPR37L1是孤儿G蛋白偶联受体，在中枢神经系统中最丰富。我们通过少数孤儿神经肽评估了GPR37和GPR37L1的潜在激活，发现两种受体都可以通过prosaptide在转染的非神经元细胞中激活，这是一种源自前体蛋白蛋白质蛋白质蛋白蛋白质蛋白的14-氨基酸肽。已知Prosaptide通过未识别的G蛋白偶联受体在大脑的某些区域（例如底虫）发挥神经保护作用，并且也已知在体内发挥有益的作用，对缓解神经性疼痛的有益作用，并促进在动物模型中促进对神经性疼痛的雷神。 。在本探索性R21应用中描述的实验的总体目标是测试GPR37和/或GPR37L1是否介导prosaptide刺激原发性神经元中生存信号的能力并促进体内多巴胺能神经元的存活。信号传导研究将侧重于分别从腹室中脑和皮质神经元的多巴胺能神经元的原发性培养物，这些神经元分别优先表达GPR37与GPR37L1。培养物将由野生型小鼠以及用于表达GPR37（“ GPR37-KO”）或GPR37L1（“ GPR37L1-KO”）的小鼠的小鼠制备。然后将在WT与KO小鼠中制备的培养物中评估prosaptide在这些神经元中刺激磷酸化和磷酸化的能力。除了这些研究Prosaptide对生存信号传导的影响的实验外，我们还将在不存在和存在各种剂量的Prosaptide的情况下以侮辱（例如营养因子戒断或用毒素MPP+治疗）来挑战神经元，以评估神经元存活的肽。与 在培养的神经元上进行的实验，整个动物研究将评估使用多巴胺能神经毒素MPTP治疗后Nigra中刺激剂对多巴胺能神经元的神经保护作用。我们将采用2种不同的MPTP方案（急性和慢性）来评估GPR37和GPR37L1在体内prosaptide的神经保护作用中的作用。这些MPTP毒性研究将与WT，GPR37-KO和GPR37L1-KO小鼠并行进行。如果该提案中描述的工作可以建立GPR37和/或GPR37L1作为介导Prosaptide在原发性神经培养物和体内的神经保护作用的受体，那么未来的研究可以集中于发现小分子激动剂和/或或/或这些受体的阳性变构调节剂可能是帕金森氏病，中风，神经性疼痛和髓鞘疾病的新型治疗剂。