Targeting accessory proteins of alpha2C adrenergic receptor in Raynaud Phenomenon

雷诺现象中针对 α2C 肾上腺素受体的辅助蛋白

• 批准号: 8913758
• 负责人: Catalin Filipeanu
• 金额: $ 7.55万
• 依托单位: HOWARD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8913758
• 关键词: ATP phosphohydrolase; Adrenergic Antagonists; Adrenergic Receptor; Adverse effects; Affect; Amino Acids; Binding; Biological Markers; Blood Vessels; Calcium Channel; Catecholamines; Cell Line; Cell membrane; Cell surface; Characteristics; Clinical; Clinical Treatment; Clinical Trials; Collaborations; Connective Tissue Diseases; Data; Dependence; Dermatology; Diagnosis; Diagnostic; Disease; Disease model; Early Diagnosis; Early treatment; Effectiveness; Emotional Stress; Endoplasmic Reticulum; Event; Exposure to; Family; Foundations; Future; G-Protein-Coupled Receptors; General Population; Goals; Health; Heat shock proteins; Heat-Shock Proteins 90; Human; Incidence; Individual; Investigation; Left; Limb structure; Lupus Erythematosus; Mediating; Modeling; Molecular; Molecular Chaperones; Molecular and Cellular Biology; Muscle Contraction; Muscle relaxants; Names; Norepinephrine; Numbness; Pain; Pathogenesis; Pathology; Patients; Pattern; Peripheral; Pharmaceutical Preparations; Pharmacological Treatment; Phase; Physiological; Pilot Projects; Plasma; Prevention; Proteins; Proteomics; Rattus; Raynaud Disease; Reticulum; Rodent; Role; Scleroderma; Site; Skin; Smooth Muscle; Smooth Muscle Myocytes; System; Temperature; Testing; Therapeutic; Transfection; Woman; Work; Yohimbine; base; clinically relevant; cold temperature; differential expression; digital; experience; geranylgeranylacetone; golgi associated, gamma adaptin homologous, ADP-ribosylation factor interacting protein; inhibitor/antagonist; member; men; novel; novel strategies; novel therapeutic intervention; novel therapeutics; nucleophosmin; overexpression; pre-clinical; prevent; receptor; response; rottlerin; trafficking; vasoconstriction; vibration

DESCRIPTION (provided by applicant): Raynaud Phenomenon (RP) is characterized by exaggerated vasoconstriction in response to cold, emotional stress and vibrations and comprises from Raynaud's Disease (primary or idiopathic) and Raynaud's Syndrome when is associated with another connective tissue disorder like Lupus erythematosus or scleroderma. Although often underestimated and under diagnosed, RP is a common clinical encounter affecting between 3 to 12% of men and 6 to 20 % of women. Unfortunately, a specific treatment of RP is still missing today, the therapeutic approaches consisting only in administration of general smooth muscle relaxants. Moreover, although the disease was described more than 150 years ago, the RP pathogenesis is still not understood and no biological markers or paraclinical investigations were validated for early detection and treatment. Clinical evidence indicate that yohimbine, an alpha2-adrenergic antagonist (A2) is effective in preventing the vasospastic attacks in RP. Based on the anatomical distribution, A2C is the most probable adrenergic receptor subtype responsible for these effects and this view is supported by experimental evidence indicating that the receptor localization at the functional site is enhanced after exposure to low-temperature. However, currently no specific A2C blockers are available and also these antagonists may have numerous side effects precluding their use in the RP's treatment. An alternative approach is to target the accessory proteins controlling the synthesis, maturation and intracellular trafficking of A2C. Pursuing this idea, during the last few years we identified specific proteins interacting with A2C and regulating its function in temperature-sensitive manner. First, we have shown that HSP90 inhibitors are selectively reducing A2C targeting to the functional site. Further, we compared the intracellular trafficking and functional responses of human and rat A2C and we found that even if they are over 90 % homologous, human A2C displays a much greater temperature-dependence, indicating that the exaggerated vasoconstriction observed in RP can be studied using only the human receptor. We further identified the amino acid residues responsible for this particular pattern, due to the differential interactions with RuVBL1 protein. Accordingly, changes in the RuVBL1 cellular levels induced alterations in the temperature- dependent A2C functional responses. Similarly, increases in the cellular levels of another accessory protein named nucleophosmin, greatly enhanced the temperature-dependent A2C activation. Therefore, based on these original findings, the main goal of the present investigation is to determine using human vascular smooth muscle cells from normal and RP donors if HSP90, RuVBL1 and nucleophosmin may be used as biomarkers for early diagnostic and therapy of RP. As HSP90 inhibitors are currently in second phase clinical trial for the treatment of unrelated diseases, the expected results may have an immediate clinical relevance. Also, we aim to establish a new model to test the effectiveness of current and future therapeutic approaches in RP.

描述(申请人提供)：雷诺现象(RP)的特征是对寒冷、情绪压力和振动做出夸张的血管收缩反应，包括雷诺氏病(原发或特发性)和雷诺氏综合征，当与另一种结缔组织疾病如红斑狼疮或硬皮病有关时。尽管经常被低估和诊断不足，RP是一种常见的临床遭遇，影响到3%至12%的男性和6%至20%的女性。不幸的是，一种特殊的RP治疗方法至今仍然缺乏，治疗方法仅包括使用普通的平滑肌松弛药。此外，尽管该病早在150多年前就已被描述，但其发病机制仍不清楚，也没有生物标志物或临床旁研究被证实用于早期发现和治疗。临床证据表明，α2-肾上腺素能拮抗剂育亨宾(A2)能有效预防RP的血管痉挛发作。根据解剖分布，A2C是最有可能导致这些效应的肾上腺素能受体亚型，这一观点得到了实验证据的支持，实验证据表明，低温暴露后受体在功能部位的定位增强。然而，目前还没有特定的A2C阻滞剂可用，而且这些拮抗剂可能有许多副作用，使它们不能用于RP的治疗。另一种方法是靶向控制A2C的合成、成熟和细胞内转运的辅助蛋白。基于这一想法，在过去的几年里，我们发现了与A2C相互作用的特定蛋白质，并以温度敏感的方式调节其功能。首先，我们已经证明了HSP90抑制剂选择性地减少了针对功能部位的A2C靶向。此外，我们比较了细胞内转运和功能 我们对人和大鼠A2C的反应进行了研究，发现即使它们有90%以上的同源性，人类A2C也表现出更大的温度依赖性，这表明在RP中观察到的夸大的血管收缩可以仅用人类受体来研究。由于差异，我们进一步确定了导致这种特殊模式的氨基酸残基。 与RuVBL1蛋白的相互作用。因此，RuVBL1细胞水平的变化导致了温度依赖的A2C功能反应的变化。同样，另一种名为核磷蛋白的辅助蛋白细胞水平的增加，大大增强了温度依赖的A2C激活。因此，基于这些原始发现，本研究的主要目的是确定HSP90、RuVBL1和核磷蛋白是否可以作为RP的早期诊断和治疗的生物标志物。由于HSP90抑制剂目前处于治疗无关疾病的第二阶段临床试验，预期结果可能具有直接的临床相关性。此外，我们的目标是建立一个新的模型来测试目前和未来的RP治疗方法的有效性。