The Role of Sodium Channel Nav1.7 in Osteoarthritis - Resubmission - 1

骨关节炎是最常见的关节疾病，目前尚无有效的预防或治疗手段。 减缓关节退变。因此，新的骨关节炎相关分子(S)的发现可能在骨质疏松症的发生、发展中起到重要的作用。 形成寻找新的骨性关节炎治疗靶点。我们的RNAseq屏幕，与众不同的新颖之处 在骨关节炎中表达的基因导致了Nav1.7(由SCN9A编码)作为一种新的骨关节炎相关分子的分离。 NAV1.7具有特别重要的意义，因为它与一系列遗传性人类疼痛障碍相关。一个 据报道，SCN9A的核苷酸多态与骨性关节炎患者疼痛敏感性的增加有关。 我们的初步数据显示，在两人的浅表区软骨细胞中，Nav1.7的表达都增加了 骨性关节炎软骨和小鼠骨性关节炎模型的软骨。我们很兴奋地发现，阻止Nav1.7的戏剧性 人软骨细胞膜电位降低。据我们所知，这是第一个证据表明- 提示钠通道在非兴奋性软骨细胞中具有电生理功能。超极化 NA1.7阻断软骨细胞导致分泌体/跨膜转运改变 蛋白质的含量。事实上，直接阻断Nav1.7和与收集的条件培养液孵育都是如此 NA1.7抑制剂处理的软骨细胞促进软骨细胞合成代谢，抑制IL-1β诱导的钙化。 代谢障碍。此外，一系列蛋白质组学筛选从Nav1.7阻滞剂处理的HSP70和Midkine中分离出来 条件培养液作为NA1.7在软骨细胞中的两个潜在的关键介体。更重要的是，本地和 口服Nav1.7特异性抑制剂可以保护患者免受骨性关节炎的侵袭，并减少外科手术患者与骨性关节炎相关的疼痛。 赖氨酸和化学诱导性骨性关节炎模型。该应用程序的假设是，Nav1.7在 通过调节软骨细胞膜电位和分泌组谱，促进软骨细胞代谢和骨关节炎的发生 细胞。其具体目的是：(1)阐明Nav1.7调控的分子和细胞机制。 延缓软骨细胞新陈代谢。我们将确定SA#1A)Nav1.7封锁、过度表达和 软骨细胞代谢的缺失；SA#1B)调控NA1.7功能的靶基因 软骨细胞；SA#1C)在Nav1.7阻滞剂处理的条件培养液中的分子决定因素。 NA1.7对软骨细胞的调节；以及SA#1D)NA1.7的辅助因子(S)，这些都参与了NA1.7的调节。 软骨细胞染色。(2)确定Nav1.7在办公自动化的启动和进展中的重要性，以及 涉及的潜在机制。我们将确定NAV1.7的全球消融对骨性关节炎的影响。 地位和进展；SA#2B)软骨细胞表达的Nav1.7对骨关节炎的重要性；SA#2C)依赖于- 对HSP70和Nav1.7中期因子的影响阻断介导对OA的保护；和SA#2D)治疗 药理学NAV1.7受体阻滞剂对骨性关节炎及其相关疼痛的影响。拟议的研究不仅将- Vance通过阐明Nav1.7对软骨细胞和骨性关节炎的调控作用，也可能导致其发生发展 作为治疗骨性关节炎而不仅仅是止痛药的新型疾病修改药物，Nav1.7抑制剂。

Osteoarthritis (OA) is the most common joint disease and currently there is no effective means of preventing or slowing joint degeneration. Thus, identification of new OA-associated molecule(s) may provide invaluable in- formation toward the search for novel therapeutic targets for OA. Our RNAseq screen for novel, differentially expressed genes in OA led to the isolation of Nav1.7 (encoded by SCN9A) as a novel OA-associated molecule. Nav1.7 is of particular significance due to its correlation with a spectrum of hereditary human pain disorders. A nucleotide polymorphism of SCN9A was reported to be correlated with increased pain sensitivity in OA patients. Our preliminary data demonstrated that Nav1.7 was increased in superficial zone chondrocytes in both human OA cartilage and cartilage from a mouse OA model. We were excited to find that blocking Nav1.7 dramatically reduced membrane potential in human chondrocytes. To our knowledge, this is the first evidence demonstrat- ing that sodium channel has electrophysiological function in non-excitable chondrocytes. Hyperpolarization caused by Nav1.7 blockade in chondrocytes results in the alternations of secretome/cross-membrane transport of the proteins. Indeed, both direct blockade of Nav1.7 and incubation with the conditioned medium collected from Nav1.7 inhibitor-treated chondrocytes enhanced chondrocyte anabolism and inhibited IL-1β induced ca- tabolism. Further, a series of proteomics screens isolated HSP70 and midkine from the Nav1.7 blocker-treated conditioned medium as two potential key mediators of Nav1.7 in chondrocytes. More significantly, local and oral delivery of Nav1.7-specific inhibitor protected against OA and reduced OA-associated pain in both surgical- ly- and chemically-induced OA models. The hypothesis of the application is that Nav1.7 plays a pivotal role in chondrocyte metabolism and OA through regulating membrane potential and secretome profiling of chondro- cytes. The Specific Aims are: (1) To elucidate the molecular and cellular mechanisms by which Nav1.7 regu- lates chondrocyte metabolism. We will determine SA#1A) the effects of Nav1.7 blockade, overexpression and deletion on chondrocyte metabolism; SA#1B) the target genes of Nav1.7 that mediate the functions of Nav1.7 in chondrocytes; SA#1C) the molecular determinants in Nav1.7 blocker-treated conditioned medium which medi- ate Nav1.7 regulation of chondrocytes; and SA#1D) the co-factor(s) of Nav1.7 that are involved in Nav1.7 regu- lations of chondrocytes. (2) To define the importance of Nav1.7 in the initiation and progression of OA, and the underlying mechanisms involved. We will determine SA#2A) the effects of global ablation of Nav1.7 on OA ini- tiation and progression; SA#2B) the importance of chondrocyte-expressed Nav1.7 to OA; SA#2C) the depend- ence on HSP70 and midkine of Nav1.7 blockade mediated protection against OA; and SA#2D) the therapeutic effects of pharmacological Nav1.7 blockade on OA and OA-associated pain. Proposed studies will not only ad- vance the field by elucidating Nav1.7 regulation of chondrocytes and OA, but may also lead to the development of Nav1.7 inhibitors as novel diseases-modifying drugs for treating OA rather than just pain relievers.