Neurogranin regulation of nitric oxide signaling in cardiovascular disease

项目摘要 精神分裂症患者因心血管疾病而过早死亡的比例高于精神分裂症患者。 一般人口。虽然精神分裂症患者的心血管疾病发病率较高是由于 心血管疾病风险因素增加，新证据表明该患者存在遗传易感性 这可能是心血管疾病风险更高的原因。因此，有必要确定 可能作为精神分裂症和心血管疾病之间的病理生理联系的机械关系 疾病 人类临床研究强调了神经颗粒蛋白（Ng，7.6 kDa）的遗传变异体， 钙调素（CaM）结合蛋白，被认为只在大脑中表达， 精神分裂症有趣的是，我们最近发现，小鼠中Ng的缺失也导致了显著的 心功能不全;它与射血分数和短轴缩短分数降低以及 血管周围纤维化Ng -/-小鼠还显示降低的血浆一氧化氮（NO）水平，指示内皮细胞增殖。 细胞功能障碍，类似于在精神分裂症患者中观察到的内皮型一氧化氮合酶（eNOS）功能障碍。 患者我们的初步研究还表明，Ng在内皮细胞中高度表达， 显着上调响应层流，一个已知的诱导NO生产。因此我们 假设Ng介导内皮细胞中Ca 2+依赖性eNOS活性，并且Ng缺陷 信号传导增加血管阻力，导致心脏纤维化、肥大和最终心力衰竭。 为了验证这一假设，AIM 1将使用体外细胞培养来确定Ng在eNOS信号传导中的机制作用。 接近。我们将测试使用敲除（Ng siRNA和Ng CRISPR/Cas9）是否改变Ng表达。 敲除）和过表达（慢病毒-oNg和慢病毒-dnNg）影响eNOS表达和敏感性 炎症反应。AIM 2还将确定Ng缺失对小鼠心血管功能的影响。 我们将进行血流介导的血管舒张和血管紧张素II输注，以测试Ng-mediated 血管阻力和心力衰竭。这些目标的结果将发现一种新的Ng-eNOS机制， 导致心脏功能障碍的内皮细胞。此外，这些结果将有助于实现我们的目标， 在心血管疾病和精神分裂症之间建立临床干预措施， 心血管疾病的治疗策略。

PROJECT ABSTRACT Schizophrenia patients have a greater rate of premature death from cardiovascular disease compared with the general population. Although the higher incidence of cardiovascular disease in schizophrenia patients is due to increased cardiovascular disease risk factors, new evidence suggests genetic susceptibility in this patient group may account for the greater risk of cardiovascular disease. Therefore, it is pertinent to identify mechanistic relationships that could act as a pathophysiological link between schizophrenia and cardiovascular disease. Human clinical studies highlighted the link between a genetic variant of Neurogranin (Ng, 7.6 kDa), a calmodulin (CaM)-binding protein, thought to be exclusively expressed in the brain, and a risk of developing schizophrenia. Interestingly, we recently discovered that deletion of Ng in mice also resulted in significant cardiac dysfunction; it was associated with decreased ejection fraction and fractional shortening as well as perivascular fibrosis. Ng –/– mice also show decreased plasma nitric oxide (NO) levels, indicative of endothelial cell dysfunction, similar to the endothelial NO synthase (eNOS) dysfunction observed in schizophrenic patients. Our preliminary studies also demonstrated that Ng is highly expressed in the endothelium and significantly up-regulated in response to laminar flow, a known inducer of NO production. Thus, we hypothesize that Ng mediates Ca2+-dependent eNOS activity in the endothelium and that defects in Ng signaling increases vascular resistance resulting in cardiac fibrosis, hypertrophy, and eventually cardiac failure. To test this hypothesis, AIM1 will determine the mechanistic role of Ng in eNOS signaling using in vitro approaches. We will test whether altered Ng expression using knockout (Ng siRNA and Ng CRISPR/Cas9 knockout) and overexpression (Lentivirus-oNg and Lentivirus-dnNg) affect eNOS expression and the sensitivity of eNOS to inflammation. AIM2 will also determine the effect of Ng deletion on cardiovascular function in mice. We will conduct flow-mediated vasodilation and angiotensin II infusion to test the susceptibility of Ng-mediated vascular resistance and cardiac failure. The results of these aims will discover a novel Ng-eNOS mechanism in the endothelium that contributes to cardiac dysfunction. Moreover, these results will contribute to our goal of establishing clinical interventions between cardiovascular disease and schizophrenia and to positively impact treatment strategies for cardiovascular disease.