Prevention of high fat diet-induced vascular injury

预防高脂饮食引起的血管损伤

• 批准号: 8610941
• 负责人: MING-HUI ZOU
• 金额: $ 26万
• 依托单位: UNIVERSITY OF OKLAHOMA HLTH SCIENCES CTR
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-15 至 2015-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8610941
• 关键词: 26S proteasome; 5' -AMP-activated protein kinase; AMP-activated protein kinase kinase; Adenoviruses; Aftercare; Aging; Aorta; Apolipoprotein E; Arachidonic Acids; Atherosclerosis; Attenuated; Biological Assay; Blood Vessels; CaM kinase I activator; Cardiovascular Diseases; Cardiovascular system; Cattle; Cells; Cessation of life; Chronic; Clinical Trials; Consumption; Coronary heart disease; Data; Diabetes Mellitus; Diet; Disease; Docosahexaenoic Acids; Dominant-Negative Mutation; Dose; Eicosapentaenoic Acid; Endothelial Cells; Endothelium; Epidemiologic Studies; Event; Fatty acid glycerol esters; Fish Oils; Genetic; Goals; Human; Hypertension; In Vitro; Injury; Knock-out; Laboratories; Lesion; Low Density Lipoprotein Receptor; MG132; Mediating; Metabolism; Molecular; Mus; NF-kappa B; Nuclear Translocation; Obesity; Omega-3 Fatty Acids; Oxidases; Oxidative Stress; Patients; Peroxisome Proliferator-Activated Receptors; Phosphorylation; Physiological; Polyunsaturated Fatty Acids; Prevention; Production; Proteasome Inhibitor; Proteins; Relaxation; Role; STK11 gene; Signal Transduction; Small Interfering RNA; Superoxides; TNFRSF5 gene; Techniques; Testing; Time; Transactivation; Umbilical vein; Vascular Diseases; Work; activity marker; endothelial dysfunction; gain of function; in vivo; insight; loss of function; multicatalytic endopeptidase complex; neutrophil cytosol factor 67K; novel; overexpression; p65; protective effect; public health relevance; receptor; response; therapeutic target; vascular inflammation

DESCRIPTION (provided by applicant): Overwhelming data from epidemiological studies and clinical trials reveal that consumption of fish oils (omega-3 polyunsaturated fatty acids) reduces cardiovascular deaths (CVD) and retards the progression of atherosclerosis in patients with coronary heart diseases. However, the cellular and molecular mechanisms by which omega-3 polyunsaturated fatty acids exert their protective effects remain poorly understood. Exciting data from the applicant's laboratory has revealed that administration of omega-3 polyunsaturated fatty acids significantly increased the phosphorylation of AMPK at Thr172 and AMPK activity. Activation of AMPK suppresses 26S proteasomes, the activation of nuclear factor kappa B, and the expression of NAD(P)H oxidase. Consistently, genetic deletion of AMPK12 in either ApoE knockout (Apo E-/-) or LDL receptor knockout (LDLr-/-) strain markedly increased 26S proteasome activity, I?B degradation, NF:B transactivation, NAD(P)H oxidase subunit overexpression, oxidative stress, endothelial dysfunction, and atherosclerosis, all of which were largely suppressed by chronic administration of MG132, a potent and cell permeable proteasome inhibitor. The central hypothesis of the current application is that selective activation of AMPK by omega-3 polyunsaturated fatty acids inhibits 26S proteasomes and NF-?B-mediated overexpression of NAD(P)H oxidase resulting in decreased oxidative stress, a key factor in vascular injury caused by high fat diets (HFD). Comprehensive experimental approaches including pharmacological and genetic means (siRNA and adenoviruses) will be used (1) to establish the essential roles of AMPK activation in omega-3 polyunsaturated fatty acids-induced suppression of NF:B-mediated aberrant expression of NAD(P)H oxidase in endothelial cells; (2) to elucidate the central roles of AMPK and 26S proteasome in omega-3 polyunsaturated fatty acids-induced inhibition on NF:B- mediated overexpression of NAD(P)H oxidase in endothelial cells; (3) to dissect the molecular mechanisms by which AMPK suppresses 26S proteasome activity, and (4) to assess the effects of AMPK on endothelial function and atherosclerosis in mice with the endothelium-specific depletion of AMPK (Tg-Cre-AMPK 11 or 12 (flox/flox), loss-of function) or in mice with the endothelium-specific overexpression of a constitutively active AMPK (Tg-CAAMPK, gain-of-function) in vivo. This powerful combination of in vitro and in vivo techniques and gain-/loss-of-function approaches will yield important insights into how omega-3 polyunsaturated fatty acids protect against cardiovascular diseases. Importantly, completion of the proposed studies will also provide novel insights into whether 26S proteasomes and AMPK are potential therapeutic targets for countering atherosclerosis associated with common diseases including aging, obesity, diabetes, and hypertension.

描述（由申请人提供）：来自流行病学研究和临床试验的大量数据表明，食用鱼油（omega-3多不饱和脂肪酸）可减少冠心病患者的心血管死亡（CVD）并延缓动脉粥样硬化的进展。然而，omega-3多不饱和脂肪酸发挥其保护作用的细胞和分子机制仍然知之甚少。来自申请人实验室的令人兴奋的数据显示，omega-3多不饱和脂肪酸的施用显著增加了AMPK在Thr172位点的磷酸化和AMPK活性。AMPK的激活抑制26S蛋白酶体、核因子κ B的激活和NAD(P)H氧化酶的表达。同样，在ApoE敲除（Apo E-/-）或LDL受体敲除（LDLr-/-）菌株中，AMPK12基因缺失均显著增加26S蛋白酶体活性。B降解、NF:B反式活化、NAD(P)H氧化酶亚基过表达、氧化应激、内皮功能障碍和动脉粥样硬化，所有这些都在很大程度上被长期服用MG132（一种有效的细胞渗透性蛋白酶体抑制剂）所抑制。当前应用的中心假设是ω -3多不饱和脂肪酸选择性激活AMPK抑制26S蛋白酶体和NF-？b介导的NAD(P)H氧化酶的过度表达导致氧化应激降低，这是高脂肪饮食（HFD）引起血管损伤的关键因素。包括药理学和遗传学手段（siRNA和腺病毒）在内的综合实验方法将被使用(1)来确定AMPK激活在omega-3多不饱和脂肪酸诱导的NF: b介导的内皮细胞NAD(P)H氧化酶异常表达的抑制中的重要作用；(2)阐明AMPK和26S蛋白酶体在omega-3多不饱和脂肪酸诱导的内皮细胞NF:B介导的NAD(P)H氧化酶过表达抑制中的核心作用；(3)剖析AMPK抑制26S蛋白酶体活性的分子机制，(4)评估AMPK对内皮特异性AMPK缺失（Tg-Cre-AMPK 11或12 (flox/flox)，功能丧失）的小鼠内皮功能和动脉粥样硬化的影响，或在体内内皮特异性过表达组成活性AMPK （Tg-CAAMPK，功能获得）的小鼠。这种体外和体内技术以及功能增益/丧失方法的强大结合将对omega-3多不饱和脂肪酸如何预防心血管疾病产生重要见解。重要的是，拟议研究的完成还将为26S蛋白酶体和AMPK是否是对抗与常见疾病（包括衰老、肥胖、糖尿病和高血压）相关的动脉粥样硬化的潜在治疗靶点提供新的见解。