Li Jian-Jun, Chen Ji-Lin
Department of Cardiology, Fuwai Hospital, Chinese Academy of Medical Science and Cardiovascular Institute, Peking Union Medical College, Beijing 100037, PR China.
Med Hypotheses. 2005;64(5):925-9. doi: 10.1016/j.mehy.2004.10.016.
Pathogenesis of the atherosclerotic process is deemed as multi-factorial, and characterized by chronic inflammatory response. Although hypertension is known to be one of the most important risk factors for atherosclerosis in causasians, its relative contribution to early atherosclerosis are still unknown. Increased evidence has indicated that hypertension, through the vasoactive peptides, such as angiotensin and endothelin-1, promotes and accelerates the atherosclerotic process via inflammatory mechanisms. In animal and human studies pro-inflammatory properties of angiotensin II has been demonstrated in large conduit and small arteries, in the kidney as well as in the heart. Activation of oxidative stress by angiotensin II is a key component of this process. Angiotensin II stimulates nicotinamide adenine dinucleotide phosphate/nicotinamide adenine dinucleotide oxidase in endothelium, smooth muscle cells, and the adventitia of blood vessel to generate reactive oxygen species, leading to endothelial dysfunction, growth, and inflammation, upregulation of endothelin-1, adhesion molecules, nuclear factor-kappa B, and other inflammatory mediators, as well as increased breakdown of nitric oxide and uncoupling of nitric oxide synthase, contribute to the progression of vascular disease and atherogenesis. In addition, recent advances concerning role of endothelin-1 as another important mediator of chronic inflammation in the vascular wall has been documented, and relationship between endothelin-1 and angiotensin II on vascular inflammation demonstrated. Inflammatory mechanisms, therefore, are important participants in the pathophysiology of hypertension-related cardiovascular disease, including atherosclerosis. In experimental models as well as human studies of atherosclerosis, angiotensin converting enzyme inhibitors or angiotensin II receptor blockers have demonstrated the ability to prevent or reverse the progression of atherosclerosis, which was in part associated with decreased expression of inflammatory mediators and improve endothelial functions. Based on those increasing evidence, we hypothesize that inflammation may be a bridge connecting hypertension and atherosclerosis.
动脉粥样硬化过程的发病机制被认为是多因素的,其特征为慢性炎症反应。尽管高血压是白种人动脉粥样硬化最重要的危险因素之一,但其对早期动脉粥样硬化的相对作用仍不清楚。越来越多的证据表明,高血压通过血管活性肽,如血管紧张素和内皮素-1,经由炎症机制促进和加速动脉粥样硬化过程。在动物和人体研究中,血管紧张素II的促炎特性已在大血管和小动脉、肾脏以及心脏中得到证实。血管紧张素II激活氧化应激是这一过程的关键组成部分。血管紧张素II刺激内皮细胞、平滑肌细胞和血管外膜中的烟酰胺腺嘌呤二核苷酸磷酸/烟酰胺腺嘌呤二核苷酸氧化酶以产生活性氧,导致内皮功能障碍、生长和炎症,内皮素-1、黏附分子、核因子-κB和其他炎症介质的上调,以及一氧化氮的分解增加和一氧化氮合酶的解偶联,都有助于血管疾病的进展和动脉粥样硬化的发生。此外,关于内皮素-1作为血管壁慢性炎症的另一个重要介质的作用的最新进展已有记载,并且内皮素-1与血管紧张素II在血管炎症方面的关系也已得到证实。因此,炎症机制是高血压相关心血管疾病(包括动脉粥样硬化)病理生理学中的重要参与者。在动脉粥样硬化的实验模型以及人体研究中,血管紧张素转换酶抑制剂或血管紧张素II受体阻滞剂已证明有能力预防或逆转动脉粥样硬化的进展,这部分与炎症介质表达的降低和内皮功能的改善有关。基于这些越来越多的证据,我们推测炎症可能是连接高血压和动脉粥样硬化的桥梁。