Rheumatoid arthritis and cardiovascular disease

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease affecting approximately 1% of the adult general population. Cardiovascular disease is recognized as the leading cause of death in RA patients, accounting for nearly 40% of their mortality. Patients with RA are at a twofold increased risk for myocardial infarction and stroke, with risk increasing to nearly threefold in patients who have had the disease for 10 years or more. Congestive heart failure appears to be a greater contributor to excess mortality than ischemia. This increased cardiovascular disease risk in RA patients seems to be independent of traditional cardiovascular risk factors. Pathogenic mechanisms include pro-oxidative dyslipidemia, insulin resistance, prothrombotic state, hyperhomocysteinemia, and immune mechanisms such as T-cell activation that subsequently lead to endothelial dysfunction, a decrease in endothelial progenitor cells, and arterial stiffness, which are the congeners of accelerated atherosclerosis observed in RA patients. This paper discusses pathogenic mechanisms, effects of methotrexate, tumor necrosis factor antagonists, steroids, and statins, with a perspective on therapy.     

Endothelium-targeted gene and cell-based therapies for cardiovascular disease

Most common cardiovascular diseases are accompanied by endothelial dysfunction. Because of its predominant role in the pathogenesis of cardiovascular disease, the vascular endothelium is an attractive therapeutic target. The identification of promoter sequences capable of rendering endothelial-specific transgene expression together with the recent development of vectors with enhanced tropism for endothelium may offer opportunities for the design of new strategies for modulation of endothelial function. Such strategies may be useful in the treatment of chronic diseases such as hypertension, atherosclerosis, and ischemic artery disease, as well as in acute myocardial infarction and during open heart surgery for prevention of ischemia and reperfusion (I/R)-induced injury. The recent identification of putative endothelial progenitor cells in peripheral blood may allow the design of autologous cell-based strategies for neovascularization of ischemic tissues and for the repair of injured blood vessels and bioengineering of vascular prosthesis. "Proof-of-concept" for some of these strategies has been established in animal models of cardiovascular disease. However the successful translation of these novel strategies into clinical application will require further developments in vector and delivery technologies. Further characterization of the processes involved in mobilization, migration, homing, and incorporation of endothelial progenitor cells into the target tissues is necessary, and the optimal conditions for therapeutic application of these cells need to be defined and standardized.     

Circulating Endothelial Cells and Endothelial Progenitor Cells in Obstructive Sleep Apnea

Increased circulating endothelial cells (CECs) have been observed in patients with vascular injury associated with acute myocardial infarction, pulmonary hypertension, and congestive heart failure. Decreased circulating endothelial progenitor cells (EPCs) have been observed in patients with risk factors for cardiovascular disease. Obstructive sleep apnea (OSA) is associated with increased risk of cardiovascular disease and endothelial dysfunction. Subjects were recruited from patients referred for overnight polysomnograms; 17 subjects had OSA and 10 control subjects did not have OSA. All subjects lacked vascular disease and risk factors for vascular disease. Peripheral blood was obtained from fasting subjects in the morning, following sleep studies. CECs and EPCs were quantified using magnetic bead separation with UV epifluorescence microscopy and flow cytometry immunophenotyping, respectively. Cell counts and demographic variables were compared using unpaired t tests. Regression analysis was performed comparing cell counts with the apnea-hypopnea index (AHI) and nadir SaO(2). Subjects with OSA and controls did not differ significantly in terms of age and body mass index. Subjects with OSA had higher AHI, lower nadir SaO(2), and greater sleepiness (Epworth Sleepiness Scale scores). There were no significant differences in CEC (7.0+/-1.5 vs. 4.9+/-0.9, p>0.05) or EPC (1077+/-318 vs. 853+/-176, p>0.05) between controls and OSA cases, respectively. In this small study, we found no differences in CECs or circulating EPCs between patients with OSA and controls. OSA may not be associated with these markers of vascular endothelial cell injury in patients with no concomitant vascular disease.     

Circulating endothelial cells in cardiovascular disease

Quantification of circulating endothelial cells (CECs) in peripheral blood is developing as a novel and reproducible method of assessing endothelial damage/dysfunction. The CECs are thought to be mature cells that have detached from the intimal monolayer in response to endothelial injury and are a different cell population to endothelial progenitor cells (EPCs). The EPCs are nonleukocytes derived from the bone marrow that are believed to have proliferative potential and may be important in vascular regeneration. Currently accepted methods of CEC quantification include the use of immunomagnetic bead separation (with cell counting under fluorescence microscopy) and flow cytometry. Several recent studies have shown increased numbers of CECs in cardiovascular disease and its risk factors, such as unstable angina, acute myocardial infarction, stroke, diabetes mellitus, and critical limb ischemia, but no change in stable intermittent claudication, essential hypertension, or atrial fibrillation. Furthermore, CEC quantification at 48 h after acute myocardial infarction has been shown to be an accurate predictor of major adverse coronary events and death at both 1 month and 1 year. This article presents an overview of the pathophysiology of CECs in the setting of cardiovascular disease and a brief comparison with EPCs.     

Circulating endothelial cells in cardiovascular disease.

Quantification of circulating endothelial cells (CECs) in peripheral blood is developing as a novel and reproducible method of assessing endothelial damage/dysfunction. The CECs are thought to be mature cells that have detached from the intimal monolayer in response to endothelial injury and are a different cell population to endothelial progenitor cells (EPCs). The EPCs are nonleukocytes derived from the bone marrow that are believed to have proliferative potential and may be important in vascular regeneration. Currently accepted methods of CEC quantification include the use of immunomagnetic bead separation (with cell counting under fluorescence microscopy) and flow cytometry. Several recent studies have shown increased numbers of CECs in cardiovascular disease and its risk factors, such as unstable angina, acute myocardial infarction, stroke, diabetes mellitus, and critical limb ischemia, but no change in stable intermittent claudication, essential hypertension, or atrial fibrillation. Furthermore, CEC quantification at 48 h after acute myocardial infarction has been shown to be an accurate predictor of major adverse coronary events and death at both 1 month and 1 year. This article presents an overview of the pathophysiology of CECs in the setting of cardiovascular disease and a brief comparison with EPCs.     

How early in the course of rheumatoid arthritis does the excess cardiovascular risk appear?

Rheumatoid arthritis (RA) is a chronic inflammatory disease which is associated with an increased cardiovascular (CV) burden. Whether the risk is already present at the time of RA diagnosis remains a key area of debate. The aim of this review was to evaluate the existence of both subclinical CV changes, including endothelial dysfunction and atherosclerosis, CV risk factors, as well as CV disease manifestations such as coronary heart disease, myocardial infarction, congestive heart failure and CV death prior to RA diagnosis and during the first few years of the disease. The state of the endothelial function remains controversial in patients with newly diagnosed RA. Studies with impaired brachial artery vasodilatory responses at baseline showed a reversal of the dysfunction after 6-12 months of anti-inflammatory therapy. Morphological evidence of arterial wall atherosclerosis, measured by carotid artery intima-media thickness or the prevalence of carotid plaques, was already present during the first year following RA diagnosis. The risk of coronary heart disease and myocardial infarction is increased even prior to and, at the latest, within 1 year of the clinical onset of RA. The prevalence of hypertension was similar among patients with RA and controls. CV mortality may not increase within the first years of RA diagnosis. In conclusion, the CV risk seems to increase sooner after the RA diagnosis than previously thought. In addition to systematic CV risk assessment, patients with early RA might benefit from being targeted with stricter than conventional CV risk prevention and intervention.     

Endothelial Dysfunction as an Early Sign of Atherosclerosis

The endothelium, the monolayer covering the inner surface of blood vessels, plays a pivotal role in the regulation of vascular tone and structure, as well as vascular inflammation and thrombosis, i.e., of key events of the atherosclerotic disease process and its clinical complications, such as myocardial infarction and stroke. In particular a reduced endothelial availability of nitric oxide (NO), in part due to increased vascular oxidant stress, has been shown to promote a pro-inflammatory and prothrombotic phenotype of the endothelium. More recently, it has been observed that cardiovascular risk factors reduce the number and impair the function of circulating bone marrow-derived endothelial progenitor cells (EPCs), thereby impairing the endogenous endothelial repair capacity.Importantly, endothelial dysfunction has been identified as a common link of all cardiovascular risk factors. Numerous clinical studies have further demonstrated a close association of the degree of endothelial dysfunction with the risk of future cardiovascular events. Whether endothelial dysfunction can improve cardiovascular risk prediction on top of a careful evaluation of classic cardiovascular risk factors is currently prospectively analyzed in several studies, i.e., in the PREVENT-it study. Furthermore, novel easier to use methods to assess endothelial function are currently explored, i.e., the Endo-PAT system, for their potential in improving cardiovascular risk prediction.At present, assessment of endothelial function and EPCs are highly valuable research tools to improve our understanding of mechanisms of vascular disease and to determine the impact of novel therapeutic approaches on vascular function. Before endothelial function measurements can, however, be recommended in clinical practice for cardiovascular risk assessment, the results of ongoing prospective studies assessing the additive value of these measurements for cardiovascular risk prediction should be awaited.     

Targeting Inflammation as a Therapeutic Strategy in Accelerated Atherosclerosis in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease affecting approximately 1% of the population. Patients have reduced life expectancy and the leading cause of death is cardiovascular disease (CVD), with patients experiencing at least a 2‐fold increased risk of myocardial infarction. RA is recognized as an independent risk factor for CVD. Inflammation is a key contributor to the pathogenesis of atherosclerosis and cardiovascular events. As a common catalyst of both diseases, inflammation is the likely cause of increased prevalence of CVD in the RA population. Abating disease‐related inflammation in RA may be an effective strategy in reducing CVD risk. Several other therapies used to modify cardiovascular risk factors in the general population such as statins and angiotensin‐converting enzyme inhibitors are under investigation in patients with RA. This review discusses the parallels in the pathology of RA and atherosclerosis and discusses current therapies for RA and how they affect cardiovascular risk.     

非血脂因素致血管内皮损伤时黏附分子变化的研究进展

随着社会老龄化的加快,动脉粥样硬化的发生率逐年升高。目前认为动脉粥样硬化的始动环节是血管内皮损伤,而脂质代谢异常是血管损伤的主要危险因素。现研究发现一些非脂质物质在血管损伤机制中起着重要的作用,如高同型半胱氨酸、高血糖以及高尿酸等。这些非脂质因素主要作用于血管内皮细胞,通过干扰黏附分子的表达、改变内皮细胞的病理生理状态,进而导致血管内皮的损伤,促进动脉粥样硬化病灶的形成。本文主要介绍非脂质危险因素致内皮损伤时细胞黏附分子的变化的一些作用机制,并介绍干预黏附分子表达的一些治疗靶点,对治疗动脉粥样硬化所导致的冠心病、心肌梗塞等心血管疾病具有重要的临床意义。     

Out-of-hospital sudden cardiac death following myocardial infarction in urban population

Samples of out patient sudden cardiac deaths in Kanagawa Urban prefecture from 1972-1987 and coronary risk factors were studied to determine the increase and/or decrease of myocardial infaction deaths. On the whole death from myocardial infarction increased chronologically, and the rate for females tended to be increased further. The age adjusted myocardial infarction deaths doubled over 10 years, while non-ischemic acute cardiac failure decreased with each generation. Other cardiac diseases tended to be reduced. Cigarette smoking was the highest in advanced countries in male. These findings suggest that deaths from myocard infarction approximately doubled in 10 years in all out-of hospital sudden cardiac deaths. Cigarette smoking from a young age was as great risk as future ischemic heart disease.     

Atherosclerosis in the elderly: a heavy burden to bear

The World Health Organization estimates there are over thirty-two million major atherothrombotic events occur worldwide each year with nearly seventeen million directly attributable deaths.……     

Endothelial progenitor cells:Exploring the pleiotropic effects of statins

Statins have become a cornerstone of risk modification for ischaemic heart disease patients. A number of studies have shown that they are effective and safe. However studies have observed an early benefit in terms of a reduction in recurrent infarct and or death after a myocardial infarction,prior to any significant change in lipid profile. Therefore,pleiotropic mechanisms,other than lowering lipid profile alone,must account for this effect. One such proposed pleiotropic mechanism is the ability of statins to augment both number and function of endothelial progenitor cells. The ability to augment repair and maintenance of a functioning endothelium may have profound beneficial effect on vascular repair and potentially a positive impact on clinical outcomes in patients with cardiovascular disease. The following literature review will discuss issues surrounding endothelial progenitor cell(EPC) identification,role in vascular repair,factors affecting EPC numbers,the role of statins in current medical practice and their effects on EPC number.     

Adult vascular progenitor cells and tissue regeneration in metabolic syndrome

Adult vascular progenitor cells (for example endothelial progenitor cells, EPC) have been studied for their contribution to vascular repair and angiogenesis. These cells can differentiate from bone marrow cells as well as circulating cells carrying hematopoetic stem cell markers. In vivo, they take part in vasculogenesis in different animal models of limb ischemia, myocardial infarction and wound healing. In metabolic disease, the outgrowth and function of EPC in vitro is defective and numbers of EPC correlate with classical risk factors of cardiovascular disease suggesting a role of EPC in the development of vascular complications. Pilot studies for the treatment of myocardial infarction and limb ischemia with autologous bone marrow showed a distinct therapeutic benefit that is presumably mediated by vasculogenesis in damaged tissues. However, little is known about the nature of EPC and their capability to differentiate into functional cells for tissue regeneration. In this article, we review and discuss the hitherto identified physiological function of EPC, the mechanisms leading to dysfunction of these cells and potential therapeutic applications in patients with metabolic syndrome or diabetes mellitus and vascular complications.     

Aging and endothelial dysfunction

Aging is the major risk factor for the development of cardiovascular diseases, the leading cause of morbidity, mortality and disability in western countries. Mounting data suggest that cardiovascular structure and function change with time as result of an "aging process", regarded as an independent process which accompanies aging, interwines and modulates superimposed traditional cardiovascular risk factors to determine the peculiar occurrence, presentations and prognosis of heart disease in the elderly. A whole body of data underlies the impairment of endothelial function due to oxidative stress as a crucial feature of the aging process acting on the cardiovascular system. Insights into molecular and cellular mechanisms of age-associated endothelial dysfunction may provide new strategies to treat age-related cardiovascular diseases.     

线粒体自噬在心血管疾病中的作用

自噬对于组成心血管系统的细胞（如心肌细胞、内皮细胞和血管平滑肌细胞等）的细胞内稳态和生理功能的维持具有重要作用。线粒体自噬是以损伤的线粒体作为自噬底物的一种选择性自噬。由于线粒体是生物能量的主要来源且心血管系统对能量要求较高，线粒体自噬在心血管稳态的维持中尤为重要。研究证实线粒体自噬在心肌梗死、心力衰竭和动脉粥样硬化等疾病中扮演重要角色。本文概述了线粒体自噬的主要调控通路，并阐述了线粒体自噬与心血管疾病之间的密切联系。     

Smoking, blood pressure and serum cholesterol as risk factors of acute myocardial infaction and death among men in Eastern Finland

The impact of smoking, serum cholesterol and blood pressureon the risk of acute myocardial infarction and death due toall causes and cardiovascular diseases was studied in a randomsample of men aged 35 to 59 years from the North Karelia andKuopio counties of Eastern Finland. This is an area with anexceptionally high incidence of coronary heart disease. Altogether,4034 men were studied with a participation rate of 92%. Thesemen were followed-up with a myocardial infarction register anddeath certificate data. During the first five years 256 deathsoccurred among all subjects. There were 66 acute myocardialinfarctions in the North Karelian men reporting no recent coronaryheart disease. Smoking, elevated serum cholesterol and bloodpressure were independently and jointly related to an increasedrisk of acute myocardial infarction and death due to all causesand to cardiovascular disease. Smokers had a 2–3-foldage-adjusted risk of acute myocardial infarction, a 2-2-foldrisk of any death and a 2.1-fold risk of cardiovascular deathcompared with non-smokers. The age-adjusted risk ratios forsystolic blood pressure of 160 mm Hg or more were 1.3, 1.4 and1.9 and those for serum cholesterol at least 8 mmol/l (309 mg/100ml) 2.6, 1.5 and 2.6 concerning myocardial infarction, all deathsand cardiovascular deaths, respectively. All risk ratios exceptthat of systolic blood pressure for acute myocardial infarctionwere significant at levels of at least P < 0.05     

Aldosterone impairs bone marrow-derived progenitor cell formation

Aldosterone has been suggested recently to cause vascular injury by directly acting on the vasculature, in addition to causing injury by raising the blood pressure. Bone marrow-derived endothelial progenitor cells (EPCs) have been shown to exert an important role in the repair of the endothelium. In addition, cell-based therapy using EPCs is emerging as a novel therapeutic strategy for myocardial and peripheral vascular diseases. However, impaired formation and function of EPCs has been observed in patients with risk factors for cardiovascular diseases. We evaluated the possible effects of aldosterone on EPCs by examining the progenitor cell formation from bone marrow mononuclear cells ex vivo. Aldosterone (10 to 1000 nmol/L) reduced the formation of progenitor cells in a concentration-dependent manner. This effect of aldosterone was attenuated by cotreatment with spironolactone. Aldosterone reduced the mRNA levels of vascular endothelial growth factor (VEGF) receptor (VEGFR) 2 without having any effect on the production of VEGF or mRNA levels of VEGF and hepatocyte growth factor in the progenitor cells. However, the expression of stromal-derived growth factor 1 mRNA was paradoxically increased. Consistent with the downregulation of VEGFR-2, VEGF-induced phosphorylation of Akt was abolished in the progenitor cells after aldosterone treatment. N-acetylcysteine, an antioxidant, attenuated the inhibitory effects of aldosterone. These data indicate that aldosterone inhibits the formation of bone marrow-derived progenitor cells, at least partly, by attenuating VEGFR-2 expression and the subsequent Akt signaling. Reduction of aldosterone levels, blockade of mineralocorticoid receptor, and/or cotreatment with antioxidants may, therefore, enhance vascular regeneration by EPCs.     

内皮细胞在缺血性心脏病及心力衰竭中的作用

内皮细胞是上皮细胞的一种,广泛分布于心、血管和淋巴管腔面,在人体生理稳态中参与止血、血管调节、血管生成等重要过程。近年来有研究发现,内皮细胞除上述作用外,还促进了缺血性心脏病等多种疾病的病理进展,并且表现出独特的多向分化能力,其中内皮间质转分化能力与心肌纤维化及心力衰竭关系密切。本文主要探讨血管内皮细胞生理特点及在缺血性心脏病、心力衰竭治疗中的研究进展,为相关疾病治疗提供新思路。     

Resting heart rate as a predictive risk factor for sudden death in middle-aged men

OBJECTIVE: A relative hyperadrenergic tone related to abnormalities of the autonomic nervous system is suspected in the mechanisms of sudden death. Therefore, we assessed the role of an elevated basal heart rate in the occurrence of sudden death in a long-term cohort study. METHODS: 7746 subjects aged 42--53 years, underwent ECG and physical examination conducted by a physician under standardized conditions, provided blood samples for laboratory tests, and answered questionnaires administered by trained interviewers. The vital status was obtained from specific inquiries up to the time of retirement and then by death certificates. Men with known ischemic heart disease were further excluded from analysis which was conducted on the 7079 remaining subjects. RESULTS: After an average follow-up period of 23 years, there were 2083 deaths, among which were 603 cardiovascular deaths including 118 sudden deaths and 192 following myocardial infarction. The crude risk of sudden death increased linearly with the level of resting heart rate and the risk in men in the highest quintile of heart rate was 3.8 fold than in those in the lowest quintile, whereas rates were approximatively twice higher for fatal myocardial infarction, cardiovascular and total mortality (all P<0.01). When age, body mass index, systolic blood pressure, tobacco consumption, parental history of myocardial infarction and parental history of sudden death, cholesterol level, diabetic status, and sport activity were simultaneously entered into the survival model, resting heart rate remained an independent risk factor for sudden death (P=0.03) but not for fatal myocardial infarction. CONCLUSION: An elevated heart rate at rest was confirmed as an independent risk factor for sudden death in middle-aged men.     

Circulating progenitor cells in stable coronary heart disease and acute coronary syndromes: relevant reparatory mechanism?

Bone marrow-derived cells which may be involved in cardiac repair/regeneration after ischaemic injury must undergo mobilisation into peripheral blood with subsequent homing and engraftment into the target organ. Mobilisation of the heterogeneous population of stem/progenitor cells in endothelial injury or myocardial ischaemia has been described recently. The number of circulating stem/progenitor cells reflects the endothelial damage, and turnover may be a surrogate marker reflecting the burden of cardiovascular risk factors and prognostic markers in stable coronary heart disease and acute coronary syndromes. Acute coronary syndromes are associated with increased levels of inflammatory and haematopoietic cytokines which, in turn, can mobilise progenitor cells from the bone marrow. Myocardial infarction increases the number of endothelial progenitor cells and other less well-defined subpopulations, such as CD34/c-kit(+) and CD34/CXCR4(+) cells, which may take part in cardiac repair after ischaemic injury. Data on mobilisation of stem/progenitor cells in acute coronary syndromes are summarised here. Cell types, mechanisms of mobilisation, homing and engraftment are discussed and their relevance to clinical outcomes.