基因修饰干细胞治疗缺血性心脏病的现状与前景

背景：基因技术联合干细胞植入治疗缺血性心脏病是继单纯干细胞治疗后的一大热点.目的：归纳总结基因修饰及干细胞治疗缺血性心脏病的研究现状.方法：计算机检索PubMed数据库中2000-01/2010-12期间相关文献,检索词为 ＂genetic,stem cells,myocardial infarction＂.选择与基因修饰联合干细胞治疗缺血性心脏病密切相关的的29篇文献进行综述.结果与结论：不同功能的基因对干细胞和/或周围环境进行修饰,改善干细胞及相应的性状,以提高移植干细胞的存活能力、促进缺血心肌及周围的血管新生、改善血管顺应性、增加与宿主心肌细胞的耦联、增强干细胞趋化归巢作用等,提高干细胞治疗缺血性心脏病的效果.随着基因技术与干细胞应用的不断发展,可能在缺血性心脏的临床治疗方面得到广泛的应用.     

干细胞移植治疗缺血性心脏病：临床应用的可行性与安全性

背景：干细胞移植到受损的心脏组织,可以大量分化为心肌细胞,这项研究为缺血性心脏病治疗带来新的希望。目的：探讨干细胞移植治疗缺血性心脏病的可行性与安全性。方法：分析干细胞移植治疗缺血性心脏病安全性和可行性的多种试验方法。REPAIR-AMI试验是一项分析急性心肌梗死后即刻冠脉内移植骨髓祖细胞治疗效果的随机双盲、安慰剂对照的多中心研究;MAGICCell-3-DES试验是评价粒细胞集落刺激因子动员的干细胞疗法的安全性和冠脉内注射动员的外周血干细胞对急性心肌梗死和陈旧性心肌梗死的效果;BOOST试验是心肌梗死后经冠脉移植自体骨髓细胞的随机对照研究。PROTECT-CAD试验是一项随机、对照的直接将干细胞注入心肌治疗慢性缺血性心肌病的临床试验。结果与结论：干细胞移植可以改善左心室的收缩功能和舒张功能以及冠脉血流储备,相关研究也得到验证。对于干细胞移植治疗缺血性心脏病,可以增加左室射血分数,临床事件较少,在药物洗脱支架治疗的基础上,干细胞治疗并不增加再狭窄风险。干细胞移植治疗缺血性心脏病安全可行,未来还需要进行大样本、长时间的大规模多中心的随机对照研究,来进一步评价其疗效和风险。     

干细胞治疗缺血性心肌病的临床研究进展

缺血性心肌病是影响人类健康的主要疾病之一，采用干细胞移植治疗缺血性心肌病已经成为近年来的研究热点。移植干细胞能够促进新生血管形成和心肌组织再生，减少瘢痕面积，改善心肌收缩能力。目前应用干细胞治疗缺血性心肌病的临床试验所得到的治疗结果不尽相同，不同类型的干细胞来源、注射方法及剂量、随访观察时间均可影响临床治疗效果；干细胞移植所涉及的免疫排斥、促肿瘤形成以及其他潜在的安全性问题仍是医学界重点关注的领域。本文就干细胞移植治疗缺血性心肌病临床研究相关的影响因素及其安全问题进行相关阐述。     

C-kit＋心脏干细胞治疗缺血性心脏病：研究现状及面临挑战和发展前景

背景：研究发现C-kit＋心脏干细胞具有高度自我更新能力,能够特异性分化为心脏结构细胞,是目前被认为最有希望以完全心肌再生应用于缺血性心脏病及其他终末期心脏病替代治疗的干细胞类型。目的：就C-kit＋心脏干细胞的发现、来源、特性,心脏干细胞治疗缺血性心脏病的历史和现状,目前心脏干细胞治疗缺血性心脏病存在的问题及可能的解决方法作一综述,从而加强对C-kit＋心脏干细胞特性的理解,以便更好地预测其生物学行为并解决其修复心肌的相关问题。方法：应用计算机检索Pub Med数据库中2003年1月至2014年6月关于心脏干细胞的文献,在标题和摘要中以＂stem cell,C-kit＋cardiac stem cells,cardiac infarction＂为检索词进行检索。选择文章内容与C-kit＋心脏干细胞有关,同一领域文献则选择近期发表或发表在权威杂志文献,最终选择38篇文献进行综述。结果与结论：众多基础实验研究均证明C-kit＋心脏干细胞确实能够明显改善动物模型的心功能,改善心室重构,并且有关临床试验也已经证明其能够改善缺血性心脏病患者的心功能和生活质量。虽然试验中发现移植细胞很快流失,并不能发挥修补替代纤维瘢痕的作用,但是其对心脏的有利作用并不随着种子细胞的流失而停止,而是能够长期存在,主要考虑跟各种细胞因子的旁分泌作用有关。目前应用基因修饰种子细胞改善其移植后驻留率和分化相关问题已经取得了一些积极成果,但是仍然有很多问题需要进一步研究。     

Haematopoietic stem cells and repair of the ischaemic heart

HSCs (haematopoietic stem cells) are multipotent stem cells that give rise to all cells of the blood cell lineage. In recent years, it has been proposed that bone marrow serves as a reservoir for cardiomyogenic precursors and that, following cardiac injury, these stem cells circulate to the site of injury where they contribute to myocardial repair and regeneration. This concept of stem cell plasticity has been controversial and, in fact, several key studies on the cardiomyogenic potential of HSCs have not been reproducible in the hands of independent investigators. Despite this controversy, the clinical community has pushed forward with clinical trials of bone marrow transplantation for the treatment of ischaemic heart disease. The following review summarizes the mechanistic underpinnings of bone marrow transplantation into ischaemic myocardium, focusing on the basic science that forms the foundation of this field, and highlights the controversies and new avenues for research that have emerged. It also describes the current state of the art in clinical trials of bone marrow transplantation for heart failure.     

Clinical manifestations and assessment of ischemic heart disease

This article reviews five clinical techniques for measuring and assessing the manifestations of ischemic heart disease. These measurements are heart rate, blood pressure, electrocardiogram, symptoms, and changes in heart sounds. The data obtained from these measurements are discussed in relation to measurement accuracy and to their clinical significance and relationship with the patient's diagnosis, prognosis, and disease manifestations. These clinical measures provide information that is critical to the decision-making processes for patient programming and safety.     

Mesenchymal stem cells for cardiac cell therapy

Despite refinements of medical and surgical therapies, heart failure remains a fatal disease. Myocardial infarction is the most common cause of heart failure, and only palliative measures are available to relieve symptoms and prolong the patient's life span. Because mammalian cardiomyocytes irreversibly exit the cell cycle at about the time of birth, the heart has traditionally been considered to lack any regenerative capacity. This paradigm, however, is currently shifting, and the cellular composition of the myocardium is being targeted by various regeneration strategies. Adult progenitor and stem cell treatment of diseased human myocardium has been carried out for more than 10 years (Menasche et al., 2001; Stamm et al., 2003), and it has become clear that, in humans, the regenerative capacity of hematopoietic stem cells and endothelial progenitor cells, despite potent proangiogenic effects, is limited (Stamm et al., 2009). More recently, mesenchymal stem cells (MSCs) and related cell types are being evaluated in preclinical models of heart disease as well as in clinical trials (see Published Clinical Trials, below). MSCs have the capacity to self-renew and to differentiate into lineages that normally originate from the embryonic mesenchyme (connective tissues, blood vessels, blood-related organs) (Caplan, 1991; Prockop, 1997; Pittenger et al., 1999). The current definition of MSCs includes plastic adherence in cell culture, specific surface antigen expression (CD105(+)/CD90(+)/CD73(+), CD34(-)/CD45(-)/CD11b(-) or CD14(-)/CD19(-) or CD79α(-)/HLA-DR1(-)), and multilineage in vitro differentiation potential (osteogenic, chondrogenic, and adipogenic) (Dominici et al., 2006 ). If those criteria are not met completely, the term "mesenchymal stromal cells" should be used for marrow-derived adherent cells, or other terms for MSC-like cells of different origin. For the purpose of this review, MSCs and related cells are discussed in general, and cell type-specific properties are indicated when appropriate. We first summarize the preclinical data on MSCs in models of heart disease, and then appraise the clinical experience with MSCs for cardiac cell therapy.     

Sodium-Glucose Cotransporter-2 Inhibitors: Heart Failure and Renal Protection Indications

Sodium-glucose cotransporter-2 inhibitors (SGLT-2is) are a class of oral antihyperglycemic drugs recently added to clinical practice guidelines to manage type 2 diabetes mellitus (T2DM). Recent clinical trials have established significant benefits in using SGLT-2is to treat both heart failure and renal disease. This article aims to explain the clinical benefits of inhibiting sodium-glucose cotransporter-2 proteins in patients with T2DM, renal disease, and heart failure. These authors also seek to guide nurse practitioners in prescribing SGLT-2is. Evidence-based guidance for nurse practitioners to treat T2DM, heart failure, and renal disease is likely to improve patients’ clinical outcomes and decrease associated morbidities.     

老年性心脏瓣膜病变的超声心动图表现及分析

运用二维超声心动图对530例,年龄在50岁以上的老年受检者进行检查,共检查出老年性心脏瓣膜病变78例,占受检总数的14.7%.结果表明:老年性心脏瓣膜病变,以主动脉瓣环钙化和主动脉瓣、二尖瓣钙化为多.但老年性风湿性心脏瓣膜病变应引起警惕,它常表现为“原因不明”的心房纤颤和/或哑型二尖瓣狭窄.钙化性瓣膜病变较少有血流动力学紊乱,不引起明显临床症状,其确切临床意义应引起重视,有待进一步研究.     

组织工程心脏瓣膜种子细胞：来源及应用

背景：应用机械瓣和生物瓣行瓣膜置换是治疗终末期瓣膜病的有效手段,然而他们的临床应用受到多个因素的限制。具备生物活性的组织工程心脏瓣膜有潜力克服机械瓣和生物瓣的不足,选择适宜的种子细胞是组织工程心脏瓣膜研究的一个重要方面,许多成熟的体细胞和干细胞已被用于构建组织工程心脏瓣膜,然而尚未获得理想的结果。 目的：以构成瓣膜的细胞成分为基础,对用于构建组织工程心脏瓣膜的种子细胞、体外细胞种植方法的研究进行综述。 方法：由第一作者基于PubMed数据库和万方数据库应用计算机检索2000年1月至2012年12月相关的文章,英文检索词为＂Tissue engineering,Heart valves,Cell＂,中文检索词为＂组织工程,心脏瓣膜,细胞＂,优选文章内容与组织工程心脏瓣膜种子细胞直接相关,具备针对性和权威性,发表在权威杂志的文章共39篇进行综述。 结果与结论：瓣膜的细胞成分主要是内皮细胞和间质细胞,早期人们常用内皮细胞和成纤维细胞构建组织工程瓣膜,随着干细胞研究的深入,应用搏动性生物反应器种植间充质干细胞具有构建的组织工程瓣膜的潜力。     

Cardiac cell therapy: a treatment option for cardiomyopathy

Cardiomyopathy is a common clinical disorder affecting the heart muscle. This disease process frequently leads to congestive heart failure and will often progress to end-stage heart failure. Present standard of care treatment options for cardiomyopathy include medical management, lifestyle changes, and surgical procedures including left ventricular assist devices as a destiny therapy or bridging to heart transplantation. Even despite advances in drug therapy, mechanical assist devices, and organ transplantation, more than half of the persons with cardiomyopathy will die within 5 years of diagnosis. Small uncontrolled clinical trials have demonstrated cardiac stem cells as a treatment option for cardiomyopathy. The theory for the individual or combined mechanism of action for stem cells includes (1) transdifferentiation to blood vessels or myocardium, (2) fusion with the native dysfunctional myocytes to augment function, and (3) homing that may be a systemic or panacrine response for recruiting other cells, and growth factors to help improve oxygen delivery and myocardial function. The field of cardiac cell therapy is rapidly progressing to gather more data with intermediate-size, double-blinded trials that will demonstrate the safety and efficacy of cell therapy.     

Crossword No 8

While some patients with heart disease have only mild forms and may never develop clinical signs as a result, many animals develop forms of heart disease which are progressive and cause signs of heart failure. Dogs and cats with heart failure generally have a poor prognosis. However, rational treatment can help to relieve the clinical signs and improve the chances of survival.     

Association study between fibronectin and coronary heart disease.

Fibronectin is a known chemoattractant for several cell types that play a role in the wound healing process, including fibroblasts, endothelial cells and macrophages. It also generates a scaffold that allows attachment of other extracellular matrix components. Large amounts of fibronectin have been detected in atherosclerotic plaques, suggesting that it may play a role in the pathogenesis of atherosclerosis. To examine the possible involvement of fibronectin in the etiology of atherosclerotic coronary heart disease, we analyzed four polymorphisms in the human fibronectin gene and determined the plasma fibronectin levels in patients with coronary heart disease (n = 109) and age- and gender-matched controls (n = 123) in Chinese Han people. No significant positive association was observed between these polymorphisms and coronary heart disease. The levels of circulating plasma fibronectin, however, were significantly lower in patients with coronary heart disease (mean +/- SD 245 +/- 87 mg/L) compared with controls (354 +/- 88 mg/L) (p < 0.001). The odds ratio (OR) for plasma fibronectin was 0.94 in a multivariate unconditional logistic regression model (OR = 0.94, 95% CI 0.91-0.96, p < 0.001). We conclude that, in our population, the four fibronectin gene polymorphisms detected are not associated with clinical coronary heart disease. Our data suggest that low circulating fibronectin levels might be a new marker of coronary heart disease.     

心脏干细胞的研究与进展

背景：大量研究证明,哺乳动物心脏中存在心脏自身干细胞,参与心脏的自我更新和内源性修复。目的：就心脏干细胞的来源、分类、特征及心脏病治疗等方面进行综述。方法：由第一作者应用计算机检索PubMed数据库2000-01/2010-12有关心脏干细胞的来源、分化、特征及其在心肌再生方面的文章,检索词为＂Cardiacstemcell＂,包括临床研究和基础研究,排除重复研究和Meta分析,共保留32篇文献进行综述。结果与结论：心脏干细胞是一类存在于心脏组织内能够自我更新及克隆增殖的干细胞,它能够分化为心肌细胞、内皮细胞,参与心脏损伤修复,改善心功能。现已能够通过体外分离培养扩增后移植入动物心脏内,为下一步在临床上应用于人体打下了基础。但成体心脏干细胞自身的稳态平衡和动态变化,及其向心脏功能细胞分化需经历哪些具体过程,有哪些影响因素及如何调控等还不太清楚,需要继续研究以进一步证实。     

Breakthroughs in Cell Therapy for Heart Disease: Focus on Cardiosphere-Derived Cells

The clinical reality of cell therapy for heart disease dates back to the 1990s, when autologous skeletal myoblasts were first transplanted into failing hearts during open-chest surgery. Since then, the focus has shifted to bone marrow–derived cells and, more recently, cells extracted from the heart itself. Although progress has been nonlinear and often disheartening, the field has nevertheless made remarkable progress. Six major breakthroughs are notable: (1) the establishment of safety with intracoronary delivery; (2) the finding that therapeutic regeneration is possible; (3) the increase in allogeneic cell therapy; (4) the effect of increasing mechanistic insights; (5) glimmers of clinical efficacy; and (6) the progression to phase 2 and 3 studies. This article individually reviews these landmark developments in detail and concludes that the field has reached a new phase of maturity where the prospect of clinical impact is increasingly imminent.     

围术期心血管危险因素对骨髓祖细胞的影响简

背景：移植自体骨髓干细胞治疗缺血性心脏病已进行了10余年的临床试验,但试验结果在不同的患者中存在差异。因此,有必要鉴定哪些心血管病患者的危险因素影响骨髓干细胞的水平和功能。目的：观察冠心病患者围术期危险因素对骨髓祖细胞数量及功能的影响。方法：选择44例拟行冠状动脉旁路移植的冠心病患者,采集实验室和临床资料;术中经胸骨穿刺采集骨髓,应用 Ficol 淋巴细胞分离液密度梯度离心法分离骨髓单个核细胞,计数并应用锥虫蓝拒染法检测其活性;应用流式细胞仪分析检测CD34＋、CD133＋和CD34＋CD133＋细胞的水平;应用集落形成试验和细胞迁移试验评价骨髓祖细胞功能。结果与结论：术中经胸骨抽取20 mL骨髓可获得（10-89）×106个骨髓单个核细胞,活性在95%以上,等量的骨髓血获得的骨髓单个核细胞的量与患者年龄之间存在明显负相关关系（n=44,r=-0.788,P=0.001）;流式细胞仪检测 CD34＋细胞占（0.94±0.39）%,CD133＋细胞占（0.46±0.28）%,CD34＋CD133＋细胞占（0.53±0.26）%;糖尿病患者骨髓 CD34＋和 CD133＋细胞水平明显低于非糖尿病患者;高龄、女性和心功能较差与骨髓祖细胞集落形成能力降低有关;CD34＋细胞水平与骨髓单个核细胞的迁移能力存在明显的正相关。结果表明经胸骨应用密度梯度离心法可获得足够数量的骨髓单个核细胞作为缺血性心脏病治疗的供体细胞,年龄、性别、糖尿病、心功能与骨髓单个核细胞数量和功能有关。     

Molecular Imaging of Inflammation in Ischemic Heart Disease

Purpose of Review

Ischemic heart disease is caused by atherosclerosis, the build-up of plaque in the coronary arteries, which can lead to the development of heart attacks and heart muscle damage. Despite the advent of medical and surgical therapy to prevent and treat atherosclerosis and its adverse clinical effects, ischemic heart disease remains a leading cause of morbidity and mortality. Recent studies have suggested that the immune system may play a greater role in the development of plaque rupture and adverse left ventricular remodeling after myocardial infarction. Understanding the molecular processes by which inflammation contributes to the pathophysiology of ischemic heart disease is, therefore, worthwhile. This review focuses on new molecular imaging techniques to visualize immune cells to study their contribution to ischemic heart disease.

Recent Findings

A common technique applied to imaging inflammation in ischemic heart disease is targeting the up-regulation and trafficking of immune cells, which may contribute to the adverse consequences associated with atherosclerosis. In the past 5 years, advances in cell labeling for imaging with PET and MRI, including radioisotopes and nanoparticles, have confirmed that inflammatory cells can be visualized in vivo and in greater abundance in unstable cardiovascular disease and in areas of ischemic damage. The major criticisms of these studies to date include their small sample size, lack of histological correlation, limited association with long-term outcomes, and bias toward macrophage imaging.

Summary

While much progress has been made in imaging inflammation in ischemic heart disease over the past 5 years, additional studies in larger cohorts with histological validation and outcome correlation are needed. Nevertheless, imaging inflammation using PET or MRI has the potential to become an important adjunct tool to improve the diagnosis, risk stratification, and therapeutic monitoring of patients with ischemic heart disease.

     

Site specific gene delivery in the cardiovascular system.

Gene therapy holds great promise for treating both genetic and acquired disorders. However, progress toward effective human gene therapy has been thwarted by a number of problems including vector toxicity, poor targeting of diseased tissues, and host immune and inflammatory activity to name but a few of the challenges. Gene therapy for cardiovascular disease has been the subject of many fewer clinical trials than other disorders such as cancer or cystic fibrosis. Nevertheless, the challenges are comparable. The present paper reports a review of investigations related to our hypothesis that site specific cardiovascular gene therapy represents an approach that can lead to both optimizing efficacy and reducing the impact of gene vector-related systemic adverse effects. We report experimental studies demonstrating proof of principle in three areas: gene therapy for heart valve disease, gene delivery stents, and gene therapy to treat cardiac arrhythmias. Heart valve disease is the second most common indication for open heart surgery and is now only treatable by surgical removal or repair of the diseased heart valve. Our investigations demonstrate that gene vectors can be immobilized on the surface of prosthetic heart valve leaflets thereby enabling a therapeutic genetic modification of host cells around the valve annulus and on the leaflet. Other animal studies have shown that vascular stents used to relieve arterial obstruction can also be used as gene delivery systems to provide therapeutic vector constructs that can both locally prevent post stenting reobstruction, known as in-stent restenosis, and treat the underlying vascular disease. Cardiac arrhythmias are the cause of sudden death due to heart disease and affect millions of others on a chronic basis. Our group has successfully investigated in animal studies localized gene therapy using an ion channel mutation to treat atrial arrhythmias.     

Therapeutic angiogenesis with bone marrow--derived stem cells

Despite that advances in medical treatment and interventional procedures have reduced the mortality rate in patients with coronary artery disease, the number of patients with refractory myocardial ischemia and congestive heart failure is rapidly increasing. Experimental studies have demonstrated that bone marrow (BM) contains adult stem cells that can induce neovascularization and improve heart function in ischemic myocardium. Recent insights into the understanding of the mechanisms involved in proliferation, recruitment, mobilization, and incorporation of BM-derived stem cells into the myocardium and blood vessels have prompted development of cellular transplantation therapy for heart diseases refractory to conventional therapy. Initial preliminary clinical studies indicated potential clinical benefit of BM therapy in patients with acute myocardial infarction and chronic myocardial ischemia. Nevertheless, many obstacles remain, such as long-term safety and optimal timing and treatment strategies for BM cell therapy, and these issues need to be addressed in rationally designed, randomized clinical trials.     

New advances and novel treatments in heart failure

As briefly summarized in this report, the prevalence of heart failure is high and it will continue to rise as the population ages. There will be over 1 million hospitalizations for acutely decompensated heart failure this year. The goals of treatment for patients with acutely decompensated heart failure are to lower cardiac filling pressures, remove fluids and improve symptoms of dyspnea, decrease vascular resistance, and increase cardiac output without activating the RAAS. There are few guidelines for the treatment of individuals with acutely decompensated heart failure and many different agents have been used in patients with this disease. Many of these drugs are not completely effective and may lead to serious adverse events. BNP is a natural protein produced by myocardial cells in response to ventricular distension, and its level is dramatically increased in patients with heart failure. The results of several recent clinical trials have shown that administration of nesiritide is safe and highly effective for the initial treatment of patients with acutely decompensated heart failure and can help physicians and nurses meet treatment goals for the management of patients with this serious condition.