Regression and shift in composition of coronary atherosclerotic plaques by pioglitazone: insight from an intravascular ultrasound analysis

Efficacy study of olmesartan medoxomil on coronary atherosclerosis progression and epicardial adipose tissue volume reduction in patients with coronary atherosclerosis detected by coronary computed tomography angiography: study protocol for a randomized controlled trial

Background

Epicardial adipose tissue (EAT) is a newly discovered independent risk factor for coronary atherosclerosis. There is a scarcity of information on the reduction of EAT volume to reduce atherosclerosis risk. Coronary computed tomography angiography (CCTA) has emerged as a noninvasive imaging method for the analysis of coronary atherosclerosis and EAT volume. The purpose of this trial is to determine whether olmesartan medoxomil is effective at both treatment of coronary atherosclerosis progression and EAT volume reduction in patients with coronary atherosclerosis detected by CCTA.

Methods/design

This study is a prospective, single-center, open-label, randomized controlled clinical trial aimed at exploring the efficacy of olmesartan medoxomil on coronary atherosclerosis and EAT. A total of 194 patients with coronary stenosis greater than 30 % and less than 70 % detected by CCTA will be randomly divided into olmesartan medoxomil or conventional antihypertensive medication groups (1:1 ratio). The primary outcome measures include coronary atherosclerosis progression and EAT volume reduction, as detected by CCTA at 12 months. The secondary outcome measures include the levels of blood lipids, glucose, high-sensitivity C-reactive protein, IL-6, monocyte chemotactic protein 1, TNF-α, matrix metalloproteinase 9, NO, endothelin 1, adiponectin, and leptin at baseline and after 6 and 12 months.

Discussion

Treatments aimed at reducing EAT volume can eventually achieve an antiatherosclerotic effect. This is the first trial designed to explore the effect of olmesartan medoxomil on both coronary atherosclerosis progression and EAT volume reduction in patients with coronary atherosclerosis detected by CCTA.

Trial registration

ClinicalTrials.gov: NCT02360956.

Effect of peroxisome proliferator-activated receptor gamma agonist on heart of rabbits with acute myocardial ischemia/reperfusion injury

OBJECTIVE

To explore protective effect of rosiglitazone on myocardial ischemia reperfusion injury.

METHODS

A total of 48 male SD rats were randomly divided into control group (A), I/R group(B), high dose of rosiglitazone (C), low dose of rosiglitazone (D). Plasm concentration of creatine kinase (CK), CK-MB, hsCRP, Superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), nitric oxide (NO) and endothelin (ET) were measured 1 h later after I/R. 24 h after I/R hearts were harvested to observe pathological and ultrastructural changes. Immunohistochemistry and western blotting was used to test CD40 expression in myocardial tissue. Area of myocardial infarction were tested, arrhythmia rate during I/R was recorded.

RESULTS

Plasm concentration of creatine kinase (CK), CK-MB, hsCRP, NO, MDA and ET were decreased in group C, D compared with group B. Plasm concentration of T-SOD and GSH-Px was increased significantly in group C, D compared with group B. Compared with group B, pathological and ultrastructural changes in group C, D were slightly. Myocardial infarction area and arrhythmia rate were lower in group C, D compare with group B.

CONCLUSIONS

Rosiglitazone can protect myocardium from I/R injury by enhancing T-SOD and GSH-Px concentration, inhibit inflammatory reaction, improve endothelial function, reduce oxidative stress and calcium overload.

The prevention and regression of atherosclerotic plaques: emerging treatments

Occlusive vascular diseases, such as sudden coronary syndromes, stroke, and peripheral arterial disease, are a huge burden on the health care systems of developed and developing countries. Tremendous advances have been made over the last few decades in the diagnosis and treatment of atherosclerotic diseases. Intravascular ultrasound has been able to provide detailed information of plaque anatomy and has been used in several studies to assess outcomes. The presence of atherosclerosis disrupts the normal protective mechanism provided by the endothelium and this mechanism has been implicated in the pathophysiology of coronary artery disease and stroke. Efforts are being put into the prevention of atherosclerosis, which has been shown to begin in childhood. This paper reviews the pathophysiology of atherosclerosis and discusses the current options available for the prevention and reversal of plaque formation.

Oxidative stress and lectin-like ox-LDL-receptor LOX-1 in atherogenesis and tumorigenesis

Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) has been identified as a major receptor for oxidized low-density lipoprotein (ox-LDL) in endothelial cells, monocytes, platelets, cardiomyocytes, and vascular smooth muscle cells. Its expression is minimal under physiological conditions but can be induced under pathological conditions. The upregulation of LOX-1 by ox-LDL appears to be important for physiologic processes, such as endothelial cell proliferation, apoptosis, and endothelium remodeling. Pathophysiologic effects of ox-LDL in atherogenesis have also been firmly established, including endothelial cell dysfunction, smooth muscle cell growth and migration, monocyte transformation into macrophages, and finally platelet aggregation-seen in atherogenesis. Recent studies show a positive correlation between increased serum ox-LDL levels and an increased risk of colon, breast, and ovarian cancer. As in atherosclerosis, ox-LDL and its receptor LOX-1 activate the inflammatory pathway through nuclear factor-kappa B, leading to cell transformation. LOX-1 is important for maintaining the transformed state in developmentally diverse cancer cell lines and for tumor growth, suggesting a molecular connection between atherogenesis and tumorigenesis.

Intravascular ultrasound: principles and cerebrovascular applications

Intravascular sonography is a valuable tool for the morphologic assessment of coronary atherosclerosis and the effect of pharmacologic and nonpharmacologic interventions on the progression or stabilization of atherosclerosis. An analysis of the different modes, applications, and limitations is provided on the basis of review of existing data from multiple clinical case studies, trials, and mechanistic studies. Intravascular sonography has been used to assess the outcomes of different percutaneous interventions, including angioplasty and stent implantation, and to provide detailed characterization of atherosclerotic lesions, aneurysms, and dissections within the cerebrovascular circulation. Evolution of intravascular sonographic technology has led to the development of more sophisticated diagnostic tools such as color-flow, virtual histology, and integrated backscatter intravascular sonography. The technologic advancement in intravascular sonography has the potential of providing more accurate information prior, during, and after a medical or endovascular intervention. Continued assessment of this diagnostic technique in both the intracranial and extracranial circulation will lead to increased use in clinical practice with the intent to improve outcomes.

The role of glucose lowering agents on restenosis after percutaneous coronary intervention in patients with diabetes mellitus

INTRODUCTION

The prevalence of diabetes is increasing rapidly, and individuals with diabetes are at high risk for cardiovascular disorders. Subsequently the percentage of patients with diabetes subjected to revascularisation, i.e. either percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) also rises rapidly. The outcome of patients with diabetes after PCI is worse than for patients without diabetes. Restenosis is the main limiting factor of the long-term success of PCI. Although stents and antithrombotics improved outcome after PCI in both diabetics and non-diabetics, diabetics still have a worse prognosis. This leads to the suggestion that the restenosis mechanism in diabetics might be different from that in non-diabetics.

CONCLUSION

Several glucose lowering agents have been shown to influence the restenosis process and thus the outcome after PCI. Current data of especially metformin and thiazolidinediones indicate beneficial results as compared to insulin and sulfonylurea on restenosis. However, no large trials have been undertaken in which the effect of glucose lowering agents on restenosis is associated with improved outcome.The purpose of this review is to summarize the effect of diabetes and glucose lowering agents on restenosis.