Effect of cerivastatin on endothelial dysfunction and aortic CD36 expression in diabetic hyperlipidemic rats

Highly upregulated expression of CD36 and MSR1 in circulating monocytes of patients with acute coronary syndromes

Acute Coronary Syndromes (ACS) are a group of disorders caused by the significant reduction of circulation in coronary arteries. The most common reason of the dysfunction is a blood clot formed in place of plaque rupture. The role of scavenger receptors in development and progression of atherosclerosis has been confirmed in many animal experiments, however the knowledge about contribution of the receptors in the development of ACS symptoms in humans still remains insufficient. The aim of this work was to define the expression of two scavenger receptors: CD36 and MSR1 in monocytes of patients with ACS after the onset of symptoms and after the 6 months of treatment. The analysis of CD36 and MSR1 expression was carried out with the use of real-time PCR and flow cytometry. Analyses of lipid and glucose concentration in blood and the level of inflammatory markers in plasma were performed additionally for all ACS patients. All data obtained during the research were analyzed using statistical tests, such as Mann Whitney test, Wilcoxon test, or correlation. In all patients with symptoms of ACS the amount of CD36 and MSR1 mRNA in circulating monocytes, as well as the density of both receptors on the cells surface was significantly higher. Re-analysis of subjects after 6 months of treatment, showed a significant decrease in the CD36 and MSR1 expression in all patients who received atorvastatin. The results of presented studies demonstrate that both investigated receptors are involved in the development and/or progression of ACS.

Molecular basis of human CD36 gene mutations

CD36 is a transmembrane glycoprotein of the class B scavenger receptor family. The CD36 gene is located on chromosome 7 q11.2 and is encoded by 15 exons. Defective CD36 is a likely candidate gene for impaired fatty acid metabolism, glucose intolerance, atherosclerosis, arterial hypertension, diabetes, cardiomyopathy, Alzheimer disease, and modification of the clinical course of malaria. Contradictory data concerning the effects of antiatherosclerotic drugs on CD36 expression indicate that further investigation of the role of CD36 in the development of atherosclerosis may be important for the prevention and treatment of this disease. This review summarizes current knowledge of CD36 gene structure, splicing, and mutations and the molecular, metabolic, and clinical consequences of these phenomena.

Molecular basis of human CD36 gene mutations

CD36 is a transmembrane glycoprotein of the class B scavenger receptor family. The CD36 gene is located on chromosome 7 q11.2 and is encoded by 15 exons. Defective CD36 is a likely candidate gene for impaired fatty acid metabolism, glucose intolerance, atherosclerosis, arterial hypertension, diabetes, cardiomyopathy, Alzheimer disease, and modification of the clinical course of malaria. Contradictory data concerning the effects of antiatherosclerotic drugs on CD36 expression indicate that further investigation of the role of CD36 in the development of atherosclerosis may be important for the prevention and treatment of this disease. This review summarizes current knowledge of CD36 gene structure, splicing, and mutations and the molecular, metabolic, and clinical consequences of these phenomena.

Statins and foam cell formation: Impact on LDL oxidation and uptake of oxidized lipoproteins via scavenger receptors

The uptake of oxidized lipoproteins via scavenger receptors and the ensuing formation of foam cells are key events during atherogenesis. Foam cell formation can be reduced by treatment with 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins). The efficacy of statins is evidently due not only to their cholesterol-lowering properties, but also to lipid-independent pleiotropic effects. This review focuses on lipid-independent pleiotropic effects of statins that influence foam cell formation during atherogenesis, with special emphasis on oxidative pathways and scavenger receptor expression.

Renoprotective effect of pravastatin in salt-loaded Dahl salt-sensitive rats

The pathophysiological features of nephrosclerosis may be analogous to those of atherosclerosis, which is intimately related to lipid metabolism. Thus, we examined whether a lipid-lowering agent, pravastatin, would ameliorate renal damage in hypertensive model animals. Salt-loaded Dahl salt-sensitive (S) rats were given pravastatin (2 mg/ml in drinking water) for 5 weeks. Pravastatin decreased systolic blood pressure. Although pravastatin did not influence the serum total, high-density, or low-density lipoprotein cholesterol, serum triglycerides were decreased. Pravastatin decreased urinary protein excretion and ameliorated histopathological damage in salt-loaded Dahl S rats. Increased urinary excretion of 8-iso-prostagaldin F2alpha and 8-hydroxy-2'-deoxyguanosine and renal superoxide overproduction and decreased reduced glutathione in the renal parenchyma were ameliorated with pravastatin in Dahl S rats fed a high salt diet. Therefore, pravastatin inhibited the progression of renal injury in salt-loaded Dahl S rats, through its antioxidant as well as its depressor effects.

Azelnidipine Down-Regulates Renal Angiotensin-Converting Enzyme and Mineralocorticoid Receptor mRNA in Diabetic Hypertensive Rats

Effects of a new lipophilic L-type calcium channel blocker, azelnidipine, on the expression of molecular components of the renin-angiotensin-aldosterone system (RAAS) were assessed. Male Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a model of diabetes with hypertension, and their lean littermates, Long-Evans Tokushima Otsuka (LETO) rats, were treated with azelnidipine for 2 weeks. The renal cortical mineralocorticoid receptor mRNA in OLETF was higher than in LETO, but was suppressed (P<0.05) by azelnidipine. Renal cortical angiotensin-converting enzyme mRNA of OLETF was lower than that of LETO rats, and it was further suppressed by azelnidipine (P<0.05). Azelnidipine can down-regulate the gene expression of molecular components of RAAS.

Pharmacogenomics and cardiovascular drugs: need for integrated biological system with phenotypes and proteomic markers

Personalized medicine is based on a better knowledge of biological variability, considering the important part due to genetics. When trying to identify involved genes and their products in differential cardiovascular drug responses, a five-step strategy is to be followed: 1) Pharmacokinetic-related genes and phenotypes (2) Pharmacodynamic targets, genes and products (3) Cardiovascular diseases and risks depending on specific or large metabolic cycles (4) Physiological variations of previously identified genes and proteins (5) Environment influences on them. After summarizing the most well-known genes involved in drug metabolism, we will take as example of drugs, the statins, considered as very important drugs from a Public-Health standpoint, but also for economical reasons. These drugs respond differently in human depending on multiple polymorphisms. We will give examples with common ApoE polymorphisms influencing the hypolipemic effects of statins. These drugs also have pleiotropic effects and decrease inflammatory markers. This illustrates the need to separate clinical diseases phenotypes in specific metabolic pathways, which could propose other classifications, of diseases and related genes. Hypertension is also a good example of clinical phenotype which should be followed after various therapeutic approaches by genes polymorphisms and proteins markers. Gene products are under clear environmental expression variations such as age, body mass index and obesity, alcohol, tobacco and dietary interventions which are the first therapeutical actions taken in cardiovascular diseases. But at each of the five steps, within a pharmacoproteomic strategy, we also need to use available information from peptides, proteins and metabolites, which usually are the gene products. A profiling approach, i.e., dealing with genomics, but now also with proteomics, is to be used. In conclusion, the profiling, as well as the large amount of data, will more than before render necessary an organized interpretation of DNA, RNA as well as proteins variations, both at individual and population level.