| BackgroundIt has been found by A number of large-scale epidemiological studies that moderate ethanol consumption can effectively prevent the occurrence of atherosclerosis (AS) and reduce the rate of coronary heart disease (CHD) incidence. Recent studies have showed that ethanol of ethanolic drinks plays an important role in the protection on the cardiovascular system.Aldehyde dehydrogenase2(ALDH2) is one of the key enzymes in ethanol metabolism pathway,which can transform acetaldehyde to acetic acid. In recent years, the new biological functions of ALDH2have gradually been found. Our group and a number of studies abroad confirmed that mutant ALDH2is an independent risk factor for acute coronary syndrome and coronary heart disease. Some studies abroad preliminary discussed the mechanisms that ALDH2participate in AS process, most involved the overall regulation of the body’s HDL-C, inflammatory cytokines and oxidative stress.Our previous study found that moderate ethanol may increase the activity of eNOS in people aortic endothelial cells through activation of ALDH2. eNOS-derived NO is an important factor for cardiovascular protection, regulating hemodynamics and antagonizing the formation and progression of atherosclerosis.However, whether ethanol can play a role in anti-atherosclerotic by ALDH2needs further study.Therefore, we hypothesized that moderate ethanol can activate ALDH2to influence the formation of atherosclerosis, which may provide new targets for prevention and treatment of atherosclerotic disease. Objective:To establish ApoE knocked out mouse model of atherosclerosis, exploring whether ALDH2involves in the effect of ethanol on atherosclerotic plaque formation.Methods:1.Animal feeding and treatment:Six-week ApoE knocked out mice fed a high-fat diet after two-week normal diet,were randomly devided into four groups: normal saline group(NS group), ethanol group(ETOH group), ethanol+NC-siRNA group (ETOH+NC-siRNA group), ethanol+ALDH2-siRNA group(ETOH+NC-siRNA group). ethanol was injected intraperitoneal according to0.3g per kilogram,The normal saline was injected with same proportion,once everyday;and small interfering RNA lentivirus was injected through tail vein, ETOH+NC-siRNA group was injected with negative control virus suspension, ETOH+ALDH2-siRNA group was injected with ALDH2virus suspension,,thus continue high-fat feeding for16weeks.2.Ultrasonography:To ultrasound aortic root from body surface,and measure the aortic root plaque area.3.General inspection:Measuring body weight of the mice before kill them with electronic scale, and taking blood from the left ventricle to detect the level of total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C)and low density f lipoprotein cholesterol (LDL-C).4.Histological staining:After16weeks,To quantify the area of atherosclerotic plaques,mice were executed and the whole aorta were stained with Oil Red O.Frozen sections of the aortic root were used to Oil Red O and HE staining.Measuring the aorta and aortic root plaque by Image Pro-Plus software.5.Western blotting:After the tissues protein were extracted,the protein expression of ALDH2was detected by Western blotting analysis.Using GADPH as internal to quantitative target protein.6.ALDH2activity assay:Using ELISA plate to measure ALDH2activity.7.Statistical Methods:each group of data used mean±standard deviation, using SPSS13.0software for statistical analysis. Each experiment was repeated at least three times independently. For comparison between multiple groups using ANOVA test, pairwise comparisons using SNK test. Correlation analysis using Pearson correlation between variables.P<0.05was indicated statistically significant.Result:1.Atherosclerosis model was successfully constructed.2.General inspection:ethanol or small interfering RNA lentivirus treatment had no significant effect on the body weight of mice (P>0.05); Compared with the NS group, ethanol treatment significantly increased HDL-C (P<0.05); compared with ETOH group and ETOH+NC-siRNA group, ETOH+ALDH2-siRNA reduced HDL-C (P<0.05); ethanol intervention or small interfering RNA lentivirus treatment had no significant effect on TC、TG、LDL-C levels, with no statistical difference (P>0.05).3.Ultrasound shows that compared with the NS group, plaque of ETOH group significantly reduced; plaques of ETOH+ALDH2-siRNA group were increased than those of ETOH group and ETOH+NC-siRNA group. The difference was statistically significant (P<0.01).4.Tissue staining:the oil red O of the whole aorta and the aortic root slices staining had a consistent result, that compared with the NS group, ETOH group reduced the formation of atherosclerotic plaques; compared with ETOH group and ETOH+NC-siRNA group, plaques of ETOH+ALDH2-siRNA group increased significantly. The difference was statistically significant (P<0.01). HE staining could be clearly seen the formation of the atherosclerotic plaque from the aortic root.5.ALDH2protein expression:the expression of ALDH2in ETOH group was significantly increased than those of the NS group; compared with ETOH group and ETOH+NC-siRNA group, the expression of ALDH2in ETOH+ALDH2-siRNA group was decreased. The difference was statistically significant (P<0.01).6.ALDH2activity assay:ALDH2activity of ETOH group was significantly increased than those of the NS group; compared with ETOH group and ETOH+NC-siRNA group, ALDH2activity of ETOH+ALDH2-siRNA group was decreased.The difference was statistically significant (P<0.01). ALDH2activity and HDL-C concentrations showed a linear correlation (r=0.675, P<0.01).Conclusion:ethanol intervention can reduce the formation of atherosclerotic plaques; While ethanol can increase the activity and expression of ALDH2; The protective effect of ethanol on AS is attenuated after ALDH2inhibition, so ethanol can slow the formation of the atherosclerosis by activating ALDH2. Background:In recent years, with the improvement of people’s living standards, the incidence of obesity is increasing year by year. Numberous clinical epidemiological data showed that the risk of obese patients who suffer from hypertension, dyslipidemia, coronary heart disease, diabetes risk was significantly increased, and obesity is an independent risk factor for heart failure. Cardiac remodeling refers that the collagen fiber was excessive accumulated in the myocardial extracellular matrix (extracellular matrix, ECM) caused by collagen metabolism disorders, which led to myocardial fibrosis, thus cardiac structure and function were changed. Studies have shown that obesity can cause ventricular remodeling and left ventricular dysfunction.Peroxisome proliferator-activated receptors (PPAR) is a new member of nuclear hormone receptor superfamily, PPARa is one subtype of them, it was reported that activation of PPARa can reduce Left ventricular hypertrophy and myocardial fibrosis caused by pressure overload. PPARa agonist fenofibrate (fenofibrate) is now widely used in clinical, it had some related research on the impact of fenofibrate on myocardial remodeling caused by hypertension, but the impact of fenofibrate on myocardial remodeling caused by obesity had few report. Therefore, this study was designed to evaluate the cardiac structure and function by echocardiography, combined with histological changes, to explore the effects of fenofibrate on myocardial remodeling in obese rats, so as to provide new ideas on drugs for myocardial remodelingObjective:To assess the effects of fenofibrate on myocardial remodeling in obese rats by echocardiography. Methods:1.Twenty-six SD rats were fed with high fat chow to establish twenty obese rats models,which were randomly divided into two groups:obesity group (OB group,n=10) and fenofibrate group(F group,n=10).The same week-old SD rats group (n=10) was also randomly selected as normal control group.F group was given fenofibrate60mg·kg-1d-1for8weeks,the other groups were given normal saline.2.General examination:Measuring the body weight of the rats and drawing blood from the jugular sinus before and after the experiment; At the end of the experiment,the rats were sacrificed and the hearts were quickly removed, then stripped of the right ventricle, left atrium and the surrounding connective tissues, measuring the actual left ventricular mass with electronic scales.3. echocardiography:before and after the experiment, measuring left ventricular posterior wall thickness and interventricular septum thickness at diastasis.the left ventricular end diastolic and systolic diameter were also measured.Calculating the left ventricular mass (LVM), ejection fraction (EF) and fractional shortening (FS). Measuring E, A peak flow velocity and calculating E/A value.4. Histological staining:After the rats were killed at the end of the experiment, the hearts were removed and fixed in the formaldehyde, then using the heart to make paraffin sections,which used to HE staining and Masson staining.5.Statistical Methods:each group of data used mean±standard deviation, using SPSS13.0software for statistical analysis. Each experiment was repeated at least three times independently. For comparison between multiple groups using ANOVA test, pairwise comparisons using SNK test. P<0.05was indicated statistically significant.Results:1. General inspection results:before the experiment, compared with NC group,the body weight and left ventricular mass measured by ultrasound OB group and F group were increased (P<0.01). After the experiment, compared with the OB group, the body weight and left ventricular mass of F group were significantly lower (P<0.01), left ventricular mass measured by ultrasound was positively correlated with the value measured by electronic scales(r=0.98, P<0.01). Serological examination showed:before the experiment,compared with NC group,total cholesterol, triglycerides, low-density lipoprotein cholesterol of OB group and F froup were increased (P<0.01), after the experiment,, the total cholesterol, triglycerides, low-density lipoprotein cholesterol and free fatty acids were lower of F group than those of OB group(P<0.01).2.Echocardiographic findings:before the experiment, compared with NC group,the ventricular wall thickness and interventricular septum thickness of OB group and F group were significantly increased, E peak, E/A value was significantly lower, EF was significantly reduced(P<0.01). After the experiment, the parameters all above in F group were significantly improved than those of OB group,the difference was statistically significant.3.Histological findings:HE staining showed that compared with NC group, OB group cardiac myocytes were disarrayed, muscle fibers disruption was visible in the cells; F group was significantly better than the OB group, myocardial cells were better arranged, we could see little significant muscle fiber disruption. Masson staining showed that collagen fibers were blue-green,compared with the NC group, myocardial interstitial collagen fibers hyperplasia and derangement were visible in OB group; while the collagen fibers were significantly reduced in F group than those of OB group.Conclusions:Fenofibrate has beneficial effects on preventing myocardial remodeling.By general echocardiography,the effects can be assessed comprehensively and accurately. |
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