A comparative study on the cardioprotective potential of atorvastatin and simvastatin in hyperhomocysteinemic rat hearts

Simvastatin Significantly Reduced Alcohol-Induced Cardiac Damage in Adolescent Mice

Alcohol abuse by adolescents is becoming a serious health concern as they often progress to becoming alcoholics later in life which may lead to heart problems. Chronic alcohol use alters the cardiac function and structure, such as haemodynamic changes, weakening and loss of cardiomyocytes, myocardial fibrosis, and inflammation. Simvastatin is a commonly used drug for the treatment and management of various cardiovascular problems but information on its protective effects against alcohol-induced cardiomyocyte hypertrophy, fibrosis, and inflammation is lacking in the literature. Four-week-old male (n = 5) and female (n = 5) C57BL/6 J mice were assigned to each experimental group: (I) NT-no administration of alcohol or Simvastatin; (II) ALC-2.5 g/Kg/day of 20% alcohol via intraperitoneal injection (i.p.); (III) SIM-5 mg/Kg/day of Simvastatin via oral gavage; (iv) ALC + SIM5-5 mg/Kg/day of Simvastatin via oral gavage followed by 2.5 g/Kg/day of 20% alcohol via i.p.; and (v) ALC + SIM15-15 mg/Kg/day Simvastatin via oral gavage followed by 2.5 g/Kg/day of 20% alcohol via i.p. After the 28-day treatment period, the heart was removed and processed for H&E, Masson's trichrome, or TNF-α immunolabelling. The area and diameter of cardiomyocytes were measured on the H&E-stained sections. The distribution of collagen or TNF-α expression was quantified using the deconvolution tool of ImageJ software. The results confirmed alcohol-induced toxicity on the cardiomyocytes and Simvastatin reduced alcohol-induced cardiomyocyte hypertrophy, fibrosis, and inflammation in both sexes. This study demonstrated that Simvastatin, an FDA approved and easily accessible drug, may be beneficial in lowering the prevalence of alcohol-induced cardiovascular diseases (especially in adolescents) which will have a huge financial implication on health systems worldwide.

Inhibition of Rho-kinase is involved in the therapeutic effects of atorvastatin in heart ischemia/reperfusion

The aim of the present study was to investigate the effects of atorvastatin against heart ischemia/reperfusion (I/R) injury and its potential underlying mechanism. Rats were allocated into the following groups: Sham, I/R, atorvastatin (10 mg/kg daily), fasudil (10 mg/kg daily) and atorvastatin + fasudil in combination. Drugs were administered for 2 weeks prior to I/R injury. I/R was established by ligating the left anterior descending branch (LAD) for 30 min and releasing the ligature for 180 min. The I/R group was found to have increased myocardial infarct size, cardiomyocyte apoptosis, levels of plasma interleukin (IL)-6 and tumor necrosis factor (TNF)-α, superoxide dismutase (SOD) activity, malondialdehyde (MDA) levels and Rho-kinase activity compared with the other treatment groups (P<0.05). Moreover, pretreatment with atorvastatin significantly attenuated Rho-kinase activity, myocardial infarct size, cardiomyocyte apoptosis, levels of plasma IL-6 and TNF-α, SOD activity and MDA levels, and upregulated nitric oxide production. It was also indicated that the specific Rho-kinase inhibitor, fasudil, had the same effects as atorvastatin in I/R. Therefore, the present results suggested atorvastatin may lead to cardiovascular protection, which may be mediated by Rho-kinase inhibition in heart I/R injury.

Atherogenic Impact of Homocysteine: Can HMG-CoA Reductase Inhibitors Additionally Influence Hyperhomocysteinaemia?

The strong association among the risk of coronary artery diseases (CAD), high levels of LDL-C and low levels of HDLC is well established. Hyperhomocysteinaemia (HHcy) is an independent risk factor for cardiovascular disease (CVD) and causes endothelial dysfunction, a hallmark of atherosclerosis. In this study, we ascertained the influence of statins on the atherogenic index, as an indicator and a significant adjunct for predicting atherosclerosis in hyperhomocysteinaemic male Wistar albino rats. For 4 weeks, the animals were fed with one of the following diets (Mucedola SRL., Milan, Italy): standard rodent chow; a diet enriched in methionine with no deficiency in B vitamins or a diet enriched in methio-nine and deficient in B vitamins. The animals were simultaneously exposed to a pharmacology treatment with atorvastatin at dose of 3 mg/kg/day i.p. or simvastatin, at dose of 5 mg/kg/day i.p. We measured weight gain, food intake, and FER and determined the concentrations of biochemical parameters of dyslipidaemia (TC, TGs, LDL-C, VLDL-C, and HDL-C), AI, and CRR. A histopathological examination was conducted on portions of the right and left liver lobes from each animal. A connection between Hhcy and dyslipidaemia was indicated by the findings of biochemical and histological analyses, suggesting that Hhcy was a pro-atherogenic state. An improvement in the lipid profile along with a decrease in the atherogenic index by statins suggests that atorvastatin and simvastatin could be useful antiatherogenic agents, with protective activities during hyperhomocysteinaemia.

Effects of Simvastatin on Fetal Cardiac Impairment in the Diaphragmatic Experimental Hernia Model

BACKGROUND

Statins and sildenafil have been shown to exert beneficial effects in cardiac injury. We hypothesized that antenatal maternal administration of simvastatin and/or sildenafil might also promote benefits in cardiac remodeling of congenital diaphragmatic hernia (CDH). Therefore, we performed micro-CT image analysis and histology of the heart after antennal treatment in experimental nitrofen-induced CDH.

METHODS

At 9.5 days post conception (dpc), pregnant rats were exposed to nitrofen. At 16 and 20 dpc fetuses were treated with simvastatin and/or sildenafil. At 21 dpc postmortem micro-CT and autopsy were performed.

RESULTS

All nitrofen-treated fetuses had a lower birth weight compared to controls; in the simvastatin-treated group, a significant improvement in CDH was noted. Impairment of the lung and liver was also noted in CDH. Compared to controls, CDH rats showed lower ventricular mass, with greater left ventricular thickness; simvastatin decreased the ventricular mass and improved wall thickness. CDH rats exhibited myocardial hypotrophy, severe vascular depression in the left ventricle, and intense interstitial edema compared to controls and nitrofen-exposed animals without CDH. In CDH, the cardiac morphology appeared deformed with left ventricular wall verticalization. Simvastatin improved cardiac myocyte appearance and heart morphology.

CONCLUSION

The potential to treat CDH with antenatal simvastatin may improve the management of this malformation.

Effects of atorvastatin and simvastatin on oxidative stress in diet-induced hyperhomocysteinemia in Wistar albino rats: a comparative study

Considering the well-known antioxidant properties of statins, it seems important to assess their impact on major markers of oxidative stress (superoxide anion radical, nitric oxide, and index of lipid peroxidation) to compare the antioxidative potentials of atorvastatin and simvastatin during the different degrees of hyperhomocysteinemia (HHcy) in rats. This study was conducted on adult male Wistar albino rats (n = 90; 4 weeks old; 100 ± 15 g body mass) in which HHcy was achieved by dietary manipulation. For 4 weeks, the animals were fed with one of the following diets: standard rodent chow, diet enriched in methionine with no deficiency in B vitamins (folic acid, B6, and B12), or diet enriched in methionine and deficient in B vitamins (folic acid, B6, and B12). At the same time, animals were treated with atorvastatin at doses of 3 mg/kg/day i.p. or simvastatin at doses of 5 mg/kg/day i.p. Levels of superoxide anion radical and TBARS were significantly decreased by administration of simvastatin in normal and high-homocysteine (Hcy) groups (p < 0.05). At 4 weeks after feeding with purified diets, the concentrations of the GSH, CAT, and SOD antioxidants were significantly affected among all groups (p < 0.05). Our results indicated that statin therapy had variable effects on the redox status in hyperhomocysteinemic rats, and simvastatin demonstrated stronger antioxidant effects than did atorvastatin.