Pleiotropic Benefits of Statins in Cardiovascular Diseases

An In Vitro Study on the Antibacterial Activity of Statins Against the Most Common Bacterial Pathogens Causing Respiratory Tract Infections in a Tertiary Care Hospital

Introduction The vast pleiotropic effect of statins has intrigued many researchers to select them as potential candidates against bacterial infections. The role of statins against bacterial pathogens remains debatable. This study was undertaken to evaluate and compare the antibacterial effect of commonly available statins against the most frequently isolated bacterial pathogens causing respiratory tract infections in our tertiary care hospital using sputum as a sample. Materials and methods The study was conducted in the Microbiology Laboratory of our hospital. Drugs including atorvastatin, rosuvastatin, and simvastatin were purchased in pure form from Sigma Aldrich. Dimethylsulfoxide (DMSO) was used as a solvent for all three drugs. The positive controls used were gentamycin and amoxicillin for Gram-negative and Gram-positive bacteria, respectively. Data regarding all the culture and sensitivity results of sputum samples of patients admitted to the Respiratory Intensive Care Unit over the past 12 months were analyzed. The most common bacterial pathogens Staphylococcus aureus, Klebsiella pneumoniae, and Streptococcus pneumoniae isolated from sputum specimens were taken for our study. The antibacterial effect of statins was studied using two methods: the agar cup diffusion method and the broth dilution method. The zone of inhibition and minimum inhibitory concentration of the drugs were calculated and analyzed. Statistical analysis was performed using GraphPad Prism software version 10.2.0. A one-way ANOVA test was used to determine if there was any statistical difference between the different statins and antibiotic groups. An unpaired t-test was used to determine the statistical difference between the statins. Results and discussion For the agar cup diffusion method, our results displayed a lack of antibacterial activity of all three statins atorvastatin, rosuvastatin, and simvastatin against all three bacterial strains Staphylococcus aureus, Klebsiella pneumoniae, and Streptococcus pneumoniae after overnight incubation by agar cup method at concentrations of 3.125 μg/ml, 6.25 μg/ml, 12.5 μg/ml, 25 μg/ml and 50 μg/ml, respectively. The zone of inhibition observed was less than 4 mm (resistant) for all the serial dilutions of atorvastatin, rosuvastatin, and simvastatin. For the broth dilution method, the ANOVA test showed amoxicillin and gentamicin to have high statistically significant microbial growth inhibitory activity (p-value < 0.005) compared to atorvastatin and rosuvastatin. Statistically, though atorvastatin showed significant antimicrobial activity compared to normal saline and rosuvastatin, this was not considered clinically significant as the antimicrobial activity shown by atorvastatin was very negligible compared to the controls used and did not correspond to the serial dilutions of the drug.  Conclusion Atorvastatin, rosuvastatin, and simvastatin lacked antibacterial activity against all three bacterial strains isolated from sputum specimens: Staphylococcus aureus, Klebsiella pneumoniae, and Streptococcus pneumoniae. Hence, the use of statins as an antimicrobial drug for respiratory tract infections has limited applications.

Partial Synthetic PPARƳ Derivative Ameliorates Aorta Injury in Experimental Diabetic Rats Mediated by Activation of miR-126-5p Pi3k/AKT/PDK 1/mTOR Expression

Type 2 diabetes mellitus (T2D) is a world wild health care issue marked by insulin resistance, a risk factor for the metabolic disorder that exaggerates endothelial dysfunction, increasing the risk of cardiovascular complications. Peroxisome proliferator-activated receptor PPAR) agonists have therapeutically mitigated hyperlipidemia and hyperglycemia in T2D patients. Therefore, we aimed to experimentally investigate the efficacy of newly designed synthetic PPARα/Ƴ partial agonists on a High-Fat Diet (HFD)/streptozotocin (STZ)-induced T2D. Female Wistar rats (200 ± 25 g body weight) were divided into four groups. The experimental groups were fed the HFD for three consecutive weeks before STZ injection (45 mg/kg/i.p) to induce T2D. Standard reference PPARƳ agonist pioglitazone and the partial synthetic PPARƳ (PIO; 20 mg/kg/BW, orally) were administered orally for 2 weeks after 72 h of STZ injection. The aorta tissue was isolated for biological ELISA, qRT-PCR, and Western blotting investigations for vascular inflammatory endothelial mediators endothelin-1 (ET-1), intracellular adhesion molecule 1 (ICAM-1), E-selectin, and anti-inflammatory vasoactive intestinal polypeptide (VIP), as well as microRNA126-5p and p-AKT/p-Pi3k/p-PDK-1/p-mTOR, endothelial Nitric Oxide Synthase (eNOS) immunohistochemical staining all are coupled with and histopathological examination. Our results revealed that HFD/STZ-induced T2D increased fasting blood glucose, ET-1, ICAM-1, E-selectin, and VIP levels, while decreasing the expression of both microRNA126-5p and p-AKT/p-Pi3k/p-PDK-1/p-mTOR phosphorylation. In contrast, the partial synthetic PPARƳ derivative evidenced a vascular alteration significantly more than reference PIO via decreasing (ET-1), ICAM-1, E-selectin, and VIP, along with increased expression of microRNA126-5p and p-AKT/p-Pi3k/p-PDK-1/p-mTOR. In conclusion, the partial synthetic PPARƳ derivative significantly affected HFD/STZ-induced T2D with vascular complications in the rat aorta.