Protective Effect of Rutin Trihydrate Against Dose-Dependent, Cisplatin-Induced Cardiac Toxicity in Isolated Perfused Rat's Heart.

Background Cisplatin is a common anticancer drug with potential cardiac and renal toxicities. Rutin, a natural compound present in various medicinal plants, has been shown to protect against chemotherapy-induced toxicities. In this study, we explored the protective effect of rutin against the dose-dependent cardiotoxic effects of cisplatin such as perfusion pressure, histopathologic effect on the myocardium, and oxidative stress in isolated perfused rat hearts. Methodology The cardiotoxic effects of cisplatin were studied at three dosages (1, 7, and 14 mg/L) in isolated perfused rat hearts. The dose-dependent, cisplatin-induced toxic effects on left ventricular pressure (LVP), heart rate (HR), dp/dt (maximum), dp/dt (minimum), perfusion pressure, pressure-time index, contractility index, and duration of diastole were assessed. The effects of cisplatin were measured one minute before perfusion of cisplatin and 60 minutes after perfusion of the isolated rat hearts. Results Cisplatin (1-14 mg/L) caused a significant (p < 0.05) dose-dependent reduction in LVP. The percentage LVP values reduced from 94 ± 9 (control untreated hearts) to 70 ± 6, 69 ± 5, and 65 ± 4 in hearts treated with 1, 7, and 14 mg/L of cisplatin, respectively. Similarly, cisplatin at similar doses caused a marked reduction in the values of dp/dt (maximum), dp/dt (minimum), and pressure-time index in isolated rat hearts. The respective percentage values of these parameters compared to those of untreated hearts were significantly reduced from 101 ± 7 to 72 ± 5, 92 ± 8 to 69 ± 4, and 92 ± 12 to 57 ± 7 in hearts treated with 14 mg/L of cisplatin. Perfusion of hearts with rutin trihydrate (1 µM/L) 10 minutes before administration of cisplatin and throughout the experiment attenuated the detrimental effects of cisplatin on cardiac functions in isolated rat hearts (p < 0.05). In addition, cisplatin-induced degeneration and necrosis of cardiac muscle cells reduced with the concurrent administration of rutin and restored normal heart histology. Moreover, cisplatin-induced reduction in glutathione and increased level of malondialdehyde in the myocardium was reversed by concurrent administration of rutin in isolated rat hearts. Conclusions Cisplatin produced a dose-dependent impairment of several parameters of cardiac function such as LVP, contractility index, and pressure-time index. It caused histopathological alterations in isolated rat hearts. These harmful effects of cisplatin were suppressed by rutin trihydrate, suggesting the potential protective effects of rutin against cisplatin-induced cardiotoxicity. Rutin trihydrate also improved the reduced glutathione contents and suppressed the malondialdehyde contents in the cardiac tissue of isolated rat hearts, suggesting that the observed beneficial effects of rutin trihydrate in this study could be related to its antioxidant properties.

Relationship between work-related ocular events, facial injuries and associated factors amongst dental professionals during COVID-19.

BACKGROUND: In dental settings, COVID-19 can be transmitted directly from patients to dentists through small droplets, saliva splashes, blood, and other body fluids liberated as a result of dental procedures. OBJECTIVE: To determine the prevalence of ocular and facial injuries in dental professionals and to investigate factors in dental practice contributing to ocular injuries. METHODS: An analytical cross-sectional study was performed in public and private sector universities. The study had 301 participants including final year undergraduate students, interns, postgraduate trainees, general practitioners, and dental specialists. Data were gathered online using Google forms. Information on sociodemographic, practice details, history of ocular and facial encounters during the clinical experience, and protective measures adopted by the dentists were collected. Means and standard deviations were calculated for continuous variables whereas frequencies and percentages were calculated for categorical variables. A Chi-square test was applied for association between variables. RESULTS: Ocular events and facial injuries occurred more in females 204 (67.8%) than in males 97(32.2%). Final year students reported more incidence of ocular encounters than specialists (40.9%, 3.3%). Dentists working in the government sector underwent more ocular encounters than those in private sectors 185(61.4%) and 96 (31.8%). Majority of participants reported that scaling was the procedure in which dentists experienced an ocular event. A significant association was found between ocular events, qualification, years of experience in clinical practice, number of patients treated per day, improper posture, and proper armamentarium (p < 0.05). However, no association was found between ocular events, gender, working sector, and dental procedures. CONCLUSION: Occurrence of ocular injuries were high compared to facial injuries and these outcomes were dependent on dental expertise and experiences. Appropriate measures should be adopted to minimize the risk of disease transmission and COVID-19 through the eyes among practicing dentists.

The protective effect of losartan against sorafenib induced cardiotoxicity: Ex-vivo isolated heart and metabolites profiling studies in rat.

Sorafenib, a tyrosine kinase inhibitor that is used in the treatment of hepatocellular and renal cell carcinoma, was reported to induce cardiotoxicity. This study aimed to investigate the potential cardioprotective effect of losartan against sorafenib-induced cardiotoxicity in rat. Sorafenib significantly reduced the left ventricular pressure, heart rate dp/dt max & dp/dt min (indexes of myocardial contractility and relaxation; respectively), and prolonged both the systolic and diastolic periods. Coadminstration of losartan significantly reversed the effects of sorafenib on heart rate, dp/dt max and dp/dt min. In addition, there was a tendency for losartan to reverse sorafenib reduction in left ventricular pressure and perfusion pressure but it did not reach statistical significance. A GC-MS non-targeted based metabolites profiling of rat plasma revealed elevated metaboites, including urea and fatty acids levels, associated with sorafenib induced cardiotoxicity. However, only glycine and lactic acid were statistically significant. Interestingly, losartan co-administration with sorafenib restored these changes, and resulted in a significantly reduced glycine, urea and some fatty acids levels namely; Cis-vaccenic acid, oleic acid, stearic acid and undecanoic acid. In addition, based on histology results, losartan coadminitration almost obviated sorafenib-induced changes in cardiac tissues. The study suggests that losartan has the potential to exert a protective effect against sorafenib-induced cardiotoxicity.

Cardioprotective Effect of Olive Oil Against Ischemia Reperfusion-induced Cardiac Arrhythmia in Isolated Diabetic Rat Heart.

Background Olive oil is rich in monounsaturated fatty acids and has been reported for a variety of beneficial cardiovascular effects, including blood pressure lowering, anti-platelet, anti-diabetic, and anti-inflammatory effects. Diabetes is a major risk factor for cardiac dysfunctions, and olive oil prevents diabetes-induced adverse myocardial remodeling. Objective The study aimed to evaluate the effects of olive oil against streptozotocin-induced cardiac dysfunction in animal models of diabetes and ischemia and reperfusion (I/R)-induced cardiac arrhythmias. Methods Diabetes was induced in male rats with a single intraperitoneal injection of streptozotocin (60 mg/kg i.p), rats were treated for five, 15, or 56 days with olive oil (1 ml/kg p.o). Control animals received saline. Blood glucose and body weight were monitored every two weeks. At the end of the treatment, rats were sacrificed and hearts were isolated for mounting on Langedorff's apparatus. The effect of olive oil on oxidative stress and histopathological changes in the cardiac tissues were studied. Results The initial blood glucose and body weight were not significantly different in the control and olive-treated animals. Streptozotocin (60 mg/kg i.p) caused a significant increase in the blood glucose of animals as compared to saline-treated animals. The control, saline-treated diabetic animals exhibited a 100% incidence of I/R-induced ventricular fibrillation, which was reduced to 0% with olive oil treatment. The protective effects of olive oil were evident after 15 and 56 days of treatment. Diltiazem, a calcium channel blocker (1 µm/L) showed similar results and protected the I/R-induced cardiac disorders. The cardiac tissues isolated from diabetic rats exhibited marked pathological changes in the cardiomyocytes, including decreased glutathione (GSH) and increased oxidative stress (malondialdehyde; MDA). Pretreatment of animals with olive oil (1 ml/kg p.o) increased GSH and decreased MDA levels. Olive oil also improved the diabetic-induced histopathological changes in the cardiomyocytes. Conclusion Olive oil possesses cardiac protective properties against I/R-induced cardiac arrhythmias in rats. It attenuated oxidative stress and diabetes-induced histopathological changes in cardiac tissues. The observed cardiac protectiveness of olive oil in the present investigation may be related to its antioxidant potential.

Protective effect of fenofibrate against ischemia-/reperfusion-induced cardiac arrhythmias in isolated rat hearts.

Fenofibrate is a peroxisome proliferator-activated receptor (PPAR)-α activator that lowers triglycerides and influences cytochrome P-450 (CYP-450) epoxygenase-dependent arachidonic acid (AA) metabolism. CYP-450 epoxygenase metabolizes AA to epoxyeicosatrienoic acids (EETs). EETs have coronary dilating and cardiac and renal protective properties. Fibrates possess similar properties due to their CYP-450 epoxygenase-inducing properties that lead to increase in endogenous EET production. In the current investigations, fenofibrate (100 mg/kg, orally) for 2 weeks decreased ischemia-/reperfusion (I/R)-induced premature ventricular contractions (PVCs), ventricular tachycardia (VT), and ventricular fibrillation (VF) in the isolated rat hearts. Fenofibrate caused marked inhibition of the reperfusion-induced cardiac arrhythmias. The incidence of reperfusion-induced VF decreased from 80% in the control vehicle-treated animals to 33% in the fenofibrate-treated animals (P < 0.001). PVCs were also significantly (P < 0.01) decreased from 223.2 ± 51 in control vehicle-treated animals to 136.8 ± 22 in fenofibrate-treated animals. Total duration of reperfusion-induced VT decreased from 29.2 ± 6.3 s in control, vehicle-treated animals to 4.8 ± 1.3 s in fenofibrate-treated animals, P < 0.001. Heart rate and perfusion pressure were not significantly affected by fenofibrate pretreatment. Diltiazem, a clinically used anti-arrhythmic agent, produced complete protection against I/R-induced cardiac arrhythmias in this model reducing the incidence of VF from 80% in control, vehicle-treated animals to 10% in diltiazem-treated hearts. These findings indicate that fenofibrate suppresses arrhythmias in isolated rat hearts subjected to I/R-induced injury.