Q10 supplementation effects on cardiac enzyme CK-MB and troponin in patients undergoing coronary artery bypass graft: a randomized, double-blinded, placebo-controlled clinical trial

The physiological insight of Coenzyme-Q10 administration in preventing the incidence of reperfusion arrhythmia among patients undergoing coronary artery bypass grafting surgery

Reperfusion arrhythmia following cardiac surgery has long been studied as part of myocardial damage. Reperfusion injury is thought to be exacerbated by oxygen-free radicals, whereas arrhythmogenic oscillations in membrane potential are mediated by reactive oxygen. Coenzyme Q10 is a lipid-soluble antioxidant that inhibits lipid peroxidation in biological membranes and supplies ATP cell synthesis, required as the organism's primary energy source. This process explains how Coenzyme Q10 helps stabilize membranes and avoids critical metabolite depletion that may relate to reperfusion arrhythmia. There is a reduction of iatrogenic Coenzyme Q10 after coronary artery bypass surgery (CABG). On the other hand, there is an increased inflammatory process and cellular demand post CABG procedure. It leads to ischemia that can be manifested as arrhythmia. Reperfusion arrhythmia was less common in patients who took Coenzyme Q10. These findings suggest that Coenzyme Q10 supplementation might help patients with heart surgery avoid reperfusion arrhythmia. However, a higher-quality randomized controlled study is needed to determine the effect of Coenzyme Q10 in preventing reperfusion arrhythmia in cardiac surgery patients.

The effects of N-acetylcysteine on recovery biomarkers: A systematic review and meta-analysis of controlled trials

N-acetylcysteine (NAC) is one of the antioxidant supplements which is thought to improve recovery. Existing studies regarding NAC and recovery presented conflicting results. This systematic review and meta-analysis evaluated the existing trials and determined the efficacy of acute and chronic NAC administration on recovery biomarkers. PubMed, Web of Science, and Scopus were searched up to July 2021. The random effects or fixed effects model was applied in the meta-analysis. Sensitivity and subgroup analyses were performed. In case of the presence of publication bias, standard methods were applied. The meta-analysis comprised 37 papers (1,388 participants). All included studies were in English language. Acute NAC administration indicated no significant effects on lactate, pH, VO₂ , and CPK-MB ([SMD = -0.06 mmol/L; 95% CI: -0.40, 0.28; p = .714], [SMD = 0.17; 95% CI: -0.28, 0.62; p = .454], [SMD = -0.11 L/min; 95% CI: -0.63, 0.41; p = .686], and [SMD = -0.19 units/L; 95% CI: -0.62, 0.24; p = .395]). Additionally, no evidence of significant influence of chronic NAC administration on lactate, pH, VO₂ , and CK was revealed ([SMD = 0.01 mmol/L; 95% CI: -0.25, 0.27; p = .950], [SMD = -0.51; 95% CI: -1.73, 0.70; p = .424], [SMD = -0.18 L/min; 95% CI: -0.56, 0.20; p = .361], and [SMD = -0.04 units/L; 95% CI: -0.36, 0.29; p = .821]). No considerable effect of NAC on recovery was found. PRACTICAL APPLICATIONS: Previous studies on the influence of NAC administration on recovery biomarkers have presented conflicting results. This systematic review and meta-analysis offers a broad range of detailed information on the influence of chronic and acute NAC supplementation outcomes regarding recovery biomarkers. Overall, the results support that NAC supplementation may not be effective in improving recovery biomarkers. However, subgroup analyses based on NAC dosage indicated the meaningful effect of NAC on CK-MB at the dosage of ≥100 mg/kg.

Combating Ischemia-Reperfusion Injury with Micronutrients and Natural Compounds during Solid Organ Transplantation: Data of Clinical Trials and Lessons of Preclinical Findings

Although extended donor criteria grafts bear a higher risk of complications such as graft dysfunction, the exceeding demand requires to extent the pool of potential donors. The risk of complications is highly associated with ischemia-reperfusion injury, a condition characterized by high loads of oxidative stress exceeding antioxidative defense mechanisms. The antioxidative properties, along with other beneficial effects like anti-inflammatory, antiapoptotic or antiarrhythmic effects of several micronutrients and natural compounds, have recently emerged increasing research interest resulting in various preclinical and clinical studies. Preclinical studies reported about ameliorated oxidative stress and inflammatory status, resulting in improved graft survival. Although the majority of clinical studies confirmed these results, reporting about improved recovery and superior organ function, others failed to do so. Yet, only a limited number of micronutrients and natural compounds have been investigated in a (large) clinical trial. Despite some ambiguous clinical results and modest clinical data availability, the vast majority of convincing animal and in vitro data, along with low cost and easy availability, encourage the conductance of future clinical trials. These should implement insights gained from animal data.

Ubiquinol supplementation in elderly patients undergoing aortic valve replacement: biochemical and clinical aspects

Epidemiological data show a rise in the mean age of patients affected by heart disease undergoing cardiac surgery. Senescent myocardium reduces the tolerance to ischemic stress and there are indications about age-associated deficit in post-operative cardiac performance. Coenzyme Q10 (CoQ10), and more specifically its reduced form ubiquinol (QH), improve several conditions related to bioenergetic deficit or increased exposure to oxidative stress. This trial (Eudra-CT 2009-015826-13) evaluated the clinical and biochemical effects of ubiquinol in 50 elderly patients affected by severe aortic stenosis undergoing aortic valve replacement and randomized to either placebo or 400 mg/day ubiquinol from 7 days before to 5 days after surgery. Plasma and cardiac tissue CoQ10 levels and oxidative status, circulating troponin I, CK-MB (primary endpoints), IL-6 and S100B were assessed. Moreover, main cardiac adverse effects, NYHA class, contractility and myocardial hypertrophy (secondary endpoints) were evaluated during a 6-month follow-up visit. Ubiquinol treatment counteracted the post-operative plasma CoQ10 decline (p<0.0001) and oxidation (p=0.038) and curbed the post-operative increase in troponin I (QH, 1.90 [1.47-2.48] ng/dL; placebo, 4.03 [2.45-6.63] ng/dL; p=0.007) related to cardiac surgery. Moreover, ubiquinol prevented the adverse outcomes that might have been associated with defective left ventricular ejection fraction recovery in elderly patients.

The Effect of Vitamin C Supplementation on Cardiac Enzymes After Coronary Artery Bypass Graft: A Double-blind Randomized Control Trial

Background:

Coronary artery bypass graft (CABG) is associated with oxidative stress and tissue damage. Vitamin C, as an antioxidant agent, has an important role in attenuating the oxidative stress damage and might have cardio-protective effects after CABG. We aimed to evaluate the probable roles of vitamin C supplementation in cardiac biomarkers after CABG.

Methods::

In this randomized control trial, 122 patients undergoing CABG were randomly assigned to the intervention (n=54) and control group (n=68) and received vitamin C (2 g intravenously) or placebo, respectively. The surgical methods of the patients in the two groups were identical. The primary efficacy endpoint of this trial is the difference in the levels of CK-MB, Troponin and Total Antioxidant Capacity (TAC) were measured at study entry and 24 hrs after surgery between the two groups.

Results::

The two groups were not significantly different in terms of basic variables. Within-group comparison showed significant rises in the level of troponin (P < 0.001) and CK-MB (P < 0.001) over time. However, between-group comparison showed no significant difference between the two groups in terms of CK-MB (P=0.826) and troponin (P=0.821). As a whole, the correlation between cardiac enzymes and surgical characteristic was not seen.

Conclusion::

The results showed that pretreatment with vitamin C could not reduce cardiac marker following CABG. After the intervention, TAC did not differ between and within the intervention and the control groups. Pretreatment with vitamin C as an antioxidant agent could not reduce ischemicreperfusion resulting in CABG.

Effect of flaxseed oil supplementation on anthropometric and metabolic indices in patients with coronary artery disease: A double-blinded randomized controlled trial

Introduction: It has been established that omega 3 fatty acids have cardio-protective effects through modulation of cardiometabolic risk factors via multiple mechanisms. The aim of this study was to investigate the effects of flaxseed oil on anthropometric indices and lipid profile in patients with coronary artery disease (CAD). Methods: A randomized, double-blind, placebo-controlled trial was performed in 44 patients with CAD. The subjects were randomly assigned to receive either 200 ml of 1.5% fat milk supplemented by 5 g of flaxseed oil (containing 2.5 g α-Linolenic acid) as intervention or 200 ml of 1.5% fat milk as placebo group for 10 consecutive weeks. Anthropometric indices and lipid profile were assessed at baseline and post-intervention. Results: The results indicated that supplementation with flaxseed oil had no impact on anthropometric indices. Weight, body mass index, waist circumference and hip circumference decreased statistically significant within groups, but not between groups. At the end of the intervention, diastolic blood pressure (DBP) decreased significantly (P = 0.022) in the intervention group. Moreover, the triglyceride (TG) level decreased significantly in the intervention group from 173.45 (49.09) to 139.33 (34.26) (P < 0.001). Other lipid profile indices including total cholesterol, low density lipoprotein and high density lipoprotein did not differ significantly within and between groups. Conclusion: We observed that supplementation of flaxseed oil improved TG and DBP but had no effect on other lipid profiles and anthropometric indices in patients with CAD.

Chronic hypoxia–induced Cirbp hypermethylation attenuates hypothermic cardioprotection via down-regulation of ubiquinone biosynthesis

Therapeutic hypothermia is commonly used during cardiopulmonary bypass (CPB) to protect the heart against myocardial injury in cardiac surgery. Patients who suffer from chronic hypoxia (CH), such as those with certain heart or lung conditions, are at high risk of severe myocardial injury after cardiac surgery, but the underlying mechanisms are unknown. This study tested whether CH attenuates hypothermic cardioprotection during CPB. Using a rat model of CPB, we found that hypothermic cardioprotection was impaired in CH rats but was preserved in normoxic rats. Cardiac proteomes showed that cold-inducible RNA binding protein (CIRBP) was significantly (P = 0.03) decreased in CH rats during CPB. Methylation analysis of neonatal rat cardiomyocytes under CH and myocardium specimens from patients with CH showed that CH induced hypermethylation of the Cirbp promoter region, resulting in its depression and failure to respond to cold stress. Cirbp-knockout rats showed attenuated hypothermic cardioprotection, whereas Cirbp-transgenic rats showed an enhanced response. Proteomics analysis revealed that the cardiac ubiquinone biosynthesis pathway was down-regulated during CPB in Cirbp-knockout rats, resulting in a significantly (P = 0.01) decreased concentration of ubiquinone (CoQ10). Consequently, cardiac oxidative stress was aggravated and adenosine 5′-triphosphate production was impaired, leading to increased myocardial injury during CPB. CoQ10-supplemented cardioplegic solution improved cardioprotection in rats exposed to CH, but its effect was limited in normoxic rats. Our study suggests that an individualized cardioprotection strategy should be used to fully compensate for the consequences of epigenetic modification of Cirbp in patients with CH who require therapeutic hypothermia.

Health outcomes of on-pump pulmonary valve replacement surgery with and without cardioplegic arrest: a comparison study in tetralogy of Fallot subjects

BACKGROUND

Tetralogy of Fallot is one of the most common congenital heart diseases in which four important cardiovascular defects. Pulmonary valve regurgitation (PVR) after TOF surgery is one of the indications for its replacement which is carried out with two surgical methods, on-pump surgery with and without cardiac arrest.

OBJECTIVE

The aim of this study was to compare the results of the pulmonary valve replacement surgery with and without cardiac arrest.

MATERIALS AND METHODS

In this retrospective study, the information of medical records of all patients with TOF that candidates for pulmonary valve replacement from 2008 to 2014, whom treated in Kermanshah's Imam Ali cardiac hospital, Kermanshah. Iran and Shaheed Rajaei Heart Center in Tehran with the two common surgical procedure, with and without cardiac arrest, were studied. With matching for age and sex, 33 patients enrolled in this study, 16 patients underwent surgery with the arrest (in Kermanshah's Imam Ali cardiac hospital, Kermanshah. Iran) and 17 subjects operated without cardiac arrest (on pump beating heart in Shaheed Rajaei Heart Center in Tehran).

RESULTS

The results of this study showed that patients operated using without cardiac arrest compared to the with cardiac arrest, were superior in the hospital and ICU stay, bleeding until 24 hours after surgery, intubated time, inotropic support, and duration of surgery (P<0.05). Also, hemoglobin, blood pressure, ejection fraction (EF), and tricuspid regurgitation after surgery were statistically significant difference between two groups (P<0.05).

CONCLUSION

The results of this study showed that although during the (on pump beating heart without aortic cross clamp) without cardiac arrest surgery method some problems may be created for the surgeon, nevertheless, patients after without arrested procedure have a better outcomes compared to the cardiac arrest method.

New insights on atherosclerosis: A cross-talk between endocannabinoid systems with gut microbiota

The incidence of atherosclerosis is increasing rapidly all over the world. Inflammatory processes have outstanding role in coronary artery disease (CAD) etiology and other atherosclerosis manifestations. Recently attentions have been increased about gut microbiota in many fields of medicine especially in inflammatory diseases like atherosclerosis. Ineffectiveness in gut barrier functions and subsequent metabolic endotoxemia (caused by rise in plasma lipopolysaccharide levels) is associated with low-grade chronic inflammation i.e. a recognized feature of atherosclerosis. Furthermore, the role of trimethylamine-N-oxide (TMAO), a gut bacterial metabolite has been suggested in atherosclerosis development. On the other hand, the effectiveness of gut microbiota modulation that results in TMAO reduction has been investigated. Moreover, considerable evidence supports a role for the endocannabinoid system (ECS) in atherosclerosis pathology which affects gut microbiota, but their effects on atherosclerosis are controversial. Therefore, we presented some evidence about the relationship between gut microbiota and ECS in atherosclerosis. We also presented evidences that gut microbiota modulation by pre/probiotics can have significant influence on the ECS.

Ubiquinol (Reduced Coenzyme Q10) and Cellular Oxygen Consumption in Patients Undergoing Coronary Artery Bypass Grafting

Ubiquinol is a fundamental component of cellular metabolism. Low ubiquinol levels have been associated with mortality. This was a substudy of a randomized trial in patients undergoing coronary artery bypass grafting. We drew blood before and after surgery. Ubiquinol or placebo was added to peripheral blood mononuclear cells for oxygen consumption (OCR) measurements. In vivo ubiquinol levels were lower postsurgery compared to presurgery (0.16 μmol/L [quartiles: 0.02-0.39], P = .01), although the difference disappeared when adjusting for hemoglobin levels (P = .30). There was no difference in presurgical basal (1.0 mL/min/mg [95% confidence interval [CI]: -0.9 to 2.2], P = .08) and maximal (0.5 mL/min/mg [95% CI: -4.3 to 7.3], P = .56) OCR in cells receiving ubiquinol or placebo. There was a difference in postsurgical basal (1.1 mL/min/mg [95% CI: 0.9-1.6], P < .001) and maximal (4.2 mL/min/mg [95% CI: 0.3-7.0], P = .01) OCR between the groups. We found no association between ubiquinol and OCR levels (all P > .05).

Heat shock protein 70 protects cardiomyocytes through suppressing SUMOylation and nucleus translocation of phosphorylated eukaryotic elongation factor 2 during myocardial ischemia and reperfusion

Myocardial ischemia and reperfusion (MIR) results in cardiomyocyte apoptosis with severe outcomes, which blocks cardiac tissue recovering from myocardial ischemia diseases. Heat shock protein 70 (HSP70) is one of protective molecule chaperones which could regulate the nucleus translocation of other proteins. In addition, eukaryotic elongation factor 2 (eEF2), which modulates protein translation process, is vital to the recovery of heart during MIR. However, the relationship between HSP70 and eEF2 and its effects on MIR are unclear. The expression and relationship between HSP70 and eEF2 is confirmed by western blot, immunoprecipitation in vitro using cardiomyocyte cell line H9c2 and in vivo rat MIR model. The further investigation was conducted in H9c2 cells with detection for cell-cycle and apoptosis. It is revealed that eEF2 interacted and be regulated by HSP70, which kept eEF2 as dephosphorylated status and preserved the function of eEF2 during MIR. In addition, HSP70 suppressed the nucleus translocation of phosphorylated eEF2, which inhibited cardiomyocyte apoptosis during myocardial reperfusion stage. Furthermore, HSP70 also interacted with C-terminal fragment of eEF2, which could reverse the nucleus translocation and cardiomyocyte apoptosis caused by N-terminal fragment of eEF2. HSP70 draw on advantage and avoid defect of MIR through regulating phosphorylation and nucleus translocation of eEF2.