Effect Of Coenzyme Q10 Supplementation Research Articles

Effect of coenzyme Q10 supplementation on spermogram parameters, sperm DNA integrity, reproductive hormones and partner pregnancy rate in infertile men with idiopathic oligoasthenospermia

Effect of coenzyme Q10 supplementation on spermogram parameters, sperm DNA integrity, reproductive hormones and partner pregnancy rate in infertile men with idiopathic oligoasthenospermia

The Effect of Coenzyme Q10 Supplementation on Bile Acid Metabolism: Insights from Network Pharmacology, Molecular Docking, and Experimental Validation.

Bile acids play a crucial role in lipid absorption and the regulation of lipid, glucose, and energy homeostasis. Coenzyme Q10 (CoQ10), a lipophilic antioxidant, has been recognized for its positive effects on obesity and related glycolipid metabolic disorders. However, the relationship between CoQ10 and bile acids has not yet been evaluated. This study assesses the impact of CoQ10 treatment on bile acid metabolism in mice on a high-fat diet using Ultra-Performance Liquid Chromatography-tandem Mass Spectrometry. CoQ10 reverses the reduction in serum and colonic total bile acid levels and alters the bile acid profile in mice that are caused by a high-fat diet. Seventeen potential targets of CoQ10 in bile acid metabolism are identified by network pharmacology, with six being central to the mechanism. Molecular docking shows a high binding affinity of CoQ10 to five of these key targets. Further analyses indicate that farnesoid X (FXR) receptor and Takeda G-protein coupled receptor 5 (TGR5) may be crucial targets for CoQ10 to regulate bile acid metabolism and exert beneficial effects. This study sheds light on the impact of CoQ10 in bile acids metabolism and offers a new perspective on the application of CoQ10 in metabolic health.

Statement of Retraction: The effects of coenzyme Q10 supplementation on gene expression related to insulin, lipid and inflammation in patients with polycystic ovary syndrome.

Statement of Retraction: The effects of coenzyme Q10 supplementation on gene expression related to insulin, lipid and inflammation in patients with polycystic ovary syndrome.

The effects of coenzyme Q10 supplementation on biomarkers of exercise-induced muscle damage, physical performance, and oxidative stress: A GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials

PurposeThis study aims to elucidate the dose-dependent effect of coenzyme Q10 supplementation (CoQ10) on exercise-induced muscle damage (EIMD), physical performance, and oxidative stress in adults. MethodsA systematic search was conducted through PubMed, Scopus, and ISI Web of Science databases up to August 2023, focusing on randomized control trials (RCTs) that investigated the effects of CoQ10 supplementation on EIMD recovery, physical performance and oxidative stress mitigation in adults. The weighted mean difference (WMD) and 95% confidence interval (95%CI) were estimated using the random-effects model. ResultsThe meta-analysis incorporated 28 RCTs, encompassing 830 subjects. CoQ10 supplementation significantly decreased creatine kinase (CK) (WMD: -50.64 IU/L; 95%CI: -74.75, -26.53, P<0.001), lactate dehydrogenase (LDH) (WMD: -52.10 IU/L; 95%CI: -74.01, -30.19, P<0.001), myoglobin (Mb) (WMD: -21.77 ng/ml; 95%CI: -32.59, -10.94, P <0.001), and Malondialdehyde (MDA) (WMD: -0.73 μmol/l; 95%CI: -1.26, -0.20, P =0.007) levels. No significant alteration in total antioxidant capacity was observed post-CoQ10 treatment. Each 100 mg/day increase in CoQ10 supplementation was correlated with a significant reduction in CK (MD: -23.07 IU/L, 95%CI: -34.27, -11.86), LDH (WMD: -27.21 IU/L, 95%CI: -28.23, -14.32), Mb (MD: -7.09 ng/ml; 95%CI: -11.35, -2.83) and MDA (WMD: -0.17 μmol/l, 95%CI: -0.29, -0.05) serum levels. Using SMD analysis, "very large" effects on LDH and "moderate" effects on CK and MDA were noted, albeit nonsignificant for other outcomes. ConclusionCoQ10 supplementation may be effective in reducing biomarkers of EIMD and oxidative stress in adults. Nevertheless, given the preponderance of studies conducted in Asia, the generalizability of these findings warrants caution. Further RCTs, particularly in non-Asian populations with large sample sizes and extended supplementation durations, are essential to substantiate these observations.

Effects of coenzyme Q10 supplementation on oxidative stress biomarkers following reperfusion in STEMI patients undergoing primary percutaneous coronary intervention.

It is well-established that oxidative stress is deeply involved in myocardial ischemia-reperfusion injury. Considering the potent antioxidant properties of coenzyme Q10 (CoQ10), we aimed to assess whether CoQ10 supplementation could exert beneficial effects on plasma levels of oxidative stress biomarkers in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPIC). Seventy patients with the first attack of STEMI, eligible for PPCI were randomly assigned to receive either standard treatments plus CoQ10 (400 mg before PPCI and 200 mg twice daily for three days after PPCI) or standard treatments plus placebo. Plasma levels of oxidative stress biomarkers, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), total antioxidant capacity (TAC), and malondialdehyde (MDA) were measured at 6, 24, and 72 hours after completion of PPCI. The changes in plasma levels of the studied biomarkers at 6 and 24 hours after PPCI were similar in the both groups (P values>0.05). This is while at 72 hours, the CoQ10- treated group exhibited significantly higher plasma levels of SOD (P value<0.001), CAT (P value=0.001), and TAC (P value<0.001), along with a lower plasma level of MDA (P value=0.002) compared to the placebo-treated group. The plasma activity of GPX showed no significant difference between the groups at all the study time points (P values>0.05). This study showed that CoQ10 has the potential to modulate the balance between antioxidant and oxidant biomarkers after reperfusion therapy. Our results suggest that CoQ10, through its antioxidant capacity, may help reduce the reperfusion injury in ischemic myocardium.

Effect of Coenzyme Q10 Supplementation on Middle Molecules in Hemodialysis Patients: A Randomized Clinical Trial

Background: Middle molecules, including some cytokines such as IL-6 and TNF-α, parathyroid hormone, etc., are types of uremic toxins having roles in the development of inflammation in hemodialysis patients. Different studies evaluating effects of coenzyme Q10 (CoQ10) on different inflammation markers in hemodialysis patients have controversial results. Moreover, no study determined the effect of CoQ10 on plasma concentration of IL-6, the most powerful predictor of poor outcomes and mortality, in hemodialysis patients. Therefore, a study was designed to examine the effects of CoQ10 supplementation on IL-6, TNF-α, and intact parathyroid hormone (iPTH) in chronic hemodialysis patients.&#x0D; Methods: In this single-blind randomized controlled trial, patients undergoing hemodialysis were randomly assigned to CoQ10 (100 mg/day) or control group. The duration of the study was 12 weeks. The plasma concentrations of IL-6, as the primary outcome, and TNF-α and iPTH, as the secondary outcomes, were measured at baseline and week 12.&#x0D; Results: Of 73 enrolled patients, 68 completed the study. At the end of the study, there were no significant differences in the concentrations of IL-6 (p=0.570), TNF-α (p=0.301), and iPTH (p=0.642) between the two groups. The standardized mean difference (CoQ10 vs. control) was -0.13 (95% CI -0.60; 0.35) for IL-6, -0.25 (95% CI -0.73; 0.22) for TNF-α, and 0.11 (95% CI -0.36; 0.59) for iPTH.&#x0D; Conclusion: This study showed a trivial effect of CoQ10 supplementation on the concentrations of IL-6 and iPTH and a small effect on the level of TNF-α in hemodialysis patients.

The effect of coenzyme Q10 supplementation on liver enzymes: A systematic review and meta-analysis of randomized clinical trials.

Coenzyme Q10 is a potent antioxidant and is necessary for energy production in mitochondria. Clinical data have suggested that coenzyme Q10 (CoQ10) has some beneficial effects on liver function. However, these results are equivocal. This systematic review and meta-analysis aimed to clarify the effect of coenzyme Q10 supplementation on the serum concentration of liver function enzymes. We searched the online databases using relevant keywords up to April 2022. Randomized clinical trials (RCTs) investigating the effect of CoQ10, compared with a control group, on serum concentrations of liver enzymes were included. We found a significant reduction following supplementation with CoQ10 on serum concentrations of alanine aminotransferase (ALT) based on 15 effect sizes from 13 RCTs (weighted mean difference [WMD] = -5.33 IU/L; 95% CI: -10.63, -0.03; p = .04), aspartate aminotransferase (AST) based on 15 effect sizes from 13 RCTs (WMD = -4.91 IU/L; 95% CI: -9.35, -0.47; p = .03) and gamma-glutamyl transferase (GGT) based on eight effect sizes from six RCTs (WMD = -8.07 IU/L; 95% CI: -12.82, -3.32; p = .001; I 2 = 91.6%). However, we found no significant effects of CoQ10 supplementation on alkaline phosphatase concentration (WMD = 1.10 IU/L; 95% CI: -5.98, 8.18; p = .76). CoQ10 supplementation significantly improves circulating ALT, AST, and GGT levels; therefore, it might positively affect liver function. Further high-quality RCTs with more extended intervention periods and larger sample sizes are recommended to confirm our results.

Some Beneficial Effects of Coenzyme Q10 Supplementation on Patients with Chronic Obstructive Pulmonary Disease

Some Beneficial Effects of Coenzyme Q10 Supplementation on Patients with Chronic Obstructive Pulmonary Disease

The Effect of Coenzyme Q10 Supplementation on Insulin Resistance in Overweight/Obese Women with Polycystic Ovary Syndrome

The Effect of Coenzyme Q10 Supplementation on Insulin Resistance in Overweight/Obese Women with Polycystic Ovary Syndrome

Cardioprotective Effects of Coenzyme Q10 Supplementation on Patients with ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

Background: We assessed the potential efficacy of Coenzyme Q10 (CoQ10) in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). Methods: Seventy STEMI patients who presented ≤12 hours after the onset of symptoms and were scheduled for PPCI were randomly assigned to the standard treatments plus CoQ10 or placebo. In the intervention group, CoQ10, as an oral capsule at a dose of 400 mg, was loaded immediately before PPCI and continued at 200 mg twice daily for 28 days. The control group received a matching placebo, similarly. The study endpoints were the proportion of patients with complete myocardial reperfusion, defined as thrombolysis in myocardial infarction (TIMI) flow and myocardial blush grade (MBG) 3 at the end of PPCI, the proportion of patients with complete ST-segment elevation resolution (≥70%) assessed 60 minutes after PPCI, the plasma levels of creatine kinase myocardial band isoenzyme (CK-MB) and troponin I (TnI) at 12, 24, 48, and 72 hours after PPCI, and left ventricular ejection fraction (LVEF) at day 28. Results: The study groups were comparable regarding baseline clinical and procedural characteristics. The proportion of patients with TIMI flow grade 3, MBG 3, and complete ST resolution after completion of PPCI was similar between the groups. Whereas at all-time points after PPCI (12, 24, 48, and 72 hours), the plasma levels of CK-MB and TnI were significantly lower in the CoQ10 group than in the control group. Further, at day 28, CoQ10-treated patients exhibited better LVEF than placebo-treated patients, and the proportion of patients with LVEF less than 50% was lower in the intervention group than in the control group. Conclusion: Our study provided evidence that CoQ10 supplementation might reduce myocardial ischemia-reperfusion injury after PPCI and help to preserve left ventricular function. However, further studies are required to validate these results.

Effects of coenzyme Q10 supplementation on lipid profiles and liver enzymes of nonalcoholic fatty liver disease (NAFLD) patients: A systematic review and meta-analysis of randomized controlled trials.

As an antioxidant, coenzyme Q 10 (CoQ10) has been proposed as a possible treatment for non-alcoholic fatty liver disease (NAFLD). In the present meta-analysis, we aimed to determine the effects of CoQ10 supplementation on lipid profiles and liver enzymes of NAFLD patients. We searched PubMed, Web of Science, Scopus, and Cochrane Library on 21 April 2022 to retrieve randomized controlled trials on NAFLD patients in which CoQ10 was utilized as a treatment. Data were pooled using the random-effects model and weighted mean difference (WMD) was considered as the summary effect size. The analysis of the six included studies indicated an overall non-significant decrease in the lipid profiles (total cholesterol (TC), low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL), and triglyceride (TG)), and liver enzymes (aspartate transaminase (AST), alanine transaminase (ALT), and gamma-glutamyltransferase(GGT))of NAFLD patients who received CoQ10. Sensitivity analysis using "leave-one out" method showed a significant reduction in AST, and GGT after excluding certain studies. Also, subgroup analyses showed significant difference based on CoQ10 dose for TC, AST, and GGT, and also a significant decrease in AST based on the duration of the intervention. No publication bias was found between the studies. Although an overall non-significant decrease was observed in lipid profiles and liver enzymes of NAFLD patients, the results of sensitivity and subgroup analyses showed significant effects of CoQ10 in certain conditions. Further RCTs should be done in light of our findings.

Response to Letter to the Editor from Modarressi and Derakhshan: "Effects of Coenzyme Q10 Supplementation on Lipid Profiles in Adults: A Meta-analysis of Randomized Controlled Trials".

To the Editor, We thank Dr. Modarressi and Dr. Derakhshan (1) for their interest in our recent publication (2). We appreciate their suggestion and respond to their letter here. In our article, we primarily found the beneficial effects of coenzyme Q10 (CoQ10) supplementation on lipid profiles. The main concern of Dr. Modarressi and Dr. Derakhshan was the potential effect of CoQ10 supplementation on cardiovascular diseases (CVDs) by reducing low-density lipoprotein cholesterol (LDL-C). In the Discussion section, we combined the relative risk reduction value obtained by the 2005 Cholesterol Treatment Trialists’ Collaboration data (3) with our results to explore the potential effect of CoQ10 supplementation on coronary mortality by reducing LDL-C. As Dr. Modarressi and Dr. Derakhshan mentioned, the relative risk reduction may be relatively low, but we believe that any significant effect of the nutritional supplements, such as CoQ10, should not be ignored at a population level because it could be used as daily supplement with minor side effects (4) compared with some drugs.

The effects of coenzyme Q10 supplementation on glucose metabolism and lipid profiles in women with polycystic ovary syndrome: A randomized, double-blind, placebo-controlled trial.

The effects of coenzyme Q10 supplementation on glucose metabolism and lipid profiles in women with polycystic ovary syndrome: A randomized, double-blind, placebo-controlled trial.

Expression of concern: Oral carnitine supplementation influences mental health parameters and biomarkers of oxidative stress in women with polycystic ovary syndrome: a randomized, double-blind, placebo-controlled trial and The effects of coenzyme Q10 supplementation on gene expression related to insulin, lipid and inflammation in patients with polycystic ovary syndrome

Expression of concern: Oral carnitine supplementation influences mental health parameters and biomarkers of oxidative stress in women with polycystic ovary syndrome: a randomized, double-blind, placebo-controlled trial and The effects of coenzyme Q10 supplementation on gene expression related to insulin, lipid and inflammation in patients with polycystic ovary syndrome

The Effects of Coenzyme Q10 Supplementation on Oxidative Status and Lipid Profile in Migraine Patients: A Randomized Double-Blinded Controlled Clinical Trial.

Iranian Registry of Clinical Trials Identifier: IRCT201508265670N10.

Homozygous COQ7 mutation: a new cause of potentially treatable distal hereditary motor neuropathy.

Distal hereditary motor neuropathy represents a group of motor inherited neuropathies leading to distal weakness. We report a family of two brothers and a sister affected by distal hereditary motor neuropathy in whom a homozygous variant c.3G>T (p.1Met?) was identified in the COQ7 gene. This gene encodes a protein required for coenzyme Q10 biosynthesis, a component of the respiratory chain in mitochondria. Mutations of COQ7 were previously associated with severe multi-organ disorders characterized by early childhood onset and developmental delay. Using patient blood samples and fibroblasts derived from a skin biopsy, we investigated the pathogenicity of the variant of unknown significance c.3G>T (p.1Met?) in the COQ7 gene and the effect of coenzyme Q10 supplementation in vitro. We showed that this variation leads to a severe decrease in COQ7 protein levels in the patient's fibroblasts, resulting in a decrease in coenzyme Q10 production and in the accumulation of 6-demethoxycoenzyme Q10, the COQ7 substrate. Interestingly, such accumulation was also found in the patient's plasma. Normal coenzyme Q10 and 6-demethoxycoenzyme Q10 levels were restored in vitro by using the coenzyme Q10 precursor 2,4-dihydroxybenzoic acid, thus bypassing the COQ7 requirement. Coenzyme Q10 biosynthesis deficiency is known to impair the mitochondrial respiratory chain. Seahorse experiments showed that the patient's cells mainly rely on glycolysis to maintain sufficient ATP production. Consistently, the replacement of glucose by galactose in the culture medium of these cells reduced their proliferation rate. Interestingly, normal proliferation was restored by coenzyme Q10 supplementation of the culture medium, suggesting a therapeutic avenue for these patients. Altogether, we have identified the first example of recessive distal hereditary motor neuropathy caused by a homozygous variation in the COQ7 gene, which should thus be included in the gene panels used to diagnose peripheral inherited neuropathies. Furthermore, 6-demethoxycoenzyme Q10 accumulation in the blood can be used to confirm the pathogenic nature of the mutation. Finally, supplementation with coenzyme Q10 or derivatives should be considered to prevent the progression of COQ7-related peripheral inherited neuropathy in diagnosed patients.

Effects of Coenzyme Q10 Supplementation on Lipid Profiles in Adults: A Meta-analysis of Randomized Controlled Trials.

Previous meta-analyses have suggested that the effects of coenzyme Q10 (CoQ10) on lipid profiles remain debatable. Additionally, no meta-analysis has explored the optimal intake of CoQ10 for attenuating lipid profiles in adults. This study conducted a meta-analysis to determine the effects of CoQ10 on lipid profiles and assess their dose-response relationships in adults. Databases (Web of Science, PubMed/Medline, Embase, and the Cochrane Library) were systematically searched until August 10, 2022. The random effects model was used to calculate the mean differences (MDs) and 95% CI for changes in circulating lipid profiles. The novel single-stage restricted cubic spline regression model was applied to explore nonlinear dose-response relationships. Fifty randomized controlled trials with a total of 2794 participants were included in the qualitative synthesis. The pooled analysis revealed that CoQ10 supplementation significantly reduced total cholesterol (TC) (MD -5.53 mg/dL; 95% CI -8.40, -2.66; I2 = 70%), low-density lipoprotein cholesterol (LDL-C) (MD -3.03 mg/dL; 95% CI -5.25, -0.81; I2 = 54%), and triglycerides (TGs) (MD -9.06 mg/dL; 95% CI -14.04, -4.08; I2 = 65%) and increased high-density lipoprotein cholesterol (HDL-C) (MD 0.83 mg/dL; 95% CI 0.01, 1.65; I2 = 82%). The dose-response analysis showed an inverse J-shaped nonlinear pattern between CoQ10 supplementation and TC in which 400-500 mg/day CoQ10 largely reduced TC (χ2 = 48.54, P < .01). CoQ10 supplementation decreased the TC, LDL-C, and TG levels, and increased HDL-C levels in adults, and the dosage of 400 to 500 mg/day achieved the greatest effect on TC.

Dose-Response Effect of Coenzyme Q10 Supplementation on Blood Pressure among Patients with Cardiometabolic Disorders: A Grading of Recommendations Assessment, Development, and Evaluation (GRADE)-Assessed Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Previous studies have shown beneficial effects of coenzyme Q10 (CoQ10) supplementation on blood pressure (BP). However, the optimal intake of CoQ10 for BP regulation in patients with cardiometabolic disorders is unknown, and its effect on circulating CoQ10 is also unclear. We aimed to assess the dose-response relation between CoQ10 and BP, and quantify the effect of CoQ10 supplementation on the concentration of circulating CoQ10 by synthesizing available evidence from randomized controlled trials (RCTs). A comprehensive literature search was performed in 3 databases (PubMed/MEDLINE, Embase, and Cochrane Library) to 21 March, 2022. A novel 1-stage restricted cubic spline regression model was used to evaluate the nonlinear dose-response relation between CoQ10 and BP. Twenty-six studies comprising 1831 subjects were included in our meta-analysis. CoQ10 supplementation significantly reduced systolic blood pressure (SBP) (-4.77mmHg, 95% CI: -6.57, -2.97) in patients with cardiometabolic diseases; this reduction was accompanied by a 1.62 (95% CI: 1.26, 1.97) μg/mL elevation of circulating CoQ10 compared with the control group. Subgroup analyses revealed that the effects of reducing SBP were more pronounced in patients with diabetes and dyslipidemia and in studies with longer durations (>12 wk). Importantly, a U-shaped dose-response relation was observed between CoQ10 supplementation and SBP level, with an approximate dose of 100-200mg/d largely reducing SBP (χ2=10.84, Pnonlinearity=0.004). The quality of evidence was rated as moderate, low, and very low for SBP, diastolic blood pressure (DBP), and circulating CoQ10 according to the Grading of Recommendations, Assessment, Development, and Evaluation approach (GRADE), respectively. The current finding demonstrated that the clinically beneficial effects of CoQ10 supplementation may be attributed to the reduction in SBP, and 100-200 mg/d of CoQ10 supplementation may achieve the greatest benefit on SBP in patients with cardiometabolic diseases. This study was registered on PROSPERO as CRD42021252933.

Effects of coenzyme Q10 supplementation on glycemic control: A GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials.

SummaryBackgroundPrevious reviews reported that the effects of CoQ10 on glycemic control were inconsistent. There is no review exploring the optimal intake of CoQ10 for glycemic control. We aimed to investigate the efficacy of CoQ10 on glycemic control and evaluate the dose–response relationship via integrating the existing evidence from randomized control trials (RCTs).MethodsDatabases (PubMed, Embase, and Cochrane Library) were searched to identify RCTs for investigating the efficacy of CoQ10 on fasting glucose, fasting insulin, HbA1c, and HOMA-IR up to March 12, 2022. We performed a meta-analysis on 40 RCTs of CoQ10. Weighted mean difference (WMD) and 95% confidence intervals (CIs) were calculated for net changes. Evidence certainty was assessed using GRADE. Dose-response relationships were evaluated using 1-stage restricted cubic spline regression model. The protocol was registered in PROSPERO (CRD42021252933).FindingsForty studies (n = 2,424 participants) were included in this meta-analysis. CoQ10 significantly reduced fasting glucose (WMD: -5.22 [95% CI: -8.33, -2.11] mg/dl; P <0.001; I2=95.10%), fasting insulin (-1.32 [-2.06, -0.58] μIU/ml; P < 0.001; I2=78.86%), HbA1c (-0.12% [-0.23, -0.01]; P =0.04; I2=49.10%), and HOMA-IR (-0.69 [-1.00, -0.38]; P <0.001; I2=88.80%). The effect of CoQ10 on outcomes was greater in diabetes with lower heterogeneity. A “U” shape dose-response relationship curve revealed that 100-200 mg/day of CoQ10 largely decreased fasting glucose (χ2 = 12.08, Pnonlinearity =0.002), fasting insulin (χ2 = 9.73, Pnonlinearity =0.008), HbA1c (χ2 = 6.00, Pnonlinearity =0.049), HOMA-IR (χ2 = 25.89, Pnonlinearity <0.001).InterpretationCoQ10 supplementation has beneficial effects on glycemic control, especially in diabetes, and 100-200 mg/day of CoQ10 could achieve the greatest benefit, which could provide a basis for the dietary guidelines of CoQ10 in patients with glycemic disorders.FundingThis work was supported by the National Natural Science Foundation of China (No. 82030098, 81872617 and 81730090), Shenzhen Science, Technology, and Innovation Commission (No. JCYJ20180307153228190), CNS Research Fund for DRI, and National innovation and entrepreneurship training program for undergraduate student (No. 202210558161).

Effects of Coenzyme Q10 Supplementation on Oxidative Stress Markers, Inflammatory Markers, Lymphocyte Subpopulations, and Clinical Status in Dogs with Myxomatous Mitral Valve Disease.

Scarce data exist on the effects of coenzyme Q10 (CoQ10) supplementation in dogs with myxomatous mitral valve disease (MMVD). The purpose of this study was to investigate the effect of CoQ10 supplementation on oxidative stress markers (glutathione peroxidase, F2-isoprostanes), markers of inflammation (tumor necrosis factor-α, TNF soluble receptor II, leucocytes, and their subtypes), lymphocyte subpopulations (T helper and cytotoxic T lymphocytes, including activated T lymphocytes, and B lymphocytes), and echocardiographic and clinical parameters in dogs with MMVD. In this randomized, controlled, double-blind, longitudinal study, 43 MMVD dogs in stages ACVIM (American College of Veterinary Internal Medicine classification) B2 and ACVIM C and D (congestive heart failure (CHF)) received water-soluble coenzyme Q10 (100 mg twice daily) or placebo for 3 months, and 12 non-supplemented healthy dogs served as controls. All parameters were measured before and after supplementation in MMVD dogs and once in healthy dogs. CoQ10 supplementation had a positive impact on neutrophil percentage, lymphocyte percentage, and lymphocyte concentration in our cohort of dogs with CHF (ACVIM C and D). Conclusion: CoQ10 as an oral supplement may have benefits in terms of decreasing inflammation in dogs with MMVD and CHF.