Serum concentration of lipoprotein(a) decreases on treatment with hydrosoluble coenzyme Q10 in patients with coronary artery disease: discovery of a new role

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

CONTEXT

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.

OBJECTIVE

This study conducted a meta-analysis to determine the effects of CoQ10 on lipid profiles and assess their dose-response relationships in adults.

METHODS

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.

RESULTS

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).

CONCLUSION

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.

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

BACKGROUND

Previous 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).

METHODS

Databases (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).

FINDINGS

Forty 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%), HbA_1c (-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 (χ ² = 12.08, P _nonlinearity =0.002), fasting insulin (χ ² = 9.73, P _nonlinearity =0.008), HbA_1c (χ ² = 6.00, P _nonlinearity =0.049), HOMA-IR (χ ² = 25.89, P _nonlinearity <0.001).

INTERPRETATION

CoQ10 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.

FUNDING

This 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 Biomarkers of Oxidative Stress in Adults: A GRADE-Assessed Systematic Review and Updated Meta-Analysis of Randomized Controlled Trials

Evidence shows that exogenous CoQ10 supplementation may potentially attenuate oxidative stress status. However, its effective dose and evidence certainty require further evaluation in the general population via more updated randomized controlled trials (RCTs). Databases (PubMed, Embase and Cochrane Library) were searched up to 30 March 2022. Evidence certainty was assessed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. Thirty-four RCTs containing 2012 participants were included in this review. Pooled effects of significant increase in total antioxidant capacity (TAC) (standardized mean difference: 1.83, 95%CI: [1.07, 2.59], p < 0.001) and significant reduction in malondialdehyde (MDA) concentrations (−0.77, [−1.06, −0.47], p < 0.001) were shown after CoQ10 supplementation compared to placebo. However, we could not determine that there was a significant increase in circulating superoxide dismutase (SOD) levels yet (0.47, [0.00, 0.94], p = 0.05). Subgroup analyses implied that CoQ10 supplementation was more beneficial to people with coronary artery disease or type 2 diabetes. Additionally, taking 100−150 mg/day CoQ10 supplement had better benefits for the levels of TAC, MDA and SOD (all p < 0.01). These results to a statistically significant extent lent support to the efficacy and optimal dose of CoQ10 supplementation on attenuating oxidative stress status in adults.

The effects of coenzyme Q10 supplementation on biomarkers of inflammation and oxidative stress in among coronary artery disease: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

Systemic inflammation and oxidative stress significantly contribute in developing coronary artery disease (CAD). This systematic review and meta-analysis was aimed to determine the effects of coenzyme Q10 (CoQ10) supplementation on biomarkers of inflammation and oxidative stress among patients with CAD.

METHODS

The electronic databases including MEDLINE, EMBASE, Scopus, Web of Science, and Cochrane Library databases were systematically searched until Oct 2018. The quality assessment and heterogeneity of the selected randomized clinical Trials (RCTs) were examined using the Cochrane Collaboration risk of bias tool, and Q and I² tests, respectively. Given the presence of heterogeneity, random-effects model or fixed-effect model were used to pool standardized mean differences (SMDs) as summary effect sizes.

RESULTS

A total of 13 clinical RCTs of 912 potential citations were found to be eligible for the current meta-analysis. The pooled findings for biomarkers of inflammation and oxidative stress demonstrated that CoQ10 supplementation significantly increased superoxide dismutase (SOD) (SMD 2.63; 95% CI, 1.17, 4.09, P < 0.001; I² = 94.5%) and catalase (CAT) levels (SMD 1.00; 95% CI, 0.57, 1.43, P < 0.001; I² = 24.5%), and significantly reduced malondialdehyde (MDA) (SMD - 4.29; 95% CI - 6.72, - 1.86, P = 0.001; I² = 97.6%) and diene levels (SMD - 2.40; 95% CI - 3.11, - 1.68, P < 0.001; I² = 72.6%). We did not observe any significant effect of CoQ10 supplementation on C-reactive protein (CRP) (SMD - 0.62; 95% CI - 1.31, 0.08, P = 0.08; I² = 87.9%), tumor necrosis factor alpha (TNF-α) (SMD 0.22; 95% CI - 1.07, 1.51, P = 0.73; I² = 89.7%), interleukin-6 (IL-6) (SMD - 1.63; 95% CI - 3.43, 0.17, P = 0.07; I² = 95.2%), and glutathione peroxidase (GPx) levels (SMD 0.14; 95% CI - 0.77, 1.04, P = 0.76; I² = 78.7%).

CONCLUSIONS

Overall, this meta-analysis demonstrated CoQ10 supplementation increased SOD and CAT, and decreased MDA and diene levels, but did not affect CRP, TNF-α, IL-6, and GPx levels among patients with CAD.

The effects of coenzyme Q10 supplementation on lipid profiles among patients with coronary artery disease: a systematic review and meta-analysis of randomized controlled trials

Background

Chronic inflammation and increased oxidative stress significantly contribute in developing coronary artery disease (CAD). Hence, antioxidant supplementation might be an appropriate approach to decrease the incidence of CAD. This systematic review and meta-analysis was aimed to determine the effects of coenzyme Q10 (CoQ10) supplementation on lipid profile, as one of the major triggers for CAD, among patients diagnosed with coronary artery disease.

Methods

EMBASE, Scopus, PubMed, Cochrane Library, and Web of Science were searched for studies prior to May 20th, 2018. Cochrane Collaboration risk of bias tool was applied to assess the methodological quality of included trials. I-square and Q-tests were used to measure the existing heterogeneity across included studies. Considering heterogeneity among studies, fixed- or random-effect models were applied to pool standardized mean differences (SMD) as overall effect size.

Results

A total of eight trials (267 participants in the intervention group and 259 in placebo group) were included in the current meta-analysis. The findings showed that taking CoQ10 by patients with CAD significantly decreased total-cholesterol (SMD -1.07; 95% CI, − 1.94, − 0.21, P = 0.01) and increased HDL-cholesterol levels (SMD 1.30; 95% CI, 0.20, 2.41, P = 0.02). We found no significant effects of CoQ10 supplementation on LDL-cholesterol (SMD -0.37; 95% CI, − 0.87, 0.13, P = 0.14), lipoprotein (a) [Lp(a)] levels (SMD -1.12; 95% CI, − 2.84, 0.61, P = 0.20) and triglycerides levels (SMD 0.01; 95% CI, − 0.22, 0.24, P = 0.94).

Conclusions

This meta-analysis demonstrated the promising effects of CoQ10 supplementation on lowering lipid levels among patients with CAD, though it did not affect triglycerides, LDL-cholesterol and Lp(a) levels.

A meta-analysis of randomized and placebo-controlled clinical trials suggests that coenzyme Q10 at low dose improves glucose and HbA1c levels

The influence of coenzyme Q10 (CoQ10) on blood glucose (BGL) and HbA1c (HL) levels has been previously investigated; however, the results are inconsistent. Therefore, the purpose of this meta-analysis was to determine if CoQ10 could affect BGL and HL levels based on the existing evidence. PubMed, Cochrane Library, Web of Science, Embase, and Scopus databases were searched for randomized clinical trials from September 1, 1956, to March 01, 2016. To calculate pooled overall effects, a random effect model was used. Because of the presence of heterogeneity, the subgroup analysis and the meta-regression were performed. In total, 18 studies (19 study arms) were included in our investigation focusing on the effects of CoQ10 on BGL (17 arms) and HL (12 arms) changes. CoQ10 significantly reduced BGL, whereas it was ineffective in the reduction of the HL. Because of the significant heterogeneity, in the arms involving BGL, we found that lower doses of CoQ10 (<200 mg/d) and a shorter duration of study created a positive effect on BGL. Also, it appeared that CoQ10 could reduce BGL in patients with a glucose level >6 mmol/L as well as in certain ethnic groups. However, because the meta-regression failed to support the subgroup analysis, the result related to the ethnic group should be used only to generate a hypothesis, which is planned in the future. In conclusion, CoQ10 can reduce BGL, particularly when used in lower doses (< 200 mg/d) and when administration was not longer than 12 weeks, in patients both with and without high BGL.

Supplementation with coenzyme Q10 reduces plasma lipoprotein(a) concentrations but not other lipid indices: A systematic review and meta-analysis

Plasma lipoprotein(a) [Lp(a)] elevations are associated with increased cardiovascular risk. Coenzyme Q10 (CoQ10) is a member of the mitochondrial respiratory chain with a prominent role as a potent gene regulator. The Lp(a)-lowering efficacy of CoQ10 has been investigated in different clinical settings with contrasting results. A systematic literature search in Medline, SCOPUS, Web of Science and Google Scholar databases was conducted to identify controlled trials investigating the efficacy of CoQ10 supplementation on plasma Lp(a) levels. Inverse variance-weighted mean differences (WMDs) and 95% confidence intervals (CIs) were calculated for net changes in Lp(a) levels using a random-effects model. Random-effects meta-regression was performed to assess the effect of putative confounders on plasma Lp(a) levels. Seven randomized controlled trials with a total of 409 subjects (206 in the CoQ10 arm and 203 in the control arm) met the eligibility criteria. Overall, CoQ10 supplementation was paralleled by a slight but significant reduction of plasma Lp(a) levels (WMD: -3.54 mg/dL, 95% CI: -5.50, -1.58; p<0.001), this effect being more robust in those trials with higher baseline Lp(a) levels (slope: -0.44; 95% CI: -0.80, -0.08; p=0.018). Reduction of plasma Lp(a) levels was consistent across different CoQ10 doses, with an inverse association between administered CoQ10 dose and Lp(a) lowering (slope: 0.04; 95% CI: 0.01, 0.07; p=0.004). Neither total cholesterol and cholesterol subfractions, nor triglyceride levels were affected by CoQ10 supplementation. In conclusion, CoQ10 supplementation, in the tested range of doses, reduces plasma Lp(a) concentrations, particularly in patients with Lp(a)≥ 30 mg/dL. Other lipid indices were not altered by CoQ10 supplementation.

Current experience in testing mitochondrial nutrients in disorders featuring oxidative stress and mitochondrial dysfunction: rational design of chemoprevention trials

An extensive number of pathologies are associated with mitochondrial dysfunction (MDF) and oxidative stress (OS). Thus, mitochondrial cofactors termed "mitochondrial nutrients" (MN), such as α-lipoic acid (ALA), Coenzyme Q10 (CoQ10), and l-carnitine (CARN) (or its derivatives) have been tested in a number of clinical trials, and this review is focused on the use of MN-based clinical trials. The papers reporting on MN-based clinical trials were retrieved in MedLine up to July 2014, and evaluated for the following endpoints: (a) treated diseases; (b) dosages, number of enrolled patients and duration of treatment; (c) trial success for each MN or MN combinations as reported by authors. The reports satisfying the above endpoints included total numbers of trials and frequencies of randomized, controlled studies, i.e., 81 trials testing ALA, 107 reports testing CoQ10, and 74 reports testing CARN, while only 7 reports were retrieved testing double MN associations, while no report was found testing a triple MN combination. A total of 28 reports tested MN associations with "classical" antioxidants, such as antioxidant nutrients or drugs. Combinations of MN showed better outcomes than individual MN, suggesting forthcoming clinical studies. The criteria in study design and monitoring MN-based clinical trials are discussed.

Effects of coenzyme q10 supplementation on serum lipoproteins, plasma fibrinogen, and blood pressure in patients with hyperlipidemia and myocardial infarction

BACKGROUND

Low plasma concentrations of coenzyme Q10 (CoQ10) have been associated with concentration of lipoproteins and other factors contributing to coronary heart diseases.

OBJECTIVES

The present investigation aimed to improve the blood pressure and serum lipoproteins concentration in patients with myocardial infarction (MI) by CoQ10 supplementation.

PATIENTS AND METHODS

In this randomized double-blinded controlled clinical trial, 52 Iranian patients with hyperlipidemia and MI were recruited to examine the effect of CoQ10 on serum total cholesterol (TC), LDL-C, HDL-C, triglyceride (TG), LDL-C/HDL-C ratio, TC/HDL-C ratio, fibrinogen, systolic blood pressure (SBP) and diastolic blood pressure (DBP). Individuals were randomly allocated to two groups for receiving either 200 mg/d of CoQ10 or placebo for 12 weeks.

RESULTS

There were not significant differences in serum LDL-C (2.70 ± 0.31 vs. 2.70 ± 0.35 mmol/L), TC (4.47 ± 0.33 vs. 4.93 ± 0.57 mmol/L), TG (2.48 ± 0.12 vs. 2.25 ± 0.69 mmol/L), and fibrinogen (2.08 ± 0.99 vs. 38.7 ± 0.64 mg/dL) between CoQ10 and placebo groups. After 12 weeks, a significant enhancement in serum HDL-C (1.44 ± 0.18 vs. 1.14 ± 0.18 mmol/L) level was observed between groups after the supplementation (P < 0.001). A significant reduction of TC, LDL-C, and fibrinogen and a significant increase in HDL-C concentration was observed in CoQ10 group after intervention (P < 0.001). Our assessment demonstrated statistically significant differences between the two groups in SBP and DBP after intervention (P < 0.001). ANCOVA also revealed significant differences in the ratio of LDL-C/HDL-C and TC/HDL-C between the two groups (1.89 ± 0.42 vs. 2.39 ± 0.38, P = 0.002; and 3.2 ± 0.5 vs. 4.24 ± 0.66, P = 0.01, respectively). A significant reduction of LDL-C/HDL-C and TC/HDL-C was observed in CoQ10 group (P < 0.001).

CONCLUSIONS

Twelve-week supplementation with CoQ10 in patients with hyperlipidemia and MI can improve blood pressure, serum HDL-C as well as LDL-C/HDL-C and TC/HDL-C ratios; therefore, it might decrease the risk of frequent MI.

A guide to diagnosis and treatment of Leigh syndrome

Leigh syndrome is a devastating neurodegenerative disease, typically manifesting in infancy or early childhood. However, also late-onset cases have been reported. Since its first description by Denis Archibald Leigh in 1951, it has evolved from a postmortem diagnosis, strictly defined by histopathological observations, to a clinical entity with indicative laboratory and radiological findings. Hallmarks of the disease are symmetrical lesions in the basal ganglia or brain stem on MRI, and a clinical course with rapid deterioration of cognitive and motor functions. Examinations of fresh muscle tissue or cultured fibroblasts are important tools to establish a biochemical and genetic diagnosis. Numerous causative mutations in mitochondrial and nuclear genes, encoding components of the oxidative phosphorylation system have been described in the past years. Moreover, dysfunctions in pyruvate dehydrogenase complex or coenzyme Q10 metabolism may be associated with Leigh syndrome. To date, there is no cure for affected patients, and treatment options are mostly unsatisfactory. Here, we review the most important clinical aspects of Leigh syndrome, and discuss diagnostic steps as well as treatment options.

Diabetic cardiomyopathy: mechanisms and new treatment strategies targeting antioxidant signaling pathways

Cardiovascular disease is the primary cause of morbidity and mortality among the diabetic population. Both experimental and clinical evidence suggest that diabetic subjects are predisposed to a distinct cardiomyopathy, independent of concomitant macro- and microvascular disorders. 'Diabetic cardiomyopathy' is characterized by early impairments in diastolic function, accompanied by the development of cardiomyocyte hypertrophy, myocardial fibrosis and cardiomyocyte apoptosis. The pathophysiology underlying diabetes-induced cardiac damage is complex and multifactorial, with elevated oxidative stress as a key contributor. We now review the current evidence of molecular disturbances present in the diabetic heart, and their role in the development of diabetes-induced impairments in myocardial function and structure. Our focus incorporates both the contribution of increased reactive oxygen species production and reduced antioxidant defenses to diabetic cardiomyopathy, together with modulation of protein signaling pathways and the emerging role of protein O-GlcNAcylation and miRNA dysregulation in the progression of diabetic heart disease. Lastly, we discuss both conventional and novel therapeutic approaches for the treatment of left ventricular dysfunction in diabetic patients, from inhibition of the renin-angiotensin-aldosterone-system, through recent evidence favoring supplementation of endogenous antioxidants for the treatment of diabetic cardiomyopathy. Novel therapeutic strategies, such as gene therapy targeting the phosphoinositide 3-kinase PI3K(p110α) signaling pathway, and miRNA dysregulation, are also reviewed. Targeting redox stress and protective protein signaling pathways may represent a future strategy for combating the ever-increasing incidence of heart failure in the diabetic population.

Effects of coenzyme Q10 and α-lipoic acid supplementation in fructose fed rats

This study was conducted to investigate the effects of α-lipoic acid and coenzyme Q10 on plasma levels of lipids, asymmetric dimethylarginine, oxidative stress in fructose fed rats which provide a model of dietary-induced insulin resistance and to evaluate vascular changes developing in these rats by histologically. Male Sprague Dawley rats were used in this study. The animals were divided into 4 groups. Group 1 did not receive any medication and served as a control. Group 2 received a regular diet and water ad libitum and fructose was administered as % 10 solution in drinking water. Group 3 received α-lipoic acid (100 mg/kg/day) i.p. for 5 weeks and Group 4 received coenzyme Q10 (10 mg/kg/day) i.p. for 5 weeks. For determination of plasma asymmetric dimethylarginine, glutathione and malondialdehyde levels, high-performance liquid chromatography system was used. Homeostatic model assessment as a measure of insulin resistance was calculated. Lipid profile measurements were determined using enzymatic assay on an Auto analyzer. The high fructose diet was significantly associated with an increase in levels of plasma LDL, VLDL and total cholesterol and decrease in level of HDL cholesterol. Plasma asymmetric dimethylarginine, malondialdehyde and glutathione levels were also increase in these rats. α-lipoic acid or coenzyme Q10 supplementation was found to have some positive effect on these parameters. These findings were also demonstrated by morphological observation of the aorta. We demonstrated that administration of α-lipoic acid and coenzyme Q10 notably suppresses oxidative and nitrative stress, hyperinsulinemia, insulin resistance developing in fructose fed rats, a model of metabolic syndrome (MS). These positive effects of α-lipoic acid or coenzyme Q10 can be attributed to its antioxidant activity.

Influence of gel and powdered formulations of coenzyme Q10 on metabolic parameters in rats

The healthful benefits of two commercially available formulations of coenzyme Q10 (Co Q10), one in gel and the other in a powdered form, on a variety of metabolic parameters in Sprague-Dawley rats (SD) were compared to control. The principal metabolic parameters examined were systolic blood pressure (SBP), DNA fragmentation, and free radical formation in hepatic and renal tissues. Compared to control, the powdered formulation significantly decreased SBP in the normotensive SD, whereas both commercial formulations lowered hepatic and renal DNA fragmentation and free radical formation. The gel-formulation lowered hepatic DNA fragmentation more than the powdered-formulation. In conclusion, both gel- and powdered-formulations of Co Q10 significantly influenced the metabolic parameters assessed in a favorable fashion, with the powdered-formulation more effective on SBP and the gel-formulation more effective on overcoming hepatic DNA fragmentation. From the data, we conclude that the choice of the formulation containing Co Q10 to be used should be based on the desired healthful benefits.

Ubiquinol-10/lipids ratios in consecutive patients with different angiographic findings

OBJECTIVE

Information concerning un-supplemented plasma concentrations of ubiquinol-10 in coronary artery disease patients is still controversial. The aim of this study is to determine the levels of plasma ubiquinol-10 and ratios of ubiquinol-10 to plasma lipids in consecutive patients with different angiographic findings.

SUBJECTS AND METHODS

Thirty-six consecutive patients who underwent coronary angiography were split in two groups with different atherosclerotic changes. These patients were un-supplemented with antioxidants and were not treated by lipid-lowering medication. We have measured a plasma level of ubiquinol-10 using high-performance liquid chromatography with coulometric detection. Conventional plasma lipids, markers of oxidative stress and other widely accepted risk factors of atherosclerosis have been determined too.

RESULTS

Plasma ubiquinol-10 to low-density lipoprotein cholesterol (LDL-C) ratios in patients with different angiographic findings have been found as 180+/-69 and 132+/-43, respectively (p=0.020). The ubiquinol-10/LDL-C ratio was significantly lower in angiographically positive patients. There were also significant differences in ubiquinol-10 per total cholesterol (109+/-47 and 80+/-26, respectively; p=0.031), per triglycerides (426+/-191 and 237+/-86, respectively; p=0.002) and per the sum of triglycerides and total cholesterol (86+/-35 and 61+/-20, respectively; p=0.013).

CONCLUSIONS

There have not been found any significant differences between levels of widely accepted risk factors for genesis and progress of atherosclerotic changes in these two groups of patients. Only the level of triglycerides and the total cholesterol minus high-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratio were significantly higher in patients with stenosis. This ratio correlated with the ubiquinol-10/LDL-C ratio, which was significantly lower in patients with stenosis. Our results indicate that the ratio of ubiquinol-10/LDL-C is likely to be a risk factor for atherogenesis.

Supplemental Conditionally Essential Nutrients in Cardiovascular Disease Therapy

Conditionally essential nutrients (CENs) are organic compounds that are ordinarily produced by the body in amounts sufficient to meet its physiological requirements. However, in disorders, such as cardiovascular disease (CVD), and in other physiologically stressful conditions, their biosynthesis may be inadequate. Under these circumstances, CENs become essential nutrients, comparable to vitamins. The CENs of primary importance in CVD, based on the quantity and quality of human clinical studies, are l-arginine, l-carnitine, propionyl-l-carnitine, and coenzyme Q10. Controlled studies of these CENs are reviewed in depth. Taurine is a CEN of secondary importance caused by a limited human database. Other putative CENs include alpha-lipoic acid, betaine, chondroitin sulfate, glutamine, and d-ribose, each of which is mentioned in passing. Collectively, CENs have demonstrated favorable clinical effects in CVDs, including chronic heart failure, myocardial infarction, angina pectoris, and in CVD risk factors, such as hypertension, hyperlipidemia, and lipoprotein(a). Limited research has pointed to possible benefits in CVD therapy accruing from supplementation with several CENs in combination. Additional controlled clinical studies of CENs in CVD are urgently needed. In view of the efficacy and safety of appropriate supplementation with CENs, it is strongly suggested that healthcare professionals become knowledgeable of these potentially important additions to the CVD therapeutic armamentarium.

Possible role of ubiquinone in the treatment of massive hypertriglyceridemia resistant to PUFA and fibrates

OBJECTIVE

To describe the effect of Coenzyme Q10 (CoQ10) (added to either a fibrate, or polyunsaturated fatty acids (PUFA) or association of both) in patients affected by massive hypertriglyceridemia (MHTG) resistant to fibrates and PUFA.

DESIGN

Open, sequential, comparative intervention study.

SETTING

Specialised centres for dyslipidemia management.

SUBJECTS

Fifteen subjects (mean age: 45.1+/-12.5 years) affected by MHTG and hyporesponsive to either fibrates, or PUFA, or fibrates-PUFA association, and 15 age-matched subjects regularly responders to PUFA and fenofibrate treatment.

INTERVENTIONS

Treatment for periods of 6 weeks each with the following consecutive treatments: CoQ10 150 mg/day, PUFA 3000 mg/day, fenofibrate 200 mg/day, PUFA 3000 mg/day+fenofibrate 200 mg/day, PUFA 3000 mg/day+CoQ10 150 mg/day, fenofibrate 200 mg/day+CoQ10 150 mg/day, and finally, fenofibrate 200 mg/day+PUFA 3000 mg/day + CoQ10 150 mg/day.

RESULTS

CoQ10 supplementation did not improve any monitored parameter in the control group except for systolic and diastolic blood pressure, creatinine and Lp(a) plasma levels, both during fenofibrate and/or PUFA treatment. In MHTG group, CoQ10 supplementation significantly improved TG, TC, Lp(a), uric acid and blood pressure during fenofibrate treatment, but only Lp(a) and blood pressure during PUFA treatment. Fenofibrate appeared to have better effect on hsCRP and gamma-GT plasma levels than PUFA. No significant change was observed in any group and under any treatment in regards to homocysteinemia, PAI-1, or t-PA.

CONCLUSION

Even though the mechanism of action through which the effects were obtained is yet to be elucidated, adding CoQ10 to fenofibrate could improve the drug's efficacy in MHTG patients not responding to fenofibrate alone.

Treatment of massive hypertriglyceridemia resistant to PUFA and fibrates: a possible role for the coenzyme Q10?

OBJECTIVE

To describe the effect of CoQ10 (added to either a fibrate, or PUFA or association of both) in patients affected by massive hypertriglyceridemia (MHTG) resistant to fibrates and PUFA.

DESIGN

Open, sequential, comparative intervention study.

SETTING

Specialised centres for dyslipidemia management.

SUBJECTS

15 subjects (mean age: 45.1 +/- 12.5 years) affected by MHTG and hyporesponsive to either fibrates, or PUFA, or fibrates-PUFA association, and 15 age-matched subjects regularly responders to PUFA and fenofibrate treatment.

INTERVENTIONS

Treatment for periods of 6 weeks each with the following consecutive treatments: CoQ10 150 mg/day, PUFA 3000 mg/day, fenofibrate 200 mg/day, PUFA 3000 mg/day + fenofibrate 200 mg/day, PUFA 3000 mg/day + CoQ10 150 mg/day, fenofibrate 200 mg/day + CoQ10 150 mg/day, and finally, fenofibrate 200 mg/day + PUFA 3000 mg/day + CoQ10 150 mg/day.

RESULTS

CoQ10 supplementation improved, in the control group, systolic and diastolic blood pressure, creatinine and Lp(a) plasma levels, both during fenofibrate and/or PUFA treatment. In MHTG group, CoQ10 supplementation significantly improved TG, TC, Lp(a), uric acid and blood pressure during fenofibrate treatment, but only Lp(a) and blood pressure during PUFA treatment. Fenofibrate appeared to have better effect on hsCRP and gamma-GT plasma levels than PUFA. No significant change was observed in any group and under any treatment in regards to homocysteinemia, PAI-1, or t-PA.

CONCLUSION

Even though the mechanism of action through which the effects were obtained is yet to be elucidated, adding CoQ10 to fenofibrate could improve the drug's efficacy in MHTG patients not responding to fenofibrate alone.

Increased concentrations of lipoprotein(a), circadian rhythms and metabolic reactions evoked by acute myocardial infarction, associated with acute reactions in relation to large breakfasts

Of 54 patients with acute coronary artery disease (CAD) that were included in this study, 41 patients had acute myocardial infarction (AMI), five patients possible MI, four patients unstable angina and the remaining four angina pectoris. The control subjects (n = 85) were randomly selected from the general population of the city of Moradabad of similar age range after exclusion for CAD (n = 9), diabetes (n = 6) and excess intake of trans fatty acids (n = 20). The incidence of lipoprotein(a) excess (> 30 mg/dl; 42.6 vs 24.7%; P < 0.05) and mean concentration of lipoprotein(a) (Lp[a], 6.4 mg/dl, 95% confidence interval: 2.8-10.5; P < 0.05) was significantly greater in the acute CAD group compared with control subjects. Mean total cholesterol and triglycerides were significantly higher and mean nitrite level lower in the study group as compared with the control group.There was a significant greater incidence of cardiac events in the second quarter of the day compared with the fourth quarter. Lp(a), triglycerides, blood glucose, plasma insulin, malondialdehyde, diene conjugates, TBARS and TNF-alpha and IL-6 levels, which were significantly greater during the acute phase, showed a significant decline and serum nitrite and coenzyme Q demonstrated an increase at 4 weeks of follow-up when the acute reactions evoked by MI had been controlled. Large breakfasts were a predisposing factor for cardiac events in the second quarter of the day and it was significantly associated with metabolic reactions. The findings indicate that acute reactions as a result or as circadian rhythms appear to be important in the pathogenesis of AMI-associated complications and that a large breakfast in association with nitrite deficiency may further trigger the circadian rhythms. However, more studies in a larger number of subjects would be necessary in order to confirm our findings.

Amelioration of ethanol-induced growth retardation by all-trans-retinoic acid and α-tocopherol in shell-less culture of the chick embryo

The mechanisms of teratogenic action of ethanol (EtOH) were investigated by testing the hypothesis that all-trans-retinoic acid and/or alpha-tocopherol ameliorates ethanol-induced embryonic growth retardation. Chicken embryos were explanted in shell-less cultures and a single dose of EtOH (15, 30, or 50%) or 50% EtOH with either all-trans-retinoic acid (10(-8)M) or alpha-tocopherol (0.05 M) or a mix of all-trans-retinoic acid (10(-8)M) and alpha-tocopherol (0.05 M) was applied to the center of the blastodisc. EtOH significantly increased the mortality rate and induced growth retardation in a dose-dependent manner. In addition, EtOH increased malondialdehyde (MDA) levels, an indicator of oxidative stress and cell damage, in a dose dependent manner. All-trans-retinoic acid, the active form of Vitamin A, and/or alpha-tocopherol, an antioxidant, co-treatment with EtOH significantly diminished both the EtOH-induced mortality and growth retardation. However, only alpha-tocopherol co-treatment reduced the MDA levels. Thus, the mechanisms of teratogenic action of EtOH appear to involve initiation of oxidative stress as well as perturbation of retinoic acid (RA) signaling. It also appears likely that these mechanisms work independently of each other.

The placebo effect and randomized trials: analysis of alternative medicine

Randomized controlled trials are generally regarded as the gold standard of study designs to determine causality. The inclusion of a placebo group in these trials, when appropriate, is critical to access the efficacy of a drug or supplement. The placebo response itself has received some attention in the medical literature over the past fifty years. The recent increasing utilization of dietary supplements and herbal medications by patients makes it imperative to reevaluate the placebo response in conventional and alternative medicine. This article will review some of the negative and positive results from randomized trials utilizing dietary supplements (androstenedione, beta-carotene, CoQ10, garlic, soy, vitamin C and E...) for a number of non-urologic and urologic conditions, including cancer.