Cardiovascular mortality and N-terminal-proBNP reduced after combined selenium and coenzyme Q10 supplementation: A 5-year prospective randomized double-blind placebo-controlled trial among elderly Swedish citizens

Comprehensive Insights into the Health Effects of Selenium Exposure and Supplementation Among the Chinese Community Middle-Aged and Elderly: a Combined Retrospective Cohort Study and Intervention Study

Selenium (Se) is an essential trace element for maintaining human health, for example, plays a crucial role in preventing aging-related diseases. However, most studies on the health effects of Se among the community middle-aged and elderly have been observational or the health indices were single, and the related study among the Chinese population is limited. Additionally, China is recognized as among the countries facing a significant deficiency in Se, and Se contents in the human body may decrease with age. Therefore, a two-step study was conducted to explore the health effects of Se exposure and supplementation among such populations in China. Firstly, a retrospective cohort study was conducted to compare the health outcomes between such populations residing in Se-rich regions and non-Se-rich regions, involving a total of 102 subjects, with 51 residing in Se-rich regions and 51 in non-Se-rich regions. The hair-Se (H-Se) contents, serum-Se (S-Se) contents, and total cholesterol of subjects from Se-rich regions were significantly higher than their counterparts. Notably, significant positive associations were observed between S-Se and lipids. Secondly, a before-after self-control Se supplementation study among subjects residing in non-Se-rich regions was conducted. A total of 40 subjects administered Se tablets orally for 30 days, with Se of 120 μg/day. The results showed significant increases in H-Se and S-Se. Se supplementation also exhibited positive effects on alanine aminotransferase, homocysteine, and fasting glucose; however, high-density lipoprotein cholesterol significantly decreased. Overall, the community middle-aged and elderly residing in Se-rich regions or receiving quantitative Se supplementation could effectively improve Se contents in bodies and certain health indices, excluding lipids. These improvements encompass liver function, cardiovascular health, and glucose metabolism. These findings enhance our understanding of how Se impacts the health of the middle-aged and elderly, emphasizing the significance of targeted interventions for such populations in non-Se-rich regions. Trial registration: ChiCTR2000040987 ( https://www.chictr.org.cn ).

Supplementation with selenium and coenzyme Q10 in an elderly Swedish population low in selenium - positive effects on thyroid hormones, cardiovascular mortality, and quality of life

BACKGROUND

Selenium-dependent deiodinases play a central role in thyroid hormone regulation and metabolism. In many European countries, insufficient selenium intake may consequently lead to adverse effects on thyroid function. In this randomised placebo-controlled double-blind study, we examined the effect of supplementation with selenium and coenzyme Q10 on thyroid hormonal status, cardiovascular (CV) mortality and health-related quality of life (Hr-QoL).

METHODS

Free T3, free T4, reverse T3, and TSH were determined in 414 individuals at baseline, and the effect of selenium yeast (200 µg/day) and coenzyme Q10 (200 mg/day) supplementation on hormone concentrations, CV mortality and Hr-QoL was evaluated after 48 months using Short Form 36 (SF-36). Pre-intervention plasma selenium was low, mean 67 µg/L, corresponding to an estimated intake of 35 µg/day. Changes in concentrations of thyroid hormones following the intervention were assessed using T-tests, repeated measures of variance, and ANCOVA analyses.

RESULTS

In the total population, the group with the lowest selenium concentration at baseline presented with significantly higher levels of TSH and lower levels of fT3 as compared to subjects with the highest selenium concentration. Supplementation with selenium and coenzyme Q10 for 4 years significantly increased fT3 and rT3, decreased fT4, and diminished the increase in TSH levels compared with placebo treatment (p = 0.03, all). In the placebo group, TSH and fT4 values above the median were associated with an increase in 10-year CV mortality, as compared with the mortality rate among those with TSH and fT4 below the median (p < 0.04, both), with no difference in mortality rate according to TSH and fT4 levels in the active intervention group. Similarly, TSH > median and fT3 < median were associated with a decline in mental Hr-QoL measures vs. TSH < and fT3 > median in the placebo group during 4 years of follow-up, but this was wiped out in the active group.

CONCLUSIONS

Supplementation with selenium and coenzyme Q10 had a beneficial effect on thyroid hormones with respect to CV mortality and Hr-QoL outcomes. The initial deficient selenium status was associated with an impaired thyroid function and the changes in thyroid hormone levels can be explained by increased activity of deiodinases. We conclude that a substantial part of the elderly study population might suffer from suboptimal thyroidal function with adverse clinical implications due to selenium deficiency.

TRIAL REGISTRATION

This study was registered at ClinicalTrials.gov and has the identifier NCT01443780. Since it was not mandatory to register at the time the study began, the study has been registered retrospectively.

Mitochondrial Dysfunction and Coenzyme Q10 Supplementation in Post-Viral Fatigue Syndrome: An Overview

Post-viral fatigue syndrome (PVFS) encompasses a wide range of complex neuroimmune disorders of unknown causes characterised by disabling post-exertional fatigue, myalgia and joint pain, cognitive impairments, unrefreshing sleep, autonomic dysfunction, and neuropsychiatric symptoms. It includes myalgic encephalomyelitis, also known as chronic fatigue syndrome (ME/CFS); fibromyalgia (FM); and more recently post-COVID-19 condition (long COVID). To date, there are no definitive clinical case criteria and no FDA-approved pharmacological therapies for PVFS. Given the current lack of effective treatments, there is a need to develop novel therapeutic strategies for these disorders. Mitochondria, the cellular organelles responsible for tissue energy production, have recently garnered attention in research into PVFS due to their crucial role in cellular bioenergetic metabolism in these conditions. The accumulating literature has identified a link between mitochondrial dysfunction and low-grade systemic inflammation in ME/CFS, FM, and long COVID. To address this issue, this article aims to critically review the evidence relating to mitochondrial dysfunction in the pathogenesis of these disorders; in particular, it aims to evaluate the effectiveness of coenzyme Q10 supplementation on chronic fatigue and pain symptoms as a novel therapeutic strategy for the treatment of PVFS.

Coenzyme Q10 for Enhancing Physical Activity and Extending the Human Life Cycle

BACKGROUND

Coenzyme Q (CoQ) is an enzyme family that plays a crucial role in maintaining the electron transport chain and antioxidant defense. CoQ10 is the most common form of CoQ in humans. A deficiency of CoQ10 occurs naturally with aging and may contribute to the development or progression of many diseases. Besides, certain drugs, in particular, statins and bisphosphonates, interfere with the enzymes responsible for CoQ10 biosynthesis and, thus, lead to CoQ10 deficiency.

OBJECTIVES

This article aims to evaluate the cumulative studies and insights on the topic of CoQ10 functions in human health, focusing on a potential role in maintaining physical activity and extending the life cycle.

RESULTS

Although supplementation with CoQ10 offers many benefits to patients with cardiovascular disease, it appears to add little value to patients suffering from statin-associated muscular symptoms. This may be attributed to substantial heterogeneity in doses and treatment regimens used.

CONCLUSION

Therefore, there is a need for further studies involving a greater number of patients to clarify the benefits of adjuvant therapy with CoQ10 in a range of health conditions and diseases.

Comparison of Coenzyme Q10 (Ubiquinone) and Reduced Coenzyme Q10 (Ubiquinol) as Supplement to Prevent Cardiovascular Disease and Reduce Cardiovascular Mortality

PURPOSE OF REVIEW

According to the World Health Organization (WHO), cardiovascular disease is the leading cause of death worldwide. Heart failure has been defined as a global pandemic leading to millions of deaths. Recent research clearly approved the beneficial effect of Coenzyme Q10 supplementation in treatment and prevention of cardiovascular disease in patients with heart failure in clinical trials but did not distinguish between the oxidised form CoQ10 and reduced form CoQH2 of Coenzyme Q10. The aim of this study is to determine differences in medical application of CoQ10 and CoQH2 supplementation and evaluate the efficacy of CoQ10 and CoQH2 supplementation to prevent cardiovascular disease in patients with heart failure.

RECENT FINDINGS

A PubMed search for the terms "ubiquinone" and "ubiquinol" was conducted, and 28 clinical trials were included. Our findings go along with the biochemical description of CoQ10 and CoQH2, recording cardiovascular benefits for CoQ10 and antioxidative and anti-inflammatory properties for CoQH2. Our main outcomes are the following: (I) CoQ10 supplementation reduced cardiovascular death in patients with heart failure. This is not reported for CoQH2. (II) Test concentrations leading to cardiovascular benefits are much lower in CoQ10 studies than in CoQH2 studies. (III) Positive long-term effects reducing cardiovascular mortality are only observed in CoQ10 studies. Based on the existing literature, the authors recommend CoQ10 instead of CoQH2 to treat and prevent cardiovascular disease in patients with heart failure.

Status of Mitochondrial Oxidative Phosphorylation during the Development of Heart Failure

Mitochondria are specialized organelles, which serve as the "Power House" to generate energy for maintaining heart function. These organelles contain various enzymes for the oxidation of different substrates as well as the electron transport chain in the form of Complexes I to V for producing ATP through the process of oxidative phosphorylation (OXPHOS). Several studies have shown depressed OXPHOS activity due to defects in one or more components of the substrate oxidation and electron transport systems which leads to the depletion of myocardial high-energy phosphates (both creatine phosphate and ATP). Such changes in the mitochondria appear to be due to the development of oxidative stress, inflammation, and Ca2+-handling abnormalities in the failing heart. Although some investigations have failed to detect any changes in the OXPHOS activity in the failing heart, such results appear to be due to a loss of Ca2+ during the mitochondrial isolation procedure. There is ample evidence to suggest that mitochondrial Ca2+-overload occurs, which is associated with impaired mitochondrial OXPHOS activity in the failing heart. The depression in mitochondrial OXPHOS activity may also be due to the increased level of reactive oxygen species, which are formed as a consequence of defects in the electron transport complexes in the failing heart. Various metabolic interventions which promote the generation of ATP have been reported to be beneficial for the therapy of heart failure. Accordingly, it is suggested that depression in mitochondrial OXPHOS activity plays an important role in the development of heart failure.

Can We Slow Down Biological Age Progression? Study Protocol for the proBNPage Reduction (PBAR) Randomized, Double-Blind, Placebo-Controlled Trial (Effects of 4 "Anti-Aging" Food Supplements in Healthy Older Adults)

Purpose

The availability of a simple and reliable marker of biological age might allow an acceleration of the research in the field of longevity extension. Previous studies suggest that this marker might be the N-terminal of B-type natriuretic peptide precursor (NT-proBNP), from which proBNPage, a biological age surrogate, can be calculated. Objectives of the study: 1) To fine-tune the method of proBNPage progression assessment and 2) To establish whether 4 "anti-aging" treatments, which provided promising results in previous studies, can modify proBNPage progression.

Patients and Methods

This is a double-blind randomized placebo-controlled clinical trial on 120 adults aged 65-80 years, free of cardiovascular diseases. Participants will be randomized into 3 groups: A) Coenzyme Q10 100 mg bid + Selenium 100 mcg; B) Resveratrol 350 mg bid + TA-65 (Astragalus Membranaceus extract) 100U; C) Placebo-1 bid + Placebo-2. They will be followed for 2 years and checked 8 times, to assess both proBNPage progression and treatment safety. Secondary variables (handgrip strength, aerobic capacity at the step test and quality of life) will also be assessed. Primary outcome will be the demonstration of significant changes of proBNPage, compared to baseline, in the 3 groups at 6, 12, 18 and 24 months. Secondary outcome will be the demonstration of similar changes of secondary variables. Statistical analyses will be mainly performed by repeated measures ANOVA (both according to intention to treat and per protocol) and paired t tests. The study was approved by the Ethics Committee Area Vasta Emilia Centro, Emilia-Romagna Region, ID: 64/2022/Sper/AOUBo. Trial registration: ClinicalTrials.gov, NCT05500742.

Conclusion

The use of proBNPage as a surrogate of biological age may prove an easy method to select anti-aging treatments worthy of further, more complex assessments.

The Role of Selenium in Atherosclerosis Development, Progression, Prevention and Treatment

Selenium is an essential trace element that is essential for various metabolic processes, protection from oxidative stress and proper functioning of the cardiovascular system. Se deficiency has long been associated with multiple cardiovascular diseases, including endemic Keshan's disease, common heart failure, coronary heart disease, myocardial infarction and atherosclerosis. Through selenoenzymes and selenoproteins, Se is involved in numerous crucial processes, such as redox homeostasis regulation, oxidative stress, calcium flux and thyroid hormone metabolism; an unbalanced Se supply may disrupt these processes. In this review, we focus on the importance of Se in cardiovascular health and provide updated information on the role of Se in specific processes involved in the development and pathogenesis of atherosclerosis (oxidative stress, inflammation, endothelial dysfunction, vascular calcification and vascular cell apoptosis). We also discuss recent randomised trials investigating Se supplementation as a potential therapeutic and preventive agent for atherosclerosis treatment.

Mitochondrial impairment but not peripheral inflammation predicts greater Gulf War illness severity

Gulf War illness (GWI) is an important exemplar of environmentally-triggered chronic multisymptom illness, and a potential model for accelerated aging. Inflammation is the main hypothesized mechanism for GWI, with mitochondrial impairment also proposed. No study has directly assessed mitochondrial respiratory chain function (MRCF) on muscle biopsy in veterans with GWI (VGWI). We recruited 42 participants, half VGWI, with biopsy material successfully secured in 36. Impaired MRCF indexed by complex I and II oxidative phosphorylation with glucose as a fuel source (CI&CIIOXPHOS) related significantly or borderline significantly in the predicted direction to 17 of 20 symptoms in the combined sample. Lower CI&CIIOXPHOS significantly predicted GWI severity in the combined sample and in VGWI separately, with or without adjustment for hsCRP. Higher-hsCRP (peripheral inflammation) related strongly to lower-MRCF (particularly fatty acid oxidation (FAO) indices) in VGWI, but not in controls. Despite this, whereas greater MRCF-impairment predicted greater GWI symptoms and severity, greater inflammation did not. Surprisingly, adjusted for MRCF, higher hsCRP significantly predicted lesser symptom severity in VGWI selectively. Findings comport with a hypothesis in which the increased inflammation observed in GWI is driven by FAO-defect-induced mitochondrial apoptosis. In conclusion, impaired mitochondrial function-but not peripheral inflammation-predicts greater GWI symptoms and severity.

Effects of an Intervention with Selenium and Coenzyme Q10 on Five Selected Age-Related Biomarkers in Elderly Swedes Low in Selenium: Results That Point to an Anti-Ageing Effect-A Sub-Analysis of a Previous Prospective Double-Blind Placebo-Controlled Randomised Clinical Trial

Background: Ageing is associated with cardiovascular disease (CVD). As no single biomarker reflects the full ageing process, we aimed to investigate five CVD- and age-related markers and the effects of selenium and coenzyme Q10 intervention to elucidate the mechanisms that may influence the course of ageing. Methods: This is a sub-study of a previous prospective double-blind placebo-controlled randomized clinical trial that included 441 subjects low in selenium (mean age 77, 49% women). The active treatment group (n = 220) received 200 µg/day of selenium and 200 mg/day of coenzyme Q10, combined. Blood samples were collected at inclusion and after 48 months for measurements of the intercellular adhesion molecule (ICAM-1), adiponectin, leptin, stem cell factor (SCF) and osteoprotegerin (OPG), using ELISAs. Repeated measures of variance and ANCOVA evaluations were used to compare the two groups. In order to better understand and reduce the complexity of the relationship between the biomarkers and age, factor analyses and structural equation modelling (SEM) were performed, and a structural model is presented. Results: Correlation analyses of biomarker values at inclusion in relation to age, and relevant markers related to inflammation, endothelial dysfunction and fibrosis, demonstrated the biomarkers' association with these pathological processes; however, only ICAM1 and adiponectin were directly correlated with age. SEM analyses showed, however, that the biomarkers ICAM-1, adiponectin, SCF and OPG, but not leptin, all had significant associations with age and formed two independent structural factors, both significantly related to age. While no difference was observed at inclusion, the biomarkers were differently changed in the active treatment and placebo groups (decreasing and increasing levels, respectively) at 48 months (p ≤ 0.02 in all, adjusted), and in the SEM model, they showed an anti-ageing impact. Conclusions: Supplementation with selenium/Q10 influenced the analysed biomarkers in ways indicating an anti-ageing effect, and by applying SEM methodology, the interrelationships between two independent structural factors and age were validated.

Lipid-Lowering Nutraceuticals for an Integrative Approach to Dyslipidemia

Dyslipidemia is a treatable risk factor for atherosclerotic cardiovascular disease that can be addressed through lifestyle changes and/or lipid-lowering therapies. Adherence to statins can be a clinical challenge in some patients due to statin-associated muscle symptoms and other side effects. There is a growing interest in integrative cardiology and nutraceuticals in the management of dyslipidemia, as some patients desire or are actively seeking a more natural approach. These agents have been used in patients with and without established atherosclerotic cardiovascular disease. We provide an updated review of the evidence on many new and emerging nutraceuticals. We describe the mechanism of action, lipid-lowering effects, and side effects of many nutraceuticals, including red yeast rice, bergamot and others.

Selenium and coenzyme Q10 improve the systemic redox status while reducing cardiovascular mortality in elderly population-based individuals

BACKGROUND

Serum sulfhydryl groups (R-SH, free thiols) reflect the systemic redox status in health and disease, and may be amenable to therapeutic modulation. Since R-SH are readily oxidized by reactive species, oxidative stress is characterized by reduced serum R-SH levels. Selenium and coenzyme Q₁₀ supplementation may improve the systemic redox status. This study aimed to evaluate the effect of supplementation with selenium and coenzyme Q₁₀ on serum free thiols and to study associations with the risk of cardiovascular mortality in elderly community-dwelling individuals.

METHODS

In this randomized, double-blind, placebo-controlled trial, serum R-SH were measured colorimetrically and adjusted for albumin in 434 individuals at baseline and after 48 months of intervention. Selenium yeast (200 μg/day) and coenzyme Q₁₀ (200 mg/day) or placebo were provided as dietary supplements.

RESULTS

After 48 months of intervention, participants receiving combined selenium and coenzyme Q₁₀ supplementation demonstrated increased levels of serum R-SH compared to placebo (P = 0.002). In prospective association analysis, the highest rate of cardiovascular mortality after a median follow-up of 10 years (IQR: 6.8-10.5) was observed in the lowest quartile (Q1) of R-SH levels. Baseline albumin-adjusted serum R-SH were significantly associated with the risk of cardiovascular mortality, even after adjustment for potential confounding factors (hazard ratio [HR] 1.98 per SD, 95% CI: 1.34-2.91, P < 0.001).

CONCLUSION

Supplementation with selenium and coenzyme Q₁₀ to an elderly community-dwelling population low on the two substances, significantly improved serum R-SH levels, supporting a reduction in systemic oxidative stress. Low serum R-SH levels were significantly associated with an increased risk of cardiovascular mortality in elderly individuals.

Increased SIRT1 Concentration Following Four Years of Selenium and Q10 Intervention Associated with Reduced Cardiovascular Mortality at 10-Year Follow-Up-Sub-Study of a Previous Prospective Double-Blind Placebo-Controlled Randomized Clinical Trial

Background: Selenium and coenzyme Q₁₀ (SeQ₁₀) possess antioxidant and anti-inflammatory properties, potentially mediated via Sirtuin1 (SIRT1). We aimed to investigate the influence of a SeQ₁₀ intervention on SIRT1 concentration, with potential interactions with microRNAs. Methods: In this sub-study of a prospective double-blind placebo-controlled clinical trial, healthy subjects (mean age 76 years) were randomized to receive an active treatment (n = 165, combined 200 µg/day of Se and 200 mg/day of Q₁₀) or a placebo (n = 161). SIRT1 concentration and microRNAs were measured with ELISA and PCR, respectively. Results: After four years, SIRT1 concentration was increased in the active treatment group, with mean (SD) ng/mL of 469 (436) vs. 252 (162), p < 0.001, and decreased in the placebo group, 190 (186) vs. 269 (172), p = 0.002, and the differences between the groups were significant (p = 0.006, adjusted). Those who suffered CV death during a 10-year follow-up (n = 25 and n = 52 in the active treatment and placebo groups, respectively) had significantly lower baseline SIRT1 concentrations compared to the survivors (p < 0.001). MiR-130a-3p was significantly downregulated during the intervention and correlated inversely with SIRT1 at baseline (r = -0.466, p = 0.007). Conclusion: The increased SIRT1 concentration after the SeQ₁₀ intervention associated with reduced CV mortality, partly mediated via miR-1303a-3p, suggests that SIRT1 is an additional mediator of the intervention, preventing vascular ageing.

Selenium, Selenoproteins and 10-year Cardiovascular Risk: Results from the ATTICA Study

BACKGROUND

Selenium (Se) is an essential trace element that is involved in several pathophysiological functions. The relationship of Se with cardiovascular disease remains inconclusive, especially regarding the role of different selenospecies.

OBJECTIVE

The present study assessed the levels of Se distribution in plasma selenoproteins, namely glutathione peroxidase 3 (GPx3), selenoprotein P (SelP) and selenoalbumin (SeAlb) and total Se in selenoproteins in relation to 10-year cardiovascular risk in the ATTICA prospective study.

METHODS

A sub-sample from the ATTICA Study's database, consisting of 278 subjects (114 women and 164 men) with data on Se and selenoproteins levels, was considered. SeGPx3, SelP, and SeAlb in human plasma were simultaneously determined by high-performance liquid chromatography (HPLC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) at baseline. The duration of the follow-up was 8.74 ±2.36 years (mean± standard deviation) and cardiovascular outcomes were recorded. Cox proportional hazards models were applied with total Se or selenoprotein Se as independent variables adjusted for several covariates.

RESULTS

Total Se in selenoproteins was positively related to 10-year relative risk of cardiovascular disease (Hazard Ratios of 3rd vs 2nd tertile 10.02, 95% CI:1.15, 92.34). Subjects with high Se but low SeGPx3, as identified by discordant percentiles in the distribution of SeGPx3 and Se, had a higher cardiovascular risk.

CONCLUSION

The differentiated effects of circulating selenoproteins on cardiovascular disease risk in the present study, suggest the importance of redox regulation by specific selenoproteins.

Coenzyme Q10 in aging and disease

Coenzyme Q10 (CoQ10) is an essential component of the electron transport chain. It also acts as an antioxidant in cellular membranes. It can be endogenously produced in all cells by a specialized mitochondrial pathway. CoQ10 deficiency, which can result from aging or insufficient enzyme function, has been considered to increase oxidative stress. Some drugs, including statins and bisphosphonates, often used by older individuals, can interfere with enzymes responsible for endogenous CoQ10 synthesis. Oral supplementation with high doses of CoQ10 can increase both its circulating and intracellular levels and several clinical trials observed that its administration provided beneficial effects on different disorders such as cardiovascular disease and inflammation which have been associated with low CoQ10 levels and high oxidative stress. Moreover, CoQ10 has been suggested as a promising therapeutic agent to prevent and slow the progression of other diseases including metabolic syndrome and type 2 diabetes, neurodegenerative and male infertility. However, there is still a need for further studies and well-designed clinical trials involving a large number of participants undergoing longer treatments to assess the benefits of CoQ10 for these disorders.

Mitochondrial Dysfunction and Neurodegenerative Disorders: Role of Nutritional Supplementation

Mitochondrial dysfunction has been implicated in the pathogenesis of a number of neurodegenerative disorders, including Parkinson's disease, Alzheimer's disease, amyotrophic lateral sclerosis, multisystem atrophy, and progressive supranuclear palsy. This article is concerned specifically with mitochondrial dysfunction as defined by reduced capacity for ATP production, the role of depleted levels of key nutritionally related metabolites, and the potential benefit of supplementation with specific nutrients of relevance to normal mitochondrial function in the above neurodegenerative disorders. The article provides a rationale for a combination of CoQ10, B-vitamins/NADH, L-carnitine, vitamin D, and alpha-lipoic acid for the treatment of the above neurodegenerative disorders.

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) (-4.77 mmHg, 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 100-200 mg/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.

Novel Targets for a Combination of Mechanical Unloading with Pharmacotherapy in Advanced Heart Failure

LVAD therapy is an effective rescue in acute and especially chronic cardiac failure. In several scenarios, it provides a platform for regeneration and sustained myocardial recovery. While unloading seems to be a key element, pharmacotherapy may provide powerful tools to enhance effective cardiac regeneration. The synergy between LVAD support and medical agents may ensure satisfying outcomes on cardiomyocyte recovery followed by improved quality and quantity of patient life. This review summarizes the previous and contemporary strategies for combining LVAD with pharmacotherapy and proposes new therapeutic targets. Regulation of metabolic pathways, enhancing mitochondrial biogenesis and function, immunomodulating treatment, and stem-cell therapies represent therapeutic areas that require further experimental and clinical studies on their effectiveness in combination with mechanical unloading.

Selenium and Coenzyme Q10 Intervention Prevents Telomere Attrition, with Association to Reduced Cardiovascular Mortality-Sub-Study of a Randomized Clinical Trial

Short telomeres have been associated with ageing and cardiovascular disease. The influence on leukocyte telomere length (LTL) of long-term intervention with combined selenium and coenzyme Q10 is unknown. Our aim was to determine whether 42 months of selenium and coenzyme Q10 supplementation prevented telomere attrition and further cardiovascular mortality. The investigation is an explorative sub-study of a double-blind, placebo-controlled, randomized trial. Swedish citizens low in selenium (n = 118), aged 70−80 years, were included. Intervention time was 4 years, with 10 years’ follow-up time. LTL was relatively quantified with PCR at baseline and after 42 months. At baseline, LTL (SD) was 0.954 (0.260) in the active treatment group and 1.018 (0.317) in the placebo group (p = 0.23). At 42 months, less shortening of LTL was observed after active treatment compared with placebo (+0.019 vs. −0.129, respectively, p = 0.02), with a significant difference in change basing the analysis on individual changes in LTL (p < 0.001). Subjects suffering future death presented with significantly shorter LTL at 42 months than survivors [0.791 (0.190) vs. 0.941 (0.279), p = 0.01], with a significant difference in change of LTL according to cardiovascular mortality and survival (p = 0.03). To conclude, preservation of LTL after selenium and coenzyme Q10 supplementation associated with reduced cardiovascular mortality.

Selenium Status and Its Antioxidant Role in Metabolic Diseases

Selenium (Se), in the form of selenoproteins, is an essential micronutrient that plays an important role in human health and disease. To date, there are at least 25 selenoproteins in humans involved in a wide variety of biological functions, including mammalian development, metabolic progress, inflammation response, chemoprotective properties, and most notably, oxidoreductase functions. In recent years, numerous studies have reported that low Se levels are associated with increased risk, poor outcome, and mortality of metabolic disorders, mainly related to the limited antioxidant defense resulting from Se deficiency. Moreover, the correlation between Se deficiency and Keshan disease has received considerable attention. Therefore, Se supplementation as a therapeutic strategy for preventing the occurrence, delaying the progression, and alleviating the outcomes of some diseases has been widely studied. However, supranutritional levels of serum Se may have adverse effects, including Se poisoning. This review evaluates the correlation between Se status and human health, with particular emphasis on the antioxidant benefits of Se in metabolic disorders, shedding light on clinical treatment.

[Coenzyme Q-10 in the treatment of patients with chronic heart failure and reduced left ventricular ejection fraction: systematic review and meta-analysis]

Aim    The aim of the study was evaluation of the effect of the coenzyme Q10 (Q10) treatment on all-cause and cardiovascular mortality of patients with chronic heart failure (CHF). Q-10 increases the electron transfer in the mitochondrial respiratory chain and exerts anti-inflammatory and antioxidant effects. These effects improve the endothelial function and reduce afterload, which facilitates the heart pumping function. Patients with reduced left ventricular (LV) ejection fraction (EF) (CHFrEF) have low Q10.Material and methods    Criteria of inclusion in the meta-analysis: 1) placebo-controlled studies; 2) enrollment of at least 100 patients; 3) publications after 2010, which implies an optimal basic therapy for CHF; 4) duration of at least 6 months; 5) reported cardiovascular and/or all-cause mortality; 6) using sufficient doses of Q10 (&gt;100 mg/day). The search was performed in CENTRAL, MEDLINE, Embase, Web of Science, E-library, and ClinicalTrials.gov databases. All-cause mortality was the primary efficacy endpoint in this systematic review and the meta-analysis. The secondary endpoint was cardiovascular mortality. Meta-analysis was performed according to the Mantel-Haenszel methods. The Cochrane criterion (I2) was used for evaluation of statistical heterogeneity. The random effects model was used at I2≥50 %, whereas the fixed effects model was used at I2&lt;50.Results    Analysis of studies published from 01.01.2011 to 01.12.2021 identified 357 publications, 23 of which corresponded to the study topic, but only 6 (providing results of four randomized clinical trials, RCT) completely met the predefined criteria. The final analysis included results of managing 1139 patients (586 received Q10 and 553 received placebo). Risk of all-cause death was analyzed by data of four RCTs (1139 patients). The decrease in the risk associated with the Q10 treatment was 36 % (OR=0.64, 95 % CI 0.48-0.87, р=0.004). The heterogeneity of studies was low (Chi2=0.84; p=0.84; I2=0 %). Risk of cardiovascular mortality was analyzed by data of two RCTs (863 patients). The decrease in the risk associated with the Q10 treatment was significant, 55% (OR=0.45, 95 % CI: 0.32-0.64, р=0.00001). In this case, the data heterogeneity was also low (Chi2=0.41; p=0.52; I2=0 %).Conclusion    The meta-analysis confirmed the beneficial effect of coenzyme Q10 on the prognosis of patients with CHFrEF receiving the recommended basic therapy.

Micronutrient deficiencies in heart failure: Mitochondrial dysfunction as a common pathophysiological mechanism?

Heart failure is a devastating clinical syndrome, but current therapies are unable to abolish the disease burden. New strategies to treat or prevent heart failure are urgently needed. Over the past decades, a clear relationship has been established between poor cardiac performance and metabolic perturbations, including deficits in substrate uptake and utilization, reduction in mitochondrial oxidative phosphorylation and excessive reactive oxygen species production. Together, these perturbations result in progressive depletion of cardiac adenosine triphosphate (ATP) and cardiac energy deprivation. Increasing the delivery of energy substrates (e.g., fatty acids, glucose, ketones) to the mitochondria will be worthless if the mitochondria are unable to turn these energy substrates into fuel. Micronutrients (including coenzyme Q10, zinc, copper, selenium and iron) are required to efficiently convert macronutrients to ATP. However, up to 50% of patients with heart failure are deficient in one or more micronutrients in cross-sectional studies. Micronutrient deficiency has a high impact on mitochondrial energy production and should be considered an additional factor in the heart failure equation, moving our view of the failing myocardium away from an "an engine out of fuel" to "a defective engine on a path to self-destruction." This summary of evidence suggests that supplementation with micronutrients-preferably as a package rather than singly-might be a potential therapeutic strategy in the treatment of heart failure patients.

Coenzyme Q10 Reduces Infarct Size in Animal Models of Myocardial Ischemia-Reperfusion Injury: A Meta-Analysis and Summary of Underlying Mechanisms

Objective

Effective interventions that might limit myocardial ischemia-reperfusion (I/R) injury are still lacking. Coenzyme Q₁₀ (CoQ₁₀) may exert cardioprotective actions that reduce myocardial I/R injury. We conducted this meta-analysis to assess the potential cardioprotective effect of CoQ₁₀ in animal models of myocardial I/R injury.

Methods

We searched PubMed and Embase databases from inception to February 2022 to identify animal studies that compared the effect of CoQ₁₀ with vehicle treatment or no treatment on myocardial infarct size in models of myocardial I/R injury. Means and standard deviations of the infarct size measurements were pooled as the weighted mean difference with 95% confidence interval (CI) using the random-effects model. Subgroup analyses were also conducted according to animals' species, models' type, and reperfusion time.

Results

Six animal studies (4 in vivo and 2 ex vivo) with 116 animals were included. Pooled analysis suggested that CoQ₁₀ significantly reduced myocardial infarct size by −11.36% (95% CI: −16.82, −5.90, p < 0.0001, I² = 94%) compared with the control group. The significance of the pooled effect estimate was maintained in rats, Hartley guinea pigs, and Yorkshire pigs. However, it became insignificant in the subgroup of rabbits −5.29% (95% CI: −27.83, 17.26; I² = 87%). Furthermore, CoQ₁₀ significantly reduced the myocardial infarct size regardless of model type (either in vivo or ex vivo) and reperfusion time (either ≤ 4 h or >4 h).

Conclusion

Coenzyme Q₁₀ significantly decreased myocardial infarct size by 11.36% compared with the control group in animal models of myocardial I/R injury. This beneficial action was retained regardless of model type and reperfusion time.

Improved cardiovascular health by supplementation with selenium and coenzyme Q10: applying structural equation modelling (SEM) to clinical outcomes and biomarkers to explore underlying mechanisms in a prospective randomized double-blind placebo-controlled intervention project in Sweden

Purpose

Selenium and coenzyme Q10 have synergistic antioxidant functions. In a four-year supplemental trial in elderly Swedes with a low selenium status, we found improved cardiac function, less cardiac wall tension and reduced cardiovascular mortality up to 12 years of follow-up. Here we briefly review the main results, including those from studies on biomarkers related to cardiovascular risk that were subsequently conducted. In an effort, to explain underlying mechanisms, we conducted a structured analysis of the inter-relationship between biomarkers.

Methods

Selenium yeast (200 µg/day) and coenzyme Q10 (200 mg/ day), or placebo was given to 443 elderly community-living persons, for 48 months. Structural Equation Modelling (SEM) was used to investigate the statistical inter-relationships between biomarkers related to inflammation, oxidative stress, insulin-like growth factor 1, expression of microRNA, fibrosis, and endothelial dysfunction and their impact on the clinical effects. The main study was registered at Clinicaltrials.gov at 30th of September 2011, and has the identifier NCT01443780.

Results

In addition to positive clinical effects, the intervention with selenium and coenzyme Q10 was also associated with favourable effects on biomarkers of cardiovascular risk. Using these results in the SEM model, we showed that the weights of the first-order factors inflammation and oxidative stress were high, together forming a second-order factor inflammation/oxidative stress influencing the factors, fibrosis (β = 0.74; p < 0.001) and myocardium (β = 0.65; p < 0.001). According to the model, the intervention impacted fibrosis and myocardium through these factors, resulting in improved cardiac function and reduced CV mortality.

Conclusion

Selenium reduced inflammation and oxidative stress. According to the SEM analysis, these effects reduced fibrosis and improved myocardial function pointing to the importance of supplementation in those low on selenium and coenzyme Q10.

Does Coenzyme Q10 Plus Selenium Supplementation Ameliorate Clinical Outcomes by Modulating Oxidative Stress and Inflammation in Individuals with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome?

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a neuroinflammatory, multifaceted chronic disorder of unknown cause. Accumulating data indicate a link between a redox imbalance, mitochondrial dysfunction, and inflammation status in ME/CFS. Coenzyme Q10 (CoQ10) and selenium as effective antioxidant and anti-inflammatory agents have shown potential clinical implications in chronic diseases; however, their therapeutic benefits in ME/CFS remain elusive. This open-label exploratory study aimed to evaluate the effectiveness of combined CoQ10 plus selenium supplementation on clinical features and circulating biomarkers in ME/CFS. Twenty-seven ME/CFS patients received an oral combination of 400 mg of CoQ10 and 200 μg of selenium daily for 8 weeks. The primary endpoint was patient-reported changes in outcome measures from baseline to 8 weeks' postintervention. Secondary endpoint included changes in circulating biomarkers from baseline to each participant. After an 8-week intervention, a significant improvement was found for overall fatigue severity (p = 0.021) and global quality of life (p = 0.002), while there was no significant effect on the sleep disturbances (p = 0.480) among participants. After 8 week's intervention, there was significantly increased total antioxidant capacity, and there were reduced lipoperoxide levels from the participants (p < 0.0001 for both). Circulating cytokine levels decreased significantly (p < 0.01 for all), but with no significant changes in the C-reactive protein, FGF21, and NT-proBNP biomarkers after supplementation. Based on these findings, we hypothesized that long-term supplementation of combined CoQ10 and selenium may indicate a potentially beneficial synergistic effect in ME/CFS. Antioxid. Redox Signal. 36, 729-739.

Sex-Dependent Protective Effect of Combined Application of Solubilized Ubiquinol and Selenium on Monocrotaline-Induced Pulmonary Hypertension in Wistar Rats

Ubiquinol exhibits anti-inflammatory and antioxidant properties. Selenium is a part of a number of antioxidant enzymes. The monocrotaline inducible model of pulmonary hypertension used in this study includes pathological links that may act as an application for the use of ubiquinol with high bioavailability and selenium metabolic products. On day 1, male and female rats were subcutaneously injected with a water-alcohol solution of monocrotaline or only water-alcohol solution. On days 7 and 14, some animals were intravenously injected with either ubiquinol’s vehicle or solubilized ubiquinol, or orally with selenium powder daily, starting from day 7, or received both ubiquinol + selenium. Magnetic resonance imaging of the lungs was performed on day 20. Hemodynamic parameters and morphometry were measured on day 22. An increased right ventricle systolic pressure in relation to control was demonstrated in all groups of animals of both sexes, except the group of males receiving the combination of ubiquinol + selenium. The relative mass of the right ventricle did not differ from the control in all groups of males and females receiving either ubiquinol alone or the combination. Magnetic resonance imaging revealed impaired perfusion in almost all animals examined, but pulmonary fibrosis developed in only half of the animals in the ubiquinol group. Intravenous administration of ubiquinol has a protective effect on monocrotaline-induced pulmonary hypertension development resulting in reduced right ventricle hypertrophy, and lung mass. Ubiquinol + selenium administration resulted in a less severe increase in the right ventricle systolic pressure in male rats but not in females 3 weeks after the start of the experiment. This sex-dependent effect was not observed in the influence of ubiquinol alone.

Decreased Concentration of Fibroblast Growth Factor 23 (FGF-23) as a Result of Supplementation with Selenium and Coenzyme Q10 in an Elderly Swedish Population: A Sub-Analysis

There is a reduced intake of selenium in many countries due to low levels of selenium in the soil. This results in an increased cardiovascular risk. Fibroblast growth factor 23 (FGF-23) is active mainly in the metabolism of vitamin D and phosphorus. However, there are indications that FGF-23 may also provide information both on cardiovascular function and prognosis. The aim of the study was to evaluate the effect of supplementation with selenium and coenzyme Q₁₀ on the FGF-23 concentration in an elderly population with low concentrations of both selenium and coenzyme Q₁₀ and in which the supplementation improved cardiac function and mortality. In a randomised double-blind placebo-controlled trial, FGF-23 was measured in 219 individuals at the start and after 48 months. Selenium yeast (200 µg/day) and coenzyme Q₁₀ (200 mg/day) (n = 118) or placebo (n = 101) were given as a dietary supplement. The intervention time was 48 months. t-Tests, repeated measures of variance, and ANCOVA analyses were used to evaluate the differences in FGF-23 concentration. Following supplementation with selenium and coenzyme Q₁₀, a significantly lower level of FGF-23 could be seen (p = 0.01). Applying 10 years of follow-up, those who later died a cardiovascular death had a significantly higher FGF-23 concentration after 48 months compared with those who survived (p = 0.036), and a significantly lower FGF-23 concentration could be seen in those with a normal renal function compared to those with an impaired renal function (p = 0.027). Supplementation with selenium and coenzyme Q₁₀ to an elderly community-living population low in both substances prevented an increase of FGF-23 and also provided a reduced cardiovascular risk.

Coenzyme Q10 to manage chronic heart failure with a reduced ejection fraction: a systematic review and economic evaluation

BACKGROUND

Chronic heart failure is a debilitating condition that accounts for an annual NHS spend of £2.3B. Low levels of endogenous coenzyme Q10 may exacerbate chronic heart failure. Coenzyme Q10 supplements might improve symptoms and slow progression. As statins are thought to block the production of coenzyme Q10, supplementation might be particularly beneficial for patients taking statins.

OBJECTIVES

To assess the clinical effectiveness and cost-effectiveness of coenzyme Q10 in managing chronic heart failure with a reduced ejection fraction.

METHODS

A systematic review that included randomised trials comparing coenzyme Q10 plus standard care with standard care alone in chronic heart failure. Trials restricted to chronic heart failure with a preserved ejection fraction were excluded. Databases including MEDLINE, EMBASE and CENTRAL were searched up to March 2020. Risk of bias was assessed using the Cochrane Risk of Bias tool (version 5.2). A planned individual participant data meta-analysis was not possible and meta-analyses were mostly based on aggregate data from publications. Potential effect modification was examined using meta-regression. A Markov model used treatment effects from the meta-analysis and baseline mortality and hospitalisation from an observational UK cohort. Costs were evaluated from an NHS and Personal Social Services perspective and expressed in Great British pounds at a 2019/20 price base. Outcomes were expressed in quality-adjusted life-years. Both costs and outcomes were discounted at a 3.5% annual rate.

RESULTS

A total of 26 trials, comprising 2250 participants, were included in the systematic review. Many trials were reported poorly and were rated as having a high or unclear risk of bias in at least one domain. Meta-analysis suggested a possible benefit of coenzyme Q10 on all-cause mortality (seven trials, 1371 participants; relative risk 0.68, 95% confidence interval 0.45 to 1.03). The results for short-term functional outcomes were more modest or unclear. There was no indication of increased adverse events with coenzyme Q10. Meta-regression found no evidence of treatment interaction with statins. The base-case cost-effectiveness analysis produced incremental costs of £4878, incremental quality-adjusted life-years of 1.34 and an incremental cost-effectiveness ratio of £3650. Probabilistic sensitivity analyses showed that at thresholds of £20,000 and £30,000 per quality-adjusted life-year coenzyme Q10 had a high probability (95.2% and 95.8%, respectively) of being more cost-effective than standard care alone. Scenario analyses in which the population and other model assumptions were varied all found coenzyme Q10 to be cost-effective. The expected value of perfect information suggested that a new trial could be valuable.

LIMITATIONS

For most outcomes, data were available from few trials and different trials contributed to different outcomes. There were concerns about risk of bias and whether or not the results from included trials were applicable to a typical UK population. A lack of individual participant data meant that planned detailed analyses of effect modifiers were not possible.

CONCLUSIONS

Available evidence suggested that, if prescribed, coenzyme Q10 has the potential to be clinically effective and cost-effective for heart failure with a reduced ejection fraction. However, given important concerns about risk of bias, plausibility of effect sizes and applicability of the evidence base, establishing whether or not coenzyme Q10 is genuinely effective in a typical UK population is important, particularly as coenzyme Q10 has not been subject to the scrutiny of drug-licensing processes. Stronger evidence is needed before considering its prescription in the NHS.

FUTURE WORK

A new independent, well-designed clinical trial of coenzyme Q10 in a typical UK heart failure with a reduced ejection fraction population may be warranted.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42018106189.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 4. See the NIHR Journals Library website for further project information.

Mitochondrial dysfunction and mitochondrial therapies in heart failure

Cardiovascular diseases remain the leading cause of death worldwide in the last decade, accompanied by immense health and economic burdens. Heart failure (HF), as the terminal stage of many cardiovascular diseases, is a common, intractable, and costly medical condition. Despite significant improvements in pharmacologic and device therapies over the years, life expectancy for this disease remains poor. Current therapies have not reversed the trends in morbidity and mortality as expected. Thus, there is an urgent need for novel potential therapeutic agents. Although the pathophysiology of the failing heart is extraordinarily complex, targeting mitochondrial dysfunction can be an effective approach for potential treatment. Increasing evidence has shown that mitochondrial abnormalities, including altered metabolic substrate utilization, impaired mitochondrial oxidative phosphorylation (OXPHOS), increased reactive oxygen species (ROS) formation, and aberrant mitochondrial dynamics, are closely related to HF. Here, we reviewed the findings on the role of mitochondrial dysfunction in HF, along with novel mitochondrial therapeutics and their pharmacological effects.

Serum Zinc and Selenium Concentrations in Patients with Hypertrophy and Remodelling of the Left Ventricle Secondary to Arterial Hypertension

The aim of the study was to assess the relationship between serum selenium and zinc concentrations (Se-S and Zn-S) and the left ventricle geometry in patients suffering from arterial hypertension. A total of 78 people with arterial hypertension (mean age: 53.72 ± 12.74 years) participated in the study. Se-S and Zn-S were determined in all patients. The type of left ventricular remodelling and hypertrophy was determined by the left ventricular mass index (LVMI) and relative wall thickness (RWT) measured by echocardiography. Se-S and Zn-S in the whole group were 89.84 ± 18.75 µg/L and 0.86 ± 0.13 mg/L. Normal left ventricular geometry was found in 28.2% of patients; left ventricular hypertrophy (LVH) in 71.8%, including concentric remodelling in 28.2%, concentric hypertrophy in 29.5%, and eccentric hypertrophy in 14.1%. LVH was statistically significantly more frequent in patients with Se-S < median compared to patients with Se-S ≥ median (87.2% vs. 56.4%, p < 0.05), as well as in patients with Zn-S < median compared to patients with Zn-S ≥ median (83.8% vs. 60.9%, p < 0.05). In hypertensive patients, older age, higher LDL cholesterol, higher fasting glucose, lower Se-S, and lower Zn-S were independently associated with LVH. In conclusion, in hypertensive patients, left ventricular hypertrophy may be associated with low levels of selenium and zinc in the serum.

Coenzyme Q at the Hinge of Health and Metabolic Diseases

Coenzyme Q is a unique lipidic molecule highly conserved in evolution and essential to maintaining aerobic metabolism. It is endogenously synthesized in all cells by a very complex pathway involving a group of nuclear genes that share high homology among species. This pathway is tightly regulated at transcription and translation, but also by environment and energy requirements. Here, we review how coenzyme Q reacts within mitochondria to promote ATP synthesis and also integrates a plethora of metabolic pathways and regulates mitochondrial oxidative stress. Coenzyme Q is also located in all cellular membranes and plasma lipoproteins in which it exerts antioxidant function, and its reaction with different extramitochondrial oxidoreductases contributes to regulate the cellular redox homeostasis and cytosolic oxidative stress, providing a key factor in controlling various apoptosis mechanisms. Coenzyme Q levels can be decreased in humans by defects in the biosynthesis pathway or by mitochondrial or cytosolic dysfunctions, leading to a highly heterogeneous group of mitochondrial diseases included in the coenzyme Q deficiency syndrome. We also review the importance of coenzyme Q levels and its reactions involved in aging and age-associated metabolic disorders, and how the strategy of its supplementation has had benefits for combating these diseases and for physical performance in aging.

Impact of Selenium on Biomarkers and Clinical Aspects Related to Ageing. A Review

Selenium (Se) is an essential dietary trace element that plays an important role in the prevention of inflammation, cardiovascular diseases, infections, and cancer. Selenoproteins contain selenocysteine in the active center and include, i.a., the enzymes thioredoxin reductases (TXNRD1–3), glutathione peroxidases (GPX1–4 and GPX6) and methionine sulfoxide reductase, involved in immune functions, metabolic homeostasis, and antioxidant defense. Ageing is an inevitable process, which, i.a., involves an imbalance between antioxidative defense and reactive oxygen species (ROS), changes in protein and mitochondrial renewal, telomere attrition, cellular senescence, epigenetic alterations, and stem cell exhaustion. These conditions are associated with mild to moderate inflammation, which always accompanies the process of ageing and age-related diseases. In older individuals, Se, by being a component in protective enzymes, operates by decreasing ROS-mediated inflammation, removing misfolded proteins, decreasing DNA damage, and promoting telomere length. Se-dependent GPX1–4 and TXNRD1–3 directly suppress oxidative stress. Selenoprotein H in the cell nucleus protects DNA, and selenoproteins residing in the endoplasmic reticulum (ER) assist in the removal of misfolded proteins and protection against ER stress. In this review, we highlight the role of adequate Se status for human ageing and prevention of age-related diseases, and further its proposed role in preservation of telomere length in middle-aged and elderly individuals.

Effects of Selenium treatment on cardiac function in Chagas heart disease: Results from the STCC randomized Trial

BACKGROUND

Chagas disease (caused by Trypanosoma cruzi infection) evolves to chronic chagasic cardiomyopathy (CCC) affecting 1.8 million people worldwide. This is the first randomized, placebo-controlled, double-blinded, clinical trial designed to estimate efficacy and safety of selenium (Se) treatment in CCC.

METHODS

66 patients with CCC stages B1 (left ventricular ejection fraction [LVEF] > 45% and no heart failure; n = 54) or B2 (LVEF < 45% and no heart failure; n = 12) were randomly assigned to receive 100 mcg/day sodium selenite (Se, n = 32) or placebo (Pla, n = 34) for one year (study period: May 2014-September 2018). LVEF changes over time and adverse effects were investigated. Trial registration number: NCT00875173 (clinicaltrials.gov).

FINDINGS

No significant differences between the two groups were observed for the primary outcome: mean LVEF after 6 (β= +1.1 p = 0.51 for Se vs Pla) and 12 months (β= +2.1; p = 0.23). In a subgroup analysis, statistically significant longitudinal changes were observed for mean LVEF in the stage B2 subgroup (β= +10.1; p = 0.02 for Se [n = 4] vs Pla [n = 8]). Se treatment was safe for CCC patients, and the few adverse effects observed were similarly distributed across the two groups.

INTERPRETATION

Se treatment did not improve cardiac function (evaluated from LVEF) in CCC. However, in the subgroup of patients at B2 stage, a potential beneficial influence of Se was observed. Complementary studies are necessary to explore diverse Se dose and/or associations in different CCC stages (B2 and C), as well as in A and B1 stages with longer follow-up.

FUNDING

Brazilian Ministry of Health, Fiocruz, CNPq, FAPERJ.

Selenium, Selenoproteins, and Heart Failure: Current Knowledge and Future Perspective

PURPOSE OF REVIEW

(Mal-)nutrition of micronutrients, like selenium, has great impact on the human heart and improper micronutrient intake was observed in 30-50% of patients with heart failure. Low selenium levels have been reported in Europe and Asia and thought to be causal for Keshan disease. Selenium is an essential micronutrient that is needed for enzymatic activity of the 25 so-called selenoproteins, which have a broad range of activities. In this review, we aim to summarize the current evidence about selenium in heart failure and to provide insights about the potential mechanisms that can be modulated by selenoproteins.

RECENT FINDINGS

Suboptimal selenium levels (<100 μg/L) are prevalent in more than 70% of patients with heart failure and were associated with lower exercise capacity, lower quality of life, and worse prognosis. Small clinical trials assessing selenium supplementation in patients with HF showed improvement of clinical symptoms (NYHA class), left ventricular ejection fraction, and lipid profile, while governmental interventional programs in endemic areas have significantly decreased the incidence of Keshan disease. In addition, several selenoproteins are found impaired in suboptimal selenium conditions, potentially aggravating underlying mechanisms like oxidative stress, inflammation, and thyroid hormone insufficiency. While the current evidence is not sufficient to advocate selenium supplementation in patients with heart failure, there is a clear need for high level evidence to show whether treatment with selenium has a place in the contemporary treatment of patients with HF to improve meaningful clinical endpoints. Graphical summary summarizing the potential beneficial effects of the various selenoproteins, locally in cardiac tissues and systemically in the rest of the body. In short, several selenoproteins contribute in protecting the integrity of the mitochondria. By doing so, they contribute indirectly to reducing the oxidative stress as well as improving the functionality of immune cells, which are in particular vulnerable to oxidative stress. Several other selenoproteins are directly involved in antioxidative pathways, next to excreting anti-inflammatory effects. Similarly, some selenoproteins are located in the endoplasmic reticulum, playing roles in protein folding. With exception of the protection of the mitochondria and the reduction of oxidative stress, other effects are not yet investigated in cardiac tissues. The systemic effects of selenoproteins might not be limited to these mechanisms, but also may include modulation of endothelial function, protection skeletal muscles, in addition to thyroid metabolism.

ABBREVIATIONS

DIO, iodothyronine deiodinase; GPx, glutathione peroxidase; MsrB2, methionine-R-sulfoxide reductase B2; SELENOK, selenoprotein K; SELENON, selenoprotein N; SELENOP, selenoprotein P; SELENOS, selenoprotein S; SELENOT, selenoprotein T; TXNRD, thioredoxin reductase.

Food Sources of Selenium and Its Relationship with Chronic Diseases

Selenium (Se) is an essential micronutrient for mammals, and its deficiency seriously threatens human health. A series of biofortification strategies have been developed to produce Se-enriched foods for combating Se deficiency. Although there have been some inconsistent results, extensive evidence has suggested that Se supplementation is beneficial for preventing and treating several chronic diseases. Understanding the association between Se and chronic diseases is essential for guiding clinical practice, developing effective public health policies, and ultimately counteracting health issues associated with Se deficiency. The current review will discuss the food sources of Se, biofortification strategies, metabolism and biological activities, clinical disorders and dietary reference intakes, as well as the relationship between Se and health outcomes, especially cardiovascular disease, diabetes, chronic inflammation, cancer, and fertility. Additionally, some concepts were proposed, there is a non-linear U-shaped dose-responsive relationship between Se status and health effects: subjects with a low baseline Se status can benefit from Se supplementation, while Se supplementation in populations with an adequate or high status may potentially increase the risk of some diseases. In addition, at supra-nutritional levels, methylated Se compounds exerted more promising cancer chemo-preventive efficacy in preclinical trials.

L-Carnosine Stimulation of Coenzyme Q10 Biosynthesis Promotes Improved Mitochondrial Function and Decreases Hepatic Steatosis in Diabetic Conditions

Mitochondrial dysfunction in type 2 diabetes leads to oxidative stress, which drives disease progression and diabetes complications. L-carnosine, an endogenous dipeptide, improves metabolic control, wound healing and kidney function in animal models of type 2 diabetes. Coenzyme Q (CoQ), a component of the mitochondrial electron transport chain, possesses similar protective effects on diabetes complications. We aimed to study the effect of carnosine on CoQ, and assess any synergistic effects of carnosine and CoQ on improved mitochondrial function in a mouse model of type 2 diabetes. Carnosine enhanced CoQ gene expression and increased hepatic CoQ biosynthesis in db/db mice, a type 2 diabetes model. Co-administration of Carnosine and CoQ improved mitochondrial function, lowered ROS formation and reduced signs of oxidative stress. Our work suggests that carnosine exerts beneficial effects on hepatic CoQ synthesis and when combined with CoQ, improves mitochondrial function and cellular redox balance in the liver of diabetic mice. (4) Conclusions: L-carnosine has beneficial effects on oxidative stress both alone and in combination with CoQ on hepatic mitochondrial function in an obese type 2 diabetes mouse model.

Coenzyme Q10 and Immune Function: An Overview

Coenzyme Q10 (CoQ10) has a number of important roles in the cell that are required for optimal functioning of the immune system. These include its essential role as an electron carrier in the mitochondrial respiratory chain, enabling the process of oxidative phosphorylation to occur with the concomitant production of ATP, together with its role as a potential lipid-soluble antioxidant, protecting the cell against free radical-induced oxidation. Furthermore, CoQ10 has also been reported to have an anti-inflammatory role via its ability to repress inflammatory gene expression. Recently, CoQ10 has also been reported to play an important function within the lysosome, an organelle central to the immune response. In view of the differing roles CoQ10 plays in the immune system, together with the reported ability of CoQ10 supplementation to improve the functioning of this system, the aim of this article is to review the current literature available on both the role of CoQ10 in human immune function and the effect of CoQ10 supplementation on this system.

The Use of Coenzyme Q10 in Cardiovascular Diseases

CoQ10 is an endogenous antioxidant produced in all cells that plays an essential role in energy metabolism and antioxidant protection. CoQ10 distribution is not uniform among different organs, and the highest concentration is observed in the heart, though its levels decrease with age. Advanced age is the major risk factor for cardiovascular disease and endothelial dysfunction triggered by oxidative stress that impairs mitochondrial bioenergetic and reduces NO bioavailability, thus affecting vasodilatation. The rationale of the use of CoQ10 in cardiovascular diseases is that the loss of contractile function due to an energy depletion status in the mitochondria and reduced levels of NO for vasodilatation has been associated with low endogenous CoQ10 levels. Clinical evidence shows that CoQ10 supplementation for prolonged periods is safe, well-tolerated and significantly increases the concentration of CoQ10 in plasma up to 3–5 µg/mL. CoQ10 supplementation reduces oxidative stress and mortality from cardiovascular causes and improves clinical outcome in patients undergoing coronary artery bypass graft surgery, prevents the accumulation of oxLDL in arteries, decreases vascular stiffness and hypertension, improves endothelial dysfunction by reducing the source of ROS in the vascular system and increases the NO levels for vasodilation.

Non-alcoholic fatty liver and chronic kidney disease: Retrospect, introspect, and prospect

With the growing prevalence of obesity and diabetes in the United States and across the world, a rise in the overall incidence and prevalence of non-alcoholic fatty liver disease (NAFLD) is expected. The risk factors for NAFLD are also associated with the development of chronic kidney disease (CKD). We review the epidemiology, risk factors, genetics, implications of gut dysbiosis, and specific pathogenic mechanisms linking NAFLD to CKD. Mechanisms such as ectopic lipid accumulation, cellular signaling abnormalities, and the interplay between fructose consumption and uric acid accumulation have led to the emergence of potential therapeutic implications for this patient population. Transplant evaluation in the setting of both NAFLD and CKD is also reviewed. Potential strategies for surveillance and management include the monitoring of comorbidities, the use of non-invasive fibrosis scoring systems, and the measurement of laboratory markers. Lastly, we discuss the management of patients with NAFLD and CKD, from preventative measures to experimental interventions.

Effects of Fish Oil Combined with Selenium and Zinc on Learning and Memory Impairment in Aging Mice and Amyloid Precursor Protein Processing

Alzheimer's disease is characterized by the aggregation of amyloid-beta (Aβ) peptide into plaques and neurofibrillary tangles. Aβ peptide is generated by the cleavage of the β-amyloid precursor protein (APP) by β- and γ-secretase. The present study was conducted to investigate the effects of fish oil (or eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)), selenium, and zinc on learning and memory impairment in an aging mouse model and on APP. We performed the Morris water maze and platform recorder tests on male Kunming mice (10/group) grouped as control and D-galactose-induced aging model mice treated with vehicle, fish oil, fish oil + selenium, fish oil + selenium + zinc, and positive control (red ginseng extract). Fish oil + zinc + selenium for 7 weeks significantly improved learning and memory impairments in aging model animals in the Morris water maze and platform recorder tests, as evidenced by shortened incubation periods and number of errors. In vitro analysis of Aβ_1-40 content in APP695-transfected CHO cells revealed a decrease after treatment with EPA, DHA, and their combinations with selenium or selenium and zinc. Assaying β- and γ-secretase activities revealed a decrease in PC₁₂ cells and mouse serum as well as a decrease in β-site APP-cleaving enzyme 1 and presenilin 1 protein levels in the PC₁₂ cells and mouse serum. Taken together, our results show that fish oil combined with selenium and zinc inhibited APP processing and alleviated learning and memory impairment in a mouse model of aging.

Dietary Supplementation with Selenium and Coenzyme Q10 Prevents Increase in Plasma D-Dimer While Lowering Cardiovascular Mortality in an Elderly Swedish Population

A low intake of selenium is associated with increased cardiovascular mortality. This could be reduced by supplementation with selenium and coenzyme Q₁₀. D-dimer, a fragment of fibrin mirroring fibrinolysis, is a biomarker of thromboembolism, increased inflammation, endothelial dysfunction and is associated with cardiovascular mortality in ischemic heart disease. The objective was to examine the impact of selenium and coenzyme Q₁₀ on the level of D-dimer, and its relationship to cardiovascular mortality. D-dimer was measured in 213 individuals at the start and after 48 months of a randomised double-blind placebo-controlled trial with selenium yeast (200 µg/day) and coenzyme Q₁₀ (200 mg/day) (n = 106) or placebo (n = 107). The follow-up time was 4.9 years. All included individuals were low in selenium (mean 67 μg/L, SD 16.8). The differences in D-dimer concentration were evaluated by the use of T-tests, repeated measures of variance and ANCOVA analyses. At the end, a significantly lower D-dimer concentration was observed in the active treatment group in comparison with those on placebo (p = 0.006). Although D-dimer values at baseline were weakly associated with high-sensitive CRP, while being more strongly associated with soluble tumour necrosis factor receptor 1 and sP-selectin, controlling for these in the analysis there was an independent effect on D-dimer. In participants with a D-dimer level above median at baseline, the supplementation resulted in significantly lower cardiovascular mortality compared to those on placebo (p = 0.014). All results were validated with a persisting significant difference between the two groups. Therefore, supplementation with selenium and coenzyme Q₁₀ in a group of elderly low in selenium and coenzyme Q₁₀ prevented an increase in D-dimer and reduced the risk of cardiovascular mortality in comparison with the placebo group. The obtained results also illustrate important associations between inflammation, endothelial function and cardiovascular risk.

Nutraceutical, Dietary, and Lifestyle Options for Prevention and Treatment of Ventricular Hypertrophy and Heart Failure

Although well documented drug therapies are available for the management of ventricular hypertrophy (VH) and heart failure (HF), most patients nonetheless experience a downhill course, and further therapeutic measures are needed. Nutraceutical, dietary, and lifestyle measures may have particular merit in this regard, as they are currently available, relatively safe and inexpensive, and can lend themselves to primary prevention as well. A consideration of the pathogenic mechanisms underlying the VH/HF syndrome suggests that measures which control oxidative and endoplasmic reticulum (ER) stress, that support effective nitric oxide and hydrogen sulfide bioactivity, that prevent a reduction in cardiomyocyte pH, and that boost the production of protective hormones, such as fibroblast growth factor 21 (FGF21), while suppressing fibroblast growth factor 23 (FGF23) and marinobufagenin, may have utility for preventing and controlling this syndrome. Agents considered in this essay include phycocyanobilin, N-acetylcysteine, lipoic acid, ferulic acid, zinc, selenium, ubiquinol, astaxanthin, melatonin, tauroursodeoxycholic acid, berberine, citrulline, high-dose folate, cocoa flavanols, hawthorn extract, dietary nitrate, high-dose biotin, soy isoflavones, taurine, carnitine, magnesium orotate, EPA-rich fish oil, glycine, and copper. The potential advantages of whole-food plant-based diets, moderation in salt intake, avoidance of phosphate additives, and regular exercise training and sauna sessions are also discussed. There should be considerable scope for the development of functional foods and supplements which make it more convenient and affordable for patients to consume complementary combinations of the agents discussed here. Research Strategy: Key word searching of PubMed was employed to locate the research papers whose findings are cited in this essay.

COVID-19, Coenzyme Q10 and Selenium

In COVID-19 infection, a balance must be achieved in immune defence against the virus without precipitating a cytokine storm, which is responsible for lung injury and respiratory distress in severe cases. The initial immune response and the subsequent resolution of inflammation are likely to be dependent on nutritional status, as one contributing factor. Here, we have reviewed the potential link between two specific nutrients, coenzyme Q10 (CoQ10) and selenium, with effects on oxidative stress and inflammation in viral infection. We conclude that both reagents show promise in the treatment of patients with COVID-19 disease. This could give particular relevance over the next several months as promising vaccines are deployed to minimise the COVID-19 spread and as a potential preventative or mitigating approach for future epidemics and pandemics.

Selenium and Coenzyme Q10 Supplementation Improves Renal Function in Elderly Deficient in Selenium: Observational Results and Results from a Subgroup Analysis of a Prospective Randomised Double-Blind Placebo-Controlled Trial

A low selenium intake is found in European countries, and is associated with increased cardiovascular mortality. There is an association between selenium level and the severity of kidney disease. An association between inflammation and selenium intake is also reported. The coenzyme Q10 level is decreased in kidney disease. The aim of this study was to examine a possible association between selenium and renal function in an elderly population low in selenium and coenzyme Q₁₀, and the impact of intervention with selenium and coenzyme Q₁₀ on the renal function. The association between selenium status and creatinine was studied in 589 elderly persons. In 215 of these (mean age 71 years) a randomised double-blind placebo-controlled prospective trial with selenium yeast (200 µg/day) and coenzyme Q₁₀ (200 mg/day) (n = 117) or placebo (n = 98) was conducted. Renal function was determined using measures of glomerular function at the start and after 48 months. The follow-up time was 5.1 years. All individuals were low on selenium (mean 67 μg/L (SD 16.8)). The changes in renal function were evaluated by measurement of creatinine, cystatin-C, and the use of the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) algorithm, and by the use of T-tests, repeated measures of variance and ANCOVA analyses. An association between low selenium status and impaired renal function was observed. Intervention causes a significantly lower serum creatinine, and cystatin-C concentration in the active treatment group compared with those on placebo (p = 0.0002 and p = 0.001 resp.). The evaluation with CKD-EPI based on both creatinine and cystatin-C showed a corresponding significant difference (p < 0.0001). All validations showed corresponding significant differences. In individuals with a deficiency of selenium and coenzyme Q_10, low selenium status is related to impaired renal function, and thus supplementation with selenium and coenzyme Q10 results in significantly improved renal function as seen from creatinine and cystatin-C and through the CKD-EPI algorithm. The explanation could be related to positive effects on inflammation and oxidative stress as a result of the supplementation.

Statin Treatment in Specific Patient Groups: Role for Improved Cardiovascular Risk Markers

Ample evidence supports the use of statin therapy for secondary prevention in patients with a history of atherosclerotic cardiovascular disease (ASCVD), but evidence is wanting in the case of primary prevention, low-risk individuals, and elderly adults 65+. Statins are effective in lowering low-density lipoprotein (LDL), which has long been a target for treatment decisions. We discuss the weakening dependence between cholesterol levels and mortality as a function of age and highlight recent findings on lipoprotein subfractions and other superior markers of ASCVD risk. The efficacy of statins is compared for distinct subsets of patients based on age, diabetes, ASCVD, and coronary artery calcium (CAC) status. Most cardiovascular risk calculators heavily weight age and overestimate one's absolute risk of ASCVD, particularly in very old adults. Improvements in risk assessment enable the identification of specific patient populations that benefit most from statin treatment. Derisking is particularly important for adults over 75, in whom treatment benefits are reduced and adverse musculoskeletal effects are amplified. The CAC score stratifies the benefit effect size obtainable with statins, and forms of coenzyme Q are discussed for improving patient outcomes. Robust risk estimator tools and personalized, evidence-based approaches are needed to optimally reduce cardiovascular events and mortality rates through administration of cholesterol-lowering medications.

Low coenzyme Q10 levels in patients with acute cardiovascular disease are associated with long-term mortality

Coenzyme Q10 (CoQ10) plays a potential role in the prevention and treatment of cardiovascular disease through improved cellular bioenergetics. Critical illness in the intensive care unit has been reported to be associated with decreased circulating CoQ10 levels, and we previously demonstrated the association of low CoQ10 levels with in-hospital mortality. However, the association of CoQ10 with the acute phase of cardiovascular disease and long-term mortality remains unclear. We enrolled 242 consecutive patients with cardiovascular disease admitted to the coronary care unit of Juntendo University Hospital to investigate the association between long-term mortality and serum CoQ10 levels. During a mean follow-up of 3.2 years, 58 patients died. The mean serum CoQ10 levels were significantly lower in the non-survivors than in the survivors (0.48 ± 0.27 vs. 0.58 ± 0.38 mg/L; p = 0.035). Compared with the patients with above-median CoQ10 levels (0.46 mg/L), the cumulative incidence of all-cause mortality was significantly higher in those with lower CoQ10 levels (p = 0.025). Multivariate Cox regression analysis further demonstrated that lower CoQ10 levels were associated with poor prognosis. Low serum CoQ10 levels during the acute phase of cardiovascular diseases were associated with long-term mortality in patients, suggesting the utility of low serum CoQ10 levels as a predictor and potential therapeutic target.

A Clinical Tool to Predict Low Serum Selenium in Patients with Worsening Heart Failure

Selenium is an essential micronutrient, and a low selenium concentration (<100 µg/L) is associated with a poorer quality of life and exercise capacity, and an impaired prognosis in patients with worsening heart failure. Measuring selenium concentrations routinely is laborious and costly, and although its clinical utility is yet to be proven, an easy implemented model to predict selenium status is desirable. A stepwise multivariable logistic regression analysis was performed using routinely measured clinical factors. Low selenium was independently predicted by: older age, lower serum albumin, higher N-terminal pro-B-type natriuretic peptide levels, worse kidney function, and the presence of orthopnea and iron deficiency. A 10-points risk-model was developed, and a score of ≥6 points identified >80% of patients with low selenium (sensitivity of 44%, specificity of 80%). Given that selenium and iron overlap in their physiological roles, we evaluated the shared determinants and prognostic associates. Both deficiencies shared similar clinical characteristics, including the model risk factors and, in addition, a low protein intake and high levels of C-reactive protein. Low selenium was associated with a similar or worse prognosis compared to iron deficiency. In conclusion, although it is difficult to exclude low selenium based on clinical characteristics alone, we provide a prediction tool which identifies heart failure patients at higher risk of having a low selenium status.

Bioavailability of Coenzyme Q10: An Overview of the Absorption Process and Subsequent Metabolism

A lack of understanding of the processes determining the absorption and subsequent metabolism of coenzyme Q₁₀ (CoQ₁₀) has resulted in some manufacturers’ making incorrect claims regarding the bioavailability of their CoQ₁₀ supplements, with potential consequences for the use of such products in clinical trials. The purpose of the present review article is, therefore, to describe the various stages of exogenous CoQ₁₀ metabolism, from its first ingestion, stomach transit, absorption from the small intestine into the lymphatic system, transport in blood, and access into cells. In particular, the importance of CoQ₁₀ crystal dispersion in the initial formulation is emphasised, the absence of which reduces bioavailability by 75%. In addition, evidence comparing the relative bioavailability and efficacy of ubiquinone and ubiquinol forms of CoQ₁₀ has been reviewed.

Supplemental selenium and coenzyme Q10 reduce glycation along with cardiovascular mortality in an elderly population with low selenium status - A four-year, prospective, randomised, double-blind placebo-controlled trial

BACKGROUND

A low intake of selenium has been shown to increase the risk of cardiovascular mortality, and supplementation of selenium and coenzyme Q10 influences this. The mechanism behind is unclear although effects on inflammation, oxidative stress and microRNA expression have been reported. Fructosamine, a marker of long-term glycaemic control, is also a marker of increased risk of heart disease and death, even in non-diabetics.

OBJECTIVE

To analyse the impact of selenium and coenzyme Q10 supplementation on the concentration of fructosamine. Also, the relation between pre-intervention serum selenium concentration and the effect on fructosamine of the intervention was studied.

METHODS

Fructosamine plasma concentration was determined in 219 participants after six and 42 months of intervention with selenium yeast (200 μg/day) and coenzyme Q10 (200 mg/ day) (n = 118 of which 20 had diabetes at inclusion), or placebo (n = 101 of which 18 had diabetes at inclusion). Pre-intervention, the serum selenium levels were 67 μg/L (active treatment group: 66.6 μg/L; placebo group: 67.4 μg/L), corresponding to an estimated intake of 35 μg/day. Changes in concentrations of fructosamine following intervention were assessed by the use of T-tests, repeated measures of variance, and ANCOVA analyses.

RESULTS

Post-intervention selenium concentrations were 210 μg/L in the active group and 72 μg/L in the placebo group. A lower concentration of fructosamine could be seen as a result of the intervention in the total population (P = 0.001) in both the males (P = 0.04) and in the females (P = 0.01) in the non-diabetic population (P = 0.002), and in both the younger (<76 years) (P = 0.01) and the older (≥76 years) participants (P = 0.03). No difference could be demonstrated in fructosamine concentration in the diabetic patients, but the total sample was small (n = 38). In subjects with a low pre-intervention level of serum selenium the intervention gave a more pronounced decrease in fructosamine compared with those with a higher baseline selenium level.

CONCLUSION

A significantly lower concentration of fructosamine was observed in the elderly community-living participants supplemented with selenium and coenzyme Q10 for 42 months compared to those on the placebo. As oxidative mechanisms are involved in the glycation of proteins, less glycoxidation could be a result of the supplementation of selenium and coenzyme Q10, which could have contributed to lower cardiac mortality and less inflammation, as has earlier been reported. This study was registered at Clinicaltrials.gov, and has the identifier NCT01443780.