Beneficial effect of coenzyme Q10 on increased oxidative and nitrative stress and inflammation and individual metabolic components developing in a rat model of metabolic syndrome

The Scavenging Activity of Coenzyme Q10 Plus a Nutritional Complex on Human Retinal Pigment Epithelial Cells

Age-related macular degeneration (AMD) and diabetic retinopathy (DR) are common retinal diseases responsible for most blindness in working-age and elderly populations. Oxidative stress and mitochondrial dysfunction play roles in these pathogenesis, and new therapies counteracting these contributors could be of great interest. Some molecules, like coenzyme Q10 (CoQ10), are considered beneficial to maintain mitochondrial homeostasis and contribute to the prevention of cellular apoptosis. We investigated the impact of adding CoQ10 (Q) to a nutritional antioxidant complex (Nutrof Total®; N) on the mitochondrial status and apoptosis in an in vitro hydrogen peroxide (H2O2)-induced oxidative stress model in human retinal pigment epithelium (RPE) cells. H2O2 significantly increased 8-OHdG levels (p < 0.05), caspase-3 (p < 0.0001) and TUNEL intensity (p < 0.01), and RANTES (p < 0.05), caspase-1 (p < 0.05), superoxide (p < 0.05), and DRP-1 (p < 0.05) levels, and also decreased IL1β, SOD2, and CAT gene expression (p < 0.05) vs. control. Remarkably, Q showed a significant recovery in IL1β gene expression, TUNEL, TNFα, caspase-1, and JC-1 (p < 0.05) vs. H2O2, and NQ showed a synergist effect in caspase-3 (p < 0.01), TUNEL (p < 0.0001), mtDNA, and DRP-1 (p < 0.05). Our results showed that CoQ10 supplementation is effective in restoring/preventing apoptosis and mitochondrial stress-related damage, suggesting that it could be a valid strategy in degenerative processes such as AMD or DR.

Oxidative Stress, Inflammation, and Mitochondrial Dysfunction: A Link between Obesity and Atrial Fibrillation

The adipose tissue has long been thought to represent a passive source of triglycerides and fatty acids. However, extensive data have demonstrated that the adipose tissue is also a major endocrine organ that directly or indirectly affects the physiological functions of almost all cell types. Obesity is recognized as a risk factor for multiple systemic conditions, including metabolic syndrome, type 2 diabetes mellitus, sleep apnea, cardiovascular disorders, and many others. Obesity-related changes in the adipose tissue induce functional and structural changes in cardiac myocytes, promoting a wide range of cardiovascular disorders, including atrial fibrillation (AF). Due to the wealth of epidemiologic data linking AF to obesity, the mechanisms underlying AF occurrence in obese patients are an area of rich ongoing investigation. However, progress has been somewhat slowed by the complex phenotypes of both obesity and AF. The triad inflammation, oxidative stress, and mitochondrial dysfunction are critical for AF pathogenesis in the setting of obesity via multiple structural and functional proarrhythmic changes at the level of the atria. The aim of this paper is to provide a comprehensive view of the close relationship between obesity-induced oxidative stress, inflammation, and mitochondrial dysfunction and the pathogenesis of AF. The clinical implications of these mechanistic insights are also discussed.

Effects of coconut oil long-term supplementation in Wistar rats during metabolic syndrome - regulation of metabolic conditions involving glucose homeostasis, inflammatory signals, and oxidative stress

This study was designed to evaluate the long-term effects of Fructose (20%) feeding in rats, simulating metabolic syndrome (MetS), and the effects of coconut oil (C.O.) supplementation when administered in a MetS context. MetS is a cluster of systemic conditions that represent an increased chance of developing cardiovascular diseases and type 2 diabetes in the future. C.O. has been the target of media speculation, and recent studies report inconsistent results. C.O. improved glucose homeostasis and reduced fat accumulation in Fructose-fed rats while decreasing the levels of triglycerides (TGs) in the liver. C.O. supplementation also increased TGs levels and fructosamine in serum during MetS, possibly due to white adipose tissue breakdown and high fructose feeding. Pro-inflammatory cytokines IL-1β and TNF-α were also increased in rats treated with Fructose and C.O. Oxidative stress marker nitrotyrosine is increased in fructose-fed animals, and C.O. treatment did not prevent this damage. No significant changes were observed in lipoperoxidation marker 4-Hydroxynonenal; however, fructose feeding increased total conjugated dienes and caused conjugated dienes to switch their conformation from cis-trans to trans-trans, which was not prevented by C.O. treatment. Potential benefits of C.O. have been reported with inconsistent results, and indeed we observed some benefits of C.O. supplementation in aiding weight loss, fat accumulation, and improving glucose homeostasis. Nonetheless, we also demonstrated that long-term C.O. supplementation could present some problematic effects with higher risk for individuals suffering MetS, including increased TGs and fructosamine levels and conformational changes in dienes.

Pediatric obesity and severe asthma: Targeting pathways driving inflammation

Asthma affects more than 300 million people of all ages worldwide, including about 10-15% of school-aged children, and its prevalence is increasing. Severe asthma (SA) is a particular and rare phenotype requiring treatment with high-dose inhaled corticosteroids plus a second controller and/or systemic glucocorticoid courses to achieve symptom control or remaining "uncontrolled" despite this therapy. In SA, other diagnoses have been excluded, and potential exacerbating factors have been addressed. Notably, obese asthmatics are at higher risk of developing SA. Obesity is both a major risk factor and a disease modifier of asthma in children and adults: two main "obese asthma" phenotypes have been described in childhood with high or low levels of Type 2 inflammation biomarkers, respectively, the former characterized by early onset and eosinophilic inflammation and the latter by neutrophilic inflammation and late-onset. Nevertheless, the interplay between obesity and asthma is far more complex and includes obese tissue-driven inflammatory pathways, mechanical factors, comorbidities, and poor response to corticosteroids. This review outlines the most recent findings on SA in obese children, particularly focusing on inflammatory pathways, which are becoming of pivotal importance in order to identify selective targets for specific treatments, such as biological agents.

The therapeutic effects of coenzyme Q10 on surgically induced endometriosis in Sprague Dawley rats

The aim of this study was to evaluate the effects of coenzyme Q10 in the treatment of endometriosis rat models. Twenty seven Sprague Dawley rats were divided into four groups; Control Group (n = 7; Endometriosis group), Reference Group (n = 6; Endometriosis + Buserelin acetate, 20 mg/kg), CoQ10 Group-I (n = 7; Endometriosis + CoQ10, 50 mg/kg) and CoQ10 Group-II (n = 7; Endometriosis + CoQ10, 100 mg/kg). At the end of the experiment, all the rats were sacrificed, and the volume and histoarchitecture of endometrial implants were evaluated. The mast cells were determined by Toluidine blue and collagen fiber density was analysed by Masson's Trichrome staining. Tumour necrosis factor and vascular endothelial growth factor (VEGF) levels were analysed by enzyme-linked immunosorbent assay in peritoneal fluid and VEGF and matrix metalloproteinase-9 (MMP-9) were evaluated by immunohistochemistry. Terminal deoxynucleotidil transferase-mediated dUTP Nick end labelling (TUNEL) was also used for the detection of apoptotic cells. The CoQ10 treatment significantly decreased the volume of endometriotic implants, VEGF, and MMP-9 immunoreactivity and increased TUNEL-positive cells. The findings of the study suggest that CoQ10 can be used in endometriosis treatment by suppressing the endometriotic implants.IMPACT STATEMENTWhat is already known on this subject? Endometriosis is a gynaecological disorder and previous studies have shown that different treatments with antioxidants cause significant regression in the endometriotic implants.What the results of this study add? In this study, CoQ10 reduced intra-abdominal adhesion scores and volume of the endometriotic implants. In addition, CoQ10 treatment affected mast cell, TNF-α, VEGF, and MMP-9.What of these findings for clinical practice and/or further research? CoQ10 treatments may be possible to apply, it can contribute to science in terms of a new therapeutic treatment for endometriosis. Further studies are required to evaluate the Coenzyme Q10's effects on pain and subfertility in endometriosis.

Preclinical and Clinical Role of Coenzyme Q10 Supplementation in Various Pathological States

Coenzyme Q10 (CoQ10) is an efficient antioxidant produced endogenously in a living organism. It acts as an important cofactor in the electron transport system of mitochondria and reported as a safe supplement in humans and animals with minimal adverse effect. CoQ10 is found naturally, as a trans configuration, chemical nomenclature of which is 2,3- dimethoxy-5- methyl-6-decaprenyle -1,4-benzoquinone. It is found in the body in two forms. In quinone form (oxidized form), it serves as an electron transporter that transfers the electrons in the electron transport chain between various complexes, and in ubiquinol form (reduced form), it serves as potent antioxidants by scavenging free radicals or by tocopherol regeneration in the living organism. Its primary roles include synthesis of adenosine triphosphate (ATP), stabilizes lipid membrane, antioxidant activity, cell growth stimulation, and cell death inhibition. CoQ10 has shown a variety of pharmacological and clinical effects including neuroprotective, hepatoprotective, anti-atherosclerotic, anticonvulsant, antidepressant, anti-inflammatory, antinociceptive, cardiovascular, antimicrobial, immunomodulatory, and various effects on the central nervous system. Present review has set about to bring updated information regarding to clinical and preclinical activities of CoQ10, which may be helpful to researchers to explore a new bioactive molecules for various therapeutic application.

Dietary supplementation of hemp oil in teddy dogs: Effect on apparent nutrient digestibility, blood biochemistry and metabolomics

Present study aimed to evaluate the influence of distinct concentration of dietary supplements hemp oil on apparent nutrient digestibility, blood biochemical parameters and metabolomics of teddy dogs. A total of 25 healthy teddy dogs were selected and divided into five treatments according to diet supplements hemp oil at a rate of 0% (A), 0.5% (B), 1% (C), 2% (D), and 4% (E). Appropriate added hemp oil improved apparent nutrient digestibility of dry matter, crude protein and crude fat (86.32–88.08%, 86.87–88.87% and 96.76–97.43%). The hemp oil significantly increased blood biochemical of utilization related total protein, albumin and globulin (61.33–69.54, 35.08–40.38 and 26.53–31.63 g/L), immunity capacity related immunoglobulin E and γ-interferon (203–347kU/L and 23.04–25.78ng/L), energy-related thyroxine and triiodothyronine (27.11–36.75 and 0.94–1.67 nmol/L). In addition, hemp oil improved superoxide dismutation (26.47–33.02 U/ml) and reduced malondialdehyde (5.30–3.28 nmol/ml). The differential metabolites mainly included nucleotides and metabolites of oxidized lipids, bile and other fatty acids, coenzymes and vitamins. The main metabolic pathways included purine and arachidonic acid metabolism, bile and unsaturated fatty acid biosynthesis, cell oxidative phosphorylation and rheumatoid arthritis. Overall, appropriate dietary supplements hemp oil positively to nutrient digestibility and blood metabolism, immunity and antioxidant capacity, 1% to 2% hemp oil supplements was recommended for teddy dog diet.

Impact of coenzyme Q10 on inflammatory biomarkers and its role in future therapeutic strategies

Coenzyme Q (CoQ) is an important component of the mitochondrial electron transport chain. The finding that multiple chronic diseases show lower levels of CoQ10 has led to the possibility that CoQ10 supplementation could be an effective approach to ameliorate or prevent disease progression. In this review, we discuss the state of the art regarding the role of CoQ10 in health and disease and describe the latest clinical studies which have tested the effects of CoQ10 supplementation in inflammatory diseases. The results of these studies indicate that individuals suffering from inflammation-related diseases show improvement under the CoQ10 supplementation protocol. However, these results have been inconsistent, leading to the need for additional studies at the preclinical and clinical levels, involving a greater number of subjects and different treatment regimes.

Oxidative stress and obesity-related asthma

Obesity is an asthma comorbidity associated with poor control, increased exacerbation risk and reduced response to inhaled and systemic corticosteroids. It affects children and adults differentially. In those with early onset asthma, it associated with increased eosinophilic inflammation, whereas in late onset, it correlates with lower nitric oxide (NO) and predominantly non-T2 inflammation. There are probably multiple pathways by which obesity impacts asthma; airway and systemic oxidative stress has been proposed as a mechanism that could potentially explain the obesity mediated increased comorbidity and poor response to treatment. More likely than not, oxidative stress is an epiphenomenon of a very diverse set of processes driven by complex changes in airway and systemic metabolism. This article provides a comprehensive overview of the clinical, metabolic, pathophysiological and therapeutic aspects of oxidative stress in patients with obesity and asthma.

Effect of exposure to phthalates on association of polycyclic aromatic hydrocarbons with 8-hydroxy-2'-deoxyguanosine

BACKGROUND

Although polycyclic aromatic hydrocarbons (PAHs) and phthalates separately related to oxidative DNA damage have been reported, the joint effect of them on oxidative DNA damage need to be evaluated.

METHODS

In this pilot study, 106 participants were recruited from the community-dwelling residents (n=1240) of Wuhan city, China. Each individual provided three continuous days of spot urine samples for measuring the urinary monohydroxylated PAHs (OH-PAHs), phthalates metabolites and 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels in the two seasons. Linear mixed effect model and Bayesian Kernel Machine Regression (BKMR) were used to analyze joint effect of urinary PAHs and phthalates metabolites on urinary 8-OHdG levels. We measured cellular and mitochondrial reactive oxygen species (ROS), malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) levels as well as IL-6 and IL-8 secretions by the corresponding commercial kits in HepG2 cells treated with di (2-ethylhexyl) phthalate (DEHP, 62.5, 125.00, 250.00, 500.00 or 1000.00μM) alone, benzo[a]pyrene (BaP, 50.00μM) alone or both DEHP and BaP.

RESULTS

Linear mixed effect model showed that each of urinary PAHs metabolite was positively associated with urinary 8-OHdG levels; urinary level of mono (2-ethylhexyl) phthalate or monoisononyl phthalate was positively associated with urinary 8-OHdG levels; BKMR model indicated that a positive association of eight OH-PAHs with urinary 8-OHdG levels, nine urinary phthalates metabolites enhanced the association. We found that DEHP at the indicated concentration plus 50.00μM BaP increased cellular and mitochondrial ROS levels, IL-6 and IL-8 secretions at 24 and 48h as well as MDA levels and GSH-Px activities at 48h, compared to the solvent control.

CONCLUSIONS

Exposure to certain dose phthalates may attenuate the positive association of PAHs exposure with oxidative DNA damage in the body. DEHP at the certain concentrations enhanced BaP-induced mitochondrial ROS, pro-inflammatory response and the activation of the antioxidant defense system in HepG2 cells.

CoQ10 ameliorates monosodium glutamate-induced alteration in detrusor activity and responsiveness in rats via anti-inflammatory, anti-oxidant and channel inhibiting mechanisms

Background

Competent detrusor muscles with coordinated contraction and relaxation are crucial for normal urinary bladder storage and emptying functions. Hence, detrusor instability, and subsequently bladder overactivity, may lead to undesirable outcomes including incontinence. Multiple mechanisms may underlie the pathogenesis of detrusor overactivity including inflammation and oxidative stress. Herein, we tested the possibility that CoQ10 may have a potential therapeutic role in detrusor overactivity.

Methods

Forty adult male Wistar albino rats weighing 100-150 g were used in the present study. Rats were divided (10/group) into control (receiving vehicles), monosodium glutamate (MSG)-treated (receiving 5 mg/kg MSG daily for 15 consecutive days), MSG + OO-treated (receiving concomitantly 5 mg/kg MSG and olive oil for 15 consecutive days), MSG + CoQ10-treated (receiving concomitantly 5 mg/kg MSG and 100 mg/kg CoQ10 daily for 15 consecutive days) groups.

Results

MSG resulted in significant increase in bladder weight and sensitised the bladder smooth muscles to acetylcholine. MSG has also resulted in significant increase in bladder TNF-α, IL-6, malondialdehyde, nerve growth factor and connexion 43, with significant decrease in the antioxidant enzymes superoxide dismutase and catalase. Olive oil had no effect on MSG induced alterations of different parameters. Treatment with CoQ10 has resulted in a significant restoration of all the altered parameters.

Conclusion

Taken together, our results suggest that CoQ10 antagonizes the deleterious effects of MSG on detrusor activity. We propose that CoQ10 could be a therapeutic strategy targeting urinary bladder dysfunction.

Myalgic encephalomyelitis/chronic fatigue syndrome: From pathophysiological insights to novel therapeutic opportunities

Myalgic encephalomyelitis (ME) or chronic fatigue syndrome (CFS) is a common and disabling condition with a paucity of effective and evidence-based therapies, reflecting a major unmet need. Cognitive behavioural therapy and graded exercise are of modest benefit for only some ME/CFS patients, and many sufferers report aggravation of symptoms of fatigue with exercise. The presence of a multiplicity of pathophysiological abnormalities in at least the subgroup of people with ME/CFS diagnosed with the current international consensus "Fukuda" criteria, points to numerous potential therapeutic targets. Such abnormalities include extensive data showing that at least a subgroup has a pro-inflammatory state, increased oxidative and nitrosative stress, disruption of gut mucosal barriers and mitochondrial dysfunction together with dysregulated bioenergetics. In this paper, these pathways are summarised, and data regarding promising therapeutic options that target these pathways are highlighted; they include coenzyme Q₁₀, melatonin, curcumin, molecular hydrogen and N-acetylcysteine. These data are promising yet preliminary, suggesting hopeful avenues to address this major unmet burden of illness.

Antihypertensive Potential of Coenzyme Q10 via Free Radical Scavenging and Enhanced Akt-nNOS Signaling in the Nucleus Tractus Solitarii in Rats

SCOPE

In the Natural Medicines database, coenzyme Q10 (CoQ10) is classified as possibly effective for the treatment of hypertension. Patients with hypertension frequently have a significant deficiency of the antioxidant CoQ10. Furthermore, reactive oxygen species are overproduced in the nucleus tractus solitarii (NTS) during the cardiovascular regulation of hypertension in vivo. However, the molecular mechanisms by which CoQ10 modulates cardiovascular functions in the NTS are unclear. In this study, the effects of CoQ10 on superoxide generation, downstream NO signaling in the NTS, and blood pressure were evaluated in rats with fructose-induced hypertension.

METHODS AND RESULTS

Treatment with oral CoQ10 for 4 weeks abolished nicotinamide adenine dinucleotide phosphate-oxidase (NADPH oxidase) activation, decreased p38 phosphorylation, and increased superoxide dismutase 2 production in the NTS of fructose-fed rats. The serum levels of uric acid decrease in response to CoQ10 treatment in fructose-fed rats. Oral CoQ10 reduced blood pressure by inducing Akt and nNOS phosphorylation in NTS of fructose-induced hypertensive rats.

CONCLUSION

Oral CoQ10 decreases blood pressure by negatively regulating fructose-induced NADPH oxidase levels, abolishing ROS generation, reducing p38 phosphorylation, and enhancing the Akt-nNOS pathway in the NTS. These results support the beneficial effects of CoQ10 in oxidative stressassociated hypertension.

Coenzyme Q10 supplementation in acute ischemic stroke: Is it beneficial in short-term administration?

Backgrounds and aims: Clinical studies demonstrated that the efficacy of Coenzyme Q10 (CoQ10) as an adjuvant therapeutic agent in several neurological diseases such as Parkinson disease (PD), Huntington disease (HD), and migraine. The purpose of this study is to investigate oxidative stress effects, antioxidant enzymes activity, neuroinflammatory markers levels, and neurological outcome in acute ischemic stroke (AIS) patients following administration of CoQ10 (300 mg/day). Methods: Patients with AIS (n = 60) were randomly assigned to a placebo group (wheat starch, n = 30) or CoQ10-supplemented group (300 mg/day, n = 30). The intervention was administered for 4 weeks. Serum CoQ10 concentration, malondialdehyde (MDA), superoxide dismutase (SOD) activity, glial fibrillary acidic protein (GFAP) levels as primary outcomes and National Institute of Health Stroke Scale (NIHSS), Modified Ranking Scale (MRS), and Mini-Mental State Examination (MMSE) as secondary outcome were measured at the both beginning and end of the study. Results: Forty-four subjects with AIS completed the intervention study. A significant increase in CoQ10 level was observed in the supplement-treated group compared with placebo group (mean difference = 26.05 ± 26.63 ng/ml, 14.12 ± 14.69 ng/ml, respectively; P = 0.01), moreover CoQ10 supplementation improved NIHSS and MMSE scores significantly (P = 0.05, P = 0.03 respectively). but there were no statistically significant differences in MRS score, MDA, SOD, and GFAP levels between the two groups. Conclusions: CoQ10 probably due to low dose and short duration of supplementation, no favorable effects on MDA level, SOD activity and GFAP level.

Effect of Coenzyme Q10 Supplementation on Serum of High Sensitivity c-reactive Protein Level in Patients with Cardiovascular Diseases: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Possible effects of coenzyme Q10 (CoQ10) supplement on the serum level of high-sensitivity C-reactive protein (hs-CRP) in cardiovascular diseases (CVDs) remains unclear.

Objective

Therefore, this meta-analysis was conducted to investigate its effects on the serum hs-CRP level in patients with CVDs. A comprehensive search was conducted on the EMBASE, MEDLINE, and PubMed Central databases for pertinent papers in English up to November 2016. All randomized controlled trials (RCTs) that studied the effects of supplementation with CoQ10 on the serum of hs-CRP level in cardiovascular patients were included. We used random-effects models (the DerSimonian-Laird method) to estimate the pooled effect of selected studies and the I² test to assess the between-study heterogeneity. The subgroup analyses were carried out according to the baseline serum hs-CRP, quality assessment score, supplementation dosage, and duration of intervention. Of 205 studies, five trials were eligible for inclusion in this study with 159 participants in the ntervention and 143 participants in the placebo group. Results of the pooled analysis revealed that the CoQ10 supplementation had no significant effect on the serum level of hs-CRP compared with the placebo group (MD: 0.120; 95% = -0.944, 1.185; P = 0.825). Moreover, the subgroup analyses showed the baseline serum hs-CRP, quality assessment score, and duration of intervention can be sources of heterogeneity. The results of this study demonstrated that the beneficial effect of CoQ10 supplementation for patients with CVDs is observed in those who received this supplement for more than 12 weeks and with the baseline serum hs-CRP >3 mg/L.

Effect of Ubiquinol Intake on Defecation Frequency and Stool Form: A Prospective, Double-Blinded, Randomized Control Study

Bowel habits affect the quality of life (QOL) of patients with functional gastrointestinal disorders. This study evaluated the effects of reduced form coenzyme Q 10 (ubiquinol) intake on defecation frequency and stool form in patients with daily abdominal symptoms. This was a single-center, prospective, double-blind, randomized control study. Forty-one patients who had the daily symptom of constipation or diarrhea were randomly assigned at a 1:1 ratio to receive either ubiquinol (150 mg/day) or placebo for 12 weeks. Patients completed a daily diary to collect information regarding their numbers of defecations and stool forms according to the Bristol Stool Form (BSF) Scale for 7 days at baseline and 12 weeks. QOL was assessed using the 36-item short-form (SF-36) at baseline and 12 weeks. Twenty-one patients were assigned to the ubiquinol group, and 20 were assigned to the placebo group. At 12 weeks, the mean defecation frequency, compared to baseline, significantly decreased in the ubiquinol group (-0.1 times/day, P = .034) and increased in the placebo group (+0.3 times/day, P = .004). There was no significant change in the 12-week BSF Scale score of the ubiquinol group (+0.2, P = .123), whereas that of the placebo group was increased (+0.5, P < .001). The 12-week general health perception SF-36 score was significantly increased in the ubiquinol group (+3.5, P = .045), whereas there was no significant difference in that score in the placebo group (+1.2, P = .178). In conclusion, taking ubiquinol for 12 weeks decreased defecation frequencies and increased the QOL score, suggesting that ubiquinol may change the bowel habits and improve QOL in patients with abdominal distress.

Role of N-Acetylcysteine and Coenzyme Q10 in the Amelioration of Myocardial Energy Expenditure and Oxidative Stress, Induced by Carbon Tetrachloride Intoxication in Rats

This study is designed to evaluate the potential impact of N-acetyl cysteine (NAC) and coenzyme Q10 (CoQ10) each alone or in combination against carbon tetrachloride (CCl4)-induced cardiac damage in rats. Animals were treated with CCl4 in single intraperitoneal dose of 1 mL/Kg body weight; CCl4-intoxicated animals were pretreated with 20 mg/kg/d NAC or pretreated with 200 mg/kg/d CoQ10 or NAC and CoQ10 with the same previously mentioned doses. Carbon tetrachloride-intoxicated rats showed a significant elevation in nitric oxide and lipid peroxides and downregulation in reduced glutathione level and calcium adenosine triphosphatase. Cardiac glycolytic enzymes levels such as lactate dehydrogenase, phosphofructokinase, and hexokinase were declined coupled with a reduction in glucose content after CCl4 treatment. Moreover, myocardial hydroxyproline level was significantly increased after CCl4-treatment indicating accumulation of interstitial collagen. N-acetyl cysteine and/or CoQ10 effectively alleviated the disturbances in myocardial oxidative stress and antioxidant markers. These antioxidants effectively upregulated the reduction in cardiac energetic biomarkers due to CCl4 treatment. N-acetyl cysteine and/or CoQ10 significantly decreased hydroxyproline level compared to that of CCl4-treated rats. The current data showed that the aforementioned antioxidants have a remarkable cardioprotective effect, suggesting that they may be useful as prophylactic agents against the detrimental effects of cardiotoxins.

Salusin-β Is Involved in Diabetes Mellitus-Induced Endothelial Dysfunction via Degradation of Peroxisome Proliferator-Activated Receptor Gamma

The pathophysiological mechanisms for vascular lesions in diabetes mellitus (DM) are complex, among which endothelial dysfunction plays a vital role. Therapeutic target against endothelial injury may provide critical venues for treatment of diabetic vascular diseases. We recently identified that salusin-β contributed to high glucose-induced endothelial cell apoptosis. However, the roles of salusin-β in DM-induced endothelial dysfunction remain largely elusive. Male C57BL/6J mice were used to induce type 2 diabetes mellitus (T2DM) model. Human umbilical vein endothelial cells (HUVECs) were cultured in high glucose/high fat (HG/HF) medium. We demonstrated increased expression of salusin-β in diabetic aortic tissues and high-glucose/high-fat- (HG/HF-) incubated HUVECs. Disruption of salusin-β by shRNA abrogated the reactive oxygen species (ROS) production, inflammation, and nitrotyrosine content of HUVECs cultured in HG/HF medium. The HG/HF-mediated decrease in peroxisome proliferator-activated receptor γ (PPARγ) expression was restored by salusin-β shRNA, and PPARγ inhibitor T0070907 abolished the protective actions of salusin-β shRNA on endothelial injury in HG/HF-treated HUVECs. Salusin-β silencing obviously improved endothelium-dependent vasorelaxation, oxidative stress, inflammatory response, and nitrative stress in diabetic aorta. Taken together, our results highlighted the essential role of salusin-β in pathological endothelial dysfunction, and salusin-β may be a promising target in treatment of vascular complications of DM.

Investigation of 8-OHdG, CYP1A, HSP70 and transcriptional analyses of antioxidant defence system in liver tissues of rainbow trout exposed to eprinomectin

Eprinomectin (EPM), a member of avermectin family, is a semi-synthetic antibiotic. It has been known that avermectin family enters the aquatic environments and adversely affects the aquatic organisms. Effects of EPM is fully unknown in aquatic organisms especially fish, thus the aim of the present study was to investigate transcriptional changes (sod, cat, gpx) and activities of some antioxidant enzymes (superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) and malondialdehyde (MDA) levels, oxidative DNA damage (8-hydroxy-2-deoxyguanosine (8-OHdG)) and transcriptional changes of heat shock protein 70 (HSP70), and cytochromes P4501A (CYP1A) in liver tissues of rainbow trout exposed to sublethal EPM concentration (0.001 μg/L, 0.002 μg/L, 0.01 μg/L, 0.05 μg/L) for 24 h, 48 h, 72 h and 96 h. The decrease in antioxidant enzyme (SOD, CAT and GPx) activity, transcriptional changes (sod, cat, gpx, HSP70 and CYP1A genes) and increase in MDA level and activity of 8-OHdG in a dose-time-dependent manner in the liver of rainbow trout were observed. The down-regulated of antioxidant (sod, cat and gpx), HSP70 and CYP1A obviously, the severity of which increased with the concentration of EPM and exposure time. The results imply that EPM could induce oxidative damage to the liver tissue of rainbow trout. The information presented in this study is helpful to understand the mechanism of veterinary pharmaceuticals-induced oxidative stress in fishes.

Modulatory role of Co-enzyme Q10 on methionine and choline deficient diet-induced non-alcoholic steatohepatitis (NASH) in albino rats

The present study aimed to evaluate the hepato-protective and neuro-protective activity of Co-enzyme Q10 (CoQ10) on non-alcoholic steatohepatitis (NASH) in albino rats induced by methionine and choline-deficient (MCD) diet. Rats were fed an MCD diet for 8 weeks to induce non-alcoholic steatohepatitis. CoQ10 (10 mg/(kg·day)−1) was orally administered for 2 consecutive weeks. Twenty-four hours after the last dose of the drug, the behavioral test, namely the activity cage test, was performed and the activity counts were recorded. Serum alanine transaminase, aspartate aminotransferase, alkaline phosphatase, gamma-glutamyl transferase, total/direct bilirubin, and albumin were valued to assess liver function. Moreover, hepatic cytokines interleukin-6 as well as its modulator nuclear factor kappa-light-chain-enhancer of activated B cells were determined. In addition, brain biomarkers, viz ammonia, nitric oxide, and brain-derived neurotrophic factor (BDNF), were measured as they are reliable indices to assess brain damage. Histopathological and immunohistochemical examination of brain proliferating cell nuclear antigen in brain and liver tissues were also evaluated. Results revealed that MCD-induced NASH showed impairment in the liver functions with an increase in the liver inflammatory markers. Moreover, NASH resulted in pronounced brain dysfunction as evidenced by hyper-locomotor activity, a decrease in the BDNF level, as well as an increase in the brain nitric oxide and ammonia contents. Oral treatment of MCD-diet−fed rats with CoQ10 for 14 days showed a marked improvement in all the assigned parameters. Finally, it can be concluded that CoQ10 has a hepatoprotective and neuroprotective role in MCD-diet−induced NASH in rats.

Effects of coenzyme Q10 supplementation on inflammatory markers: A systematic review and meta-analysis of randomized controlled trials

The aims of this meta-analysis were to evaluate the effects of coenzyme Q10 (CoQ10) supplementation on inflammatory mediators including C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) by analyzing published randomized controlled trials (RCTs). A systematic search in PubMed, Cochrane Library and Clinicaltrials.gov was performed to identify eligible RCTs. Data synthesis was performed using a random- or a fixed-effects model depending on the results of heterogeneity tests, and pooled data were displayed as weighed mean difference (WMD) and 95% confidence interval (CI). Seventeen RCTs were selected for the meta-analysis. CoQ10 supplementation significantly reduced the levels of circulating CRP (WMD: -0.35mg/L, 95% CI: -0.64 to -0.05, P=0.022), IL-6 (WMD: -1.61pg/mL, 95% CI: -2.64 to -0.58, P=0.002) and TNF-α (WMD: -0.49pg/mL, 95% CI: -0.93 to -0.06, P=0.027). The results of meta-regression showed that the changes of CRP were independent of baseline CRP, treatment duration, dosage, and patients characteristics. In the meta-regression analyses, a higher baseline IL-6 level was significantly associated with greater effects of CoQ10 on IL-6 levels (P for interaction=0.006). In conclusion, this meta-analysis of RCTs suggests significant lowering effects of CoQ10 on CRP, IL-6 and TNF-α. However, results should be interpreted with caution because of the evidence of heterogeneity and limited number of studies.

Effects of Coenzyme Q10 on Markers of Inflammation: A Systematic Review and Meta-Analysis

Background/Objective

Chronic inflammation contributes to the onset and development of metabolic diseases. Clinical evidence has suggested that coenzyme Q10 (CoQ10) has some effects on inflammatory markers. However, these results are equivocal. The aim of this systematic review was to assess the effects of CoQ10 on serum levels of inflammatory markers in people with metabolic diseases.

Methods

Electronic databases were searched up to February 2016 for randomized controlled trials (RCTs). The outcome parameters were related to inflammatory factors, including interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) and C reactive protein (CRP). RevMan software was used for meta-analysis. Meta-regression analysis, Egger line regression test and Begg rank correlation test were performed by STATA software.

Results

Nine trials involving 428 subjects were included in this meta-analysis. The results showed that compared with control group, CoQ10 supplementation has significantly improved the serum level of CoQ10 by 1.17μg/ml [MD = 1.17, 95% CI (0.47 to 1.87) μg/ml, I² = 94%]. Meanwhile, it has significantly decreased TNF-α by 0.45 pg/ml [MD = -0.45, 95% CI (-0.67 to -0.24) pg/ml, I² = 0%]. No significant difference was observed between CoQ10 and placebo with regard to CRP [MD = -0.21, 95% CI (-0.60 to 0.17) mg/L, I² = 21%] and IL-6 [MD = -0.89, 95% CI (-1.95 to 0.16) pg/ml, I² = 84%].

Conclusions

CoQ10 supplementation may partly improve the process of inflammatory state. The effects of CoQ10 on inflammation should be further investigated by conducting larger sample size and well-defined trials of long enough duration.

Oxidative stress and metabolic disorders: Pathogenesis and therapeutic strategies

Increased body weight and metabolic disorder including insulin resistance, type 2 diabetes and cardiovascular complications together constitute metabolic syndrome. The pathogenesis of metabolic syndrome involves multitude of factors. A number of studies however indicate, with some conformity, that oxidative stress along with chronic inflammatory condition pave the way for the development of metabolic diseases. Oxidative stress, a state of lost balance between the oxidative and anti-oxidative systems of the cells and tissues, results in the over production of oxidative free radicals and reactive oxygen species (ROS). Excessive ROS generated could attack the cellular proteins, lipids and nucleic acids leading to cellular dysfunction including loss of energy metabolism, altered cell signalling and cell cycle control, genetic mutations, altered cellular transport mechanisms and overall decreased biological activity, immune activation and inflammation. In addition, nutritional stress such as that caused by high fat high carbohydrate diet also promotes oxidative stress as evident by increased lipid peroxidation products, protein carbonylation, and decreased antioxidant system and reduced glutathione (GSH) levels. These changes lead to initiation of pathogenic milieu and development of several chronic diseases. Studies suggest that in obese person oxidative stress and chronic inflammation are the important underlying factors that lead to development of pathologies such as carcinogenesis, obesity, diabetes, and cardiovascular diseases through altered cellular and nuclear mechanisms, including impaired DNA damage repair and cell cycle regulation. Here we discuss the aspects of metabolic disorders-induced oxidative stress in major pathological conditions and strategies for their prevention and therapy.

The Emerging Role of Disturbed CoQ Metabolism in Nonalcoholic Fatty Liver Disease Development and Progression

Although non-alcoholic fatty liver disease (NAFLD), characterised by the accumulation of triacylglycerol in the liver, is the most common liver disorder, the causes of its development and progression to the more serious non-alcoholic steatohepatitis (NASH) remain incompletely understood. Oxidative stress has been implicated as a key factor in both these processes, and mitochondrial dysfunction and inflammation are also believed to play a part. Coenzyme Q (CoQ) is a powerful antioxidant found in all cell membranes which has an essential role in mitochondrial respiration and also has anti-inflammatory properties. NAFLD has been shown to be associated with disturbances in plasma and liver CoQ concentrations, but the relationship between these changes and disease development and progression is not yet clear. Dietary supplementation with CoQ has been found to be hepatoprotective and to reduce oxidative stress and inflammation as well as improving mitochondrial dysfunction, suggesting that it may be beneficial in NAFLD. However, studies using animal models or patients with NAFLD have given inconclusive results. Overall, evidence is now emerging to indicate that disturbances in CoQ metabolism are involved in NAFLD development and progression to NASH, and this highlights the need for further studies with human subjects to fully clarify its role.

New animal models reveal that coenzyme Q2 (Coq2) and placenta-specific 8 (Plac8) are candidate genes for the onset of type 2 diabetes associated with obesity in rats

Obesity is a major risk factor for the onset of type 2 diabetes; however, little is known about the gene(s) involved. Therefore, we developed new animal models of obesity to search for diabetogenic genes associated with obesity. We generated double congenic rat strains with a hyperglycaemic quantitative trait locus (QTL) derived from the Otsuka Long-Evans Tokushima Fatty rat and a fa/fa (Lepr-/-) locus derived from the Zucker Fatty rat; phenotypic analysis for plasma glucose and insulin levels and RNA and protein levels were determined using reverse transcription quantitative PCR and Western blotting analyses, respectively. The double congenic strain F344-fa-nidd2 (Lepr-/- and Nidd2/of) exhibited significantly higher glucose levels and significantly lower hypoglycaemic response to insulin than the obese control strain F344-fa (Lepr-/-). These phenotypes were clearly observed in the obese strains but not in the lean strains. These results indicate that the Nidd2/of locus harbours a diabetogenic gene associated with obesity. We measured the expression of 60 genes in the Nidd2/of QTL region between the strains and found that the mRNA expression levels of five genes were significantly different between the strains under the condition of obesity. However, three of the five genes were differentially expressed in both obese and lean rats, indicating that these genes are not specific for the condition of obesity. Conversely, the other two genes, coenzyme Q2 (Coq2) and placenta-specific 8 (Plac8), were differentially expressed only in the obese rats, suggesting that these two genes are candidates for the onset of type 2 diabetes associated with obesity in rats.

Protective effects of nanoparticulate coenzyme Q10 and curcumin on inflammatory markers and lipid metabolism in streptozotocin-induced diabetic rats: a possible remedy to diabetic complications

Diabetes and its complications have been linked to increased levels of free radicals and systemic pro-inflammatory cytokines and to an altered lipid profile. Coenzyme Q10 and curcumin are potent antioxidants and anti-inflammatory agents but are underutilized clinically because of their poor bioavailability when administered orally. We have recently developed poly(D,L-lactic-co-glycolic acid)-based nanoparticles in which we have encapsulated coenzyme Q10 and curcumin to increase the oral bioavailability and therapeutic efficacy of the antioxidant molecules. These formulations when tested in streptozotocin-induced diabetic rats demonstrated protective effects on inflammatory markers as well as lipid metabolism. Coenzyme Q10 nanoparticulates reduced only C-reactive protein levels, whereas curcumin nanoparticles reduced levels of C-reactive protein, interleukin-6 and tumor necrosis factor-α. Administration of both nanoparticulates resulted in significant reductions of plasma triglycerides and total cholesterol and an increase in high-density lipoprotein cholesterol. Together, these data indicate the promise of coenzyme Q10 and curcumin in diabetes when delivered through nanoparticulate formulations.

Attenuating effects of coenzyme Q10 and amlodipine in ulcerative colitis model in rats

CONTEXT

Ulcerative colitis is a chronic inflammatory bowel disease. Recent studies reported a pivotal role of elevated intracellular calcium in this disorder. Coenzyme Q10 (CoQ10) and amlodipine are known to maintain cellular energy, decrease intracellular calcium concentration in addition to their antioxidant and anti-inflammatory properties.

OBJECTIVE

The aim of this study was to evaluate the possible protective effects of CoQ10, amlodipine and their combination on ulcerative colitis.

MATERIALS AND METHODS

Colitis was induced in rats by intracolonic injection of 3% acetic acid. CoQ10 (10 mg/kg), amlodipine (3 mg/kg) and their combination were administered for 8 consecutive days before induction of colitis.

RESULTS

Our results showed that administration of CoQ10, amlodipine and their combination decreased colon tissue malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), prostaglandin E2 (PGE2), myeloperoxidase (MPO) and heat shock protein (HSP70) levels induced by intracolonic injection of acetic acid and restored many of the colon structure in histological examination. On the other hand, they increased superoxide dismutase (SOD) activity, adenosine-5'-triphosphate (ATP) and interleukin-10 (IL-10) colonic contents.

DISCUSSION AND CONCLUSION

Administration of either CoQ10 or amlodipine was found to protect against acetic acid-induced colitis. Moreover, their combination was more effective than individual administration of either of them. The protective effect of CoQ10 and amlodipine may be in part via their antioxidant, anti-inflammatory and energy restoration properties.

Impact of gestational bisphenol A on oxidative stress and free fatty acids: Human association and interspecies animal testing studies

Bisphenol A (BPA) is a high production volume chemical and an endocrine disruptor. Developmental exposures to BPA have been linked to adult metabolic pathologies, but the pathways through which these disruptions occur remain unknown. This is a comprehensive interspecies association vs causal study to evaluate risks posed by prenatal BPA exposure and to facilitate discovery of biomarkers of relevance to BPA toxicity. Samples from human pregnancies during the first trimester and at term, as well as fetal and/or adult samples from prenatally BPA-treated sheep, rats, and mice, were collected to assess the impact of BPA on free fatty acid and oxidative stress dynamics. Mothers exposed to higher BPA during early to midpregnancy and their matching term cord samples displayed increased 3-nitrotyrosine (NY), a marker of nitrosative stress. Maternal samples had increased palmitic acid, which was positively correlated with NY. Sheep fetuses and adult sheep and rats prenatally exposed to a human-relevant exposure dose of BPA showed increased systemic nitrosative stress. The strongest effect of BPA on circulating free fatty acids was observed in adult mice in the absence of increased oxidative stress. This is the first multispecies study that combines human association and animal causal studies assessing the risk posed by prenatal BPA exposure to metabolic health. This study provides evidence of the induction of nitrosative stress by prenatal BPA in both the mother and fetus at time of birth and is thus supportive of the use of maternal NY as a biomarker for offspring health.

Coenzyme Q10 benefits symptoms in Gulf War veterans: results of a randomized double-blind study

We sought to assess whether coenzyme Q10 (CoQ10) benefits the chronic multisymptom problems that affect one-quarter to one-third of 1990-1 Gulf War veterans, using a randomized, double-blind, placebo-controlled study. Participants were 46 veterans meeting Kansas and Centers for Disease Control criteria for Gulf War illness. Intervention was PharmaNord (Denmark) CoQ10 100 mg per day (Q100), 300 mg per day (Q300), or an identical-appearing placebo for 3.5 ± 0.5 months. General self-rated health (GSRH), the primary outcome, differed across randomization arms at baseline, and sex significantly predicted GSRH change, compelling adjustment for baseline GSRH and prompting sex-stratified analysis. GSRH showed no significant benefit in the combined-sex sample. Among males (85% of participants), Q100 significantly benefited GSRH versus placebo and versus Q300, providing emphasis on Q100. Physical function (summary performance score, SPS) improved on Q100 versus placebo. A rise in CoQ10 approached significance as a predictor of improvement in GSRH and significantly predicted SPS improvement. Among 20 symptoms each present in half or more of the enrolled veterans, direction-of-difference on Q100 versus placebo was favorable for all except sleep problems; sign test 19:1, p=0.00004) with several symptoms individually significant. Significance for these symptoms despite the small sample underscores large effect sizes, and an apparent relation of key outcomes to CoQ10 change increases prospects for causality. In conclusion, Q100 conferred benefit to physical function and symptoms in veterans with Gulf War illness. Examination in a larger sample is warranted, and findings from this study can inform the conduct of a larger trial.

Effects of CoQ10 Supplementation on Lipid Profiles and Glycemic Control in Patients with Type 2 Diabetes: a randomized, double blind, placebo-controlled trial

Background

Low grade inflammation and oxidative stress are the key factors in the pathogenesis and development of diabetes and its complications. Coenzyme Q10 (CoQ10) is known as an antioxidant and has a vital role in generation of cellular energy providing. This study was undertaken to evaluate the effects of CoQ10 supplementation on lipid profiles and glycemic controls in patients with diabetes.

Methods

Fifty patients with diabetes were randomly allocated into two groups to receive either 150 mg CoQ10 or placebo daily for 12 weeks. Before and after supplementation, fasting venous blood samples were collected and lipid profiles containing triglyceride, total cholesterol, low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) and glycemic indices comprising of fasting plasma glucose (FPG), insulin and hemoglobin A₁C (HbA₁C) were measured. Insulin resistance was calculated using HOMA-IR index.

Results

Forty patients completed the study. After intervention FPG and HbA₁C were significantly lower in the CoQ10 group compared to the placebo group, but there were no significant differences in serum insulin and HOMA-IR between the two groups. Although total cholesterol did not change in the Q10 group after supplementation, triglyceride and HDL-C significantly decreased and LDL-C significantly increased in the CoQ10 group.

Conclusion

The present study showed that treatment with Q10 may improve glycemic control with no favorable effects on lipid profiles in type 2 patients with diabetes.

Trial registration

IRCT registry number: IRCT138806102394N1

Mitochondrial dysfunction in obesity: potential benefit and mechanism of Co-enzyme Q10 supplementation in metabolic syndrome

Co-enzyme Q10 (Co-Q10) is an essential component of the mitochondrial electron transport chain. Most cells are sensitive to co-enzyme Q10 (Co-Q10) deficiency. This deficiency has been implicated in several clinical disorders such as heart failure, hypertension, Parkinson's disease and obesity. The lipid lowering drug statin inhibits conversion of HMG-CoA to mevalonate and lowers plasma Co-Q10 concentrations. However, supplementation with Co-Q10 improves the pathophysiological condition of statin therapy. Recent evidence suggests that Co-Q10 supplementation may be useful for the treatment of obesity, oxidative stress and the inflammatory process in metabolic syndrome. The anti-inflammatory response and lipid metabolizing effect of Co-Q10 is probably mediated by transcriptional regulation of inflammation and lipid metabolism. This paper reviews the evidence showing beneficial role of Co-Q10 supplementation and its potential mechanism of action on contributing factors of metabolic and cardiovascular complications.

Novel CoQ10 antidiabetic mechanisms underlie its positive effect: modulation of insulin and adiponectine receptors, Tyrosine kinase, PI3K, glucose transporters, sRAGE and visfatin in insulin resistant/diabetic rats

As a nutritional supplement, coenzyme Q10 (CoQ10) was tested previously in several models of diabetes and/or insulin resistance (IR); however, its exact mechanisms have not been profoundly explicated. Hence, the objective of this work is to verify some of the possible mechanisms that underlie its therapeutic efficacy. Moreover, the study aimed to assess the potential modulatory effect of CoQ10 on the antidiabetic action of glimebiride. An insulin resistance/type 2 diabetic model was adopted, in which rats were fed high fat/high fructose diet (HFFD) for 6 weeks followed by a single sub-diabetogenic dose of streptozotocin (35 mg/kg, i.p.). At the end of the 7^th week animals were treated with CoQ10 (20 mg/kg, p.o) and/or glimebiride (0.5 mg/kg, p.o) for 2 weeks. CoQ10 alone opposed the HFFD effect and increased the hepatic/muscular content/activity of tyrosine kinase (TK), phosphatidylinositol kinase (PI3K), and adiponectin receptors. Conversely, it decreased the content/activity of insulin receptor isoforms, myeloperoxidase and glucose transporters (GLUT4; 2). Besides, it lowered significantly the serum levels of glucose, insulin, fructosamine and HOMA index, improved the serum lipid panel and elevated the levels of glutathione, sRAGE and adiponectin. On the other hand, CoQ10 lowered the serum levels of malondialdehyde, visfatin, ALT and AST. Surprisingly, CoQ10 effect surpassed that of glimepiride in almost all the assessed parameters, except for glucose, fructosamine, TK, PI3K, and GLUT4. Combining CoQ10 with glimepiride enhanced the effect of the latter on the aforementioned parameters. Conclusion: These results provided a new insight into the possible mechanisms by which CoQ10 improves insulin sensitivity and adjusts type 2 diabetic disorder. These mechanisms involve modulation of insulin and adiponectin receptors, as well as TK, PI3K, glucose transporters, besides improving lipid profile, redox system, sRAGE, and adipocytokines. The study also points to the potential positive effect of CoQ10 as an adds- on to conventional antidiabetic therapies.

Vascular endothelial function and oxidative stress are related to dietary niacin intake among healthy middle-aged and older adults

We tested the hypothesis that vascular endothelial function and oxidative stress are related to dietary niacin intake among healthy middle-aged and older adults. In 127 men and women aged 48-77 yr, brachial artery flow-mediated dilation (FMD) was positively related to dietary niacin intake [%change (Δ): r = 0.20, P < 0.05; mmΔ: r = 0.25, P < 0.01]. In subjects with above-average dietary niacin intake (≥ 22 mg/day, NHANES III), FMD was 25% greater than in subjects with below-average intake (P < 0.05). Stepwise linear regression revealed that dietary niacin intake (above vs. below average) was an independent predictor of FMD (%Δ: β = 1.8; mmΔ: β = 0.05, both P < 0.05). Plasma oxidized low-density lipoprotein, a marker of systemic oxidative stress, was inversely related to niacin intake (r = -0.23, P < 0.05) and was lower in subjects with above- vs. below-average niacin intake (48 ± 2 vs. 57 ± 2 mg/dl, P < 0.01). Intravenous infusion of the antioxidant vitamin C improved brachial FMD in subjects with below-average niacin intake (P < 0.001, n = 33), but not above-average (P > 0.05, n = 20). In endothelial cells sampled from the brachial artery of a subgroup, dietary niacin intake was inversely related to nitrotyrosine, a marker of peroxynitrite-mediated oxidative damage (r = -0.30, P < 0.05, n = 55), and expression of the prooxidant enzyme, NADPH oxidase (r = -0.44, P < 0.01, n = 37), and these markers were lower in subjects with above- vs. below-average niacin intake [nitrotyrosine: 0.39 ± 0.05 vs. 0.56 ± 0.07; NADPH oxidase: 0.38 ± 0.05 vs. 0.53 ± 0.05 (ratio to human umbilical vein endothelial cell control), both P < 0.05]. Our findings support the hypothesis that higher dietary niacin intake is associated with greater vascular endothelial function related to lower systemic and vascular oxidative stress among healthy middle-aged and older adults.

Coenzyme Q10 ameliorates pain and cartilage degradation in a rat model of osteoarthritis by regulating nitric oxide and inflammatory cytokines

Objective

To investigate the effect of CoenzymeQ10 (CoQ10) on pain severity and cartilage degeneration in an experimental model of rat osteoarthritis (OA).

Materials and Methods

OA was induced in rats by intra-articular injection of monosodium iodoacetate (MIA) to the knee. Oral administration of CoQ10 was initiated on day 4 after MIA injection. Pain severity was assessed by measuring secondary tactile allodynia using the von Frey assessment test. The degree of cartilage degradation was determined by measuring cartilage thickness and the amount of proteoglycan. The mankin scoring system was also used. Expressions of matrix metalloproteinase-13 (MMP-13), interleukin-1β (IL-1β), IL-6, IL-15, inducible nitric oxide synthase (iNOS), nitrotyrosine and receptor for advanced glycation end products (RAGE) were analyzed using immunohistochemistry.

Results

Treatment with CoQ10 demonstrated an antinociceptive effect in the OA animal model. The reduction in secondary tactile allodynia was shown by an increased pain withdrawal latency and pain withdrawal threshold. CoQ10 also attenuated cartilage degeneration in the osteoarthritic joints. MMP-13, IL-1β, IL-6, IL-15, iNOS, nitrotyrosine and RAGE expressions were upregulated in OA joints and significantly reduced with CoQ10 treatment.

Conclusion

CoQ10 exerts a therapeutic effect on OA via pain suppression and cartilage degeneration by inhibiting inflammatory mediators, which play a vital role in OA pathogenesis.

Coenzyme Q10 depletion in medical and neuropsychiatric disorders: potential repercussions and therapeutic implications

Coenzyme Q10 (CoQ10) is an antioxidant, a membrane stabilizer, and a vital cofactor in the mitochondrial electron transport chain, enabling the generation of adenosine triphosphate. It additionally regulates gene expression and apoptosis; is an essential cofactor of uncoupling proteins; and has anti-inflammatory, redox modulatory, and neuroprotective effects. This paper reviews the known physiological role of CoQ10 in cellular metabolism, cell death, differentiation and gene regulation, and examines the potential repercussions of CoQ10 depletion including its role in illnesses such as Parkinson's disease, depression, myalgic encephalomyelitis/chronic fatigue syndrome, and fibromyalgia. CoQ10 depletion may play a role in the pathophysiology of these disorders by modulating cellular processes including hydrogen peroxide formation, gene regulation, cytoprotection, bioenegetic performance, and regulation of cellular metabolism. CoQ10 treatment improves quality of life in patients with Parkinson's disease and may play a role in delaying the progression of that disorder. Administration of CoQ10 has antidepressive effects. CoQ10 treatment significantly reduces fatigue and improves ergonomic performance during exercise and thus may have potential in alleviating the exercise intolerance and exhaustion displayed by people with myalgic encepholamyletis/chronic fatigue syndrome. Administration of CoQ10 improves hyperalgesia and quality of life in patients with fibromyalgia. The evidence base for the effectiveness of treatment with CoQ10 may be explained via its ability to ameliorate oxidative stress and protect mitochondria.

Mitochondrial dysfunction in metabolic syndrome and asthma

Though severe or refractory asthma merely affects less than 10% of asthma population, it consumes significant health resources and contributes significant morbidity and mortality. Severe asthma does not fell in the routine definition of asthma and requires alternative treatment strategies. It has been observed that asthma severity increases with higher body mass index. The obese-asthmatics, in general, have the features of metabolic syndrome and are progressively causing a significant burden for both developed and developing countries thanks to the westernization of the world. As most of the features of metabolic syndrome seem to be originated from central obesity, the underlying mechanisms for metabolic syndrome could help us to understand the pathobiology of obese-asthma condition. While mitochondrial dysfunction is the common factor for most of the risk factors of metabolic syndrome, such as central obesity, dyslipidemia, hypertension, insulin resistance, and type 2 diabetes, the involvement of mitochondria in obese-asthma pathogenesis seems to be important as mitochondrial dysfunction has recently been shown to be involved in airway epithelial injury and asthma pathogenesis. This review discusses current understanding of the overlapping features between metabolic syndrome and asthma in relation to mitochondrial structural and functional alterations with an aim to uncover mechanisms for obese-asthma.

Anti-aging Effects of Co-enzyme Q10 on Periodontal Tissues

Oxidative stress is associated with age-related reactions. The anti-oxidative effects of a reduced form of co-enzyme Q10 (rCoQ10) suppress oxidative stress, which may contribute to the prevention of age-related inflammatory reactions. We examined the effects of topically applied rCoQ10 on periodontal inflammatory reactions in a rat aging model. Male Fischer 344 rats, 2 (n = 6) and 4 mos (n = 18) of age, were used. All of the two-month-old rats and 6 of the four-month-old rats were sacrificed and 12 remaining four-month-old rats received topically applied ointment with or without 1% rCoQ10 on the gingival surface until they reached 6 mos of age. The rats showed an age-dependent increase in circulating oxidative stress. RCoQ10 decreased oxidative DNA damage and tartrate-resistant acid-phosphatase-positive osteoclasts in the periodontal tissue at 6 mos of age as compared with the control. The same conditions lowered gene expression of caspase-1 and interleukin-1β in the periodontal tissue. Furthermore, Nod-like receptor protein 3 inflammasomes were less activated in periodontal tissues from rCoQ10-treated rats as compared with the control rats. Our results suggest that rCoQ10 suppresses age-related inflammatory reactions and osteoclast differentiation by inhibiting oxidative stress.

Prophylactic and Antinociceptive Effects of Coenzyme Q10 on Diabetic Neuropathic Pain in a Mouse Model of Type 1 Diabetes

Background:

Oxidative stress is a key factor implicated in the development of diabetic neuropathy. This study evaluates the prophylactic and antinociceptive effects of the antioxidant coenzyme Q10 (CoQ10) on diabetes-induced neuropathic pain in a diabetic mouse model.

Methods:

Total 56 mice with type 1 diabetes induced by streptozotocin were used, 20 normal mice were used as control. Mechanical and thermal nociceptive behavioral assays were applied to evaluate diabetic neuropathic pain. Tissue lipid peroxidation, immunohistochemistry, reverse transcription, and polymerase chain reaction were used to evaluate the molecular mechanisms of CoQ10. Data are presented as mean ± SEM.

Results:

CoQ10 administration was associated with reduced loss of body weight compared with nontreated diabetic mice, without affecting blood glucose levels. Low dose and long-term administration of CoQ10 prevented the development of neuropathic pain. Treatment with CoQ10 produced a significant dose-dependent inhibition of mechanical allodynia and thermal hyperalgesia in diabetic mice. Dorsal root ganglia, sciatic nerve, and spinal cord tissues from diabetic mice demonstrated increased lipid peroxidation that was reduced by CoQ10 treatment. CoQ10 administration was also noted to reduce the proinflammatory factors in the peripheral and central nervous system.

Conclusions:

The results of this study support the hypothesis that hyperglycemia induced neuronal oxidative damage and reactive inflammation may be pathogenic in diabetic neuropathic pain. CoQ10 may be protective by inhibiting oxidative stress and reducing inflammation by down-regulating proinflammatory factors. These results suggest that CoQ10 administration may represent a low-risk, high-reward strategy for preventing or treating diabetic neuropathy.

Is there a place for coenzyme Q in the management of metabolic disorders associated with obesity?

Coenzyme Q (CoQ), a lipophilic cofactor of the electron transport chain in the mitochondria, can be synthesized endogenously or provided by food. The aim of this review is to summarize the in vitro cell culture studies, the in vivo animal studies, and the human studies investigating the impact of CoQ supplementation on the occurrence of obesity and related disorders (diabetes, hypertension, lipemia, and atherosclerosis). The antioxidative properties of CoQ have been observed in different experimental models of atherosclerosis, obesity, and diabetes. The recent discovery of the anti-inflammatory effect of CoQ, mostly described in vitro, has generated increased interest in CoQ supplementation, but it needs to be confirmed in vivo in pathological situations. CoQ intervention studies in humans failed to show reproducible effects on body weight, fat mass, or glycemia, but CoQ supplementation does seem to have an antihypertensive effect. The molecular mechanism to explain this effect has only recently been discovered.

Maternal antioxidants prevent β-cell apoptosis and promote formation of dual hormone-expressing endocrine cells in male offspring following fetal and neonatal nicotine exposure

BACKGROUND

Fetal and neonatal nicotine exposure causes β-cell oxidative stress and apoptosis in neonates, leading to adult-onset dysglycemia. The aim of the present study was to determine whether an antioxidant intervention could prevent nicotine-induced β-cell loss.

METHODS

Nulliparous female Wistar rats received daily subcutaneous injections of either saline or nicotine bitartrate (1.0 mg/kg per day) for 2 weeks prior to mating until weaning. Nicotine-exposed dams received either normal chow or diet containing antioxidants (1000 IU/kg vitamin E, 0.25% w/w coenzyme Q10, and 0.1% w/w α-lipoic acid) during mating, pregnancy, and lactation; saline-exposed dams received normal chow. Pancreatic tissue was collected from male offspring at 3 weeks of age to measure β-cell fraction, apoptosis, proliferation, and the presence of cells coexpressing insulin and glucagon.

RESULTS

The birth weight of offspring born to nicotine-exposed dams was significantly reduced in those receiving dietary antioxidants compared with those fed normal chow. Most interestingly, the antioxidant intervention to nicotine-exposed dams prevented the β-cell loss and apoptosis observed in nicotine-exposed male offspring whose mothers did not receive antioxidants. Male pups born to nicotine-treated mothers receiving antioxidants also had a tendency for increased β-cell proliferation and a significant increase in islets containing insulin/glucagon bihormonal cells compared with the other two treatment groups.

CONCLUSION

The present study demonstrates that exposure to maternal antioxidants protects developing β-cells from the damaging effects of nicotine, thus preserving β-cell mass.

Oxidative stress correlates with headache symptoms in fibromyalgia: coenzyme Q₁₀ effect on clinical improvement

BACKGROUND

Fibromyalgia (FM) is a chronic pain syndrome with unknown etiology and a wide spectrum of symptoms such as allodynia, debilitating fatigue, joint stiffness and migraine. Recent studies have shown some evidences demonstrating that oxidative stress is associated to clinical symptoms in FM of fibromyalgia. We examined oxidative stress and bioenergetic status in blood mononuclear cells (BMCs) and its association to headache symptoms in FM patients. The effects of oral coenzyme Q(10) (CoQ(10)) supplementation on biochemical markers and clinical improvement were also evaluated.

METHODS

We studied 20 FM patients and 15 healthy controls. Clinical parameters were evaluated using the Fibromyalgia Impact Questionnaire (FIQ), visual analogues scales (VAS), and the Headache Impact Test (HIT-6). Oxidative stress was determined by measuring CoQ(10), catalase and lipid peroxidation (LPO) levels in BMCs. Bioenergetic status was assessed by measuring ATP levels in BMCs.

RESULTS

We found decreased CoQ(10), catalase and ATP levels in BMCs from FM patients as compared to normal control (P < 0.05 and P < 0.001, respectively) We also found increased level of LPO in BMCs from FM patients as compared to normal control (P < 0.001). Significant negative correlations between CoQ(10) or catalase levels in BMCs and headache parameters were observed (r  = -0.59, P < 0.05; r  =  -0.68, P < 0.05, respectively). Furthermore, LPO levels showed a significant positive correlation with HIT-6 (r = 0.33, P<0.05). Oral CoQ(10) supplementation restored biochemical parameters and induced a significant improvement in clinical and headache symptoms (P < 0.001).

DISCUSSION

The results of this study suggest a role for mitochondrial dysfunction and oxidative stress in the headache symptoms associated with FM. CoQ10 supplementation should be examined in a larger placebo controlled trial as a possible treatment in FM.