Clinical aspects of coenzyme Q10: an update

Ubiquinol Short-Term Supplementation Prior to Strenuous Exercise Improves Physical Performance and Diminishes Muscle Damage

The benefits of physical exercise on health are diminished when it is non-planned, strenuous, or vigorous, which causes an increase in oxygen consumption and production of free radicals, particularly serious at the muscular level. Ubiquinol could help achieve an antioxidant, anti-inflammatory, and ergogenic effect. The aim of this study is to evaluate whether a supplementation of ubiquinol during a short period could have a positive effect on muscle aggression, physical performance, and fatigue perception in non-elite athletes after high intensity circuit weight training. One hundred healthy and well-trained men, (firemen of the Fire Department of Granada) were enrolled in a placebo-controlled, double-blinded, and randomized study, and separated into two groups: the placebo group (PG, n = 50); and the ubiquinol group (UG, n = 50), supplemented with an oral dose. Before and after the intervention, data related to the number of repetitions, muscle strength, and perceived exertion, as well as blood samples were collected. An increase was observed in the UG regarding average load and repetitions, revealing an improvement in muscle performance. Ubiquinol supplementation also reduced muscle damage markers, showing a protective effect on muscle fibers. Therefore, this study provides evidence that ubiquinol supplementation improves muscle performance and prevents muscle damage after strenuous exercise in a population of well-trained individuals who are not elite athletes.

Impact of dyslipidemia in the development of cardiovascular complications: Delineating the potential therapeutic role of coenzyme Q10

Dyslipidemia is one of the major risk factors for the development of cardiovascular disease (CVD) in patients with type 2 diabetes (T2D). This metabolic anomality is implicated in the generation of oxidative stress, an inevitable process involved in destructive mechanisms leading to myocardial damage. Fortunately, commonly used drugs like statins can counteract the detrimental effects of dyslipidemia by lowering cholesterol to reduce CVD-risk in patients with T2D. Statins mainly function by blocking the production of cholesterol by targeting the mevalonate pathway. However, by blocking cholesterol synthesis, statins coincidently inhibit the synthesis of other essential isoprenoid intermediates of the mevalonate pathway like farnesyl pyrophosphate and coenzyme Q₁₀ (CoQ₁₀). The latter is by far the most important co-factor and co-enzyme required for efficient mitochondrial oxidative capacity, in addition to its robust antioxidant properties. In fact, supplementation with CoQ₁₀ has been found to be beneficial in ameliorating oxidative stress and improving blood flow in subjects with mild dyslipidemia.. Beyond discussing the destructive effects of oxidative stress in dyslipidemia-induced CVD-related complications, the current review brings a unique perspective in exploring the mevalonate pathway to block cholesterol synthesis while enhancing or maintaining CoQ₁₀ levels in conditions of dyslipidemia. Furthermore, this review disscusses the therapeutic potential of bioactive compounds in targeting the downstream of the mevalonate pathway, more importantly, their ability to block cholesterol while maintaining CoQ₁₀ biosynthesis to protect against the destructive complications of dyslipidemia.

Detrimental Effects of Lipid Peroxidation in Type 2 Diabetes: Exploring the Neutralizing Influence of Antioxidants

Lipid peroxidation, including its prominent byproducts such as malondialdehyde (MDA) and 4-hydroxy-2-nonenal (4-HNE), has long been linked with worsened metabolic health in patients with type 2 diabetes (T2D). In fact, patients with T2D already display increased levels of lipids in circulation, including low-density lipoprotein-cholesterol and triglycerides, which are easily attacked by reactive oxygen molecules to give rise to lipid peroxidation. This process severely depletes intracellular antioxidants to cause excess generation of oxidative stress. This consequence mainly drives poor glycemic control and metabolic complications that are implicated in the development of cardiovascular disease. The current review explores the pathological relevance of elevated lipid peroxidation products in T2D, especially highlighting their potential role as biomarkers and therapeutic targets in disease severity. In addition, we briefly explain the implication of some prominent antioxidant enzymes/factors involved in the blockade of lipid peroxidation, including termination reactions that involve the effect of antioxidants, such as catalase, coenzyme Q₁₀, glutathione peroxidase, and superoxide dismutase, as well as vitamins C and E.

Overexpression of enzymes in glycolysis and energy metabolic pathways to enhance coenzyme Q10 production in Rhodobacter sphaeroides VK-2-3

We subjected the components of the glycolysis and energy metabolism pathways of Rhodobacter sphaeroides (R. sphaeroides) to metabolic engineering to improve the titer and yield of coenzyme Q10 (CoQ10). Phosphofructokinase (PFK), cyclic adenylate-dependent protein kinase (PKAC), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and adenosine triphosphate hydrolase (KdpC) were overexpressed in R. sphaeroides VK-2-3 (VK-2-3). The strains were labeled R. sphaeroides PFK (RS.PFK), RS.PKAC, RS.PFK–PKAC, RS.KdpC, RS.GAPDH, and RS.KdpC–GAPDH. Results showed that the CoQ10 titers of RS.PFK, RS.PKAC, and RS.PFK–PKAC were 300.96 ± 0.87, 405.94 ± 4.77, and 379.94 ± 0.42 mg/l, respectively. The CoQ10 titers of RS.PFK and VK-2-3 were not significantly different; however, those for RS.PKAC and RS.PFK–PKAC were 13 and 6% higher than that of VK-2-3, respectively. Further, the titers of RS.KdpC, RS.GAPDH, and RS.KdpC–GAPDH were 360.17 ± 0.39, 409.79 ± 0.76, and 359.87 ± 1.14 mg/l, respectively. The titers of RS.KdpC and RS.KdpC–GAPDH were not significantly different from that for VK-2-3, whereas that for RS.GAPDH was 14% higher than that of VK-2-3. Finally, when the cultures of RS.GAPDH and VK-2-3 were scaled up in 5-L fermenters, the CoQ10 titers and RS.GAPDH yields increased by 44.3 and 37.8%, respectively, compared with VK-2-3.To the best of our knowledge, the glycolysis pathway of R. sphaeroides was studied for the first time in this study. We genetically modified the components of the energy metabolism pathway to obtain the strain with high yield of CoQ10 mutant RS.GAPDH. The findings of this study can serve as a basis for future studies involving metabolic engineering of CoQ10-producing strains.

Assessing Cellular Uptake of Exogenous Coenzyme Q10 into Human Skin Cells by X-ray Fluorescence Imaging

X-ray fluorescence (XRF) imaging is a highly sensitive non-invasive imaging method for detection of small element quantities in objects, from human-sized scales down to single-cell organelles, using various X-ray beam sizes. Our aim was to investigate the cellular uptake and distribution of Q₁₀, a highly conserved coenzyme with antioxidant and bioenergetic properties. Q₁₀ was labeled with iodine (I₂-Q₁₀) and individual primary human skin cells were scanned with nano-focused beams. Distribution of I₂-Q₁₀ molecules taken up inside the screened individual skin cells was measured, with a clear correlation between individual Q₁₀ uptake and cell size. Experiments revealed that labeling Q₁₀ with iodine causes no artificial side effects as a result of the labeling procedure itself, and thus is a perfect means of investigating bioavailability and distribution of Q₁₀ in cells. In summary, individual cellular Q₁₀ uptake was demonstrated by XRF, opening the path towards Q₁₀ multi-scale tracking for biodistribution studies.

Water-soluble coenzyme Q10 provides better protection than lipid-soluble coenzyme Q10 in a rat model of chronic tacrolimus nephropathy

BACKGROUND/AIMS

Coenzyme Q10 (CoQ10), is a promising antioxidant; however, low bioavailability owing to lipid-solubility is a limiting factor. We developed water-soluble CoQ10 (CoQ10-W) and compared its effects with conventional lipid-soluble CoQ10 (CoQ10-L) in an experimental model of chronic tacrolimus (Tac) nephropathy.

METHODS

CoQ10-W was developed from a glycyrrhizic-carnitine mixed layer CoQ10 micelle based on acyltransferases. Chronic nephropathy was induced in rats with 28-day Tac treatment; they were concomitantly treated with CoQ10-L or CoQ10-W. CoQ10 level in plasma and kidney were measured using liquid chromatography-mass spectrometry. CoQ10-W and CoQ10-L effects on Tac-induced nephropathy were assessed in terms of renal function, histopathology, oxidative stress, and apoptotic cell death. Their effects on cell viability and reactive oxygen species (ROS) production were assessed in cultured proximal tubular cells, human kidney 2 (HK-2) cells.

RESULTS

The plasma CoQ10 level was significantly higher in the CoQ10-W group than in the CoQ10-L group. Tac treatment caused renal dysfunction, typical pathologic lesions, and oxidative stress markers. Serum creatinine was restored in the Tac + CoQ10-L or CoQ10-W groups compared with that in the Tac group. CoQ10-W administration reduced oxidative stress and apoptosis markers. Mitochondrial ultrastructure assessment revealed that the addition of CoQ10-L or CoQ10-W with Tac increased mitochondrial size and number than Tac treatment alone. In vitro investigations revealed that both CoQ10-L and CoQ10-W improved cell viability and reduced ROS production in the Tac-induced HK-2 cell injury.

CONCLUSION

CoQ10-W has a better therapeutic effect in Tac-induced renal injury than conventional CoQ10-L, possibly associated with improved CoQ10 bioavailability.

Statins in Neuro-ophthalmology

Statins are effective and well-tolerated hypolipidaemic agents which have been increasingly studied for their pleiotropic immunomodulatory and anti-inflammatory effects. Statins have potential therapeutic benefit in a range of neuro-ophthalmological conditions but may also induce or exacerbate certain neurological disorders. This literature review examines evidence from clinical and in vitro studies assessing the effects of statins in myasthenia gravis, myopathy, multiple sclerosis, neuromyelitis optica, idiopathic intracranial hypertension (pseudotumour cerebri), migraine, giant cell arteritis, Bell's palsy, ocular ischaemia, stroke, Alzheimer's disease and Parkinson's disease.

Beneficial Effect of Ubiquinol on Hematological and Inflammatory Signaling during Exercise

Strenuous exercise (any activity that expends six metabolic equivalents per minute or more causing sensations of fatigue and exhaustion to occur, inducing deleterious effects, affecting negatively different cells), induces muscle damage and hematological changes associated with high production of pro-inflammatory mediators related to muscle damage and sports anemia. The objective of this study was to determine whether short-term oral ubiquinol supplementation can prevent accumulation of inflammatory mediators and hematological impairment associated to strenuous exercise. For this purpose, 100 healthy and well-trained firemen were classified in two groups: Ubiquinol (experimental group), and placebo group (control). The protocol was two identical strenuous exercise tests with rest period between tests of 24 h. Blood samples were collected before supplementation (basal value) (T1), after supplementation (T2), after first physical exercise test (T3), after 24 h of rest (T4), and after second physical exercise test (T5). Hematological parameters, pro- and anti-inflammatory cytokines and growth factors were measured. Red blood cells (RBC), hematocrit, hemoglobin, VEGF, NO, EGF, IL-1ra, and IL-10 increased in the ubiquinol group while IL-1, IL-8, and MCP-1 decreased. Ubiquinol supplementation during high intensity exercise could modulate inflammatory signaling, expression of pro-inflammatory, and increasing some anti-inflammatory cytokines. During exercise, RBC, hemoglobin, hematocrit, VEGF, and EGF increased in ubiquinol group, revealing a possible pro-angiogenic effect, improving oxygen supply and exerting a possible protective effect on other physiological alterations.

Effect of ubiquinol supplementation on biochemical and oxidative stress indexes after intense exercise in young athletes

Objectives: Physical exercise significantly impacts the biochemistry of the organism. Ubiquinone is a key component of the mitochondrial respiratory chain and ubiquinol, its reduced and active form, is an emerging molecule in sport nutrition. The aim of this study was to evaluate the effect of ubiquinol supplementation on biochemical and oxidative stress indexes after an intense bout of exercise.

Methods: 21 male young athletes (26 + 5 years of age) were randomized in two groups according to a double blind cross-over study, either supplemented with ubiquinol (200 mg/day) or placebo for 1 month. Blood was withdrawn before and after a single bout of intense exercise (40 min run at 85% maxHR). Physical performance, hematochemical parameters, ubiquinone/ubiquinol plasma content, intracellular reactive oxygen species (ROS) level, mitochondrial membrane depolarization, paraoxonase activity and oxidative DNA damage were analyzed.

Results: A single bout of intense exercise produced a significant increase in most hematochemical indexes, in particular CK and Mb while, on the contrary, normalized coenzyme Q₁₀ plasma content decreased significantly in all subjects. Ubiquinol supplementation prevented exercise-induced CoQ deprivation and decrease in paraoxonase activity. Moreover at a cellular level, in peripheral blood mononuclear cells, ubiquinol supplementation was associated with a significant decrease in cytosolic ROS while mitochondrial membrane potential and oxidative DNA damage remained unchanged.

Discussion: Data highlights a very rapid dynamic of CoQ depletion following intense exercise underlying an increased demand by the organism. Ubiquinol supplementation minimized exercise-induced depletion and enhanced plasma and cellular antioxidant levels but it was not able to improve physical performance indexes or markers of muscular damage.

Oxidative stress in adult growth hormone deficiency: different plasma antioxidant patterns in comparison with metabolic syndrome

BACKGROUND AND AIMS

Growth hormone deficiency (GHD) is a condition associated with increased cardiovascular risk and insulin-resistance. Oxidative stress (OS) could be a mechanism underlying both these phenomena. In order to investigate plasma antioxidant defenses in such condition, we evaluated adults with GHD, compared with controls and metabolic syndrome patients (MetS), studying plasma total antioxidant capacity (TAC) and coenzyme Q10 (CoQ10, lipophilic antioxidant) levels, both in its oxidized and reduced forms, correlating this data with metabolic and hormonal pattern.

MATERIALS AND METHODS

In this case-control study, 51 GHD, 36 controls, and 35 MetS were enrolled. An evaluation of hormonal and metabolic parameters was performed. TAC was measured using the system metmyoglobin -H₂0₂ and the chromogen ABTS, whose radical form is spectroscopically revealed; latency time (LAG) in the appearance of ABTS^● is proportional to antioxidant in sample. CoQ10 was assayed by electrochemical method.

RESULTS

Despite HOMA index was higher in both GHD and MetS (2.2 ± 0.3 and 3.1 ± 0.3 vs. 1.2 ± 0.2 in controls), only in MetS we observed lower LAG levels (64.5 ± 3.1 s vs. 82.8 ± 5.8 in GHD and 80.6 ± 6.6 in controls), suggesting an increased consumption of antioxidants. LAG significantly correlated with uric acid only in MetS (r ² = 0.65, p < 0.001), suggesting a different pattern of antioxidants. CoQ10 exhibited a trend toward lower levels in GHD, although not significant.

CONCLUSIONS

Our data indicate that GHD, although sharing with MetS various metabolic features, including increased HOMA levels, showed a different pattern of plasma antioxidants, suggesting inadequate reactivity toward radical production rather than an antioxidants consumption as in MetS.

Effects of Coenzyme Q10 Supplementation on Exercise Performance and Markers of Oxidative Stress in Hemodialysis Patients: A Double-Blind Placebo-Controlled Crossover Trial

Coenzyme Q10 (CoQ10) supplementation has been shown to decrease oxidative stress in a number of clinical settings. However, there are mixed results regarding the role of CoQ10 supplementation on exercise performance. Chronic kidney disease is recognized as an inflammatory state, and hemodialysis patients have low level of exercise performance. We aimed to evaluate the effect of CoQ10 supplementation on oxidative stress markers and exercise performance measures. This was a prospective, double-blind, placebo-controlled, crossover study in which all patients received placebo and oral CoQ10 200 mg/d. Participants underwent 6-minute walking test and cycle ergometer. Blood samples were drawn to determine malondialdehyde, oxidized low-density lipoprotein, superoxide dismutase, and glutathione peroxidase. Walking distance in 6-minute walking test and estimated maximal oxygen consumption (VO2max) were recorded. Twenty-eight patients were randomized, but 23 patients completed the study protocol. Serum CoQ10 level significantly increased with supplementation compared with basal values (P < 0.05). Neither walking distance nor estimated VO2max was different between the placebo and CoQ10 groups (P > 0.05). Serum malondialdehyde levels significantly increased in both groups compared with baseline values just after the exercise (P < 0.05). There was no difference in markers of oxidative stress and antioxidant system between placebo and CoQ10 supplementation with exercise (P > 0.05). The results of this study showed no significant effect of CoQ10 supplementation on exercise performance measures and oxidative system markers compared with placebo in maintenance hemodialysis patients.

Reversal of statin-induced memory dysfunction by co-enzyme Q10: a case report

Statins are useful in the armamentarium of the clinician dealing with dyslipidemia, which increases cardiovascular morbi-mortality in hypertensive and diabetic patients among others. Dyslipidemia commonly exists as a comorbidity factor in the development of atherosclerotic cardiovascular disease. Use of statins is however associated with side effects which at times are so disabling as to interfere with activities of daily living. There are various ways of dealing with this, including use of more water-soluble varieties, intermittent dosing, or use of statin alternatives. Of late, use of co-enzyme Q10 has become acceptable for the muscle side effects. Only one report of any benefit on the rarely reported memory side effect was encountered by the author in the search of English medical literature. This is a report of a documented case of a Nigerian woman with history of statin intolerance in this case, memory dysfunction despite persisting dyslipidemia comorbidity. Her memory dysfunction side effect which interfered with activities of daily living and background muscle pain cleared when coenzyme Q10 was administered alongside low dose statin. Her lipid profile normalized and has remained normal. It is being recommended for use when statin side effects (muscle- and memory-related) impair quality of life and leave patient at dyslipidemia-induced cardiovascular morbi-mortality.

Effects of coenzyme Q10 in conjunction with vitamin E on retinal-evoked and cortical-evoked responses in patients with open-angle glaucoma

PURPOSE

To evaluate pattern-evoked retinal and cortical responses [pattern electroretinogram (PERG) and visual-evoked potential (VEP), respectively] after treatment with coenzyme Q10 in conjunction with vitamin E in open-angle glaucoma (OAG) patients.

METHODS

Forty-three OAG patients (mean age, 52.5±5.29 y; intraocular pressure <18 mm Hg with β-blocker monoterapy only) were enrolled. At baseline and after 6 and 12 months, simultaneous recordings of PERG and VEPs were obtained from 22 OAG patients who underwent treatment consisting of coenzyme Q10 and vitamin E (Coqun, 2 drops/d) in addition to β-blocker monoterapy (GC group), and from 21 OAG patients who were only treated with β-blockers (GP group).

RESULTS

At baseline, intraocular pressure, PERG, and VEP parameters were similar in both GC and GP groups (analysis of variance, P>0.05). After 6 and 12 months, PERG and VEP response parameters of GP patients were unchanged when compared to baseline. In GC patients, PERG P50 and VEP P100 implicit times were decreased, whereas PERG P50-N95 and VEP N75-P100 amplitudes were increased (P<0.01) when compared to baseline. In the GC group, the differences in implicit times and amplitudes with respect to baseline were significantly larger (P<0.01) than those recorded in the GP group. The improvement (12 mo minus baseline) of VEP implicit time was significantly correlated with the changes of PERG P50-N95 amplitude (r=-0.66171, P=0.0008) and P50 implicit time (r=0.68364, P=0.00045) over a period of 12 months.

CONCLUSIONS

Coenzyme Q10 associated with vitamin E administration in OAG shows a beneficial effect on the inner retinal function (PERG improvement) with consequent enhancement of the visual cortical responses (VEP improvement).

Strategies for oral delivery and mitochondrial targeting of CoQ10

Coenzyme Q10 (CoQ10), also known as ubiquinone or ubidecarenone, is a powerful, endogenously produced, intracellularly existing lipophilic antioxidant. It combats reactive oxygen species (ROS) known to be responsible for a variety of human pathological conditions. Its target site is the inner mitochondrial membrane (IMM) of each cell. In case of deficiency and/or aging, CoQ10 oral supplementation is warranted. However, CoQ10 has low oral bioavailability due to its lipophilic nature, large molecular weight, regional differences in its gastrointestinal permeability and involvement of multitransporters. Intracellular delivery and mitochondrial target ability issues pose additional hurdles. To maximize CoQ10 delivery to its biopharmaceutical target, numerous approaches have been undertaken. The review summaries the current research on CoQ10 bioavailability and highlights the headways to obtain a satisfactory intracellular and targeted mitochondrial delivery. Unresolved questions and research gaps were identified to bring this promising natural product to the forefront of therapeutic agents for treatment of different pathologies.

Coenzyme Q10 promotes macrophage cholesterol efflux by regulation of the activator protein-1/miR-378/ATP-binding cassette transporter G1-signaling pathway

OBJECTIVE

Recent studies have shown the role of miRNAs in macrophage reverse cholesterol transport and atherogenesis. We hypothesized that coenzyme Q10 (CoQ10) may increase macrophage reverse cholesterol transport by regulating miRNA expression that contributes to the prevention of atherosclerosis.

APPROACH AND RESULTS

CoQ10 treatment suppressed oxidized low-density lipoprotein-induced macrophage foam cell formation by ameliorating the binding of activator protein-1 to the putative promoter region of miR-378 primary transcript, thus decreasing the miR-378 level and enhancing the ATP-binding cassette transporter G1-mediated macrophage cholesterol efflux to high-density lipoprotein. Subsequently, the axis of activator protein-1/miR-378/ATP-binding cassette transporter G1 cholesterol efflux was confirmed in peritoneal macrophages isolated from CoQ10-treated apolipoprotein E-deficient mice. Finally, CoQ10 consumption promoted macrophage reverse cholesterol transport and inhibited the progression of atherosclerosis in apolipoprotein E-deficient mice.

CONCLUSIONS

This study identified activator protein-1/miR-378/ATP-binding cassette transporter G1 as a novel cascade for CoQ10 in facilitating macrophage cholesterol efflux in vitro and in vivo. Our data thus imply that both CoQ10 and miR-378 are promising candidates for atherosclerosis prevention and treatment.

Coenzyme Q10 supplementation and diastolic heart functions in hemodialysis patients: a randomized double-blind placebo-controlled trial

Coenzyme Q10 (CoQ10) supplementation has been shown to improve diastolic heart function in various patient cohorts. Systolic and diastolic dysfunctions are common in patients with end-stage renal disease. Favorable effects of CoQ10 on cardiac functions are yet to be seen in hemodialysis patients. We aimed to evaluate effect of CoQ10 supplementation on diastolic function in a cohort of maintenance hemodialysis patients. This was a prospective, double-blind, placebo-controlled, crossover study in which all patients received placebo and oral CoQ10 200 mg/d during the 8 weeks in each phase, with a 4-week washout period. Participants underwent conventional and tissue Doppler echocardiography before and after each study phase. Parameters characterizing left ventricle diastolic function and other standard echocardiographic measurements were recorded. Twenty-eight patients were randomized, but 22 patients completed study protocol. Intraventricular septum (IVS) thickness and left ventricle mass were significantly decreased in CoQ10 group (P = 0.03 and P = 0.01, respectively). Myocardial peak systolic and early diastolic velocities derived from IVS were significantly increased (P = 0.048 and P = 0.04, respectively). Isovolumetric relaxation time and E/Em ratio calculated for IVS also significantly reduced in CoQ10 group (p = 0.02 and p = 0.04, respectively). There was no significant difference in any of the studied echocardiographic parameters in placebo group. The results of this study showed that CoQ10 supplementation did not significantly improved diastolic heart functions compared with placebo in maintenance hemodialysis patients.

Coenzyme Q10 concentration in plasma and blood cells of juvenile patients hospitalized for anorexia nervosa

The antioxidant status of coenzyme Q10 (CoQ10) was investigated in plasma, erythrocytes, and platelets of juvenile patients with anorexia nervosa. Blood for analysis of the CoQ10 status was taken from 16 juvenile patients suffering from anorexia nervosa (restricting form) at the time point of admission to the hospital and at discharge after about 12 weeks. Plasma and blood cells isolated by a density gradient were stored at -84 °C until analysis. CoQ10 concentration and redox status were measured by high pressure liquid chromatography with electrochemical detection and internal standardization. The improvement of physical health during the hospital refeeding process was followed up by the body mass index (BMI). The antioxidant status of plasma CoQ10 in juvenile patients suffering from anorexia nervosa indicated no abnormalities in comparison to healthy controls. However, the decreased concentration of CoQ10 observed in platelets at the time point of hospital admission may represent mitochondrial CoQ10 depletion. This initial deficit improved during the hospital refeeding process. The platelet CoQ10 concentration showed a positive correlation to the BMI of the patients.

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

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

Coenzyme Q(10) in male infertility: physiopathology and therapy

Both the bioenergetic and the antioxidant role of CoQ(10) suggest a possible involvement in sperm biochemistry and male infertility. CoQ(10) can be quantified in seminal fluid, where its concentration correlates with sperm count and motility. It was found that distribution of CoQ(10) between sperm cells and seminal plasma was altered in varicocele patients, who also presented a higher level of oxidative stress and lower total antioxidant capacity. The effect of vericocelectomy on partially reversing these biochemical abnormalities is discussed. The redox status of coenzyme Q(10) in seminal fluid was also determined: an inverse correlation was found between ubiquinol/ubiquinone ratio and hydroperoxide levels and between this ratio and the percentage of abnormal sperm forms. After the first in vitro observations CoQ(10) was administered to infertile patients affected by idiopathic asthenozoospermia, originally in an open label study and then in three randomized placebo-controlled trials; doses were around 200-300 mg/day and treatment lasted 6 months. A significant increase in the concentration of CoQ(10) was found, both in seminal plasma and sperm cells. Treatment also led to a certain improvement in sperm motility. In one of the studies there was also a decrease in plasma levels of follicle stimulating horhone (FSH) and luteinizine horhone (LH). Administration of CoQ(10) may play a positive role in the treatment of asthenozoospermia, possibly related to not only to its function in the mitochondrial respiratory chain but also to its antioxidant properties. Further studies are needed in order to determine whether there is also an effect on fertility rate.

Coenzyme Q10 improves seminal oxidative defense but does not affect on semen parameters in idiopathic oligoasthenoteratozoospermia: a randomized double-blind, placebo controlled trial

BACKGROUND

Several lines of evidence show the implication of oxidative stress in the etiology of male infertility. Recently, the role of coenzyme Q10 (CoQ10) in the prevention and treatment of disease has been intensively probed. However, definitive efficacy studies in oligoasthenoteratozoospermia (OAT) have not been completed yet.

AIM

To evaluate the effect of CoQ10 supplementation on semen parameters in idiopathic OAT (iOAT).

MATERIAL/SUBJECTS AND METHODS

A double-blind placebo controlled clinical trial was carried out. A total of 47 infertile men with iOAT were randomly assigned to receive 200 mg CoQ10 daily or placebo during a 12- week period. Semen parameters were determined using microscopic evaluation according to World Health Organization guidelines. Lipid peroxidation was assessed by measuring the concentration of plasma malondialdehyde. We evaluated the total antioxidant capacity of seminal plasma. To compare variables between and within the 2 groups we used independent t-test and Paired t-test.

RESULTS

The trial showed non-significant changes in semen parameters of CoQ10 group. However, concentrations of thiobarbituric acid-reactive substances were significantly (p<0.05) reduced in serum of treated groups compared with the control. Furthermore, total antioxidant capacity of seminal plasma significantly increased in the CoQ10 group (p<0.05).

CONCLUSION

Our results provide further evidence suggesting that CoQ10 supplementation is associated with alleviating oxidative stress, although it does not show any significant effects on sperm concentration, motility and morphology. It may be suggested that CoQ10 could be taken as an adjunct therapy in cases of OAT. Further studies are needed to draw a final conclusion.

Effect of coenzyme Q10 on ischemia and neuronal damage in an experimental traumatic brain-injury model in rats

BACKGROUND

Head trauma is one of the most important clinical issues that not only can be fatal and disabling, requiring long-term treatment and care, but also can cause heavy financial burden. Formation or distribution of free oxygen radicals should be decreased to enable fixing of poor neurological outcomes and to prevent neuronal damage secondary to ischemia after trauma. Coenzyme Q₁₀ (CoQ₁₀), a component of the mitochondrial electron transport chain, is a strong antioxidant that plays a role in membrane stabilization. In this study, the role of CoQ₁₀ in the treatment of head trauma is researched by analyzing the histopathological and biochemical effects of CoQ₁₀ administered after experimental traumatic brain injury in rats. A traumatic brain-injury model was created in all rats. Trauma was inflicted on rats by the free fall of an object of 450 g weight from a height of 70 cm on the frontoparietal midline onto a metal disc fixed between the coronal and the lambdoid sutures after a midline incision was carried out.

RESULTS

In the biochemical tests, tissue malondialdehyde (MDA) levels were significantly higher in the traumatic brain-injury group compared to the sham group (p < 0.05). Administration of CoQ₁₀ after trauma was shown to be protective because it significantly lowered the increased MDA levels (p < 0.05). Comparing the superoxide dismutase (SOD) levels of the four groups, trauma + CoQ₁₀ group had SOD levels ranging between those of sham group and traumatic brain-injury group, and no statistically significant increase was detected. Histopathological results showed a statistically significant difference between the CoQ₁₀ and the other trauma-subjected groups with reference to vascular congestion, neuronal loss, nuclear pyknosis, nuclear hyperchromasia, cytoplasmic eosinophilia, and axonal edema (p < 0.05).

CONCLUSION

Neuronal degenerative findings and the secondary brain damage and ischemia caused by oxidative stress are decreased by CoQ₁₀ use in rats with traumatic brain injury.

Coenzyme Q plays opposing roles on bacteria/fungi and viruses in Drosophila innate immunity

Coenzyme Q (CoQ or ubiquinone) is a lipid-soluble component of virtually all types of cell membranes and has been shown to play multiple metabolic functions. Several clinical diseases including encephalomyopathy, cerebellar ataxia and isolated myopathy were shown to be associated with CoQ deficiency. However, the role of CoQ in immunity has not been defined. In the present study, we showed that flies defective in CoQ biosynthetic gene coq2 were more susceptible to bacterial and fungal infections, while were more resistant to viruses. We found that Drosophila contained both CoQ9 and CoQ10, and food supplement of CoQ10 could partially rescue the impaired immune functions of coq2 mutants. Surprisingly, wild-type flies fed CoQ10 became more susceptible to viral infection, which suggested that extra caution should be taken when using CoQ10 as a food supplement. We further showed that CoQ was essential for normal induction of anti-microbial peptides and amplification of viruses. Our work determined CoQ content in Drosophila and described its function in immunity for the first time.

Carnitine and coenzyme Q10 levels in individuals with Prader-Willi syndrome

Carnitine deficiency or coenzyme Q10 (CoQ10) deficiency may present with hypotonia, poor growth, easy fatigability, and apnea. This constellation of findings can also be seen in individuals with Prader-Willi syndrome (PWS). Animal studies indicate that increased fat mass due to obesity negatively correlates with both carnitine and CoQ10 levels in skeletal muscle. Increased body fat and obesity are characteristic of individuals with PWS. Currently, there is no documentation of serum carnitine levels, and only one study investigating plasma CoQ10 levels, in individuals with PWS. Fasting serum carnitine and plasma CoQ10 levels were measured in 40 individuals with molecularly confirmed PWS (ages 1-27 years; 19 F/21 M), 11 individuals with early-onset morbid obesity of unknown etiology (ages 3-13 years; 5 F/6 M), and 35 control siblings from both groups (ages 1-24 years; 19 F/16 M). There were no significant differences among the three groups in either total carnitine, free carnitine, or CoQ10 levels. However, individuals with PWS had higher serum levels of carnitine esters (P = 0.013) and higher ester-to-free carnitine ratios (P = 0.0096) than controls suggesting a possible underlying impairment of peripheral carnitine utilization and mitochondrial energy metabolism in some individuals with PWS. Serum sampling identified no significant differences in total and free carnitine or CoQ10 levels between individuals with PWS, obese individuals, and sibling control groups. Muscle biopsy or measurement in leukocytes or cultured skin fibroblasts could be a better method to identify abnormalities in carnitine and CoQ10 metabolism in individuals with PWS than peripheral blood sampling.

Hormones and antioxidant systems: role of pituitary and pituitary-dependent axes

Oxidative stress, a condition defined as unbalancing between production of free radicals and antioxidant defenses, is an important pathogenetic mechanism in different diseases. Despite the abundant literature, many aspects of hormone role in regulating antioxidant synthesis and activity still remain obscure. Therefore, we reviewed experimental data, in vivo and in vitro, about the effects of the different pituitary- dependent axes on antioxidant levels, trying to give a broad view from hormones which also have antioxidant properties to the classic antioxidants, from the lipophilic antioxidant Coenzyme Q10, strictly related to thyroid function, to total antioxidant capacity, a measure of non-protein non-enzymatic antioxidants in serum and other biological fluids. Taken together, these data underline the importance of oxidative stress in various pituitary-dependent disorders, suggesting a possible clinical usefulness of antioxidant molecules.

Enhancement of shortening velocity, power, and acto-myosin crossbridge (CB) kinetics following long-term treatment with propionyl-L-carnitine, coenzyme Q10, and omega-3 fatty acids in BIO TO-2 cardiomyopathic Syrian hamsters papillary muscle

Impaired functions of myocardial muscle cells in human and animals, is a primary defect associated with idiopathic dilated cardiomyopathy (DCM). The pathophysiological mechanisms implicated in the DCM are yet to be clarified and an effective therapy is still not available. The BIO TO-2 cardiomyopathic Syrian Hamsters (CMSHs) represent an animal model of idiopathic DCM. The aim of this study was to investigate the effect of long-term treatment (2 months) with propionyl-L-carnitine (PLC), coenzyme Q(10), omega-3 fatty acids and a combination of these three agents (formulation HS12607) on mechanical properties and acto-myosin crossbridges (CBs) kinetics of left ventricular (LV) papillary muscle from control and treated 10 month old BIO TO-2 CMSHs. Isometric and isotonic contractile properties of isolated papillary muscle from control and treated CMSHs were investigated, and acto-myosin CB number, force and kinetics were calculated using Huxley's equations. Mechanical parameter values were higher in treated than in control hamsters, particularly when substances were administered together in a coformulation (HS12607). Compared to control, HS12607-treated papillary muscles showed a significant increase of maximum peak isometric tension (P(o)) (30.06 +/- 4.91 vs. 19.74 +/- 5.00 mN/mm(2)), maximum extent of muscle shortening (0.13 +/- 0.03 vs. 0.07 +/- 0.02 L/L(max)), maximum unloaded shortening velocity (1.18 +/- 0.24 vs. 0.53 +/- 0.13 L/L(max) s(-1)) and maximum peak of power output (5.52 +/- 1.61 vs. 1.58 +/- 0.83). The curvature of the hyperbolic force-velocity relationships did not differ between control and treated hamsters. When compared to controls, acto-myosin CB number increased in treated hamsters [(6.67 +/- 1.91) 10(10)/mm(2) vs. (3.55 +/- 2.08) 10(10)/mm(2)], whereas the unitary force of single CB was similar in control and treated animals. The peak value of the rate constant for CB attachment (f(1)) and detachment (g(2)) was higher in treated animals when compared to control. (93.87 +/- 25.82 vs.47.28 +/- 10.88 s(-1) and 214.40 +/- 44.64 vs. 95.56 +/- 23.49 s(-1), respectively). In conclusion, the present study illustrates that supplementation with PLC, CoQ(10) and omega-3 fatty acids improved motor parameters, energetic, and CB kinetics of BIO TO-2 CMSH papillary muscle indicating that these naturally occurring substances may be a valid adjuvant to conventional therapy in DCM.

Treatment of mitochondrial disorders

Treatment of mitochondrial disorders (MIDs) is a challenge since there is only symptomatic therapy available and since only few randomized and controlled studies have been carried out, which demonstrate an effect of some of the symptomatic or supportive measures available. Symptomatic treatment of MIDs is based on mainstay drugs, blood transfusions, hemodialysis, invasive measures, surgery, dietary measures, and physiotherapy. Drug treatment may be classified as specific (treatment of epilepsy, headache, dementia, dystonia, extrapyramidal symptoms, Parkinson syndrome, stroke-like episodes, or non-neurological manifestations), non-specific (antioxidants, electron donors/acceptors, alternative energy sources, cofactors), or restrictive (avoidance of drugs known to be toxic for mitochondrial functions). Drugs which more frequently than in the general population cause side effects in MID patients include steroids, propofol, statins, fibrates, neuroleptics, and anti-retroviral agents. Invasive measures include implantation of a pacemaker, biventricular pacemaker, or implantable cardioverter defibrillator, or stent therapy. Dietary measures can be offered for diabetes, hyperlipidemia, or epilepsy (ketogenic diet, anaplerotic diet). Treatment should be individualized because of the peculiarities of mitochondrial genetics. Despite limited possibilities, symptomatic treatment should be offered to MID patients, since it can have a significant impact on the course and outcome.

Clinical aspects of coenzyme Q10: an update

The fundamental role of coenzyme Q(10) (CoQ(10)) in mitochondrial bioenergetics and its well-acknowledged antioxidant properties constitute the basis for its clinical applications, although some of its effects may be related to a gene induction mechanism. Cardiovascular disease is still the main field of study and the latest findings confirm a role of CoQ(10) in improving endothelial function. The possible relation between CoQ(10) deficiency and statin side effects is highly debated, particularly the key issue of whether CoQ(10) supplementation counteracts statin myalgias. Furthermore, in cardiac patients, plasma CoQ(10) was found to be an independent predictor of mortality. Studies on CoQ(10) and physical exercise have confirmed its effect in improving subjective fatigue sensation and physical performance and in opposing exercise-related damage. In the field of mitochondrial myopathies, primary CoQ(10) deficiencies have been identified, involving different genes of the CoQ(10) biosynthetic pathway; some of these conditions were found to be highly responsive to CoQ(10) administration. The initial observations of CoQ(10) effects in Parkinson's and Huntington's diseases have been extended to Friedreich's ataxia, where CoQ(10) and other quinones have been tested. CoQ(10) is presently being used in a large phase III trial in Parkinson's disease. CoQ(10) has been found to improve sperm count and motility on asthenozoospermia. Moreover, for the first time CoQ(10) was found to decrease the incidence of preeclampsia in pregnancy. The ability of CoQ(10) to mitigate headache symptoms in adults was also verified in pediatric and adolescent populations.

Coenzyme Q10 treatment reduces lipid peroxidation, inducible and endothelial nitric oxide synthases, and germ cell-specific apoptosis in a rat model of testicular ischemia/reperfusion injury

In this experimental study, we assessed the preventive effects of coenzyme Q(10) (CoQ(10)) in a rat model of ischemia/reperfusion injury. The results of this study show that CoQ(10) administration before the reperfusion period of testicular torsion provides a significant decrease in testicular lipid peroxidation products and expressions of inducible nitric oxide synthase, endothelial nitric oxide synthase, and germ cell-specific apoptosis.

Coenzyme Q10: Absorption, tissue uptake, metabolism and pharmacokinetics

Available data on the absorption, metabolism and pharmacokinetics of coenzyme Q10 (CoQ10) are reviewed in this paper. CoQ10 has a fundamental role in cellular bioenergetics. CoQ10 is also an important antioxidant. Because of its hydrophobicity and large molecular weight, absorption of dietary CoQ10 is slow and limited. In the case of dietary supplements, solubilized CoQ10 formulations show enhanced bioavailability. The T(max) is around 6 h, with an elimination half-life of about 33 h. The reference intervals for plasma CoQ10 range from 0.40 to 1.91 micromol/l in healthy adults. With CoQ10 supplements there is reasonable correlation between increase in plasma CoQ10 and ingested dose up to a certain point. Animal data show that CoQ10 in large doses is taken up by all tissues including heart and brain mitochondria. This has implications for therapeutic applications in human diseases, and there is evidence for its beneficial effect in cardiovascular and neurodegenerative diseases. CoQ10 has an excellent safety record.

Coenzyme Q10 and male infertility

We had previously demonstrated that Coenzyme Q10 [(CoQ10) also commonly called ubiquinone] is present in well-measurable levels in human seminal fluid, where it probably exerts important metabolic and antioxidant functions; seminal CoQ10 concentrations show a direct correlation with seminal parameters (count and motility). Alterations of CoQ10 content were also shown in conditions associated with male infertility, such as asthenozoospermia and varicocele (VAR). The physiological role of this molecule was further clarified by inquiring into its variations in concentrations induced by different medical or surgical procedures used in male infertility treatment. We therefore evaluated CoQ10 concentration and distribution between seminal plasma and spermatozoa in VAR, before and after surgical treatment, and in infertile patients after recombinant human FSH therapy. The effect of CoQ10 on sperm motility and function had been addressed only through some in vitro experiments. In two distinct studies conducted by our group, 22 and 60 patients affected by idiopathic asthenozoospermia were enrolled, respectively. CoQ10 and its reduced form, ubiquinol, increased significantly both in seminal plasma and sperm cells after treatment, as well as spermatozoa motility. A weak linear dependence among the relative variations, at baseline and after treatment, of seminal plasma or intracellular CoQ10, ubiquinol levels and kinetic parameters was found in the treated group. Patients with lower baseline value of motility and CoQ10 levels had a statistically significant higher probability to be responders to the treatment. In conclusion, the exogenous administration of CoQ10 increases both ubiquinone and ubiquinol levels in semen and can be effective in improving sperm kinetic features in patients affected by idiopathic asthenozoospermia.

Supplementation of coenzyme Q10 and alpha-tocopherol lowers glycated hemoglobin level and lipid peroxidation in pancreas of diabetic rats

The importance of nutritional supplementation in diabetes remains an unresolved issue. The present study was undertaken to examine the effects of alpha-tocopherol and CoQ(10), powerful antioxidants, on metabolic control and on the pancreatic mitochondria of GK rats, a model of type 2 diabetes. We also evaluated the efficacy of these nutrients in preventing the diabetic pancreatic lesions observed in GK rats. Rats were divided into 4 groups, a control group of diabetic GK rats and 3 groups of GK rats administered with alpha-tocopherol and CoQ(10) alone or both in association, during 8 weeks. Fasting blood glucose levels were not significantly different between the groups, nor were blood glucose levels at 2 hours after a glucose load. HbA1c level was significantly reduced in the group supplemented with both antioxidants. Diabetes induced a decrease in coenzyme Q plasma levels that prevailed after treatment with antioxidants. In addition, the plasma alpha-tocopherol levels were higher after treatment with the antioxidants. An increment in some components of the antioxidant defense system was observed in pancreatic mitochondria of treated GK rats. Moreover, the antioxidants tested either alone or in association failed to prevent the pancreatic lesions in this animal model of type 2 diabetes. In conclusion, our results indicate that CoQ(10) and alpha-tocopherol decrease glycated HbA1c and pancreatic lipid peroxidation. These antioxidants increase some components of the antioxidant defense system but do not prevent pancreatic lesions. Thus, we cannot rule out the potential benefit of antioxidant treatments in type 2 diabetes in the prevention of their complications.

Water-soluble Coenzyme Q10 formulation (Q-ter) promotes outer hair cell survival in a guinea pig model of noise induced hearing loss (NIHL)

The mitochondrial respiratory chain is a powerful source of reactive oxygen species (ROS) also in noise induced hearing loss (NIHL) and anti-oxidants and free-radicals scavengers have been shown to attenuate the damage. Coenzyme Q(10) (CoQ(10)) or ubiquinone has a bioenergetic role as a component of the mithocondrial respiratory chain, it inhibits mitochondrial lipid peroxidation, inducing ATP production and it is involved in ROS removal and prevention of oxidative stress-induced apoptosis. However the therapeutic application of CoQ(10) is limited by the lack of solubility and poor bio- availability, therefore it is a challenge to improve its water solubility in order to ameliorate the efficacy in tissues and fluids. This study was conducted in a model of acoustic trauma in the guinea pig where the effectiveness of CoQ(10) was compared with a soluble formulation of CoQ(10) (multicomposite CoQ(10) Terclatrate, Q-ter) given intraperitoneally 1 h before and once daily for 3 days after pure tone noise exposure (6 kHz for 1 h at 120 dB SPL). Functional and morphological studies were carried out by measuring auditory brainstem responses, scanning electron microscopy for hair cell loss count, active caspase 3 staining and terminal deoxynucleotidyl transferase-mediated dUTP labelling assay in order to identify initial signs of apoptosis. Treatments decreased active caspase 3 expression and the number of apoptotic cells, but animals injected with Q-ter showed a greater degree of activity in preventing apoptosis and thus in improving hearing. These data confirm that solubility of Coenzyme Q(10) improves the ability of CoQ(10) in preventing oxidative injuries that result from mitochondrial dysfunction.

The effect of coenzyme Q10 on the pharmacokinetic parameters of theophylline

Interaction of a drug with other drugs and dietary supplements is becoming an emerging issue for patients and health insurance authorities due to awareness of adverse drug event. In this study, we examined the effects of coenzyme Q10 (CoQ10), one of the most popular dietary supplements, on the pharmacokinetic parameters of theophylline in rats. The pharmacokinetic parameters of theophylline changed significantly when the drug was administered after five consecutive days of pretreatment with CoQ10. Time to reach maximum plasma concentration of theophylline delayed when the drug was administered after the pretreatment with CoQ10. Maximum plasma concentration and area under the curve of theophylline were about two-fold increased and other pharmacokinetic parameters such as half-life and volume of distribution were also changed significantly. Therefore, although CoQ10 is generally considered a safe dietary supplement, it appears that patients on theophylline therapy should use caution when they take CoQ10.

Toxicity of coenzyme Q(10): a report of 90-day repeated dose toxicity study in rats

Potential toxicity of CoQ(10) was studied in rats by oral gavage for 90 days at 500, 1500, and 3000 mg/kg.day. A 15-day recovery period after the administration period was investigated. Body weight and food consumption were measured throughout the study. Meanwhile, clinical observations were recorded. Hematological and blood chemistry parameters were evaluated at both the end of the dosing period and the end of the recovery period. Gross-pathologic and histopathologic examination was performed on select tissues from all animals. No adverse changes in mortality and clinical signs occurred. The body weights of males in the 1500 mg/kg dosage group were slightly reducted; likewise, the food consumption in 3000 mg/kg female rats decreased, but this is not a dose-dependent behavior. Significant change of liver function (TRIGL) and CHOL did not show a dose-dependent effect. Weight of ovary and ovary-to-body weight ratio decreased in the 1500 mg/kg dosage groups. Meanwhile, the uterus -to-body weight ratio increased the in 3000 mg/kg dosage groups. However, there were no significant histopathological changes observed in ovary and uterus: so they were not considered to be adverse. It suggested that CoQ(10) is relatively safe on the test dosage administration. Nevertheless, appetite the body weight, blood lipid and liver function should be observed during long-term clinical administration of this drug with high dosage. Overall, CoQ(10) was well tolerated by male and female rats at dose levels up to 3000 mg/kg.day.

Positive inotropic effect of coenzyme Q10, omega-3 fatty acids and propionyl-L-carnitine on papillary muscle force-frequency responses of BIO TO-2 cardiomyopathic Syrian hamsters

The inability of heart muscle to generate ventricular pressure to adequately propel blood through the cardiovascular system is a primary defect associated with congestive heart failure (CHF). Force-frequency relationship (FFR) is one of the main cardiac defects associated with congestive heart failure. Thus FFR is a convenient methodological tool for evaluating the severity of muscle contractile dysfunction and the effectiveness of therapeutic agents. Papillary muscle isolated from BIO TO-2 cardiomyopathic Syrian hamsters (CMSHs), show a depressed FFR and represents an animal model of human idiopathic dilated cardiomyopathy. In the present study we investigated the effect of CoQ10, omega-3 fatty acids, propionyl-L-carnitine (PLC) and a combination of these 3 agents (formulation HS12607) on FFR in 8 month old BIO TO-2 CMSHs. Papillary muscles isolated from the anesthetized animals were placed in an incubation bath and attached to an isometric force transducer. A digital computer with an analog/digital interface allowed control of both muscle developed force and electrical stimulus parameters. Force-frequency response was evaluated, at Lmax, with increasing frequencies: 0.06, 0.12, 0.25, 0.5, 1, 2 and 4 Hz. HS12607-treatment produced a positive inotropic effect resulting in a significant enhancement (p < 0.05) of the peak force at the highest frequencies (1-4 Hz). In the range of frequency of 1-4 Hz also CoQ10 and omega-3 significantly (p < 0.05) attenuated the fractional decline in developed force. The significant improvement (p < 0.05) of the timing parameter peak rate of tension rise (+ T') and peak rate of tension fall (-T') indicating a faster rate of muscle contraction and relaxation respectively, found in CoQ10, omega-3 and PLC-treated CMSHs, may be due to the positive effects of these substances on sarcoplasmic reticulum functions. These findings suggest that naturally occurring CoQ10, omega-3 and PLC, particularly when administered together in a coformulation, might be a valid adjuvant to conventional therapy in dilated cardiomyopathy especially when considering that they are natural substances, devoid of side effects.

Functions of coenzyme Q10 in inflammation and gene expression

Clinical studies demonstrated the efficacy of Coenzyme Q10 (CoQ10) as an adjuvant therapeutic in cardiovascular diseases, mitochondrial myopathies and neurodegenerative diseases. More recently, expression profiling revealed that Coenzyme Q10 (CoQ10) influences the expression of several hundred genes. To unravel the functional connections of these genes, we performed a text mining approach using the Genomatix BiblioSphere. We identified signalling pathways of G-protein coupled receptors, JAK/STAT, and Integrin which contain a number of CoQ10 sensitive genes. Further analysis suggested that IL5, thrombin, vitronectin, vitronectin receptor, and C-reactive protein are regulated by CoQ10 via the transcription factor NFkappaB1. To test this hypothesis, we studied the effect of CoQ10 on the NFkappaB1-dependent pro-inflammatory cytokine TNF-alpha. As a model, we utilized the murine macrophage cell lines RAW264.7 transfected with human apolipoprotein E3 (apoE3, control) or pro-inflammatory apoE4. In the presence of 2.5 microM or 75 microM CoQ10 the LPS-induced TNF-alpha response was significantly reduced to 73.3 +/- 2.8% and 74.7 +/- 8.9% in apoE3 or apoE4 cells, respectively. Therefore, the in silico analysis as well as the cell culture experiments suggested that CoQ10 exerts anti-inflammatory properties via NFkappaB1-dependent gene expression.

The uptake and distribution of coenzyme Q(10)

This review describes recent advances in our understanding of the uptake and distribution of coenzyme Q10 (CoQ10) in cells, animals, and humans. These advances have provided evidence of important pharmacokinetic factors, such as non-linear absorption and enterohepatic recirculation, and may facilitate the development of new CoQ10 formulations. Studies providing data which support the claim of tissue uptake of exogenous CoQ10 are also discussed. Improved CoQ10 dosing and drug level monitoring guidelines are suggested for adult and pediatric patient populations. Future CoQ10 research should consider uptake and distribution factors to determine cost-benefit relationships.