Coenzyme Q(10)--its role as a prooxidant in the formation of superoxide anion/hydrogen peroxide and the regulation of the metabolome

Coenzyme Q10 prevents RANKL-induced osteoclastogenesis by promoting autophagy via inactivation of the PI3K/AKT/mTOR and MAPK pathways

Coenzyme Q10 (CoQ10) is a potent antioxidant that is implicated in the inhibition of osteoclastogenesis, but the underlying mechanism has not been determined. We explored the underlying molecular mechanisms involved in this process. RAW264.7 cells received receptor activator of NF-κB ligand (RANKL) and CoQ10, after which the differentiation and viability of osteoclasts were assessed. After the cells were treated with CoQ10 and/or H2O2 and RANKL, the levels of reactive oxygen species (ROS) and proteins involved in the PI3K/AKT/mTOR and MAPK pathways and autophagy were tested. Moreover, after the cells were pretreated with or without inhibitors of the two pathways or with the mitophagy agonist, the levels of autophagy-related proteins and osteoclast markers were measured. CoQ10 significantly decreased the number of TRAP-positive cells and the level of ROS but had no significant impact on cell viability. The relative phosphorylation levels of PI3K, AKT, mTOR, ERK, and p38 were significantly reduced, but the levels of FOXO3/LC3/Beclin1 were significantly augmented. Moreover, the levels of FOXO3/LC3/Beclin1 were significantly increased by the inhibitors and mitophagy agonist, while the levels of osteoclast markers showed the opposite results. Our data showed that CoQ10 prevented RANKL-induced osteoclastogenesis by promoting autophagy via inactivation of the PI3K/AKT/mTOR and MAPK pathways in RAW264.7 cells.

Antioxidative Stress-Induced Destruction to Cochlear Cells Caused by Blind Antioxidant Therapy

OBJECTIVE

Verification that blind and excessive use of antioxidants leads to antioxidant stress which exacerbates cochlear cell damage.

STUDY DESIGN

Basic research.

SETTING

The Third Affiliated Hospital of Sun Yat-Sen University.

METHODS

We compared and quantified hair cell-like house ear institute-organ of corti 1 (HEI-OC1) cell density, cell viability, and apoptosis caused by different concentrations of N-acetylcysteine (NAC) via Hoechst staining, Cell Counting Kit 8, Hoechst with propidium iodide staining, and Annexin V with propidium iodide (PI) staining. Apoptosis induced by high concentrations of M40403 and coenzyme Q10 in cochlear explants was analyzed and compared by cochlear dissection and activated caspase 3 labeling.

RESULTS

With the increase of NAC concentration (0-1000 μmol/L), cell density decreased consequently and reached the lowest at 1000 μmol/L (****P ≤ .0001). Cell viability is also declining (**P < .01). The number of Annexin V-fluorescein isothiocyanate-labeled cells and PI-labeled cells increased with increasing NAC concentration after treatment of HEI-OC1 cells for 48 hours. The proportion of apoptotic cells also rose (*P < .05, **P < .01). Cochlear hair cells (HCs) treated with low concentrations of M40403 and coenzyme Q10 for 48 hours showed no damage. When the concentrations of M40403 and coenzyme Q10 were increased (concentrations＞30 μmol/L), HC damage began, followed by a dose-dependent increase in HC loss (*P < .001, **P < .0001). Activated caspase-3 was clearly apparent in cochlear explants treated with 50 μmol/L M40403 and coenzyme Q10 compared with cochlear explants without added M40403 and coenzyme Q10.

CONCLUSION

These experimental results suggest that inappropriate application of antioxidants can cause severe damage to normal cochlear HCs.

CoQ10 and Mitochondrial Dysfunction in Alzheimer's Disease

The progress in understanding the pathogenesis and treatment of Alzheimer's disease (AD) is based on the recognition of the primary causes of the disease, which can be deduced from the knowledge of risk factors and biomarkers measurable in the early stages of the disease. Insights into the risk factors and the time course of biomarker abnormalities point to a role for the connection of amyloid beta (Aβ) pathology, tau pathology, mitochondrial dysfunction, and oxidative stress in the onset and development of AD. Coenzyme Q10 (CoQ10) is a lipid antioxidant and electron transporter in the mitochondrial electron transport system. The availability and activity of CoQ10 is crucial for proper mitochondrial function and cellular bioenergetics. Based on the mitochondrial hypothesis of AD and the hypothesis of oxidative stress, the regulation of the efficiency of the oxidative phosphorylation system by means of CoQ10 can be considered promising in restoring the mitochondrial function impaired in AD, or in preventing the onset of mitochondrial dysfunction and the development of amyloid and tau pathology in AD. This review summarizes the knowledge on the pathophysiology of AD, in which CoQ10 may play a significant role, with the aim of evaluating the perspective of the pharmacotherapy of AD with CoQ10 and its analogues.

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

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

The influence of dietary Coenzyme Q10 on growth performance, antioxidant capacity and resistance against Aeromonas hydrophila of juvenile European eel (Anguilla anguilla)

The present study was conducted to investigate the effects of dietary Coenzyme Q10 (CoQ10) on the growth performance, body composition, digestive enzyme activity, antioxidant capacity, intestinal histology, immune-antioxidant gene expression and disease resistance of juvenile European eel (Anguilla anguilla). Fish were fed a diet supplemented with CoQ10 at concentrations of 0, 40, 80 and 120 mg/kg for 56 days. The results indicated that dietary CoQ10 supplementation did not significantly affect final body weight (FBW), survival rate (SR), weight gain (WG), feed rate (FR), viscerosomatic index (VSI) or hepatosomatic index (HSI) among all experimental groups. However, the highest FBW, WG and SR were found in the 120 mg/kg CoQ10 group. Dietary 120 mg/kg CoQ10 markedly improved feed efficiency (FE) and the protein efficiency ratio (PER). The crude lipids in the body and triglycerides (TG) and total cholesterol (TC) in serum were obviously lower in the 120 mg/kg CoQ10 group than in the control group. For digestive enzymes, protease activity in the intestine was markedly boosted in the 120 mg/kg CoQ10 group. The serum activities of SOD, CAT and GST in the 120 mg/kg CoQ10 group were significantly higher than those in the control group. Dietary 120 mg/kg CoQ10 efficiently enhanced superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione S-transferase (GST) activities in the liver, while the malondialdehyde (MDA) content was significantly decreased. No significant histological changes in the liver were identified in any group. Dietary supplementation with 120 mg/kg CoQ10 improved antioxidant capacity and immunity by upregulating the expression of cyp1a, sod, gst, lysC, igma1, igmb1 and irf3 in the liver. Furthermore, the cumulative survival rate of juvenile European eel against challenge with Aeromonas hydrophila was significantly elevated in the 80 and 120 mg/kg CoQ10 supplemented groups. Conclusively, our study suggested that supplementing the diet of juvenile European eel with CoQ10 at a concentration of 120 mg/kg could promote their feed utilization, fat reduction, antioxidant capacity, digestibility, immune-antioxidant gene expression and resistance to Aeromonas hydrophila without negative effects on fish health status.

Effect of dietary antioxidant supplements (selenium forms, alpha-tocopherol, and coenzyme Q10) on growth performance, immunity, and physiological responses in rainbow trout (Oncorhynchus mykiss) using orthogonal array design

Dietary supplements containing antioxidants play an important role in reducing the risk of peroxidative attack in aquatic animals. In this work, an orthogonal array design (L9: 3⁴) was used to evaluate the effect of four dietary antioxidant supplements on the physiological responses of rainbow trout at three levels. The supplements included different (A) selenium (Se) forms (inorganic, organic, and nanoparticle), (B) Se content (0, 0.3, & 0.5 mg/kg feed), (C) vitamin E (VE) content (0, 100, & 150 mg/kg feed), and (D) coenzyme Q10 (CoQ10) content (0, 10, & 20 mg/kg feed). Fish with an average body weight of 8.35 ± 0.33 g were randomly allocated to different experimental groups. According to the results, the antioxidant supplements included in the diet had no significant effects on the growth performance of fish (P > 0.05). Immunological and antioxidant parameters were mainly improved by the Se form (Nano-Se) and dietary CoQ10 supplementation. In addition, Se form and VE were more effective in digestive enzyme activities and hematology indices in comparison to other dietary antioxidants. Additionally, diets supplemented with nano-Se along with CoQ10 and VE improved fish resistance/stamina against stress. In conclusion, a more effective combination of the four antioxidant supplements was A_2/3B_2/3C₃D₃ (i.e., 0.5 mg/kg organic/nano-Se, 150 mg/kg VE, and 20 mg/kg CoQ10), which could mainly improve the physiological responses of rainbow trout.

Biomolecules resveratrol + coenzyme Q10 recover the cell state of human mesenchymal stem cells after 1-methyl-4-phenylpyridinium-induced damage and improve proliferation and neural differentiation

Neurodegenerative disorders are a critical affection with a high incidence around the world. Currently, there are no effective treatments to solve this problem. However, the application of mesenchymal stem cells (MSCs) and antioxidants in neurodegenerative diseases has shown to be a promising tool due to their multiple therapeutic effects. This work aimed to evaluate the effects of a combination of resveratrol (RSV) and coenzyme Q10 (CoQ10) on the proliferation and differentiation of MSC and the protector effects in induced damage. To characterize the MSCs, we performed flow cytometry, protocols of cellular differentiation, and immunocytochemistry analysis. The impact of RSV + CoQ10 in proliferation was evaluated by supplementing 2.5 and 10 μM of RSV + CoQ10 in a cellular kinetic for 14 days. Cell viability and lactate dehydrogenase levels (LDH) were also analyzed. The protective effect of RSV + CoQ10 was assessed by supplementing the treatment to damaged MSCs by 1-methyl-4-phenylpyridinium (MPP+); cellular viability, LDH, and reactive oxygen species (ROS) were evaluated.. MSCs expressed the surface markers CD44, CD73, CD90, and CD105 and showed multipotential ability. The combination of RSV + CoQ10 increased the proliferation potential and cell viability and decreased LDH levels. In addition, it reverted the effect of MPP+-induced damage in MSCs to enhance cell viability and decrease LDH and ROS. Finally, RSV + CoQ10 promoted the differentiation of neural progenitors. The combination of RSV + CoQ10 represents a potential treatment to improve MSCs capacities and protect against neurodegenerative damage.

Effect of Treating Eggs with Coenzyme Q10 (CoQ10) on Growth Variables, Histomorphometry, and Antioxidant Capacity in Red Tilapia (Oreochromis aureus × Oreochromis mossambicus) Larvae

Red tilapia eggs one day post fertilization (dpf) were exposed to coenzyme Q10 (CoQ10) at rates of 0, 5, and 10 mg/L for control, treatment 2 (C5), and treatment 3 (C10), respectively, without exchanging water and until the larval mouth-opening stage. Fertilized eggs of red tilapia exposed to different concentrations of CoQ10 were hatched at rates (p > 0.05) between 38 to 54.67%. The yolk-sac diameter at the 2nd day post hatching (dph), ranged from 1.85 to 1.87 mm in depth and 1.63 to 1.88 mm in width and was not altered by the CoQ10 treatments. Similarly, red tilapia survival (p > 0.05) ranged from 22.67 to 32%. On 6 dph, a slight percentage (2.08%) of survived fishes exposed to high CoQ10 dose (C10) exhibited larval deformation in the form of an axial curvature of the spine in the abdominal and caudal region. Larvae displayed a normal structure of the esophagus folds in all fish groups, and larvae in the C5 group displayed the longest folds and widest muscularis layer, followed by fishes in the C10 group and the control. Red tilapia fry on 30 dph treated with CoQ10 possessed higher antioxidant potentials in terms of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) compared to the control. In conclusion, treating Red tilapia fertile eggs with 5 mg/L CoQ10 improves the growth, gut structure, and antioxidant efficiency of the produced larvae.

HBM4EU Chromates Study: Urinary Metabolomics Study of Workers Exposed to Hexavalent Chromium

Exposure to hexavalent chromium Cr(VI) may occur in several occupational activities, placing workers in many industries at risk for potential related health outcomes. Untargeted metabolomics was applied to investigate changes in metabolic pathways in response to Cr(VI) exposure. We obtained our data from a study population of 220 male workers with exposure to Cr(VI) and 102 male controls from Belgium, Finland, Poland, Portugal and the Netherlands within the HBM4EU Chromates Study. Urinary metabolite profiles were determined using liquid chromatography mass spectrometry, and differences between post-shift exposed workers and controls were analyzed using principal component analysis. Based on the first two principal components, we observed clustering by industrial chromate application, such as welding, chrome plating, and surface treatment, distinct from controls and not explained by smoking status or alcohol use. The changes in the abundancy of excreted metabolites observed in workers reflect fatty acid and monoamine neurotransmitter metabolism, oxidative modifications of amino acid residues, the excessive formation of abnormal amino acid metabolites and changes in steroid and thyrotropin-releasing hormones. The observed responses could also have resulted from work-related factors other than Cr(VI). Further targeted metabolomics studies are needed to better understand the observed modifications and further explore the suitability of urinary metabolites as early indicators of adverse effects associated with exposure to Cr(VI).

Switching of Redox Signaling by Prdx6 Expression Decides Cellular Fate by Hormetic Phenomena Involving Nrf2 and Reactive Oxygen Species

Changes in intracellular reactive oxygen species (ROS) levels due to remodeling of antioxidant defense can affect the status of biological homeostasis in aging/oxidative stress. Peroxiredoxin 6 (Prdx6), an antioxidant gene downstream target for the Nrf2 pathway, plays a role in regulating ROS homeostasis. Using aging human (h) lens epithelial cells (LECs) or Prdx6-deficient (Prdx6^-/-) mouse (m) LECs, here we showed that dichlorofluorescein (DCF) oxidation or H₂O₂ were strictly controlled by Prdx6. We observed that a moderate degree of oxidative stress augmented Nrf2-mediated Prdx6 expression, while higher doses of H₂O₂ (≥100 µM) caused a dramatic loss of Prdx6 expression, resulting in increased DCF oxidation and H₂O₂ amplification and cell death. Mechanistically, at increased oxidative stress, Nrf2 upregulated transcriptional factor Klf9, and that Klf9 bound to the promoter and repressed the Prdx6 gene. Similarly, cells overexpressing Klf9 displayed Klf9-dependent Prdx6 suppression and DCF oxidation with H₂O₂ amplification, while ShKlf9 reversed the process. Our data revealed that H₂O₂ and DCF oxidation levels play a hormetical role, and the Nrf2-Klf9-Prdx6 pathway is pivotal for the phenomena under the conditions of oxidative load/aging. On the whole, the results demonstrate that oxidative hormetical response is essentially based on levels of oxidative triggering and the status of Klf9-Prdx6 pathway activation; thus, Klf9 can be considered as a therapeutic target for hormetic shifting of cellular defense to improve protective resilience to oxidative stress.

Coenzyme Q10 effects in neurological diseases

Coenzyme Q10 (CoQ10), a lipophilic substituted benzoquinone, is present in animal and plant cells. It is endogenously synthetized in every cell and involved in a variety of cellular processes. CoQ10 is an obligatory component of the respiratory chain in inner mitochondrial membrane. In addition, the presence of CoQ10 in all cellular membranes and in blood. It is the only endogenous lipid antioxidant. Moreover, it is an essential factor for uncoupling protein and controls the permeability transition pore in mitochondria. It also participates in extramitochondrial electron transport and controls membrane physicochemical properties. CoQ10 effects on gene expression might affect the overall metabolism. Primary changes in the energetic and antioxidant functions can explain its remedial effects. CoQ10 supplementation is safe and well-tolerated, even at high doses. CoQ10 does not cause any serious adverse effects in humans or experimental animals. New preparations of CoQ10 that are less hydrophobic and structural derivatives, like idebenone and MitoQ, are being developed to increase absorption and tissue distribution. The review aims to summarize clinical and experimental effects of CoQ10 supplementations in some neurological diseases such as migraine, Parkinson´s disease, Huntington´s disease, Alzheimer´s disease, amyotrophic lateral sclerosis, Friedreich´s ataxia or multiple sclerosis. Cardiovascular hypertension was included because of its central mechanisms controlling blood pressure in the brainstem rostral ventrolateral medulla and hypothalamic paraventricular nucleus. In conclusion, it seems reasonable to recommend CoQ10 as adjunct to conventional therapy in some cases. However, sometimes CoQ10 supplementations are more efficient in animal models of diseases than in human patients (e.g. Parkinson´s disease) or rather vague (e.g. Friedreich´s ataxia or amyotrophic lateral sclerosis).

Hydrogen Peroxide and Amyotrophic Lateral Sclerosis: From Biochemistry to Pathophysiology

Free radicals are unstable chemical reactive species produced during Redox dyshomeostasis (RDH) inside living cells and are implicated in the pathogenesis of various neurodegenerative diseases. One of the most complicated and life-threatening motor neurodegenerative diseases (MND) is amyotrophic lateral sclerosis (ALS) because of the poor understanding of its pathophysiology and absence of an effective treatment for its cure. During the last 25 years, researchers around the globe have focused their interest on copper/zinc superoxide dismutase (Cu/Zn SOD, SOD1) protein after the landmark discovery of mutant SOD1 (mSOD1) gene as a risk factor for ALS. Substantial evidence suggests that toxic gain of function due to redox disturbance caused by reactive oxygen species (ROS) changes the biophysical properties of native SOD1 protein thus, instigating its fibrillization and misfolding. These abnormal misfolding aggregates or inclusions of SOD1 play a role in the pathogenesis of both forms of ALS, i.e., Sporadic ALS (sALS) and familial ALS (fALS). However, what leads to a decrease in the stability and misfolding of SOD1 is still in question and our scientific knowledge is scarce. A large number of studies have been conducted in this area to explore the biochemical mechanistic pathway of SOD1 aggregation. Several studies, over the past two decades, have shown that the SOD1-catalyzed biochemical reaction product hydrogen peroxide (H₂O₂) at a pathological concentration act as a substrate to trigger the misfolding trajectories and toxicity of SOD1 in the pathogenesis of ALS. These toxic aggregates of SOD1 also cause aberrant localization of TAR-DNA binding protein 43 (TDP-43), which is characteristic of neuronal cytoplasmic inclusions (NCI) found in ALS. Here in this review, we present the evidence implicating the pivotal role of H₂O₂ in modulating the toxicity of SOD1 in the pathophysiology of the incurable and highly complex disease ALS. Also, highlighting the role of H₂O₂ in ALS, we believe will encourage scientists to target pathological concentrations of H₂O₂ thereby halting the misfolding of SOD1.

Structural Features of Cytochrome b5–Cytochrome b5 Reductase Complex Formation and Implications for the Intramolecular Dynamics of Cytochrome b5 Reductase

Membrane cytochrome b₅ reductase is a pleiotropic oxidoreductase that uses primarily soluble reduced nicotinamide adenine dinucleotide (NADH) as an electron donor to reduce multiple biological acceptors localized in cellular membranes. Some of the biological acceptors of the reductase and coupled redox proteins might eventually transfer electrons to oxygen to form reactive oxygen species. Additionally, an inefficient electron transfer to redox acceptors can lead to electron uncoupling and superoxide anion formation by the reductase. Many efforts have been made to characterize the involved catalytic domains in the electron transfer from the reduced flavoprotein to its electron acceptors, such as cytochrome b₅, through a detailed description of the flavin and NADH-binding sites. This information might help to understand better the processes and modifications involved in reactive oxygen formation by the cytochrome b₅ reductase. Nevertheless, more than half a century since this enzyme was first purified, the one-electron transfer process toward potential electron acceptors of the reductase is still only partially understood. New advances in computational analysis of protein structures allow predicting the intramolecular protein dynamics, identifying potential functional sites, or evaluating the effects of microenvironment changes in protein structure and dynamics. We applied this approach to characterize further the roles of amino acid domains within cytochrome b₅ reductase structure, part of the catalytic domain, and several sensors and structural domains involved in the interactions with cytochrome b₅ and other electron acceptors. The computational analysis results allowed us to rationalize some of the available spectroscopic data regarding ligand-induced conformational changes leading to an increase in the flavin adenine dinucleotide (FAD) solvent-exposed surface, which has been previously correlated with the formation of complexes with electron acceptors.

Effects of Extracellular Osteoanabolic Agents on the Endogenous Response of Osteoblastic Cells

The complex multidimensional skeletal organization can adapt its structure in accordance with external contexts, demonstrating excellent self-renewal capacity. Thus, optimal extracellular environmental properties are critical for bone regeneration and inextricably linked to the mechanical and biological states of bone. It is interesting to note that the microstructure of bone depends not only on genetic determinants (which control the bone remodeling loop through autocrine and paracrine signals) but also, more importantly, on the continuous response of cells to external mechanical cues. In particular, bone cells sense mechanical signals such as shear, tensile, loading and vibration, and once activated, they react by regulating bone anabolism. Although several specific surrounding conditions needed for osteoblast cells to specifically augment bone formation have been empirically discovered, most of the underlying biomechanical cellular processes underneath remain largely unknown. Nevertheless, exogenous stimuli of endogenous osteogenesis can be applied to promote the mineral apposition rate, bone formation, bone mass and bone strength, as well as expediting fracture repair and bone regeneration. The following review summarizes the latest studies related to the proliferation and differentiation of osteoblastic cells, enhanced by mechanical forces or supplemental signaling factors (such as trace metals, nutraceuticals, vitamins and exosomes), providing a thorough overview of the exogenous osteogenic agents which can be exploited to modulate and influence the mechanically induced anabolism of bone. Furthermore, this review aims to discuss the emerging role of extracellular stimuli in skeletal metabolism as well as their potential roles and provide new perspectives for the treatment of bone disorders.

Coenzyme Q10 ameliorates the quality of mouse oocytes during in vitro culture

Oxidative stress causes several diseases and dysfunctions in cells, including oocytes. Clearly, oxidative stress influences oocyte quality during in vitro maturation and fertilization. Here we tested the ability of coenzyme Q10 (CoQ10) to reduce reactive oxygen species (ROS) and improve mouse oocyte quality during in vitro culture. Treatment with 50 μM CoQ10 efficiently reduced ROS levels in oocytes cultured in vitro. The fertilizable form of an oocyte usually contains a cortical granule-free domain (CGFD). CoQ10 enhanced the ratio of CGFD-oocytes from 35% to 45%. However, the hardening of the zona pellucida in oocytes was not affected by CoQ10 treatment. The in vitro maturation capacity of oocytes, which was determined by the first polar body extrusion, was enhanced from 48.9% to 75.7% by the addition of CoQ10 to the culture medium. During the parthenogenesis process, the number of two-cell embryos was increased by CoQ10 from 43.5% to 67.3%. Additionally, treatment with CoQ10 increased the expression of Bcl2 and Sirt1 in cumulus cells. These results suggested that CoQ10 had a positive effect on ROS reduction, maturation rate and two-cell embryo formation in mouse oocyte culture.

Coenzyme Q10 supplementation - In ageing and disease

Coenzyme Q₁₀ (CoQ₁₀) is an essential component of the mitochondrial electron transport chain. It is also an antioxidant in cellular membranes and lipoproteins. All cells produce CoQ₁₀ by a specialized cytoplasmatic-mitochondrial pathway. CoQ₁₀ deficiency can result from genetic failure or ageing. Some drugs including statins, widely used by inter alia elderly, may inhibit endogenous CoQ₁₀ synthesis. There are also chronic diseases with lower levels of CoQ₁₀ in tissues and organs. High doses of CoQ₁₀ may increase both circulating and intracellular levels, but there are conflicting results regarding bioavailability. Here, we review the current knowledge of CoQ₁₀ biosynthesis and primary and acquired CoQ₁₀ deficiency, and results from clinical trials based on CoQ₁₀ supplementation. There are indications that supplementation positively affects mitochondrial deficiency syndrome and some of the symptoms of ageing. Cardiovascular disease and inflammation appear to be alleviated by the antioxidant effect of CoQ₁₀. There is a need for further studies and well-designed clinical trials, with CoQ₁₀ in a formulation of proven bioavailability, involving a greater number of participants undergoing longer treatments in order to assess the benefits of CoQ₁₀ treatment in neurodegenerative disorders, as well as in metabolic syndrome and its complications.

Lipid Profile and Vascular Remodelling in Young Dyslipidemic Subjects Treated with Nutraceuticals Derived from Red Yeast Rice

BACKGROUND AND AIMS

A relevant role is emerging for functional foods in cardiovascular prevention. The aim of this study was to assess the effect of a nutraceutical multitargeted approach on lipid profile and inflammatory markers along with vascular remodelling in a cohort of dyslipidemic subjects without history of cardiovascular (CV) disease.

METHODS AND RESULTS

We enrolled 25 subjects (mean age 48.2 years) with low to moderate CV risk profile and total cholesterol (TC) levels between 150 and 250 mg/dl. The patients were assigned to receive for one year a tablet/die of a nutraceutical combination containing red yeast rice (RYR) extract (Monacolin 3 mg/tablet) and coenzyme Q10 (30 mg/tablet). Treatment with the nutraceutical compounds led to a significant reduction of TC (from 227 to 201 mg/dl, p < 0.001), LDL-c (from 150 to 130 mg/dl, p = 0.001), triglycerides (from 121 to 109 mg/dl, p = 0.013), non-HDL-cholesterol (from 168 to 141 mg/dl, p < 0.001), hs-CRP (from 1.74 to 1.20 mg/l, p = 0.015), and osteoprotegerin (from 1488 to 1328 pg/ml, p = 0.045). Levels of HDL-c, Lp(a), glucose, liver enzyme, CPK, or creatinine did not change over time. An ultrasound study was performed to assess changes in mean carotid intima-media thickness (IMT) and maximum IMT (M-MAX) as well as modification in local carotid stiffness by means of determining the carotid compliance coefficient (CC) and distensibility coefficient (DC). At the end of the treatment, we observed small but significant reductions in both mean-IMT (from 0.62 to 0.57 mm, p = 0.022) and M-MAX (from 0.79 to 0.73 mm, p = 0.002), and an improvement in carotid elasticity (DC from 22.4 to 24.3 × 10-3/kPa, p = 0.006 and CC from 0.77 to 0.85 mm2/kPa, p = 0.019).

CONCLUSIONS

A long-term treatment with a combination of RYR and coenzyme Q10 showed lipid-lowering activity along with a reduction of inflammatory mediators and an improvement of vascular properties in young subjects with a low-to-moderate CV risk profile.

Coenzyme Q10 inhibits RANKL-induced osteoclastogenesis by regulation of mitochondrial apoptosis and oxidative stress in RAW264.7 cells

Coenzyme Q10 (CoQ10) has been reported to improve bone density and the number of trabeculae in postmenopausal osteoporosis, but the mechanism remains to be elucidated. We aimed to investigate the effects of CoQ10 on receptor activator of NF-κB ligand (RANKL)-induced osteoclastogenesis and the underlying molecular mechanisms. RAW264.7 cells were treated with different concentrations of RANKL to differentiate into osteoclasts, and then these cells were treated with different concentrations of CoQ10 with or without H₂ O₂ . Tartrate-resistant acid phosphatase staining was performed to detect osteoclasts. Cell viability was tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, cell apoptosis was examined by flow cytometry, and the effects of CoQ10 on protein and messenger RNA expression of mitochondrial apoptosis-associated proteins and osteoclast marker proteins were measured by quantitative reverse transcription polymerase chain reaction and western blot, respectively. Furthermore, enzyme-linked immunosorbent assay was conducted to analyze the activities of malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT). RANKL significantly induced osteoclastogenesis in RAW264.7 cells, with the greatest efficiency at 50 ng/ml. CoQ10 had no significant effects on cell viability but it significantly increased the percentages of cell apoptosis. Mechanically, CoQ10 statistically decreased the levels of Bcl-2 and cytochrome C in mitochondria and upregulated the levels of Bax, cleaved caspase 3, and cytochrome C in the cytoplasm. Moreover, CoQ10 significantly decreased RANKL-induced osteoclastogenesis regardless of exposure to H₂ O₂ . In addition, CoQ10 statistically reduced MDA activity and elevated the activities of SOD and CAT, as well as the expression of oxidative stress-related proteins. CoQ10 may inhibit RANKL-induced osteoclastogenesis by regulation of mitochondrial apoptosis and oxidative stress in RAW264.7 cells.

Elevated levels of mitochondrial CoQ10 induce ROS-mediated apoptosis in pancreatic cancer

Reactive oxygen species (ROS) are implicated in triggering cell signalling events and pathways to promote and maintain tumorigenicity. Chemotherapy and radiation can induce ROS to elicit cell death allows for targeting ROS pathways for effective anti-cancer therapeutics. Coenzyme Q10 is a critical cofactor in the electron transport chain with complex biological functions that extend beyond mitochondrial respiration. This study demonstrates that delivery of oxidized Coenzyme Q10 (ubidecarenone) to increase mitochondrial Q-pool is associated with an increase in ROS generation, effectuating anti-cancer effects in a pancreatic cancer model. Consequent activation of cell death was observed in vitro in pancreatic cancer cells, and both human patient-derived organoids and tumour xenografts. The study is a first to demonstrate the effectiveness of oxidized ubidecarenone in targeting mitochondrial function resulting in an anti-cancer effect. Furthermore, these findings support the clinical development of proprietary formulation, BPM31510, for treatment of cancers with high ROS burden with potential sensitivity to ubidecarenone.

Assessing the effectiveness of CoQ10 dietary supplementation on growth performance, digestive enzymes, blood health, immune response, and oxidative-related genes expression of Nile tilapia (Oreochromis niloticus)

The present study was conducted to investigate the effects of CoQ10 dietary supplementation on growth performance, feed utilization, blood profile, immune response, and oxidative status of Nile tilapia (12.4 ± 0.11 g, initial body weight). Five experimental diets were formulated containing CoQ10 at levels of 0, 10, 20, 30, 40 mg kg^-1 diet (D1, D2, D3, D4, and D5, respectively). The results of a 56-days feeding trial showed that, significantly higher weight gain % (WG %), specific growth rate (SGR), feed intake (FI), and feed efficiency ratio (FER) were recorded in fish groups fed diets supplemented with different levels of CoQ10 than fish fed the control diet, while survival rate (SR%), condition factor (CF), hepatosomatic index (HSI) and viscerasomatic index (VSI) showed no obvious differences (P > 0.05) among all experimental groups. The highest activities of digestive enzymes (protease, amylase, and lipase) were recorded in D3, D4, and D5 groups. Moreover, blood status of all experimental fish was within normal rates and significant alterations were only in the case of glucose, cortisol, total cholesterol (T-Chol), triglycerides, and total protein (TP), where fish fed on D3, D4 and D5 diets exhibited lower values of glucose, cortisol, T-Chol, and triglycerides and higher values of TP. Furthermore, the lowest values of immune response [lysozyme, bactericidal, respiratory burst (NBT), and alternative complement pathway activities (ACP)], antioxidant capacity and oxidative related genes expressions [superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GP_X)] resulted from feeding on the basal diet (D1) compared to CoQ10 diets, especially with its high levels {≥20 mg kg^-1 diet (D3, D4, and D5)} in most cases. In conclusion, our results suggest that the use of ≥20 mg CoQ10 kg^-1 diet improves the growth and health being of Nile tilapia.

The Plasma Bioavailability of Coenzyme Q10 Absorbed from the Gut and the Oral Mucosa

Coenzyme Q₁₀ (CoQ₁₀) has a central role in the generation of cellular bioenergy and its regulation. The hydrophobicity exhibited by the CoQ₁₀ molecule leads to reports of poor absorption profiles, therefore, the optimization of formulations and modes of delivery is an ever-evolving therapeutic goal. The aim of this study was to investigate different CoQ₁₀ formulations. The article summarizes the findings from an Australian comparative study involving adults administered CoQ₁₀ through different oral delivery platforms. A total of 11 participants (six males and five females) voluntarily participated in a comparative clinical study of three different CoQ₁₀ formulations across a six-week period, completing 198 person-hours of cumulative contribution equivalent to n = 33 participation. All of the eligible participants (n = 11) administered the three formulations blinded from who the commercial supplier of the formulation was and from what the chemical form of the CoQ₁₀ was that was being administered. The dosing between the CoQ₁₀ preparations were dispensed sequentially and were administered following three-week washouts. Three commercial preparations were tested, which included the following: formulations with capsules each containing ubiquinol and ubiquinone (150 mg/capsule), and a liposome ubiquinone formulation (40 mg/mL at 2 actuations of the pump). A significant inter-subject variation in the plasma level of CoQ₁₀ at baseline that was observed to increase with an increase in age. This trend persisted in the post administration of the different formulations. Furthermore, it was observed that the intestinal absorption and bioavailability of CoQ₁₀ varied significantly in the plasma between subjects, irrespective of whether the ubiquinol or ubiquinone forms were administered. The administration of CoQ₁₀ as a liposome for preparation showed the poorest response in bioavailability. Although the ubiquinol capsule form of CoQ₁₀ was observed to have increased in the plasma versus the ubiquinone capsules and the ubiquinol liposome at the two-hour interval, the inter-subject variation was such that the difference was not significant (p > 0.05). All of the CoQ₁₀ formulations showed no further increases in their plasma levels over the remaining study period (i.e., four hours). This study further concluded that the intestinal absorption of CoQ₁₀ is highly variable and is independent of the molecular form administered. Furthermore, it also concludes that liposomes are not an effective vehicle for the oral administration of CoQ₁₀, and as such, did not improve the oral mucosal/sublingual absorption and bioavailability of the molecule. Of interest was the observation that with the increasing subject age, there was an observed increase in the baseline plasma CoQ₁₀ levels in the participants prior to dosing. It was posited that the increase in the baseline plasma levels of CoQ₁₀ with an increase in age could be due to the loss of skeletal muscle mass, a result that still needs to be verified.

The effects of coenzyme Q10 on oxidative stress and heat shock proteins in rats subjected to acute and chronic exercise

[Purpose]

The aim of the study was to determine the effects of dietary CoQ10 on serum biochemical parameters, lipid peroxidation, and HSP expression in the liver and slow-twitch muscles (soleus and gastronemius deep portion) of exercise-trained rats.

[Methods]

A total of 42 Wistar albino rats were divided into six groups: 1) Control, 2) Coenzyme Q10 (CoQ10), 3) Chronic Exercise (CE), 4) CE + CoQ10, 5) Acute Exercise (AE), and 6) AE + CoQ10. The rats were subjected to the running test 5 days a week for 6 weeks after which CoQ10 was administered via the diet. AE (running on the treadmill until the rats were exhausted) was done on the last day

[Results]

The results showed no significant difference in serum glucose and liver functions in any of the groups. However, CoQ10 and exercise treatment were found to lower cholesterol and triglyceride levels. Serum and muscle malondialdehyde (MDA) levels were found to be lower in the CE and CE + CoQ10 groups compared to the control group. The highest levels of HSP60, HSP70, and HSP90 in liver and muscle were found in the AE group, and the lowest levels were found in CE + CoQ10 group. CoQ10 supplementation reduced HSP expression in both CE-and AE-trained rats (P < 0.05).

[Conclusion]

The results showed that CoQ10 supplementation could reduce MDA levels, protect against oxidative damage, and regulate HSP expression in CE-and AE-trained rats. CE and CoQ10 were shown to reduce oxidative stress synergistically.

Biogerontology: research status, challenges and opportunities

Biogerontology is the study of the biological basis of ageing and age-related diseases. The phenomenon and the process of ageing are well understood in evolutionary and biological terms; and a conceptual framework has been established within which general principles of ageing and longevity can be formulated. The phenotype of ageing in terms of progressive loss of physical function and fitness is best seen during the period of survival after the evolution-determined essential lifespan (ELS) of a species. However, the ageing phenotype is highly heterogenous and individualistic at all levels from the whole body to the molecular one. Most significantly, the process and the progression of ageing are not determined by any specific gerontogenes. Ageing is the result of imperfect maintenance and repair systems that allow a progressive shrinkage of the homeodynamic space of an individual. The challenge is to develop and apply wholistic approaches to the complex trait of ageing for maintaining and/or improving health. One such approach is that of mild stress-induced physiological hormesis by physical, mental and nutritional hormetins. Biogerontological research offers numerous opportunities for developing evidence-based novel biomedical technologies for maintaining and improving health, for preventing the onset of age-related diseases, and for extending the health-span.

Coenzyme Q10 promotes osteoblast proliferation and differentiation and protects against ovariectomy-induced osteoporosis

Coenzyme Q10 (CoQ10) is a fat‑soluble vitamin‑like substance used for the treatment of a variety of disorders, including osteoporosis. The exact mechanism underlying CoQ10‑mediated protection against osteoporosis remains to be elucidated. The present study aimed to evaluate the effect of CoQ10 on osteoblastic cell proliferation and differentiation, and therapeutic effects on a rat model of osteoporosis. Following treatment with different concentrations of CoQ10, cell proliferation and differentiation of rat bone marrow stromal cells (BMSCs), and expression of osteoblastogenic markers, were measured. Rats with osteoporosis subjected to ovariectomy (OVX) were treated with different concentrations of CoQ10. Serum levels of estrogen and bone metabolism markers were measured. Micro computed tomography scans were used to analyze morphological changes in bones. In addition, mRNA and protein levels of phosphatidylinositol 3,4,5‑trisphosphate 3‑phosphatase and dual‑specificity protein phosphatase PTEN (PTEN)/phosphatidylinositol 4,5‑bisphosphate 3‑kinase (PI3K)/RAC‑alpha serine/threonine‑protein kinase(AKT), were determined. CoQ10 significantly increased the proliferation and osteogenic differentiation of BMSCs in a dose‑dependent manner, with an increased expression of osteogenic markers. CoQ10 significantly decreased bone resorption but exhibited no effect on serum E2 levels in vivo. CoQ10 markedly enhanced bone formation. Furthermore, the abundance of p‑PI3K and p‑AKT increased while PTEN levels decreased in a dose‑dependent manner following administration of CoQ10. CoQ10 stimulates the proliferation and differentiation of BMSCs and is effective for the treatment of OVX‑induced osteoporosis in rats. The above effects of CoQ10 may be mediated by activation of the PTEN/PI3K/AKT pathway.

Modulation of mitochondrial dysfunction-related oxidative stress in fibroblasts of patients with Leigh syndrome by inhibition of prooxidative p66Shc pathway

The mitochondrial respiratory chain, and in particular, complex I, is a major source of reactive oxygen species (ROS) in cells. Elevated levels of ROS are associated with an imbalance between the rate of ROS formation and the capacity of the antioxidant defense system. Increased ROS production may lead to oxidation of DNA, lipids and proteins and thus can affect fundamental cellular processes. The aim of this study was to investigate the magnitude of intracellular oxidative stress in fibroblasts of patients with Leigh syndrome with defined mutations in complex I. Moreover, we hypothesized that activation of the p66Shc protein (phosphorylation of p66Shc at Ser36 by PKCβ), being part of the oxidative stress response pathway, is partially responsible for the increased ROS production in cells with dysfunctional complex I. Characterization of bioenergetic parameters and ROS production showed that the cellular model of Leigh syndrome is described by increased intracellular oxidative stress and oxidative damage to DNA and proteins, which correlate with increased p66Shc phosphorylation at Ser36. Treatment of patients' fibroblasts with hispidin (an inhibitor of the protein kinase PKCβ), in addition to decreasing ROS production and intracellular oxidative stress, resulted in restoration of complex I activity.

Coenzyme Q and Its Role in the Dietary Therapy against Aging

Coenzyme Q (CoQ) is a naturally occurring molecule located in the hydrophobic domain of the phospholipid bilayer of all biological membranes. Shortly after being discovered, it was recognized as an essential electron transport chain component in mitochondria where it is particularly abundant. Since then, more additional roles in cell physiology have been reported, including antioxidant, signaling, death prevention, and others. It is known that all cells are able to synthesize functionally sufficient amounts of CoQ under normal physiological conditions. However, CoQ is a molecule found in different dietary sources, which can be taken up and incorporated into biological membranes. It is known that mitochondria have a close relationship with the aging process. Additionally, delaying the aging process through diet has aroused the interest of scientists for many years. These observations have stimulated investigation of the anti-aging potential of CoQ and its possible use in dietary therapies to alleviate the effects of aging. In this context, the present review focus on the current knowledge and evidence the roles of CoQ cells, its relationship with aging, and possible implications of dietary CoQ in relation to aging, lifespan or age-related diseases.

Serum coenzyme Q10 levels as a predictor of dementia in a Japanese general population

Mitochondrial impairment and increased oxidative stress are considered to be involved in the pathogenesis of neurodegenerative diseases, such as Alzheimer's disease. Coenzyme Q10 (CoQ10) is a component of the electron transport chain localized on the inner membrane of the mitochondria. In addition to its bioenergetic activity required for ATP synthesis, CoQ10 also has antioxidant activity in mitochondrial and lipid membranes, which protects against the reactive oxidative species generated during oxidative phosphorylation. Several previous studies had reported no significant differences in serum CoQ10 levels between patients with and without dementia, such as Alzheimer's disease. However, in this issue of Atherosclerosis, Yamagishi et al. demonstrate for the first time that a lower serum CoQ10 level is associated with a greater risk of dementia in a Japanese general population. These findings suggest that assessing serum CoQ10 levels could be useful for predicting the development of dementia, rather than as a biomarker for the presence of dementia.

Coenzyme Q10 treatments influence the lifespan and key biochemical resistance systems in the honeybee, Apis mellifera

Natural bioactive preparations that will boost apian resistance, aid body detoxification, or fight crucial bee diseases are in demand. Therefore, we examined the influence of coenzyme Q10 (CoQ10, 2,3-dimethoxy, 5-methyl, 6-decaprenyl benzoquinone) treatment on honeybee lifespan, Nosema resistance, the activity/concentration of antioxidants, proteases and protease inhibitors, and biomarkers. CoQ10 slows age-related metabolic processes. Workers that consumed CoQ10 lived longer than untreated controls and were less infested with Nosema spp. Relative to controls, the CoQ10-treated workers had higher protein concentrations that increased with age but then they decreased in older bees. CoQ10 treatments increased the activities of antioxidant enzymes (superoxide dismutase, GPx, catalase, glutathione S-transferase), protease inhibitors, biomarkers (aspartate aminotransferase, alkaline phosphatase, alanine aminotransferase), the total antioxidant potential level, and concentrations of uric acid and creatinine. The activities of acidic, neutral, and alkaline proteases, and concentrations of albumin and urea were lower in the bees that were administered CoQ10. CoQ10 could be taken into consideration as a natural diet supplement in early spring before pollen sources become available in the temperate Central European climate. A response to CoQ10 administration that is similar to mammals supports our view that Apis mellifera is a model organism for biochemical gerontology.

Ginger (Zingiber officinale) and chemotherapy-induced nausea and vomiting: a systematic literature review

Chemotherapy-induced nausea and vomiting (CINV) is a common side-effect of cytotoxic treatment. It continues to affect a significant proportion of patients despite the widespread use of antiemetic medication. In traditional medicine, ginger (Zingiber officinale) has been used to prevent and treat nausea in many cultures for thousands of years. However, its use has not been confirmed in the chemotherapy context. To determine the potential use of ginger as a prophylactic or treatment for CINV, a systematic literature review was conducted. Reviewed studies comprised randomized controlled trials or crossover trials that investigated the anti-CINV effect of ginger as the sole independent variable in chemotherapy patients. Seven studies met the inclusion criteria. All studies were assessed on methodological quality and their limitations were identified. Studies were mixed in their support of ginger as an anti-CINV treatment in patients receiving chemotherapy, with three demonstrating a positive effect, two in favor but with caveats, and two showing no effect on measures of CINV. Future studies are required to address the limitations identified before clinical use can be recommended.

Argan Oil-contained Antioxidants for Human Mitochondria

The powerful antioxidant capacity of virgin argan oil is attributed to its content of antioxidant molecules. Recent investigations have identified CoQ10 and melatonin as some of these antioxidant molecules. In this review, we summarize the most recent data about the content of CoQ10 and melatonin in virgin argan oil and the differences found in samples extracted by the traditional and half-industrialized methods. We also emphasize the importance of these two molecules for human health, focusing on their actions in mitochondria. Finally, we refer to other abundant antioxidants in virgin argan oil: tocopherols and polyphenols.

Effect of coenzyme-q10 on Doxorubicin-induced nephrotoxicity in rats

Nephrotoxicity is one of the limiting factors for using doxorubicin (Dox) as an anticancer chemotherapeutic. Here, we investigated possible protective effect of coenzyme-Q10 (CoQ10) on Dox-induced nephrotoxicity and the mechanisms involved. Two doses (10 and 100 mg/kg) of CoQ10 were administered orally to rats for 8 days, in the presence or absence of nephrotoxicity induced by a single intraperitoneal injection of Dox (15 mg/kg) at day 4 of the experiment. Our results showed that the low dose of CoQ10 succeeded in reversing Dox-induced nephrotoxicity to control levels (e.g., levels of blood urea nitrogen and serum creatinine, concentrations of renal reduced glutathione (GSH) and malondialdehyde, catalase activity and caspase 3 expression, and renal histopathology). Alternatively, the high dose of CoQ10 showed no superior nephroprotection over the low dose, as there were no significant improvements in renal histopathology, catalase activity, or caspase 3 expression compared to the Dox-treated group. Interestingly, the high dose of CoQ10 alone significantly decreased renal GSH level as well as catalase activity and caused a mild induction of caspase 3 expression compared to control, probably due to a prooxidant effect at this dose of CoQ10. We conclude that CoQ10 protects from Dox-induced nephrotoxicity with a precaution to dosage adjustment.

Behavioral improvement after chronic administration of coenzyme Q10 in P301S transgenic mice

Coenzyme Q10 is a key component of the electron transport chain which plays an essential role in ATP production and also has antioxidant effects. Neuroprotective effects of coenzyme Q10 have been reported in both in vitro and in vivo models of neurodegenerative diseases. However, its effects have not been studied in cells or in animals with tau induced pathology. In this report, we administered coenzyme Q10 to transgenic mice with the P301S tau mutation, which causes fronto-temporal dementia in man. These mice develop tau hyperphosphorylation and neurofibrillary tangles in the brain. Coenzyme Q10 improved survival and behavioral deficits in the P301S mice. There was a modest reduction in phosphorylated tau in the cortex of P301S mice. We also examined the effects of coenzyme Q10 treatment on the electron transport chain enzymes, the mitochondrial antioxidant enzymes, and the tricarboxylic acid cycle. There was a significant increase in complex I activity and protein levels, and a reduction in lipid peroxidation. Our data show that coenzyme Q10 significantly improved behavioral deficits and survival in transgenic mice with the P301S tau mutation, upregulated key enzymes of the electron transport chain, and reduced oxidative stress.

The Redox System in C. elegans, a Phylogenetic Approach

Oxidative stress is a toxic state caused by an imbalance between the production and elimination of reactive oxygen species (ROS). ROS cause oxidative damage to cellular components such as proteins, lipids, and nucleic acids. While the role of ROS in cellular damage is frequently all that is noted, ROS are also important in redox signalling. The "Redox Hypothesis" has been proposed to emphasize a dual role of ROS. This hypothesis suggests that the primary effect of changes to the redox state is modified cellular signalling rather than simply oxidative damage. In extreme cases, alteration of redox signalling can contribute to the toxicity of ROS, as well as to ageing and age-related diseases. The nematode species Caenorhabditis elegans provides an excellent model for the study of oxidative stress and redox signalling in animals. We use protein sequences from central redox systems in Homo sapiens, Drosophila melanogaster, and Saccharomyces cerevisiae to query Genbank for homologous proteins in C. elegans. We then use maximum likelihood phylogenetic analysis to compare protein families between C. elegans and the other organisms to facilitate future research into the genetics of redox biology.

Oxidative stress in surgery in an ageing population: pathophysiology and therapy

Reactive oxygen species (ROS) play an important role in the regulation of normal cellular function. When ROS are produced in excess they can have detrimental effects, a state known as oxidative stress. Thus ROS play both physiological and pathophysiological roles in the body. In clinical practice oxidative stress and its counterpart, antioxidant capacity can be measured and can guide remedial therapy. Oxidative stress can have a negative impact in all forms of major surgery including cardiac surgery, general surgery, trauma surgery, orthopedic surgery and plastic surgery; this is particularly marked in an ageing population. Many different therapies to reduce oxidative stress in surgery have been tried with variable results. We conclude that in surgical patients the assessment of oxidative stress, improvement of the understanding of its role, both positive and negative, and devising appropriate therapies represent fruitful fields for future research.

A modern approach to the treatment of mitochondrial disease

The treatment of mitochondrial disease varies considerably. Most experts use a combination of vitamins, optimize patients' nutrition and general health, and prevent worsening of symptoms during times of illness and physiologic stress. We agree with this approach, and we agree that therapies using vitamins and cofactors have value, though there is debate about the choice of these agents and the doses prescribed. Despite the paucity of high-quality scientific evidence, these therapies are relatively harmless, may alleviate select clinical symptoms, and theoretically may offer a means of staving off disease progression. Like many other mitochondrial medicine physicians, we have observed significant (and at times life-altering) clinical responses to such pharmacologic interventions. However, it is not yet proven that these therapies truly alter the course of the disease, and some experts may choose not to use these medications at all. At present, the evidence of their effectiveness does not rise to the level required for universal use. Based on our clinical experience and judgment, however, we agree that a therapeutic trial of coenzyme Q10, along with other antioxidants, should be attempted. Although individual specialists differ as to the exact drug cocktail, a common approach involves combinations of antioxidants that may have a synergistic effect. Because almost all relevant therapies are classified as medical foods or over-the-counter supplements, most physicians also attempt to balance the apparent clinical benefit of mitochondrial cocktails with the cost burden that these supplements pose for the family.

Probucol ameliorates renal and metabolic sequelae of primary CoQ deficiency in Pdss2 mutant mice

Therapy of mitochondrial respiratory chain diseases is complicated by limited understanding of cellular mechanisms that cause the widely variable clinical findings. Here, we show that focal segmental glomerulopathy-like kidney disease in Pdss2 mutant animals with primary coenzyme Q (CoQ) deficiency is significantly ameliorated by oral treatment with probucol (1% w/w). Preventative effects in missense mutant mice are similar whether fed probucol from weaning or for 3 weeks prior to typical nephritis onset. Furthermore, treating symptomatic animals for 2 weeks with probucol significantly reduces albuminuria. Probucol has a more pronounced health benefit than high-dose CoQ₁₀ supplementation and uniquely restores CoQ₉ content in mutant kidney. Probucol substantially mitigates transcriptional alterations across many intermediary metabolic domains, including peroxisome proliferator-activated receptor (PPAR) pathway signaling. Probucol's beneficial effects on the renal and metabolic manifestations of Pdss2 disease occur despite modest induction of oxidant stress and appear independent of its hypolipidemic effects. Rather, decreased CoQ₉ content and altered PPAR pathway signaling appear, respectively, to orchestrate the glomerular and global metabolic consequences of primary CoQ deficiency, which are both preventable and treatable with oral probucol therapy.

Exogenous coenzyme Q10 modulates MMP-2 activity in MCF-7 cell line as a breast cancer cellular model

Background/Aims

Matrix Metalloproteinases 2 is a key molecule in cellular invasion and metastasis. Mitochondrial ROS has been established as a mediator of MMP activity. Coenzyme Q₁₀ contributes to intracellular ROS regulation. Coenzyme Q₁₀ beneficial effects on cancer are still in controversy but there are indications of Coenzyme Q₁₀ complementing effect on tamoxifen receiving breast cancer patients.

Methods

In this study we aimed to investigate the correlation of the effects of co-incubation of coenzyme Q10 and N-acetyl-L-cysteine (NAC) on intracellular H2O2 content and Matrix Metalloproteinase 2 (MMP-2) activity in MCF-7 cell line.

Results and Discussion

Our experiment was designed to assess the effect in a time and dose related manner. Gelatin zymography and Flowcytometric measurement of H2O2 by 2'7',-dichlorofluorescin-diacetate probe were employed. The results showed that both coenzyme Q10 and N-acetyl-L-cysteine reduce MMP-2 activity along with the pro-oxidant capacity of the MCF-7 cell in a dose proportionate manner.

Conclusions

Collectively, the present study highlights the significance of Coenzyme Q₁₀ effect on the cell invasion/metastasis effecter molecules.

A randomized trial of coenzyme Q10 in mitochondrial disorders

Case reports and open-label studies suggest that coenzyme Q(10) (CoQ(10)) treatment may have beneficial effects in mitochondrial disease patients; however, controlled trials are warranted to clinically prove its effectiveness. Thirty patients with mitochondrial cytopathy received 1200 mg/day CoQ(10) for 60 days in a randomized, double-blind, cross-over trial. Blood lactate, urinary markers of oxidative stress, body composition, activities of daily living, quality of life, forearm handgrip strength and oxygen desaturation, cycle exercise cardiorespiratory variables, and brain metabolites were measured. CoQ(10) treatment attenuated the rise in lactate after cycle ergometry, increased (∽1.93 ml) VO(2)/kg lean mass after 5 minutes of cycling (P < 0.005), and decreased gray matter choline-containing compounds (P < 0.05). Sixty days of moderate- to high-dose CoQ(10) treatment had minor effects on cycle exercise aerobic capacity and post-exercise lactate but did not affect other clinically relevant variables such as strength or resting lactate.

Neurodevelopmental manifestations of mitochondrial disease

Mitochondrial disease is an increasingly recognized but widely heterogeneous group of multisystemic disorders that commonly involve severe neurodevelopmental manifestations in childhood. This review explores the presentation, genetic basis, and diagnostic evaluation of primary mitochondrial disease. Emphasis is placed on neurodevelopmental findings that may be encountered by a Developmental Pediatrician that should provoke consideration of a mitochondrial disorder. The inheritance patterns and mechanisms by which mutations in genes located in either the nuclear or mitochondrial genomes can cause mitochondrial diseases are discussed. A general overview of the current diagnostic evaluation that can be readily initiated by the Developmental Pediatrician is provided, along with a summary of currently available treatment options.