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Moon Hee Jeong, Jin Hwan Kim, Kang-Sik Seo, Tae Hwan Kwak, Woo Jin Park
Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is a mitochondrial disease caused by mutations in the mitochondrial genome. This study investigated the efficacy of β-lapachone (β-lap), a natural quinone compound, in rescuing mitochondrial dysfunction in MELAS cybrid cells. β-Lap significantly restored energy production and mitochondrial membrane potential as well as normalized the elevated ROS level in MELAS cybrid cells. Additionally, β-lap reduced lactic acidosis and restored glucose uptake in the MELAS cybrid cells...
November 21, 2014: Biochemical and Biophysical Research Communications
Jesús Castro-Marrero, Mario D Cordero, María José Segundo, Naia Sáez-Francàs, Natalia Calvo, Lourdes Román-Malo, Luisa Aliste, Tomás Fernández de Sevilla, José Alegre
Chronic fatigue syndrome (CFS) is a chronic and extremely debilitating illness characterized by prolonged fatigue and multiple symptoms with unknown cause, diagnostic test, or universally effective treatment. Inflammation, oxidative stress, mitochondrial dysfunction, and CoQ10 deficiency have been well documented in CFS. We conducted an 8-week, randomized, double-blind placebo-controlled trial to evaluate the benefits of oral CoQ10 (200 mg/day) plus NADH (20 mg/day) supplementation on fatigue and biochemical parameters in 73 Spanish CFS patients...
March 10, 2015: Antioxidants & Redox Signaling
Garth L Nicolson
Loss of function in mitochondria, the key organelle responsible for cellular energy production, can result in the excess fatigue and other symptoms that are common complaints in almost every chronic disease. At the molecular level, a reduction in mitochondrial function occurs as a result of the following changes: (1) a loss of maintenance of the electrical and chemical transmembrane potential of the inner mitochondrial membrane, (2) alterations in the function of the electron transport chain, or (3) a reduction in the transport of critical metabolites into mitochondria...
2014: Alternative Therapies in Health and Medicine
G López-Lluch, M Rios, M A Lane, P Navas, R de Cabo
Caloric restriction (CR) is known as the only non-genetic method proven to slow the rate of aging and extend lifespan in animals. Free radicals production emerges from normal metabolic activity and generates the accumulation of oxidized macromolecules, one of the main characteristics of aging. Due to its central role in cell bioenergetics, a great interest has been paid to CR-induced modifications in mitochondria, where CR has been suggested to decrease reactive oxygen species production. The plasma membrane contains a trans-membrane redox system (PMRS) that provides electrons to recycle lipophilic antioxidants, such as α-tocopherol and coenzyme Q (CoQ), and to modulate cytosolic redox homeostasis...
June 2005: Age (2005-)
Fernando Gomes, Erich B Tahara, Cleverson Busso, Alicia J Kowaltowski, Mario H Barros
Saccharomyces cerevisiae has three distinct inner mitochondrial membrane NADH dehydrogenases mediating the transfer of electrons from NADH to CoQ (coenzyme Q): Nde1p, Nde2p and Ndi1p. The active site of Ndi1p faces the matrix side, whereas the enzymatic activities of Nde1p and Nde2p are restricted to the intermembrane space side, where they are responsible for cytosolic NADH oxidation. In the present study we genetically manipulated yeast strains in order to alter the redox state of CoQ and NADH dehydrogenases to evaluate the consequences on mtDNA (mitochondrial DNA) maintenance...
February 1, 2013: Biochemical Journal
Nina Mikirova, Joseph Casciari, Ronald Hunninghake
CONTEXT: Chronic fatigue syndrome (CFS) is a debilitating fatigue illness that has unknown etiology and lacks an objective diagnostic marker. OBJECTIVE: To examine the metabolic component of CFS to determine if practitioners can use serum NAD(P)H concentration measurements to monitor metabolism and fatigue status in patients with CFS. DESIGN: The research team conducted a case-control study, comparing a group of patients who were diagnosed with CFS with a control group of healthy subjects...
January 2012: Alternative Therapies in Health and Medicine
Roman H Haefeli, Michael Erb, Anja C Gemperli, Dimitri Robay, Isabelle Courdier Fruh, Corinne Anklin, Robert Dallmann, Nuri Gueven
Short-chain quinones are described as potent antioxidants and in the case of idebenone have already been under clinical investigation for the treatment of neuromuscular disorders. Due to their analogy to coenzyme Q10 (CoQ10), a long-chain quinone, they are widely regarded as a substitute for CoQ10. However, apart from their antioxidant function, this provides no clear rationale for their use in disorders with normal CoQ10 levels. Using recombinant NAD(P)H:quinone oxidoreductase (NQO) enzymes, we observed that contrary to CoQ10 short-chain quinones such as idebenone are good substrates for both NQO1 and NQO2...
2011: PloS One
Francesca Bruge, Samantha Virgili, Tiziana Cacciamani, Federica Principi, Luca Tiano, Gian Paolo Littarru
Two-electron reduction of quinones catalyzed by NAD(P)H:quinone oxidoreductase (NQO1) protects cells against oxidative stress and toxic quinones. In fact, low level of NQO1 activity is often associated with increased risk of developing different types of tumours and with toxic effects linked to environmental quinones. In a previous report we analyzed the relationship between the oxidative stress induced by UV radiation and CoQ10 content in Burkitt's lymphoma cell lines compared to HL-60. The basal content of CoQ10 in Raji cells was slightly higher compared to HL-60...
2008: BioFactors
Mario H Barros, Alisha Johnson, Peter Gin, Beth N Marbois, Catherine F Clarke, Alexander Tzagoloff
Deletion of the Saccharomyces cerevisiae gene YOL008W, here referred to as COQ10, elicits a respiratory defect as a result of the inability of the mutant to oxidize NADH and succinate. Both activities are restored by exogenous coenzyme Q2. Respiration is also partially rescued by COQ2, COQ7, or COQ8/ABC1, when these genes are present in high copy. Unlike other coq mutants, all of which lack Q6, the coq10 mutant has near normal amounts of Q6 in mitochondria. Coq10p is widely distributed in bacteria and eukaryotes and is homologous to proteins of the "aromatic-rich protein family" Pfam03654 and to members of the START domain superfamily that have a hydrophobic tunnel implicated in binding lipophilic molecules such as cholesterol and polyketides...
December 30, 2005: Journal of Biological Chemistry
Rosario I Bello, Consuelo Gómez-Díaz, María I Burón, Francisco J Alcaín, Plácido Navas, José M Villalba
Coenzyme Q10 supplementation increases life-span of rats fed on a diet enriched with polyunsaturated fatty acids (Quiles, J.L., Ochoa, J.J., Huertas, J.R., Mataix, J., 2004b. Coenzyme Q supplementation protects from age-related DNA double-strand breaks and increased lifespan in rats fed on a PUFA-rich diet. Exp. Gerontol. 39, 189-194). Our study was set as a first attempt to establish a mechanistic link between life span extension and CoQ10 supplementation. When rats were fed on a PUFAn-6 plus CoQ10 diet, levels of CoQ10 were increased in plasma membrane at every time point compared to control rats fed on a PUFAn-6-alone diet...
August 2005: Experimental Gerontology
Milena Merlo Pich, Alida Castagnoli, Annalisa Biondi, Andrea Bernacchia, Pier Luigi Tazzari, Marilena D'Aurelio, Giovanna Parenti Castelli, Gabriella Formiggini, Roberto Conte, Carla Bovina, Giorgio Lenaz
The conditions under which Coenzyme Q (CoQ) may protect platelet mitochondrial function of transfusional buffy coats from aging and from induced oxidative stress were investigated. The Pasteur effect, i.e. the enhancement of lactate production after inhibition of mitochondrial respiratory chain, was exploited as a marker of mitochondrial function as it allows to calculate the ratio of mitochondrial ATP to glycolytic ATP. Reduced CoQ10 improves platelet mitochondrial function of transfusional buffy coats and protects the cells from induced oxidative stress...
April 2002: Free Radical Research
A Arroyo, V E Kagan, V A Tyurin, J R Burgess, R de Cabo, P Navas, J M Villalba
High affinity for NADH, and low affinity for NADPH, for reduction of endogenous coenzyme Q10 (CoQ10) by pig liver plasma membrane is reported in the present work. CoQ reduction in plasma membrane is carried out, in addition to other mechanisms, by plasma membrane coenzyme Q reductase (PMQR). We show that PMQR-catalyzed reduction of CoQ0 by both NADH and NADPH is accompanied by generation of CoQ0 semiquinone radicals in a superoxide-dependent reaction. In the presence of a water-soluble vitamin E homologue, Trolox, this reduction leads to quenching of the Trolox phenoxyl radicals...
2000: Antioxidants & Redox Signaling
A Gvozdjáková, J Kucharská, S Mizera, Z Braunová, Z Schreinerová, E Schrameková, I Pechán, J Fabián
UNLABELLED: Sixty endomyocardial biopsies (EMB) and whole blood or plasma samples from 34 patients after heart transplantation (HTx-pts) were studied. Acute rejection of the transplanted heart was histologically graded as: 0 (without), 0-1 (incipient), 1 (mild), 2 (moderate). The level of coenzyme Q10 (CoQ10) in 28 EMB was estimated by HPLC. Mitochondrial respiratory chain function and energy production were measured in 60 EMB. This study is the first report showing a correlation between: (a) histological signs of rejection in the human transplanted heart and (b) CoQ10 level of EMB, CoQ10 blood level, and mitochondrial bioenergetic processes: inhibition in FAD-part, but not in NAD-part of respiratory chain...
1999: BioFactors
C W Shults, M F Beal, D Fontaine, K Nakano, R H Haas
We report a pilot study of three oral doses of coenzyme Q10 (CoQ10) (200 mg administered two, three, or four times per day for 1 month) in 15 subjects with Parkinson's disease. Oral CoQ10 caused a substantial increase in the plasma CoQ10 level. It was well tolerated, but at the highest dose (200 mg four times per day) mild, transient changes in the urine were noted. CoQ10 did not change the mean score on the motor portion of the Unified Parkinson's Disease Rating Scale. There was a trend toward an increase in complex I activity in the subjects...
March 1998: Neurology
R E Beyer, J Segura-Aguilar, S di Bernardo, M Cavazzoni, R Fato, D Fiorentini, M C Galli, M Setti, L Landi, G Lenaz
The experiments reported here were undertaken to test the hypothesis that the antioxidative, reduced form of hydrophobic phase coenzyme Q (CoQ) may be generated and maintained by the two-electron quinone reductase, DT-diaphorase [NAD(P)H:(quinone-acceptor) oxidoreductase, EC] by catalyzing formation of the hydroquinone form of CoQ. This enzyme was isolated and purified from rat liver cytosol and its reduction of several CoQ homologs incorporated into large unilamellar vesicles (LUVETs) was demonstrated...
1997: Molecular Aspects of Medicine
C Gómez-Díaz, J M Villalba, R Pérez-Vicente, F L Crane, P Navas
Long-term treatment with ethidium bromide of HL-60 cells induced a mitochondria-deficient rho degree cell line, where mitochondrial DNA can not be identified by PCR and cytochrome c oxidase activity was 80% decreased. These cells showed a progressive increase of ascorbate stabilization which was 52% higher in the established rho degree HL-60 cells. Both CoQ10 and NADH-ascorbate free radical reductase of the plasma membrane were increased in rho(0)HL-60 cells compared to parental cells, while NADH-cytochrome c reductase was unchanged...
May 8, 1997: Biochemical and Biophysical Research Communications
R E Beyer, J Segura-Aguilar, S Di Bernardo, M Cavazzoni, R Fato, D Fiorentini, M C Galli, M Setti, L Landi, G Lenaz
The experiments reported here were designed to test the hypothesis that the two-electron quinone reductase DT-diaphorase [NAD(P)H:(quinone-acceptor) oxidoreductase, EC] functions to maintain membrane-bound coenzyme Q (CoQ) in its reduced antioxidant state, thereby providing protection from free radical damage. DT-diaphorase was isolated and purified from rat liver cytosol, and its ability to reduce several CoQ homologs incorporated into large unilamellar vesicles was demonstrated. Addition of NADH and DT-diaphorase to either large unilamellar or multilamellar vesicles containing homologs of CoQ, including CoQ9 and CoQ10, resulted in the essentially complete reduction of the CoQ...
March 19, 1996: Proceedings of the National Academy of Sciences of the United States of America
R Fato, E Estornell, S Di Bernardo, F Pallotti, G Parenti Castelli, G Lenaz
The reduction kinetics of coenzyme Q (CoQ, ubiquinone) by NADH:ubiquinone oxidoreductase (complex I, EC was investigated in bovine heart mitochondrial membranes using water-soluble homologs and analogs of the endogenous ubiquinone acceptor CoQ10 [the lower homologs from CoQ0 to CoQ3, the 6-pentyl (PB) and 6-decyl (DB) analogs, and duroquinone]. By far the best substrates in bovine heart submitochondrial particles are CoQ1 and PB. The kinetics of NADH-CoQ reductase was investigated in detail using CoQ1 and PB as acceptors...
February 27, 1996: Biochemistry
M L Genova, C Bovina, G Formiggini, V Ottani, S Sassi, M Marchetti
The system of perfusing rat livers has been used to evaluate the uptake and incorporation of liposomal CoQ10 into mitochondria. After 90 minutes of perfusion the cells are strongly enriched in CoQ10 up to levels of the same order of magnitude as CoQ9. Heavy and light mitochondrial crude subcellular fractions, low in CoQ10 in control livers, contain high amounts of the quinone after perfusion; yet the purification of these fractions on a metrizamide gradient reveals that the exogenous quinone is mainly associated with the light mitochondrial subfraction, enriched in lysosomes...
1994: Molecular Aspects of Medicine
G Lenaz, R Fato, C Castelluccio, M Cavazzoni, E Estornell, J F Huertas, F Pallotti, G Parenti Castelli, H Rauchova
The apparent Km for coenzyme Q10 in NADH oxidation by coenzyme Q (CoQ)-extracted beef heart mitochondria is close to their CoQ content, whereas both succinate and glycerol-3-phosphate oxidation (the latter measured in hamster brown adipose tissue mitochondria) are almost saturated at physiological CoQ concentration. Attempts to enhance NADH oxidation rate by excess CoQ incorporation in vitro were only partially successful: the reason is in the limited amount of CoQ10 that can be incorporated in monomeric form, as shown by lack of fluorescence quenching of membrane fluorescent probes; at difference with CoQ10, CoQ5 quenches probe fluorescence and likewise enhances NADH oxidation rate above normal...
1994: Molecular Aspects of Medicine
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