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NMR Spectroscopy Identifies Chemicals in Cigarette Smoke Condensate That Impair Skeletal Muscle Mitochondrial Function. TOXICS 2022; 10:toxics10030140. [PMID: 35324765 PMCID: PMC8955362 DOI: 10.3390/toxics10030140] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/01/2022] [Accepted: 03/11/2022] [Indexed: 01/16/2023]
Abstract
Tobacco smoke-related diseases such as chronic obstructive pulmonary disease (COPD) are associated with high healthcare burden and mortality rates. Many COPD patients were reported to have muscle atrophy and weakness, with several studies suggesting intrinsic muscle mitochondrial impairment as a possible driver of this phenotype. Whereas much information has been learned about muscle pathology once a patient has COPD, little is known about how active tobacco smoking might impact skeletal muscle physiology or mitochondrial health. In this study, we examined the acute effects of cigarette smoke condensate (CSC) on muscle mitochondrial function and hypothesized that toxic chemicals present in CSC would impair mitochondrial respiratory function. Consistent with this hypothesis, we found that acute exposure of muscle mitochondria to CSC caused a dose-dependent decrease in skeletal muscle mitochondrial respiratory capacity. Next, we applied an analytical nuclear magnetic resonance (NMR)-based approach to identify 49 water-soluble and 12 lipid-soluble chemicals with high abundance in CSC. By using a chemical screening approach in the Seahorse XF96 analyzer, several CSC-chemicals, including nicotine, o-Cresol, phenylacetate, and decanoic acid, were found to impair ADP-stimulated respiration in murine muscle mitochondrial isolates significantly. Further to this, several chemicals, including nicotine, o-Cresol, quinoline, propylene glycol, myo-inositol, nitrosodimethylamine, niacinamide, decanoic acid, acrylonitrile, 2-naphthylamine, and arsenic acid, were found to significantly decrease the acceptor control ratio, an index of mitochondrial coupling efficiency.
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Lai N, Fealy CE, Kummitha CM, Cabras S, Kirwan JP, Hoppel CL. Mitochondrial Utilization of Competing Fuels Is Altered in Insulin Resistant Skeletal Muscle of Non-obese Rats (Goto-Kakizaki). Front Physiol 2020; 11:677. [PMID: 32612543 PMCID: PMC7308651 DOI: 10.3389/fphys.2020.00677] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 05/26/2020] [Indexed: 12/25/2022] Open
Abstract
Aim Insulin-resistant skeletal muscle is characterized by metabolic inflexibility with associated alterations in substrate selection, mediated by peroxisome-proliferator activated receptor δ (PPARδ). Although it is established that PPARδ contributes to the alteration of energy metabolism, it is not clear whether it plays a role in mitochondrial fuel competition. While nutrient overload may impair metabolic flexibility by fuel congestion within mitochondria, in absence of obesity defects at a mitochondrial level have not yet been excluded. We sought to determine whether reduced PPARδ content in insulin-resistant rat skeletal muscle of a non-obese rat model of T2DM (Goto-Kakizaki, GK) ameliorate the inhibitory effect of fatty acid (i.e., palmitoylcarnitine) on mitochondrial carbohydrate oxidization (i.e., pyruvate) in muscle fibers. Methods Bioenergetic function was characterized in oxidative soleus (S) and glycolytic white gastrocnemius (WG) muscles with measurement of respiration rates in permeabilized fibers in the presence of complex I, II, IV, and fatty acid substrates. Mitochondrial content was measured by citrate synthase (CS) and succinate dehydrogenase activity (SDH). Western blot was used to determine protein expression of PPARδ, PDK isoform 2 and 4. Results CS and SDH activity, key markers of mitochondrial content, were reduced by ∼10-30% in diabetic vs. control, and the effect was evident in both oxidative and glycolytic muscles. PPARδ (p < 0.01), PDK2 (p < 0.01), and PDK4 (p = 0.06) protein content was reduced in GK animals compared to Wistar rats (N = 6 per group). Ex vivo respiration rates in permeabilized muscle fibers determined in the presence of complex I, II, IV, and fatty acid substrates, suggested unaltered mitochondrial bioenergetic function in T2DM muscle. Respiration in the presence of pyruvate was higher compared to palmitoylcarnitine in both animal groups and fiber types. Moreover, respiration rates in the presence of both palmitoylcarnitine and pyruvate were reduced by 25 ± 6% (S), 37 ± 6% (WG) and 63 ± 6% (S), 57 ± 8% (WG) compared to pyruvate for both controls and GK, respectively. The inhibitory effect of palmitoylcarnitine on respiration was significantly greater in GK than controls (p < 10-3). Conclusion With competing fuels, the presence of fatty acids diminishes mitochondria ability to utilize carbohydrate derived substrates in insulin-resistant muscle despite reduced PPARδ content.
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Affiliation(s)
- Nicola Lai
- Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, VA, United States.,Biomedical Engineering Institute, Old Dominion University, Norfolk, VA, United States.,Department of Mechanical, Chemical and Materials Engineering, University of Cagliari, Cagliari, Italy.,Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States.,Center for Mitochondrial Disease, Case Western Reserve University, Cleveland, OH, United States
| | - Ciarán E Fealy
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States
| | - Chinna M Kummitha
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
| | - Silvia Cabras
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
| | - John P Kirwan
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States.,Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH, United States.,Pennington Biomedical Research Center, Baton Rouge, LA, United States
| | - Charles L Hoppel
- Center for Mitochondrial Disease, Case Western Reserve University, Cleveland, OH, United States.,Department of Pharmacology, Case Western Reserve University, Cleveland, OH, United States.,Department of Medicine, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
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Galkin A, Moncada S. Modulation of the conformational state of mitochondrial complex I as a target for therapeutic intervention. Interface Focus 2017; 7:20160104. [PMID: 28382200 DOI: 10.1098/rsfs.2016.0104] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
In recent years, there have been significant advances in our understanding of the functions of mitochondrial complex I other than the generation of energy. These include its role in generation of reactive oxygen species, involvement in the hypoxic tissue response and its possible regulation by nitric oxide (NO) metabolites. In this review, we will focus on the hypoxic conformational change of this mitochondrial enzyme, the so-called active/deactive transition. This conformational change is physiological and relevant to the understanding of certain pathological conditions including, in the cardiovascular system, ischaemia/reperfusion (I/R) damage. We will discuss how complex I can be affected by NO metabolites and will outline some potential mitochondria-targeted therapies in I/R damage.
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Affiliation(s)
- Alexander Galkin
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, 401 East 61st Street, 5th floor, New York, NY 10065, USA; Queens University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Salvador Moncada
- Manchester Cancer Research Centre , University of Manchester , Wilmslow Road, Manchester M20 4QL , UK
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Dröse S, Stepanova A, Galkin A. Ischemic A/D transition of mitochondrial complex I and its role in ROS generation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:946-57. [PMID: 26777588 PMCID: PMC4893024 DOI: 10.1016/j.bbabio.2015.12.013] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 12/11/2015] [Accepted: 12/25/2015] [Indexed: 12/12/2022]
Abstract
Mitochondrial complex I (NADH:ubiquinone oxidoreductase) is a key enzyme in cellular energy metabolism and provides approximately 40% of the proton-motive force that is utilized during mitochondrial ATP production. The dysregulation of complex I function – either genetically, pharmacologically, or metabolically induced – has severe pathophysiological consequences that often involve an imbalance in the production of reactive oxygen species (ROS). Slow transition of the active (A) enzyme to the deactive, dormant (D) form takes place during ischemia in metabolically active organs such as the heart and brain. The reactivation of complex I occurs upon reoxygenation of ischemic tissue, a process that is usually accompanied by an increase in cellular ROS production. Complex I in the D-form serves as a protective mechanism preventing the oxidative burst upon reperfusion. Conversely, however, the D-form is more vulnerable to oxidative/nitrosative damage. Understanding the so-called active/deactive (A/D) transition may contribute to the development of new therapeutic interventions for conditions like stroke, cardiac infarction, and other ischemia-associated pathologies. In this review, we summarize current knowledge on the mechanism of A/D transition of mitochondrial complex I considering recently available structural data and site-specific labeling experiments. In addition, this review discusses in detail the impact of the A/D transition on ROS production by complex I and the S-nitrosation of a critical cysteine residue of subunit ND3 as a strategy to prevent oxidative damage and tissue damage during ischemia–reperfusion injury. This article is part of a Special Issue entitled Respiratory complex I, edited by Volker Zickermann and Ulrich Brandt. The current knowledge on active/deactive (A/D) transition of complex I is reviewed. The mechanism and driving force of the A/D conformational change are discussed. The A/D transition can affect ROS production and ischemia/reperfusion injury.
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Affiliation(s)
- Stefan Dröse
- Clinic of Anesthesiology, Intensive-Care Medicine and Pain Therapy, University Hospital Frankfurt, Frankfurt am Main 60590, Germany.
| | - Anna Stepanova
- Medical Biology Centre, School of Biological Sciences, Queens University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Alexander Galkin
- Medical Biology Centre, School of Biological Sciences, Queens University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK; Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, 407 East 61st Street, New York, NY 10065, USA.
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Babot M, Birch A, Labarbuta P, Galkin A. Characterisation of the active/de-active transition of mitochondrial complex I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:1083-92. [PMID: 24569053 PMCID: PMC4331042 DOI: 10.1016/j.bbabio.2014.02.018] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Revised: 02/14/2014] [Accepted: 02/17/2014] [Indexed: 12/12/2022]
Abstract
Oxidation of NADH in the mitochondrial matrix of aerobic cells is catalysed by mitochondrial complex I. The regulation of this mitochondrial enzyme is not completely understood. An interesting characteristic of complex I from some organisms is the ability to adopt two distinct states: the so-called catalytically active (A) and the de-active, dormant state (D). The A-form in situ can undergo de-activation when the activity of the respiratory chain is limited (i.e. in the absence of oxygen). The mechanisms and driving force behind the A/D transition of the enzyme are currently unknown, but several subunits are most likely involved in the conformational rearrangements: the accessory subunit 39 kDa (NDUFA9) and the mitochondrially encoded subunits, ND3 and ND1. These three subunits are located in the region of the quinone binding site. The A/D transition could represent an intrinsic mechanism which provides a fast response of the mitochondrial respiratory chain to oxygen deprivation. The physiological role of the accumulation of the D-form in anoxia is most probably to protect mitochondria from ROS generation due to the rapid burst of respiration following reoxygenation. The de-activation rate varies in different tissues and can be modulated by the temperature, the presence of free fatty acids and divalent cations, the NAD+/NADH ratio in the matrix, the presence of nitric oxide and oxygen availability. Cysteine-39 of the ND3 subunit, exposed in the D-form, is susceptible to covalent modification by nitrosothiols, ROS and RNS. The D-form in situ could react with natural effectors in mitochondria or with pharmacological agents. Therefore the modulation of the re-activation rate of complex I could be a way to ameliorate the ischaemia/reperfusion damage. This article is part of a Special Issue entitled: 18th European Bioenergetic Conference. Guest Editors: Manuela Pereira and Miguel Teixeira. The potential mechanism of complex I A/D transition is discussed. An —SH group exposed in the D-form is susceptible to covalent modification. The role of A/D transition in tissue response to ischaemia is proposed.
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Affiliation(s)
- Marion Babot
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Amanda Birch
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Paola Labarbuta
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Alexander Galkin
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK.
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Kalashnikov DS, Grivennikova VG, Vinogradov AD. Synergetic inhibition of the brain mitochondrial NADH: Ubiquinone oxidoreductase (Complex I) by fatty acids and Ca2+. BIOCHEMISTRY (MOSCOW) 2011; 76:968-75. [DOI: 10.1134/s000629791108013x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Loskovich M, Grivennikova V, Cecchini G, Vinogradov A. Inhibitory effect of palmitate on the mitochondrial NADH:ubiquinone oxidoreductase (complex I) as related to the active-de-active enzyme transition. Biochem J 2005; 387:677-83. [PMID: 15571492 PMCID: PMC1134997 DOI: 10.1042/bj20041703] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2004] [Revised: 11/23/2004] [Accepted: 11/30/2004] [Indexed: 12/30/2022]
Abstract
Palmitate rapidly and reversibly inhibits the uncoupled NADH oxidase activity catalysed by activated complex I in inside-out bovine heart submitochondrial particles (IC50 extrapolated to zero enzyme concentration is equal to 9 microM at 25 degrees C, pH 8.0). The NADH:hexa-ammineruthenium reductase activity of complex I is insensitive to palmitate. Partial (approximately 50%) inhibition of the NADH:external quinone reductase activity is seen at saturating palmitate concentration and the residual activity is fully sensitive to piericidin. The uncoupled succinate oxidase activity is considerably less sensitive to palmitate. Only a slight stimulation of tightly coupled respiration with NADH as the substrate is seen at optimal palmitate concentrations, whereas complete relief of the respiratory control is observed with succinate as the substrate. Palmitate prevents the turnover-induced activation of the de-activated complex I (IC50 extrapolated to zero enzyme concentration is equal to 3 microM at 25 degrees C, pH 8.0). The mode of action of palmitate on the NADH oxidase is qualitatively temperature-dependent. Rapid and reversible inhibition of the complex I catalytic activity and its de-active to active state transition are seen at 25 degrees C, whereas the time-dependent irreversible inactivation of the NADH oxidase proceeds at 37 degrees C. Palmitate drastically increases the rate of spontaneous de-activation of complex I in the absence of NADH. Taken together, these results suggest that free fatty acids act as specific complex I-directed inhibitors; at a physiologically relevant temperature (37 degrees C), their inhibitory effects on mitochondrial NADH oxidation is due to perturbation of the pseudo-reversible active-de-active complex I transition.
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Affiliation(s)
- Maria V. Loskovich
- *Department of Biochemistry, School of Biology, Moscow State University, Moscow 119992, Russia
| | - Vera G. Grivennikova
- *Department of Biochemistry, School of Biology, Moscow State University, Moscow 119992, Russia
| | - Gary Cecchini
- †Molecular Biology Division, Veterans Affairs Medical Center, San Francisco, CA 94141, U.S.A
- ‡Department of Biochemistry and Biophysics, University of California, San Francisco, CA 94143, U.S.A
| | - Andrei D. Vinogradov
- *Department of Biochemistry, School of Biology, Moscow State University, Moscow 119992, Russia
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Grivennikova VG, Ushakova AV, Cecchini G, Vinogradov AD. Unidirectional effect of lauryl sulfate on the reversible NADH:ubiquinone oxidoreductase (Complex I). FEBS Lett 2003; 549:39-42. [PMID: 12914921 DOI: 10.1016/s0014-5793(03)00765-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Lauryl sulfate inhibits the Deltamu;(H)(+)-dependent reverse electron transfer reactions catalyzed by NADH:ubiquinone oxidoreductase (Complex I) in coupled bovine heart submitochondrial particles and in vesicles derived from Paracoccus denitrificans. The inhibitor affects neither NADH oxidase (coupled or uncoupled) nor NADH:ferricyanide reductase and succinate oxidase activities at the concentrations that selectively prevent the succinate-supported, rotenone-sensitive NAD(+) or ferricyanide reduction. Possible uncoupling effects of the inhibitor are ruled out: in contrast to oligomycin and gramicidin, which increases and decreases the rate of the reverse electron transfer, respectively, in parallel with their coupling and uncoupling effects, lauryl sulfate does not affect the respiratory control ratio. A mechanistic model for the unidirectional effect of lauryl sulfate on the Complex I catalyzed oxidoreduction is proposed.
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Affiliation(s)
- V G Grivennikova
- Department of Biochemistry, School of Biology, Moscow State University, Moscow 119992, Russia
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Grivennikova VG, Kapustin AN, Vinogradov AD. Catalytic activity of NADH-ubiquinone oxidoreductase (complex I) in intact mitochondria. evidence for the slow active/inactive transition. J Biol Chem 2001; 276:9038-44. [PMID: 11124957 DOI: 10.1074/jbc.m009661200] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The mammalian purified dispersed NADH-ubiquinone oxidoreductase (Complex I) and the enzyme in inside-out submitochondrial particles are known to be the slowly equilibrating mixture of the active and de-activated forms (Vinogradov, A. D. (1998) Biochim. Biophys. Acta 1364, 169-185). We report here the phenomenon of slow active/de-active transition in intact mitochondria where the enzyme is located within its natural environment being exposed to numerous mitochondrial matrix proteins. A simple procedure for permeabilization of intact mitochondria by channel-forming antibiotic alamethicin was worked out for the "in situ" assay of Complex I activity. Alamethicin-treated mitochondria catalyzed the rotenone-sensitive NADH-quinone reductase reaction with exogenousely added NADH and quinone-acceptor at the rates expected if the enzyme active sites would be freely accessible for the substrates. The matrix proteins were retained in alamethicin-treated mitochondria as judged by their high rotenone-sensitive malate-cytochrome c reductase activity in the presence of added NAD(+). The sensitivity of Complex I to N-ethylmaleimide and to the presence of Mg(2+) was used as the diagnostic tools to detect the presence of the de-activated enzyme. The NADH-quinone reductase activity of alamethicin-treated mitochondria was sensitive to neither N-ethylmaleimide nor Mg(2+). After exposure to elevated temperature (37 degrees C, the conditions known to induce de-activation of Complex I) the enzyme activity became sensitive to the sulfhydryl reagent and/or Mg(2+). The sensitivity to both inhibitors disappeared after brief exposure of the thermally de-activated mitochondria with malate/glutamate, NAD(+), and cytochrome c (the conditions known for the turnover-induced reactivation of the enzyme). We conclude that the slow active/de-active Complex I transition is a characteristic feature of the enzyme in intact mitochondria and discuss its possible physiological significance.
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Affiliation(s)
- V G Grivennikova
- Department of Biochemistry, School of Biology, Moscow State University, Moscow 119899, Russian Federation
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Korte F, Kvesitadze G, Ugrekhelidze D, Gordeziani M, Khatisashvili G, Buadze O, Zaalishvili G, Coulston F. Organic toxicants and plants. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2000; 47:1-26. [PMID: 10993699 DOI: 10.1006/eesa.2000.1929] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Organic xenobiotics absorbed by roots and leaves of higher plants are translocated by different physiological mechanisms. The following pathways of xenobiotic detoxication have been observed in higher plants: conjugation with such endogenous compounds as peptides, sugars, amino acids, and organic acids; oxidative degradation and consequent oxidation of xenobiotics with the final participation of their carbon atoms in regular cell metabolism. The small parts of xenobiotics are excreted maintaining their original structure and configuration. Enzymes catalyze oxidative degradation of xenobiotics from the initial hydroxylation to their deep oxidation. The wide intracellular distribution and inductive nature of oxidative enzymes lead to the high detoxication ability. With plant aging, transformation of the monooxygenase system into peroxidase takes place. Once in the cells, xenobiotics are incorporated into different cell organelles. All xenobiotics examined are characterized by a negative effect on cell ultrastructure. The penetration of high doses of xenobiotics into plant cells leads to significant deviations from the norm and, in some cases, even to the complete cell destruction and plant death.
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Affiliation(s)
- F Korte
- Durmishidze Institute of Plant Biochemistry, Academy of Sciences of Georgia, Digomi, Tbilisi, 380059, Georgia
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Ushakova AV, Grivennikova VG, Ohnishi T, Vinogradov AD. Triton X-100 as a specific inhibitor of the mammalian NADH-ubiquinone oxidoreductase (Complex I). BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1409:143-53. [PMID: 9878712 DOI: 10.1016/s0005-2728(98)00156-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Triton X-100 inhibits the NADH oxidase and rotenone-sensitive NADH-Q1 reductase activities of bovine heart submitochondrial particles (SMP) with an apparent Ki of 1x10-5 M (pH 8.0, 25 degrees C). The NADH-hexammineruthenium reductase, succinate oxidase, and the respiratory control ratio with succinate as the substrate in tightly coupled SMP are not affected at the inhibitor concentrations below 0.15 mM. The succinate-supported aerobic reverse electron transfer is less sensitive to the inhibitor (Ki=5x10-5 M) than NADH oxidase. Similar to rotenone, limited concentrations of Triton X-100 increase the steady-state level of NAD+ reduction when the nucleotide is added to tightly coupled SMP oxidizing succinate aerobically. Also similar to rotenone, Triton X-100 partially protects Complex I against the thermally induced deactivation and partially activates the thermally deactivated enzyme. The rate of the NADH oxidase inhibition by rotenone is drastically decreased in the presence of Triton X-100 which indicates a competition between these two inhibitors for a common specific binding site. In contrast to rotenone, the inhibitory effect of Triton X-100 is instantly reversed upon dilution of the reaction mixture. The NADH-Q1 reductase activity of SMP is inhibited non-competitively by added Q1 whereas a simple competition between Q1 and the inhibitor is seen for isolated Complex I. The results obtained show that Triton X-100 is a specific inhibitor of the ubiquinone reduction by Complex I and are in accord with our previous findings which suggest that different reaction pathways operate in the forward and reverse electron transfer at this segment of the mammalian respiratory chain.
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Affiliation(s)
- A V Ushakova
- Department of Biochemistry, School of Biology, Moscow State University, 119899 Moscow, Russia
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Ohki N, Kimura T, Ogata Y. The reduction of methemoglobin in Neo Red Cell. ARTIFICIAL CELLS, BLOOD SUBSTITUTES, AND IMMOBILIZATION BIOTECHNOLOGY 1998; 26:477-85. [PMID: 9844714 DOI: 10.3109/10731199809117468] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The hemoglobin oxidation factors that produce methemoglobin (metHb) were studied, for example, loss of enzymatic activity, lack of electron carrier and effect of lipids. The adverse effect of lipids is very pronounced and must be eliminated as much as possible in the producing Neo Red Cell (NRC). The process of swelling was studied. Liquid for swelling was varied from water to basic liquids. The pH of swollen lipids varied from acidic to neutral or basic, metHb was decreased and the enzymes in the Embden-Meyerhof pathway were activated. Phosphatidylcholine (PC) which is a component of mixed lipids is decomposed to lisophosphatidylcholine (liso-PC) in basic pH liquids, but liso-PC formation was not detected when the pH of swollen lipids was under 7.8. For both metHb formation and PC decomposition, swelling with the same quantity of 0.2 N aqueous sodium hydroxide proved optimal.
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Affiliation(s)
- N Ohki
- R&D Center, Terumo Corporation, Kanagawa, Japan
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Tyni T, Majander A, Kalimo H, Rapola J, Pihko H. Pathology of skeletal muscle and impaired respiratory chain function in long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency with the G1528C mutation. Neuromuscul Disord 1996; 6:327-37. [PMID: 8938697 DOI: 10.1016/0960-8966(96)00352-5] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Lactic acidosis and mitochondrial abnormalities have been reported in long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency. We studied muscle morphology and the respiratory chain function in ten patients with LCHAD deficiency and the G1528C mutation. In eight cases the light microscopy of muscle specimens showed fatty infiltration and fibre degeneration. The degenerated fibres appeared as ragged red fibres in four cases. Electron microscopy revealed enlarged mitochondria often with swollen appearance in four out of seven patients. The number of mitochondria had also increased. Complex I associated enzyme activities in muscle mitochondria were decreased in five out of seven patients, and in three of them Complex II or II + III associated activities were also affected. We suggest that the reason for respiratory chain dysfunction and structural changes of mitochondria is the accumulation of toxic intermediates of fatty acid beta-oxidation in mitochondria. Because these changes may confound the differential diagnostics between LCHAD deficiency and respiratory chain defects, awareness of their frequency is important.
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Affiliation(s)
- T Tyni
- Department of Child Neurology, Children's Hospital, University of Helsinki, Finland.
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Detrimental effects of fatty acids and their derivatives in ischemic and reperfused myocardium. PATHOPHYSIOLOGY OF SEVERE ISCHEMIC MYOCARDIAL INJURY 1990. [DOI: 10.1007/978-94-009-0475-0_8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Stucki JW, Lehmann LH, Siegel E. Acylation of Proteins by Myristic Acid in Isolated Mitochondria. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)83359-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Salon C, Raymond P, Pradet A. Quantification of carbon fluxes through the tricarboxylic acid cycle in early germinating lettuce embryos. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(18)37752-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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