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Moon SH, Liu X, Jenkins CM, Dilthey BG, Patti GJ, Gross RW. Etomoxir-carnitine, a novel pharmaco-metabolite of etomoxir, inhibits phospholipases A 2 and mitochondrial respiration. J Lipid Res 2024; 65:100611. [PMID: 39094773 PMCID: PMC11402452 DOI: 10.1016/j.jlr.2024.100611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 07/23/2024] [Accepted: 07/24/2024] [Indexed: 08/04/2024] Open
Abstract
Mitochondrial fatty acid oxidation serves as an essential process for cellular survival, differentiation, proliferation, and energy metabolism. Numerous studies have utilized etomoxir (ETO) for the irreversible inhibition of carnitine palmitoylcarnitine transferase 1 (CPT1), which catalyzes the rate-limiting step for mitochondrial long-chain fatty acid β-oxidation to examine the bioenergetic roles of mitochondrial fatty acid metabolism in many tissues in multiple diverse disease states. Herein, we demonstrate that intact mitochondria robustly metabolize ETO to etomoxir-carnitine (ETO-carnitine) prior to nearly complete ETO-mediated inhibition of CPT1. The novel pharmaco-metabolite, ETO-carnitine, was conclusively identified by accurate mass, fragmentation patterns, and isotopic fine structure. On the basis of these data, ETO-carnitine was successfully differentiated from isobaric structures (e.g., 3-hydroxy-C18:0 carnitine and 3-hydroxy-C18:1 carnitine). Mechanistically, generation of ETO-carnitine from mitochondria required exogenous Mg2+, ATP or ADP, CoASH, and L-carnitine, indicating that thioesterification by long-chain acyl-CoA synthetase to form ETO-CoA precedes its conversion to ETO-carnitine by CPT1. CPT1-dependent generation of ETO-carnitine was substantiated by an orthogonal approach using ST1326 (a CPT1 inhibitor), which effectively inhibits mitochondrial ETO-carnitine production. Surprisingly, purified ETO-carnitine potently inhibited calcium-independent PLA2γ and PLA2β as well as mitochondrial respiration independent of CPT1. Robust production and release of ETO-carnitine from HepG2 cells incubated in the presence of ETO was also demonstrated. Collectively, this study identifies the chemical mechanism for the biosynthesis of a novel pharmaco-metabolite of ETO, ETO-carnitine, that is generated by CPT1 in mitochondria and likely impacts multiple downstream (non-CPT1 related) enzymes and processes in multiple subcellular compartments.
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Affiliation(s)
- Sung Ho Moon
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA
| | - Xinping Liu
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA
| | - Christopher M Jenkins
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA
| | - Beverly Gibson Dilthey
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA
| | - Gary J Patti
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA; Department of Chemistry, Washington University, Saint Louis, MO, USA; Siteman Cancer Center, Washington University in St. Louis, Saint Louis, MO, USA; Center for Metabolomics and Isotope Tracing, Washington University in St. Louis, Saint Louis, MO, USA
| | - Richard W Gross
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA; Department of Chemistry, Washington University, Saint Louis, MO, USA; Department of Developmental Biology, Washington University School of Medicine, Saint Louis, MO, USA; Center for Cardiovascular Research, Washington University School of Medicine, Saint Louis, MO, USA.
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Stein CS, Zhang X, Witmer NH, Pennington ER, Shaikh SR, Boudreau RL. Mitoregulin supports mitochondrial membrane integrity and protects against cardiac ischemia-reperfusion injury. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.31.596875. [PMID: 38853979 PMCID: PMC11160723 DOI: 10.1101/2024.05.31.596875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
We and others discovered a highly-conserved mitochondrial transmembrane microprotein, named Mitoregulin (Mtln), that supports lipid metabolism. We reported that Mtln strongly binds cardiolipin (CL), increases mitochondrial respiration and Ca 2+ retention capacities, and reduces reactive oxygen species (ROS). Here we extend our observation of Mtln-CL binding and examine Mtln influence on cristae structure and mitochondrial membrane integrity during stress. We demonstrate that mitochondria from constitutive- and inducible Mtln-knockout (KO) mice are susceptible to membrane freeze-damage and that this can be rescued by acute Mtln re-expression. In mitochondrial-simulated lipid monolayers, we show that synthetic Mtln decreases lipid packing and monolayer elasticity. Lipidomics revealed that Mtln-KO heart tissues show broad decreases in 22:6-containing lipids and increased cardiolipin damage/remodeling. Lastly, we demonstrate that Mtln-KO mice suffer worse myocardial ischemia-reperfusion injury, hinting at a translationally-relevant role for Mtln in cardioprotection. Our work supports a model in which Mtln binds cardiolipin and stabilizes mitochondrial membranes to broadly influence diverse mitochondrial functions, including lipid metabolism, while also protecting against stress.
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Zhou PY, Zhu DX, Chen YJ, Feng QY, Mao YH, Zhuang AB, Xu JM. High patatin like phospholipase domain containing 8 expression as a biomarker for poor prognosis of colorectal cancer. World J Gastrointest Oncol 2024; 16:787-797. [PMID: 38577466 PMCID: PMC10989391 DOI: 10.4251/wjgo.v16.i3.787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 12/19/2023] [Accepted: 01/22/2024] [Indexed: 03/12/2024] Open
Abstract
BACKGROUND Patatin like phospholipase domain containing 8 (PNPLA8) has been shown to play a significant role in various cancer entities. Previous studies have focused on its roles as an antioxidant and in lipid peroxidation. However, the role of PNPLA8 in colorectal cancer (CRC) progression is unclear. AIM To explore the prognostic effects of PNPLA8 expression in CRC. METHODS A retrospective cohort containing 751 consecutive CRC patients was enrolled. PNPLA8 expression in tumor samples was evaluated by immunohistochemistry staining and semi-quantitated with immunoreactive scores. CRC patients were divided into high and low PNPLA8 expression groups based on the cut-off values, which were calculated by X-tile software. The prognostic value of PNPLA8 was identified using univariate and multivariate Cox regression analysis. The overall survival (OS) rates of CRC patients in the study cohort were compared with Kaplan-Meier analysis and Log-rank test. RESULTS PNPLA8 expression was significantly associated with distant metastases in our cohort (P = 0.048). CRC patients with high PNPLA8 expression indicated poor OS (median OS = 35.3, P = 0.005). CRC patients with a higher PNPLA8 expression at either stage I and II or stage III and IV had statistically significant shorter OS. For patients with left-sided colon and rectal cancer, the survival curves of two PNPLA8-expression groups showed statistically significant differences. Multivariate analysis also confirmed that high PNPLA8 expression was an independent prognostic factor for overall survival (hazard ratio HR = 1.328, 95%CI: 1.016-1.734, P = 0.038). CONCLUSION PNPLA8 is a novel independent prognostic factor for CRC. These findings suggest that PNPLA8 is a potential target in clinical CRC management.
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Affiliation(s)
- Peng-Yang Zhou
- Department of General Surgery, Zhongshan Hospital Fudan University, Shanghai 200032, China
| | - De-Xiang Zhu
- Department of General Surgery, Zhongshan Hospital Fudan University, Shanghai 200032, China
| | - Yi-Jiao Chen
- Department of General Surgery, Zhongshan Hospital Fudan University, Shanghai 200032, China
| | - Qing-Yang Feng
- Department of General Surgery, Zhongshan Hospital Fudan University, Shanghai 200032, China
| | - Yi-Hao Mao
- Department of General Surgery, Zhongshan Hospital Fudan University, Shanghai 200032, China
| | - Ao-Bo Zhuang
- Department of General Surgery, Zhongshan Hospital Fudan University, Shanghai 200032, China
| | - Jian-Min Xu
- Department of General Surgery, Zhongshan Hospital Fudan University, Shanghai 200032, China
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4
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Camargo-Escalante MO, Balcázar-López E, Albores Méndez EM, Winkler R, Herrera-Estrella A. LOX1- and PLP1-dependent transcriptional reprogramming is essential for injury-induced conidiophore development in a filamentous fungus. Microbiol Spectr 2023; 11:e0260723. [PMID: 37943049 PMCID: PMC10714772 DOI: 10.1128/spectrum.02607-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 10/04/2023] [Indexed: 11/10/2023] Open
Abstract
IMPORTANCE In addition to being considered a biocontrol agent, the fungus Trichoderma atroviride is a relevant model for studying mechanisms of response to injury conserved in plants and animals that opens a new landscape in relation to regeneration and cell differentiation mechanisms. Here, we reveal the co-functionality of a lipoxygenase and a patatin-like phospholipase co-expressed in response to wounding in fungi. This pair of enzymes produces oxidized lipids that can function as signaling molecules or oxidative stress signals that, in ascomycetes, induce asexual development. Furthermore, we determined that both genes participate in the regulation of the synthesis of 13-HODE and the establishment of the physiological responses necessary for the formation of reproductive aerial mycelium ultimately leading to asexual development. Our results suggest an injury-induced pathway to produce oxylipins and uncovered physiological mechanisms regulated by LOX1 and PLP1 to induce conidiation, opening new hypotheses for the novo regeneration mechanisms of filamentous fungi.
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Affiliation(s)
- Martín O. Camargo-Escalante
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Cinvestav, Irapuato, Guanajuato, Mexico
| | - Edgar Balcázar-López
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Cinvestav, Irapuato, Guanajuato, Mexico
| | - Exsal M. Albores Méndez
- Escuela Militar de Graduados de Sanidad, Universidad del Ejército y Fuerza Aérea Mexicanos, Secretaría de la Defensa Nacional, Mexico City, Mexico
| | - Robert Winkler
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Cinvestav, Irapuato, Guanajuato, Mexico
| | - Alfredo Herrera-Estrella
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Cinvestav, Irapuato, Guanajuato, Mexico
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Moon SH, Dilthey BG, Guan S, Sims HF, Pittman SK, Keith AL, Jenkins CM, Weihl CC, Gross RW. Genetic deletion of skeletal muscle iPLA 2γ results in mitochondrial dysfunction, muscle atrophy and alterations in whole-body energy metabolism. iScience 2023; 26:106895. [PMID: 37275531 PMCID: PMC10239068 DOI: 10.1016/j.isci.2023.106895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 02/28/2023] [Accepted: 05/12/2023] [Indexed: 06/07/2023] Open
Abstract
Skeletal muscle is the major site of glucose utilization in mammals integrating serum glucose clearance with mitochondrial respiration. To mechanistically elucidate the roles of iPLA2γ in skeletal muscle mitochondria, we generated a skeletal muscle-specific calcium-independent phospholipase A2γ knockout (SKMiPLA2γKO) mouse. Genetic ablation of skeletal muscle iPLA2γ resulted in pronounced muscle weakness, muscle atrophy, and increased blood lactate resulting from defects in mitochondrial function impairing metabolic processing of pyruvate and resultant bioenergetic inefficiency. Mitochondria from SKMiPLA2γKO mice were dysmorphic displaying marked changes in size, shape, and interfibrillar juxtaposition. Mitochondrial respirometry demonstrated a marked impairment in respiratory efficiency with decreases in the mass and function of oxidative phosphorylation complexes and cytochrome c. Further, a pronounced decrease in mitochondrial membrane potential and remodeling of cardiolipin molecular species were prominent. Collectively, these alterations prevented body weight gain during high-fat feeding through enhanced glucose disposal without efficient capture of chemical energy thereby altering whole-body bioenergetics.
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Affiliation(s)
- Sung Ho Moon
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Beverly Gibson Dilthey
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Shaoping Guan
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Harold F. Sims
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Sara K. Pittman
- Department of Neurology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Amy L. Keith
- Department of Neurology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Christopher M. Jenkins
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Conrad C. Weihl
- Department of Neurology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Richard W. Gross
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA
- Department of Developmental Biology, Washington University School of Medicine, Saint Louis, MO 63110, USA
- Center for Cardiovascular Research, Washington University School of Medicine, Saint Louis, MO 63110, USA
- Department of Chemistry, Washington University, Saint Louis, MO 63130, USA
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6
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Lulić AM, Katalinić M. The PNPLA family of enzymes: characterisation and biological role. Arh Hig Rada Toksikol 2023; 74:75-89. [PMID: 37357879 PMCID: PMC10291501 DOI: 10.2478/aiht-2023-74-3723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 02/01/2023] [Accepted: 05/01/2023] [Indexed: 06/27/2023] Open
Abstract
This paper brings a brief review of the human patatin-like phospholipase domain-containing protein (PNPLA) family. Even though it consists of only nine members, their physiological roles and mechanisms of their catalytic activity are not fully understood. However, the results of a number of knock-out and gain- or loss-of-function research models suggest that these enzymes have an important role in maintaining the homeostasis and integrity of organelle membranes, in cell growth, signalling, cell death, and the metabolism of lipids such as triacylglycerol, phospholipids, ceramides, and retinyl esters. Research has also revealed a connection between PNPLA family member mutations or irregular catalytic activity and the development of various diseases. Here we summarise important findings published so far and discuss their structure, localisation in the cell, distribution in the tissues, specificity for substrates, and their potential physiological role, especially in view of their potential as drug targets.
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Affiliation(s)
- Ana-Marija Lulić
- Institute for Medical Research and Occupational Health, Biochemistry and Organic Analytical Chemistry Unit, Zagreb, Croatia
| | - Maja Katalinić
- Institute for Medical Research and Occupational Health, Biochemistry and Organic Analytical Chemistry Unit, Zagreb, Croatia
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7
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Manson A, Winter T, Aukema HM. Phospholipase A 2 enzymes differently impact PUFA release and oxylipin formation ex vivo in rat hearts. Prostaglandins Leukot Essent Fatty Acids 2023; 191:102555. [PMID: 36878084 DOI: 10.1016/j.plefa.2023.102555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 02/16/2023] [Accepted: 02/23/2023] [Indexed: 03/04/2023]
Abstract
Phospholipase A2 (PLA2) enzymes cleave cell membrane phospholipids and release polyunsaturated fatty acids (PUFA), which can be converted into oxylipins. However, little is known about PLA2 preference for PUFA, and even less is known about how this further impacts oxylipin formation. Therefore, we investigated the role of different PLA2 groups in PUFA release and oxylipin formation in rat hearts. Sprague-Dawley rat heart homogenates were incubated without or with varespladib (VAR), methyl arachidonyl fluorophosphonate (MAFP) or EDTA. Free PUFA and oxylipins were determined by HPLC-MS/MS, and isoform expressions by RT-qPCR. Inhibition of sPLA2 IIA and/or V by VAR reduced the release of ARA and DHA, but only DHA oxylipins were inhibited. MAFP reduced the release of ARA, DHA, ALA, and EPA, and the formation of ARA, LA, DGLA, DHA, ALA, and EPA oxylipins. Interestingly, cyclooxygenase and 12-lipoxygenase oxylipins were not inhibited. mRNA expression levels of sPLA2 and iPLA2 isoforms were highest whereas levels of cPLA2 were low, consistent with activity. In conclusion, sPLA2 enzymes lead to the formation of DHA oxylipins, while iPLA2 is likely responsible for the formation of most other oxylipins in healthy rat hearts. Oxylipin formation cannot be implied from PUFA release, thus, both should be evaluated in PLA2 activity studies.
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Affiliation(s)
- Anne Manson
- Food and Human Nutritional Sciences, University of Manitoba, Winnipeg MB, Canada; Canadian Centre for Agri-Food Research in Health and Medicine (CCARM), Winnipeg MB, Canada
| | - Tanja Winter
- Food and Human Nutritional Sciences, University of Manitoba, Winnipeg MB, Canada; Canadian Centre for Agri-Food Research in Health and Medicine (CCARM), Winnipeg MB, Canada
| | - Harold M Aukema
- Food and Human Nutritional Sciences, University of Manitoba, Winnipeg MB, Canada; Canadian Centre for Agri-Food Research in Health and Medicine (CCARM), Winnipeg MB, Canada.
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8
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Liu NK, Deng LX, Wang M, Lu QB, Wang C, Wu X, Wu W, Wang Y, Qu W, Han Q, Xia Y, Ravenscraft B, Li JL, You SW, Wipf P, Han X, Xu XM. Restoring mitochondrial cardiolipin homeostasis reduces cell death and promotes recovery after spinal cord injury. Cell Death Dis 2022; 13:1058. [PMID: 36539405 PMCID: PMC9768173 DOI: 10.1038/s41419-022-05369-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 09/06/2022] [Accepted: 10/24/2022] [Indexed: 12/24/2022]
Abstract
Alterations in phospholipids have long been associated with spinal cord injury (SCI). However, their specific roles and signaling cascades in mediating cell death and tissue repair remain unclear. Here we investigated whether alterations of cardiolipin (CL), a family of mitochondrion-specific phospholipids, play a crucial role in mitochondrial dysfunction and neuronal death following SCI. Lipidomic analysis was used to determine the profile of CL alteration in the adult rat spinal cord following a moderate contusive SCI at the 10th thoracic (T10) level. Cellular, molecular, and genetic assessments were performed to determine whether CL alterations mediate mitochondrial dysfunction and neuronal death after SCI, and, if so, whether reversing CL alteration leads to neuroprotection after SCI. Using lipidomic analysis, we uncovered CL alterations at an early stage of SCI. Over 50 distinct CL species were identified, of which 50% showed significantly decreased abundance after SCI. The decreased CL species contained mainly polyunsaturated fatty acids that are highly susceptible to peroxidation. In parallel, 4-HNE, a lipid peroxidation marker, significantly increased after SCI. We found that mitochondrial oxidative stress not only induced CL oxidation, but also resulted in CL loss by activating cPLA2 to hydrolyze CL. CL alterations induced mitochondrial dysfunction and neuronal death. Remarkably, pharmacologic inhibition of CL alterations with XJB-5-131, a novel mitochondria-targeted electron and reactive oxygen species scavenger, reduced cell death, tissue damage and ameliorated motor deficits after SCI in adult rats. These findings suggest that CL alteration could be a novel mechanism that mediates injury-induced neuronal death, and a potential therapeutic target for ameliorating secondary SCI.
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Affiliation(s)
- Nai-Kui Liu
- grid.257413.60000 0001 2287 3919Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Ling-Xiao Deng
- grid.257413.60000 0001 2287 3919Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Miao Wang
- Frontage Laboratories, Exton, PA 19341 USA
| | - Qing-Bo Lu
- grid.257413.60000 0001 2287 3919Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Chunyan Wang
- grid.4367.60000 0001 2355 7002Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110 USA
| | - Xiangbing Wu
- grid.257413.60000 0001 2287 3919Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Wei Wu
- grid.257413.60000 0001 2287 3919Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Ying Wang
- grid.257413.60000 0001 2287 3919Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Wenrui Qu
- grid.257413.60000 0001 2287 3919Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Qi Han
- grid.257413.60000 0001 2287 3919Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Yongzhi Xia
- grid.257413.60000 0001 2287 3919Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Baylen Ravenscraft
- grid.257413.60000 0001 2287 3919Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202 USA
| | - Jin-Lian Li
- grid.233520.50000 0004 1761 4404Department of Anatomy and K.K. Leung Brain Research Centre, Preclinical School of Medicine, The Fourth Military Medical University, Xi’an, 710032 P. R. China
| | - Si-Wei You
- grid.233520.50000 0004 1761 4404Institute of Neuroscience, The Fourth Military Medical University, Xi’an, P. R. China
| | - Peter Wipf
- grid.21925.3d0000 0004 1936 9000Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260 USA
| | - Xianlin Han
- grid.267309.90000 0001 0629 5880Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229 USA
| | - Xiao-Ming Xu
- grid.257413.60000 0001 2287 3919Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202 USA
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9
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Koszegi B, Balogh G, Berente Z, Vranesics A, Pollak E, Molnar L, Takatsy A, Poor V, Wahr M, Antus C, Eros K, Vigh L, Gallyas F, Peter M, Veres B. Remodeling of Liver and Plasma Lipidomes in Mice Lacking Cyclophilin D. Int J Mol Sci 2022; 23:ijms231911274. [PMID: 36232575 PMCID: PMC9569465 DOI: 10.3390/ijms231911274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 09/16/2022] [Accepted: 09/20/2022] [Indexed: 11/16/2022] Open
Abstract
In recent years, several studies aimed to investigate the metabolic effects of non-functioning or absent cyclophilin D (CypD), a crucial regulatory component of mitochondrial permeability transition pores. It has been reported that the lack of CypD affects glucose and lipid metabolism. However, the findings are controversial regarding the metabolic pathways involved, and most reports describe the effect of a high-fat diet on metabolism. We performed a lipidomic analysis of plasma and liver samples of CypD-/- and wild-type (WT) mice to reveal the lipid-specific alterations resulting from the absence of CypD. In the CypD-/- mice compared to the WT animals, we found a significant change in 52% and 47% of the measured 225 and 201 lipid species in liver and plasma samples, respectively. The higher total lipid content detected in these tissues was not accompanied by abdominal fat accumulation assessed by nuclear magnetic resonance imaging. We also documented characteristic changes in the lipid composition of the liver and plasma as a result of CypD ablation with the relative increase in polyunsaturated membrane lipid species. In addition, we did not observe remarkable differences in the lipid distribution of hepatocytes using histochemistry, but we found characteristic changes in the hepatocyte ultrastructure in CypD-/- animals using electron microscopy. Our results highlight the possible long-term effects of CypD inhibition as a novel therapeutic consideration for various diseases.
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Affiliation(s)
- Balazs Koszegi
- Department of Biochemistry and Medical Chemistry, Medical School, University of Pecs, 7624 Pecs, Hungary
| | - Gabor Balogh
- Institute of Biochemistry, Biological Research Centre, Eötvös Loránd Research Network, 6726 Szeged, Hungary
| | - Zoltan Berente
- Department of Biochemistry and Medical Chemistry, Medical School, University of Pecs, 7624 Pecs, Hungary
- Research Group for Experimental Diagnostic Imaging, University of Pecs Medical School, 7624 Pecs, Hungary
| | - Anett Vranesics
- Department of Biochemistry and Medical Chemistry, Medical School, University of Pecs, 7624 Pecs, Hungary
- Research Group for Experimental Diagnostic Imaging, University of Pecs Medical School, 7624 Pecs, Hungary
| | - Edit Pollak
- Department of Comparative Anatomy and Developmental Biology, Institute of Biology, Faculty of Natural Sciences, University of Pecs, 7624 Pecs, Hungary
| | - Laszlo Molnar
- Department of Comparative Anatomy and Developmental Biology, Institute of Biology, Faculty of Natural Sciences, University of Pecs, 7624 Pecs, Hungary
- Ecophysiological and Environmental Toxicological Research Group, Balaton Limnological Research Institute, Eötvös Loránd Research Network, 8237 Tihany, Hungary
| | - Aniko Takatsy
- Department of Biochemistry and Medical Chemistry, Medical School, University of Pecs, 7624 Pecs, Hungary
| | - Viktoria Poor
- Institute of Bioanalysis, Medical School, University of Pecs, 7624 Pecs, Hungary
| | - Matyas Wahr
- Institute of Bioanalysis, Medical School, University of Pecs, 7624 Pecs, Hungary
| | - Csenge Antus
- Department of Biochemistry and Medical Chemistry, Medical School, University of Pecs, 7624 Pecs, Hungary
| | - Krisztian Eros
- Department of Biochemistry and Medical Chemistry, Medical School, University of Pecs, 7624 Pecs, Hungary
- Szentágothai Research Centre, University of Pecs, 7624 Pecs, Hungary
| | - Laszlo Vigh
- Institute of Biochemistry, Biological Research Centre, Eötvös Loránd Research Network, 6726 Szeged, Hungary
| | - Ferenc Gallyas
- Department of Biochemistry and Medical Chemistry, Medical School, University of Pecs, 7624 Pecs, Hungary
- Szentágothai Research Centre, University of Pecs, 7624 Pecs, Hungary
- ELKH-UP Nuclear-Mitochondrial Interactions Research Group, 1245 Budapest, Hungary
| | - Maria Peter
- Institute of Biochemistry, Biological Research Centre, Eötvös Loránd Research Network, 6726 Szeged, Hungary
| | - Balazs Veres
- Department of Biochemistry and Medical Chemistry, Medical School, University of Pecs, 7624 Pecs, Hungary
- Correspondence:
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10
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The Short-Term Opening of Cyclosporin A-Independent Palmitate/Sr2+-Induced Pore Can Underlie Ion Efflux in the Oscillatory Mode of Functioning of Rat Liver Mitochondria. MEMBRANES 2022; 12:membranes12070667. [PMID: 35877870 PMCID: PMC9319229 DOI: 10.3390/membranes12070667] [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: 06/09/2022] [Revised: 06/24/2022] [Accepted: 06/27/2022] [Indexed: 11/17/2022]
Abstract
Mitochondria are capable of synchronized oscillations in many variables, but the underlying mechanisms are still unclear. In this study, we demonstrated that rat liver mitochondria, when exposed to a pulse of Sr2+ ions in the presence of valinomycin (a potassium ionophore) and cyclosporin A (a specific inhibitor of the permeability transition pore complex) under hypotonia, showed prolonged oscillations in K+ and Sr2+ fluxes, membrane potential, pH, matrix volume, rates of oxygen consumption and H2O2 formation. The dynamic changes in the rate of H2O2 production were in a reciprocal relationship with the respiration rate and in a direct relationship with the mitochondrial membrane potential and other indicators studied. The pre-incubation of mitochondria with Ca2+(Sr2+)-dependent phospholipase A2 inhibitors considerably suppressed the accumulation of free fatty acids, including palmitic and stearic acids, and all spontaneous Sr2+-induced cyclic changes. These data suggest that the mechanism of ion efflux from mitochondria is related to the opening of short-living pores, which can be caused by the formation of complexes between Sr2+(Ca2+) and endogenous long-chain saturated fatty acids (mainly, palmitic acid) that accumulate due to the activation of phospholipase A2 by the ions. A possible role for transient palmitate/Ca2+(Sr2+)-induced pores in the maintenance of ion homeostasis and the prevention of calcium overload in mitochondria under pathophysiological conditions is discussed.
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11
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Current Knowledge on Mammalian Phospholipase A1, Brief History, Structures, Biochemical and Pathophysiological Roles. Molecules 2022; 27:molecules27082487. [PMID: 35458682 PMCID: PMC9031518 DOI: 10.3390/molecules27082487] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 03/28/2022] [Accepted: 03/29/2022] [Indexed: 12/29/2022] Open
Abstract
Phospholipase A1 (PLA1) is an enzyme that cleaves an ester bond at the sn-1 position of glycerophospholipids, producing a free fatty acid and a lysophospholipid. PLA1 activities have been detected both extracellularly and intracellularly, which are well conserved in higher eukaryotes, including fish and mammals. All extracellular PLA1s belong to the lipase family. In addition to PLA1 activity, most mammalian extracellular PLA1s exhibit lipase activity to hydrolyze triacylglycerol, cleaving the fatty acid and contributing to its absorption into the intestinal tract and tissues. Some extracellular PLA1s exhibit PLA1 activities specific to phosphatidic acid (PA) or phosphatidylserine (PS) and serve to produce lysophospholipid mediators such as lysophosphatidic acid (LPA) and lysophosphatidylserine (LysoPS). A high level of PLA1 activity has been detected in the cytosol fractions, where PA-PLA1/DDHD1/iPLA1 was responsible for the activity. Many homologs of PA-PLA1 and PLA2 have been shown to exhibit PLA1 activity. Although much has been learned about the pathophysiological roles of PLA1 molecules through studies of knockout mice and human genetic diseases, many questions regarding their biochemical properties, including their genuine in vivo substrate, remain elusive.
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12
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Theodoros K, Sharma M, Anton P, Hugo C, Ellen O, Hultgren NW, Ritou E, Williams DS, Orian S S, Srinivasa T R. The ApoA-I mimetic peptide 4F attenuates in vitro replication of SARS-CoV-2, associated apoptosis, oxidative stress and inflammation in epithelial cells. Virulence 2021; 12:2214-2227. [PMID: 34494942 PMCID: PMC8437485 DOI: 10.1080/21505594.2021.1964329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 07/12/2021] [Accepted: 07/30/2021] [Indexed: 02/06/2023] Open
Abstract
An oral antiviral against SARS-CoV-2 that also attenuates inflammatory instigators of severe COVID-19 is not available to date. Herein, we show that the apoA-I mimetic peptide 4 F inhibits Spike mediated viral entry and has antiviral activity against SARS-CoV-2 in human lung epithelial Calu3 and Vero-E6 cells. In SARS-CoV-2 infected Calu3 cells, 4 F upregulated inducers of the interferon pathway such as MX-1 and Heme oxygenase 1 (HO-1) and downregulated mitochondrial reactive oxygen species (mito-ROS) and CD147, a host protein that mediates viral entry. 4 F also reduced associated cellular apoptosis and secretion of IL-6 in both SARS-CoV-2 infected Vero-E6 and Calu3 cells. Thus, 4 F attenuates in vitro SARS-CoV-2 replication, associated apoptosis in epithelial cells and secretion of IL-6, a major cytokine related to COVID-19 morbidity. Given established safety of 4 F in humans, clinical studies are warranted to establish 4 F as therapy for COVID-19.
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Affiliation(s)
- Kelesidis Theodoros
- Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Madhav Sharma
- Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Petcherski Anton
- Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Cristelle Hugo
- Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - O’Connor Ellen
- Molecular Toxicology Interdepartmental Degree Program, University of California Los Angeles, United States
| | - Nan W Hultgren
- Department of Ophthalmology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Eleni Ritou
- Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - David S Williams
- Department of Ophthalmology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Shirihai Orian S
- Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
| | - Reddy Srinivasa T
- Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA
- Molecular Toxicology Interdepartmental Degree Program, University of California Los Angeles, United States
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California, Los Angeles, California, USA
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13
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Moon SH, Dilthey BG, Liu X, Guan S, Sims HF, Gross RW. High-fat diet activates liver iPLA 2γ generating eicosanoids that mediate metabolic stress. J Lipid Res 2021; 62:100052. [PMID: 33636162 PMCID: PMC8010217 DOI: 10.1016/j.jlr.2021.100052] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 02/15/2021] [Accepted: 02/18/2021] [Indexed: 12/18/2022] Open
Abstract
High-fat (HF) diet-induced obesity precipitates multiple metabolic disorders including insulin resistance, glucose intolerance, oxidative stress, and inflammation, resulting in the initiation of cell death programs. Previously, we demonstrated murine germline knockout of calcium-independent phospholipase A2γ (iPLA2γ) prevented HF diet-induced weight gain, attenuated insulin resistance, and decreased mitochondrial permeability transition pore (mPTP) opening leading to alterations in bioenergetics. To gain insight into the specific roles of hepatic iPLA2γ in mitochondrial function and cell death under metabolic stress, we generated a hepatocyte-specific iPLA2γ-knockout (HEPiPLA2γKO). Using this model, we compared the effects of an HF diet on wild-type versus HEPiPLA2γKO mice in eicosanoid production and mitochondrial bioenergetics. HEPiPLA2γKO mice exhibited higher glucose clearance rates than WT controls. Importantly, HF-diet induced the accumulation of 12-hydroxyeicosatetraenoic acid (12-HETE) in WT liver which was decreased in HEPiPLA2γKO. Furthermore, HF-feeding markedly increased Ca2+ sensitivity and resistance to ADP-mediated inhibition of mPTP opening in WT mice. In contrast, ablation of iPLA2γ prevented the HF-induced hypersensitivity of mPTP opening to calcium and maintained ADP-mediated resistance to mPTP opening. Respirometry revealed that ADP-stimulated mitochondrial respiration was significantly reduced by exogenous 12-HETE. Finally, HEPiPLA2γKO hepatocytes were resistant to calcium ionophore-induced lipoxygenase-mediated lactate dehydrogenase release. Collectively, these results demonstrate that an HF diet increases iPLA2γ-mediated hepatic 12-HETE production leading to mitochondrial dysfunction and hepatic cell death.
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Affiliation(s)
- Sung Ho Moon
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA
| | - Beverly Gibson Dilthey
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA
| | - Xinping Liu
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA
| | - Shaoping Guan
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA
| | - Harold F Sims
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA
| | - Richard W Gross
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA; Department of Developmental Biology, Washington University School of Medicine, Saint Louis, MO, USA; Center for Cardiovascular Research, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA; Department of Chemistry, Washington University, Saint Louis, MO, USA.
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14
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Hamilton J, Brustovetsky T, Brustovetsky N. The effect of mitochondrial calcium uniporter and cyclophilin D knockout on resistance of brain mitochondria to Ca 2+-induced damage. J Biol Chem 2021; 296:100669. [PMID: 33864812 PMCID: PMC8131324 DOI: 10.1016/j.jbc.2021.100669] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 04/10/2021] [Accepted: 04/13/2021] [Indexed: 12/14/2022] Open
Abstract
The mitochondrial calcium uniporter (MCU) and cyclophilin D (CyD) are key players in induction of the permeability transition pore (PTP), which leads to mitochondrial depolarization and swelling, the major signs of Ca2+-induced mitochondrial damage. Mitochondrial depolarization inhibits ATP production, whereas swelling results in the release of mitochondrial pro-apoptotic proteins. The extent to which simultaneous deletion of MCU and CyD inhibits PTP induction and prevents damage of brain mitochondria is not clear. Here, we investigated the effects of MCU and CyD deletion on the propensity for PTP induction using mitochondria isolated from the brains of MCU-KO, CyD-KO, and newly created MCU/CyD-double knockout (DKO) mice. Neither deletion of MCU nor of CyD affected respiration or membrane potential in mitochondria isolated from the brains of these mice. Mitochondria from MCU-KO and MCU/CyD-DKO mice displayed reduced Ca2+ uptake and diminished extent of PTP induction. The Ca2+ uptake by mitochondria from CyD-KO mice was increased compared with mitochondria from WT mice. Deletion of CyD prevented mitochondrial swelling and resulted in transient depolarization in response to Ca2+, but it did not prevent Ca2+-induced delayed mitochondrial depolarization. Mitochondria from MCU/CyD-DKO mice did not swell in response to Ca2+, but they did exhibit mild sustained depolarization. Dibucaine, an inhibitor of the Ca2+-activated mitochondrial phospholipase A2, attenuated and bovine serum albumin completely eliminated the sustained depolarization. This suggests the involvement of phospholipase A2 and free fatty acids. Thus, in addition to induction of the classical PTP, alternative deleterious mechanisms may contribute to mitochondrial damage following exposure to elevated Ca2+.
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Affiliation(s)
- James Hamilton
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Tatiana Brustovetsky
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Nickolay Brustovetsky
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana, USA; Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, Indiana, USA.
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15
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Murakami M, Sato H, Taketomi Y. Updating Phospholipase A 2 Biology. Biomolecules 2020; 10:E1457. [PMID: 33086624 PMCID: PMC7603386 DOI: 10.3390/biom10101457] [Citation(s) in RCA: 106] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 10/09/2020] [Accepted: 10/15/2020] [Indexed: 12/30/2022] Open
Abstract
The phospholipase A2 (PLA2) superfamily contains more than 50 enzymes in mammals that are subdivided into several distinct families on a structural and biochemical basis. In principle, PLA2 has the capacity to hydrolyze the sn-2 position of glycerophospholipids to release fatty acids and lysophospholipids, yet several enzymes in this superfamily catalyze other reactions rather than or in addition to the PLA2 reaction. PLA2 enzymes play crucial roles in not only the production of lipid mediators, but also membrane remodeling, bioenergetics, and body surface barrier, thereby participating in a number of biological events. Accordingly, disturbance of PLA2-regulated lipid metabolism is often associated with various diseases. This review updates the current state of understanding of the classification, enzymatic properties, and biological functions of various enzymes belonging to the PLA2 superfamily, focusing particularly on the novel roles of PLA2s in vivo.
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Affiliation(s)
- Makoto Murakami
- Laboratory of Microenvironmental and Metabolic Health Sciences, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan; (H.S.); (Y.T.)
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16
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Liang G, Wu R, Jiang L, Liu Y, Mao G, Huang Z, Qi L, Jiang H. The role of lipoprotein-associated phospholipase A2 in acute kidney injury of septic mice. Transl Androl Urol 2020; 9:2192-2199. [PMID: 33209683 PMCID: PMC7658152 DOI: 10.21037/tau-20-1173] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Background This experiment aimed to investigate the role and mechanism of lipoprotein-associated phospholipase A2 (Lp-PLA2) in kidney injury in septic mice induced by cecal ligation and perforation (CLP). Methods Male BALB/c mice were randomly divided into two groups: sham-operation group (Sham group) and septic group (CLP group). The septic model was simulated by cecal ligation and puncture method, but only cecal ligation was used for the sham operation group. The whole serum and renal tissue samples of the mice were collected 24 hours after modeling in both groups. Hematoxylin-eosin (HE) staining was used to observe the pathological changes of renal tissue, the renal injury score was recorded, and the creatinine (Cr) and blood urea nitrogen (BUN) levels were detected by automatic biochemical analyzer, while the serum Lp-PLA2 level was detected by enzyme-linked immunosorbent assay (ELISA). The 7-day survival rate and the survival curve of the two groups were statistically analyzed. Results Compared with the Sham group, the pathological score of renal injury in the CLP Group was higher, the level of Lp-PLA2 in serum was significantly increased (all P<0.01), and the expression of Lp-PLA2 in renal tissue was significantly elevated (all P<0.01). Furthermore, the 7-day survival rate of the Sham group was 90%, while that of CLP group was 25%. Conclusions The expression level of Lp-PLA2 in blood and kidney tissue of septic mice was increased and correlated with prognosis. However, the predictive value of Lp-PLA2 for prognosis in septic mice needs further study.
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Affiliation(s)
- Guiwen Liang
- Department of Emergency Medicine, Affiliated Hospital of Nantong University, Nantong, China
| | - Ruo Wu
- Department of Emergency Medicine, Affiliated Hospital of Nantong University, Nantong, China
| | - Lan Jiang
- Department of Gastroenterology, First People's Hospital of Zhangjiagang City, Zhangjiagang, China
| | - Yanfang Liu
- Department of Anesthesiology, Affiliated Hospital of Nantong University, Nantong, China
| | - Guomin Mao
- Department of Emergency Medicine, Affiliated Hospital of Nantong University, Nantong, China
| | - Zhongwei Huang
- Department of Emergency Medicine, Affiliated Hospital of Nantong University, Nantong, China
| | - Lei Qi
- Department of Emergency Medicine, Affiliated Hospital of Nantong University, Nantong, China
| | - Haiyan Jiang
- Department of Emergency Medicine, Affiliated Hospital of Nantong University, Nantong, China
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17
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Liu X, Sims HF, Jenkins CM, Guan S, Dilthey BG, Gross RW. 12-LOX catalyzes the oxidation of 2-arachidonoyl-lysolipids in platelets generating eicosanoid-lysolipids that are attenuated by iPLA 2γ knockout. J Biol Chem 2020; 295:5307-5320. [PMID: 32161117 PMCID: PMC7170522 DOI: 10.1074/jbc.ra119.012296] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 03/04/2020] [Indexed: 12/13/2022] Open
Abstract
The canonical pathway of eicosanoid production in most mammalian cells is initiated by phospholipase A2-mediated release of arachidonic acid, followed by its enzymatic oxidation resulting in a vast array of eicosanoid products. However, recent work has demonstrated that the major phospholipase in mitochondria, iPLA2γ (patatin-like phospholipase domain containing 8 (PNPLA8)), possesses sn-1 specificity, with polyunsaturated fatty acids at the sn-2 position generating polyunsaturated sn-2-acyl lysophospholipids. Through strategic chemical derivatization, chiral chromatographic separation, and multistage tandem MS, here we first demonstrate that human platelet-type 12-lipoxygenase (12-LOX) can directly catalyze the regioselective and stereospecific oxidation of 2-arachidonoyl-lysophosphatidylcholine (2-AA-LPC) and 2-arachidonoyl-lysophosphatidylethanolamine (2-AA-LPE). Next, we identified these two eicosanoid-lysophospholipids in murine myocardium and in isolated platelets. Moreover, we observed robust increases in 2-AA-LPC, 2-AA-LPE, and their downstream 12-LOX oxidation products, 12(S)-HETE-LPC and 12(S)-HETE-LPE, in calcium ionophore (A23187)-stimulated murine platelets. Mechanistically, genetic ablation of iPLA2γ markedly decreased the calcium-stimulated production of 2-AA-LPC, 2-AA-LPE, and 12-HETE-lysophospholipids in mouse platelets. Importantly, a potent and selective 12-LOX inhibitor, ML355, significantly inhibited the production of 12-HETE-LPC and 12-HETE-LPE in activated platelets. Furthermore, we found that aging is accompanied by significant changes in 12-HETE-LPC in murine serum that were also markedly attenuated by iPLA2γ genetic ablation. Collectively, these results identify previously unknown iPLA2γ-initiated signaling pathways mediated by direct 12-LOX oxidation of 2-AA-LPC and 2-AA-LPE. This oxidation generates previously unrecognized eicosanoid-lysophospholipids that may serve as biomarkers for age-related diseases and could potentially be used as targets in therapeutic interventions.
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Affiliation(s)
- Xinping Liu
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri 63110
| | - Harold F Sims
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri 63110
| | - Christopher M Jenkins
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri 63110
| | - Shaoping Guan
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri 63110
| | - Beverly G Dilthey
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri 63110
| | - Richard W Gross
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri 63110; Department of Developmental Biology, Washington University School of Medicine, Saint Louis, Missouri 63110; Department of Chemistry, Washington University, Saint Louis, Missouri 63130.
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18
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Tyurina YY, St Croix CM, Watkins SC, Watson AM, Epperly MW, Anthonymuthu TS, Kisin ER, Vlasova II, Krysko O, Krysko DV, Kapralov AA, Dar HH, Tyurin VA, Amoscato AA, Popova EN, Bolevich SB, Timashev PS, Kellum JA, Wenzel SE, Mallampalli RK, Greenberger JS, Bayir H, Shvedova AA, Kagan VE. Redox (phospho)lipidomics of signaling in inflammation and programmed cell death. J Leukoc Biol 2019; 106:57-81. [PMID: 31071242 PMCID: PMC6626990 DOI: 10.1002/jlb.3mir0119-004rr] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Revised: 04/12/2019] [Accepted: 04/19/2019] [Indexed: 02/06/2023] Open
Abstract
In addition to the known prominent role of polyunsaturated (phospho)lipids as structural blocks of biomembranes, there is an emerging understanding of another important function of these molecules as a highly diversified signaling language utilized for intra- and extracellular communications. Technological developments in high-resolution mass spectrometry facilitated the development of a new branch of metabolomics, redox lipidomics. Analysis of lipid peroxidation reactions has already identified specific enzymatic mechanisms responsible for the biosynthesis of several unique signals in response to inflammation and regulated cell death programs. Obtaining comprehensive information about millions of signals encoded by oxidized phospholipids, represented by thousands of interactive reactions and pleiotropic (patho)physiological effects, is a daunting task. However, there is still reasonable hope that significant discoveries, of at least some of the important contributors to the overall overwhelmingly complex network of interactions triggered by inflammation, will lead to the discovery of new small molecule regulators and therapeutic modalities. For example, suppression of the production of AA-derived pro-inflammatory mediators, HXA3 and LTB4, by an iPLA2 γ inhibitor, R-BEL, mitigated injury associated with the activation of pro-inflammatory processes in animals exposed to whole-body irradiation. Further, technological developments promise to make redox lipidomics a powerful approach in the arsenal of diagnostic and therapeutic instruments for personalized medicine of inflammatory diseases and conditions.
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Affiliation(s)
- Yulia Y Tyurina
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Claudette M St Croix
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Simon C Watkins
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Alan M Watson
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Michael W Epperly
- Department of Radiation Oncology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Tamil S Anthonymuthu
- Department of Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Elena R Kisin
- Exposure Assessment Branch, NIOSH/CDC, Morgantown, West Virginia, USA
| | - Irina I Vlasova
- Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow, Russia
- Laboratory of Navigational Redox Lipidomics, IM Sechenov Moscow State Medical University, Moscow, Russia
| | - Olga Krysko
- Upper Airways Research Laboratory, Department of Head and Skin, Ghent University, and Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | - Dmitri V Krysko
- Cell Death Investigation and Therapy Laboratory, Department of Human Structure and Repair, Ghent University, and Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | - Alexandr A Kapralov
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Haider H Dar
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Vladimir A Tyurin
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Andrew A Amoscato
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Elena N Popova
- Laboratory of Navigational Redox Lipidomics, IM Sechenov Moscow State Medical University, Moscow, Russia
| | - Sergey B Bolevich
- Laboratory of Navigational Redox Lipidomics, IM Sechenov Moscow State Medical University, Moscow, Russia
| | - Peter S Timashev
- Laboratory of Navigational Redox Lipidomics, IM Sechenov Moscow State Medical University, Moscow, Russia
| | - John A Kellum
- Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Sally E Wenzel
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | | | - Joel S Greenberger
- Department of Radiation Oncology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Hulya Bayir
- Department of Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Anna A Shvedova
- Exposure Assessment Branch, NIOSH/CDC, Morgantown, West Virginia, USA
| | - Valerian E Kagan
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Laboratory of Navigational Redox Lipidomics, IM Sechenov Moscow State Medical University, Moscow, Russia
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Shukla A, Saneto RP, Hebbar M, Mirzaa G, Girisha KM. A neurodegenerative mitochondrial disease phenotype due to biallelic loss-of-function variants in PNPLA8 encoding calcium-independent phospholipase A2γ. Am J Med Genet A 2019; 176:1232-1237. [PMID: 29681094 DOI: 10.1002/ajmg.a.38687] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 03/05/2018] [Accepted: 03/05/2018] [Indexed: 12/19/2022]
Abstract
Animal studies have demonstrated the critical roles of the patatin-like protein family plays in cellular growth, lipid homeostasis, and second messenger signaling the nervous system. Of the nine known calcium-independent phospholipase A2γ, only PNPLA2, PNLPA6, PNPLA9 and most recently a single patient with PNPLA8 are associated with mitochondrial-related neurodegeneration. Using whole exome sequencing, we report two unrelated individuals with variable but similar clinical features of microcephaly, severe global developmental delay, spasticity, lactic acidosis, and progressive cerebellar atrophy with biallelic loss-of-function variants in PNPLA8.
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Affiliation(s)
- Anju Shukla
- Department of Medical Genetics, Kasturba Medical College, Manipal Academy of Higher Education, Manipal, India
| | - Russell P Saneto
- Center for Integrative Brain Research, Neuroscience Institute, Seattle Children's Research Institute, Seattle, Washington, USA.,Division of Pediatric Neurology, Department of Neurology, Neuroscience Institute, Seattle Children's Hospital, Seattle, Washington, USA
| | - Malavika Hebbar
- Department of Medical Genetics, Kasturba Medical College, Manipal Academy of Higher Education, Manipal, India
| | - Ghayda Mirzaa
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington, USA.,Department of Pediatrics, University of Washington, Seattle, Washington, USA
| | - Katta M Girisha
- Department of Medical Genetics, Kasturba Medical College, Manipal Academy of Higher Education, Manipal, India
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20
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Liu GY, Moon SH, Jenkins CM, Sims HF, Guan S, Gross RW. Synthesis of oxidized phospholipids by sn-1 acyltransferase using 2-15-HETE lysophospholipids. J Biol Chem 2019; 294:10146-10159. [PMID: 31080170 DOI: 10.1074/jbc.ra119.008766] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 05/10/2019] [Indexed: 01/13/2023] Open
Abstract
Recently, oxidized phospholipid species have emerged as important signaling lipids in activated immune cells and platelets. The canonical pathway for the synthesis of oxidized phospholipids is through the release of arachidonic acid by cytosolic phospholipase A2α (cPLA2α) followed by its enzymatic oxidation, activation of the carboxylate anion by acyl-CoA synthetase(s), and re-esterification to the sn-2 position by sn-2 acyltransferase activity (i.e. the Lands cycle). However, recent studies have demonstrated the unanticipated significance of sn-1 hydrolysis of arachidonoyl-containing choline and ethanolamine glycerophospholipids by other phospholipases to generate the corresponding 2-arachidonoyl-lysolipids. Herein, we identified a pathway for oxidized phospholipid synthesis comprising sequential sn-1 hydrolysis by a phospholipase A1 (e.g. by patatin-like phospholipase domain-containing 8 (PNPLA8)), direct enzymatic oxidation of the resultant 2-arachidonoyl-lysophospholipids, and the esterification of oxidized 2-arachidonoyl-lysophospholipids by acyl-CoA-dependent sn-1 acyltransferase(s). To circumvent ambiguities associated with acyl migration or hydrolysis, we developed a synthesis for optically active (d- and l-enantiomers) nonhydrolyzable analogs of 2-arachidonoyl-lysophosphatidylcholine (2-AA-LPC). sn-1 acyltransferase activity in murine liver microsomes stereospecifically and preferentially utilized the naturally occurring l-enantiomer of the ether analog of lysophosphatidylcholine. Next, we demonstrated the high selectivity of the sn-1 acyltransferase activity for saturated acyl-CoA species. Importantly, we established that 2-15-hydroxyeicosatetraenoic acid (HETE) ether-LPC sn-1 esterification is markedly activated by thrombin treatment of murine platelets to generate oxidized PC. Collectively, these findings demonstrate the enantiomeric specificity and saturated acyl-CoA selectivity of microsomal sn-1 acyltransferase(s) and reveal its participation in a previously uncharacterized pathway for the synthesis of oxidized phospholipids with cell-signaling properties.
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Affiliation(s)
- Gao-Yuan Liu
- From the Department of Chemistry, Washington University, Saint Louis, Missouri 63130 and.,Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine
| | - Sung Ho Moon
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine
| | | | - Harold F Sims
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine
| | - Shaoping Guan
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine
| | - Richard W Gross
- From the Department of Chemistry, Washington University, Saint Louis, Missouri 63130 and .,Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine.,Developmental Biology, and.,Center for Cardiovascular Research, Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri 63110
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21
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The Impact of Cardiac Lipotoxicity on Cardiac Function and Mirnas Signature in Obese and Non-Obese Rats with Myocardial Infarction. Sci Rep 2019; 9:444. [PMID: 30679580 PMCID: PMC6345821 DOI: 10.1038/s41598-018-36914-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 11/27/2018] [Indexed: 02/08/2023] Open
Abstract
Cardiac lipotoxicity is involved in the cardiac functional consequences associated with obesity. Therefore, the aim of this study was to explore whether changes in the mitochondrial lipid cardiac profile could reflect differences in cardiac function and structure in obese and non-obese rats with myocardial infarction (MI). Whether these changes can also be reflected in a specific plasma miRNA signature as markers of cardiac damage was also evaluated. Rats were fed with either standard (3.5% fat) or high fat diet (35% fat) for 6 weeks before the induction of MI and sacrificed 4 weeks later. MI showed cardiac lipotoxicity independently of the presence of obesity, although obese and non-obese rats did not present the same cardiac lipid profile at mitochondrial level. Several cardiac lipid species in mitochondria, including cardiolipins and triglycerides, were associated with myocardial fibrosis, with mitochondrial triglyceride levels being independently associated with it; this supports that lipotoxicity can affect cardiac function. MI down-regulated plasma levels of miRNA 15b-5p and 194-5p in obese and non-obese animals, which were associated with cardiac function, mitochondrial lipids and myocardial fibrosis, with miRNA 15b-5p levels being independently associated with cardiac fibrosis. This could support that lipotoxicity could affect heart function by modulating plasma miRNAs.
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22
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Sato T, Segawa M, Sekine S, Ito K. Mild depolarization is involved in troglitazone-induced liver mitochondrial membrane permeability transition via mitochondrial iPLA 2 activation. J Toxicol Sci 2019; 44:811-820. [DOI: 10.2131/jts.44.811] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Tomoyuki Sato
- The Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University
| | - Masahiro Segawa
- The Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University
| | - Shuichi Sekine
- The Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University
| | - Kousei Ito
- The Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University
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23
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Turk J, White TD, Nelson AJ, Lei X, Ramanadham S. iPLA 2β and its role in male fertility, neurological disorders, metabolic disorders, and inflammation. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:846-860. [PMID: 30408523 DOI: 10.1016/j.bbalip.2018.10.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Revised: 10/26/2018] [Accepted: 10/29/2018] [Indexed: 02/06/2023]
Abstract
The Ca2+-independent phospholipases, designated as group VI iPLA2s, also referred to as PNPLAs due to their shared homology with patatin, include the β, γ, δ, ε, ζ, and η forms of the enzyme. The iPLA2s are ubiquitously expressed, share a consensus GXSXG catalytic motif, and exhibit organelle/cell-specific localization. Among the iPLA2s, iPLA2β has received wide attention as it is recognized to be involved in membrane remodeling, cell proliferation, cell death, and signal transduction. Ongoing studies implicate participation of iPLA2β in a variety of disease processes including cancer, cardiovascular abnormalities, glaucoma, and peridonditis. This review will focus on iPLA2β and its links to male fertility, neurological disorders, metabolic disorders, and inflammation.
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Affiliation(s)
- John Turk
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, United States of America
| | - Tayleur D White
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States of America; Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL, United States of America
| | - Alexander J Nelson
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States of America; Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL, United States of America
| | - Xiaoyong Lei
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States of America; Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL, United States of America
| | - Sasanka Ramanadham
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, United States of America; Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL, United States of America.
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24
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Chao H, Anthonymuthu TS, Kenny EM, Amoscato AA, Cole LK, Hatch GM, Ji J, Kagan VE, Bayır H. Disentangling oxidation/hydrolysis reactions of brain mitochondrial cardiolipins in pathogenesis of traumatic injury. JCI Insight 2018; 3:97677. [PMID: 30385716 DOI: 10.1172/jci.insight.97677] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 09/19/2018] [Indexed: 01/05/2023] Open
Abstract
Mechanical injury to the brain triggers multiple biochemical events whose specific contributions to the pathogenesis define clinical manifestations and the overall outcome. Among many factors, mitochondrial injury has recently attracted much attention due to the importance of the organelle for bioenergetics as well as intra- and extracellular signaling and cell death. Assuming the essentiality of a mitochondria-unique phospholipid, cardiolipin (CL), for the structural and functional organization of mitochondria, here we applied global (phospho) lipidomics and redox lipidomics to reveal and identify CL modifications during controlled cortical impact (CCI). We revealed 2 major pathways activated in the CCI-injured brain as time-specific responses: early accumulation of oxidized CL (CLox) products was followed by hydrolytic reactions yielding monolyso-CLs (mCLs) and free fatty acids. To quantitatively assess possible specific roles of peroxidation and hydrolysis of mitochondrial CL, we performed comparative studies of CL modifications using an animal model of Barth syndrome where deficiency of CL reacylation (Tafazzin [Taz] deficiency) was associated exclusively with the accumulation of mCLs (but not CLox). By comparing the in vitro and in vivo results with genetic manipulation of major CL-, CLox-, and mCL-metabolizing enzymes, calcium-independent phospholipase A2γ and Taz, we concluded that the 2 processes - CL oxidation and CL hydrolysis - act as mutually synergistically enhancing components of the pathogenic mechanism of mitochondrial injury in traumatic brain injury. This emphasizes the need for combined therapeutic approaches preventing the formation of both CLox and mCL.
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Affiliation(s)
- Honglu Chao
- The Safar Center for Resuscitation Research and the Neuroscience Institute of Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.,Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Tamil S Anthonymuthu
- The Safar Center for Resuscitation Research and the Neuroscience Institute of Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.,Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Elizabeth M Kenny
- The Safar Center for Resuscitation Research and the Neuroscience Institute of Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.,Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Andrew A Amoscato
- Center for Free Radical and Antioxidant Health, Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Laura K Cole
- Diabetes Research Envisioned and Accomplished in Manitoba, Children's Hospital Research Institute of Manitoba, Department of Pharmacology and Therapeutics, Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada
| | - Grant M Hatch
- Diabetes Research Envisioned and Accomplished in Manitoba, Children's Hospital Research Institute of Manitoba, Department of Pharmacology and Therapeutics, Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada
| | - Jing Ji
- The Safar Center for Resuscitation Research and the Neuroscience Institute of Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.,Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Valerian E Kagan
- Center for Free Radical and Antioxidant Health, Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Laboratory of Navigational Redox Lipidomics, Institute of Regenerative Medicine, IM Sechenov Moscow State Medical University, Moscow, Russia
| | - Hülya Bayır
- The Safar Center for Resuscitation Research and the Neuroscience Institute of Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.,Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Diabetes Research Envisioned and Accomplished in Manitoba, Children's Hospital Research Institute of Manitoba, Department of Pharmacology and Therapeutics, Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada
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25
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Hara S, Yoda E, Sasaki Y, Nakatani Y, Kuwata H. Calcium-independent phospholipase A 2γ (iPLA 2γ) and its roles in cellular functions and diseases. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:861-868. [PMID: 30391710 DOI: 10.1016/j.bbalip.2018.10.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 10/25/2018] [Accepted: 10/26/2018] [Indexed: 12/18/2022]
Abstract
Calcium-independent phospholipase A2γ (iPLA2γ)/patatin-like phospholipase domain-containing lipase 8 (PNPLA8) is one of the iPLA2 enzymes, which do not require Ca2+ ion for their activity. iPLA2γ is a membrane-bound enzyme with unique features, including the utilization of four distinct translation initiation sites and the presence of mitochondrial and peroxisomal localization signals. This enzyme is preferentially distributed in the mitochondria and peroxisomes and is thought to be responsible for the maintenance of lipid homeostasis in these organelles. Thus, both the overexpression and the deletion of iPLA2γ in vivo caused mitochondrial abnormalities and dysfunction. Roles of iPLA2γ in lipid mediator production and cytoprotection against oxidative stress have also been suggested by in vitro and in vivo studies. The dysregulation of iPLA2γ can therefore be a critical factor in the development of many diseases, including metabolic diseases and cancer. In this review, we provide an overview of the biochemical properties of iPLA2γ and then summarize the current understanding of the in vivo roles of iPLA2γ revealed by knockout mouse studies.
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Affiliation(s)
- Shuntaro Hara
- Division of Health Chemistry, Department of Healthcare and Regulatory Sciences, School of Pharmacy, Showa University, Tokyo 142-8555, Japan.
| | - Emiko Yoda
- Division of Health Chemistry, Department of Healthcare and Regulatory Sciences, School of Pharmacy, Showa University, Tokyo 142-8555, Japan
| | - Yuka Sasaki
- Division of Health Chemistry, Department of Healthcare and Regulatory Sciences, School of Pharmacy, Showa University, Tokyo 142-8555, Japan
| | - Yoshihito Nakatani
- Division of Health Chemistry, Department of Healthcare and Regulatory Sciences, School of Pharmacy, Showa University, Tokyo 142-8555, Japan
| | - Hiroshi Kuwata
- Division of Health Chemistry, Department of Healthcare and Regulatory Sciences, School of Pharmacy, Showa University, Tokyo 142-8555, Japan
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26
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Jenkins CM, Yang K, Liu G, Moon SH, Dilthey BG, Gross RW. Cytochrome c is an oxidative stress-activated plasmalogenase that cleaves plasmenylcholine and plasmenylethanolamine at the sn-1 vinyl ether linkage. J Biol Chem 2018. [PMID: 29530984 DOI: 10.1074/jbc.ra117.001629] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Plasmalogens are phospholipids critical for cell function and signaling that contain a vinyl ether linkage at the sn-1 position and are highly enriched in arachidonic acid (AA) at the sn-2 position. However, the enzyme(s) responsible for the cleavage of the vinyl ether linkage in plasmalogens has remained elusive. Herein, we report that cytochrome c, in the presence of either cardiolipin (CL), O2 and H2O2, or oxidized CL and O2, catalyzes the oxidation of the plasmalogen vinyl ether linkage, promoting its hydrolytic cleavage and resultant production of 2-AA-lysolipids and highly reactive α-hydroxy fatty aldehydes. Using stable isotope labeling in synergy with strategic chemical derivatizations and high-mass-accuracy MS, we deduced the chemical mechanism underlying this long sought-after reaction. Specifically, labeling with either 18O2 or H218O, but not with H218O2, resulted in M + 2 isotopologues of the α-hydroxyaldehyde, whereas reactions with both 18O2 and H218O identified the M + 4 isotopologue. Furthermore, incorporation of 18O from 18O2 was predominantly located at the α-carbon. In contrast, reactions with H218O yielded 18O linked to the aldehyde carbon. Importantly, no significant labeling of 2-AA-lysolipids with 18O2, H218O, or H218O2 was present. Intriguingly, phosphatidylinositol phosphates (PIP2 and PIP3) effectively substituted for cardiolipin. Moreover, cytochrome c released from myocardial mitochondria subjected to oxidative stress cleaved plasmenylcholine in membrane bilayers, and this was blocked with a specific mAb against cytochrome c Collectively, these results identify the first plasmalogenase in biology, reveal the production of previously unanticipated signaling lipids by cytochrome c, and present new perspectives on cellular signaling during oxidative stress.
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Affiliation(s)
- Christopher M Jenkins
- From the Division of Bioorganic Chemistry and Molecular Pharmacology and.,Departments of Medicine and
| | - Kui Yang
- From the Division of Bioorganic Chemistry and Molecular Pharmacology and
| | - Gaoyuan Liu
- From the Division of Bioorganic Chemistry and Molecular Pharmacology and.,Departments of Medicine and.,the Department of Chemistry, Washington University, St. Louis, Missouri 63130
| | - Sung Ho Moon
- From the Division of Bioorganic Chemistry and Molecular Pharmacology and.,Departments of Medicine and
| | - Beverly G Dilthey
- From the Division of Bioorganic Chemistry and Molecular Pharmacology and.,Departments of Medicine and
| | - Richard W Gross
- From the Division of Bioorganic Chemistry and Molecular Pharmacology and .,Departments of Medicine and.,the Department of Chemistry, Washington University, St. Louis, Missouri 63130.,Developmental Biology, Washington University School of Medicine, St. Louis, Missouri 63110 and
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27
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Yao CH, Liu GY, Wang R, Moon SH, Gross RW, Patti GJ. Identifying off-target effects of etomoxir reveals that carnitine palmitoyltransferase I is essential for cancer cell proliferation independent of β-oxidation. PLoS Biol 2018; 16:e2003782. [PMID: 29596410 PMCID: PMC5892939 DOI: 10.1371/journal.pbio.2003782] [Citation(s) in RCA: 130] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Revised: 04/10/2018] [Accepted: 02/22/2018] [Indexed: 02/06/2023] Open
Abstract
It has been suggested that some cancer cells rely upon fatty acid oxidation (FAO) for energy. Here we show that when FAO was reduced approximately 90% by pharmacological inhibition of carnitine palmitoyltransferase I (CPT1) with low concentrations of etomoxir, the proliferation rate of various cancer cells was unaffected. Efforts to pharmacologically inhibit FAO more than 90% revealed that high concentrations of etomoxir (200 μM) have an off-target effect of inhibiting complex I of the electron transport chain. Surprisingly, however, when FAO was reduced further by genetic knockdown of CPT1, the proliferation rate of these same cells decreased nearly 2-fold and could not be restored by acetate or octanoic acid supplementation. Moreover, CPT1 knockdowns had altered mitochondrial morphology and impaired mitochondrial coupling, whereas cells in which CPT1 had been approximately 90% inhibited by etomoxir did not. Lipidomic profiling of mitochondria isolated from CPT1 knockdowns showed depleted concentrations of complex structural and signaling lipids. Additionally, expression of a catalytically dead CPT1 in CPT1 knockdowns did not restore mitochondrial coupling. Taken together, these results suggest that transport of at least some long-chain fatty acids into the mitochondria by CPT1 may be required for anabolic processes that support healthy mitochondrial function and cancer cell proliferation independent of FAO.
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Affiliation(s)
- Cong-Hui Yao
- Department of Chemistry, Washington University, St. Louis, Missouri, United States of America
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Gao-Yuan Liu
- Department of Chemistry, Washington University, St. Louis, Missouri, United States of America
- Department of Internal Medicine, Division of Bioorganic and Molecular Pharmacology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Rencheng Wang
- Department of Chemistry, Washington University, St. Louis, Missouri, United States of America
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Sung Ho Moon
- Department of Chemistry, Washington University, St. Louis, Missouri, United States of America
- Department of Internal Medicine, Division of Bioorganic and Molecular Pharmacology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Richard W. Gross
- Department of Chemistry, Washington University, St. Louis, Missouri, United States of America
- Department of Internal Medicine, Division of Bioorganic and Molecular Pharmacology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Gary J. Patti
- Department of Chemistry, Washington University, St. Louis, Missouri, United States of America
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
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28
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Lowered iPLA2γ activity causes increased mitochondrial lipid peroxidation and mitochondrial dysfunction in a rotenone-induced model of Parkinson's disease. Exp Neurol 2018; 300:74-86. [DOI: 10.1016/j.expneurol.2017.10.031] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 10/26/2017] [Accepted: 10/30/2017] [Indexed: 12/25/2022]
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Abstract
A decade of research has established the phospholipase iPLA2γ as being involved in cardiomyocyte dysfunction and necrosis leading to heart failure, but the mechanisms by which iPLA2γ acts and its interaction with the mitochondrial permeability transition pore (mPTP) that is critical for cardiac homeostasis are unclear. New investigations by Moon et al. demonstrate that mitochondria in failing hearts undergo dynamic shifts in PLA2 isoform expression, leading to a redistribution of eicosanoid composition that contributes to pathologic mPTP opening.
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Affiliation(s)
- Matthew J Wolf
- Division of Cardiovascular Medicine, Department of Medicine, The University of Virginia School of Medicine, Charlottesville, Virginia 22908.
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30
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Moon SH, Liu X, Cedars AM, Yang K, Kiebish MA, Joseph SM, Kelley J, Jenkins CM, Gross RW. Heart failure-induced activation of phospholipase iPLA 2γ generates hydroxyeicosatetraenoic acids opening the mitochondrial permeability transition pore. J Biol Chem 2017; 293:115-129. [PMID: 29158256 DOI: 10.1074/jbc.ra117.000405] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 11/08/2017] [Indexed: 11/06/2022] Open
Abstract
Congestive heart failure typically arises from cardiac myocyte necrosis/apoptosis, associated with the pathological opening of the mitochondrial permeability transition pore (mPTP). mPTP opening decreases the mitochondrial membrane potential leading to the activation of Ca2+-independent phospholipase A2γ (iPLA2γ) and the production of downstream toxic metabolites. However, the array of enzymatic mediators and the exact chemical mechanisms responsible for modulating myocardial mPTP opening remain unclear. Herein, we demonstrate that human heart failure activates specific myocardial mitochondrial phospholipases that increase Ca2+-dependent production of toxic hydroxyeicosatetraenoic acids (HETEs) and attenuate the activity of phospholipases that promote the synthesis of protective epoxyeicosatrienoic acids (EETs). Mechanistically, HETEs activated the Ca2+-induced opening of the mPTP in failing human myocardium, and the highly selective pharmacological blockade of either iPLA2γ or lipoxygenases attenuated mPTP opening in failing hearts. In contrast, pharmacological inhibition of cytochrome P450 epoxygenases opened the myocardial mPTP in human heart mitochondria. Remarkably, the major mitochondrial phospholipase responsible for Ca2+-activated release of arachidonic acid (AA) in mitochondria from non-failing hearts was calcium-dependent phospholipase A2ζ (cPLA2ζ) identified by sequential column chromatographies and activity-based protein profiling. In contrast, iPLA2γ predominated in failing human myocardium. Stable isotope kinetics revealed that in non-failing human hearts, cPLA2ζ metabolically channels arachidonic acid into EETs, whereas in failing hearts, increased iPLA2γ activity channels AA into toxic HETEs. These results mechanistically identify the sequelae of pathological remodeling of human mitochondrial phospholipases in failing myocardium. This remodeling metabolically channels AA into toxic HETEs promoting mPTP opening, which induces necrosis/apoptosis leading to further progression of heart failure.
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Affiliation(s)
- Sung Ho Moon
- Division of Bioorganic Chemistry and Molecular Pharmacology, the Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Xinping Liu
- Division of Bioorganic Chemistry and Molecular Pharmacology, the Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Ari M Cedars
- Division of Bioorganic Chemistry and Molecular Pharmacology, the Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Kui Yang
- Division of Bioorganic Chemistry and Molecular Pharmacology, the Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Michael A Kiebish
- Division of Bioorganic Chemistry and Molecular Pharmacology, the Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Susan M Joseph
- Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - John Kelley
- Division of Bioorganic Chemistry and Molecular Pharmacology, the Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Christopher M Jenkins
- Division of Bioorganic Chemistry and Molecular Pharmacology, the Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Richard W Gross
- Division of Bioorganic Chemistry and Molecular Pharmacology, the Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110; Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri 63110; Center for Cardiovascular Research, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110; Department of Chemistry, Washington University, St. Louis, Missouri 63130.
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31
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Huang Z, Jiang H, Cui X, Liang G, Chen Y, Wang T, Sun Z, Qi L. Elevated serum levels of lipoprotein‑associated phospholipase A2 predict mortality rates in patients with sepsis. Mol Med Rep 2017; 17:1791-1798. [PMID: 29138849 DOI: 10.3892/mmr.2017.8034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 01/09/2017] [Indexed: 11/06/2022] Open
Abstract
Sepsis remains one of the leading contributors to mortality rates in the intensive care unit (ICU) and emergency intensive care unit (EICU). Therefore, any treatments against the agents which produce sepsis in a medical emergency, are welcome. Elevated serum levels of lipoprotein‑associated phospholipase A2 (Lp‑PLA2) have been reported in a small cohort of patients with inflammation. The present study evaluated serum levels of Lp‑PLA2 in patients with sepsis and investigated the role of Lp‑PLA2 in sepsis. The investigation involved the selection of 151 patients with sepsis admitted to the emergency department of the Affiliated Hospital of Nantong University (Nantong, China) and 30 healthy controls. All patients (39 with sepsis, 55 with severe sepsis and 57 with septic shock) were examined on admission to the EICU. A complete blood count was performed, and serum levels of Lp‑PLA2, C‑reactive protein, procalcitonin, and interleukin 6, sequential organ failure (SOFA) scores and Acute Physiology and Chronic Health Evaluation II (APACHE II) scores were determined on hospital admission. The EICU and overall mortality rates were evaluated at baseline. The present study also assessed various laboratory parameters, clinical data and inflammatory cytokines. The patient follow up duration was 90 days. The data suggested that the serum levels of Lp‑PLA2 on admission to the EICU in patients with sepsis were elevated, compared with those in healthy controls. The concentrations of Lp‑PLA2 were correlated with the severity of disease, and were significantly associated with experimental markers of inflammation and established prognostic scores. In the total cohort, persistently elevated levels of Lp‑PLA2 on admission for EICU treatment was a predictor of poor prognosis, and provided superior diagnostic use, compared with the prognostic scoring systems, including SOFA or APACHE II scores. Taken together, the results suggested that Lp‑PLA2, with respect to other markers of inflammation, may have a role as a prognostic marker in sepsis, and provide background evidence for further trials to evaluate the clinical and pathophysiologic roles of Lp‑PLA2 in sepsis. Persistently elevated serum concentrations of Lp‑PLA2 indicated an unfavorable outcome in patients with sepsis. In addition, the results indicated the potential role of Lp‑PLA2 as a prognostic biomarker in patients with sepsis during the early course of EICU treatment.
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Affiliation(s)
- Zhongwei Huang
- Department of Emergency Medicine, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Haiyan Jiang
- Department of Emergency Medicine, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Xiaohui Cui
- Department of Emergency Medicine, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Guiwen Liang
- Department of Geriatric Medicine, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Yu Chen
- Department of Emergency Medicine, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Ting Wang
- Department of Emergency Medicine, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Zhichao Sun
- Medical College, Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Lei Qi
- Department of Emergency Medicine, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, P.R. China
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Xiao M, Zhong H, Xia L, Tao Y, Yin H. Pathophysiology of mitochondrial lipid oxidation: Role of 4-hydroxynonenal (4-HNE) and other bioactive lipids in mitochondria. Free Radic Biol Med 2017; 111:316-327. [PMID: 28456642 DOI: 10.1016/j.freeradbiomed.2017.04.363] [Citation(s) in RCA: 138] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 04/21/2017] [Accepted: 04/24/2017] [Indexed: 02/06/2023]
Abstract
Mitochondrial lipids are essential for maintaining the integrity of mitochondrial membranes and the proper functions of mitochondria. As the "powerhouse" of a cell, mitochondria are also the major cellular source of reactive oxygen species (ROS). Oxidative stress occurs when the antioxidant system is overwhelmed by overproduction of ROS. Polyunsaturated fatty acids in mitochondrial membranes are primary targets for ROS attack, which may lead to lipid peroxidation (LPO) and generation of reactive lipids, such as 4-hydroxynonenal. When mitochondrial lipids are oxidized, the integrity and function of mitochondria may be compromised and this may eventually lead to mitochondrial dysfunction, which has been associated with many human diseases including cancer, cardiovascular diseases, diabetes, and neurodegenerative diseases. How mitochondrial lipids are oxidized and the underlying molecular mechanisms and pathophysiological consequences associated with mitochondrial LPO remain poorly defined. Oxidation of the mitochondria-specific phospholipid cardiolipin and generation of bioactive lipids through mitochondrial LPO has been increasingly recognized as an important event orchestrating apoptosis, metabolic reprogramming of energy production, mitophagy, and immune responses. In this review, we focus on the current understanding of how mitochondrial LPO and generation of bioactive lipid mediators in mitochondria are involved in the modulation of mitochondrial functions in the context of relevant human diseases associated with oxidative stress.
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Affiliation(s)
- Mengqing Xiao
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences (INS), Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS), Shanghai, China; School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Huiqin Zhong
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China; University of the Chinese Academy of Sciences, CAS, Beijing, China
| | - Lin Xia
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences (INS), Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS), Shanghai, China; Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing, China
| | - Yongzhen Tao
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences (INS), Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS), Shanghai, China; Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing, China
| | - Huiyong Yin
- Key Laboratory of Food Safety Research, Institute for Nutritional Sciences (INS), Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS), Shanghai, China; School of Life Science and Technology, ShanghaiTech University, Shanghai, China; University of the Chinese Academy of Sciences, CAS, Beijing, China; Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing, China.
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Ravindran S, Kurian GA. The role of secretory phospholipases as therapeutic targets for the treatment of myocardial ischemia reperfusion injury. Biomed Pharmacother 2017; 92:7-16. [DOI: 10.1016/j.biopha.2017.05.042] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Revised: 04/27/2017] [Accepted: 05/08/2017] [Indexed: 01/22/2023] Open
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Kispert S, Schwartz T, McHowat J. Cigarette Smoke Regulates Calcium-Independent Phospholipase A2 Metabolic Pathways in Breast Cancer. THE AMERICAN JOURNAL OF PATHOLOGY 2017; 187:1855-1866. [DOI: 10.1016/j.ajpath.2017.04.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Revised: 03/24/2017] [Accepted: 04/04/2017] [Indexed: 11/25/2022]
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Liu GY, Moon SH, Jenkins CM, Li M, Sims HF, Guan S, Gross RW. The phospholipase iPLA 2γ is a major mediator releasing oxidized aliphatic chains from cardiolipin, integrating mitochondrial bioenergetics and signaling. J Biol Chem 2017; 292:10672-10684. [PMID: 28442572 DOI: 10.1074/jbc.m117.783068] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 04/24/2017] [Indexed: 01/08/2023] Open
Abstract
Cardiolipin (CL) is a dimeric phospholipid with critical roles in mitochondrial bioenergetics and signaling. Recently, inhibition of the release of oxidized fatty acyl chains from CL by the calcium-independent phospholipase A2γ (iPLA2γ)-selective inhibitor (R)-BEL suggested that iPLA2γ is responsible for the hydrolysis of oxidized CL and subsequent signaling mediated by the released oxidized fatty acids. However, chemical inhibition by BEL is subject to off-target pharmacologic effects. Accordingly, to unambiguously determine the role of iPLA2γ in the hydrolysis of oxidized CL, we compared alterations in oxidized CLs and the release of oxidized aliphatic chains from CL in experiments with purified recombinant iPLA2γ, germ-line iPLA2γ-/- mice, cardiac myocyte-specific iPLA2γ transgenic mice, and wild-type mice. Using charge-switch high mass accuracy LC-MS/MS with selected reaction monitoring and product ion accurate masses, we demonstrated that iPLA2γ is the major enzyme responsible for the release of oxidized aliphatic chains from CL. Our results also indicated that iPLA2γ selectively hydrolyzes 9-hydroxy-octadecenoic acid in comparison to 13-hydroxy-octadecenoic acid from oxidized CLs. Moreover, oxidative stress (ADP, NADPH, and Fe3+) resulted in the robust production of oxidized CLs in intact mitochondria from iPLA2γ-/- mice. In sharp contrast, oxidized CLs were readily hydrolyzed in mitochondria from wild-type mice during oxidative stress. Finally, we demonstrated that CL activates the iPLA2γ-mediated hydrolysis of arachidonic acid from phosphatidylcholine, thereby integrating the production of lipid messengers from different lipid classes in mitochondria. Collectively, these results demonstrate the integrated roles of CL and iPLA2γ in lipid second-messenger production and mitochondrial bioenergetics during oxidative stress.
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Affiliation(s)
- Gao-Yuan Liu
- From the Department of Chemistry, Washington University, Saint Louis, Missouri 63130 and
| | - Sung Ho Moon
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine
| | | | - Maoyin Li
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine
| | - Harold F Sims
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine
| | - Shaoping Guan
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine
| | - Richard W Gross
- From the Department of Chemistry, Washington University, Saint Louis, Missouri 63130 and .,Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine.,Department of Developmental Biology, and.,Center for Cardiovascular Research, Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri 63110
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MURAKAMI M. Lipoquality control by phospholipase A 2 enzymes. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2017; 93:677-702. [PMID: 29129849 PMCID: PMC5743847 DOI: 10.2183/pjab.93.043] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The phospholipase A2 (PLA2) family comprises a group of lipolytic enzymes that typically hydrolyze the sn-2 position of glycerophospholipids to give rise to fatty acids and lysophospholipids. The mammalian genome encodes more than 50 PLA2s or related enzymes, which are classified into several subfamilies on the basis of their structures and functions. From a general viewpoint, the PLA2 family has mainly been implicated in signal transduction, producing bioactive lipid mediators derived from fatty acids and lysophospholipids. Recent evidence indicates that PLA2s also contribute to phospholipid remodeling for membrane homeostasis or energy production for fatty acid β-oxidation. Accordingly, PLA2 enzymes can be regarded as one of the key regulators of the quality of lipids, which I herein refer to as lipoquality. Disturbance of PLA2-regulated lipoquality hampers tissue and cellular homeostasis and can be linked to various diseases. Here I overview the current state of understanding of the classification, enzymatic properties, and physiological functions of the PLA2 family.
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Affiliation(s)
- Makoto MURAKAMI
- Laboratory of Environmental and Metabolic Health Sciences, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, the University of Tokyo, Tokyo, Japan
- Lipid Metabolism Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
- AMED-CREST, Japan Agency for Medical Research and Development, Tokyo, Japan
- Correspondence should be addressed: M. Murakami, Laboratory of Environmental and Metabolic Health Sciences, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan (e-mail: )
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Leskova GF. Phospholipids in mitochondrial dysfunction during hemorrhagic shock. J Bioenerg Biomembr 2016; 49:121-129. [PMID: 27999981 DOI: 10.1007/s10863-016-9691-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 12/05/2016] [Indexed: 01/04/2023]
Abstract
Energy deficiency plays a key role in the development of irreversible shock conditions. Therefore, identifying mitochondrial functional disturbances during hemorrhagic shock should be considered a prospective direction for studying its pathogenesis. Phospholipid (PL)-dependent mechanisms of mitochondrial dysfunction in the brain (i.e., in the frontal lobes of the cerebral hemispheres and medulla oblongata) and liver, which, when damaged, leads to an encephalopathy, are examined in this review. These mechanisms show strong regional specificity. Analyzing the data presented in this review suggests that the basis for mitochondrial functional disturbances is cholinergic hyperactivation, accompanied by a choline deficiency and membrane phosphatidylcholine (PC) depletion. Stabilization of the PL composition in mitochondrial membranes using "empty" PC liposomes could be one of the most important methods for eliminating energy deficiency during massive blood loss.
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Affiliation(s)
- Galina F Leskova
- Laboratory of nanopathology and biomedical nanotechnologies, Institute of General Pathology und Pathophysiology, Baltijskaja str., 8, 125315, Moscow, Russia.
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SREBP-2/PNPLA8 axis improves non-alcoholic fatty liver disease through activation of autophagy. Sci Rep 2016; 6:35732. [PMID: 27767079 PMCID: PMC5073315 DOI: 10.1038/srep35732] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 10/03/2016] [Indexed: 01/04/2023] Open
Abstract
Dysregulated autophagy is associated with steatosis and non-alcoholic fatty liver disease (NAFLD), however the mechanisms connecting them remain poorly understand. Here, we show that co-administration of lovastatin and ezetimibe (L/E) significantly reverses hepatic triglyceride accumulation concomitant with an increase in SREBP-2 driven autophagy in mice fed a high-fat diet (HFD). We further show that the statin mediated increase in SREBP-2 directly activates expression of patatin-like phospholipase domain-containing enzyme 8 (PNPLA8) gene, and PNPLA8 associates with autophagosomes and is associated with a decrease in cellular triglyceride. Moreover, we show that over-expression of PNPLA8 dramatically decreases hepatic steatosis through increased autophagy in hepatocytes of HFD-fed mice. Live-cell imaging analyses also reveal that PNPLA8 dynamically interacts with LC3 and we suggest that the SREBP-2/PNPLA8 axis represents a novel regulatory mechanism for lipid homeostasis. These data provide a possible mechanism for the reported beneficial effects of statins for decreasing hepatic triglyceride levels in NAFLD patients.
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Liu X, Moon SH, Jenkins CM, Sims HF, Gross RW. Cyclooxygenase-2 Mediated Oxidation of 2-Arachidonoyl-Lysophospholipids Identifies Unknown Lipid Signaling Pathways. Cell Chem Biol 2016; 23:1217-1227. [PMID: 27642067 DOI: 10.1016/j.chembiol.2016.08.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 07/27/2016] [Accepted: 08/02/2016] [Indexed: 12/27/2022]
Abstract
Eicosanoid lipids play important roles in cellular signaling as second messengers in inflammation, immune response, vascular tone, and the CNS. Biosynthesis of eicosanoid lipids proceeds via hydrolysis of esterified arachidonic acid from phospholipids followed by oxidation of the released arachidonic acid by a variety of enzymes including cyclooxygenases (COX). Herein, we demonstrate the remarkable ability of COX-2, but not COX-1, to directly oxidize 2-arachidonoyl-lysolipids, resulting in the generation of previously unknown classes of eicosanoid-lysolipids, and provide evidence that intracellular lipases can release eicosanoids from their eicosanoid-lysolipid precursors. Importantly, genetic ablation of a phospholipase, iPLA2γ, significantly reduced the amounts of these eicosanoid-lysolipids in murine hepatic tissue and fibroblasts. Furthermore, calcium stimulation of wild-type murine lung fibroblasts produced robust increases in these eicosanoid-lysolipids, which were markedly attenuated in iPLA2γ-/- fibroblasts. Collectively, these results identify an iPLA2γ-initiated pathway generating new classes of lipid metabolites with potential signaling functions resulting from the direct COX-2 catalyzed oxidation of 2-arachidonoyl-lysolipids.
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Affiliation(s)
- Xinping Liu
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, 660 South Euclid Avenue, Campus Box 8020, Saint Louis, MO 63110, USA
| | - Sung Ho Moon
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, 660 South Euclid Avenue, Campus Box 8020, Saint Louis, MO 63110, USA
| | - Christopher M Jenkins
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, 660 South Euclid Avenue, Campus Box 8020, Saint Louis, MO 63110, USA
| | - Harold F Sims
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, 660 South Euclid Avenue, Campus Box 8020, Saint Louis, MO 63110, USA
| | - Richard W Gross
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Medicine, Washington University School of Medicine, 660 South Euclid Avenue, Campus Box 8020, Saint Louis, MO 63110, USA; Department of Developmental Biology, Washington University School of Medicine, Saint Louis, MO 63110, USA; Department of Chemistry, Washington University, Saint Louis, MO 63130, USA.
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Moon SH, Mancuso DJ, Sims HF, Liu X, Nguyen AL, Yang K, Guan S, Dilthey BG, Jenkins CM, Weinheimer CJ, Kovacs A, Abendschein D, Gross RW. Cardiac Myocyte-specific Knock-out of Calcium-independent Phospholipase A2γ (iPLA2γ) Decreases Oxidized Fatty Acids during Ischemia/Reperfusion and Reduces Infarct Size. J Biol Chem 2016; 291:19687-700. [PMID: 27453526 DOI: 10.1074/jbc.m116.740597] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Indexed: 12/21/2022] Open
Abstract
Calcium-independent phospholipase A2γ (iPLA2γ) is a mitochondrial enzyme that produces lipid second messengers that facilitate opening of the mitochondrial permeability transition pore (mPTP) and contribute to the production of oxidized fatty acids in myocardium. To specifically identify the roles of iPLA2γ in cardiac myocytes, we generated cardiac myocyte-specific iPLA2γ knock-out (CMiPLA2γKO) mice by removing the exon encoding the active site serine (Ser-477). Hearts of CMiPLA2γKO mice exhibited normal hemodynamic function, glycerophospholipid molecular species composition, and normal rates of mitochondrial respiration and ATP production. In contrast, CMiPLA2γKO mice demonstrated attenuated Ca(2+)-induced mPTP opening that could be rapidly restored by the addition of palmitate and substantially reduced production of oxidized polyunsaturated fatty acids (PUFAs). Furthermore, myocardial ischemia/reperfusion (I/R) in CMiPLA2γKO mice (30 min of ischemia followed by 30 min of reperfusion in vivo) dramatically decreased oxidized fatty acid production in the ischemic border zones. Moreover, CMiPLA2γKO mice subjected to 30 min of ischemia followed by 24 h of reperfusion in vivo developed substantially less cardiac necrosis in the area-at-risk in comparison with their WT littermates. Furthermore, we found that membrane depolarization in murine heart mitochondria was sensitized to Ca(2+) by the presence of oxidized PUFAs. Because mitochondrial membrane depolarization and calcium are known to activate iPLA2γ, these results are consistent with salvage of myocardium after I/R by iPLA2γ loss of function through decreasing mPTP opening, diminishing production of proinflammatory oxidized fatty acids, and attenuating the deleterious effects of abrupt increases in calcium ion on membrane potential during reperfusion.
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Affiliation(s)
- Sung Ho Moon
- From the Division of Bioorganic Chemistry and Molecular Pharmacology, Departments of Medicine
| | - David J Mancuso
- From the Division of Bioorganic Chemistry and Molecular Pharmacology, Departments of Medicine
| | - Harold F Sims
- From the Division of Bioorganic Chemistry and Molecular Pharmacology, Departments of Medicine
| | - Xinping Liu
- From the Division of Bioorganic Chemistry and Molecular Pharmacology, Departments of Medicine
| | - Annie L Nguyen
- Center for Cardiovascular Research, Washington University School of Medicine, Saint Louis, Missouri 63110 and
| | - Kui Yang
- From the Division of Bioorganic Chemistry and Molecular Pharmacology, Departments of Medicine
| | - Shaoping Guan
- From the Division of Bioorganic Chemistry and Molecular Pharmacology, Departments of Medicine
| | - Beverly Gibson Dilthey
- From the Division of Bioorganic Chemistry and Molecular Pharmacology, Departments of Medicine
| | - Christopher M Jenkins
- From the Division of Bioorganic Chemistry and Molecular Pharmacology, Departments of Medicine
| | - Carla J Weinheimer
- Center for Cardiovascular Research, Washington University School of Medicine, Saint Louis, Missouri 63110 and
| | - Attila Kovacs
- Center for Cardiovascular Research, Washington University School of Medicine, Saint Louis, Missouri 63110 and
| | - Dana Abendschein
- Center for Cardiovascular Research, Washington University School of Medicine, Saint Louis, Missouri 63110 and
| | - Richard W Gross
- From the Division of Bioorganic Chemistry and Molecular Pharmacology, Departments of Medicine, Center for Cardiovascular Research, Washington University School of Medicine, Saint Louis, Missouri 63110 and Developmental Biology, and the Department of Chemistry, Washington University, Saint Louis, Missouri 63130
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Novel role of group VIB Ca2+-independent phospholipase A2γ in leukocyte-endothelial cell interactions: An intravital microscopic study in rat mesentery. J Trauma Acute Care Surg 2016; 79:782-9. [PMID: 26496102 DOI: 10.1097/ta.0000000000000845] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND Phospholipase A2 (PLA2) is associated with a variety of inflammatory processes related to polymorphonuclear neutrophil (PMN)-endothelial cell interactions. However, the cellular and molecular mechanisms underlying the interactions and the causative isoform(s) of PLA2 remain elusive. In addition, we recently showed that calcium-independent PLA2γ (iPLA2γ), but not cytosolic PLA2 (cPLA2), is responsible for the cytotoxic functions of human PMN including respiratory bursts, degranulation, and chemotaxis. We therefore hypothesized that iPLA2γ is a prerequisite for the PMN recruitment cascade into the site of inflammation. The aim of this study was to elucidate the roles of the three major phospholipases A2, iPLA2, cPLA2 and secretory PLA2, in leukocyte rolling and adherence and in the surface expression of β2-integrins in vivo and in vitro in response to well-defined stimuli. METHODS Male Wistar rats were pretreated with PLA2 inhibitors selective for iPLA2β, iPLA2γ, cPLA2, or secretory PLA2. Leukocyte rolling/adherence in the mesenteric venules superfused with platelet-activating factor (PAF) were quantified by intravital microscopy. Furthermore, isolated human PMNs or whole blood were incubated with each PLA2 inhibitor and then activated with formyl-methionyl-leucyl-phenylalanine (fMLP) or PAF. PMN adherence was assessed by counting cells bound to purified fibrinogen, and the surface expression of lymphocyte function-associated antigen 1 and macrophage antigen 1 (Mac-1) was measured by flow cytometry. RESULTS The iPLA2γ-specific inhibitor almost completely inhibited the fMLP/PAF-induced leukocyte adherence in vivo and in vitro and also decreased the fMLP/PAF-stimulated surface expression of Mac-1 by 60% and 95%, respectively. In contrast, the other inhibitors did not affect these cellular functions. CONCLUSION iPLA2γ seems to be involved in leukocyte/PMN adherence in vivo and in vitro as well as in the up-regulation of Mac-1 in vitro in response to PAF/fMLP. This enzyme is therefore likely to be a major regulator in the PMN recruitment cascade.
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Kunz E, Rothammer S, Pausch H, Schwarzenbacher H, Seefried FR, Matiasek K, Seichter D, Russ I, Fries R, Medugorac I. Confirmation of a non-synonymous SNP in PNPLA8 as a candidate causal mutation for Weaver syndrome in Brown Swiss cattle. Genet Sel Evol 2016; 48:21. [PMID: 26992691 PMCID: PMC4797220 DOI: 10.1186/s12711-016-0201-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 03/09/2016] [Indexed: 11/10/2022] Open
Abstract
Background Bovine progressive degenerative myeloencephalopathy (Weaver syndrome) is a neurodegenerative disorder in Brown Swiss cattle that is characterized by progressive hind leg weakness and ataxia, while sensorium and spinal reflexes remain unaffected. Although the causal mutation has not been identified yet, an indirect genetic test based on six microsatellite markers and consequent exclusion of Weaver carriers from breeding have led to the complete absence of new cases for over two decades. Evaluation of disease status by imputation of 41 diagnostic single nucleotide polymorphisms (SNPs) and a common haplotype published in 2013 identified several suspected carriers in the current breeding population, which suggests a higher frequency of the Weaver allele than anticipated. In order to prevent the reemergence of the disease, this study aimed at mapping the gene that underlies Weaver syndrome and thus at providing the basis for direct genetic testing and monitoring of today’s Braunvieh/Brown Swiss herds. Results Combined linkage/linkage disequilibrium mapping on Bos taurus chromosome (BTA) 4 based on Illumina Bovine SNP50 genotypes of 43 Weaver-affected, 31 Weaver carrier and 86 Weaver-free animals resulted in a maximum likelihood ratio test statistic value at position 49,812,384 bp. The confidence interval (0.853 Mb) determined by the 2-LOD drop-off method was contained within a 1.72-Mb segment of extended homozygosity. Exploitation of whole-genome sequence data from two official Weaver carriers and 1145 other bulls that were sequenced in Run4 of the 1000 bull genomes project showed that only a non-synonymous SNP (rs800397662) within the PNPLA8 gene at position 49,878,773 bp was concordant with the Weaver carrier status. Targeted SNP genotyping confirmed this SNP as a candidate causal mutation for Weaver syndrome. Genotyping for the candidate causal mutation in a random sample of 2334 current Braunvieh animals suggested a frequency of the Weaver allele of 0.26 %. Conclusions Through combined use of exhaustive sequencing data and SNP genotyping results, we were able to provide evidence that supports the non-synonymous mutation at position 49,878,773 bp as the most likely causal mutation for Weaver syndrome. Further studies are needed to uncover the exact mechanisms that underlie this syndrome. Electronic supplementary material The online version of this article (doi:10.1186/s12711-016-0201-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Elisabeth Kunz
- Chair of Animal Genetics and Husbandry, Ludwig-Maximilians-Universitaet Muenchen, Veterinaerstr. 13, 80539, Munich, Germany.,Tierzuchtforschung e.V. Muenchen, Senator-Gerauer-Str. 23, 85586, Poing, Germany
| | - Sophie Rothammer
- Chair of Animal Genetics and Husbandry, Ludwig-Maximilians-Universitaet Muenchen, Veterinaerstr. 13, 80539, Munich, Germany
| | - Hubert Pausch
- Chair of Animal Breeding, Technische Universitaet Muenchen, Liesel-Beckmann-Straße (Hochfeldweg) 1, 85354, Freising-Weihenstephan, Germany
| | | | | | - Kaspar Matiasek
- Institute of Veterinary Pathology, Ludwig-Maximilians-Universitaet Muenchen, Veterinaerstr. 13, 80539, Munich, Germany
| | - Doris Seichter
- Tierzuchtforschung e.V. Muenchen, Senator-Gerauer-Str. 23, 85586, Poing, Germany
| | - Ingolf Russ
- Tierzuchtforschung e.V. Muenchen, Senator-Gerauer-Str. 23, 85586, Poing, Germany
| | - Ruedi Fries
- Chair of Animal Breeding, Technische Universitaet Muenchen, Liesel-Beckmann-Straße (Hochfeldweg) 1, 85354, Freising-Weihenstephan, Germany
| | - Ivica Medugorac
- Chair of Animal Genetics and Husbandry, Ludwig-Maximilians-Universitaet Muenchen, Veterinaerstr. 13, 80539, Munich, Germany.
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43
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Saunders CJ, Moon SH, Liu X, Thiffault I, Coffman K, LePichon JB, Taboada E, Smith LD, Farrow EG, Miller N, Gibson M, Patterson M, Kingsmore SF, Gross RW. Loss of function variants in human PNPLA8 encoding calcium-independent phospholipase A2 γ recapitulate the mitochondriopathy of the homologous null mouse. Hum Mutat 2015; 36:301-6. [PMID: 25512002 DOI: 10.1002/humu.22743] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 12/09/2014] [Indexed: 12/13/2022]
Abstract
Mitochondriopathies are a group of clinically heterogeneous genetic diseases caused by defects in mitochondrial metabolism, bioenergetic efficiency, and/or signaling functions. The large majority of proteins involved in mitochondrial function are encoded by nuclear genes, with many yet to be associated with human disease. We performed exome sequencing on a young girl with a suspected mitochondrial myopathy that manifested as progressive muscle weakness, hypotonia, seizures, poor weight gain, and lactic acidosis. She was compound heterozygous for two frameshift mutations, p.Asn112HisfsX29 and p.Leu659AlafsX4, in the PNPLA8 gene, which encodes mitochondrial calcium-independent phospholipase A2 γ (iPLA2 γ). Western blot analysis of affected muscle displayed the absence of PNPLA8 protein. iPLA2 s are critical mediators of a variety of cellular processes including growth, metabolism, and lipid second messenger generation, exerting their functions through catalyzing the cleavage of the acyl groups in glycerophospholipids. The clinical presentation, muscle histology and the mitochondrial ultrastructural abnormalities of this proband are highly reminiscent of Pnpla8 null mice. Although other iPLA2 -related diseases have been identified, namely, infantile neuroaxonal dystrophy and neutral lipid storage disease with myopathy, this is the first report of PNPLA8-related disease in a human. We suggest PNPLA8 join the increasing list of human genes involved in lipid metabolism associated with neuromuscular diseases due to mitochondrial dysfunction.
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Affiliation(s)
- Carol J Saunders
- Center for Pediatric Genomic Medicine, Children's Mercy Hospitals, Kansas City, Missouri
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Kagan VE, Tyurina YY, Tyurin VA, Mohammadyani D, Angeli JPF, Baranov SV, Klein-Seetharaman J, Friedlander RM, Mallampalli RK, Conrad M, Bayir H. Cardiolipin signaling mechanisms: collapse of asymmetry and oxidation. Antioxid Redox Signal 2015; 22:1667-80. [PMID: 25566681 PMCID: PMC4486147 DOI: 10.1089/ars.2014.6219] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
SIGNIFICANCE An ancient anionic phospholipid, cardiolipin (CL), ubiquitously present in prokaryotic and eukaryotic membranes, is essential for several structural and functional purposes. RECENT ADVANCES The emerging role of CLs in signaling has become the focus of many studies. CRITICAL ISSUES In this work, we describe two major pathways through which mitochondrial CLs may fulfill the signaling functions via utilization of their (i) asymmetric distribution across membranes and translocations, leading to the surface externalization and (ii) ability to undergo oxidation reactions to yield the signature products recognizable by the executionary machinery of cells. FUTURE DIRECTIONS We present a concept that CLs and their oxidation/hydrolysis products constitute a rich communication language utilized by mitochondria of eukaryotic cells for diversified regulation of cell physiology and metabolism as well as for inter-cellular interactions.
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Affiliation(s)
- Valerian E Kagan
- 1Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania.,2Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania.,3Department of Radiation Oncology, University of Pittsburgh, Pittsburgh, Pennsylvania.,4Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Yulia Y Tyurina
- 1Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Vladimir A Tyurin
- 1Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Dariush Mohammadyani
- 5Department of Bioengineering, Acute Lung Injury Center of Excellence, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Jose Pedro Friedmann Angeli
- 6Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Neuherberg, Germany
| | - Sergei V Baranov
- 7Department of Neurosurgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Judith Klein-Seetharaman
- 8Division of Metabolic and Vascular Health, Medical School, University of Warwick, Coventry, United Kingdom
| | | | - Rama K Mallampalli
- 9Department of Medicine, Acute Lung Injury Center of Excellence, University of Pittsburgh, and VA Pittsburgh Healthcare System, Pittsburgh, Pennsylvania
| | - Marcus Conrad
- 6Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Neuherberg, Germany
| | - Hülya Bayir
- 10Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
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Group VIB calcium-independent phospholipase A2 (iPLA2γ) regulates platelet activation, hemostasis and thrombosis in mice. PLoS One 2014; 9:e109409. [PMID: 25313821 PMCID: PMC4196902 DOI: 10.1371/journal.pone.0109409] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 08/31/2014] [Indexed: 11/19/2022] Open
Abstract
In platelets, group IVA cytosolic phospholipase A2 (cPLA2α) has been implicated as a key regulator in the hydrolysis of platelet membrane phospholipids, leading to pro-thrombotic thromboxane A2 and anti-thrombotic 12-(S)-hydroxyeicosatetranoic acid production. However, studies using cPLA2α-deficient mice have indicated that other PLA2(s) may also be involved in the hydrolysis of platelet glycerophospholipids. In this study, we found that group VIB Ca2+-independent PLA2 (iPLA2γ)-deficient platelets showed decreases in adenosine diphosphate (ADP)-dependent aggregation and ADP- or collagen-dependent thromboxane A2 production. Electrospray ionization mass spectrometry analysis of platelet phospholipids revealed that fatty acyl compositions of ethanolamine plasmalogen and phosphatidylglycerol were altered in platelets from iPLA2γ-null mice. Furthermore, mice lacking iPLA2γ displayed prolonged bleeding times and were protected against pulmonary thromboembolism. These results suggest that iPLA2γ is an additional, long-sought-after PLA2 that hydrolyzes platelet membranes and facilitates platelet aggregation in response to ADP.
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46
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Nordmann C, Strokin M, Schönfeld P, Reiser G. Putative roles of Ca(2+) -independent phospholipase A2 in respiratory chain-associated ROS production in brain mitochondria: influence of docosahexaenoic acid and bromoenol lactone. J Neurochem 2014; 131:163-76. [PMID: 24923354 DOI: 10.1111/jnc.12789] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 06/05/2014] [Accepted: 06/10/2014] [Indexed: 11/28/2022]
Abstract
Ca(2+) -independent phospholipase A2 (iPLA2 ) is hypothesized to control mitochondrial reactive oxygen species (ROS) generation. Here, we modulated the influence of iPLA2 -induced liberation of non-esterified free fatty acids on ROS generation associated with the electron transport chain. We demonstrate enzymatic activity of membrane-associated iPLA2 in native, energized rat brain mitochondria (RBM). Theoretically, enhanced liberation of free fatty acids by iPLA2 modulates mitochondrial ROS generation, either attenuating the reversed electron transport (RET) or deregulating the forward electron transport of electron transport chain. For mimicking such conditions, we probed the effect of docosahexaenoic acid (DHA), a major iPLA2 product on ROS generation. We demonstrate that the adenine nucleotide translocase partly mediates DHA-induced uncoupling, and that low micromolar DHA concentrations diminish RET-dependent ROS generation. Uncoupling proteins have no effect, but the adenine nucleotide translocase inhibitor carboxyatractyloside attenuates DHA-linked uncoupling effect on RET-dependent ROS generation. Under physiological conditions of forward electron transport, low micromolar DHA stimulates ROS generation. Finally, exposure of RBM to the iPLA2 inhibitor bromoenol lactone (BEL) enhanced ROS generation. BEL diminished RBM glutathione content. BEL-treated RBM exhibits reduced Ca(2+) retention capacity and partial depolarization. Thus, we rebut the view that iPLA2 attenuates oxidative stress in brain mitochondria. However, the iPLA2 inhibitor BEL has detrimental activities on energy-dependent mitochondrial functions. The Ca(2+) -independent phospholipase A2 (iPLA2 ), a FFA (free fatty acids)-generating membrane-attached mitochondrial phospholipase, is potential to regulate ROS (reactive oxygen species) generation by mitochondria. FFA can either decrease reversed electron transport (RET)-linked or enhance forward electron transport (FET)-linked ROS generation. In the physiological mode of FET, iPLA2 activity increases ROS generation. The iPLA2 inhibitor BEL exerts detrimental effects on energy-dependent mitochondrial functions.
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Affiliation(s)
- Caroline Nordmann
- Institut für Neurobiochemie, Medizinische Fakultät, Otto-von-Guericke-Universität Magdeburg, Magdeburg, Germany
| | - Mikhail Strokin
- Institut für Neurobiochemie, Medizinische Fakultät, Otto-von-Guericke-Universität Magdeburg, Magdeburg, Germany
| | - Peter Schönfeld
- Institut für Biochemie und Zellbiologie, Medizinische Fakultät, Otto-von-Guericke-Universität Magdeburg, Magdeburg, Germany
| | - Georg Reiser
- Institut für Neurobiochemie, Medizinische Fakultät, Otto-von-Guericke-Universität Magdeburg, Magdeburg, Germany
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47
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Figueiredo CR, Matsuo AL, Pereira FV, Rabaça AN, Farias CF, Girola N, Massaoka MH, Azevedo RA, Scutti JAB, Arruda DC, Silva LP, Rodrigues EG, Lago JHG, Travassos LR, Silva RMG. Pyrostegia venusta heptane extract containing saturated aliphatic hydrocarbons induces apoptosis on B16F10-Nex2 melanoma cells and displays antitumor activity in vivo. Pharmacogn Mag 2014; 10:S363-76. [PMID: 24991116 PMCID: PMC4078348 DOI: 10.4103/0973-1296.133284] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Revised: 09/25/2013] [Accepted: 05/28/2014] [Indexed: 12/30/2022] Open
Abstract
Background: Pyrostegia venusta (Ker. Gawl.) Miers (Bignoniacea) is a medicinal plant from the Brazilian Cerrado used to treat leucoderma and common diseases of the respiratory system. Objective: To investigate the antitumor activity of P.venusta extracts against melanoma. Materials and Methods: The cytotoxic activity and tumor induced cell death of heptane extract (HE) from P. venusta flowers was evaluated against murine melanoma B16F10-Nex2 cells in vitro and in a syngeneic model in vivo. Results: We found that HE induced apoptosis in melanoma cells by disruption of the mitochondrial membrane potential, induction of reactive oxygen species and late apoptosis evidenced by plasma membrane blebbing, cell shrinkage, chromatin condensation and DNA fragmentation, exposure of phosphatidylserine on the cell surface and activation of caspase-2,-3,-8,-9. HE was also protective against singeneyc subcutaneous melanoma HE compounds were also able to induce cell cycle arrest at G2/M phases on tumor cells. On fractionation of HE in silica gel we isolated a cytotoxic fraction that contained a mixture of saturated hydrocarbons identified by 1H NMR and GC-MS analyses. Predominant species were octacosane (C28H58-36%) and triacontane (C30H62-13%), which individually showed significant cytotoxic activity against murine melanoma B16F10-Nex2 cells in vitro and a very promising antitumor protection against subcutaneous melanoma in vivo. Conclusion: The results suggest that the components of the heptane extract, mainly octasane and triacontane, which showed antitumor properties in experimental melanoma upon regional administration, might also be therapeutic in human cancer, such as in the mostly epidermal and slowly invasive melanomas, such as acral lentiginous melanoma, as an adjuvant treatment to surgical excision.
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Affiliation(s)
- Carlos R Figueiredo
- Departments of Microbiology, Immunology and Parasitology, Cell Biology Division and Experimental Oncology Unit (UNONEX), Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Alisson L Matsuo
- Departments of Microbiology, Immunology and Parasitology, Cell Biology Division and Experimental Oncology Unit (UNONEX), Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Felipe V Pereira
- Departments of Microbiology, Immunology and Parasitology, Cell Biology Division and Experimental Oncology Unit (UNONEX), Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Aline N Rabaça
- Departments of Microbiology, Immunology and Parasitology, Cell Biology Division and Experimental Oncology Unit (UNONEX), Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Camyla F Farias
- Departments of Microbiology, Immunology and Parasitology, Cell Biology Division and Experimental Oncology Unit (UNONEX), Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Nátalia Girola
- Departments of Microbiology, Immunology and Parasitology, Cell Biology Division and Experimental Oncology Unit (UNONEX), Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Mariana H Massaoka
- Departments of Microbiology, Immunology and Parasitology, Cell Biology Division and Experimental Oncology Unit (UNONEX), Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Ricardo A Azevedo
- Departments of Microbiology, Immunology and Parasitology, Cell Biology Division and Experimental Oncology Unit (UNONEX), Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Jorge A B Scutti
- Departments of Microbiology, Immunology and Parasitology, Cell Biology Division and Experimental Oncology Unit (UNONEX), Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Denise C Arruda
- Departments of Microbiology, Immunology and Parasitology, Cell Biology Division and Experimental Oncology Unit (UNONEX), Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Luciana P Silva
- Department of Biological Sciences, Phytochemistry Laboratory. Universidade Estadual Paulista (UNESP), Assis, São Paulo State, Brazil
| | - Elaine G Rodrigues
- Departments of Microbiology, Immunology and Parasitology, Cell Biology Division and Experimental Oncology Unit (UNONEX), Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - João Henrique G Lago
- Institute of Environmental, Chemical and Pharmaceutical Sciences, Federal University of São Paulo (UNIFESP), Diadema, São Paulo, Brazil
| | - Luiz R Travassos
- Departments of Microbiology, Immunology and Parasitology, Cell Biology Division and Experimental Oncology Unit (UNONEX), Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Regildo M G Silva
- Department of Biological Sciences, Phytochemistry Laboratory. Universidade Estadual Paulista (UNESP), Assis, São Paulo State, Brazil
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Tyurina YY, Poloyac SM, Tyurin VA, Kapralov AA, Jiang J, Anthonymuthu TS, Kapralova VI, Vikulina AS, Jung MY, Epperly MW, Mohammadyani D, Klein-Seetharaman J, Jackson TC, Kochanek PM, Pitt BR, Greenberger JS, Vladimirov YA, Bayır H, Kagan VE. A mitochondrial pathway for biosynthesis of lipid mediators. Nat Chem 2014; 6:542-52. [PMID: 24848241 PMCID: PMC4201180 DOI: 10.1038/nchem.1924] [Citation(s) in RCA: 120] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 03/16/2014] [Indexed: 01/20/2023]
Abstract
The central role of mitochondria in metabolic pathways and in cell-death mechanisms requires sophisticated signalling systems. Essential in this signalling process is an array of lipid mediators derived from polyunsaturated fatty acids. However, the molecular machinery for the production of oxygenated polyunsaturated fatty acids is localized in the cytosol and their biosynthesis has not been identified in mitochondria. Here we report that a range of diversified polyunsaturated molecular species derived from a mitochondria-specific phospholipid, cardiolipin (CL), is oxidized by the intermembrane-space haemoprotein, cytochrome c. We show that a number of oxygenated CL species undergo phospholipase A2-catalysed hydrolysis and thus generate multiple oxygenated fatty acids, including well-known lipid mediators. This represents a new biosynthetic pathway for lipid mediators. We demonstrate that this pathway, which includes the oxidation of polyunsaturated CLs and accumulation of their hydrolysis products (oxygenated linoleic, arachidonic acids and monolysocardiolipins), is activated in vivo after acute tissue injury.
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Affiliation(s)
- Yulia Y. Tyurina
- Center for Free Radical and Antioxidant Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
| | - Samuel M. Poloyac
- Department of Pharmaceutical Sciences, School of Pharmacy, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
| | - Vladimir A. Tyurin
- Center for Free Radical and Antioxidant Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
- Department of Environmental Health, Graduate School of Public Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
| | - Alexander A. Kapralov
- Center for Free Radical and Antioxidant Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
- Department of Environmental Health, Graduate School of Public Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
| | - Jianfei Jiang
- Center for Free Radical and Antioxidant Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
- Department of Environmental Health, Graduate School of Public Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
| | - Tamil Selvan Anthonymuthu
- Center for Free Radical and Antioxidant Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
- Department of Critical Care Medicine, Safar Center for Resuscitation Research, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
| | - Valentina I. Kapralova
- Center for Free Radical and Antioxidant Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
- Department of Environmental Health, Graduate School of Public Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
| | - Anna S. Vikulina
- Center for Free Radical and Antioxidant Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
- Department of Environmental Health, Graduate School of Public Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
- Department of Biophysics, MV Lomonosov Moscow State University, Moscow, Russia
| | - Mi-Yeon Jung
- Center for Free Radical and Antioxidant Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
- Department of Environmental Health, Graduate School of Public Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
| | - Michael W. Epperly
- Department of Radiation Oncology, School of Medicine, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
| | - Dariush Mohammadyani
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
| | | | - Travis C. Jackson
- Department of Critical Care Medicine, Safar Center for Resuscitation Research, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
| | - Patrick M. Kochanek
- Department of Critical Care Medicine, Safar Center for Resuscitation Research, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
| | - Bruce R. Pitt
- Department of Environmental Health, Graduate School of Public Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
- Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
| | - Joel S. Greenberger
- Department of Radiation Oncology, School of Medicine, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
| | - Yury A. Vladimirov
- Department of Biophysics, MV Lomonosov Moscow State University, Moscow, Russia
| | - Hülya Bayır
- Center for Free Radical and Antioxidant Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
- Department of Critical Care Medicine, Safar Center for Resuscitation Research, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
| | - Valerian E. Kagan
- Center for Free Radical and Antioxidant Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
- Department of Environmental Health, Graduate School of Public Health, Swanson School of Engineering, University of Pittsburgh, Pittsburgh PA 15213, USA
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49
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Rauckhorst AJ, Broekemeier KM, Pfeiffer DR. Regulation of the Ca(2+)-independent phospholipase A2 in liver mitochondria by changes in the energetic state. J Lipid Res 2014; 55:826-36. [PMID: 24586040 DOI: 10.1194/jlr.m043307] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The effect of electron transport chain redox status on activity of the mitochondrial Ca(2+)-independent phospholipase A2 (iPLA2) has been examined. When oxidizing NAD-linked substrates, the enzyme is not active unless deenergization occurs. Uncoupler, rotenone, antimycin A, and cyanide are equally effective at upregulating the enzyme, while oligomycin is ineffective. Thenoyltrifluoroacetone causes deenergization and activates the enzyme, but only if succinate is the respiratory substrate. These findings show that the mitochondrial iPLA2 responds to the energetic state overall, rather than to the redox status of individual electron transport chain complexes. With NAD-linked substrates, and using rotenone to deenergize, iPLA2 activation can be reversed by adding succinate to reestablish a membrane potential. For this purpose, ascorbate plus N,N,N'N'-tetramethyl-phenylenediamine can be used instead of succinate and is equally effective. With succinate as substrate, the membrane potential can be reduced in a graded and stable fashion by adding increasing concentrations of malonate, which is a competitive inhibitor of succinate utilization. A partial and stable activation of the iPLA2 accompanies partial deenergization. These findings suggest that in addition to the several functions that have been proposed, the mitochondrial iPLA2 may help to coordinate local capillary blood flow with changing energy demands.
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Affiliation(s)
- Adam J Rauckhorst
- Departments of Molecular and Cellular Biochemistry Ohio State University, Columbus, OH 43210
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50
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pPLA: Patatin-Related Phospholipase As with Multiple Biological Functions. SIGNALING AND COMMUNICATION IN PLANTS 2014. [DOI: 10.1007/978-3-642-42011-5_5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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