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Jabůrek M, Klöppel E, Průchová P, Mozheitova O, Tauber J, Engstová H, Ježek P. Mitochondria to plasma membrane redox signaling is essential for fatty acid β-oxidation-driven insulin secretion. Redox Biol 2024; 75:103283. [PMID: 39067330 PMCID: PMC11332078 DOI: 10.1016/j.redox.2024.103283] [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: 07/17/2024] [Revised: 07/22/2024] [Accepted: 07/22/2024] [Indexed: 07/30/2024] Open
Abstract
We asked whether acute redox signaling from mitochondria exists concomitantly to fatty acid- (FA-) stimulated insulin secretion (FASIS) at low glucose by pancreatic β-cells. We show that FA β-oxidation produces superoxide/H2O2, providing: i) mitochondria-to-plasma-membrane redox signaling, closing KATP-channels synergically with elevated ATP (substituting NADPH-oxidase-4-mediated H2O2-signaling upon glucose-stimulated insulin secretion); ii) activation of redox-sensitive phospholipase iPLA2γ/PNPLA8, cleaving mitochondrial FAs, enabling metabotropic GPR40 receptors to amplify insulin secretion (IS). At fasting glucose, palmitic acid stimulated IS in wt mice; palmitic, stearic, lauric, oleic, linoleic, and hexanoic acids also in perifused pancreatic islets (PIs), with suppressed 1st phases in iPLA2γ/PNPLA8-knockout mice/PIs. Extracellular/cytosolic H2O2-monitoring indicated knockout-independent redox signals, blocked by mitochondrial antioxidant SkQ1, etomoxir, CPT1 silencing, and catalase overexpression, all inhibiting FASIS, keeping ATP-sensitive K+-channels open, and diminishing cytosolic [Ca2+]-oscillations. FASIS in mice was a postprandially delayed physiological event. Redox signals of FA β-oxidation are thus documented, reaching the plasma membrane, essentially co-stimulating IS.
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Affiliation(s)
- Martin Jabůrek
- Department of Mitochondrial Physiology, No.75, Institute of Physiology of the Czech Academy of Sciences, Vídeňská 1083, Prague, 14220, Czech Republic
| | - Eduardo Klöppel
- Department of Mitochondrial Physiology, No.75, Institute of Physiology of the Czech Academy of Sciences, Vídeňská 1083, Prague, 14220, Czech Republic
| | - Pavla Průchová
- Department of Mitochondrial Physiology, No.75, Institute of Physiology of the Czech Academy of Sciences, Vídeňská 1083, Prague, 14220, Czech Republic
| | - Oleksandra Mozheitova
- Department of Mitochondrial Physiology, No.75, Institute of Physiology of the Czech Academy of Sciences, Vídeňská 1083, Prague, 14220, Czech Republic
| | - Jan Tauber
- Department of Mitochondrial Physiology, No.75, Institute of Physiology of the Czech Academy of Sciences, Vídeňská 1083, Prague, 14220, Czech Republic
| | - Hana Engstová
- Department of Mitochondrial Physiology, No.75, Institute of Physiology of the Czech Academy of Sciences, Vídeňská 1083, Prague, 14220, Czech Republic
| | - Petr Ježek
- Department of Mitochondrial Physiology, No.75, Institute of Physiology of the Czech Academy of Sciences, Vídeňská 1083, Prague, 14220, Czech Republic.
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Messina M, Vaz FM, Rahman S. Mitochondrial membrane synthesis, remodelling and cellular trafficking. J Inherit Metab Dis 2024. [PMID: 38872485 DOI: 10.1002/jimd.12766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Revised: 05/14/2024] [Accepted: 05/21/2024] [Indexed: 06/15/2024]
Abstract
Mitochondria are dynamic cellular organelles with complex roles in metabolism and signalling. Primary mitochondrial disorders are a group of approximately 400 monogenic disorders arising from pathogenic genetic variants impacting mitochondrial structure, ultrastructure and/or function. Amongst these disorders, defects of complex lipid biosynthesis, especially of the unique mitochondrial membrane lipid cardiolipin, and membrane biology are an emerging group characterised by clinical heterogeneity, but with recurrent features including cardiomyopathy, encephalopathy, neurodegeneration, neuropathy and 3-methylglutaconic aciduria. This review discusses lipid synthesis in the mitochondrial membrane, the mitochondrial contact site and cristae organising system (MICOS), mitochondrial dynamics and trafficking, and the disorders associated with defects of each of these processes. We highlight overlapping functions of proteins involved in lipid biosynthesis and protein import into the mitochondria, pointing to an overarching coordination and synchronisation of mitochondrial functions. This review also focuses on membrane interactions between mitochondria and other organelles, namely the endoplasmic reticulum, peroxisomes, lysosomes and lipid droplets. We signpost disorders of these membrane interactions that may explain the observation of secondary mitochondrial dysfunction in heterogeneous pathological processes. Disruption of these organellar interactions ultimately impairs cellular homeostasis and organismal health, highlighting the central role of mitochondria in human health and disease.
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Affiliation(s)
- Martina Messina
- Mitochondrial Research Group, Genetics and Genomic Medicine Department, UCL Great Ormond Street Institute of Child Health, London, UK
- Metabolic Unit, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Frédéric M Vaz
- Department of Laboratory Medicine and Pediatrics, Laboratory Genetic Metabolic Diseases, Emma Children's Hospital, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands
- Amsterdam Gastroenterology Endocrinology Metabolism, Inborn Errors of Metabolism, Amsterdam, The Netherlands
| | - Shamima Rahman
- Mitochondrial Research Group, Genetics and Genomic Medicine Department, UCL Great Ormond Street Institute of Child Health, London, UK
- Metabolic Unit, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
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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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Žuna K, Tyschuk T, Beikbaghban T, Sternberg F, Kreiter J, Pohl EE. The 2-oxoglutarate/malate carrier extends the family of mitochondrial carriers capable of fatty acid and 2,4-dinitrophenol-activated proton transport. Acta Physiol (Oxf) 2024; 240:e14143. [PMID: 38577966 DOI: 10.1111/apha.14143] [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: 10/19/2023] [Revised: 03/06/2024] [Accepted: 03/11/2024] [Indexed: 04/06/2024]
Abstract
AIMS Metabolic reprogramming in cancer cells has been linked to mitochondrial dysfunction. The mitochondrial 2-oxoglutarate/malate carrier (OGC) has been suggested as a potential target for preventing cancer progression. Although OGC is involved in the malate/aspartate shuttle, its exact role in cancer metabolism remains unclear. We aimed to investigate whether OGC may contribute to the alteration of mitochondrial inner membrane potential by transporting protons. METHODS The expression of OGC in mouse tissues and cancer cells was investigated by PCR and Western blot analysis. The proton transport function of recombinant murine OGC was evaluated by measuring the membrane conductance (Gm) of planar lipid bilayers. OGC-mediated substrate transport was measured in proteoliposomes using 14C-malate. RESULTS OGC increases proton Gm only in the presence of natural (long-chain fatty acids, FA) or chemical (2,4-dinitrophenol) protonophores. The increase in OGC activity directly correlates with the increase in the number of unsaturated bonds of the FA. OGC substrates and inhibitors compete with FA for the same protein binding site. Arginine 90 was identified as a critical amino acid for the binding of FA, ATP, 2-oxoglutarate, and malate, which is a first step towards understanding the OGC-mediated proton transport mechanism. CONCLUSION OGC extends the family of mitochondrial transporters with dual function: (i) metabolite transport and (ii) proton transport facilitated in the presence of protonophores. Elucidating the contribution of OGC to uncoupling may be essential for the design of targeted drugs for the treatment of cancer and other metabolic diseases.
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Affiliation(s)
- Kristina Žuna
- Physiology and Biophysics, Department of Biological Sciences and Pathobiology, University of Veterinary Medicine, Vienna, Austria
| | - Tatyana Tyschuk
- Physiology and Biophysics, Department of Biological Sciences and Pathobiology, University of Veterinary Medicine, Vienna, Austria
| | - Taraneh Beikbaghban
- Physiology and Biophysics, Department of Biological Sciences and Pathobiology, University of Veterinary Medicine, Vienna, Austria
| | - Felix Sternberg
- Physiology and Biophysics, Department of Biological Sciences and Pathobiology, University of Veterinary Medicine, Vienna, Austria
| | - Jürgen Kreiter
- Physiology and Biophysics, Department of Biological Sciences and Pathobiology, University of Veterinary Medicine, Vienna, Austria
| | - Elena E Pohl
- Physiology and Biophysics, Department of Biological Sciences and Pathobiology, University of Veterinary Medicine, Vienna, Austria
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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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Wang LM, Zhang WL, Lyu N, Suo YR, Yang L, Yu B, Jiang XJ. Research Advance of Chinese Medicine in Treating Atherosclerosis: Focus on Lipoprotein-Associated Phospholipase A2. Chin J Integr Med 2024; 30:277-288. [PMID: 38057549 DOI: 10.1007/s11655-023-3611-6] [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] [Accepted: 04/24/2023] [Indexed: 12/08/2023]
Abstract
As a serious cardiovascular disease, atherosclerosis (AS) causes chronic inflammation and oxidative stress in the body and poses a threat to human health. Lipoprotein-associated phospholipase A2 (Lp-PLA2) is a member of the phospholipase A2 (PLA2) family, and its elevated levels have been shown to contribute to AS. Lp-PLA2 is closely related to a variety of lipoproteins, and its role in promoting inflammatory responses and oxidative stress in AS is mainly achieved by hydrolyzing oxidized phosphatidylcholine (oxPC) to produce lysophosphatidylcholine (lysoPC). Moreover, macrophage apoptosis within plaque is promoted by localized Lp-PLA2 which also promotes plaque instability. This paper reviews those researches of Chinese medicine in treating AS via reducing Lp-PLA2 levels to guide future experimental studies and clinical applications related to AS.
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Affiliation(s)
- Lu-Ming Wang
- School of Integrative Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China
| | - Wen-Lan Zhang
- School of Integrative Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China
| | - Nuan Lyu
- School of Integrative Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China
| | - Yan-Rong Suo
- Department of Traditional Chinese Medicine, Ganzhou People's Hospital, Ganzhou, Jiangxi Province, 341000, China
| | - Lin Yang
- School of Integrative Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China
| | - Bin Yu
- School of Medical Technology, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China.
| | - Xi-Juan Jiang
- School of Integrative Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 301617, China
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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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Membrane Lipid Reshaping Underlies Oxidative Stress Sensing by the Mitochondrial Proteins UCP1 and ANT1. Antioxidants (Basel) 2022; 11:antiox11122314. [PMID: 36552523 PMCID: PMC9774536 DOI: 10.3390/antiox11122314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/17/2022] [Accepted: 11/18/2022] [Indexed: 11/24/2022] Open
Abstract
Oxidative stress and ROS are important players in the pathogenesis of numerous diseases. In addition to directly altering proteins, ROS also affects lipids with negative intrinsic curvature such as phosphatidylethanolamine (PE), producing PE adducts and lysolipids. The formation of PE adducts potentiates the protonophoric activity of mitochondrial uncoupling proteins, but the molecular mechanism remains unclear. Here, we linked the ROS-mediated change in lipid shape to the mechanical properties of the membrane and the function of uncoupling protein 1 (UCP1) and adenine nucleotide translocase 1 (ANT1). We show that the increase in the protonophoric activity of both proteins occurs due to the decrease in bending modulus in lipid bilayers in the presence of lysophosphatidylcholines (OPC and MPC) and PE adducts. Moreover, MD simulations showed that modified PEs and lysolipids change the lateral pressure profile of the membrane in the same direction and by the similar amplitude, indicating that modified PEs act as lipids with positive intrinsic curvature. Both results indicate that oxidative stress decreases stored curvature elastic stress (SCES) in the lipid bilayer membrane. We demonstrated that UCP1 and ANT1 sense SCES and proposed a novel regulatory mechanism for the function of these proteins. The new findings should draw the attention of the scientific community to this important and unexplored area of redox biochemistry.
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Ježek P, Holendová B, Jabůrek M, Dlasková A, Plecitá-Hlavatá L. Contribution of Mitochondria to Insulin Secretion by Various Secretagogues. Antioxid Redox Signal 2022; 36:920-952. [PMID: 34180254 PMCID: PMC9125579 DOI: 10.1089/ars.2021.0113] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Significance: Mitochondria determine glucose-stimulated insulin secretion (GSIS) in pancreatic β-cells by elevating ATP synthesis. As the metabolic and redox hub, mitochondria provide numerous links to the plasma membrane channels, insulin granule vesicles (IGVs), cell redox, NADH, NADPH, and Ca2+ homeostasis, all affecting insulin secretion. Recent Advances: Mitochondrial redox signaling was implicated in several modes of insulin secretion (branched-chain ketoacid [BCKA]-, fatty acid [FA]-stimulated). Mitochondrial Ca2+ influx was found to enhance GSIS, reflecting cytosolic Ca2+ oscillations induced by action potential spikes (intermittent opening of voltage-dependent Ca2+ and K+ channels) or the superimposed Ca2+ release from the endoplasmic reticulum (ER). The ATPase inhibitory factor 1 (IF1) was reported to tune the glucose sensitivity range for GSIS. Mitochondrial protein kinase A was implicated in preventing the IF1-mediated inhibition of the ATP synthase. Critical Issues: It is unknown how the redox signal spreads up to the plasma membrane and what its targets are, what the differences in metabolic, redox, NADH/NADPH, and Ca2+ signaling, and homeostasis are between the first and second GSIS phase, and whether mitochondria can replace ER in the amplification of IGV exocytosis. Future Directions: Metabolomics studies performed to distinguish between the mitochondrial matrix and cytosolic metabolites will elucidate further details. Identifying the targets of cell signaling into mitochondria and of mitochondrial retrograde metabolic and redox signals to the cell will uncover further molecular mechanisms for insulin secretion stimulated by glucose, BCKAs, and FAs, and the amplification of secretion by glucagon-like peptide (GLP-1) and metabotropic receptors. They will identify the distinction between the hub β-cells and their followers in intact and diabetic states. Antioxid. Redox Signal. 36, 920-952.
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Affiliation(s)
- Petr Ježek
- Department of Mitochondrial Physiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Blanka Holendová
- Department of Mitochondrial Physiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Martin Jabůrek
- Department of Mitochondrial Physiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Andrea Dlasková
- Department of Mitochondrial Physiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Lydie Plecitá-Hlavatá
- Department of Mitochondrial Physiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
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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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Antioxidant Role and Cardiolipin Remodeling by Redox-Activated Mitochondrial Ca 2+-Independent Phospholipase A 2γ in the Brain. Antioxidants (Basel) 2022; 11:antiox11020198. [PMID: 35204081 PMCID: PMC8868467 DOI: 10.3390/antiox11020198] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 01/14/2022] [Accepted: 01/18/2022] [Indexed: 02/01/2023] Open
Abstract
Mitochondrial Ca2+-independent phospholipase A2γ (iPLA2γ/PNPLA8) was previously shown to be directly activated by H2O2 and release free fatty acids (FAs) for FA-dependent H+ transport mediated by the adenine nucleotide translocase (ANT) or uncoupling protein 2 (UCP2). The resulting mild mitochondrial uncoupling and consequent partial attenuation of mitochondrial superoxide production lead to an antioxidant effect. However, the antioxidant role of iPLA2γ in the brain is not completely understood. Here, using wild-type and iPLA2γ-KO mice, we demonstrate the ability of tert-butylhydroperoxide (TBHP) to activate iPLA2γ in isolated brain mitochondria, with consequent liberation of FAs and lysophospholipids. The liberated FA caused an increase in respiratory rate, which was fully inhibited by carboxyatractyloside (CATR), a specific inhibitor of ANT. Employing detailed lipidomic analysis, we also demonstrate a typical cleavage pattern for TBHP-activated iPLA2γ, reflecting cleavage of glycerophospholipids from both sn-1 and sn-2 positions releasing saturated FAs, monoenoic FAs, and predominant polyunsaturated FAs. The acute antioxidant role of iPLA2γ-released FAs is supported by monitoring both intramitochondrial superoxide and extramitochondrial H2O2 release. We also show that iPLA2γ-KO mice were more sensitive to stimulation by pro-inflammatory lipopolysaccharide, as reflected by the concomitant increase in protein carbonyls in the brain and pro-inflammatory IL-6 release in the serum. These data support the antioxidant and anti-inflammatory role of iPLA2γ in vivo. Our data also reveal a substantial decrease of several high molecular weight cardiolipin (CL) species and accumulation of low molecular weight CL species in brain mitochondria of iPLA2γ-KO mice. Collectively, our results support a key role of iPLA2γ in the remodeling of lower molecular weight immature cardiolipins with predominantly saturated acyl chains to high molecular weight mature cardiolipins with highly unsaturated PUFA acyl chains, typical for the brain.
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Sikiric P, Skrtic A, Gojkovic S, Krezic I, Zizek H, Lovric E, Sikiric S, Knezevic M, Strbe S, Milavic M, Kokot A, Blagaic AB, Seiwerth S. Cytoprotective gastric pentadecapeptide BPC 157 resolves major vessel occlusion disturbances, ischemia-reperfusion injury following Pringle maneuver, and Budd-Chiari syndrome. World J Gastroenterol 2022; 28:23-46. [PMID: 35125818 PMCID: PMC8793015 DOI: 10.3748/wjg.v28.i1.23] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 05/14/2021] [Accepted: 12/22/2021] [Indexed: 02/06/2023] Open
Abstract
The stable gastric pentadecapeptide BPC 157 counteracts various venous occlusion-induced syndromes. Summarized are all these arguments, in the Robert’s cytoprotection concept, to substantiate the resolution of different major vessel occlusion disturbances, in particular ischemia-reperfusion injury following the Pringle maneuver and Budd-Chiari syndrome, which was obtained by BPC 157 therapy. Conceptually, there is a new point, namely, endothelium maintenance to epithelium maintenance (the recruitment of collateral blood vessels to compensate for vessel occlusion and reestablish blood flow or bypass the occluded or ruptured vessel). In this paper, we summarize the evidence of the native cytoprotective gastric pentadecapeptide BPC 157, which is stable in the human gastric juice, is a membrane stabilizer and counteracts gut-leaky syndrome. As a particular target, it is distinctive from the standard peptide growth factors, involving particular molecular pathways and controlling VEGF and NO pathways. In the early 1990s, BPC 157 appeared as a late outbreak of the Robert’s and Szabo’s cytoprotection-organoprotection concept, like the previous theoretical/practical breakthrough in the 1980s and the brain-gut axis and gut-brain axis. As the time went on, with its reported effects, it is likely most useful theory practical implementation and justification. Meantime, several reviews suggest that BPC 157, which does not have a lethal dose, has profound cytoprotective activity, used to be demonstrated in ulcerative colitis and multiple sclerosis trials. Likely, it may bring the theory to practical application, starting with the initial argument, no degradation in human gastric juice for more than 24 h, and thereby, the therapeutic effectiveness (including via a therapeutic per-oral regimen) and pleiotropic beneficial effects.
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Affiliation(s)
- Predrag Sikiric
- Department of Pharmacology, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
| | - Anita Skrtic
- Department of Pathology, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
| | - Slaven Gojkovic
- Department of Pharmacology, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
| | - Ivan Krezic
- Department of Pharmacology, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
| | - Helena Zizek
- Department of Pharmacology, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
| | - Eva Lovric
- Department of Pathology, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
| | - Suncana Sikiric
- Department of Pathology, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
| | - Mario Knezevic
- Department of Pharmacology, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
| | - Sanja Strbe
- Department of Pharmacology, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
| | - Marija Milavic
- Department of Pathology, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
| | - Antonio Kokot
- Department of Anatomy and Neuroscience, Faculty of Medicine Osijek, J.J.Strossmayer University of Osijek, Osijek 31000, Croatia
| | - Alenka Boban Blagaic
- Department of Pharmacology, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
| | - Sven Seiwerth
- Department of Pathology, School of Medicine, University of Zagreb, Zagreb 10000, Croatia
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13
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Ježek P. Mitochondrial Redox Regulations and Redox Biology of Mitochondria. Antioxidants (Basel) 2021; 10:antiox10121921. [PMID: 34943024 PMCID: PMC8750772 DOI: 10.3390/antiox10121921] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 11/28/2021] [Accepted: 11/28/2021] [Indexed: 02/06/2023] Open
Affiliation(s)
- Petr Ježek
- Department of Mitochondrial Physiology, No.75, Institute of Physiology of the Czech Academy of Sciences, 14220 Prague, Czech Republic
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14
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Dynamic Role of Phospholipases A2 in Health and Diseases in the Central Nervous System. Cells 2021; 10:cells10112963. [PMID: 34831185 PMCID: PMC8616333 DOI: 10.3390/cells10112963] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/19/2021] [Accepted: 10/27/2021] [Indexed: 12/20/2022] Open
Abstract
Phospholipids are major components in the lipid bilayer of cell membranes. These molecules are comprised of two acyl or alkyl groups and different phospho-base groups linked to the glycerol backbone. Over the years, substantial interest has focused on metabolism of phospholipids by phospholipases and the role of their metabolic products in mediating cell functions. The high levels of polyunsaturated fatty acids (PUFA) in the central nervous system (CNS) have led to studies centered on phospholipases A2 (PLA2s), enzymes responsible for cleaving the acyl groups at the sn-2 position of the phospholipids and resulting in production of PUFA and lysophospholipids. Among the many subtypes of PLA2s, studies have centered on three major types of PLA2s, namely, the calcium-dependent cytosolic cPLA2, the calcium-independent iPLA2 and the secretory sPLA2. These PLA2s are different in their molecular structures, cellular localization and, thus, production of lipid mediators with diverse functions. In the past, studies on specific role of PLA2 on cells in the CNS are limited, partly because of the complex cellular make-up of the nervous tissue. However, understanding of the molecular actions of these PLA2s have improved with recent advances in techniques for separation and isolation of specific cell types in the brain tissue as well as development of sensitive molecular tools for analyses of proteins and lipids. A major goal here is to summarize recent studies on the characteristics and dynamic roles of the three major types of PLA2s and their oxidative products towards brain health and neurological disorders.
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