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Watanabe N, Saito-Nakano Y, Kurisawa N, Otomo K, Suenaga K, Nakano K, Nozaki T. Fumagillin inhibits growth of the enteric protozoan parasite Entamoeba histolytica by covalently binding to and selectively inhibiting methionine aminopeptidase 2. Antimicrob Agents Chemother 2023; 67:e0056023. [PMID: 37874291 PMCID: PMC10648944 DOI: 10.1128/aac.00560-23] [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: 05/02/2023] [Accepted: 08/27/2023] [Indexed: 10/25/2023] Open
Abstract
Amebiasis is an important cause of morbidity and mortality worldwide, and caused by infection with the protozoan parasite Entamoeba histolytica. Metronidazole is currently the first-line drug despite adverse effects and concerns on the emergence of drug resistance. Fumagillin, a fungal metabolite from Aspergillus fumigatus, and its structurally related natural and synthetic compounds have been previously explored as potential anti-angiogenesis inhibitors for cancers, anti-microbial, and anti-obese compounds. Although fumagillin was used for human amebiasis in clinical trials in 1950s, the mode of action of fumagillin remains elusive until now. In this report, we showed that fumagillin covalently binds to methionine aminopeptidase 2 (MetAP2) and non-covalently but abundantly binds to patatin family phospholipase A (PLA). Susceptibility against fumagillin of the amebic strains in which expression of E. histolytica MetAP2 (EhMetAP2) gene was silenced increased compared to control strain. Conversely, overexpression of EhMetAP2 mutants that harbors amino acid substitutions responsible for resistance to ovalicin, a fumagillin analog, in human MetAP2, also resulted in decrease in fumagillin susceptibility. In contrast, neither gene silencing nor overexpression of E. histolytica PLA (EhPLA) affected fumagillin susceptibility. These data suggest that EhPLA is not essential and not the target of fumagillin for its amebicidal activity. Taken together, our data have demonstrated that EhMetAP2 is the primary target for amebicidal activity of fumagillin, and EhMetAP2 represents a rational explorable target for the development of alternative therapeutic agents against amebiasis.
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Affiliation(s)
- Natsuki Watanabe
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yumiko Saito-Nakano
- Department of Parasitology and Antimicrobial Resistance Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Naoaki Kurisawa
- Department of Chemistry, Faculty of Science and Technology, Keio University, Kanagawa, Japan
| | - Keisuke Otomo
- Department of Chemistry, Faculty of Science and Technology, Keio University, Kanagawa, Japan
| | - Kiyotake Suenaga
- Department of Chemistry, Faculty of Science and Technology, Keio University, Kanagawa, Japan
| | - Kentaro Nakano
- Degree Programs in Biology, Graduate School of Science and Technology, University of Tsukuba, Ibaraki, Japan
| | - Tomoyoshi Nozaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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2
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Alekseeva AS, Boldyrev IA. Alternative Targets for sPLA2 Activity: Role of Membrane-Enzyme Interactions. MEMBRANES 2023; 13:618. [PMID: 37504984 PMCID: PMC10384401 DOI: 10.3390/membranes13070618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 06/20/2023] [Accepted: 06/21/2023] [Indexed: 07/29/2023]
Abstract
The secreted phospholipases A2 (sPLA2s) play important roles both physiologically and pathologically, with their expression increasing significantly in diseases such as sepsis, inflammation, different cancers, glaucoma, obesity, Alzheimer's disease and even COVID-19. The fact has led to a large-scale search for inhibitors of these enzymes. In total, several dozen promising molecules have been proposed, but not a single one has successfully passed clinical trials. The failures in clinical studies motivated in-depth fundamental studies of PLA2s. Here we review alternative ways to control sPLA2 activity, outside its catalytic site. The concept can be realized by preventing sPLA2 from attaching to the membrane surface; by binding to an external protein which blocks sPLA2 hydrolytic activity; by preventing sPLA2 from orienting properly on the membrane surface; and by preventing substrate binding to the enzyme, keeping the catalytic site unaltered. Evidence in the literature is summarized in the review with the aim to serve as a starting point for new types of sPLA2 inhibitors.
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Affiliation(s)
- Anna S Alekseeva
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
| | - Ivan A Boldyrev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Moscow, Russia
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3
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Du H, Yang C, Nana AL, Seeley WW, Smolka M, Hu F. Progranulin inhibits phospholipase sPLA2-IIA to control neuroinflammation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.06.535844. [PMID: 37066328 PMCID: PMC10104136 DOI: 10.1101/2023.04.06.535844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
Mutations in the granulin (GRN) gene, resulting in haploinsufficiency of the progranulin (PGRN) protein, are a leading cause of frontotemporal lobar degeneration (FTLD) and PGRN polymorphisms are associated with Alzheimer's disease (AD) and Parkinson's disease (PD). PGRN is a key regulator of microglia-mediated inflammation but the mechanism is still unknown. Here we report that PGRN interacts with sPLA2-IIA, a secreted phospholipase involved in inflammatory responses, to downregulate sPLA2-IIA activities and levels. sPLA2-IIA expression modifies PGRN deficiency phenotypes in mice and sPLA2-IIA inhibition rescues inflammation and lysosomal abnormalities in PGRN deficient mice. Furthermore, FTLD patients with GRN mutations show increased levels of sPLA2-IIA in astrocytes. Our data support sPLA2-IIA as a critical target for PGRN and a novel therapeutic target for FTLD-GRN.
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Affiliation(s)
- Huan Du
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Cha Yang
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Alissa L. Nana
- Department of Neurology, University of California, San Francisco, CA 94158, USA
| | - William W. Seeley
- Department of Neurology, University of California, San Francisco, CA 94158, USA
- Department of Pathology, University of California, San Francisco, CA 94158, USA
| | - Marcus Smolka
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Fenghua Hu
- Department of Molecular Biology and Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
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4
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Castro-Amorim J, Novo de Oliveira A, Da Silva SL, Soares AM, Mukherjee AK, Ramos MJ, Fernandes PA. Catalytically Active Snake Venom PLA 2 Enzymes: An Overview of Its Elusive Mechanisms of Reaction. J Med Chem 2023; 66:5364-5376. [PMID: 37018514 PMCID: PMC10150362 DOI: 10.1021/acs.jmedchem.3c00097] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
Snake venom-secreted phospholipase A2 (svPLA2) enzymes, both catalytically active and inactive, are a central component in envenoming. These are responsible for disrupting the cell membrane's integrity, inducing a wide range of pharmacological effects, such as the necrosis of the bitten limb, cardiorespiratory arrest, edema, and anticoagulation. Although extensively characterized, the reaction mechanisms of enzymatic svPLA2 are still to be thoroughly understood. This review presents and analyses the most plausible reaction mechanisms for svPLA2, such as the "single-water mechanism" or the "assisted-water mechanism" initially proposed for the homologous human PLA2. All of the mechanistic possibilities are characterized by a highly conserved Asp/His/water triad and a Ca2+ cofactor. The extraordinary increase in activity induced by binding to a lipid-water interface, known as "interfacial activation," critical for the PLA2s activity, is also discussed. Finally, a potential catalytic mechanism for the postulated noncatalytic PLA2-like proteins is anticipated.
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Affiliation(s)
- Juliana Castro-Amorim
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal
| | - Ana Novo de Oliveira
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal
| | - Saulo Luís Da Silva
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal
| | - Andreimar M Soares
- Laboratory of Biotechnology of Proteins and Bioactive Compounds (LABIOPROT), Oswaldo Cruz Foundation, National Institute of Epidemiology in the Western Amazon (INCT-EpiAmO), Porto Velho, Rondônia 76812-245, Brazil
- Sao Lucas Universitary Center (UniSL), Porto Velho, Rondônia 76805-846, Brazil
| | - Ashis K Mukherjee
- Microbial Biotechnology and Protein Research Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur 784028, Assam, India
- Division of Life Sciences, Institute of Advanced Studies in Science and Technology, Vigyan Path, Garchuk, Paschim Boragaon, Guwahati 781035, Assam, India
| | - Maria João Ramos
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal
| | - Pedro A Fernandes
- LAQV, REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal
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5
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Secretory Phospholipases A2, from Snakebite Envenoming to a Myriad of Inflammation Associated Human Diseases-What Is the Secret of Their Activity? Int J Mol Sci 2023; 24:ijms24021579. [PMID: 36675102 PMCID: PMC9863470 DOI: 10.3390/ijms24021579] [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: 12/14/2022] [Revised: 01/05/2023] [Accepted: 01/11/2023] [Indexed: 01/15/2023] Open
Abstract
Secreted phospholipases of type A2 (sPLA2s) are proteins of 14-16 kDa present in mammals in different forms and at different body sites. They are involved in lipid transformation processes, and consequently in various immune, inflammatory, and metabolic processes. sPLA2s are also major components of snake venoms, endowed with various toxic and pharmacological properties. The activity of sPLA2s is not limited to the enzymatic one but, through interaction with different types of molecules, they exert other activities that are still little known and explored, both outside and inside the cells, as they can be endocytosed. The aim of this review is to analyze three features of sPLA2s, yet under-explored, knowledge of which could be crucial to understanding the activity of these proteins. The first feature is their disulphide bridge pattern, which has always been considered immutable and necessary for their stability, but which might instead be modulable. The second characteristic is their ability to undergo various post-translational modifications that would control their interaction with other molecules. The third feature is their ability to participate in active molecular condensates both on the surface and within the cell. Finally, the implications of these features in the design of anti-inflammatory drugs are discussed.
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6
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Khan SA, Ilies MA. The Phospholipase A2 Superfamily: Structure, Isozymes, Catalysis, Physiologic and Pathologic Roles. Int J Mol Sci 2023; 24:ijms24021353. [PMID: 36674864 PMCID: PMC9862071 DOI: 10.3390/ijms24021353] [Citation(s) in RCA: 23] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/23/2022] [Accepted: 01/06/2023] [Indexed: 01/13/2023] Open
Abstract
The phospholipase A2 (PLA2) superfamily of phospholipase enzymes hydrolyzes the ester bond at the sn-2 position of the phospholipids, generating a free fatty acid and a lysophospholipid. The PLA2s are amphiphilic in nature and work only at the water/lipid interface, acting on phospholipid assemblies rather than on isolated single phospholipids. The superfamily of PLA2 comprises at least six big families of isoenzymes, based on their structure, location, substrate specificity and physiologic roles. We are reviewing the secreted PLA2 (sPLA2), cytosolic PLA2 (cPLA2), Ca2+-independent PLA2 (iPLA2), lipoprotein-associated PLA2 (LpPLA2), lysosomal PLA2 (LPLA2) and adipose-tissue-specific PLA2 (AdPLA2), focusing on the differences in their structure, mechanism of action, substrate specificity, interfacial kinetics and tissue distribution. The PLA2s play important roles both physiologically and pathologically, with their expression increasing significantly in diseases such as sepsis, inflammation, different cancers, glaucoma, obesity and Alzheimer's disease, which are also detailed in this review.
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7
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Interplay between C1-inhibitor and group IIA secreted phospholipase A 2 impairs their respective function. Immunol Res 2023; 71:70-82. [PMID: 36385678 PMCID: PMC9845149 DOI: 10.1007/s12026-022-09331-7] [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: 07/22/2022] [Accepted: 10/14/2022] [Indexed: 11/18/2022]
Abstract
High levels of human group IIA secreted phospholipase A2 (hGIIA) have been associated with various inflammatory disease conditions. We have recently shown that hGIIA activity and concentration are increased in the plasma of patients with hereditary angioedema due to C1-inhibitor deficiency (C1-INH-HAE) and negatively correlate with C1-INH plasma activity. In this study, we analyzed whether the presence of both hGIIA and C1-INH impairs their respective function on immune cells. hGIIA, but not recombinant and plasma-derived C1-INH, stimulates the production of IL-6, CXCL8, and TNF-α from peripheral blood mononuclear cells (PBMCs). PBMC activation mediated by hGIIA is blocked by RO032107A, a specific hGIIA inhibitor. Interestingly, C1-INH inhibits the hGIIA-induced production of IL-6, TNF-α, and CXCL8, while it does not affect hGIIA enzymatic activity. On the other hand, hGIIA reduces the capacity of C1-INH at inhibiting C1-esterase activity. Spectroscopic and molecular docking studies suggest a possible interaction between hGIIA and C1-INH but further experiments are needed to confirm this hypothesis. Together, these results provide evidence for a new interplay between hGIIA and C1-INH, which may be important in the pathophysiology of hereditary angioedema.
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8
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Vyletelová V, Nováková M, Pašková Ľ. Alterations of HDL's to piHDL's Proteome in Patients with Chronic Inflammatory Diseases, and HDL-Targeted Therapies. Pharmaceuticals (Basel) 2022; 15:1278. [PMID: 36297390 PMCID: PMC9611871 DOI: 10.3390/ph15101278] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/03/2022] [Accepted: 10/14/2022] [Indexed: 09/10/2023] Open
Abstract
Chronic inflammatory diseases, such as rheumatoid arthritis, steatohepatitis, periodontitis, chronic kidney disease, and others are associated with an increased risk of atherosclerotic cardiovascular disease, which persists even after accounting for traditional cardiac risk factors. The common factor linking these diseases to accelerated atherosclerosis is chronic systemic low-grade inflammation triggering changes in lipoprotein structure and metabolism. HDL, an independent marker of cardiovascular risk, is a lipoprotein particle with numerous important anti-atherogenic properties. Besides the essential role in reverse cholesterol transport, HDL possesses antioxidative, anti-inflammatory, antiapoptotic, and antithrombotic properties. Inflammation and inflammation-associated pathologies can cause modifications in HDL's proteome and lipidome, transforming HDL from atheroprotective into a pro-atherosclerotic lipoprotein. Therefore, a simple increase in HDL concentration in patients with inflammatory diseases has not led to the desired anti-atherogenic outcome. In this review, the functions of individual protein components of HDL, rendering them either anti-inflammatory or pro-inflammatory are described in detail. Alterations of HDL proteome (such as replacing atheroprotective proteins by pro-inflammatory proteins, or posttranslational modifications) in patients with chronic inflammatory diseases and their impact on cardiovascular health are discussed. Finally, molecular, and clinical aspects of HDL-targeted therapies, including those used in therapeutical practice, drugs in clinical trials, and experimental drugs are comprehensively summarised.
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Affiliation(s)
| | | | - Ľudmila Pašková
- Department of Cell and Molecular Biology of Drugs, Faculty of Pharmacy, Comenius University, 83232 Bratislava, Slovakia
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9
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Mangini M, D’Angelo R, Vinciguerra C, Payré C, Lambeau G, Balestrieri B, Charles JF, Mariggiò S. Multimodal regulation of the osteoclastogenesis process by secreted group IIA phospholipase A 2. Front Cell Dev Biol 2022; 10:966950. [PMID: 36105351 PMCID: PMC9467450 DOI: 10.3389/fcell.2022.966950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Accepted: 07/25/2022] [Indexed: 01/21/2023] Open
Abstract
Increasing evidence points to the involvement of group IIA secreted phospholipase A2 (sPLA2-IIA) in pathologies characterized by abnormal osteoclast bone-resorption activity. Here, the role of this moonlighting protein has been deepened in the osteoclastogenesis process driven by the RANKL cytokine in RAW264.7 macrophages and bone-marrow derived precursor cells from BALB/cJ mice. Inhibitors with distinct selectivity toward sPLA2-IIA activities and recombinant sPLA2-IIA (wild-type or catalytically inactive forms, full-length or partial protein sequences) were instrumental to dissect out sPLA2-IIA function, in conjunction with reduction of sPLA2-IIA expression using small-interfering-RNAs and precursor cells from Pla2g2a knock-out mice. The reported data indicate sPLA2-IIA participation in murine osteoclast maturation, control of syncytium formation and resorbing activity, by mechanisms that may be both catalytically dependent and independent. Of note, these studies provide a more complete understanding of the still enigmatic osteoclast multinucleation process, a crucial step for bone-resorbing activity, uncovering the role of sPLA2-IIA interaction with a still unidentified receptor to regulate osteoclast fusion through p38 SAPK activation. This could pave the way for the design of specific inhibitors of sPLA2-IIA binding to interacting partners implicated in osteoclast syncytium formation.
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Affiliation(s)
- Maria Mangini
- Institute of Protein Biochemistry, National Research Council, Naples, Italy
| | - Rosa D’Angelo
- Institute of Protein Biochemistry, National Research Council, Naples, Italy
| | - Caterina Vinciguerra
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Christine Payré
- Centre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, Université Côte d’Azur, Valbonne Sophia Antipolis, France
| | - Gérard Lambeau
- Centre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, Université Côte d’Azur, Valbonne Sophia Antipolis, France
| | - Barbara Balestrieri
- Jeff and Penny Vinik Center for Translational Immunology Research, Department of Medicine, Division of Allergy and Clinical Immunology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Julia F. Charles
- Departments of Orthopaedic Surgery and Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Stefania Mariggiò
- Institute of Protein Biochemistry, National Research Council, Naples, Italy,*Correspondence: Stefania Mariggiò,
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10
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Petan T, Manček-Keber M. Half is enough: Oxidized lysophospholipids as novel bioactive molecules. Free Radic Biol Med 2022; 188:351-362. [PMID: 35779690 DOI: 10.1016/j.freeradbiomed.2022.06.228] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 06/01/2022] [Accepted: 06/13/2022] [Indexed: 10/17/2022]
Abstract
Studies in the last decade have established the roles of oxidized phospholipids as modulators of various cellular processes, from inflammation and immunity to cell death. Oxidized lysophospholipids, formed through the activity of phospholipases and oxidative enzymes and lacking an acyl chain in comparison with parent phospholipids, are now emerging as novel bioactive lipid mediators. Their detection and structural characterization have been limited in the past due to low amounts and the complexity of their biosynthetic and removal pathways, but recent studies have unequivocally demonstrated their formation under inflammatory conditions. The involvement of oxidized lysophospholipids in immune regulation classifies them as damage-associated molecular patterns (DAMPs), which can promote sterile inflammation and contribute to autoimmune and chronic diseases as well as aging-related diseases. Their signaling pathways are just beginning to be revealed. As the first publications indicate that oxidized lysophospholipids use the same receptors as pathogen-associated molecular patterns (PAMPs), it is likely that the inhibition of signaling pathways activated by oxidized lysophospholipids would affect innate immunity per se. On the other hand, inhibition or modulation of their enzymatic formation, which would not interfere with the response to pathogens, might be beneficial and is potentially a promising new field of research.
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Affiliation(s)
- Toni Petan
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, 1000, Ljubljana, Slovenia.
| | - Mateja Manček-Keber
- Department of Synthetic Biology and Immunology, National Institute of Chemistry, 1000, Ljubljana, Slovenia.
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11
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Sinapicacid Inhibits Group IIA Secretory Phospholipase A2 and Its Inflammatory Response in Mice. Antioxidants (Basel) 2022; 11:antiox11071251. [PMID: 35883742 PMCID: PMC9312209 DOI: 10.3390/antiox11071251] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 06/13/2022] [Accepted: 06/22/2022] [Indexed: 02/04/2023] Open
Abstract
Human Group IIA secreted phospholipase A2 (sPLA2-IIA) enzyme plays a crucial role in several chronic inflammatory diseases such asasthma, atherosclerosis, gout, bronchitis, etc. Several studies showed that the antioxidants exert an anti-inflammatory function by inhibiting the sPLA2-IIA enzyme. Hence, the present study evaluated an antioxidant molecule, sinapic acid, for sPLA2-IIA inhibition as an anti-inflammatory function. Initially, the antioxidant efficacy of sinapic acid was evaluated, and it showed greater antioxidant potency. Further, sinapic acid inhibited 94.4 ± 4.83% of sPLA2-IIA activity with an IC50 value of 4.16 ± 0.13 µM. The mode of sPLA2-IIA inhibition was examined by increasing the substrate concentration from 30 to 120nM and the calcium concentration from 2.5 to 15 mM, which did not change the level of inhibition. Further, sinapic acid altered the intrinsic fluorescence and distorted the far UltraViolet Circular Dichroism (UV-CD) spectra of the sPLA2-IIA, indicating the direct enzyme-inhibitor interaction. Sinapic acid reduced the sPLA2-IIA mediated hemolytic activity from 94 ± 2.19% to 12.35 ± 2.57% and mouse paw edema from 171.75 ± 2.2% to 114.8 ± 1.98%, demonstrating the anti-inflammatory efficiency of sinapic acid by in situ and in vivo methods, respectively. Finally, sinapic acid reduced the hemorrhagic effect of Vipera russelli venom hemorrhagic complex-I (VR-HC-I) as an anti-hemorrhagic function. Thus, the above experimental results revealed the sinapic acid potency to be an antioxidant, anti-inflammatory and anti-hemorrhagic molecule, and therefore, it appears to be a promising therapeutic agent.
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12
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El-Sayed NNE, Almaneai NM, Ben Bacha A, El-Ashrey MK, Al-Zaben MI, Almarhoon ZM. Biological Evaluation, Molecular Docking Analyses, and ADME Profiling of Certain New Quinazolinones as Anti-colorectal Agents. ACS OMEGA 2022; 7:18443-18458. [PMID: 35694504 PMCID: PMC9178606 DOI: 10.1021/acsomega.2c00812] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 04/29/2022] [Indexed: 06/15/2023]
Abstract
Colorectal carcinogenesis is a complex process, which is linked to dysregulation of human secretory phospholipases A2 (hsPLA2-G-IIA, hsPLA2-G-V, and hsPLA2-G-X), proteases (cathepsin-B, collagenase, thrombin, elastase, and trypsin), carbohydrate hydrolyzing enzymes (α-amylase and α-glucosidase), and free radical generating enzyme (xanthine oxidoreductase (XOR)). Therefore, some new quinazolinones were synthesized and evaluated as inhibitors against this array of enzymes as well as cytotoxic agents on LoVo and HCT-116 cells of colorectal cancer. Compounds 3g, 10, 8, 3c, and 1c exhibited promising cytotoxic effects with IC50 values ranging from 206.07 to 459.79 μM. Nine compounds showed promising enzymatic inhibitory effects, 3b, 3d, 3f, 5, 1a, and 12 (α-amylase), 8 (thrombin, elastase and trypsin), 10 (hsPLA2-G-IIA and hsPLA2-G-V), and 3f (α-glucosidase and XOR). Therefore, the most active inhibitors, were subjected to validated molecular docking studies to identify their affinities and binding modes. The expected physicochemical and pharmacokinetic features of the active candidates, 1a, 1c, 3b, 3c, 3d, 3f, 3g, 5, 8, 10, and 12 were predicted using bioavailability radar charts and boiled-egg graphical representations along with the Lipinski rule of five filter. Collectively, these studies showed the significance of derivatives 1c, 3b, 3c, 3d, 8, 10, and 12 as lead scaffolds for further optimization to develop enzymes inhibitors and anti-colorectal agents.
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Affiliation(s)
- Nahed N. E. El-Sayed
- National
Organization for Drug Control and Research, Egyptian Drug Authority, 51 Wezaret El-Zerra Street, Giza 35521, Egypt
| | - Norah M. Almaneai
- Department
of Chemistry, College of Science, King Saud
University, P. O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Abir Ben Bacha
- Biochemistry
Department, College of Science, King Saud
University, P. O. Box 22452, Riyadh 11495, Saudi Arabia
- Laboratory
of Plant Biotechnology Applied to Crop Improvement, Faculty of Science
of Sfax, University of Sfax, Sfax 3038, Tunisia
| | - Mohamed K. El-Ashrey
- Pharmaceutical
Chemistry Department, Faculty of Pharmacy, Cairo University, Kasr Elini Street, Cairo 11562, Egypt
- Medicinal
Chemistry Department, Faculty of Pharmacy, King Salman International University, Ras-Sedr, South Sinai, Egypt
| | - Maha I. Al-Zaben
- Department
of Chemistry, College of Science, King Saud
University, P. O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Zainab M. Almarhoon
- Department
of Chemistry, College of Science, King Saud
University, P. O. Box 2455, Riyadh 11451, Saudi Arabia
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13
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Giresha AS, Urs D, Manjunatha JG, Sophiya P, Supreetha BH, Jayarama S, Dharmappa KK. Group IIA secreted phospholipase A 2 inhibition by elemolic acid as a function of anti-inflammatory activity. Sci Rep 2022; 12:7649. [PMID: 35538123 PMCID: PMC9087174 DOI: 10.1038/s41598-022-10950-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 04/15/2022] [Indexed: 11/23/2022] Open
Abstract
Human group IIA secreted phospholipase A2 (GIIA) is a key enzyme in inflammatory reactions, worsening the condition of several chronic inflammatory diseases. The natural inhibitors of GIIA potentially block the production of inflammatory mediators. In the present study, elemolic acid, a triterpenoid from Boswellia serrata inhibited the GIIA enzyme in a concentration-dependent manner with IC50 value of 5.70 ± 0.02 µM. The mode of GIIA inhibition was studied by increasing the concentration of the substrate from 30 to 120 nM, and calcium from 2.5 to 15 mM, the level of inhibition was not changed. The inhibitor-enzyme interaction was examined by fluorimetry and Circular Dichroism (CD) studies; elemolic acid altered intrinsic fluorescence intensity and shifted far UV- CD spectra of GIIA enzyme, suggesting the direct interaction with GIIA. Elemolic acid neutralized the GIIA mediated indirect hemolytic activity from 94.5 to 9.8% and reduced GIIA induced mouse paw edema from 171.75 to 113.68%. Elemolic acid also reduced the hemorrhagic effect of GIIA along with Vipera russelii neurotoxic non-enzymatic peptide -VNTx-II (VR-HC-I). Thus, the elemolic acid has been proven as a potent inhibitor of GIIA enzyme and modulated the GIIA induced inflammatory response by in situ and in vivo methods.
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Affiliation(s)
- Aladahalli S Giresha
- Inflammation Research Laboratory, Department of Studies and Research in Biochemistry, Mangalore University, Jnana Kaveri Post Graduate campus, Chikka Aluvara, Kodagu, 571232, India
| | - Deepadarshan Urs
- Inflammation Research Laboratory, Department of Studies and Research in Biochemistry, Mangalore University, Jnana Kaveri Post Graduate campus, Chikka Aluvara, Kodagu, 571232, India
| | - J G Manjunatha
- Department of Chemistry, FMKMC College Madikeri, Mangalore University Constituent College, Mangalore, Karnataka, 571201, India
| | - P Sophiya
- Inflammation Research Laboratory, Department of Studies and Research in Biochemistry, Mangalore University, Jnana Kaveri Post Graduate campus, Chikka Aluvara, Kodagu, 571232, India
| | - B H Supreetha
- Inflammation Research Laboratory, Department of Studies and Research in Biochemistry, Mangalore University, Jnana Kaveri Post Graduate campus, Chikka Aluvara, Kodagu, 571232, India
| | - Shankar Jayarama
- Department of Studies in Food Technology, Davangere University, Shivagangotri, Davangere, 577002, India
| | - K K Dharmappa
- Inflammation Research Laboratory, Department of Studies and Research in Biochemistry, Mangalore University, Jnana Kaveri Post Graduate campus, Chikka Aluvara, Kodagu, 571232, India.
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14
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Ivanušec A, Šribar J, Križaj I. Secreted Phospholipases A 2 - not just Enzymes: Revisited. Int J Biol Sci 2022; 18:873-888. [PMID: 35002531 PMCID: PMC8741859 DOI: 10.7150/ijbs.68093] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 12/02/2021] [Indexed: 12/18/2022] Open
Abstract
Secreted phospholipases A2 (sPLA2s) participate in a very broad spectrum of biological processes through their enzymatic activity and as ligands for membrane and soluble receptors. The physiological roles of sPLA2s as enzymes have been very well described, while their functions as ligands are still poorly known. Since the last overview of sPLA2-binding proteins (sPLA2-BPs) 10 years ago, several important discoveries have occurred in this area. New and more sensitive analytical tools have enabled the discovery of additional sPLA2-BPs, which are presented and critically discussed here. The structural diversity of sPLA2-BPs reveals sPLA2s as very promiscuous proteins, and we offer some structural explanations for this nature that makes these proteins evolutionarily highly advantageous. Three areas of physiological engagement of sPLA2-BPs have appeared most clearly: cellular transport and signalling, and regulation of the enzymatic activity of sPLA2s. Due to the multifunctionality of sPLA2s, they appear to be exceptional pharmacological targets. We reveal the potential to exploit interactions of sPLA2s with other proteins in medical terms, for the development of original diagnostic and therapeutic procedures. We conclude this survey by suggesting the priority questions that need to be answered.
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Affiliation(s)
- Adrijan Ivanušec
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia.,Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000 Ljubljana, Slovenia
| | - Jernej Šribar
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia
| | - Igor Križaj
- Department of Molecular and Biomedical Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia
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15
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Sadhu SP, Yarla NS, Pragada RR, Konduri P. Anti-inflammatory Activity of PLA 2 Inhibitory Saccharumoside-B. Antiinflamm Antiallergy Agents Med Chem 2022; 21:121-134. [PMID: 35362396 DOI: 10.2174/1871523021666220330143058] [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: 10/07/2021] [Revised: 01/25/2022] [Accepted: 02/16/2022] [Indexed: 11/22/2022]
Abstract
BACKGROUND Saccharumoside-B and its analogs were found to have anticancer potential in vitro. The present study reports acute toxicity, molecular docking, ADMET profile analysis, and in vitro and in vivo anti-inflammatory activity of saccharumoside-B for the first time. METHODS The in vitro enzyme inhibitory activity of saccharumoside-B on PLA2, COX-1, COX-2, and 5-LOX enzymes was evaluated by the cell-free method, and its effect on TNF-α, IL1β, and IL- 6 secretion levels in LPS stimulated THP-1 human monocytes was determined by ELISA-based methods. The anti-inflammatory activity was evaluated in vivo by carrageenan-induced rat paw edema model. To test its binding affinity at the active site pockets of PLA2 enzymes and assess drug-like properties, docking experiments and ADMET studies were performed. RESULTS Saccharumoside-B showed selective inhibition of the sPLA2 enzyme (IC50 = 7.53 ± 0.232 μM), and thioetheramide-PC was used as a positive control. It showed significant inhibition (P ≤ 0.05) of TNF-α, IL-1β, and IL-6 cytokines compared to the positive control dexamethasone. Saccharumoside-B showed a dose-dependent inhibition of carrageenan-induced rat paw edema, with a maximum inhibition (76.09 ± 0.75) observed at 3 hours after the phlogistic agent injection. Saccharumoside-B potentially binds to the active site pocket of sPLA2 crystal protein (binding energy -7.6 Kcal/Mol). It complies with Lipinski's Rule of Five, showing a promising safety profile. The bioactivity scores suggested it to be a better enzyme inhibitor. CONCLUSION Saccharumoside-B showed significant PLA2 inhibition. It can become a potential lead molecule in synthesizing a new class of selective PLA2 inhibitors with a high safety profile in the future.
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Affiliation(s)
- Surya Prabha Sadhu
- Department of AU College of Pharmaceutical Sciences and Pharmacology, Andhra University, Visakhapatnam, India
- Department of Pharmacology, Shri Vishnu College of Pharmacy, Bhimavaram, India
| | - Nagendra Sastry Yarla
- Department of Biochemistry, GITAM Institute of Science, GITAM University, Visakhapatnam, India
| | - Rajeswara Rao Pragada
- Department of AU College of Pharmaceutical Sciences, Pharmacology, Andhra University, Visakhapatnam, India
| | - Prasad Konduri
- Department of Pharmacology, Shri Vishnu College of Pharmacy, Bhimavaram, India
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16
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Scott KF, Mann TJ, Fatima S, Sajinovic M, Razdan A, Kim RR, Cooper A, Roohullah A, Bryant KJ, Gamage KK, Harman DG, Vafaee F, Graham GG, Church WB, Russell PJ, Dong Q, de Souza P. Human Group IIA Phospholipase A 2-Three Decades on from Its Discovery. Molecules 2021; 26:molecules26237267. [PMID: 34885848 PMCID: PMC8658914 DOI: 10.3390/molecules26237267] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 11/21/2021] [Accepted: 11/22/2021] [Indexed: 12/13/2022] Open
Abstract
Phospholipase A2 (PLA2) enzymes were first recognized as an enzyme activity class in 1961. The secreted (sPLA2) enzymes were the first of the five major classes of human PLA2s to be identified and now number nine catalytically-active structurally homologous proteins. The best-studied of these, group IIA sPLA2, has a clear role in the physiological response to infection and minor injury and acts as an amplifier of pathological inflammation. The enzyme has been a target for anti-inflammatory drug development in multiple disorders where chronic inflammation is a driver of pathology since its cloning in 1989. Despite intensive effort, no clinically approved medicines targeting the enzyme activity have yet been developed. This review catalogues the major discoveries in the human group IIA sPLA2 field, focusing on features of enzyme function that may explain this lack of success and discusses future research that may assist in realizing the potential benefit of targeting this enzyme. Functionally-selective inhibitors together with isoform-selective inhibitors are necessary to limit the apparent toxicity of previous drugs. There is also a need to define the relevance of the catalytic function of hGIIA to human inflammatory pathology relative to its recently-discovered catalysis-independent function.
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Affiliation(s)
- Kieran F. Scott
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia; (T.J.M.); (S.F.); (A.C.); (A.R.); (P.d.S.)
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
- Correspondence: ; Tel.: +61-2-8738-9026
| | - Timothy J. Mann
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia; (T.J.M.); (S.F.); (A.C.); (A.R.); (P.d.S.)
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
| | - Shadma Fatima
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia; (T.J.M.); (S.F.); (A.C.); (A.R.); (P.d.S.)
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
- School of Biotechnology and Biological Sciences, University of New South Wales (UNSW Sydney), Sydney, NSW 2052, Australia;
| | - Mila Sajinovic
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
| | - Anshuli Razdan
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
| | - Ryung Rae Kim
- School of Pharmacy, Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia; (R.R.K.); (W.B.C.)
| | - Adam Cooper
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia; (T.J.M.); (S.F.); (A.C.); (A.R.); (P.d.S.)
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
- Liverpool Cancer Therapy Centre, Liverpool Hospital, Liverpool, NSW 2170, Australia
| | - Aflah Roohullah
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia; (T.J.M.); (S.F.); (A.C.); (A.R.); (P.d.S.)
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
- Liverpool Cancer Therapy Centre, Liverpool Hospital, Liverpool, NSW 2170, Australia
| | - Katherine J. Bryant
- School of Photovoltaic and Renewable Energy Engineering, UNSW Sydney, Sydney, NSW 2052, Australia;
| | - Kasuni K. Gamage
- School of Science, Western Sydney University, Campbelltown, NSW 2560, Australia; (K.K.G.); (D.G.H.)
| | - David G. Harman
- School of Science, Western Sydney University, Campbelltown, NSW 2560, Australia; (K.K.G.); (D.G.H.)
| | - Fatemeh Vafaee
- School of Biotechnology and Biological Sciences, University of New South Wales (UNSW Sydney), Sydney, NSW 2052, Australia;
- UNSW Data Science Hub, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Garry G. Graham
- Department of Clinical Pharmacology, St Vincent’s Hospital Sydney, Darlinghurst, NSW 2010, Australia;
- School of Medical Sciences, UNSW Sydney, Sydney, NSW 2052, Australia
| | - W. Bret Church
- School of Pharmacy, Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia; (R.R.K.); (W.B.C.)
| | - Pamela J. Russell
- Australian Prostate Cancer Research Centre—QUT, Brisbane, QLD 4102, Australia;
| | - Qihan Dong
- Chinese Medicine Anti-Cancer Evaluation Program, Greg Brown Laboratory, Central Clinical School and Charles Perkins Centre, The University of Sydney, Sydney, NSW 2006, Australia;
| | - Paul de Souza
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia; (T.J.M.); (S.F.); (A.C.); (A.R.); (P.d.S.)
- Ingham Institute of Applied Medical Research, Liverpool, NSW 2170, Australia; (M.S.); (A.R.)
- School of Medicine, UNSW Sydney, Sydney, NSW 2052, Australia
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Kitsiouli E, Tenopoulou M, Papadopoulos S, Lekka ME. Phospholipases A2 as biomarkers in ARDS. Biomed J 2021; 44:663-670. [PMID: 34478892 PMCID: PMC8847824 DOI: 10.1016/j.bj.2021.08.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 07/16/2021] [Accepted: 08/23/2021] [Indexed: 02/06/2023] Open
Abstract
Acute respiratory distress syndrome (ARDS) is a multifactorial life-threatening lung injury, characterized by diffuse lung inflammation and increased alveolocapillary barrier permeability. The different stages of ARDS have distinctive biochemical and clinical profiles. Despite the progress of our understanding on ARDS pathobiology, the mechanisms underlying its pathogenesis are still obscure. Herein, we review the existing literature about the implications of phospholipases 2 (PLA2s), a large family of enzymes that catalyze the hydrolysis of fatty acids at the sn-2 position of glycerophospholipids, in ARDS-related pathology. We emphasize on the versatile way of participation of different PLA2s isoforms in the distinct ARDS subgroup phenotypes by either potentiating lung inflammation and damage or by preserving the normal lung. Current research supports that PLA2s are associated with the progression and the outcome of ARDS. We herein discuss the transcellular communication of PLA2s through secreted extracellular vesicles and suggest it as a new mechanism of PLA2s involvement in ARDS. Thus, the elucidation of the spatiotemporal features of PLA2s expression may give new insights and provide valuable information about the risk of an individual to develop ARDS or advance to more severe stages, and potentially identify PLA2 isoforms as biomarkers and target for pharmacological intervention.
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Affiliation(s)
- Eirini Kitsiouli
- Laboratory of Biochemistry, Department of Chemistry, University of Ioannina, Ioannina, Greece
| | - Margarita Tenopoulou
- Laboratory of Biochemistry, Department of Chemistry, University of Ioannina, Ioannina, Greece
| | - Stylianos Papadopoulos
- Laboratory of Biochemistry, Department of Chemistry, University of Ioannina, Ioannina, Greece
| | - Marilena E Lekka
- Laboratory of Biochemistry, Department of Chemistry, University of Ioannina, Ioannina, Greece.
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18
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A Representative GIIA Phospholipase A 2 Activates Preadipocytes to Produce Inflammatory Mediators Implicated in Obesity Development. Biomolecules 2020; 10:biom10121593. [PMID: 33255269 PMCID: PMC7760919 DOI: 10.3390/biom10121593] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 11/15/2020] [Accepted: 11/18/2020] [Indexed: 12/27/2022] Open
Abstract
Adipose tissue secretes proinflammatory mediators which promote systemic and adipose tissue inflammation seen in obesity. Group IIA (GIIA)-secreted phospholipase A2 (sPLA2) enzymes are found to be elevated in plasma and adipose tissue from obese patients and are active during inflammation, generating proinflammatory mediators, including prostaglandin E2 (PGE2). PGE2 exerts anti-lipolytic actions and increases triacylglycerol levels in adipose tissue. However, the inflammatory actions of GIIA sPLA2s in adipose tissue cells and mechanisms leading to increased PGE2 levels in these cells are unclear. This study investigates the ability of a representative GIIA sPLA2, MT-III, to activate proinflammatory responses in preadipocytes, focusing on the biosynthesis of prostaglandins, adipocytokines and mechanisms involved in these effects. Our results showed that MT-III induced biosynthesis of PGE2, PGI2, MCP-1, IL-6 and gene expression of leptin and adiponectin in preadipocytes. The MT-III-induced PGE2 biosynthesis was dependent on cytosolic PLA2 (cPLA2)-α, cyclooxygenases (COX)-1 and COX-2 pathways and regulated by a positive loop via the EP4 receptor. Moreover, MT-III upregulated COX-2 and microsomal prostaglandin synthase (mPGES)-1 protein expression. MCP-1 biosynthesis induced by MT-III was dependent on the EP4 receptor, while IL-6 biosynthesis was dependent on EP3 receptor engagement by PGE2. These data highlight preadipocytes as targets for GIIA sPLA2s and provide insight into the roles played by this group of sPLA2s in obesity.
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