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Çomaklı S, Küçükler S, Değirmençay Ş, Bolat İ, Özdemir S. Quinacrine, a PLA2 inhibitor, alleviates LPS-induced acute kidney injury in rats: Involvement of TLR4/NF-κB/TNF α-mediated signaling. Int Immunopharmacol 2024; 126:111264. [PMID: 38016342 DOI: 10.1016/j.intimp.2023.111264] [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: 09/19/2023] [Revised: 10/30/2023] [Accepted: 11/16/2023] [Indexed: 11/30/2023]
Abstract
Acute Kidney Injury (AKI) is a major factor in sepsis-related mortality and may occur due to lipopolysaccharide (LPS), an endotoxin produced by gram-negative bacteria that triggers a systemic acute inflammatory response. Quinacrine's (QC) renoprotective properties in sepsis and the underlying mechanism, however, are still not fully understood. This study was done to investigate the anti-inflammatory, antioxidative, and anti-apoptotic effects of QC, a phospholipase A2 (PLA2) inhibitor, against LPS-induced AKI. Rats were randomly divided into five groups: control group, QC30 group, LPS group, LPS+QC 10 group, and LPS+QC 30 group. The rats were administered intraperitoneally QC (10 and 30 mg/kg) for 3 days (once a day) prior to injection of LPS (3 mg/kg). Six hours after the LPS injection, the histopathological changes, oxidative stress, inflammation, and apoptosis in the collected kidney tissues were detected by hematoxylin and eosin staining, enzyme-linked immunosorbent assay (ELISA), real-time PCR (RT-PCR), and immunohistochemistry staining, respectively. QC pretreatment could successfully attenuate LPS-induced AKI, as evidenced by a decrease in tissue histopathological injury. Meanwhile, QC alleviated LPS-induced kidney oxidative stress; it reduced MDA levels and increased levels of SOD, CAT, GPX, and GSH. LPS-induced elevations in kidney TLR4, NF-κB, TNF-α, IL-1β, IL-6, PLA2, caspase 3, and Bax contents were significantly attenuated in QC-treated groups. Our findings revealed a significant effect of QC: protecting against LPS-induced AKI through inhibition of PLA2 and decreasing inflammation, oxidative stress, and apoptosis. To treat LPS-induced AKI, QC may be an effective substance with an excellent protection profile.
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Affiliation(s)
- Selim Çomaklı
- Department of Pathology, Faculty of Veterinary Medicine, Atatürk University, Erzurum, Turkey.
| | - Sefa Küçükler
- Department of Biochemistry, Faculty of Veterinary Medicine, Atatürk University, Erzurum, Turkey.
| | - Şükrü Değirmençay
- Department of Internal Medicine, Faculty of Veterinary Medicine, Atatürk University, Erzurum, Turkey.
| | - İsmail Bolat
- Department of Pathology, Faculty of Veterinary Medicine, Atatürk University, Erzurum, Turkey.
| | - Selçuk Özdemir
- Department of Genetics, Faculty of Veterinary Medicine, Atatürk University, Erzurum, Turkey; German Center for Neurodegenerative Diseases, DZNE, Bonn, Germany.
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2
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Mechanism of oxidized phospholipid-related inflammatory response in vascular ageing. Ageing Res Rev 2023; 86:101888. [PMID: 36806379 DOI: 10.1016/j.arr.2023.101888] [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: 11/21/2022] [Revised: 02/05/2023] [Accepted: 02/16/2023] [Indexed: 02/20/2023]
Abstract
Vascular ageing is an important factor in the morbidity and mortality of the elderly. Atherosclerosis is a characteristic disease of vascular ageing, which is closely related to the enhancement of vascular inflammation. Phospholipid oxidation products are important factors in inducing cellular inflammation. Through interactions with vascular cells and immune cells, they regulate intracellular signaling pathways, activate the expression of various cytokines, and affect cell behavior, such as metabolic level, proliferation, apoptosis, etc. Intervention in lipid metabolism and anti-inflammation are the two key pathways of drugs for the treatment of atherosclerosis. This review aims to sort out the signaling pathway of oxidized phospholipids-induced inflammatory factors in vascular cells and immune cells and the mechanism leading to changes in cell behavior, and summarize the therapeutic targets in the inflammatory signaling pathway for the development of atherosclerosis drugs.
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Jayachandra K, Gowda MDM, Rudresha GV, Manjuprasanna VN, Urs AP, Nandana MB, Bharatha M, Jameel NM, Vishwanath BS. Inhibition of sPLA 2 enzyme activity by cell-permeable antioxidant EUK-8 and downregulation of p38, Akt, and p65 signals induced by sPLA 2 in inflammatory mouse paw edema model. J Cell Biochem 2023; 124:294-307. [PMID: 36585945 DOI: 10.1002/jcb.30366] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 11/24/2022] [Accepted: 12/19/2022] [Indexed: 01/01/2023]
Abstract
The arachidonic acid (AA) metabolic pathway, plays a vital role in the production of eicosanoids by the action of pro-inflammatory secretory phospholipase A2 (PLA2 ). Release of eicosanoids is known to be involved in many inflammatory diseases. Identification of the inhibitory molecules of this AA pathway enzyme along with the regulation of intracellular signaling cascades may be a finer choice to develop as a powerful anti-inflammatory drug. In this regard, we have screened few cell-permeable antioxidant molecules Tempo, Mito-TEMPO, N,N'-Bis(salicylideneamino)ethane-manganese(II) (EUK)-134, and EUK-8 against pro-inflammatory sPLA2 s. Among these, we found EUK-8 is a potent inhibitor with its IC50 value ranges 0.7-2.0 µM for sPLA2 s isolated from different sources. Furthermore, docking studies confirm the strong binding of EUK-8 towards sPLA2 . In vivo effect of EUK-8 was studied in HSF-sPLA2 -induced edema in mouse paw model. In addition to neutralizing the edema, EUK-8 significantly reduces the phosphorylation level of inflammatory proteins such as p38 member of MAPK pathway, Akt, and p65 along with the suppression of pro-inflammatory cytokine (interleukin-6) and chemokine (CXCL1) in edematous tissue. This shows that EUK-8 not only inhibits the sPLA2 activity, it also plays an important role in the regulation of sPLA2 -induced cell signaling cascades. Apart from the sPLA2 inhibition, we also examine the regulatory actions of EUK-8 with other downstream enzymes of AA pathway such as 5-LOX assay in human polymorphonuclear leukocytes (PMNs) and COX-2 expression in carrageenan-λ induced paw edema. Here EUK-8 significantly inhibits 5-LOX enzyme activity and downregulates COX-2 expression. These data indicate that EUK-8 found to be a promising multitargeted inhibitory molecule toward inflammatory pathway. In conclusion, mitochondrial targeted antioxidant EUK-8 is not only the powerful antioxidant, also a potent anti-inflammatory molecule and may be a choice of molecule for pharmacological applications.
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Affiliation(s)
- Krishnegowda Jayachandra
- Department of Studies in Biochemistry, University of Mysore, Manasagangotri, Mysuru, Karnataka, India
| | - M D Milan Gowda
- Department of Studies in Biochemistry, University of Mysore, Manasagangotri, Mysuru, Karnataka, India
| | - Gotravalli V Rudresha
- Evolutionary Venomics Lab, Centre for Ecological Sciences, Indian Institute of Science, Bengaluru, Karnataka, India
| | | | - Amog P Urs
- Comprehensive Cancer Centre, The Ohio State University, Columbus, Ohio, USA
| | | | - Madeva Bharatha
- Department of Studies in Biochemistry, University of Mysore, Manasagangotri, Mysuru, Karnataka, India
| | - Noor Mohamed Jameel
- Department of Studies in Biochemistry, University of Mysore, Manasagangotri, Mysuru, Karnataka, India
| | - Bannikuppe S Vishwanath
- Department of Studies in Biochemistry, University of Mysore, Manasagangotri, Mysuru, Karnataka, India
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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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Murray TE, Richards CM, Robert-Gostlin VN, Bernath AK, Lindhout IA, Klegeris A. Potential neurotoxic activity of diverse molecules released by astrocytes. Brain Res Bull 2022; 189:80-101. [PMID: 35988785 DOI: 10.1016/j.brainresbull.2022.08.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 07/04/2022] [Accepted: 08/14/2022] [Indexed: 11/02/2022]
Abstract
Astrocytes are the main support cells of the central nervous system. They also participate in neuroimmune reactions. In response to pathological and immune stimuli, astrocytes transform to reactive states characterized by increased release of inflammatory mediators. Some of these molecules are neuroprotective and inflammation resolving while others, including reactive oxygen species (ROS), nitric oxide (NO), matrix metalloproteinase (MMP)- 9, L-glutamate, and tumor necrosis factor α (TNF), are well-established toxins known to cause damage to surrounding cells and tissues. We hypothesized that similar to microglia, the brain immune cells, reactive astrocytes can release a broader set of diverse molecules that are potentially neurotoxic. A literature search was conducted to identify such molecules using the following two criteria: 1) evidence of their expression and secretion by astrocytes and 2) direct neurotoxic action. This review describes 14 structurally diverse molecules as less-established astrocyte neurotoxins, including C-X-C motif chemokine ligand (CXCL)10, CXCL12/CXCL12(5-67), FS-7-associated surface antigen ligand (FasL), macrophage inflammatory protein (MIP)- 2α, TNF-related apoptosis inducing ligand (TRAIL), pro-nerve growth factor (proNGF), pro-brain-derived neurotrophic factor (proBDNF), chondroitin sulfate proteoglycans (CSPGs), cathepsin (Cat)B, group IIA secretory phospholipase A2 (sPLA2-IIA), amyloid beta peptides (Aβ), high mobility group box (HMGB)1, ceramides, and lipocalin (LCN)2. For some of these molecules, further studies are required to establish either their direct neurotoxic effects or the full spectrum of stimuli that induce their release by astrocytes. Only limited studies with human-derived astrocytes and neurons are available for most of these potential neurotoxins, which is a knowledge gap that should be addressed in the future. We also summarize available evidence of the role these molecules play in select neuropathologies where reactive astrocytes are a key feature. A comprehensive understanding of the full spectrum of neurotoxins released by reactive astrocytes is key to understanding neuroinflammatory diseases characterized by the adverse activation of these cells and may guide the development of novel treatment strategies.
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Affiliation(s)
- Taryn E Murray
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia V1V 1V7, Canada
| | - Christy M Richards
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia V1V 1V7, Canada
| | - Victoria N Robert-Gostlin
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia V1V 1V7, Canada
| | - Anna K Bernath
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia V1V 1V7, Canada
| | - Ivan A Lindhout
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia V1V 1V7, Canada
| | - Andis Klegeris
- Department of Biology, University of British Columbia Okanagan Campus, Kelowna, British Columbia V1V 1V7, Canada.
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Hussein MA, Ismail NEM, Mohamed AH, Borik RM, Ali AA, Mosaad YO. Plasma Phospholipids: A Promising Simple Biochemical Parameter to Evaluate COVID-19 Infection Severity. Bioinform Biol Insights 2021; 15:11779322211055891. [PMID: 34840499 PMCID: PMC8619733 DOI: 10.1177/11779322211055891] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 10/10/2021] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Coronavirus-19 (COVID-19) pandemic is a worldwide public health problem that has been known in China since December 25, 2019. Phospholipids are structural components of the mammalian cytoskeleton and cell membranes. They suppress viral attachment to the plasma membrane and subsequent replication in lung cells. In the virus-infected lung, phospholipids are highly prone to oxidation by reactive oxygen species, leading to the production of oxidized phospholipids (OxPLs). OBJECTIVE This study was carried out to explain the correlation between the level of plasma phospholipids in patients with COVID-19 infection and the levels of cytokine storms to assess the severity of the disease. METHODS Plasma samples from 34 enrolled patients with mild, moderate, and severe COVID-19 infection were collected. Complete blood count (CBC), plasma levels of D-dimer, ferritin, C-reactive protein (CRP), cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), phospholipids, secretory phospholipase A2 (sPLA2)α2, and cytokine storms were estimated, and lung computed tomography (CT) imaging was detected. RESULTS The CBC picture showed the presence of leukopenia, lymphopenia, and eosinopenia in patients with COVID-19 infection. Furthermore, a significant increase was found in plasma levels of D-dimer, CRP, ferritin, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-13 as well as sPLA2α2 activity compared to normal persons. However, plasma levels of phospholipids decreased in patients with moderate and severe COVID-19 infection, as well as significantly decreased in levels of triacylglycerols and HDL-C in plasma from patients with severe infection only, compared to normal persons. Furthermore, a lung CT scan showed the presence of inflammation in a patient with mild, moderate, and severe COVID-19 infection. CONCLUSIONS This study shows that there is a correlation between plasma phospholipid depletion and elevated cytokine storm in patients with COVID-19 infection. Depletion of plasma phospholipid levels in patients with COVID-19 infection is due to oxidative stress, induction of cytokine storm, and systemic inflammatory response after endothelial cell damage promote coagulation. According to current knowledge, patients with COVID-19 infection may need to administer surfactant replacement therapy and sPLA2 inhibitors to treat respiratory distress syndrome, which helps them to maintain the interconnected surfactant structures.
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Affiliation(s)
- Mohammed Abdalla Hussein
- Department of Biochemistry, Faculty of Applied Medical Science, October 6 University, 6th of October City, Egypt
| | | | - Ahmed H Mohamed
- Department of Radiology and Medical Imaging, Faculty of Applied Medical Science, October 6 University, 6th of October City, Egypt
| | - Rita M Borik
- Chemistry Department, Faculty of Science (Female Section), Jazan University, Jazan, Saudi Arabia
| | | | - Yasser O Mosaad
- Faculty of Pharmacy, Department of Pharmacology, Toxicology, and Biochemistry, Future University, New Cairo, Egypt
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7
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Wei Y, Asbell PA. sPLA 2-IIa participates in ocular surface inflammation in humans with dry eye disease. Exp Eye Res 2020; 201:108209. [PMID: 33011237 DOI: 10.1016/j.exer.2020.108209] [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: 11/01/2019] [Revised: 08/21/2020] [Accepted: 08/30/2020] [Indexed: 11/16/2022]
Abstract
PURPOSE To determine the roles of secretory phospholipase A2-IIa (sPLA2-IIa) in the inflammatory responses of the compromised ocular surface. METHODS Conjunctival impression cytology (IC) samples and tears were collected from patients with mild to severe non-Sjogren's dry eye disease (DED) and normal controls. The IC samples were analyzed for transcription of sPLA2-IIa and inflammatory cytokine/chemokine genes using quantitative real-time RT-PCR (qRT2-PCR) and pathway-focus PCR-array. The tear samples were analyzed for 13 inflammatory cytokines and chemokines with Millipore 13-Plex kit. Finally, sPLA2-IIa-treated human conjunctival epithelial cell (HCjE) cultures were analyzed with a pathway-focused PCR array. RESULTS Transcription of sPLA2-IIa was significantly increased in severe DED patients as compared to those of mild DED patients and normal controls. The transcription of inflammatory cytokines (IL-1β, IL-4, IL-6, IL-17, TNF-α, IFN-γ), chemokines (IL-8, CXCL10, CXCL11, CXCL-14, CCR6, LTB) and matrix metalloproteinase 9 (MMP9) were simultaneously increased in the same IC samples of DED. Concentrations of IL-6 and IL-8 in tears were significantly higher in DED patients than those of the controls and positively correlated to DED severity scores. On the other hand, IL-2, IL-4, IL-10, IL-12 and IFN-γ were significantly lower in DED patients than those in the controls and inversely correlated to DEWS scores. Single treatment of sPLA2-IIa, IL-1β or TNF-α of HCjE cells induced minimal to no PGE2 production. When sPLA2-IIa was added to HCjE cells that were pre-treated with pro-inflammatory cytokines (TNF-α or IL-1β), significant stimulation of PGE2 production was observed, concurrent with the extensive transcriptional changes of many inflammatory cytokines/chemokines and their receptors. CONCLUSION sPLA2-IIa activity was elevated and not only associated with inflammatory changes in DED patient samples, but was also found to cooperate with TNF- α and IL-1β to induce inflammatory response in human conjunctival epithelial cells. Understanding the roles of sPLA2-IIa in ocular surface inflammation may lead to better strategies for the treatment of chronic inflammation associated with DED and other ocular inflammatory conditions.
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Affiliation(s)
- Y Wei
- Department Ophthalmology, The Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA; Department Ophthalmology, Hamilton Eye Institute, College of Medicine, University of Tennessee, Memphis, TN, 38163, USA.
| | - P A Asbell
- Department Ophthalmology, The Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA; Department Ophthalmology, Hamilton Eye Institute, College of Medicine, University of Tennessee, Memphis, TN, 38163, USA
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8
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Stien D, Suzuki M, Rodrigues AMS, Yvin M, Clergeaud F, Thorel E, Lebaron P. A unique approach to monitor stress in coral exposed to emerging pollutants. Sci Rep 2020; 10:9601. [PMID: 32541793 PMCID: PMC7295770 DOI: 10.1038/s41598-020-66117-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 04/15/2020] [Indexed: 11/29/2022] Open
Abstract
Metabolomic profiling of the hexacoral Pocillopora damicornis exposed to solar filters revealed a metabolomic signature of stress in this coral. It was demonstrated that the concentration of the known steroid (3β, 5α, 8α) -5, 8-epidioxy- ergosta- 6, 24(28) - dien- 3- ol (14) increased in response to octocrylene (OC) and ethylhexyl salicylate (ES) at 50 µg/L. Based on the overall coral response, we hypothesize that steroid 14 mediates coral response to stress. OC also specifically altered mitochondrial function at this concentration and above, while ES triggered a stress/inflammatory response at 300 µg/L and above as witnessed by the significant increases in the concentrations of polyunsaturated fatty acids, lysophosphatidylcholines and lysophosphatidylethanolamines. Benzophenone-3 increased the concentration of compound 14 at 2 mg/L, while the concentration of stress marker remained unchanged upon exposition to the other solar filters tested. Also, our results seemed to refute earlier suggestions that platelet-activating factor is involved in the coral inflammatory response.
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Affiliation(s)
- Didier Stien
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France.
| | - Marcelino Suzuki
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France
| | - Alice M S Rodrigues
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France
| | - Marion Yvin
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France
| | - Fanny Clergeaud
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France
| | - Evane Thorel
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France
| | - Philippe Lebaron
- Sorbonne Université, CNRS, Laboratoire de Biodiversité et Biotechnologies Microbiennes, USR3579, Observatoire Océanologique, 66650, Banyuls-sur-mer, France
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Rodríguez JP, Leiguez E, Guijas C, Lomonte B, Gutiérrez JM, Teixeira C, Balboa MA, Balsinde J. A Lipidomic Perspective of the Action of Group IIA Secreted Phospholipase A 2 on Human Monocytes: Lipid Droplet Biogenesis and Activation of Cytosolic Phospholipase A 2α. Biomolecules 2020; 10:biom10060891. [PMID: 32532115 PMCID: PMC7355433 DOI: 10.3390/biom10060891] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/08/2020] [Accepted: 06/10/2020] [Indexed: 12/14/2022] Open
Abstract
Phospholipase A2s constitute a wide group of lipid-modifying enzymes which display a variety of functions in innate immune responses. In this work, we utilized mass spectrometry-based lipidomic approaches to investigate the action of Asp-49 Ca2+-dependent secreted phospholipase A2 (sPLA2) (MT-III) and Lys-49 sPLA2 (MT-II), two group IIA phospholipase A2s isolated from the venom of the snake Bothrops asper, on human peripheral blood monocytes. MT-III is catalytically active, whereas MT-II lacks enzyme activity. A large decrease in the fatty acid content of membrane phospholipids was detected in MT III-treated monocytes. The significant diminution of the cellular content of phospholipid-bound arachidonic acid seemed to be mediated, in part, by the activation of the endogenous group IVA cytosolic phospholipase A2α. MT-III triggered the formation of triacylglycerol and cholesterol enriched in palmitic, stearic, and oleic acids, but not arachidonic acid, along with an increase in lipid droplet synthesis. Additionally, it was shown that the increased availability of arachidonic acid arising from phospholipid hydrolysis promoted abundant eicosanoid synthesis. The inactive form, MT-II, failed to produce any of the effects described above. These studies provide a complete lipidomic characterization of the monocyte response to snake venom group IIA phospholipase A2, and reveal significant connections among lipid droplet biogenesis, cell signaling and biochemical pathways that contribute to initiating the inflammatory response.
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Affiliation(s)
- Juan P. Rodríguez
- Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Valladolid, 47003 Valladolid, Spain; (J.P.R.); (E.L.); (C.G.); (M.A.B.)
- Laboratorio de Investigaciones Bioquímicas de la Facultad de Medicina (LIBIM), Instituto de Química Básica y Aplicada del Nordeste Argentino (IQUIBA-NEA), Universidad Nacional del Nordeste, Consejo Nacional de Investigaciones Científicas y Técnicas (UNNE-CONICET), Corrientes 3400, Argentina
| | - Elbio Leiguez
- Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Valladolid, 47003 Valladolid, Spain; (J.P.R.); (E.L.); (C.G.); (M.A.B.)
- Laboratorio de Farmacologia, Instituto Butantan, Sao Paulo 01000, Brazil;
| | - Carlos Guijas
- Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Valladolid, 47003 Valladolid, Spain; (J.P.R.); (E.L.); (C.G.); (M.A.B.)
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain
| | - Bruno Lomonte
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José 11501–2060, Costa Rica; (B.L.); (J.M.G.)
| | - José M. Gutiérrez
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José 11501–2060, Costa Rica; (B.L.); (J.M.G.)
| | - Catarina Teixeira
- Laboratorio de Farmacologia, Instituto Butantan, Sao Paulo 01000, Brazil;
| | - María A. Balboa
- Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Valladolid, 47003 Valladolid, Spain; (J.P.R.); (E.L.); (C.G.); (M.A.B.)
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain
| | - Jesús Balsinde
- Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Valladolid, 47003 Valladolid, Spain; (J.P.R.); (E.L.); (C.G.); (M.A.B.)
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), 28029 Madrid, Spain
- Correspondence: ; Tel.: +34-983-423-062
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10
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van Hensbergen VP, Wu Y, van Sorge NM, Touqui L. Type IIA Secreted Phospholipase A2 in Host Defense against Bacterial Infections. Trends Immunol 2020; 41:313-326. [PMID: 32151494 DOI: 10.1016/j.it.2020.02.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 02/07/2020] [Accepted: 02/08/2020] [Indexed: 12/13/2022]
Abstract
The enzyme type IIA secreted phospholipase A2 (sPLA2-IIA) is crucial for mammalian innate host defense against bacterial pathogens. Most studies have investigated the role of sPLA2-IIA in systemic bacterial infections, identifying molecular pathways of bacterial resistance against sPLA2-IIA-mediated killing, and providing insight into sPLA2-IIA mechanisms of action. Sensitization of (antibiotic-resistant) bacteria to sPLA2-IIA action by blocking bacterial resistance or by applying sPLA2-IIA to treat bacterial infections might represent a therapeutic option in the future. Because sPLA2-IIA is highly expressed at mucosal barriers, we also discuss how sPLA2-IIA is likely to be an important driver of microbiome composition; we anticipate that future research in this area may bring new insights into the role of sPLA2-IIA in health and disease.
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Affiliation(s)
- Vincent P van Hensbergen
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Yongzheng Wu
- Unité de Biologie Cellulaire de l'infection Microbienne, CNRS UMR3691, Institut Pasteur, Paris, France
| | - Nina M van Sorge
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands.
| | - Lhousseine Touqui
- Mucoviscidose et Bronchopathies Chroniques, département Santé Globale; Pasteur Institute, Paris, France.
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11
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Nelson AJ, Stephenson DJ, Cardona CL, Lei X, Almutairi A, White TD, Tusing YG, Park MA, Barbour SE, Chalfant CE, Ramanadham S. Macrophage polarization is linked to Ca 2+-independent phospholipase A 2β-derived lipids and cross-cell signaling in mice. J Lipid Res 2019; 61:143-158. [PMID: 31818877 DOI: 10.1194/jlr.ra119000281] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 11/27/2019] [Indexed: 12/27/2022] Open
Abstract
Phospholipases A2 (PLA2s) catalyze hydrolysis of the sn-2 substituent from glycerophospholipids to yield a free fatty acid (i.e., arachidonic acid), which can be metabolized to pro- or anti-inflammatory eicosanoids. Macrophages modulate inflammatory responses and are affected by Ca2+-independent phospholipase A2 (PLA2)β (iPLA2β). Here, we assessed the link between iPLA2β-derived lipids (iDLs) and macrophage polarization. Macrophages from WT and KO (iPLA2β-/-) mice were classically M1 pro-inflammatory phenotype activated or alternatively M2 anti-inflammatory phenotype activated, and eicosanoid production was determined by ultra-performance LC ESI-MS/MS. As a genotypic control, we performed similar analyses on macrophages from RIP.iPLA2β.Tg mice with selective iPLA2β overexpression in β-cells. Compared with WT, generation of select pro-inflammatory prostaglandins (PGs) was lower in iPLA2β-/- , and that of a specialized pro-resolving lipid mediator (SPM), resolvin D2, was higher; both changes are consistent with the M2 phenotype. Conversely, macrophages from RIP.iPLA2β.Tg mice exhibited an opposite landscape, one associated with the M1 phenotype: namely, increased production of pro-inflammatory eicosanoids (6-keto PGF1α, PGE2, leukotriene B4) and decreased ability to generate resolvin D2. These changes were not linked with secretory PLA2 or cytosolic PLA2α or with leakage of the transgene. Thus, we report previously unidentified links between select iPLA2β-derived eicosanoids, an SPM, and macrophage polarization. Importantly, our findings reveal for the first time that β-cell iPLA2β-derived signaling can predispose macrophage responses. These findings suggest that iDLs play critical roles in macrophage polarization, and we posit that they could be targeted therapeutically to counter inflammation-based disorders.
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Affiliation(s)
- Alexander J Nelson
- Department of Cell, Developmental, and Integrative Biology University of Alabama at Birmingham, Birmingham, AL 35294.,Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Daniel J Stephenson
- Department of Cell Biology, Microbiology, and Molecular Biology (CMMB), University of South Florida, Tampa, FL 33620
| | - Christopher L Cardona
- Department of Cell Biology, Microbiology, and Molecular Biology (CMMB), University of South Florida, Tampa, FL 33620
| | - Xiaoyong Lei
- Department of Cell, Developmental, and Integrative Biology University of Alabama at Birmingham, Birmingham, AL 35294.,Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Abdulaziz Almutairi
- Department of Cell, Developmental, and Integrative Biology University of Alabama at Birmingham, Birmingham, AL 35294.,Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Tayleur D White
- Department of Cell, Developmental, and Integrative Biology University of Alabama at Birmingham, Birmingham, AL 35294.,Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Ying G Tusing
- Department of Cell, Developmental, and Integrative Biology University of Alabama at Birmingham, Birmingham, AL 35294.,Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Margaret A Park
- Department of Cell Biology, Microbiology, and Molecular Biology (CMMB), University of South Florida, Tampa, FL 33620
| | - Suzanne E Barbour
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602
| | - Charles E Chalfant
- Department of Cell Biology, Microbiology, and Molecular Biology (CMMB), University of South Florida, Tampa, FL 33620.,Research Service, James A. Haley Veterans Hospital, Tampa, FL 33612
| | - Sasanka Ramanadham
- Department of Cell, Developmental, and Integrative Biology University of Alabama at Birmingham, Birmingham, AL 35294 .,Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
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12
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Szymczak-Pajor I, Kleniewska P, Wieczfinska J, Pawliczak R. Wide-Range Effects of 1,25(OH)2D3 on Group 4A Phospholipases Is Related to Nuclear Factor κ-B and Phospholipase-A2 Activating Protein Activity in Mast Cells. Int Arch Allergy Immunol 2019; 181:56-70. [PMID: 31707382 DOI: 10.1159/000503628] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 09/24/2019] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION Phospholipases are enzymes that occur in many types of human cells, including mast cells, and play an important role in the molecular background of asthma pathogenesis, and the development of inflammation NF-κB activities that affect numerous biological processes has been reported in many inflammatory diseases including asthma. Vitamin D is a widely studied factor that affects many diseases, including asthma. The aim of this study is to assess the influence of 1,25-(OH)2D3 on regulation of chosen phospholipase-A2 (PLA2) expression-selected inflammation mediators. METHODS LUVA mast cells were stimulated with 1,25(OH)2D3, and inhibitors of NF-κB p65 and ubiquitination. Expression analysis of phospholipases (PLA2G5, PLA2G10, PLA2G12, PLA2G15, PLA2G4A, PLA2G4B, PLA2G4C, PLAA, NF-κB p65, and UBC) was done utilizing real-time PCR and Western blot. Eicosanoid (LTC4, LXA4, 15[S]-HETE, and PGE2) levels and sPLA2 were also measured. RESULTS We found that 1,25(OH)2D3 decreased the expression of PLA2G5, PLA2G15, PLA2G5,UBC, and NF-κB p65 but increased expression of PLAA and PLA2G4C (p < 0.05). Moreover, the expression of PLA2G5 and PLA2G15 decreased after inhibition of NF-κB p65 and UBC. Increased levels of released LXA4 and 15(S)-HETE, decreased levels of LTC4, and sPLA2s enzymatic activity in response to 1,25(OH)2D3 were also observed. Additionally, NF-κB p65 inhibition led to an increase in the LXA4 concentration. CONCLUSION Future investigations will be needed to further clarify the role of 1,25(OH)2D3 in the context of asthma and the inflammatory process; however, these results confirm a variety of effects which can be caused by this vitamin. 1,25(OH)2D3-mediated action may result in the development of new therapeutic strategies for asthma treatment.
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Affiliation(s)
- Izabela Szymczak-Pajor
- Department of Immunopathology, Faculty of Biomedical Science and Postgraduate Training, Medical University of Lodz, Lodz, Poland
| | - Paulina Kleniewska
- Department of Immunopathology, Faculty of Biomedical Science and Postgraduate Training, Medical University of Lodz, Lodz, Poland
| | - Joanna Wieczfinska
- Department of Immunopathology, Faculty of Biomedical Science and Postgraduate Training, Medical University of Lodz, Lodz, Poland
| | - Rafal Pawliczak
- Department of Immunopathology, Faculty of Biomedical Science and Postgraduate Training, Medical University of Lodz, Lodz, Poland,
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Effect of Rhus verniciflua Extract on IgE-Antigen-Mediated Allergic Reaction in Rat Basophilic Leukemic RBL-2H3 Mast Cells and Passive Cutaneous Anaphylaxis in Mice. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2019; 2019:6497691. [PMID: 31687037 PMCID: PMC6811800 DOI: 10.1155/2019/6497691] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 08/03/2019] [Accepted: 08/26/2019] [Indexed: 01/10/2023]
Abstract
Rhus verniciflua is widely known for its antioxidant, antibacterial, anticancer, and antiaging efficacy and α-glucosidase inhibition. This study was designed whether Rhus verniciflua extracts inhibit the IgE-antigen-mediated allergic reaction in RBL-2H3 mast cells, and it further investigated the FcεRI- and arachidonate-signaling by which Rhus verniciflua extracts exert its antiallergic effects. IgE-antigen-sensitized RBL-2H3 mast cells were investigated for the cytotoxicity of Rhus verniciflua extracts and β-hexosaminidase release, and inflammatory mediators (e.g., TNF-α, IL-4, IL-6, histamine, and PGD2) were then assessed. Additionally, we examined expressions of genes involved in arachidonate- and FcεRI-signaling pathway in RBL-2H3. Rhus verniciflua extracts inhibited β-hexosaminidase release and production of the inflammatory mediators in RBL-2H3. Rhus verniciflua extracts reduced amounts of histamine and expressions of FcεRI signaling-related genes such as Lyn and Syk and phosphorylation of extracellular signal-regulated kinase in mast cells. Finally, in late allergic responses, Rhus verniciflua extracts reduced PGD2 release and COX-2 and cPLA2 phosphorylation expressions from IgE-antigen-mediated mast cells. Lastly, 250–500 mg/kg RVE significantly attenuated the Ag/IgE-induced passive cutaneous anaphylaxis (PCA) reaction in mice. These findings provide novel information on the molecular mechanisms underlying the antiallergy properties of Rhus verniciflua extracts in FcɛRI-mediated allergic reaction.
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Stanley D, Kim Y. Prostaglandins and Other Eicosanoids in Insects: Biosynthesis and Biological Actions. Front Physiol 2019; 9:1927. [PMID: 30792667 PMCID: PMC6375067 DOI: 10.3389/fphys.2018.01927] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 12/21/2018] [Indexed: 12/24/2022] Open
Abstract
This essay reviews the discoveries, synthesis, and biological significance of prostaglandins (PGs) and other eicosanoids in insect biology. It presents the most current - and growing - understanding of the insect mechanism of PG biosynthesis, provides an updated treatment of known insect phospholipase A2 (PLA2), and details contemporary findings on the biological roles of PGs and other eicosanoids in insect physiology, including reproduction, fluid secretion, hormone actions in fat body, immunity and eicosanoid signaling and cross-talk in immunity. It completes the essay with a prospectus meant to illuminate research opportunities for interested readers. In more detail, cellular and secretory types of PLA2, similar to those known on the biomedical background, have been identified in insects and their roles in eicosanoid biosynthesis documented. It highlights recent findings showing that eicosanoid biosynthetic pathway in insects is not identical to the solidly established biomedical picture. The relatively low concentrations of arachidonic acid (AA) present in insect phospholipids (PLs) (< 0.1% in some species) indicate that PLA2 may hydrolyze linoleic acid (LA) as a precursor of eicosanoid biosynthesis. The free LA is desaturated and elongated into AA. Unlike vertebrates, AA is not oxidized by cyclooxygenase, but by a specific peroxidase called peroxinectin to produce PGH2, which is then isomerized into cell-specific PGs. In particular, PGE2 synthase recently identified converts PGH2 into PGE2. In the cross-talks with other immune mediators, eicosanoids act as downstream signals because any inhibition of eicosanoid signaling leads to significant immunosuppression. Because host immunosuppression favors pathogens and parasitoids, some entomopathogens evolved a PLA2 inhibitory strategy activity to express their virulence.
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Affiliation(s)
- David Stanley
- Biological Control of Insects Research Laboratory, United States Department of Agriculture – Agricultural Research Service, Columbia, MO, United States
| | - Yonggyun Kim
- Department of Plant Medicals, Andong National University, Andong, South Korea
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15
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Sartim MA, Menaldo DL, Sampaio SV. Immunotherapeutic potential of Crotoxin: anti-inflammatory and immunosuppressive properties. J Venom Anim Toxins Incl Trop Dis 2018; 24:39. [PMID: 30564276 PMCID: PMC6296157 DOI: 10.1186/s40409-018-0178-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 12/04/2018] [Indexed: 12/15/2022] Open
Abstract
For the past 80 years, Crotoxin has become one of the most investigated isolated toxins from snake venoms, partially due to its major role as the main toxic component in the venom of the South American rattlesnake Crotalus durissus terrificus. However, in the past decades, progressive studies have led researchers to shift their focus on Crotoxin, opening novel perspectives and applications as a therapeutic approach. Although this toxin acts on a wide variety of biological events, the modulation of immune responses is considered as one of its most relevant behaviors. Therefore, the present review describes the scientific investigations on the capacity of Crotoxin to modulate anti-inflammatory and immunosuppressive responses, and its application as a medicinal immunopharmacological approach. In addition, this review will also discuss its mechanisms, involving cellular and molecular pathways, capable of improving pathological alterations related to immune-associated disorders.
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Affiliation(s)
- Marco Aurélio Sartim
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto-SP, 14040-903 Brazil
| | - Danilo Luccas Menaldo
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto-SP, 14040-903 Brazil
| | - Suely Vilela Sampaio
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto-SP, 14040-903 Brazil
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16
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Nolin JD, Murphy RC, Gelb MH, Altemeier WA, Henderson WR, Hallstrand TS. Function of secreted phospholipase A 2 group-X in asthma and allergic disease. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:827-837. [PMID: 30529275 DOI: 10.1016/j.bbalip.2018.11.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 11/28/2018] [Accepted: 11/30/2018] [Indexed: 12/11/2022]
Abstract
Elevated secreted phospholipase A2 (sPLA2) activity in the airways has been implicated in the pathogenesis of asthma and allergic disease for some time. The identity and function of these enzymes in asthma is becoming clear from work in our lab and others. We focused on sPLA2 group X (sPLA2-X) after identifying increased levels of this enzyme in asthma, and that it is responsible for a large portion of sPLA2 activity in the airways and that the levels are strongly associated with features of airway hyperresponsiveness (AHR). In this review, we discuss studies that implicated sPLA2-X in human asthma, and murine models that demonstrate a critical role of this enzyme as a regulator of type-2 inflammation, AHR and production of eicosanoids. We discuss the mechanism by which sPLA2-X acts to regulate eicosanoids in leukocytes, as well as effects that are mediated through the generation of lysophospholipids and through receptor-mediated functions. This article is part of a Special Issue entitled Novel functions of phospholipase A2 Guest Editors: Makoto Murakami and Gerard Lambeau.
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Affiliation(s)
- James D Nolin
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep, University of Washington, Seattle, WA, United States of America
| | - Ryan C Murphy
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep, University of Washington, Seattle, WA, United States of America
| | - Michael H Gelb
- Department of Chemistry, University of Washington, Seattle, WA, United States of America; Department of Biochemistry, University of Washington, Seattle, WA, United States of America
| | - William A Altemeier
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep, University of Washington, Seattle, WA, United States of America
| | - William R Henderson
- Division of Allergy and Infectious DIseases, University of Washington, Seattle, WA, United States of America
| | - Teal S Hallstrand
- Department of Medicine, Division of Pulmonary, Critical Care and Sleep, University of Washington, Seattle, WA, United States of America.
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Yagnik D, Hills F. Urate crystals induce macrophage PAF‑AH secretion which is differentially regulated by TGFβ1 and hydrocortisone. Mol Med Rep 2018; 18:3506-3512. [DOI: 10.3892/mmr.2018.9323] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 06/13/2018] [Indexed: 11/06/2022] Open
Affiliation(s)
- Darshna Yagnik
- Department of Natural Sciences, Biomarker Research Group, School of Science and Technology, Middlesex University, The Burroughs, London NW4 4BT, UK
| | - Frank Hills
- Department of Natural Sciences, Biomarker Research Group, School of Science and Technology, Middlesex University, The Burroughs, London NW4 4BT, UK
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18
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Hui DY. Group 1B phospholipase A 2 in metabolic and inflammatory disease modulation. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1864:784-788. [PMID: 30003964 DOI: 10.1016/j.bbalip.2018.07.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 07/02/2018] [Accepted: 07/05/2018] [Indexed: 12/11/2022]
Abstract
The group 1B phospholipase A2 (PLA2G1B) is a secreted phospholipase that catalyzes the hydrolytic removal of the sn-2 fatty acyl moiety from phospholipids. This enzyme is synthesized most abundantly in the pancreas and is also expressed in the lung. The first part of this review article focuses on the role of pancreatic-derived PLA2G1B in mediating lipid absorption and discusses how the PLA2G1B-derived metabolic product contributes to cardiometabolic diseases, including obesity, hyperinsulinemia, hyperlipidemia, and atherosclerosis. The anti-helminth properties of PLA2G1B will also be discussed. The second part of this review will focus on PLA2G1B expressed in the lung, and in vitro data suggest that how this enzyme may modulate lung inflammation via both hydrolytic activity-dependent and -dependent mechanisms. Finally, recent studies revealing a relationship between PLA2G1B and cancer will also be discussed. This article is part of a Special Issue entitled Novel functions of phospholipase A2 Guest Editors: Makoto Murakami and Gerard Lambeau.
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Affiliation(s)
- David Y Hui
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, Cincinnati, OH 45237, USA; Department of Pathology, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, 2120 E. Galbraith Road, Cincinnati, OH 45237, United States.
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19
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Nguyen TL, Perlman CE. Tracheal acid or surfactant instillation raises alveolar surface tension. J Appl Physiol (1985) 2018; 125:1357-1367. [PMID: 29771610 DOI: 10.1152/japplphysiol.00397.2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Whether alveolar liquid surface tension, T, is elevated in the acute respiratory distress syndrome (ARDS) has not been demonstrated in situ in the lungs. Neither is it known how exogenous surfactant, which has failed to treat ARDS, affects in situ T. We aim to determine T in an acid-aspiration ARDS model before and after exogenous surfactant administration. In isolated rat lungs, we combine servo-nulling pressure measurement and confocal microscopy to determine alveolar liquid T according to the Laplace relation. Administering 0.01 N (pH 1.9) HCl solution by alveolar injection or tracheal instillation, to model gastric liquid aspiration, raises T. Subsequent surfactant administration fails to normalize T. Furthermore, in normal lungs, tracheal instillation of control saline or exogenous surfactant raises T. Lavaging the trachea with saline and injecting the lavage solution into the alveolus raises T, suggesting that tracheal instillation may wash T-raising airway contents to the alveolus. Adding 0.01 N HCl or 5 mM CaCl2-either of which aggregates mucins-to tracheal lavage solution reduces or eliminates the effect of lavage solution on alveolar T. Following tracheal saline instillation, liquid suctioned directly out of alveoli through a micropipette contains mucins. Additionally, alveolar injection of gastric mucin solution raises T. We conclude that 1) tracheal liquid instillation likely washes T-raising mucins to the alveolus and 2) even exogenous surfactant that could be delivered mucin-free to the alveolus might not normalize T in acid-aspiration ARDS. NEW & NOTEWORTHY We demonstrate in situ in isolated lungs that surface tension is elevated in an acid-aspiration acute respiratory distress syndrome (ARDS) model. Following tracheal liquid instillation, also in isolated lungs, we directly sample alveolar liquid. We find that liquid instillation into normal lungs washes mucins to the alveolus, thereby raising alveolar surface tension. Furthermore, even if exogenous surfactant could be delivered mucin-free to the alveolus, exogenous surfactant might fail to normalize alveolar surface tension in acid-aspiration ARDS.
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Affiliation(s)
- Tam L Nguyen
- Department of Biomedical Engineering, Stevens Institute of Technology , Hoboken, New Jersey
| | - Carrie E Perlman
- Department of Biomedical Engineering, Stevens Institute of Technology , Hoboken, New Jersey
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Cytosolic Phospholipase A 2α Promotes Pulmonary Inflammation and Systemic Disease during Streptococcus pneumoniae Infection. Infect Immun 2017; 85:IAI.00280-17. [PMID: 28808157 DOI: 10.1128/iai.00280-17] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 08/02/2017] [Indexed: 02/07/2023] Open
Abstract
Pulmonary infection by Streptococcus pneumoniae is characterized by a robust alveolar infiltration of neutrophils (polymorphonuclear cells [PMNs]) that can promote systemic spread of the infection if not resolved. We previously showed that 12-lipoxygenase (12-LOX), which is required to generate the PMN chemoattractant hepoxilin A3 (HXA3) from arachidonic acid (AA), promotes acute pulmonary inflammation and systemic infection after lung challenge with S. pneumoniae As phospholipase A2 (PLA2) promotes the release of AA, we investigated the role of PLA2 in local and systemic disease during S. pneumoniae infection. The group IVA cytosolic isoform of PLA2 (cPLA2α) was activated upon S. pneumoniae infection of cultured lung epithelial cells and was critical for AA release from membrane phospholipids. Pharmacological inhibition of this enzyme blocked S. pneumoniae-induced PMN transepithelial migration in vitro Genetic ablation of the cPLA2 isoform cPLA2α dramatically reduced lung inflammation in mice upon high-dose pulmonary challenge with S. pneumoniae The cPLA2α-deficient mice also suffered no bacteremia and survived a pulmonary challenge that was lethal to wild-type mice. Our data suggest that cPLA2α plays a crucial role in eliciting pulmonary inflammation during pneumococcal infection and is required for lethal systemic infection following S. pneumoniae lung challenge.
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21
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Hou H, Xu Z, Zhang H, Xu Y. Combination diagnosis of multi-slice spiral computed tomography and secretary phospholipase A2-IIa for solitary pulmonary nodules. J Clin Lab Anal 2017; 32. [PMID: 28493533 DOI: 10.1002/jcla.22250] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Accepted: 04/05/2017] [Indexed: 12/19/2022] Open
Abstract
INTRODUCTION This study was aimed to compare the diagnostic value of multi-slice spiral computed tomography (CT) and secretary phospholipase A2-IIa (sPLA2-IIa) in differentiating between malignant and benign solitary pulmonary nodules (SPNs). METHODS A total of 223 patients with SPNs (91 patients with malignant SPNs and 132 patients with benign SPNs) were included from Weihai Central Hospital during October 2014 to December 2016. SPN diagnosis was confirmed in all patients using needle biopsy, surgery and bronchoscopy. The patients were managed with dynamic multi-slice CT scans, and their sPLA2-IIa levels were also detected. By selecting the area of interest of focus, the perfusion parameters of multi-slice CT targeting the focus were obtained. RESULTS The levels of MTT, PS, BV, BF and sPLA2-IIa significantly increased with increasing severity of SPNs (P<.05). Notably, BV (area under the ROC curve [AUC]=0.915; 95%CI: 0.88-0.95; sensitivity=91.21%; specificity=78.79%) showed a higher potential to discriminate patients with malignant SPNs from those with benign SPNs than did BF (AUC=0.712; 95%CI: 0.65-0.78; sensitivity=72.50%; specificity=59.10%), PS (AUC=0.772; 95%CI: 0.71-0.84; sensitivity=65.93%; specificity=82.58%) and MTT (AUC=0.600; 95%CI: 0.52-0.68; sensitivity=52.75%; specificity=78.03%). Finally, the combined diagnostic value of BV and sPLA2-IIa was quite ideal (AUC=0.947; 95%CI: 0.92-0.97; sensitivity=85.70%; specificity=92.70%) for malignant and benign SPNs. CONCLUSIONS The combined diagnostic value of BV and sPLA2-IIa appeared as a desirable detection method for malignant and benign SPNs.
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Affiliation(s)
- Hongjun Hou
- Department of Radiology, Weihai Central Hospital, Weihai City, Shandong Province, China
| | - Zushan Xu
- Department of Radiology, Weihai Central Hospital, Weihai City, Shandong Province, China
| | - Hongsheng Zhang
- Department of Radiology, Weihai Central Hospital, Weihai City, Shandong Province, China
| | - Yan Xu
- Department of Radiology, Capital Medical University Affiliated Beijing Friendship Hospital, Beijing, China
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22
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Lu S, Dong Z. Overexpression of secretory phospholipase A2-IIa supports cancer stem cell phenotype via HER/ERBB-elicited signaling in lung and prostate cancer cells. Int J Oncol 2017; 50:2113-2122. [PMID: 28440478 DOI: 10.3892/ijo.2017.3964] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 04/10/2017] [Indexed: 11/06/2022] Open
Abstract
Resistance to conventional chemotherapies remains a significant clinical challenge in treatment of cancer. The cancer stem cells (CSCs) have properties necessary for tumor initiation, resistance to therapy, and progression. HER/ERBB‑elicited signaling supports CSC properties. Our previous studies revealed that secretory phospholipase A2 group IIa (sPLA2‑IIa) is overexpressed in both prostate and lung cancer cells, leading to an aberrant high level in the interstitial fluid, i.e., tumor microenvironment and blood. HER/ERBB-PI3K-Akt-NF-κB signaling stimulates sPLA2‑IIa overexpression, and in turn, sPLA2‑IIa activates EGFR family receptors and HER/ERBB-elicited signaling and stimulates sPLA2‑IIa overexpression in a positive feedback manner. The present study determined the molecular mechanisms of sPLA2‑IIa in stimulating HER/ERBB-elicited signaling and supporting CSC properties. We found that sPLA2‑IIa binds both EGFR and HER3 demonstrated by co-immunoprecipitation experiments and also indirectly interacts with HER2, suggesting that sPLA2‑IIa functions as a ligand for both EGFR and HER3. Furthermore, both side population CSCs from non-small cell lung cancer (NSCLC) A549 and H1975 cells and ALDH1‑high CSCs from castration-resistant prostate cancer (CRPC) 22Rv1 cells overexpress sPLA2‑IIa and produce tumors when inoculated into subcutis of nude mice. Given an aberrant high level of sPLA2‑IIa in the tumor microenvironment that should be much higher than that in the blood, our findings support the notion that sPLA2‑IIa functions as a ligand for EGFR family receptors and supports CSC properties via HER/ERBB-elicited signaling, which may contribute to resistance to therapy and cancer progression.
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Affiliation(s)
- Shan Lu
- Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Zhongyun Dong
- Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
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Cardamone C, Parente R, Feo GD, Triggiani M. Mast cells as effector cells of innate immunity and regulators of adaptive immunity. Immunol Lett 2016; 178:10-4. [PMID: 27393494 DOI: 10.1016/j.imlet.2016.07.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 07/04/2016] [Indexed: 02/06/2023]
Abstract
Mast cells are widely distributed in human organs and tissues and they are particularly abundant at major body interfaces with the external environment such as the skin, the lung and the gastrointestinal tract. Moreover, mast cells are located around blood vessels and are highly represented within central and peripheral lymphoid organs. The strategic distribution of mast cells closely reflects the primary role of these cells in providing first-line defense against environmental dangers, in regulating local and systemic inflammatory reactions and in shaping innate and adaptive immune responses. Human mast cells have pleiotropic and multivalent functions that make them highly versatile cells able to rapidly adapt responses to microenvironmental changes. They express a wide variety of surface receptors including immunoglobulin receptors, pathogen-associated molecular pattern receptors and danger signal receptors. The abundance of these receptors makes mast cells unique and effective surveillance cells able to detect promptly aggression by viral, bacterial and parasitic agents. In addition, mast cells express multiple receptors for cytokines and chemokines that confer them the capacity of being recruited and activated at sites of inflammation. Once activated by immunological or nonimmunological stimuli mast cells secrete a wide spectrum of preformed (early) and de novo synthesized (late) mediators. Preformed mediators are stored within granules and are rapidly released in the extracellular environment to provide a fast vascular response that promotes inflammation and local recruitment of other innate immunity cells such as neutrophils, eosinophils, basophils and monocyte/macrophages. Later on, delayed release of multiple cytokines and chemokines from mast cells further induce modulation of cells of adaptive immunity and regulates tissue injury and, eventually, resolution of inflammation. Finally, mast cells express several costimulatory and inhibitory surface molecules that can finely tune activities of T cells, B cells and regulatory cells by cognate interactions within lymphoid organs. The multivalent capacity to recognize and to react to internal and external dangers together with their ability to cross-talk with other immunocompetent cells make mast cells a unique effector cell of innate responses and a main bridge between innate and adaptive immunity.
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Affiliation(s)
- Chiara Cardamone
- Division of Allergy and Clinical Immunology, University of Salerno, Italy
| | - Roberta Parente
- Division of Allergy and Clinical Immunology, University of Salerno, Italy
| | - Giulia De Feo
- Division of Allergy and Clinical Immunology, University of Salerno, Italy
| | - Massimo Triggiani
- Division of Allergy and Clinical Immunology, University of Salerno, Italy.
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Exogenous Glutamine in Respiratory Diseases: Myth or Reality? Nutrients 2016; 8:76. [PMID: 26861387 PMCID: PMC4772040 DOI: 10.3390/nu8020076] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 01/20/2016] [Accepted: 01/26/2016] [Indexed: 01/09/2023] Open
Abstract
Several respiratory diseases feature increased inflammatory response and catabolic activity, which are associated with glutamine depletion; thus, the benefits of exogenous glutamine administration have been evaluated in clinical trials and models of different respiratory diseases. Recent reviews and meta-analyses have focused on the effects and mechanisms of action of glutamine in a general population of critical care patients or in different models of injury. However, little information is available about the role of glutamine in respiratory diseases. The aim of the present review is to discuss the evidence of glutamine depletion in cystic fibrosis (CF), asthma, chronic obstructive pulmonary disease (COPD), acute respiratory distress syndrome (ARDS), and lung cancer, as well as the results of exogenous glutamine administration in experimental and clinical studies. Exogenous glutamine administration might be beneficial in ARDS, asthma, and during lung cancer treatment, thus representing a potential therapeutic tool in these conditions. Further experimental and large randomized clinical trials focusing on the development and progression of respiratory diseases are necessary to elucidate the effects and possible therapeutic role of glutamine in this setting.
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Wang YH, Nemati R, Anstadt E, Liu Y, Son Y, Zhu Q, Yao X, Clark RB, Rowe DW, Nichols FC. Serine dipeptide lipids of Porphyromonas gingivalis inhibit osteoblast differentiation: Relationship to Toll-like receptor 2. Bone 2015; 81:654-661. [PMID: 26409254 PMCID: PMC4641032 DOI: 10.1016/j.bone.2015.09.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 09/15/2015] [Accepted: 09/19/2015] [Indexed: 11/16/2022]
Abstract
Porphyromonas gingivalis is a periodontal pathogen strongly associated with loss of attachment and supporting bone for teeth. We have previously shown that the total lipid extract of P. gingivalis inhibits osteoblast differentiation through engagement of Toll-like receptor 2 (TLR2) and that serine dipeptide lipids of P. gingivalis engage both mouse and human TLR2. The purpose of the present investigation was to determine whether these serine lipids inhibit osteoblast differentiation in vitro and in vivo and whether TLR2 engagement is involved. Osteoblasts were obtained from calvaria of wild type or TLR2 knockout mouse pups that also express the Col2.3GFP transgene. Two classes of serine dipeptide lipids, termed Lipid 654 and Lipid 430, were tested. Osteoblast differentiation was monitored by cell GFP fluorescence and osteoblast gene expression and osteoblast function was monitored as von Kossa stained mineral deposits. Osteoblast differentiation and function were evaluated in calvarial cell cultures maintained for 21 days. Lipid 654 significantly inhibited GFP expression, osteoblast gene expression and mineral nodule formation and this inhibition was dependent on TLR2 engagement. Lipid 430 also significantly inhibited GFP expression, osteoblast gene expression and mineral nodule formation but these effects were only partially attributed to engagement of TLR2. More importantly, Lipid 430 stimulated TNF-α and RANKL gene expression in wild type cells but not in TLR2 knockout cells. Finally, osteoblast cultures were observed to hydrolyze Lipid 654 to Lipid 430 and this likely occurs through elevated PLA2 activity in the cultured cells. In conclusion, our results show that serine dipeptide lipids of P. gingivalis inhibit osteoblast differentiation and function at least in part through engagement of TLR2. The Lipid 430 serine class also increased the expression of genes that could increase osteoclast activity. We conclude that Lipid 654 and Lipid 430 have the potential to promote TLR2-dependent bone loss as is reported in experimental periodontitis following oral infection with P. gingivalis. These results also support the conclusion that serine dipeptide lipids are involved in alveolar bone loss in chronic periodontitis.
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Affiliation(s)
- Yu-Hsiung Wang
- Department of Craniofacial Sciences, University of Connecticut School of Dental Medicine, Farmington, CT 06030, USA
| | - Reza Nemati
- From the Department of Chemistry, University of Connecticut, Storrs, CT 06269-3060, USA
| | - Emily Anstadt
- Department of Immunology and Medicine, University of Connecticut School of Medicine, Farmington, CT 06030, USA
| | - Yaling Liu
- Department of Oral Health and Diagnostic Sciences, University of Connecticut School of Dental Medicine, Farmington, CT 06030, USA
| | - Young Son
- Department of Oral Health and Diagnostic Sciences, University of Connecticut School of Dental Medicine, Farmington, CT 06030, USA
| | - Qiang Zhu
- Department of Oral Health and Diagnostic Sciences, University of Connecticut School of Dental Medicine, Farmington, CT 06030, USA
| | - Xudong Yao
- From the Department of Chemistry, University of Connecticut, Storrs, CT 06269-3060, USA; Institute for Systems Genomics, University of Connecticut, Storrs, CT 06269, USA
| | - Robert B Clark
- Department of Immunology and Medicine, University of Connecticut School of Medicine, Farmington, CT 06030, USA
| | - David W Rowe
- Department of Reconstuctive Sciences, University of Connecticut School of Dental Medicine, Farmington, CT 06030, USA
| | - Frank C Nichols
- Department of Oral Health and Diagnostic Sciences, University of Connecticut School of Dental Medicine, Farmington, CT 06030, USA.
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Mruwat R, Kivity S, Landsberg R, Yedgar S, Langier S. Phospholipase A2-dependent Release of Inflammatory Cytokines by Superantigen-Stimulated Nasal Polyps of Patients with Chronic Rhinosinusitis. Am J Rhinol Allergy 2015; 29:e122-8. [DOI: 10.2500/ajra.2015.29.4224] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Background Chronic rhinosinusitis (CRS) is an inflammatory/allergic disease with unclear pathophysiology, but it has been linked to an imbalance in the production of eicosanoids, which are metabolites of arachidonic acid, and results from phospholipids hydrolysis by phospholipase A2 (PLA2). As of yet, the role of PLA2 in CRS has hardly been studied, except for a report that group II PLA2 expression is elevated in interleukin (IL) 1β or tumor necrosis factor α-stimulated CRS nasal tissues with and without polyps. The PLA2 families include extracellular (secretory) and intracellular isoforms, which are involved in the regulation of inflammatory processes in different ways. Here we comprehensively investigated the expression of PLA2s, particularly those reported to be involved in respiratory disorders, in superantigen (SAE)-stimulated nasal polyps from patients with CRS with polyps, and determined their role in inflammatory cytokine production by inhibition of PLA2 expression. Methods The release of IL-5, IL-13, IL-17, and interferon γ by nasal polyps dispersed cells (NPDC) was determined concomitantly with PLA2 messenger RNA expression, under SAE stimulation, with or without dexamethasone, as a regulator of PLA2 expression. Results Stimulation of NPDCs by SAE-induced cytokine secretion with enhanced expression of several secretory PLA2 and Ca2+-independent PLA2, while suppressing cytosolic PLA2 expression. All these were reverted to the level of unstimulated NPDCs on treatment with dexamethasone. Conclusion This study further supports the key role of secretory PLA2 in the pathophysiology of respiratory disorders and presents secretory PLA2 inhibition as a therapeutic strategy for the treatment of CRS and airway pathologies in general.
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Affiliation(s)
- Rufayda Mruwat
- Department of Biochemistry, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | | | - Roee Landsberg
- Ear Nose and Throat Department, Tel Aviv Medical Center, Sackler School of Medicine, Tel Aviv University, Tel Aviv, lsrael
| | - Saul Yedgar
- Department of Biochemistry, Hebrew University-Hadassah Medical School, Jerusalem, Israel
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Tanabe T, Shimokawaji T, Kanoh S, Rubin BK. Secretory phospholipases A2 are secreted from ciliated cells and increase mucin and eicosanoid secretion from goblet cells. Chest 2015; 147:1599-1609. [PMID: 25429648 DOI: 10.1378/chest.14-0258] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Secretory phospholipases A2 (sPLA2) initiate the biosynthesis of eicosanoids, are increased in the airways of people with severe asthma, and induce mucin hypersecretion. We used IL-13-transformed, highly enriched goblet cells and differentiated (ciliary cell-enriched) human bronchial epithelial cell culture to evaluate the relative contribution of ciliated and goblet cells to airway sPLA2 generation and response. We wished to determine the primary source(s) of sPLA2 and leukotrienes in human airway epithelial cells. METHODS Human bronchial epithelial cells from subjects without lung disease were differentiated to a ciliated-enriched or goblet-enriched cell phenotype. Synthesis of sPLA2, cysteinyl leukotrienes (cysLTs), and airway mucin messenger RNA and protein was measured by real-time-polymerase chain reaction and an enzyme-linked immunosorbent assay, and the localization of mucin and sPLA2 to specific cells types was confirmed by confocal microscopy. RESULTS sPLA2 group IIa, V, and X messenger RNA expression was increased in ciliated-enriched cells (P < .001) but not in goblet-enriched cells. sPLA2 were secreted from the apical (air) side of ciliated-enriched cells but not goblet-enriched cells (P < .001). Immunostaining of sPLA2 V was strongly positive in ciliated-enriched cells but not in goblet-enriched cells. sPLA2 released cysLTs from goblet-enriched cells but not from ciliated-enriched cells, and this result was greatest with sPLA2 V (P < .05). sPLA2 V increased goblet-enriched cell mucin secretion, which was inhibited by inhibitors of lipoxygenase or cyclooxygenase (P < .02). CONCLUSIONS sPLA2 are secreted from ciliated cells and appear to induce mucin and cysLT secretion from goblet cells, strongly suggesting that airway goblet cells are proinflammatory effector cells.
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Affiliation(s)
- Tsuyoshi Tanabe
- Department of Pediatrics, Virginia Commonwealth University School of Medicine, Richmond, VA.
| | - Tadasuke Shimokawaji
- Department of Pediatrics, Virginia Commonwealth University School of Medicine, Richmond, VA
| | - Soichiro Kanoh
- Department of Pediatrics, Virginia Commonwealth University School of Medicine, Richmond, VA
| | - Bruce K Rubin
- Department of Pediatrics, Virginia Commonwealth University School of Medicine, Richmond, VA
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In vitro anti-Plasmodium falciparum properties of the full set of human secreted phospholipases A2. Infect Immun 2015; 83:2453-65. [PMID: 25824843 DOI: 10.1128/iai.02474-14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 03/25/2015] [Indexed: 01/23/2023] Open
Abstract
We have previously shown that secreted phospholipases A2 (sPLA2s) from animal venoms inhibit the in vitro development of Plasmodium falciparum, the agent of malaria. In addition, the inflammatory-type human group IIA (hGIIA) sPLA2 circulates at high levels in the serum of malaria patients. However, the role of the different human sPLA2s in host defense against P. falciparum has not been investigated. We show here that 4 out of 10 human sPLA2s, namely, hGX, hGIIF, hGIII, and hGV, exhibit potent in vitro anti-Plasmodium properties with half-maximal inhibitory concentrations (IC50s) of 2.9 ± 2.4, 10.7 ± 2.1, 16.5 ± 9.7, and 94.2 ± 41.9 nM, respectively. Other human sPLA2s, including hGIIA, are inactive. The inhibition is dependent on sPLA2 catalytic activity and primarily due to hydrolysis of plasma lipoproteins from the parasite culture. Accordingly, purified lipoproteins that have been prehydrolyzed by hGX, hGIIF, hGIII, and hGV are more toxic to P. falciparum than native lipoproteins. However, the total enzymatic activities of human sPLA2s on purified lipoproteins or plasma did not reflect their inhibitory activities on P. falciparum. For instance, hGIIF is 9-fold more toxic than hGV but releases a lower quantity of nonesterified fatty acids (NEFAs). Lipidomic analyses of released NEFAs from lipoproteins demonstrate that sPLA2s with anti-Plasmodium properties are those that release polyunsaturated fatty acids (PUFAs), with hGIIF being the most selective enzyme. NEFAs purified from lipoproteins hydrolyzed by hGIIF were more potent at inhibiting P. falciparum than those from hGV, and PUFA-enriched liposomes hydrolyzed by sPLA2s were highly toxic, demonstrating the critical role of PUFAs. The selectivity of sPLA2s toward low- and high-density (LDL and HDL, respectively) lipoproteins and their ability to directly attack parasitized erythrocytes further explain their anti-Plasmodium activity. Together, our findings indicate that 4 human sPLA2s are active against P. falciparum in vitro and pave the way to future investigations on their in vivo contribution in malaria pathophysiology.
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Kitsiouli E, Antoniou G, Gotzou H, Karagiannopoulos M, Basagiannis D, Christoforidis S, Nakos G, Lekka ME. Effect of azithromycin on the LPS-induced production and secretion of phospholipase A2 in lung cells. Biochim Biophys Acta Mol Basis Dis 2015; 1852:1288-97. [PMID: 25791017 DOI: 10.1016/j.bbadis.2015.03.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 03/07/2015] [Accepted: 03/10/2015] [Indexed: 01/12/2023]
Abstract
Azithromycin is a member of macrolides, utilized in the treatment of infections. Independently, these antibiotics also possess anti-inflammatory and immunomodulatory properties. Phospholipase A2 isotypes, which are implicated in the pathophysiology of inflammatory lung disorders, are produced by alveolar macrophages and other lung cells during inflammatory response and can promote lung injury by destructing lung surfactant. The aim of the study was to investigate whether in lung cells azithromycin can inhibit secretory and cytosolic phospholipases A2, (sPLA2) and (cPLA2), respectively, which are induced by an inflammatory trigger. In this respect, we studied the lipopolysaccharide (LPS)-mediated production or secretion of sPLA2 and cPLA2 from A549 cells, a cancer bronchial epithelial cell line, and alveolar macrophages, isolated from bronchoalveolar lavage fluid of ARDS and control patients without cardiopulmonary disease or sepsis. Pre-treatment of cells with azithromycin caused a dose-dependent decrease in the LPS-induced sPLA2-IIA levels in A549 cells. This inhibition was rather due to reduced PLA2G2A mRNA expression and secretion of sPLA2-IIA protein levels, as observed by western blotting and indirect immunofluorescence by confocal microscopy, respectively, than to the inhibition of the enzymic activity per se. On the contrary, azithromycin had no effect on the LPS-induced production or secretion of sPLA2-IIA from alveolar macrophages. The levels of LPS-induced c-PLA2 were not significantly affected by azithromycin in either cell type. We conclude that azithromycin exerts anti-inflammatory properties on lung epithelial cells through the inhibition of both the expression and secretion of LPS-induced sPLA2-IIA, while it does not affect alveolar macrophages.
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Affiliation(s)
- Eirini Kitsiouli
- Laboratory of Biochemistry, Chemistry Department, School of Science, University of Ioannina, Greece
| | - Georgia Antoniou
- Laboratory of Biochemistry, Chemistry Department, School of Science, University of Ioannina, Greece
| | - Helen Gotzou
- Laboratory of Biochemistry, Chemistry Department, School of Science, University of Ioannina, Greece
| | | | - Dimitris Basagiannis
- Institute of Molecular Biology and Biotechnology, Biomedical Research, Foundation for Research and Technology, Ioannina, Greece; Laboratory of Biological Chemistry, Medical School, University of Ioannina, Greece
| | - Savvas Christoforidis
- Institute of Molecular Biology and Biotechnology, Biomedical Research, Foundation for Research and Technology, Ioannina, Greece; Laboratory of Biological Chemistry, Medical School, University of Ioannina, Greece
| | - George Nakos
- Department of Intensive Care Medicine, School of Medicine, University of Ioannina, Greece.
| | - Marilena E Lekka
- Laboratory of Biochemistry, Chemistry Department, School of Science, University of Ioannina, Greece.
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Brglez V, Lambeau G, Petan T. Secreted phospholipases A2 in cancer: Diverse mechanisms of action. Biochimie 2014; 107 Pt A:114-23. [DOI: 10.1016/j.biochi.2014.09.023] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2014] [Accepted: 09/25/2014] [Indexed: 12/24/2022]
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sPLA2 IB induces human podocyte apoptosis via the M-type phospholipase A2 receptor. Sci Rep 2014; 4:6660. [PMID: 25335547 PMCID: PMC4205892 DOI: 10.1038/srep06660] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 09/29/2014] [Indexed: 02/07/2023] Open
Abstract
The M-type phospholipase A2 receptor (PLA2R) is expressed in podocytes in human glomeruli. Group IB secretory phospholipase A2 (sPLA2 IB), which is one of the ligands of the PLA2R, is more highly expressed in chronic renal failure patients than in controls. However, the roles of the PLA2R and sPLA2 IB in the pathogenesis of glomerular diseases are unknown. In the present study, we found that more podocyte apoptosis occurs in the kidneys of patients with higher PLA2R and serum sPLA2 IB levels. In vitro, we demonstrated that human podocyte cells expressed the PLA2R in the cell membrane. After binding with the PLA2R, sPLA2 IB induced podocyte apoptosis in a time- and concentration-dependent manner. sPLA2 IB-induced podocyte PLA2R upregulation was not only associated with increased ERK1/2 and cPLA2α phosphorylation but also displayed enhanced apoptosis. In contrast, PLA2R-silenced human podocytes displayed attenuated apoptosis. sPLA2 IB enhanced podocyte arachidonic acid (AA) content in a dose-dependent manner. These data indicate that sPLA2 IB has the potential to induce human podocyte apoptosis via binding to the PLA2R. The sPLA2 IB-PLA2R interaction stimulated podocyte apoptosis through activating ERK1/2 and cPLA2α and through increasing the podocyte AA content.
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DONG ZHONGYUN, MELLER JAROSLAW, SUCCOP PAUL, WANG JIANG, WIKENHEISER-BROKAMP KATHRYN, STARNES SANDRA, LU SHAN. Secretory phospholipase A2-IIa upregulates HER/HER2-elicited signaling in lung cancer cells. Int J Oncol 2014; 45:978-84. [PMID: 24913497 PMCID: PMC4121404 DOI: 10.3892/ijo.2014.2486] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 02/03/2014] [Indexed: 11/06/2022] Open
Abstract
Lung cancer is the leading cause of cancer death worldwide. There is an urgent need for early diagnostic tools and novel therapies in order to increase lung cancer survival. Secretory phospholipase A2 group IIa (sPLA2-IIa) is involved in inflammation, tumorigenesis and metastasis. We were the first to uncover that cancer cells secrete sPLA2‑IIa. sPLA2‑IIa is overexpressed in almost all specimens of human lung cancers examined and is significantly elevated in the plasma of lung cancer patients. High levels of plasma sPLA2-IIa are significantly associated with advanced stage and decreased overall cancer survival. In this study, we further showed that elevated HER/HER2‑PI3K-Akt-NF-κB signaling contributes to sPLA2-IIa overexpression in lung cancer cells. sPLA2-IIa in turn phosphorylates and activates HER2 and HER3 in a time- and dose‑dependent manner in lung cancer cells. The structure and sequence‑based docking analysis revealed that sPLA2-IIa β hairpin shares structural similarity with the corresponding EGF hairpin. sPLA2-IIa forms an extensive interface with EGFR and brings the two lobes of EGFR into an active conformation. sPLA2-IIa also enhances the NF-κB promoter activity. Anti-sPLA2-IIa antibody, but not the small molecule sPLA2-IIa inhibitor LY315920, significantly inhibits sPLA2‑IIa-induced activation of NF-κB promoter. Our findings support the notion that sPLA2-IIa functions as a ligand for the EGFR family of receptors leading to an elevated HER/HER2-elicited signaling. Plasma sPLA2-IIa can potentially serve as lung cancer biomarker and sPLA2‑IIa is a potential therapeutic target against lung cancer.
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Affiliation(s)
- ZHONGYUN DONG
- Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45237, USA
| | - JAROSLAW MELLER
- Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, OH 45237, USA
| | - PAUL SUCCOP
- Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, OH 45237, USA
| | - JIANG WANG
- Department of Pathology, University of Cincinnati College of Medicine, Cincinnati, OH 45237, USA
| | | | - SANDRA STARNES
- Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, OH 45237, USA
| | - SHAN LU
- Department of Pathology, University of Cincinnati College of Medicine, Cincinnati, OH 45237, USA
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The step further to understand the role of cytosolic phospholipase A2 alpha and group X secretory phospholipase A2 in allergic inflammation: pilot study. BIOMED RESEARCH INTERNATIONAL 2014; 2014:670814. [PMID: 25247183 PMCID: PMC4163415 DOI: 10.1155/2014/670814] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 08/11/2014] [Accepted: 08/11/2014] [Indexed: 11/18/2022]
Abstract
Allergens, viral, and bacterial infections are responsible for asthma exacerbations that occur with progression of airway inflammation. cPLA2α and sPLA2X are responsible for delivery of arachidonic acid for production of eicosanoids—one of the key mediators of airway inflammation. However, cPLA2α and sPLA2X role in allergic inflammation has not been fully elucidated. The aim of this study was to analyze the influence of rDer p1 and rFel d1 and lipopolysaccharide (LPS) on cPLA2α expression and sPLA2X secretion in PBMC of asthmatics and in A549 cell line. PBMC isolated from 14 subjects, as well as A549 cells, were stimulated with rDer p1, rFel d1, and LPS. Immunoblotting technique was used to study the changes in cPLA2α protein expression and ELISA was used to analyze the release of sPLA2X. PBMC of asthmatics released more sPLA2X than those from healthy controls in the steady state. rDer p1 induced more sPLA2X secretion than cPLA2α protein expression. rFel d1 caused decrease in cPLA2α relative expression in PBMC of asthmatics and in A549 cells. Summarizing, Der p1 and Fel d1 involve phospholipase A2 enzymes in their action. sPLA2X seems to be one of important PLA2 isoform in allergic inflammation, especially caused by house dust mite allergens.
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Perelman B, Adil A, Vadas P. Relationship between platelet activating factor acetylhydrolase activity and apolipoprotein B levels in patients with peanut allergy. Allergy Asthma Clin Immunol 2014; 10:20. [PMID: 24808915 PMCID: PMC4012516 DOI: 10.1186/1710-1492-10-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Accepted: 03/31/2014] [Indexed: 11/10/2022] Open
Abstract
Background Platelet-activating factor (PAF) is a highly potent phospholipid mediator responsible for the life-threatening manifestations of anaphylaxis. PAF acetylhydrolase (PAF-AH) inactivates PAF and protects against severe anaphylaxis whereas deficiency of PAF-AH predisposes to severe or fatal anaphylaxis. Determinants of PAF-AH activity have not been studied in patients with peanut allergy. Objectives To determine whether plasma PAF-AH activity in patients with peanut allergy is related to formation of circulating complexes with apolipoprotein B (apoB) the main surface protein on low density lipoprotein particles. Methods Plasma PAF-AH activity and apoB concentrations were measured in 63 peanut allergic patients (35 boys, 28 girls, ages 2 – 19 years). ApoB concentration was measured immunoturbidimetrically using goat anti-human apoB. The correlation between PAF-AH activity and apoB concentration was determined. Results A positive correlation was found between PAF-AH activity and apoB concentration (r2 = 0.59, P < 0.0001). Conclusion In peanut allergic patients, PAF-AH activity strongly correlates with apoB concentration, suggesting the presence of circulating PAF-AH- lipoprotein complexes.
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Affiliation(s)
- Boris Perelman
- Division of Allergy and Clinical Immunology, Department of Medicine, St. Michael's Hospital, University of Toronto, 30 Bond St., M5B 1 W8 Toronto, ON, Canada
| | - Areej Adil
- Division of Allergy and Clinical Immunology, Department of Medicine, St. Michael's Hospital, University of Toronto, 30 Bond St., M5B 1 W8 Toronto, ON, Canada
| | - Peter Vadas
- Division of Allergy and Clinical Immunology, Department of Medicine, St. Michael's Hospital, University of Toronto, 30 Bond St., M5B 1 W8 Toronto, ON, Canada
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Critical role of TLR2 and MyD88 for functional response of macrophages to a group IIA-secreted phospholipase A2 from snake venom. PLoS One 2014; 9:e93741. [PMID: 24718259 PMCID: PMC3981733 DOI: 10.1371/journal.pone.0093741] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Accepted: 03/06/2014] [Indexed: 01/10/2023] Open
Abstract
The snake venom MT-III is a group IIA secreted phospholipase A2 (sPLA2) enzyme with functional and structural similarities with mammalian pro-inflammatory sPLA2s of the same group. Previously, we demonstrated that MT-III directly activates the innate inflammatory response of macrophages, including release of inflammatory mediators and formation of lipid droplets (LDs). However, the mechanisms coordinating these processes remain unclear. In the present study, by using TLR2−/− or MyD88−/− or C57BL/6 (WT) male mice, we report that TLR2 and MyD88 signaling have a critical role in MT-III-induced inflammatory response in macrophages. MT-III caused a marked release of PGE2, PGD2, PGJ2, IL-1β and IL-10 and increased the number of LDs in WT macrophages. In MT-III-stimulated TLR2−/− macrophages, formation of LDs and release of eicosanoids and cytokines were abrogated. In MyD88−/− macrophages, MT-III-induced release of PGE2, IL-1β and IL-10 was abrogated, but release of PGD2 and PGJ2 was maintained. In addition, COX-2 protein expression seen in MT-III-stimulated WT macrophages was abolished in both TLR2−/− and MyD88−/− cells, while perilipin 2 expression was abolished only in MyD88−/− cells. We further demonstrated a reduction of saturated, monounsaturated and polyunsaturated fatty acids and a release of the TLR2 agonists palmitic and oleic acid from MT-III-stimulated WT macrophages compared with WT control cells, thus suggesting these fatty acids as major messengers for MT-III-induced engagement of TLR2/MyD88 signaling. Collectively, our findings identify for the first time a TLR2 and MyD88-dependent mechanism that underlies group IIA sPLA2-induced inflammatory response in macrophages.
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Mruwat R, Yedgar S, Lavon I, Ariel A, Krimsky M, Shoseyov D. Phospholipase A2 in experimental allergic bronchitis: a lesson from mouse and rat models. PLoS One 2013; 8:e76641. [PMID: 24204651 PMCID: PMC3812210 DOI: 10.1371/journal.pone.0076641] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 08/21/2013] [Indexed: 11/26/2022] Open
Abstract
Background Phospholipases A2 (PLA2) hydrolyzes phospholipids, initiating the production of inflammatory lipid mediators. We have previously shown that in rats, sPLA2 and cPLA2 play opposing roles in the pathophysiology of ovalbumin (OVA)-induced experimental allergic bronchitis (OVA-EAB), an asthma model: Upon disease induction sPLA2 expression and production of the broncho-constricting CysLTs are elevated, whereas cPLA2 expression and the broncho-dilating PGE2 production are suppressed. These were reversed upon disease amelioration by treatment with an sPLA2 inhibitor. However, studies in mice reported the involvement of both sPLA2 and cPLA2 in EAB induction. Objectives To examine the relevance of mouse and rat models to understanding asthma pathophysiology. Methods OVA-EAB was induced in mice using the same methodology applied in rats. Disease and biochemical markers in mice were compared with those in rats. Results As in rats, EAB in mice was associated with increased mRNA of sPLA2, specifically sPLA2gX, in the lungs, and production of the broncho-constricting eicosanoids CysLTs, PGD2 and TBX2 in bronchoalveolar lavage (BAL). In contrast, EAB in mice was associated also with elevated cPLA2 mRNA and PGE2 production. Yet, treatment with an sPLA2 inhibitor ameliorated the EAB concomitantly with reverting the expression of both cPLA2 and sPLA2, and eicosanoid production. Conclusions In both mice and rats sPLA2 is pivotal in OVA-induced EAB. Yet, amelioration of asthma markers in mouse models, and human tissues, was observed also upon cPLA2 inhibition. It is plausible that airway conditions, involving multiple cell types and organs, require the combined action of more than one, essential, PLA2s.
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MESH Headings
- Animals
- Arachidonate 5-Lipoxygenase/immunology
- Arachidonate 5-Lipoxygenase/metabolism
- Arginase/genetics
- Arginase/immunology
- Arginase/metabolism
- Asthma/genetics
- Asthma/immunology
- Asthma/metabolism
- Blotting, Western
- Bronchitis/genetics
- Bronchitis/immunology
- Bronchitis/metabolism
- Bronchoalveolar Lavage Fluid/chemistry
- Bronchoalveolar Lavage Fluid/immunology
- Chitinases/genetics
- Chitinases/immunology
- Chitinases/metabolism
- Cysteine/immunology
- Cysteine/metabolism
- Dinoprostone/immunology
- Dinoprostone/metabolism
- Disease Models, Animal
- Female
- Group X Phospholipases A2/genetics
- Group X Phospholipases A2/immunology
- Group X Phospholipases A2/metabolism
- Humans
- Leukotrienes/immunology
- Leukotrienes/metabolism
- Lung/immunology
- Lung/metabolism
- Lung/pathology
- Mice
- Mice, Inbred BALB C
- Ovalbumin/immunology
- Phospholipases A2, Cytosolic/genetics
- Phospholipases A2, Cytosolic/immunology
- Phospholipases A2, Cytosolic/metabolism
- Phospholipases A2, Secretory/genetics
- Phospholipases A2, Secretory/immunology
- Phospholipases A2, Secretory/metabolism
- Prostaglandin D2/immunology
- Prostaglandin D2/metabolism
- Rats
- Receptors, Leukotriene/immunology
- Receptors, Leukotriene/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- T-Box Domain Proteins/immunology
- T-Box Domain Proteins/metabolism
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Affiliation(s)
- Rufayda Mruwat
- Department of Biochemistry, Hebrew University Medical School, Jerusalem, Israel
| | - Saul Yedgar
- Department of Biochemistry, Hebrew University Medical School, Jerusalem, Israel
- * E-mail:
| | - Iris Lavon
- Department of Neurology, Hadassah University Hospital, Jerusalem, Israel
| | - Amiram Ariel
- Department of Biology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
| | - Miron Krimsky
- Department of Neurology, Hadassah University Hospital, Jerusalem, Israel
- Pediatric Department, Hadassah University Hospital, Jerusalem, Israel
| | - David Shoseyov
- Pediatric Department, Hadassah University Hospital, Jerusalem, Israel
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Menschikowski M, Hagelgans A, Fuessel S, Mareninova OA, Asatryan L, Wirth MP, Siegert G. Serum amyloid A, phospholipase A2-IIA and C-reactive protein as inflammatory biomarkers for prostate diseases. Inflamm Res 2013; 62:1063-72. [DOI: 10.1007/s00011-013-0665-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 09/04/2013] [Indexed: 11/29/2022] Open
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Abstract
Oxidized PLs (OxPLs) generated in health and disease are now recognized as important mediators of cellular signalling. There is an increasing body of evidence showing that PL peroxidation is not only increased in vascular disorders, but is also a physiological event of relevance to coagulation, innate immunity, and self-tolerance. Nonenzymatically formed OxPLs generated during chronic inflammation is an uncontrolled event, generating hundreds of diverse structures, and prone to more deleterious bioactivities. In contrast, enzymatic formation of OxPLs is tightly regulated, involving receptors and intracellular signaling, acting as part of the normal physiological response to injury in order to restore homeostasis. In the present review, the major nonenzymatic OxPLs structures found during vascular inflammation are summarized, along with a brief description of their known biological activities. Also, we review what is currently known about enzymatic formation of OxPLs by acutely activated immune cells and their signaling actions under homeostatic and pathological conditions.
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Affiliation(s)
- Maceler Aldrovandi
- Institute of Infection and Immunity, School of Medicine, Cardiff University, Heath Park, Cardiff, CF14 4XN, UK.
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Tamaru S, Mishina H, Watanabe Y, Watanabe K, Fujioka D, Takahashi S, Suzuki K, Nakamura T, Obata JE, Kawabata K, Yokota Y, Murakami M, Hanasaki K, Kugiyama K. Deficiency of phospholipase A2 receptor exacerbates ovalbumin-induced lung inflammation. THE JOURNAL OF IMMUNOLOGY 2013; 191:1021-8. [PMID: 23817419 DOI: 10.4049/jimmunol.1300738] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Secretory phospholipase A2 (sPLA2) plays a critical role in the genesis of lung inflammation through proinflammatory eicosanoids. A previous in vitro experiment showed a possible role of cell surface receptor for sPLA2 (PLA2R) in the clearance of extracellular sPLA2. PLA2R and groups IB and X sPLA2 are expressed in the lung. This study examined a pathogenic role of PLA2R in airway inflammation using PLA2R-deficient (PLA2R(-/-)) mice. Airway inflammation was induced by immunosensitization with OVA. Compared with wild-type (PLA2R(+/+)) mice, PLA2R(-/-) mice had a significantly greater infiltration of inflammatory cells around the airways, higher levels of groups IB and X sPLA2, eicosanoids, and Th2 cytokines, and higher numbers of eosinophils and neutrophils in bronchoalveolar lavage fluid after OVA treatment. In PLA2R(-/-) mice, intratracheally instilled [(125)I]-labeled sPLA2-IB was cleared much more slowly from bronchoalveolar lavage fluid compared with PLA2R(+/+) mice. The degradation of the instilled [(125)I]-labeled sPLA2-IB, as assessed by trichloroacetic acid-soluble radioactivity in bronchoalveolar lavage fluid after instillation, was lower in PLA2R(-/-) mice than in PLA2R(+/+) mice. In conclusion, PLA2R deficiency increased sPLA2-IB and -X levels in the lung through their impaired clearance from the lung, leading to exaggeration of lung inflammation induced by OVA treatment in a murine model.
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Affiliation(s)
- Shun Tamaru
- Department of Internal Medicine II, Faculty of Medicine, University of Yamanashi, Chuo, Yamanashi 409-3898, Japan
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Menschikowski M, Hagelgans A, Schuler U, Froeschke S, Rosner A, Siegert G. Plasma Levels of Phospholipase A2-IIA in Patients with Different Types of Malignancies: Prognosis and Association with Inflammatory and Coagulation Biomarkers. Pathol Oncol Res 2013; 19:839-46. [DOI: 10.1007/s12253-013-9652-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Accepted: 05/05/2013] [Indexed: 12/13/2022]
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Exercise-induced bronchoconstriction. Ann Allergy Asthma Immunol 2013; 110:311-5. [PMID: 23621999 DOI: 10.1016/j.anai.2013.02.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 01/11/2013] [Accepted: 02/04/2013] [Indexed: 01/25/2023]
Abstract
OBJECTIVE To review the literature regarding the pathophysiology of exercise-induced bronchoconstriction (EIB). DATA SOURCES The databases of PubMed, Ovid MEDLINE, and Scopus were searched for articles using the subject headings and/or keywords asthma, exercise-induced/etiology, exercise, mechanism, pathogenesis, and bronchoconstriction. STUDY SELECTIONS Articles were selected based on their relevance to the focus of this review, with emphasis on the specific pathophysiologic mechanisms of EIB. RESULTS EIB occurs in response to the loss of water from the lower airways that results from heating and humidifying large volumes of air in a short period. The resulting hyperosmolar environment activates various cellular mechanisms to release mediators from mast cells, eosinophils, epithelial cells, and sensory nerves. These mediators, in turn, lead to airway smooth muscle contraction and bronchoconstriction. Airway hyperresponsiveness in elite athletes may develop from a process of airway injury and changes in the contractile properties of airway smooth muscle. CONCLUSION EIB commonly affects individuals with and without clinically recognized asthma, especially those who participate in competitive athletics. Through years of research, the pathophysiology of EIB is now better understood and involves a complex interaction between several different cell types and mediators. Continued research to improve the knowledge regarding the mechanisms of EIB should aid the identification, diagnosis, and treatment of this common condition.
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New families of bioactive oxidized phospholipids generated by immune cells: identification and signaling actions. Blood 2012; 120:1985-92. [PMID: 22802337 DOI: 10.1182/blood-2012-04-402826] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Phospholipids are of critical importance in mammalian cell biology, both through providing a permeability barrier and acting as substrates for synthesis of lipid mediators. Recently, several new families of bioactive lipids were identified that form through the enzymatic oxidation of membrane phospholipids in circulating innate immune cells and platelets. These comprise eicosanoids attached to phosphatidylethanolamine and phosphatidylcholine and form within 2-5 minutes of cell activation by pathophysiologic agonists, via the coordinated action of receptors and enzymes. In this review, we summarize what is currently known regarding their structures, mechanisms of formation, cell biology, and signaling actions. We show that phospholipid oxidation by acutely activated immune cells is a controlled event, and we propose a central role in regulating membrane biology and innate immune function during health and disease. We also review the mass spectrometry methods used for identification of the lipids and describe how these approaches can be used for discovery of new lipid mediators in complex biologic samples.
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Oleksowicz L, Liu Y, Bracken RB, Gaitonde K, Burke B, Succop P, Levin L, Dong Z, Lu S. Secretory phospholipase A2-IIa is a target gene of the HER/HER2-elicited pathway and a potential plasma biomarker for poor prognosis of prostate cancer. Prostate 2012; 72:1140-9. [PMID: 22127954 PMCID: PMC3345320 DOI: 10.1002/pros.22463] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Accepted: 11/01/2011] [Indexed: 12/12/2022]
Abstract
BACKGROUND Our previous study showed that prostate cancer cells overexpress and secrete secretory phospholipases A2 group IIa (sPLA2-IIa) and plasma sPLA2-IIa was elevated in prostate cancer patients. The current study further explored the underlying mechanism of sPLA2-IIa overexpression and the potential role of sPLA2-IIa as a prostate cancer biomarker. METHODS Plasma and tissue specimens from prostate cancer patients were analyzed for sPLA2-IIa levels. Regulation of sPLA2-IIa expression by Heregulin-α was determined by Western blot and reporter assay. RESULTS We found that Heregulin-α enhanced expression of the sPLA2-IIa gene via the HER2/HER3-elicited pathway. The EGFR/HER2 dual inhibitor Lapatinib and the NF-kB inhibitor Bortezomib inhibited sPLA2-IIa expression induced by Heregulin-α. Heregulin-α upregulated expression of the sPLA2-IIa gene at the transcriptional level. We further confirmed that plasma sPLA2-IIa secreted by mouse bearing human prostate cancer xenografts reached detectable plasma concentrations. A receiver operating characteristic (ROC) analysis of patient plasma specimens revealed that high levels of plasma sPLA2-IIa, with the optimum cutoff value of 2.0 ng/ml, were significantly associated with high Gleason score (8-10) relative to intermediate Gleason score (6-7) prostate cancers and advanced relative to indolent cancers. The area under the ROC curve (area under curve, AUC) was 0.73 and 0.74, respectively. CONCLUSION We found that Heregulin-α, in addition to EGF, contributes to sPLA2-IIa overexpression in prostate cancer cells. Our findings support the notion that high levels of plasma sPLA2-IIa may serve as a poor prognostic biomarker capable of distinguishing aggressive from indolent prostate cancers, which may improve decision-making and optimize patient management.
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Affiliation(s)
- Leslie Oleksowicz
- Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45237
| | - Yin Liu
- Department of Pathology, University of Cincinnati College of Medicine, Cincinnati, OH 45237
| | - R. Bruce Bracken
- Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, OH 45237
| | - Krishnanath Gaitonde
- Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, OH 45237
| | - Barbara Burke
- Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, OH 45237
| | - Paul Succop
- Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, OH 45237
| | - Linda Levin
- Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, OH 45237
| | - Zhongyun Dong
- Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45237
| | - Shan Lu
- Department of Pathology, University of Cincinnati College of Medicine, Cincinnati, OH 45237
- To whom correspondence should be addressed. Department of Pathology, University of Cincinnati College of Medicine, Building A, Room 259, 2120 East, Galbraith Road, Cincinnati, OH 45237-0507. Phone: 513-558-5109; Fax: 513-558-1312;
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Serum Levels of Secreted Group IIA Phospholipase A2 in Benign Prostatic Hyperplasia and Prostate Cancer: A Biomarker for Inflammation or Neoplasia? Inflammation 2011; 35:1113-8. [DOI: 10.1007/s10753-011-9418-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Plasma secretory phospholipase A2-IIa as a potential biomarker for lung cancer in patients with solitary pulmonary nodules. BMC Cancer 2011; 11:513. [PMID: 22151235 PMCID: PMC3250967 DOI: 10.1186/1471-2407-11-513] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Accepted: 12/09/2011] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Five-year survival for lung cancer has remained at 16% over last several decades largely due to the fact that over 50% of patients are diagnosed with locally-advanced or metastatic disease. Diagnosis at an earlier and potentially curable stage is crucial. Solitary pulmonary nodules (SPNs) are common, but the difficulty lies in the determination of which SPN is malignant. Currently, there is no convenient and reliable biomarker effective for early diagnosis. Secretory phospholipase A2-IIa (sPLA2-IIa) is secreted into the circulation by cancer cells and may allow for an early detection of lung cancer. METHODS Plasma samples from healthy donors, patients with only benign SPN, and patients with lung cancer were analyzed. Expression of sPLA2-IIa protein in lung cancer tissues was also determined. RESULTS We found that the levels of plasma sPLA2-IIa were significantly elevated in lung cancer patients. The receiver operating characteristic curve analysis, comparing lung cancer patients to patients with benign nodules, revealed an optimum cutoff value for plasma sPLA2-IIa of 2.4 ng/ml to predict an early stage cancer with 48% sensitivity and 86% specificity and up to 67% sensitivity for T2 stage lung cancer. Combined sPLA2-IIa, CEA, and Cyfra21.1 tests increased the sensitivity for lung cancer prediction. High level of plasma sPLA2-IIa was associated with a decreased overall cancer survival. sPLA2-IIa was overexpressed in almost all non-small cell lung cancer and in the majority of small cell lung cancer by immunohistochemistry analysis. CONCLUSION Our finding strongly suggests that plasma sPLA2-IIa is a potential lung biomarker to distinguish benign nodules from lung cancer and to aid lung cancer diagnosis in patients with SPNs.
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Sin BA, Akdis M, Zumkehr J, Bezzine S, Bekpen C, Lambeau G, Akdis CA. T-cell and antibody responses to phospholipase A2 from different species show distinct cross-reactivity patterns. Allergy 2011; 66:1513-21. [PMID: 21848517 DOI: 10.1111/j.1398-9995.2011.02689.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Secreted phospholipases A2 (sPLA2) represent antigens to which humans may be rarely or frequently exposed. Thus, the investigation of humoral and cellular immune responses to sPLA2s from different species can provide a suitable model in the study of antibody and T-cell cross-reactivity. METHODS Specific IgE, IgG1, IgG4, and IgA antibodies were analyzed by ELISA against sPLA2s from pancreas of Bos taurus (BT), Apis mellifera (AM) bee venom, Daboia russellii (DR) and Naja mossambica (NM) snake venoms, and human group III (hGIII) sPLA2 using sera of nonallergic beekeepers, AM-allergic patients, and healthy controls. T-cell cross-reactivity was investigated in PBMC, and T-cell clones (TCC) are generated against AM sPLA2. RESULTS Hyperimmune and allergic individuals showed high levels of sPLA2-specific IgG4 and significant IgG4 cross-reactivity between BT, DR, and NM sPLA2s. Furthermore, IgE, IgA, and IgG1 cross-reactivities against BT, DR, and NM sPLA2s were also detectable in the range of 22.2-44.8%. Allergic patients showed significant T-cell proliferative response to NM sPLA2 together with increased IFN-γ and IL-13 production even though they had never been exposed to cobra venom. Although nonallergic healthy controls show no cross-reactivity at T-cell level, they did have low levels of IgG4 and IgA against BT, DR, and NM sPLA2s. Human TCC spanning three major T-cell epitopes of AM sPLA2 showed minor proliferative response to NM and hGIII sPLA2s. CONCLUSIONS This study shows that T cells and antibodies may show cross-reactivity between different species without being naturally exposed to sPLA2s.
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Affiliation(s)
- B A Sin
- Swiss Institute of Allergy and Asthma Research (SIAF), University of Zurich, Davos, Switzerland.
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Hallstrand TS, Lai Y, Ni Z, Oslund RC, Henderson WR, Gelb MH, Wenzel SE. Relationship between levels of secreted phospholipase A₂ groups IIA and X in the airways and asthma severity. Clin Exp Allergy 2011; 41:801-10. [PMID: 21255140 PMCID: PMC3093436 DOI: 10.1111/j.1365-2222.2010.03676.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Background Secreted phospholipase A(2) (sPLA(2) ) may be important mediators of asthma, but the specific sPLA(2) s involved in asthma are not known. Objective To evaluate sPLA(2) group IIA, V, and X proteins (sPLA(2) -IIA, sPLA(2) -V, and sPLA(2) -X) in bronchoalveolar lavage (BAL) fluid, BAL cells, and airway epithelial cells of subjects with and without asthma, and examine the relationship between the levels of specific sPLA(2) enzymes and airway inflammation, asthma severity, and lung function. Methods The expression of sPLA(2) -IIA, sPLA(2) -V, and sPLA(2) -X in BAL cells and epithelial brushings was assessed by qPCR. The levels of these sPLA(2) proteins and sPLA(2) activity with and without group II and group X-specific inhibitors were measured in BAL fluid from 18 controls and 39 asthmatics. Results The airway epithelium expressed sPLA(2) -X at higher levels than either sPLA(2) -IIA or sPLA(2) -V, whereas BAL cells expressed sPLA(2) -IIA and sPLA(2) -X at similar levels. The majority of sPLA(2) activity in BAL fluid was attributed to either sPLA(2) -IIA or sPLA(2) -X. After 10-fold concentration of BAL fluid, the levels of sPLA(2) -X normalized to total protein were increased in asthma and were associated with lung function, the concentration of induced sputum neutrophils, and prostaglandin E(2) . The levels of sPLA(2) -IIA were elevated in asthma when normalized to total protein, but were not related to lung function, markers of airway inflammation or eicosanoid formation. Conclusions and Clinical Relevance These data indicate that sPLA(2) -IIA and sPLA(2) -X are the major sPLA(2) s in human airways, and suggest a link between the levels of sPLA(2) -X in the airways and several features of asthma.
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Affiliation(s)
- T S Hallstrand
- Department of Medicine, Divisions of Pulmonary and Critical Care, University of Washington, Seattle, WA 98195, USA.
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Ji JE, Kim SK, Ahn KH, Choi JM, Jung SY, Jung KM, Jeon HJ, Kim DK. Ceramide induces serotonin release from RBL-2H3 mast cells through calcium mediated activation of phospholipase A2. Prostaglandins Other Lipid Mediat 2011; 94:88-95. [DOI: 10.1016/j.prostaglandins.2011.01.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2010] [Revised: 12/28/2010] [Accepted: 01/04/2011] [Indexed: 11/30/2022]
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Coulthard LG, Costello J, Robinson B, Shiels IA, Taylor SM, Woodruff TM. Comparative efficacy of a secretory phospholipase A2 inhibitor with conventional anti-inflammatory agents in a rat model of antigen-induced arthritis. Arthritis Res Ther 2011; 13:R42. [PMID: 21401925 PMCID: PMC3132024 DOI: 10.1186/ar3278] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 02/10/2011] [Accepted: 03/14/2011] [Indexed: 12/31/2022] Open
Abstract
Introduction Previously, secretory phospholipase A2 (sPLA2) inhibition has been used as an adjunct to conventional rheumatoid arthritis therapy in human clinical trials without significant improvement of arthritic pathology. In this study, we compared the efficacy of a potent and orally active group IIa secretory phospholipase A2 inhibitor (sPLA2I) to conventional anti-arthritic agents; infliximab, leflunomide and prednisolone, in a rat model of antigen-induced arthritis. Methods Initially, to establish efficacy and dose-response, rats were orally dosed with the sPLA2I (1 and 5 mg/kg) two days prior to arthritis induction, and then daily throughout the 14-day study period. In the second trial, rats were orally dosed with the sPLA2I (5 and 10 mg/kg/day) beginning two days after the induction of arthritis, at the peak of joint swelling. Separate groups of rats were also dosed with the tumour necrosis factor-alpha (TNF-α) inhibitor infliximab (single 3 mg/kg i.v. injection), leflunomide (10 mg/kg/day, oral) or prednisolone (1 mg/kg/day, oral) at this same time point and used as comparative treatments. Results In the pathology prevention trial, both 1 and 5 mg/kg dose groups of sPLA2I demonstrated a significant reduction in joint swelling and gait disturbances; however, only the higher 5 mg/kg dose resulted in significantly reduced histopathology scores. In the post-induction trial, rats dosed with sPLA2I showed a significant improvement in joint swelling and gait scoring, whereas none of the conventional therapeutics achieved a significant decrease in both of these two disease markers. Histopathological scoring at the end-point of the study demonstrated significantly reduced median scores in rats treated with 10 mg/kg sPLA2I and leflunomide. Conclusions The results from this study suggest a pathogenic role for sPLA2 enzymes in this model of arthritis in rats, and the potential clinical utility of sPLA2 inhibition as a safer, and more effective, alternative to conventional anti-arthritic therapeutics.
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Affiliation(s)
- Liam G Coulthard
- School of Biomedical Sciences, Research Road, University of Queensland, St, Lucia, Queensland, 4072, Australia
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Murakami M, Taketomi Y, Miki Y, Sato H, Hirabayashi T, Yamamoto K. Recent progress in phospholipase A₂ research: from cells to animals to humans. Prog Lipid Res 2010; 50:152-92. [PMID: 21185866 DOI: 10.1016/j.plipres.2010.12.001] [Citation(s) in RCA: 368] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mammalian genomes encode genes for more than 30 phospholipase A₂s (PLA₂s) or related enzymes, which are subdivided into several classes including low-molecular-weight secreted PLA₂s (sPLA₂s), Ca²+-dependent cytosolic PLA₂s (cPLA₂s), Ca²+-independent PLA₂s (iPLA₂s), platelet-activating factor acetylhydrolases (PAF-AHs), lysosomal PLA₂s, and a recently identified adipose-specific PLA. Of these, the intracellular cPLA₂ and iPLA₂ families and the extracellular sPLA₂ family are recognized as the "big three". From a general viewpoint, cPLA₂α (the prototypic cPLA₂ plays a major role in the initiation of arachidonic acid metabolism, the iPLA₂ family contributes to membrane homeostasis and energy metabolism, and the sPLA₂ family affects various biological events by modulating the extracellular phospholipid milieus. The cPLA₂ family evolved along with eicosanoid receptors when vertebrates first appeared, whereas the diverse branching of the iPLA₂ and sPLA₂ families during earlier eukaryote development suggests that they play fundamental roles in life-related processes. During the past decade, data concerning the unexplored roles of various PLA₂ enzymes in pathophysiology have emerged on the basis of studies using knockout and transgenic mice, the use of specific inhibitors, and information obtained from analysis of human diseases caused by mutations in PLA₂ genes. This review focuses on current understanding of the emerging biological functions of PLA₂s and related enzymes.
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Affiliation(s)
- Makoto Murakami
- Lipid Metabolism Project, The Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan.
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