1
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Tripodi F, Motta Z, Murtas G, Rabattoni V, Nonnis S, Grassi Scalvini F, Rinaldi AM, Rizzi R, Bearzi C, Badone B, Sacchi S, Tedeschi G, Maffioli E, Coccetti P, Pollegioni L. Serine metabolism during differentiation of human iPSC-derived astrocytes. FEBS J 2023; 290:4440-4464. [PMID: 37166453 DOI: 10.1111/febs.16816] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 04/05/2023] [Accepted: 05/10/2023] [Indexed: 05/12/2023]
Abstract
Astrocytes are essential players in development and functions, being particularly relevant as regulators of brain energy metabolism, ionic homeostasis and synaptic transmission. They are also the major source of l-serine in the brain, which is synthesized from the glycolytic intermediate 3-phosphoglycerate through the phosphorylated pathway. l-Serine is the precursor of the two main co-agonists of the N-methyl-d-aspartate receptor, glycine and d-serine. Strikingly, dysfunctions in both l- and d-serine metabolism are associated with neurological and psychiatric disorders. Here, we exploited a differentiation protocol, based on the generation of human mature astrocytes from neural stem cells, and investigated the modification of the proteomic and metabolomic profile during the differentiation process. We show that differentiated astrocytes are more similar to mature rather than to reactive ones, and that axogenesis and pyrimidine metabolism increase up to 30 days along with the folate cycle and sphingolipid metabolism. Consistent with the proliferation and cellular maturation processes that are taking place, also the intracellular levels of l-serine, glycine, threonine, l- and d-aspartate (which level is unexpectedly higher than that of d-serine) show the same biosynthetic time course. A significant utilization of l-serine from the medium is apparent while glycine is first consumed and then released with a peak at 30 days, parallel to its intracellular level. These results underline how metabolism changes during astrocyte differentiation, highlight that d-serine synthesis is restricted in differentiated astrocytes and provide a valuable model for developing potential novel therapeutic approaches to address brain diseases, especially the ones related to serine metabolism alterations.
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Affiliation(s)
- Farida Tripodi
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Italy
| | - Zoraide Motta
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | - Giulia Murtas
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | - Valentina Rabattoni
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | - Simona Nonnis
- DIVAS, Department of Veterinary Medicine and Animal Science, University of Milano, Italy
| | | | | | - Roberto Rizzi
- Fondazione Istituto Nazionale di Genetica Molecolare, Milan, Italy
- Department of Medical-Surgical Science and Biotechnologies, University of Rome La Sapienza, Italy
| | - Claudia Bearzi
- Fondazione Istituto Nazionale di Genetica Molecolare, Milan, Italy
- Institute for Biomedical Technologies, National Research Council of Italy (ITB-CNR), Milan, Italy
| | - Beatrice Badone
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Italy
| | - Silvia Sacchi
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | - Gabriella Tedeschi
- DIVAS, Department of Veterinary Medicine and Animal Science, University of Milano, Italy
- CIMAINA, University of Milano, Italy
| | - Elisa Maffioli
- DIVAS, Department of Veterinary Medicine and Animal Science, University of Milano, Italy
| | - Paola Coccetti
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Italy
| | - Loredano Pollegioni
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
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2
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Bisaccia M, Binda E, Rosini E, Caruso G, Dell'Acqua O, Azzaro M, Laganà P, Tedeschi G, Maffioli EM, Pollegioni L, Marinelli F. A novel promising laccase from the psychrotolerant and halotolerant Antarctic marine Halomonas sp. M68 strain. Front Microbiol 2023; 14:1078382. [PMID: 36846806 PMCID: PMC9950745 DOI: 10.3389/fmicb.2023.1078382] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 01/04/2023] [Indexed: 02/12/2023] Open
Abstract
Microbial communities inhabiting the Antarctic Ocean show psychrophilic and halophilic adaptations conferring interesting properties to the enzymes they produce, which could be exploited in biotechnology and bioremediation processes. Use of cold- and salt-tolerant enzymes allows to limit costs, reduce contaminations, and minimize pretreatment steps. Here, we report on the screening of 186 morphologically diverse microorganisms isolated from marine biofilms and water samples collected in Terra Nova Bay (Ross Sea, Antarctica) for the identification of new laccase activities. After primary screening, 13.4 and 10.8% of the isolates were identified for the ability to oxidize 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and the dye azure B, respectively. Amongst them, the marine Halomonas sp. strain M68 showed the highest activity. Production of its laccase-like activity increased six-fold when copper was added to culture medium. Enzymatic activity-guided separation coupled with mass spectrometry identified this intracellular laccase-like protein (named Ant laccase) as belonging to the copper resistance system multicopper oxidase family. Ant laccase oxidized ABTS and 2,6-dimethoxy phenol, working better at acidic pHs The enzyme showed a good thermostability, with optimal temperature in the 40-50°C range and maintaining more than 40% of its maximal activity even at 10°C. Furthermore, Ant laccase was salt- and organic solvent-tolerant, paving the way for its use in harsh conditions. To our knowledge, this is the first report concerning the characterization of a thermo- and halo-tolerant laccase isolated from a marine Antarctic bacterium.
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Affiliation(s)
- Melissa Bisaccia
- Department of Biotechnology and Life Sciences (DBSV), University of Insubria, Varese, Italy,*Correspondence: Melissa Bisaccia,
| | - Elisa Binda
- Department of Biotechnology and Life Sciences (DBSV), University of Insubria, Varese, Italy
| | - Elena Rosini
- Department of Biotechnology and Life Sciences (DBSV), University of Insubria, Varese, Italy
| | - Gabriella Caruso
- Institute of Polar Sciences (CNR-ISP), National Research Council, Messina, Italy
| | - Ombretta Dell'Acqua
- Institute of Polar Sciences (CNR-ISP), National Research Council, Venice, Italy
| | - Maurizio Azzaro
- Institute of Polar Sciences (CNR-ISP), National Research Council, Messina, Italy
| | - Pasqualina Laganà
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging (BIOMORF), University of Messina, Messina, Italy
| | - Gabriella Tedeschi
- Department of Veterinary Medicine and Animal Science (DIVAS), University of Milan, Milan, Italy,Cimaina, University of Milan, Milan, Italy
| | - Elisa M. Maffioli
- Department of Veterinary Medicine and Animal Science (DIVAS), University of Milan, Milan, Italy,Cimaina, University of Milan, Milan, Italy
| | - Loredano Pollegioni
- Department of Biotechnology and Life Sciences (DBSV), University of Insubria, Varese, Italy
| | - Flavia Marinelli
- Department of Biotechnology and Life Sciences (DBSV), University of Insubria, Varese, Italy
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3
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Dozio E, Maffioli E, Vianello E, Nonnis S, Grassi Scalvini F, Spatola L, Roccabianca P, Tedeschi G, Corsi Romanelli MM. A Wide-Proteome Analysis to Identify Molecular Pathways Involved in Kidney Response to High-Fat Diet in Mice. Int J Mol Sci 2022; 23:ijms23073809. [PMID: 35409168 PMCID: PMC8999052 DOI: 10.3390/ijms23073809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 03/28/2022] [Accepted: 03/29/2022] [Indexed: 11/18/2022] Open
Abstract
The etiopathogenesis of obesity-related chronic kidney disease (CKD) is still scarcely understood. To this aim, we assessed the effect of high-fat diet (HF) on molecular pathways leading to organ damage, steatosis, and fibrosis. Six-week-old male C57BL/6N mice were fed HF diet or normal chow for 20 weeks. Kidneys were collected for genomic, proteomic, histological studies, and lipid quantification. The main findings were as follows: (1) HF diet activated specific pathways leading to fibrosis and increased fatty acid metabolism; (2) HF diet promoted a metabolic shift of lipid metabolism from peroxisomes to mitochondria; (3) no signs of lipid accumulation and/or fibrosis were observed, histologically; (4) the early signs of kidney damage seemed to be related to changes in membrane protein expression; (5) the proto-oncogene MYC was one of the upstream transcriptional regulators of changes occurring in protein expression. These results demonstrated the potential usefulness of specific selected molecules as early markers of renal injury in HF, while histomorphological changes become visible later in obesity-related CDK. The integration of these information with data from biological fluids could help the identification of biomarkers useful for the early detection and prevention of tissue damage in clinical practice.
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Affiliation(s)
- Elena Dozio
- Laboratory of Clinical Pathology, Department of Biomedical Sciences for Health, Università degli Studi di Milano, 20133 Milan, Italy; (E.D.); (M.M.C.R.)
| | - Elisa Maffioli
- Department of Veterinary Medicine and Animal Science, Università degli Studi di Milano, 26900 Lodi, Italy; (E.M.); (S.N.); (F.G.S.); (P.R.); (G.T.)
| | - Elena Vianello
- Laboratory of Clinical Pathology, Department of Biomedical Sciences for Health, Università degli Studi di Milano, 20133 Milan, Italy; (E.D.); (M.M.C.R.)
- Correspondence: ; Tel.: +39-02-50315342
| | - Simona Nonnis
- Department of Veterinary Medicine and Animal Science, Università degli Studi di Milano, 26900 Lodi, Italy; (E.M.); (S.N.); (F.G.S.); (P.R.); (G.T.)
- CRC “Innovation for Well-Being and Environment” (I-WE), Università degli Studi di Milano, 29133 Milan, Italy
| | - Francesca Grassi Scalvini
- Department of Veterinary Medicine and Animal Science, Università degli Studi di Milano, 26900 Lodi, Italy; (E.M.); (S.N.); (F.G.S.); (P.R.); (G.T.)
| | - Leonardo Spatola
- Division of Nephrology, Dialysis and Renal Transplantation, ASST Grande Ospedale Metropolitano Niguarda, 20162 Milan, Italy;
| | - Paola Roccabianca
- Department of Veterinary Medicine and Animal Science, Università degli Studi di Milano, 26900 Lodi, Italy; (E.M.); (S.N.); (F.G.S.); (P.R.); (G.T.)
| | - Gabriella Tedeschi
- Department of Veterinary Medicine and Animal Science, Università degli Studi di Milano, 26900 Lodi, Italy; (E.M.); (S.N.); (F.G.S.); (P.R.); (G.T.)
- CRC “Innovation for Well-Being and Environment” (I-WE), Università degli Studi di Milano, 29133 Milan, Italy
| | - Massimiliano Marco Corsi Romanelli
- Laboratory of Clinical Pathology, Department of Biomedical Sciences for Health, Università degli Studi di Milano, 20133 Milan, Italy; (E.D.); (M.M.C.R.)
- Service of Laboratory Medicine1-Clinical Pathology, IRCCS Policlinico San Donato, 20097 San Donato Milanese, Italy
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4
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Rabattoni V, Pollegioni L, Tedeschi G, Maffioli E, Sacchi S. Cellular studies of the two main isoforms of human d-aspartate oxidase. FEBS J 2021; 288:4939-4954. [PMID: 33650155 DOI: 10.1111/febs.15797] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 01/21/2021] [Accepted: 02/26/2021] [Indexed: 01/01/2023]
Abstract
Human d-aspartate oxidase (hDASPO) is a FAD-dependent enzyme responsible for the degradation of d-aspartate (d-Asp). In the mammalian central nervous system, d-Asp behaves as a classical neurotransmitter, it is thought to be involved in neural development, brain morphology and behavior, and appears to be involved in several pathological states, such as schizophrenia and Alzheimer's disease. Apparently, the human DDO gene produces alternative transcripts encoding for three putative hDASPO isoforms, constituted by 341 (the 'canonical' form), 369, and 282 amino acids. Despite the increasing interest in hDASPO and its physiological role, little is known about these different isoforms. Here, the additional N-terminal peptide present in the hDASPO_369 isoform only has been identified in hippocampus of Alzheimer's disease female patients, while peptides corresponding to the remaining part of the protein were present in samples from male and female healthy controls and Alzheimer's disease patients. The hDASPO_369 isoform was largely expressed in E. coli as insoluble protein, hampering with its biochemical characterization. Furthermore, we generated U87 human glioblastoma cell clones stably expressing hDASPO_341 and, for the first time, hDASPO_369 isoforms; the latter protein showed a lower expression compared with the canonical isoform. Both protein isoforms are active (showing similar kinetic properties), localize to the peroxisomes, are very stable (a half-life of approximately 100 h has been estimated), and are primarily degraded through the ubiquitin-proteasome system. These studies shed light on the properties of hDASPO isoforms with the final aim to clarify the mechanisms controlling brain levels of the neuromodulator d-Asp.
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Affiliation(s)
- Valentina Rabattoni
- "The Protein Factory 2.0", Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, Varese, Italy
| | - Loredano Pollegioni
- "The Protein Factory 2.0", Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, Varese, Italy
| | - Gabriella Tedeschi
- Università degli Studi di Milano, DIMEVET - Dipartimento di Medicina Veterinaria, Milano, Italy
| | - Elisa Maffioli
- Università degli Studi di Milano, DIMEVET - Dipartimento di Medicina Veterinaria, Milano, Italy
| | - Silvia Sacchi
- "The Protein Factory 2.0", Dipartimento di Biotecnologie e Scienze della Vita, Università degli studi dell'Insubria, Varese, Italy
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5
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Dinnes DLM, White MY, Kockx M, Traini M, Hsieh V, Kim M, Hou L, Jessup W, Rye K, Thaysen‐Andersen M, Cordwell SJ, Kritharides L. Human macrophage cathepsin β‐mediated C‐terminal cleavage of apolipoprotein α‐I at Ser
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severely impairs antiatherogenic capacity. FASEB J 2016; 30:4239-4255. [DOI: 10.1096/fj.201600508r] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Accepted: 09/01/2016] [Indexed: 11/11/2022]
Affiliation(s)
| | - Melanie Y. White
- School of Molecular BioscienceDiscipline of Pathology School of Medical Sciences and Charles Perkins Centre University of Sydney Sydney New South Wales Australia
| | - Maaike Kockx
- Atherosclerosis LaboratoryANZAC Research Institute
| | | | - Victar Hsieh
- Department of CardiologySt. George Hospital Sydney New South Wales Australia
| | - Mi‐Jurng Kim
- School of Medical Sciences Sydney New South Wales Australia
| | - Liming Hou
- Lipid Research GroupSchool of Medical Sciences University of New South Wales Sydney New South Wales Australia
| | - Wendy Jessup
- Atherosclerosis LaboratoryANZAC Research Institute
| | - Kerry‐Anne Rye
- Lipid Research GroupSchool of Medical Sciences University of New South Wales Sydney New South Wales Australia
| | - Morten Thaysen‐Andersen
- Department of Chemistry and Biomolecular SciencesFaculty of Science and Engineering Macquarie University Sydney New South Wales Australia
| | - Stuart J. Cordwell
- School of Molecular BioscienceDiscipline of Pathology School of Medical Sciences and Charles Perkins Centre University of Sydney Sydney New South Wales Australia
| | - Leonard Kritharides
- Atherosclerosis LaboratoryANZAC Research Institute
- Department of CardiologyConcord Repatriation General Hospital Sydney New South Wales Australia
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6
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Cubedo J, Padró T, García-Arguinzonis M, Vilahur G, Miñambres I, Pou JM, Ybarra J, Badimon L. A novel truncated form of apolipoprotein A-I transported by dense LDL is increased in diabetic patients. J Lipid Res 2015; 56:1762-73. [PMID: 26168996 DOI: 10.1194/jlr.p057513] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Indexed: 11/20/2022] Open
Abstract
Diabetic (DM) patients have exacerbated atherosclerosis and high CVD burden. Changes in lipid metabolism, lipoprotein structure, and dysfunctional HDL are characteristics of diabetes. Our aim was to investigate whether serum ApoA-I, the main protein in HDL, was biochemically modified in DM patients. By using proteomic technologies, we have identified a 26 kDa ApoA-I form in serum. MS analysis revealed this 26 kDa form as a novel truncated variant lacking amino acids 1-38, ApoA-IΔ(1-38). DM patients show a 2-fold increase in ApoA-IΔ(1-38) over nondiabetic individuals. ApoA-IΔ(1-38) is found in LDL, but not in VLDL or HDL, with an increase in LDL3 and LDL4 subfractions. To identify candidate mechanisms of ApoA-I truncation, we investigated potentially involved enzymes by in silico data mining, and tested the most probable molecule in an established animal model of diabetes. We have found increased hepatic cathepsin D activity as one of the potential proteases involved in ApoA-I truncation. Cathepsin D-cleaved ApoA-I exhibited increased LDL binding affinity and decreased antioxidant activity against LDL oxidation. In conclusion, we show for the first time: a) presence of a novel truncated ApoA-I form, ApoA-IΔ(1-38), in human serum; b) ApoA-IΔ(1-38) is transported by LDL; c) ApoA-IΔ(1-38) is increased in dense LDL fractions of DM patients; and d) cathepsin D-ApoA-I truncation may lead to ApoA-IΔ(1-38) binding to LDLs, increasing their susceptibility to oxidation and contributing to the high cardiovascular risk of DM patients.
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Affiliation(s)
- Judit Cubedo
- Cardiovascular Research Center (CSIC-ICCC), Biomedical Research Institute Sant Pau (IIB-Sant Pau), Barcelona, Spain
| | - Teresa Padró
- Cardiovascular Research Center (CSIC-ICCC), Biomedical Research Institute Sant Pau (IIB-Sant Pau), Barcelona, Spain
| | - Maisa García-Arguinzonis
- Cardiovascular Research Center (CSIC-ICCC), Biomedical Research Institute Sant Pau (IIB-Sant Pau), Barcelona, Spain
| | - Gemma Vilahur
- Cardiovascular Research Center (CSIC-ICCC), Biomedical Research Institute Sant Pau (IIB-Sant Pau), Barcelona, Spain
| | - Inka Miñambres
- Endocrinology Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Jose María Pou
- Endocrinology Department, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | | | - Lina Badimon
- Cardiovascular Research Center (CSIC-ICCC), Biomedical Research Institute Sant Pau (IIB-Sant Pau), Barcelona, Spain Cardiovascular Research Chair, Universitat Autònoma de Barcelona, Barcelona, Spain
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7
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Das M, Mei X, Jayaraman S, Atkinson D, Gursky O. Amyloidogenic mutations in human apolipoprotein A-I are not necessarily destabilizing - a common mechanism of apolipoprotein A-I misfolding in familial amyloidosis and atherosclerosis. FEBS J 2014; 281:2525-42. [PMID: 24702826 DOI: 10.1111/febs.12809] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 03/19/2014] [Accepted: 04/04/2014] [Indexed: 12/18/2022]
Abstract
High-density lipoproteins and their major protein, apolipoprotein A-I (apoA-I), remove excess cellular cholesterol and protect against atherosclerosis. However, in acquired amyloidosis, nonvariant full-length apoA-I deposits as fibrils in atherosclerotic plaques; in familial amyloidosis, N-terminal fragments of variant apoA-I deposit in vital organs, damaging them. Recently, we used the crystal structure of Δ(185-243)apoA-I to show that amyloidogenic mutations destabilize apoA-I and increase solvent exposure of the extended strand 44-55 that initiates β-aggregation. In the present study, we test this hypothesis by exploring naturally occurring human amyloidogenic mutations, W50R and G26R, within or close to this strand. The mutations caused small changes in the protein's α-helical content, stability, proteolytic pattern and protein-lipid interactions. These changes alone were unlikely to account for amyloidosis, suggesting the importance of other factors. Sequence analysis predicted several amyloid-prone segments that can initiate apoA-I misfolding. Aggregation studies using N-terminal fragments verified this prediction experimentally. Three predicted N-terminal amyloid-prone segments, mapped on the crystal structure, formed an α-helical cluster. Structural analysis indicates that amyloidogenic mutations or Met86 oxidation perturb native packing in this cluster. Taken together, the results suggest that structural perturbations in the amyloid-prone segments trigger α-helix to β-sheet conversion in the N-terminal ~ 75 residues forming the amyloid core. Polypeptide outside this core can be proteolysed to form 9-11 kDa N-terminal fragments found in familial amyloidosis. Our results imply that apoA-I misfolding in familial and acquired amyloidosis follows a similar mechanism that does not require significant structural destabilization or proteolysis. This novel mechanism suggests potential therapeutic interventions for apoA-I amyloidosis.
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Affiliation(s)
- Madhurima Das
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA, USA
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8
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Cavigiolio G, Jayaraman S. Proteolysis of apolipoprotein A-I by secretory phospholipase A₂: a new link between inflammation and atherosclerosis. J Biol Chem 2014; 289:10011-23. [PMID: 24523407 DOI: 10.1074/jbc.m113.525717] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
In the acute phase of the inflammatory response, secretory phospholipase A2 (sPLA2) reaches its maximum levels in plasma, where it is mostly associated with high density lipoproteins (HDL). Overexpression of human sPLA2 in transgenic mice reduces both HDL cholesterol and apolipoprotein A-I (apoA-I) plasma levels through increased HDL catabolism by an unknown mechanism. To identify unknown PLA2-mediated activities on the molecular components of HDL, we characterized the protein and lipid products of the PLA2 reaction with HDL. Consistent with previous studies, hydrolysis of HDL phospholipids by PLA2 reduced the particle size without changing its protein composition. However, when HDL was destabilized in the presence of PLA2 by the action of cholesteryl ester transfer protein or by guanidine hydrochloride treatment, a fraction of apoA-I, but no other proteins, dissociated from the particle and was rapidly cleaved. Incubation of PLA2 with lipid-free apoA-I produced similar protein fragments in the range of 6-15 kDa, suggesting specific and direct reaction of PLA2 with apoA-I. Mass spectrometry analysis of isolated proteolytic fragments indicated at least two major cleavage sites at the C-terminal and the central domain of apoA-I. ApoA-I proteolysis by PLA2 was Ca(2+)-independent, implicating a different mechanism from the Ca(2+)-dependent PLA2-mediated phospholipid hydrolysis. Inhibition of proteolysis by benzamidine suggests that the proteolytic and lipolytic activities of PLA2 proceed through different mechanisms. Our study identifies a previously unknown proteolytic activity of PLA2 that is specific to apoA-I and may contribute to the enhanced catabolism of apoA-I in inflammation and atherosclerosis.
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Affiliation(s)
- Giorgio Cavigiolio
- From the Children's Hospital Oakland Research Institute, Oakland, California 94609 and
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9
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Daniil G, Zannis VI, Chroni A. Effect of apoA-I Mutations in the Capacity of Reconstituted HDL to Promote ABCG1-Mediated Cholesterol Efflux. PLoS One 2013; 8:e67993. [PMID: 23826352 PMCID: PMC3694867 DOI: 10.1371/journal.pone.0067993] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 05/23/2013] [Indexed: 12/29/2022] Open
Abstract
ATP binding cassette transporter G1 (ABCG1) mediates the cholesterol transport from cells to high-density lipoprotein (HDL), but the role of apolipoprotein A-I (apoA-I), the main protein constituent of HDL, in this process is not clear. To address this, we measured cholesterol efflux from HEK293 cells or J774 mouse macrophages overexpressing ABCG1 using as acceptors reconstituted HDL (rHDL) containing wild-type or various mutant apoA-I forms. It was found that ABCG1-mediated cholesterol efflux was severely reduced (by 89%) when using rHDL containing the carboxyl-terminal deletion mutant apoA-I[Δ(185–243)]. ABCG1-mediated cholesterol efflux was not affected or moderately decreased by rHDL containing amino-terminal deletion mutants and several mid-region deletion or point apoA-I mutants, and was restored to 69–99% of control by double deletion mutants apoA-I[Δ(1–41)Δ(185–243)] and apoA-I[Δ(1–59)Δ(185–243)]. These findings suggest that the central helices alone of apoA-I associated to rHDL can promote ABCG1-mediated cholesterol efflux. Further analysis showed that rHDL containing the carboxyl-terminal deletion mutant apoA-I[Δ(185–243)] only slightly reduced (by 22%) the ABCG1-mediated efflux of 7-ketocholesterol, indicating that depending on the sterol type, structural changes in rHDL-associated apoA-I affect differently the ABCG1-mediated efflux of cholesterol and 7-ketocholesterol. Overall, our findings demonstrate that rHDL-associated apoA-I structural changes affect the capacity of rHDL to accept cellular cholesterol by an ABCG1-mediated process. The structure-function relationship seen here between rHDL-associated apoA-I mutants and ABCG1-mediated cholesterol efflux closely resembles that seen before in lipid-free apoA-I mutants and ABCA1-dependent cholesterol efflux, suggesting that both processes depend on the same structural determinants of apoA-I.
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Affiliation(s)
- Georgios Daniil
- Institute of Biosciences and Applications, National Center for Scientific Research “Demokritos”, Agia Paraskevi, Athens, Greece
| | - Vassilis I. Zannis
- Molecular Genetics, Departments of Medicine and Biochemistry, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts, United States of America
| | - Angeliki Chroni
- Institute of Biosciences and Applications, National Center for Scientific Research “Demokritos”, Agia Paraskevi, Athens, Greece
- * E-mail:
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10
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Eberini I, Wait R, Calabresi L, Sensi C, Miller I, Gianazza E. A proteomic portrait of atherosclerosis. J Proteomics 2013; 82:92-112. [DOI: 10.1016/j.jprot.2013.02.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 02/11/2013] [Accepted: 02/13/2013] [Indexed: 01/11/2023]
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11
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Gomaraschi M, Ossoli A, Vitali C, Pozzi S, Vitali Serdoz L, Pitzorno C, Sinagra G, Franceschini G, Calabresi L. Off-target effects of thrombolytic drugs: apolipoprotein A-I proteolysis by alteplase and tenecteplase. Biochem Pharmacol 2012; 85:525-30. [PMID: 23219857 DOI: 10.1016/j.bcp.2012.11.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 11/21/2012] [Accepted: 11/26/2012] [Indexed: 11/29/2022]
Abstract
The administration of thrombolytic drugs is of proven benefit in a variety of clinical conditions requiring acute revascularization, including acute myocardial infarction (AMI), ischemic stroke, pulmonary embolism, and venous thrombosis. Generated plasmin can degrade non-target proteins, including apolipoprotein A-I (apoA-I), the major protein constituent of high-density lipoproteins (HDL). Aim of the present study was to compare the extent of apoA-I proteolytic degradation in AMI patients treated with two thrombolytic drugs, alteplase and the genetically engineered t-PA variant tenecteplase. ApoA-I degradation was evaluated in sera from 38 AMI patients treated with alteplase or tenecteplase. In vitro, apoA-I degradation was tested by incubating control sera or purified HDL with alteplase or tenecteplase at different concentrations (5-100 μg/ml). Treatment with alteplase and tenecteplase results in apoA-I proteolysis; the extent of apoA-I degradation was more pronounced in alteplase-treated patients than in tenecteplase-treated patients. In vitro, the extent of apoA-I proteolysis was higher in alteplase-treated sera than in tenecteplase-treated sera, in the whole drug concentration range. No direct effect of the two thrombolytic agents on apoA-I degradation was observed. In addition to apoA-I, apoA-IV was also degraded by the two thrombolytic agents and again proteolytic degradation was higher with alteplase than tenecteplase. In conclusion, this study indicates that both alteplase and tenecteplase cause plasmin-mediated proteolysis of apoA-I, with alteplase resulting in a greater apoA-I degradation than tenecteplase, potentially causing a transient impairment of HDL atheroprotective functions.
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Affiliation(s)
- Monica Gomaraschi
- Centro Enrica Grossi Paoletti, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano, Italy
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12
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Cho KH. 1,8-cineole protected human lipoproteins from modification by oxidation and glycation and exhibited serum lipid-lowering and anti-inflammatory activity in zebrafish. BMB Rep 2012; 45:565-70. [DOI: 10.5483/bmbrep.2012.45.10.044] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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13
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Lee-Rueckert M, Kovanen PT. Extracellular modifications of HDL in vivo and the emerging concept of proteolytic inactivation of preβ-HDL. Curr Opin Lipidol 2011; 22:394-402. [PMID: 21881503 DOI: 10.1097/mol.0b013e32834a3d24] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
PURPOSE OF REVIEW Both quantity and quality of the circulating HDL particle matter for the optimal antiatherogenic potential of HDL. This review summarizes various mechanisms capable of inducing extracellular modifications of HDL and reducing the function of HDL subclasses as cholesterol acceptors. Special emphasis is laid on the proteolytic inactivation of lipid-poor preβ-migrating HDL (preβ-HDL). RECENT FINDINGS HDL particles can undergo functional inactivation in vivo. During atherogenesis, different cell types in the arterial intima release enzymes into the intimal fluid, potentially capable of causing structural and chemical modifications of the various components present in the lipid core or in the polar surface of the HDL particles. Enzymatic oxidation, lipolysis and proteolysis, and nonenzymatic glycosylation are among the HDL modifications that adversely affect HDL functionality. Proteolysis of preβ-HDL by various proteases present in the arterial intima has emerged as a potential mechanism that impairs the efficiency of HDL to promote cholesterol efflux from macrophage foam cells, the mast cell-derived neutral protease chymase being a prime example of such impairment. A paradigm of proteolytic inactivation of preβ-HDL in vivo is emerging. SUMMARY Several extracellular enzymes present in the arterial intima may compromise various cardioprotective functions of HDL. Observations on proteolysis of specific lipid-poor HDL subpopulations in vivo constitute the basis for future studies evaluating the actual impact of proteolytic microenvironments on the initiation and progression of atherosclerotic lesions.
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Ramella NA, Rimoldi OJ, Prieto ED, Schinella GR, Sanchez SA, Jaureguiberry MS, Vela ME, Ferreira ST, Tricerri MA. Human apolipoprotein A-I-derived amyloid: its association with atherosclerosis. PLoS One 2011; 6:e22532. [PMID: 21811627 PMCID: PMC3139661 DOI: 10.1371/journal.pone.0022532] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Accepted: 06/23/2011] [Indexed: 01/08/2023] Open
Abstract
Amyloidoses constitute a group of diseases in which soluble proteins aggregate and deposit extracellularly in tissues. Nonhereditary apolipoprotein A-I (apoA-I) amyloid is characterized by deposits of nonvariant protein in atherosclerotic arteries. Despite being common, little is known about the pathogenesis and significance of apoA-I deposition. In this work we investigated by fluorescence and biochemical approaches the impact of a cellular microenvironment associated with chronic inflammation on the folding and pro-amyloidogenic processing of apoA-I. Results showed that mildly acidic pH promotes misfolding, aggregation, and increased binding of apoA-I to extracellular matrix elements, thus favoring protein deposition as amyloid like-complexes. In addition, activated neutrophils and oxidative/proteolytic cleavage of the protein give rise to pro amyloidogenic products. We conclude that, even though apoA-I is not inherently amyloidogenic, it may produce non hereditary amyloidosis as a consequence of the pro-inflammatory microenvironment associated to atherogenesis.
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Affiliation(s)
- Nahuel A. Ramella
- Instituto de Investigaciones Bioquímicas La Plata (INIBIOLP), CCT-CONICET, La Plata, Argentina
- Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - Omar J. Rimoldi
- Instituto de Investigaciones Bioquímicas La Plata (INIBIOLP), CCT-CONICET, La Plata, Argentina
- Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - Eduardo D. Prieto
- Instituto de Investigaciones Bioquímicas La Plata (INIBIOLP), CCT-CONICET, La Plata, Argentina
- Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - Guillermo R. Schinella
- Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - Susana A. Sanchez
- Laboratory for Fluorescence Dynamics, University of California Irvine, Irvine, California, United States of America
- Microscopy Unit, Fundación CNIC-Carlos III, Centro Nacional de Investigaciones Cardiovasculares, Madrid, España
| | - María S. Jaureguiberry
- Instituto de Investigaciones Bioquímicas La Plata (INIBIOLP), CCT-CONICET, La Plata, Argentina
- Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - María E. Vela
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA), Universidad Nacional de La Plata-CCT-CONICET, La Plata, Argentina
| | - Sergio T. Ferreira
- Program in Biochemistry and Cellular Biophysics, Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - M. Alejandra Tricerri
- Instituto de Investigaciones Bioquímicas La Plata (INIBIOLP), CCT-CONICET, La Plata, Argentina
- Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
- * E-mail:
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Jang W, Jeoung NH, Cho KH. Modified apolipoprotein (apo) A-I by artificial sweetener causes severe premature cellular senescence and atherosclerosis with impairment of functional and structural properties of apoA-I in lipid-free and lipid-bound state. Mol Cells 2011; 31:461-70. [PMID: 21533907 PMCID: PMC3887604 DOI: 10.1007/s10059-011-1009-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Revised: 02/21/2011] [Accepted: 03/03/2011] [Indexed: 01/28/2023] Open
Abstract
Long-term consumption of artificial sweeteners (AS) has been the recent focus of safety concerns. However, the potential risk of the AS in cardiovascular disease and lipoprotein metabolism has not been investigated sufficiently. We compared the influence of AS (aspartame, acesulfame K, and saccharin) and fructose in terms of functional and structural correlations of apolipoprotein (apo) A-I and high-density lipoproteins (HDL), which have atheroprotective effects. Long-term treatment of apoA-I with the sweetener at physiological concentration (3 mM for 168 h) resulted in loss of antioxidant and phospholipid binding activities with modification of secondary structure. The AS treated apoA-I exhibited proteolytic cleavage to produce 26 kDa-fragment. They showed pro-atherogenic properties in acetylated LDL phagocytosis of macrophages. Each sweetener alone or sweetener-treated apoA-I caused accelerated senescence in human dermal fibroblasts. These results suggest that long-term consumption of AS might accelerate atherosclerosis and senescence via impairment of function and structure of apoA-I and HDL.
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Affiliation(s)
- Wookju Jang
- School of Biotechnology, Yeungnam University, Gyeongsan 712-749, Korea
- These authors contributed equally to this work
| | - Nam Ho Jeoung
- Department of Fundamental Medical and Pharmaceutical Sciences, CULeaders College, Catholic University of Daegu, Gyeongsan 712-702, Korea
- These authors contributed equally to this work
| | - Kyung-Hyun Cho
- School of Biotechnology, Yeungnam University, Gyeongsan 712-749, Korea
- Research Institute of Protein Sensor, Yeungnam University, Gyeongsan 712-749, Korea
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Rocco AG, Sensi C, Gianazza E, Calabresi L, Franceschini G, Sirtori CR, Eberini I. Structural and dynamic features of apolipoprotein A-I cysteine mutants, Milano and Paris, in synthetic HDL. J Mol Graph Model 2010; 29:406-14. [DOI: 10.1016/j.jmgm.2010.08.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Revised: 07/29/2010] [Accepted: 08/05/2010] [Indexed: 12/16/2022]
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17
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Park KH, Shin DG, Kim JR, Cho KH. Senescence-Related Truncation and Multimerization of Apolipoprotein A-I in High-Density Lipoprotein With an Elevated Level of Advanced Glycated End Products and Cholesteryl Ester Transfer Activity. J Gerontol A Biol Sci Med Sci 2010; 65:600-10. [DOI: 10.1093/gerona/glq034] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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18
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Ndao M, Spithill TW, Caffrey R, Li H, Podust VN, Perichon R, Santamaria C, Ache A, Duncan M, Powell MR, Ward BJ. Identification of novel diagnostic serum biomarkers for Chagas' disease in asymptomatic subjects by mass spectrometric profiling. J Clin Microbiol 2010; 48:1139-49. [PMID: 20071547 PMCID: PMC2849606 DOI: 10.1128/jcm.02207-09] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2009] [Revised: 12/26/2009] [Accepted: 01/07/2010] [Indexed: 01/10/2023] Open
Abstract
More than 10 million people are thought to be infected with Trypanosoma cruzi, primarily in the Americas. The clinical manifestations of Chagas' disease (CD) are variable, but most subjects remain asymptomatic for decades. Only 15 to 30% eventually develop terminal complications. All current diagnostic tests have limitations. New approaches are needed for blood bank screening as well as for improved diagnosis and prognosis. Sera from subjects with asymptomatic CD (n = 131) were compared to those from uninfected controls (n = 164) and subjects with other parasitic diseases (n = 140), using protein array mass spectrometry. To identify biomarkers associated with CD, sera were fractionated by anion-exchange chromatography and bound to two commercial ProteinChip array chemistries: WCX2 and IMAC3. Multiple candidate biomarkers were found in CD sera (3 to 75.4 kDa). Algorithms employing 3 to 5 of these biomarkers achieved up to 100% sensitivity and 98% specificity for CD. The biomarkers most useful for diagnosis were identified and validated. These included MIP1 alpha, C3a anaphylatoxin, and unusually truncated forms of fibronectin, apolipoprotein A1 (ApoA1), and C3. An antipeptide antiserum against the 28.9-kDa C terminus of the fibronectin fragment achieved good specificity (90%) for CD in a Western blot format. We identified full-length ApoA1 (28.1 kDa), the major structural and functional protein component of high-density lipoprotein (HDL), as an important negative biomarker for CD, and relatively little full-length ApoA1 was detected in CD sera. This work provides proof of principle that both platform-dependent (i.e., mass spectrometry-based) and platform-independent (i.e., Western blot) tests can be generated using high-throughput mass profiling.
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Affiliation(s)
- Momar Ndao
- National Reference Centre for Parasitology, Research Institute of the McGill University Health Center, Montreal, Quebec, Canada.
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Apolipoprotein A-I from striped bass (Morone saxatilis) demonstrates antibacterial activity in vitro. Comp Biochem Physiol B Biochem Mol Biol 2008; 151:167-75. [PMID: 18627791 DOI: 10.1016/j.cbpb.2008.06.011] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2008] [Revised: 06/24/2008] [Accepted: 06/24/2008] [Indexed: 11/24/2022]
Abstract
HDL and apolipoprotein A-I from teleostean fishes demonstrate in vitro activity against gram-positive and gram-negative bacteria. In this study, we purified ApoA-1 from striped bass (Morone saxatilis) plasma and examined its in vitro antibacterial activity against Streptococcus sp., Escherichia coli, and Mycobacterium marinum. In addition, we obtained sequence for a putative striped bass ApoA-1 gene, which when translated contained the identical sequence generated from N-terminal sequencing of the purified ApoA-1. The predicted secondary and tertiary structures contained the characteristic proline residues and high alpha-helical content conserved between mammals and fishes. Purified ApoA-1 exhibited antibacterial activity against the bacteria assayed. Concentrations of 125 microg/mL for E. coli, 250 microg/mL for Streptococcus sp., and 250 microg/mL for M. marinum, inhibited bacterial growth by 50% compared to control. ApoA-1 plasma concentrations in experimental and wild fish ranged from undetectable levels to greater than 5 mg/mL, indicating that striped bass ApoA-1 is an effective antibacterial agent at concentrations below the range of physiological concentrations in striped bass plasma. We therefore conclude that ApoA-1 could play a role in innate defense against bacterial pathogens in striped bass.
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Lee-Rueckert M, Kovanen PT. Mast cell proteases: Physiological tools to study functional significance of high density lipoproteins in the initiation of reverse cholesterol transport. Atherosclerosis 2006; 189:8-18. [PMID: 16530202 DOI: 10.1016/j.atherosclerosis.2006.02.014] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2005] [Revised: 01/17/2006] [Accepted: 02/01/2006] [Indexed: 11/27/2022]
Abstract
The extracellular fluid of the intima is rich in lipid-poor species of high density lipoproteins (HDL) that promote efficient efflux of cholesterol from macrophages. Yet, during atherogenesis, cholesterol accumulates in macrophages, and foam cells are formed. We have studied proteolytic modification of HDL by mast cell proteases as a potential mechanism of reduced cholesterol efflux from foam cells. Mast cells are present in human atherosclerotic lesions and, when activated, they expel cytoplasmic granules that are filled with heparin proteoglycans and two neutral proteases, chymase and tryptase. Both proteases were found to specifically deplete in vitro the apoA-I-containing prebeta-migrating HDL (prebeta-HDL) and other lipid-poor HDL particles that contain only apoA-IV or apoE. These losses led to inhibition of the high-affinity component of cholesterol efflux from macrophage foam cells facilitated by the ATP-binding cassette transporter A1 (ABCA1). In contrast, the diffusional component of efflux promoted by alpha-HDL particles was not changed after proteolysis. Mast cell proteases are providing new insights into the role of extracellular proteolysis of HDL as an inhibiting principle of the initial steps of reverse cholesterol transport in the atherosclerotic intima, where many types of protease-secreting cells are present.
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Norata GD, Pirillo A, Catapano AL. Modified HDL: biological and physiopathological consequences. Nutr Metab Cardiovasc Dis 2006; 16:371-386. [PMID: 16829346 DOI: 10.1016/j.numecd.2006.01.012] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2005] [Accepted: 01/03/2006] [Indexed: 01/26/2023]
Abstract
Epidemiological and clinical studies have demonstrated the inverse association between HDL cholesterol levels (HDL-C) and the risk of coronary heart disease (CHD). This correlation is believed to relate to the ability of HDL to promote reverse cholesterol transport. Remodeling of HDL due to chemical/physical modifications can dramatically affect its functions, leading to dysfunctional HDL that could promote atherogenesis. HDL modification can be achieved by different means: (i) non-enzymatic modifications, owing to the presence of free metal ions in the atherosclerotic plaques; (ii) cell-associated enzymes, which can degrade the apoproteins without significant changes in the lipid moiety, or can alternatively induce apoprotein cross-linking and lipid oxidation; (iii) association with acute phase proteins, whose circulating levels are significantly increased during inflammation which may modify HDL structure and functions; and (iv) metabolic modifications, such as glycation that occurs under hyperglycaemic conditions. Available data suggest that HDL can easily be modified losing their anti-atherogenic activities. These observation results mainly from in vitro studies, while few in vivo data, are available. Furthermore the in vivo mechanisms involved in HDL modification are ill understood. A better knowledge of these pathways may provide possible therapeutic target aimed at reducing HDL modification.
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