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Sampson T. Microbial amyloids in neurodegenerative amyloid diseases. FEBS J 2023:10.1111/febs.17023. [PMID: 38041542 PMCID: PMC11144261 DOI: 10.1111/febs.17023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 11/13/2023] [Accepted: 11/30/2023] [Indexed: 12/03/2023]
Abstract
Human-disease associated amyloidogenic proteins are not unique in their ability to form amyloid fibrillar structures. Numerous microbes produce amyloidogenic proteins that have distinct functions for their physiology in their amyloid form, rather than solely detrimental. Emerging data indicate associations between various microbial organisms, including those which produce functional amyloids, with neurodegenerative diseases. Here, we review some of the evidence suggesting that microbial amyloids impact amyloid disease in host organisms. Experimental data are building a foundation for continued lines of enquiry and suggest that that direct or indirect interactions between microbial and host amyloids may be a contributor to amyloid pathologies. Inhibiting microbial amyloids or their interactions with the host may therefore represent a tangible target to limit various amyloid pathologies.
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Affiliation(s)
- Timothy Sampson
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, USA
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, USA
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2
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Wirth F, Heitz FD, Seeger C, Combaluzier I, Breu K, Denroche HC, Thevenet J, Osto M, Arosio P, Kerr-Conte J, Verchere CB, Pattou F, Lutz TA, Donath MY, Hock C, Nitsch RM, Grimm J. A human antibody against pathologic IAPP aggregates protects beta cells in type 2 diabetes models. Nat Commun 2023; 14:6294. [PMID: 37813862 PMCID: PMC10562398 DOI: 10.1038/s41467-023-41986-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 09/26/2023] [Indexed: 10/11/2023] Open
Abstract
In patients with type 2 diabetes, pancreatic beta cells progressively degenerate and gradually lose their ability to produce insulin and regulate blood glucose. Beta cell dysfunction and loss is associated with an accumulation of aggregated forms of islet amyloid polypeptide (IAPP) consisting of soluble prefibrillar IAPP oligomers as well as insoluble IAPP fibrils in pancreatic islets. Here, we describe a human monoclonal antibody selectively targeting IAPP oligomers and neutralizing IAPP aggregate toxicity by preventing membrane disruption and apoptosis in vitro. Antibody treatment in male rats and mice transgenic for human IAPP, and human islet-engrafted mouse models of type 2 diabetes triggers clearance of IAPP oligomers resulting in beta cell protection and improved glucose control. These results provide new evidence for the pathological role of IAPP oligomers and suggest that antibody-mediated removal of IAPP oligomers could be a pharmaceutical strategy to support beta cell function in type 2 diabetes.
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Affiliation(s)
- Fabian Wirth
- Neurimmune AG, Wagistrasse 18, 8952, Schlieren, Switzerland
| | | | | | | | - Karin Breu
- Neurimmune AG, Wagistrasse 18, 8952, Schlieren, Switzerland
| | - Heather C Denroche
- BC Children's Hospital Research Institute and Centre for Molecular Medicine and Therapeutics, Departments of Surgery and Pathology & Laboratory Medicine, University of British Columbia, A4-151 950 W 28 Ave, Vancouver, BC, Canada
| | - Julien Thevenet
- Univ-Lille, Inserm, CHU Lille, U1190 - EGID, F-59000, Lille, France
| | - Melania Osto
- Institute of Veterinary Physiology, Vetsuisse Faculty of the University of Zürich, Winterthurerstrasse 260, 8057, Zürich, Switzerland
| | - Paolo Arosio
- Institute for Chemical and Bioengineering, ETH Zürich, Vladimir-Prelog-Weg 1-5/10, 8093, Zürich, Switzerland
| | - Julie Kerr-Conte
- Univ-Lille, Inserm, CHU Lille, U1190 - EGID, F-59000, Lille, France
| | - C Bruce Verchere
- BC Children's Hospital Research Institute and Centre for Molecular Medicine and Therapeutics, Departments of Surgery and Pathology & Laboratory Medicine, University of British Columbia, A4-151 950 W 28 Ave, Vancouver, BC, Canada
| | - François Pattou
- Univ-Lille, Inserm, CHU Lille, U1190 - EGID, F-59000, Lille, France
| | - Thomas A Lutz
- Institute of Veterinary Physiology, Vetsuisse Faculty of the University of Zürich, Winterthurerstrasse 260, 8057, Zürich, Switzerland
| | - Marc Y Donath
- Clinic for Endocrinology, Diabetes & Metabolism, and Department of Biomedicine, University Hospital Basel, Hebelstrasse 20, 4031, Basel, Switzerland
| | - Christoph Hock
- Neurimmune AG, Wagistrasse 18, 8952, Schlieren, Switzerland
- Institute for Regenerative Medicine-IREM, University of Zürich, Wagistrasse 12, 8952, Schlieren, Switzerland
| | - Roger M Nitsch
- Neurimmune AG, Wagistrasse 18, 8952, Schlieren, Switzerland
- Institute for Regenerative Medicine-IREM, University of Zürich, Wagistrasse 12, 8952, Schlieren, Switzerland
| | - Jan Grimm
- Neurimmune AG, Wagistrasse 18, 8952, Schlieren, Switzerland.
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3
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Wang HW, Tang J, Sun L, Li Z, Deng M, Dai Z. Mechanism of immune attack in the progression of obesity-related type 2 diabetes. World J Diabetes 2023; 14:494-511. [PMID: 37273249 PMCID: PMC10236992 DOI: 10.4239/wjd.v14.i5.494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 03/06/2023] [Accepted: 03/30/2023] [Indexed: 05/15/2023] Open
Abstract
Obesity and overweight are widespread issues in adults, children, and adolescents globally, and have caused a noticeable rise in obesity-related complications such as type 2 diabetes mellitus (T2DM). Chronic low-grade inflammation is an important promotor of the pathogenesis of obesity-related T2DM. This proinflammatory activation occurs in multiple organs and tissues. Immune cell-mediated systemic attack is considered to contribute strongly to impaired insulin secretion, insulin resistance, and other metabolic disorders. This review focused on highlighting recent advances and underlying mechanisms of immune cell infiltration and inflammatory responses in the gut, islet, and insulin-targeting organs (adipose tissue, liver, skeletal muscle) in obesity-related T2DM. There is current evidence that both the innate and adaptive immune systems contribute to the development of obesity and T2DM.
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Affiliation(s)
- Hua-Wei Wang
- Department of Endocrinology, Zhongnan Hospital of Wuhan University, Wuhan 430071, Hubei Province, China
| | - Jun Tang
- Department of Endocrinology, Zhongnan Hospital of Wuhan University, Wuhan 430071, Hubei Province, China
| | - Li Sun
- Department of Endocrinology, Zhongnan Hospital of Wuhan University, Wuhan 430071, Hubei Province, China
| | - Zhen Li
- Department of Hepatobiliary and Pancreatic Surgery, Zhongnan Hospital of Wuhan University, Wuhan 430071, Hubei Province, China
| | - Ming Deng
- Department of Radiology, Zhongnan Hospital of Wuhan University, Wuhan 430071, Hubei Province, China
| | - Zhe Dai
- Department of Endocrinology, Zhongnan Hospital of Wuhan University, Wuhan 430071, Hubei Province, China
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4
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Alrouji M, Al-Kuraishy HM, Al-Gareeb AI, Alexiou A, Papadakis M, Saad HM, Batiha GES. The potential role of human islet amyloid polypeptide in type 2 diabetes mellitus and Alzheimer's diseases. Diabetol Metab Syndr 2023; 15:101. [PMID: 37173803 PMCID: PMC10182652 DOI: 10.1186/s13098-023-01082-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 05/08/2023] [Indexed: 05/15/2023] Open
Abstract
Human Islet amyloid polypeptide (hIAPP) from pancreatic β cells in the islet of Langerhans has different physiological functions including inhibiting the release of insulin and glucagon. Type 2 diabetes mellitus (T2DM) is an endocrine disorder due to relative insulin insufficiency and insulin resistance (IR) is associated with increased circulating hIAPP. Remarkably, hIAPP has structural similarity with amyloid beta (Aβ) and can engage in the pathogenesis of T2DM and Alzheimer's disease (AD). Therefore, the present review aimed to elucidate how hIAPP acts as a link between T2DM and AD. IR, aging and low β cell mass increase expression of hIAPP which binds cell membrane leading to the aberrant release of Ca2+ and activation of the proteolytic enzymes leading to a series of events causing loss of β cells. Peripheral hIAPP plays a major role in the pathogenesis of AD, and high circulating hIAPP level increase AD risk in T2DM patients. However, there is no hard evidence for the role of brain-derived hIAPP in the pathogenesis of AD. Nevertheless, oxidative stress, mitochondrial dysfunction, chaperon-mediated autophagy, heparan sulfate proteoglycan (HSPG), immune response, and zinc homeostasis in T2DM could be the possible mechanisms for the induction of the aggregation of hIAPP which increase AD risk. In conclusion, increasing hIAPP circulating levels in T2DM patients predispose them to the development and progression of AD. Dipeptidyl peptidase 4 (DPP4) inhibitors and glucagon-like peptide-1 (GLP-1) agonists attenuate AD in T2DM by inhibiting expression and deposition of hIAP.
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Affiliation(s)
- Mohammed Alrouji
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Shaqra University, Shaqra, 11961, Saudi Arabia
| | - Hayder M Al-Kuraishy
- Department of clinical pharmacology and therapeutic medicine, college of medicine, ALmustansiriyiah University, M.B.Ch.B, FRCP, Baghdad, Box 14132, Iraq
| | - Ali I Al-Gareeb
- Department of clinical pharmacology and therapeutic medicine, college of medicine, ALmustansiriyiah University, M.B.Ch.B, FRCP, Baghdad, Box 14132, Iraq
| | - Athanasios Alexiou
- Department of Science and Engineering, Novel Global Community Educational Foundation, Hebersham, NSW, 2770, Australia
- AFNP Med, Wien, 1030, Austria
| | - Marios Papadakis
- Department of Surgery II, University Hospital Witten-Herdecke, Heusnerstrasse 40, 42283, Wuppertal, Germany.
| | - Hebatallah M Saad
- Department of Pathology, Faculty of Veterinary Medicine, Matrouh University, Marsa Matrouh, 51744, Egypt
| | - Gaber El-Saber Batiha
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, Damanhour, 22511, AlBeheira, Egypt
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Al-Turki TM, Griffith JD. Mammalian telomeric RNA (TERRA) can be translated to produce valine-arginine and glycine-leucine dipeptide repeat proteins. Proc Natl Acad Sci U S A 2023; 120:e2221529120. [PMID: 36812212 PMCID: PMC9992779 DOI: 10.1073/pnas.2221529120] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 01/25/2023] [Indexed: 02/24/2023] Open
Abstract
Mammalian telomeres consist of (TTAGGG)n repeats. Transcription of the C-rich strand generates a G-rich RNA, termed TERRA, containing G-quadruplex structures. Recent discoveries in several human nucleotide expansion diseases revealed that RNA transcripts containing long runs of 3 or 6 nt repeats which can form strong secondary structures can be translated in multiple frames to generate homopeptide or dipeptide repeat proteins, and multiple studies have shown them to be toxic in cells. We noted that the translation of TERRA would generate two dipeptide repeat proteins: highly charged repeating valine-arginine (VR)n and hydrophobic repeating glycine-leucine (GL)n. Here, we synthesized these two dipeptide proteins and raised polyclonal antibodies to VR. The VR dipeptide repeat protein binds nucleic acids and localizes strongly to replication forks in DNA. Both VR and GL form long 8-nm filaments with amyloid properties. Using labeled antibodies to VR and laser scanning confocal microscopy, threefold to fourfold more VR was observed in the nuclei of cell lines containing elevated TERRA as contrasted to a primary fibroblast line. Induction of telomere dysfunction via knockdown of TRF2 led to higher amounts of VR, and alteration of TERRA levels using a locked nucleic acid (LNA) GapmeR led to large nuclear VR aggregates. These observations suggest that telomeres, in particular in cells undergoing telomere dysfunction, may express two dipeptide repeat proteins with potentially strong biological properties.
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Affiliation(s)
- Taghreed M. Al-Turki
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC27599-7295
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC27599-7295
| | - Jack D. Griffith
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC27599-7295
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC27599-7295
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Castillo JJ, Aplin AC, Hackney DJ, Hogan MF, Esser N, Templin AT, Akter R, Kahn SE, Raleigh DP, Zraika S, Hull RL. Islet amyloid polypeptide aggregation exerts cytotoxic and proinflammatory effects on the islet vasculature in mice. Diabetologia 2022; 65:1687-1700. [PMID: 35871651 PMCID: PMC10208275 DOI: 10.1007/s00125-022-05756-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 04/28/2022] [Indexed: 01/29/2023]
Abstract
AIMS/HYPOTHESIS The islet vasculature, including its constituent islet endothelial cells, is a key contributor to the microenvironment necessary for normal beta cell health and function. In type 2 diabetes, islet amyloid polypeptide (IAPP) aggregates, forming amyloid deposits that accumulate between beta cells and islet capillaries. This process is known to be toxic to beta cells but its impact on the islet vasculature has not previously been studied. Here, we report the first characterisation of the effects of IAPP aggregation on islet endothelial cells/capillaries using cell-based and animal models. METHODS Primary and immortalised islet endothelial cells were treated with amyloidogenic human IAPP (hIAPP) alone or in the presence of the amyloid blocker Congo Red or the Toll-like receptor (TLR) 2/4 antagonist OxPAPc. Cell viability was determined0 along with mRNA and protein levels of inflammatory markers. Islet capillary abundance, morphology and pericyte coverage were determined in pancreases from transgenic mice with beta cell expression of hIAPP using conventional and confocal microscopy. RESULTS Aggregated hIAPP decreased endothelial cell viability in immortalised and primary islet endothelial cells (by 78% and 60%, respectively) and significantly increased expression of inflammatory markers Il6, Vcam1 and Edn1 mRNA relative to vehicle treatment in both cell types (p<0.05; n=4). Both cytotoxicity and the proinflammatory response were ameliorated by Congo Red (p<0.05; n=4); whereas TLR2/4-inhibition blocked inflammatory gene expression (p<0.05; n=6) without improving viability. Islets from high-fat-diet-fed amyloid-laden hIAPP transgenic mice also exhibited significantly increased expression of most markers of endothelial inflammation (p<0.05; n=5) along with decreased capillary density compared with non-transgenic littermates fed the same diet (p<0.01). Moreover, a 16% increase in capillary diameter was observed in amyloid-adjacent capillaries (p<0.01), accompanied by a doubling in pericyte structures positive for neuron-glial antigen 2 (p<0.001). CONCLUSIONS/INTERPRETATION Islet endothelial cells are susceptible to hIAPP-induced cytotoxicity and exhibit a TLR2/4-dependent proinflammatory response to aggregated hIAPP. Additionally, we observed amyloid-selective effects that decreased islet capillary density, accompanied by increased capillary diameter and increased pericyte number. Together, these data demonstrate that the islet vasculature is a target of the cytotoxic and proinflammatory effects of aggregated hIAPP that likely contribute to the detrimental effects of hIAPP aggregation on beta cell function and survival in type 2 diabetes.
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Affiliation(s)
- Joseph J Castillo
- Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, USA
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Alfred C Aplin
- Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, USA
| | - Daryl J Hackney
- Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, USA
| | - Meghan F Hogan
- Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, USA
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Nathalie Esser
- Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, USA
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Andrew T Templin
- Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, USA
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Rehana Akter
- Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, USA
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Steven E Kahn
- Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, USA
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Daniel P Raleigh
- Department of Chemistry, Stony Brook University, Stony Brook, NY, USA
- Research Department of Structural and Molecular Biology, University College London, London, UK
| | - Sakeneh Zraika
- Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, USA
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Rebecca L Hull
- Department of Veterans Affairs Puget Sound Health Care System, Seattle, WA, USA.
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington, Seattle, WA, USA.
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Marmentini C, Guimarães DSPSF, de Lima TI, Teófilo FBS, da Silva NS, Soares GM, Boschero AC, Kurauti MA. Rosiglitazone protects INS-1E cells from human islet amyloid polypeptide toxicity. Eur J Pharmacol 2022; 928:175122. [PMID: 35764131 DOI: 10.1016/j.ejphar.2022.175122] [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: 02/12/2022] [Revised: 06/21/2022] [Accepted: 06/22/2022] [Indexed: 11/18/2022]
Abstract
Human islet amyloid polypeptide (hIAPP or amylin) is a hormone co-secreted with insulin by pancreatic β-cells, and is the main component of islet amyloid. Islet amyloid is found in the pancreas of patients with type 2 diabetes and may be involved in β-cell dysfunction and death, observed in this disease. Thus, counteracting islet amyloid toxicity represents a therapeutic approach to preserve β-cell mass and function. In this sense, thiazolidinediones (TZDs), as rosiglitazone, have shown protective effects against other harmful insults to β-cells. For this reason, we investigated whether rosiglitazone could protect β-cells from hIAPP-induced cell death and the underlying mechanisms mediating such effect. Here, we show that rosiglitazone improved the viability of hIAPP-exposed INS-1E cells. This benefit is not dependent on the insulin-degrading enzyme (IDE) since rosiglitazone did not modulate IDE protein content and activity. However, rosiglitazone inhibited hIAPP fibrillation and decreased hIAPP-induced expression of C/EBP homologous protein (CHOP) (CTL 100.0 ± 8.4; hIAPP 182.7 ± 19.1; hIAPP + RGZ 102.8 ± 9.5), activating transcription factor-4 (ATF4) (CTL 100.0 ± 3.1; hIAPP 234.9 ± 19.3; hIAPP + RGZ 129.6 ± 3.0) and phospho-eukaryotic initiation factor 2-alpha (p-eIF2α) (CTL 100.0 ± 31.1; hIAPP 234.1 ± 36.2; hIAPP + RGZ 150.4 ± 18.0). These findings suggest that TZDs treatment may be a promising approach to preserve β-cell mass and function by inhibiting islet amyloid formation and decreasing endoplasmic reticulum stress hIAPP-induced.
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Affiliation(s)
- Carine Marmentini
- Laboratory of Endocrine Pancreas and Metabolism, Obesity and Comorbidities Research Center (OCRC), University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Dimitrius Santiago P S F Guimarães
- Laboratory of Endocrine Pancreas and Metabolism, Obesity and Comorbidities Research Center (OCRC), University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Tanes I de Lima
- Laboratory of Endocrine Pancreas and Metabolism, Obesity and Comorbidities Research Center (OCRC), University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Francisco Breno S Teófilo
- Electron Microscopy Laboratory, Institute of Biology, University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Natália S da Silva
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Gabriela M Soares
- Laboratory of Endocrine Pancreas and Metabolism, Obesity and Comorbidities Research Center (OCRC), University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Antonio C Boschero
- Laboratory of Endocrine Pancreas and Metabolism, Obesity and Comorbidities Research Center (OCRC), University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Mirian A Kurauti
- Department of Physiological Sciences, Biological Sciences Center, State University of Maringa (UEM), Maringa, Parana, Brazil.
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Roham PH, Save SN, Sharma S. Human islet amyloid polypeptide: A therapeutic target for the management of type 2 diabetes mellitus. J Pharm Anal 2022; 12:556-569. [PMID: 36105173 PMCID: PMC9463490 DOI: 10.1016/j.jpha.2022.04.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 03/21/2022] [Accepted: 04/01/2022] [Indexed: 12/22/2022] Open
Abstract
Type 2 diabetes mellitus (T2DM) and other metabolic disorders are often silent and go unnoticed in patients because of the lack of suitable prognostic and diagnostic markers. The current therapeutic regimens available for managing T2DM do not reverse diabetes; instead, they delay the progression of diabetes. Their efficacy (in principle) may be significantly improved if implemented at earlier stages. The misfolding and aggregation of human islet amyloid polypeptide (hIAPP) or amylin has been associated with a gradual decrease in pancreatic β-cell function and mass in patients with T2DM. Hence, hIAPP has been recognized as a therapeutic target for managing T2DM. This review summarizes hIAPP's role in mediating dysfunction and apoptosis in pancreatic β-cells via induction of endoplasmic reticulum stress, oxidative stress, mitochondrial dysfunction, inflammatory cytokine secretion, autophagy blockade, etc. Furthermore, it explores the possibility of using intermediates of the hIAPP aggregation pathway as potential drug targets for T2DM management. Finally, the effects of common antidiabetic molecules and repurposed drugs; other hIAPP mimetics and peptides; small organic molecules and natural compounds; nanoparticles, nanobodies, and quantum dots; metals and metal complexes; and chaperones that have demonstrated potential to inhibit and/or reverse hIAPP aggregation and can, therefore, be further developed for managing T2DM have been discussed. Misfolded species of hIAPP form toxic oligomers in pancreatic β-cells. hIAPP amyloids has been detected in the pancreas of about 90% subjects with T2DM. Inhibitors of hIAPP aggregation can help manage T2DM.
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Mukherjee N, Lin L, Contreras CJ, Templin AT. β-Cell Death in Diabetes: Past Discoveries, Present Understanding, and Potential Future Advances. Metabolites 2021; 11:796. [PMID: 34822454 PMCID: PMC8620854 DOI: 10.3390/metabo11110796] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 11/15/2021] [Accepted: 11/18/2021] [Indexed: 12/19/2022] Open
Abstract
β-cell death is regarded as a major event driving loss of insulin secretion and hyperglycemia in both type 1 and type 2 diabetes mellitus. In this review, we explore past, present, and potential future advances in our understanding of the mechanisms that promote β-cell death in diabetes, with a focus on the primary literature. We first review discoveries of insulin insufficiency, β-cell loss, and β-cell death in human diabetes. We discuss findings in humans and mouse models of diabetes related to autoimmune-associated β-cell loss and the roles of autoreactive T cells, B cells, and the β cell itself in this process. We review discoveries of the molecular mechanisms that underlie β-cell death-inducing stimuli, including proinflammatory cytokines, islet amyloid formation, ER stress, oxidative stress, glucotoxicity, and lipotoxicity. Finally, we explore recent perspectives on β-cell death in diabetes, including: (1) the role of the β cell in its own demise, (2) methods and terminology for identifying diverse mechanisms of β-cell death, and (3) whether non-canonical forms of β-cell death, such as regulated necrosis, contribute to islet inflammation and β-cell loss in diabetes. We believe new perspectives on the mechanisms of β-cell death in diabetes will provide a better understanding of this pathological process and may lead to new therapeutic strategies to protect β cells in the setting of diabetes.
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Affiliation(s)
- Noyonika Mukherjee
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA;
- Lilly Diabetes Center of Excellence, Indiana Biosciences Research Institute, Indianapolis, IN 46202, USA; (L.L.); (C.J.C.)
| | - Li Lin
- Lilly Diabetes Center of Excellence, Indiana Biosciences Research Institute, Indianapolis, IN 46202, USA; (L.L.); (C.J.C.)
| | - Christopher J. Contreras
- Lilly Diabetes Center of Excellence, Indiana Biosciences Research Institute, Indianapolis, IN 46202, USA; (L.L.); (C.J.C.)
- Department of Medicine, Roudebush Veterans Affairs Medical Center, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Andrew T. Templin
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA;
- Lilly Diabetes Center of Excellence, Indiana Biosciences Research Institute, Indianapolis, IN 46202, USA; (L.L.); (C.J.C.)
- Department of Medicine, Roudebush Veterans Affairs Medical Center, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Center for Diabetes and Metabolic Diseases, School of Medicine, Indiana University, Indianapolis, IN 46202, USA
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10
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Marmentini C, Branco RCS, Boschero AC, Kurauti MA. Islet amyloid toxicity: From genesis to counteracting mechanisms. J Cell Physiol 2021; 237:1119-1142. [PMID: 34636428 DOI: 10.1002/jcp.30600] [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: 03/21/2021] [Revised: 09/09/2021] [Accepted: 10/01/2021] [Indexed: 11/11/2022]
Abstract
Islet amyloid polypeptide (IAPP or amylin) is a hormone co-secreted with insulin by pancreatic β-cells and is the major component of islet amyloid. Islet amyloid is found in the pancreas of patients with type 2 diabetes (T2D) and may be involved in β-cell dysfunction and death, observed in this disease. Thus, investigating the aspects related to amyloid formation is relevant to the development of strategies towards β-cell protection. In this sense, IAPP misprocessing, IAPP overproduction, and disturbances in intra- and extracellular environments seem to be decisive for IAPP to form islet amyloid. Islet amyloid toxicity in β-cells may be triggered in intra- and/or extracellular sites by membrane damage, endoplasmic reticulum stress, autophagy disruption, mitochondrial dysfunction, inflammation, and apoptosis. Importantly, different approaches have been suggested to prevent islet amyloid cytotoxicity, from inhibition of IAPP aggregation to attenuation of cell death mechanisms. Such approaches have improved β-cell function and prevented the development of hyperglycemia in animals. Therefore, counteracting islet amyloid may be a promising therapy for T2D treatment.
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Affiliation(s)
- Carine Marmentini
- Laboratory of Endocrine Pancreas and Metabolism, Obesity and Comorbidities Research Center (OCRC), University of Campinas (UNICAMP), Campinas, Brazil
| | - Renato C S Branco
- Laboratory of Endocrine Pancreas and Metabolism, Obesity and Comorbidities Research Center (OCRC), University of Campinas (UNICAMP), Campinas, Brazil
| | - Antonio C Boschero
- Laboratory of Endocrine Pancreas and Metabolism, Obesity and Comorbidities Research Center (OCRC), University of Campinas (UNICAMP), Campinas, Brazil
| | - Mirian A Kurauti
- Laboratory of Endocrine Pancreas and Metabolism, Obesity and Comorbidities Research Center (OCRC), University of Campinas (UNICAMP), Campinas, Brazil.,Department of Physiological Sciences, Biological Sciences Center, State University of Maringa (UEM), Maringa, Brazil
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11
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Divalent Metal Transporter 1 Knock-Down Modulates IL-1β Mediated Pancreatic Beta-Cell Pro-Apoptotic Signaling Pathways through the Autophagic Machinery. Int J Mol Sci 2021; 22:ijms22158013. [PMID: 34360779 PMCID: PMC8348373 DOI: 10.3390/ijms22158013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/23/2021] [Accepted: 07/24/2021] [Indexed: 12/21/2022] Open
Abstract
Pro-inflammatory cytokines promote cellular iron-import through enhanced divalent metal transporter-1 (DMT1) expression in pancreatic β-cells, consequently cell death. Inhibition of β-cell iron-import by DMT1 silencing protects against apoptosis in animal models of diabetes. However, how alterations of signaling networks contribute to the protective action of DMT1 knock-down is unknown. Here, we performed phosphoproteomics using our sequential enrichment strategy of mRNA, protein, and phosphopeptides, which enabled us to explore the concurrent molecular events in the same set of wildtype and DMT1-silenced β-cells during IL-1β exposure. Our findings reveal new phosphosites in the IL-1β-induced proteins that are clearly reverted by DMT1 silencing towards their steady-state levels. We validated the levels of five novel phosphosites of the potential protective proteins using parallel reaction monitoring. We also confirmed the inactivation of autophagic flux that may be relevant for cell survival induced by DMT1 silencing during IL-1β exposure. Additionally, the potential protective proteins induced by DMT1 silencing were related to insulin secretion that may lead to improving β-cell functions upon exposure to IL-1β. This global profiling has shed light on the signal transduction pathways driving the protection against inflammation-induced cell death in β-cells after DMT1 silencing.
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12
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de Souza JG, Starobinas N, Ibañez OCM. Unknown/enigmatic functions of extracellular ASC. Immunology 2021; 163:377-388. [PMID: 34042182 DOI: 10.1111/imm.13375] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 04/23/2021] [Accepted: 05/11/2021] [Indexed: 12/18/2022] Open
Abstract
Apoptosis-associated speck-like protein containing a caspase recruit domain (ASC), encoded by PYCARD gene, is a 22 kDa small molecule, which aggregates into ASC specks during inflammasome activation. ASC protein is an adaptor protein present in several inflammasome complexes that performs several intra- and extracellular functions, in monomeric form or as ASC specks, during physiological and pathological processes related to inflammation and adaptive immunity. Extracellular ASC specks (eASC specks) released during cell death by pyroptosis can contribute as a danger signal to the propagation of inflammation via phagocytosis and activation of surrounding cells. ASC specks are found in the circulation of patients with chronic inflammatory diseases and have been considered as relevant blood biomarkers of inflammation. eASC amplifies the inflammatory signal, may induce the production of autoantibodies, transports molecules that bind to this complex, contributing to the generation of antibodies, and can induce the maturation of cytokines promoting the modelling of the adaptive immunity. Although several advances have been registered in the last 21 years, there are numerous unknown or enigmatic gaps in the understanding of the role of eASC specks in the organism. Here, we provide an overview about the ASC protein focusing on the probable roles of eASC specks in several diseases, up to the most recent studies concerning COVID-19.
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Affiliation(s)
- Jean Gabriel de Souza
- Laboratory of Immunogenetics, Butantan Institute, São Paulo, Brazil.,CENTD, Centre of Excellence in New Target Discovery, Butantan Institute, São Paulo, Brazil.,Immunology Catalyst, GlaxoSmithKline, Stevenag, UK
| | - Nancy Starobinas
- Laboratory of Immunogenetics, Butantan Institute, São Paulo, Brazil.,CENTD, Centre of Excellence in New Target Discovery, Butantan Institute, São Paulo, Brazil
| | - Olga Celia Martinez Ibañez
- Laboratory of Immunogenetics, Butantan Institute, São Paulo, Brazil.,CENTD, Centre of Excellence in New Target Discovery, Butantan Institute, São Paulo, Brazil
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13
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Benáková Š, Holendová B, Plecitá-Hlavatá L. Redox Homeostasis in Pancreatic β-Cells: From Development to Failure. Antioxidants (Basel) 2021; 10:antiox10040526. [PMID: 33801681 PMCID: PMC8065646 DOI: 10.3390/antiox10040526] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 03/23/2021] [Accepted: 03/25/2021] [Indexed: 12/16/2022] Open
Abstract
Redox status is a key determinant in the fate of β-cell. These cells are not primarily detoxifying and thus do not possess extensive antioxidant defense machinery. However, they show a wide range of redox regulating proteins, such as peroxiredoxins, thioredoxins or thioredoxin reductases, etc., being functionally compartmentalized within the cells. They keep fragile redox homeostasis and serve as messengers and amplifiers of redox signaling. β-cells require proper redox signaling already in cell ontogenesis during the development of mature β-cells from their progenitors. We bring details about redox-regulated signaling pathways and transcription factors being essential for proper differentiation and maturation of functional β-cells and their proliferation and insulin expression/maturation. We briefly highlight the targets of redox signaling in the insulin secretory pathway and focus more on possible targets of extracellular redox signaling through secreted thioredoxin1 and thioredoxin reductase1. Tuned redox homeostasis can switch upon chronic pathological insults towards the dysfunction of β-cells and to glucose intolerance. These are characteristics of type 2 diabetes, which is often linked to chronic nutritional overload being nowadays a pandemic feature of lifestyle. Overcharged β-cell metabolism causes pressure on proteostasis in the endoplasmic reticulum, mainly due to increased demand on insulin synthesis, which establishes unfolded protein response and insulin misfolding along with excessive hydrogen peroxide production. This together with redox dysbalance in cytoplasm and mitochondria due to enhanced nutritional pressure impact β-cell redox homeostasis and establish prooxidative metabolism. This can further affect β-cell communication in pancreatic islets through gap junctions. In parallel, peripheral tissues losing insulin sensitivity and overall impairment of glucose tolerance and gut microbiota establish local proinflammatory signaling and later systemic metainflammation, i.e., low chronic inflammation prooxidative properties, which target β-cells leading to their dedifferentiation, dysfunction and eventually cell death.
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Affiliation(s)
- Štěpánka Benáková
- Department of Mitochondrial Physiology, Institute of Physiology, Czech Academy of Sciences, 142 20 Prague 4, Czech Republic; (Š.B.); (B.H.)
- First Faculty of Medicine, Charles University, Katerinska 1660/32, 121 08 Prague, Czech Republic
| | - Blanka Holendová
- Department of Mitochondrial Physiology, Institute of Physiology, Czech Academy of Sciences, 142 20 Prague 4, Czech Republic; (Š.B.); (B.H.)
| | - Lydie Plecitá-Hlavatá
- Department of Mitochondrial Physiology, Institute of Physiology, Czech Academy of Sciences, 142 20 Prague 4, Czech Republic; (Š.B.); (B.H.)
- Department of Mitochondrial Physiology, Czech Academy of Sciences, Videnska 1083, 142 20 Prague 4, Czech Republic
- Correspondence: ; Tel.: +420-296-442-285
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14
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Denroche HC, Miard S, Sallé-Lefort S, Picard F, Verchere CB. T cells accumulate in non-diabetic islets during ageing. IMMUNITY & AGEING 2021; 18:8. [PMID: 33622333 PMCID: PMC7901217 DOI: 10.1186/s12979-021-00221-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Accepted: 02/11/2021] [Indexed: 12/25/2022]
Abstract
Background The resident immune population of pancreatic islets has roles in islet development, beta cell physiology, and the pathology of diabetes. These roles have largely been attributed to islet macrophages, comprising 90% of islet immune cells (in the absence of islet autoimmunity), and, in the case of type 1 diabetes, to infiltrating autoreactive T cells. In adipose, tissue-resident and recruited T and B cells have been implicated in the development of insulin resistance during diet-induced obesity and ageing, but whether this is paralleled in the pancreatic islets is not known. Here, we investigated the non-macrophage component of resident islet immune cells in islets isolated from C57BL/6 J male mice during ageing (3 to 24 months of age) and following similar weight gain achieved by 12 weeks of 60% high fat diet. Immune cells were also examined by flow cytometry in cadaveric non-diabetic human islets. Results Immune cells comprised 2.7 ± 1.3% of total islet cells in non-diabetic mouse islets, and 2.3 ± 1.7% of total islet cells in non-diabetic human islets. In 3-month old mice on standard diet, B and T cells each comprised approximately 2–4% of the total islet immune cell compartment, and approximately 0.1% of total islet cells. A similar amount of T cells were present in non-diabetic human islets. The majority of islet T cells expressed the αβ T cell receptor, and were comprised of CD8-positive, CD4-positive, and regulatory T cells, with a minor population of γδ T cells. Interestingly, the number of islet T cells increased linearly (R2 = 0.9902) with age from 0.10 ± 0.05% (3 months) to 0.38 ± 0.11% (24 months) of islet cells. This increase was uncoupled from body weight, and was not phenocopied by a degree similar weight gain induced by high fat diet in mice. Conclusions This study reveals that T cells are a part of the normal islet immune population in mouse and human islets, and accumulate in islets during ageing in a body weight-independent manner. Though comprising only a small subset of the immune cells within islets, islet T cells may play a role in the physiology of islet ageing. Supplementary Information The online version contains supplementary material available at 10.1186/s12979-021-00221-4.
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Affiliation(s)
- Heather C Denroche
- Canucks for Kids Fund Childhood Diabetes Laboratories, BC Children's Hospital Research Institute, Department of Surgery, University of British Columbia, Vancouver, British Columbia, Canada
| | - Stéphanie Miard
- Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, Québec, Canada
| | | | - Frédéric Picard
- Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, Québec, Canada.,Faculté de pharmacie, Université Laval, Québec, Québec, Canada
| | - C Bruce Verchere
- Canucks for Kids Fund Childhood Diabetes Laboratories, BC Children's Hospital Research Institute, Department of Surgery, University of British Columbia, Vancouver, British Columbia, Canada. .,Departments of Surgery and Pathology & Laboratory Medicine, BC Children's Hospital Research Institute, Centre for Molecular Medicine and Therapeutics, University of British Columbia, 950 West 28th Ave, Vancouver, British Columbia, V5Z 4H4, Canada.
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15
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Lundqvist M, Rodriguez Camargo DC, Bernfur K, Chia S, Linse S. Expression, purification and characterisation of large quantities of recombinant human IAPP for mechanistic studies. Biophys Chem 2021; 269:106511. [PMID: 33360112 DOI: 10.1016/j.bpc.2020.106511] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 11/22/2020] [Accepted: 11/23/2020] [Indexed: 01/09/2023]
Abstract
Malfunction and amyloid formation of the Islet Amyloid Polypeptide (IAPP) are factors contributing to Type 2 diabetes. Unravelling the mechanism of IAPP aggregate formation may forward our understanding of this process and its effect on pancreatic β-islet cell. Such mechanistic studies require access to sequence homogeneous and highly pure IAPP. Here we present a new facile protocol for the production of pure recombinant human IAPP at relatively high yield. The protocol uses a His-tagged version of the Npro mutant EDDIE, which drives expression to inclusion bodies, from which the peptide is purified using sonication, refolding and auto-cleavage, removal of EDDIE using Ni-NTA chromatography and reverse-phase HPLC. The purified material is used at multiple concentrations in aggregation kinetics measurements monitored by thioflavin-T fluorescence. Global analysis of the data implies a double nucleation aggregation mechanism including both primary and secondary nucleation.
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Affiliation(s)
- Martin Lundqvist
- Department of Biophysical, Chemistry, Chemical Centre, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
| | - Diana C Rodriguez Camargo
- Department of Biophysical, Chemistry, Chemical Centre, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden; Wren Therapeutics Limited, UK
| | - Katja Bernfur
- Department of Biophysical, Chemistry, Chemical Centre, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
| | | | - Sara Linse
- Department of Biophysical, Chemistry, Chemical Centre, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden; Wren Therapeutics Limited, UK.
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16
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Al-Halifa S, Zottig X, Babych M, Côté-Cyr M, Bourgault S, Archambault D. Harnessing the Activation of Toll-Like Receptor 2/6 by Self-Assembled Cross-β Fibrils to Design Adjuvanted Nanovaccines. NANOMATERIALS 2020; 10:nano10101981. [PMID: 33036404 PMCID: PMC7600500 DOI: 10.3390/nano10101981] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 10/03/2020] [Accepted: 10/04/2020] [Indexed: 12/30/2022]
Abstract
Protein fibrils characterized with a cross-β-sheet quaternary structure have gained interest as nanomaterials in biomedicine, including in the design of subunit vaccines. Recent studies have shown that by conjugating an antigenic determinant to a self-assembling β-peptide, the resulting supramolecular assemblies act as an antigen delivery system that potentiates the epitope-specific immune response. In this study, we used a ten-mer self-assembling sequence (I10) derived from an amyloidogenic peptide to biophysically and immunologically characterize a nanofibril-based vaccine against the influenza virus. The highly conserved epitope from the ectodomain of the matrix protein 2 (M2e) was elongated at the N-terminus of I10 by solid phase peptide synthesis. The chimeric M2e-I10 peptide readily self-assembled into unbranched, long, and twisted fibrils with a diameter between five and eight nm. These cross-β nanoassemblies were cytocompatible and activated the heterodimeric Toll-like receptor (TLR) 2/6. Upon mice subcutaneous immunization, M2e-fibrils triggered a robust anti-M2e specific immune response, which was dependent on self-assembly and did not require the use of an adjuvant. Overall, this study describes the efficacy of cross-β fibrils to activate the TLR 2/6 and to stimulate the epitope-specific immune response, supporting usage of these proteinaceous assemblies as a self-adjuvanted delivery system for antigens.
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Affiliation(s)
- Soultan Al-Halifa
- Department of Chemistry, Université du Québec à Montréal, Montreal, QC H2L 2C4, Canada; (S.A.-H.); (X.Z.); (M.B.); (M.C.-C)
- The Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Quebec, QC G1V 0A6, Canada
- The Swine and Poultry Infectious Diseases Research Centre, CRIPA, Saint-Hyacinthe, QC J2S 2M2, Canada
- Department of Biological Sciences, Université du Québec à Montréal, Montreal, QC H2L 2C4, Canada
| | - Ximena Zottig
- Department of Chemistry, Université du Québec à Montréal, Montreal, QC H2L 2C4, Canada; (S.A.-H.); (X.Z.); (M.B.); (M.C.-C)
- The Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Quebec, QC G1V 0A6, Canada
- The Swine and Poultry Infectious Diseases Research Centre, CRIPA, Saint-Hyacinthe, QC J2S 2M2, Canada
- Department of Biological Sciences, Université du Québec à Montréal, Montreal, QC H2L 2C4, Canada
| | - Margaryta Babych
- Department of Chemistry, Université du Québec à Montréal, Montreal, QC H2L 2C4, Canada; (S.A.-H.); (X.Z.); (M.B.); (M.C.-C)
- The Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Quebec, QC G1V 0A6, Canada
| | - Mélanie Côté-Cyr
- Department of Chemistry, Université du Québec à Montréal, Montreal, QC H2L 2C4, Canada; (S.A.-H.); (X.Z.); (M.B.); (M.C.-C)
- The Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Quebec, QC G1V 0A6, Canada
- The Swine and Poultry Infectious Diseases Research Centre, CRIPA, Saint-Hyacinthe, QC J2S 2M2, Canada
- Department of Biological Sciences, Université du Québec à Montréal, Montreal, QC H2L 2C4, Canada
| | - Steve Bourgault
- Department of Chemistry, Université du Québec à Montréal, Montreal, QC H2L 2C4, Canada; (S.A.-H.); (X.Z.); (M.B.); (M.C.-C)
- The Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Quebec, QC G1V 0A6, Canada
- The Swine and Poultry Infectious Diseases Research Centre, CRIPA, Saint-Hyacinthe, QC J2S 2M2, Canada
- Correspondence: (S.B.); (D.A.)
| | - Denis Archambault
- The Swine and Poultry Infectious Diseases Research Centre, CRIPA, Saint-Hyacinthe, QC J2S 2M2, Canada
- Department of Biological Sciences, Université du Québec à Montréal, Montreal, QC H2L 2C4, Canada
- Correspondence: (S.B.); (D.A.)
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17
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Guo J, Fu W. Immune regulation of islet homeostasis and adaptation. J Mol Cell Biol 2020; 12:764-774. [PMID: 32236479 PMCID: PMC7816675 DOI: 10.1093/jmcb/mjaa009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 01/08/2020] [Accepted: 01/13/2020] [Indexed: 02/06/2023] Open
Abstract
The islet of Langerhans produces endocrine hormones to regulate glucose homeostasis. The normal function of the islet relies on the homeostatic regulations of cellular composition and cell–cell interactions within the islet microenvironment. Immune cells populate the islet during embryonic development and participate in islet organogenesis and function. In obesity, a low-grade inflammation manifests in multiple organs, including pancreatic islets. Obesity-associated islet inflammation is evident in both animal models and humans, characterized by the accumulation of immune cells and elevated production of inflammatory cytokines/chemokines and metabolic mediators. Myeloid lineage cells (monocytes and macrophages) are the dominant types of immune cells in islet inflammation during the development of obesity and type 2 diabetes mellitus (T2DM). In this review, we will discuss the role of the immune system in islet homeostasis and inflammation and summarize recent findings of the cellular and molecular factors that alter islet microenvironment and β cell function in obesity and T2DM.
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Affiliation(s)
- Jinglong Guo
- Department of Pediatrics, Pediatric Diabetes Research Center, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Wenxian Fu
- Department of Pediatrics, Pediatric Diabetes Research Center, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
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18
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Balasubramanyam M. Does COVID-19 Warn Us to Revisit Virus-Induced Diabetes? EXPLORATORY RESEARCH AND HYPOTHESIS IN MEDICINE 2020; 000:1-5. [DOI: 10.14218/erhm.2020.00046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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19
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Zottig X, Côté-Cyr M, Arpin D, Archambault D, Bourgault S. Protein Supramolecular Structures: From Self-Assembly to Nanovaccine Design. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:E1008. [PMID: 32466176 PMCID: PMC7281494 DOI: 10.3390/nano10051008] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 05/18/2020] [Accepted: 05/20/2020] [Indexed: 12/19/2022]
Abstract
Life-inspired protein supramolecular assemblies have recently attracted considerable attention for the development of next-generation vaccines to fight against infectious diseases, as well as autoimmune diseases and cancer. Protein self-assembly enables atomic scale precision over the final architecture, with a remarkable diversity of structures and functionalities. Self-assembling protein nanovaccines are associated with numerous advantages, including biocompatibility, stability, molecular specificity and multivalency. Owing to their nanoscale size, proteinaceous nature, symmetrical organization and repetitive antigen display, protein assemblies closely mimic most invading pathogens, serving as danger signals for the immune system. Elucidating how the structural and physicochemical properties of the assemblies modulate the potency and the polarization of the immune responses is critical for bottom-up design of vaccines. In this context, this review briefly covers the fundamentals of supramolecular interactions involved in protein self-assembly and presents the strategies to design and functionalize these assemblies. Examples of advanced nanovaccines are presented, and properties of protein supramolecular structures enabling modulation of the immune responses are discussed. Combining the understanding of the self-assembly process at the molecular level with knowledge regarding the activation of the innate and adaptive immune responses will support the design of safe and effective nanovaccines.
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Affiliation(s)
- Ximena Zottig
- Department of Chemistry, Université du Québec à Montréal, Montreal, QC H2L 2C4, Canada; (X.Z.); (M.C.-C.); (D.A.)
- The Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Quebec, QC G1V 0A6, Canada
- The Swine and Poultry Infectious Diseases Research Centre, CRIPA, Saint-Hyacinthe, QC J2S 2M2, Canada
| | - Mélanie Côté-Cyr
- Department of Chemistry, Université du Québec à Montréal, Montreal, QC H2L 2C4, Canada; (X.Z.); (M.C.-C.); (D.A.)
- The Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Quebec, QC G1V 0A6, Canada
- The Swine and Poultry Infectious Diseases Research Centre, CRIPA, Saint-Hyacinthe, QC J2S 2M2, Canada
| | - Dominic Arpin
- Department of Chemistry, Université du Québec à Montréal, Montreal, QC H2L 2C4, Canada; (X.Z.); (M.C.-C.); (D.A.)
- The Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Quebec, QC G1V 0A6, Canada
- The Swine and Poultry Infectious Diseases Research Centre, CRIPA, Saint-Hyacinthe, QC J2S 2M2, Canada
| | - Denis Archambault
- The Swine and Poultry Infectious Diseases Research Centre, CRIPA, Saint-Hyacinthe, QC J2S 2M2, Canada
- Department of Biological Sciences, Université du Québec à Montréal, Montreal, QC H2L 2C4, Canada
| | - Steve Bourgault
- Department of Chemistry, Université du Québec à Montréal, Montreal, QC H2L 2C4, Canada; (X.Z.); (M.C.-C.); (D.A.)
- The Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Quebec, QC G1V 0A6, Canada
- The Swine and Poultry Infectious Diseases Research Centre, CRIPA, Saint-Hyacinthe, QC J2S 2M2, Canada
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20
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Ying W, Fu W, Lee YS, Olefsky JM. The role of macrophages in obesity-associated islet inflammation and β-cell abnormalities. Nat Rev Endocrinol 2020; 16:81-90. [PMID: 31836875 PMCID: PMC8315273 DOI: 10.1038/s41574-019-0286-3] [Citation(s) in RCA: 206] [Impact Index Per Article: 51.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/24/2019] [Indexed: 12/16/2022]
Abstract
Chronic, unresolved tissue inflammation is a well-described feature of obesity, type 2 diabetes mellitus (T2DM) and other insulin-resistant states. In this context, adipose tissue and liver inflammation have been particularly well studied; however, abundant evidence demonstrates that inflammatory processes are also activated in pancreatic islets from obese animals and humans with obesity and/or T2DM. In this Review, we focus on the characteristics of immune cell-mediated inflammation in islets and the consequences of this with respect to β-cell function. In contrast to type 1 diabetes mellitus, the dominant immune cell type causing inflammation in obese and T2DM islets is the macrophage. The increased macrophage accumulation in T2DM islets primarily arises through local proliferation of resident macrophages, which then provide signals (such as platelet-derived growth factor) that drive β-cell hyperplasia (a classic feature of obesity). In addition, islet macrophages also impair the insulin secretory capacity of β-cells. Through these mechanisms, islet-resident macrophages underlie the inflammatory response in obesity and mechanistically participate in the β-cell hyperplasia and dysfunction that characterizes this insulin-resistant state. These findings point to the possibility of therapeutics that target islet inflammation to elicit beneficial effects on β-cell function and glycaemia.
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Affiliation(s)
- Wei Ying
- Division of Endocrinology and Metabolism, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Wenxian Fu
- Pediatric Diabetes Research Center, Department of Pediatrics, University of California San Diego, La Jolla, CA, USA
| | - Yun Sok Lee
- Division of Endocrinology and Metabolism, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Jerrold M Olefsky
- Division of Endocrinology and Metabolism, Department of Medicine, University of California San Diego, La Jolla, CA, USA.
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21
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Huang YM, Hong XZ, Shen J, Geng LJ, Pan YH, Ling W, Zhao HL. Amyloids in Site-Specific Autoimmune Reactions and Inflammatory Responses. Front Immunol 2020; 10:2980. [PMID: 31993048 PMCID: PMC6964640 DOI: 10.3389/fimmu.2019.02980] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 12/04/2019] [Indexed: 12/15/2022] Open
Abstract
Amyloid deposition is a histological hallmark of common human disorders including Alzheimer's disease (AD) and type 2 diabetes. Although some reports highlight that amyloid fibrils might activate the innate immunity system via pattern recognition receptors, here, we provide multiple lines of evidence for the protection by site-specific amyloid protein analogs and fibrils against autoimmune attacks: (1) strategies targeting clearance of the AD-related brain amyloid plaque induce high risk of deadly autoimmune destructions in subjects with cognitive dysfunction; (2) administration of amyloidogenic peptides with either full length or core hexapeptide structure consistently ameliorates signs of experimental autoimmune encephalomyelitis; (3) experimental autoimmune encephalomyelitis is exacerbated following genetic deletion of amyloid precursor proteins; (4) absence of islet amyloid coexists with T-cell-mediated insulitis in autoimmune diabetes and autoimmune polyendocrine syndrome; (5) use of islet amyloid polypeptide agonists rather than antagonists improves diabetes care; and (6) common suppressive signaling pathways by regulatory T cells are activated in both local and systemic amyloidosis. These findings indicate dual modulation activity mediated by amyloid protein monomers, oligomers, and fibrils to maintain immune homeostasis. The protection from autoimmune destruction by amyloid proteins offers a novel therapeutic approach to regenerative medicine for common degenerative diseases.
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Affiliation(s)
- Yan-Mei Huang
- Department of Immunology, Guangxi Area of Excellence, Guilin Medical University, Guilin, China.,Center for Systems Medicine, Guangxi Key Laboratory of Excellence, Guilin Medical University, Guilin, China
| | - Xue-Zhi Hong
- Department of Immunology, Guangxi Area of Excellence, Guilin Medical University, Guilin, China.,Department of Rheumatology and Immunology, The First Affiliated Hospital of Guilin Medical University, Guilin, China
| | - Jian Shen
- Department of Immunology, Guangxi Area of Excellence, Guilin Medical University, Guilin, China.,Department of Pathology, The First Affiliated Hospital of Guilin Medical University, Guilin, China
| | - Li-Jun Geng
- Department of Immunology, Guangxi Area of Excellence, Guilin Medical University, Guilin, China.,Center for Systems Medicine, Guangxi Key Laboratory of Excellence, Guilin Medical University, Guilin, China
| | - Yan-Hong Pan
- Department of Immunology, Guangxi Area of Excellence, Guilin Medical University, Guilin, China.,Center for Systems Medicine, Guangxi Key Laboratory of Excellence, Guilin Medical University, Guilin, China
| | - Wei Ling
- Department of Immunology, Guangxi Area of Excellence, Guilin Medical University, Guilin, China.,Department of Endocrinology, Xiangya Medical School, Central South University, Changsha, China
| | - Hai-Lu Zhao
- Department of Immunology, Guangxi Area of Excellence, Guilin Medical University, Guilin, China.,Center for Systems Medicine, Guangxi Key Laboratory of Excellence, Guilin Medical University, Guilin, China.,Institute of Basic Medical Sciences, Faculty of Basic Medicine, Guilin Medical University, Guilin, China
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22
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Nackiewicz D, Dan M, Speck M, Chow SZ, Chen YC, Pospisilik JA, Verchere CB, Ehses JA. Islet Macrophages Shift to a Reparative State following Pancreatic Beta-Cell Death and Are a Major Source of Islet Insulin-like Growth Factor-1. iScience 2019; 23:100775. [PMID: 31962237 PMCID: PMC6971395 DOI: 10.1016/j.isci.2019.100775] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 09/24/2019] [Accepted: 12/10/2019] [Indexed: 12/21/2022] Open
Abstract
Macrophages play a dynamic role in tissue repair following injury. Here we found that following streptozotocin (STZ)-induced beta-cell death, mouse islet macrophages had increased Igf1 expression, decreased proinflammatory cytokine expression, and transcriptome changes consistent with macrophages undergoing efferocytosis and having an enhanced state of metabolism. Macrophages were the major, if not sole, contributors to islet insulin-like growth factor-1 (IGF-1) production. Adoptive transfer experiments showed that macrophages can maintain insulin secretion in vivo following beta-cell death with no effects on islet cell turnover. IGF-1 neutralization during STZ treatment decreased insulin secretion without affecting islet cell apoptosis or proliferation. Interestingly, high-fat diet (HFD) combined with STZ further skewed islet macrophages to a reparative state. Finally, islet macrophages from db/db mice also expressed decreased proinflammatory cytokines and increased Igf1 mRNA. These data have important implications for islet biology and pathology and show that islet macrophages preserve their reparative state following beta-cell death even during HFD feeding and severe hyperglycemia. Macrophages are a major source of IGF-1 protein within mouse pancreatic islets Post-beta-cell death islet macrophages shift to a reparative state Beta-cell death causes macrophage transcriptome changes consistent with efferocytosis This change can occur even in the presence of HFD feeding or severe hyperglycemia
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Affiliation(s)
- Dominika Nackiewicz
- Department of Surgery, Faculty of Medicine, University of British Columbia, BC Children's Hospital Research Institute, 950 W 28 Avenue, Vancouver V5Z 4H4, Canada
| | - Meixia Dan
- Department of Surgery, Faculty of Medicine, University of British Columbia, BC Children's Hospital Research Institute, 950 W 28 Avenue, Vancouver V5Z 4H4, Canada
| | - Madeleine Speck
- Department of Surgery, Faculty of Medicine, University of British Columbia, BC Children's Hospital Research Institute, 950 W 28 Avenue, Vancouver V5Z 4H4, Canada
| | - Samuel Z Chow
- Department of Surgery, Faculty of Medicine, University of British Columbia, BC Children's Hospital Research Institute, 950 W 28 Avenue, Vancouver V5Z 4H4, Canada
| | - Yi-Chun Chen
- Department of Surgery, Faculty of Medicine, University of British Columbia, BC Children's Hospital Research Institute, 950 W 28 Avenue, Vancouver V5Z 4H4, Canada
| | - J Andrew Pospisilik
- Van Andel Research Institute, 333 Bostwick Avenue NE, Grand Rapids, MI 49503, USA
| | - C Bruce Verchere
- Department of Surgery, Faculty of Medicine, University of British Columbia, BC Children's Hospital Research Institute, 950 W 28 Avenue, Vancouver V5Z 4H4, Canada; Department of Pathology and Laboratory Medicine, BC Children's Hospital Research Institute, 950 W 28 Avenue, Vancouver V5Z 4H4, Canada.
| | - Jan A Ehses
- Department of Surgery, Faculty of Medicine, University of British Columbia, BC Children's Hospital Research Institute, 950 W 28 Avenue, Vancouver V5Z 4H4, Canada; Department of Health Sciences and Technology, Institute of Food, Nutrition, and Health, Swiss Federal Institute of Technology, ETH Zürich, Schwerzenbach CH-8603, Switzerland.
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23
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The novel small-molecule antagonist MMG-11 preferentially inhibits TLR2/1 signaling. Biochem Pharmacol 2019; 171:113687. [PMID: 31678495 DOI: 10.1016/j.bcp.2019.113687] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 10/29/2019] [Indexed: 12/15/2022]
Abstract
Toll-like receptor 2 (TLR2) forms heterodimers with either TLR1 or TLR6 to induce protective early inflammatory responses to pathogen- and damage-associated molecular patterns. However, excessive activation is associated with inflammatory and metabolic diseases. Several TLR2 antagonists have been described but pharmacological characterization is still at an early stage. Previously, we identified the potent and selective TLR2 antagonist MMG-11 by computational modelling and experimental validation. Here, we characterized the TLR2 antagonists MMG-11 and CU-CPT22 as well as the TIR-domain binding TLR2 antagonist C29 in TLR-overexpressing promoter cells as well as human and mouse macrophages. In line with our recent studies, MMG-11 abrogated pro-inflammatory cytokine secretion and NF-κB activation induced by different bacterial TLR2 agonists. MMG-11 preferentially inhibited TLR2/1 signaling in promoter cells stably expressing TLR2 heterodimers and mouse macrophages. Furthermore, the TLR2 antagonist blocked ligand-induced interaction of TLR2 with MyD88 and reduced MAP kinase and NF-κB activation. MMG-11 and CU-CPT22 but not C29 displaced Pam3CSK4 in an indirect binding assay confirming the competitive mode of action of MMG-11 and CU-CPT22. Isobologram analysis revealed additive and synergistic effects when the non-competitive antagonist C29 was combined with the competitive antagonist MMG-11 or CU-CPT22, respectively. In conclusion, we provide evidence that MMG-11 acts as a competitive antagonist with a predominance for the TLR2/1 heterodimer in human and mouse cells. Our results also indicate that MMG-11 is a model compound for studying TLR2 signaling.
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24
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Modulation of Innate Immunity by Amyloidogenic Peptides. Trends Immunol 2019; 40:762-780. [PMID: 31320280 DOI: 10.1016/j.it.2019.06.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 06/11/2019] [Accepted: 06/12/2019] [Indexed: 12/11/2022]
Abstract
Amyloid formation contributes to the development of progressive metabolic and neurodegenerative diseases, while also serving functional roles in host defense. Emerging evidence suggests that as amyloidogenic peptides populate distinct aggregation states, they interact with different combinations of pattern recognition receptors (PRRs) to direct the phenotype and function of tissue-resident and infiltrating innate immune cells. We review recent evidence of innate immunomodulation by distinct forms of amyloidogenic peptides produced by mammals (humans, non-human primates), bacteria, and fungi, as well as the corresponding cell-surface and intracellular PRRs in these interactions, in human and mouse models. Our emerging understanding of peptide aggregate-innate immune cell interactions, and the factors regulating the balance between amyloid function and pathogenicity, might aid the development of anti-amyloid and immunomodulating therapies.
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25
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Böni-Schnetzler M, Meier DT. Islet inflammation in type 2 diabetes. Semin Immunopathol 2019; 41:501-513. [PMID: 30989320 PMCID: PMC6592966 DOI: 10.1007/s00281-019-00745-4] [Citation(s) in RCA: 111] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 03/29/2019] [Indexed: 12/16/2022]
Abstract
Metabolic diseases including type 2 diabetes are associated with meta-inflammation. β-Cell failure is a major component of the pathogenesis of type 2 diabetes. It is now well established that increased numbers of innate immune cells, cytokines, and chemokines have detrimental effects on islets in these chronic conditions. Recently, evidence emerged which points to initially adaptive and restorative functions of inflammatory factors and immune cells in metabolism. In the following review, we provide an overview on the features of islet inflammation in diabetes and models of prediabetes. We separately emphasize what is known on islet inflammation in humans and focus on in vivo animal models and how they are used to elucidate mechanistic aspects of islet inflammation. Further, we discuss the recently emerging physiologic signaling role of cytokines during adaptation and normal function of islet cells.
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Affiliation(s)
- Marianne Böni-Schnetzler
- Endocrinology, Diabetes and Metabolism, University Hospital of Basel, 4031, Basel, Switzerland. .,Department of Biomedicine, University Hospital and University of Basel, Hebelstrasse 20, 4031, Basel, Switzerland.
| | - Daniel T Meier
- Endocrinology, Diabetes and Metabolism, University Hospital of Basel, 4031, Basel, Switzerland.,Department of Biomedicine, University Hospital and University of Basel, Hebelstrasse 20, 4031, Basel, Switzerland
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26
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Javed I, He J, Kakinen A, Faridi A, Yang W, Davis TP, Ke PC, Chen P. Probing the Aggregation and Immune Response of Human Islet Amyloid Polypeptides with Ligand-Stabilized Gold Nanoparticles. ACS APPLIED MATERIALS & INTERFACES 2019; 11:10462-10471. [PMID: 30663303 DOI: 10.1021/acsami.8b19506] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The use of nanomaterials has recently become an emerging strategy against protein amyloidosis associated with a range of metabolic and brain diseases. To facilitate research in this area, here we first demonstrated the use of hyperspectral imaging (HSI) and COMSOL simulations for reporting the aggregation of human islet amyloid polypeptides (IAPPs), a hallmark of type 2 diabetes, as well as the physical interactions between the peptide and gold nanoparticles (AuNPs) grafted with citrate and poly(ethylene glycol) (PEG400 and PEG3000). We found a distinct anticorrelation between increased IAPP aggregation and decreased spectral red shifts incurred in the AuNP plasmonic resonance. Moreover, Jurkat cells exposed to IAPP and AuNPs were characterized by quantifying their cytokine secretions with a localized surface plasmon resonance (LSPR) immunoassay, where a peak response was registered for the most toxic IAPP oligomers and most suppressed by citrate-coated AuNPs. This study demonstrated the potential of using HSI and LSPR as two new platforms for the facile examination of protein aggregation and their induced immune response associated with amyloid diseases.
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Affiliation(s)
- Ibrahim Javed
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences , Monash University , 381 Royal Parade , Parkville , VIC 3052 , Australia
| | - Jiacheng He
- Materials Research and Education Center , Auburn University , Auburn , Alabama 36849 , United States
| | - Aleksandr Kakinen
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences , Monash University , 381 Royal Parade , Parkville , VIC 3052 , Australia
| | - Ava Faridi
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences , Monash University , 381 Royal Parade , Parkville , VIC 3052 , Australia
| | - Wen Yang
- Materials Research and Education Center , Auburn University , Auburn , Alabama 36849 , United States
| | - Thomas P Davis
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences , Monash University , 381 Royal Parade , Parkville , VIC 3052 , Australia
| | - Pu Chun Ke
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences , Monash University , 381 Royal Parade , Parkville , VIC 3052 , Australia
| | - Pengyu Chen
- Materials Research and Education Center , Auburn University , Auburn , Alabama 36849 , United States
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NLRP3 inflammasome activation in inflammaging. Semin Immunol 2018; 40:61-73. [PMID: 30268598 DOI: 10.1016/j.smim.2018.09.001] [Citation(s) in RCA: 106] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 09/17/2018] [Accepted: 09/18/2018] [Indexed: 02/06/2023]
Abstract
The process of aging is associated with the appearance of low-grade subclinical inflammation, termed inflammaging, that can accelerate age-related diseases. In Western societies the age-related inflammatory response can additionally be aggravated by an inflammatory response related to modern lifestyles and excess calorie consumption, a pathophysiologic inflammatory response that was coined metaflammation. Here, we summarize the current knowledge of mechanisms that drive both of these processes and focus our discussion the emerging concept that a key innate immune pathway, the NLRP3 inflammasome, is centrally involved in the recognition of triggers that appear during physiological aging and during metabolic stress. We further discuss how these processes are involved in the pathogenesis of common age-related pathologies and highlight potential strategies by which the detrimental inflammatory responses could be pharmacologically addressed.
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28
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Polumuri SK, Haile LA, Ireland DDC, Verthelyi D. Aggregates of IVIG or Avastin, but not HSA, modify the response to model innate immune response modulating impurities. Sci Rep 2018; 8:11477. [PMID: 30065306 PMCID: PMC6068171 DOI: 10.1038/s41598-018-29850-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 07/06/2018] [Indexed: 12/11/2022] Open
Abstract
Therapeutic proteins can induce immune responses that affect their safety and efficacy. Product aggregates and innate immune response modulating impurities (IIRMI) are risk factors of product immunogenicity. In this study, we use Intravenous Immunoglobulin (IVIG), Avastin, and Human Serum Albumin (HSA) to explore whether increased aggregates activate innate immune cells or modify the response to IIRMI. We show that increased aggregates (shaken or stirred) in IVIG and Avastin, but not HSA, induced activation of MAPKs (pp38, pERK and pJNK) and transcription of immune-related genes including IL8, IL6, IL1β, CSF1, CCL2, CCL7, CCL3, CCL24, CXCL2, IRAK1, EGR2, CEBPβ, PPARg and TNFSF15 in human PBMC. The immunomodulatory effect was primarily mediated by FcγR, but not by TLR. Interestingly, increased aggregates in IVIG or Avastin magnified innate immune responses to TLR2/4 agonists, but diminished responses to TLR3/9 agonists. This study shows that IIRMI and aggregates can modify the activity of immune cells potentially modifying the milieu where the products are delivered highlighting the complex interplay of different impurities on product immunogenicity risk. Further, we show that aggregates could modify the sensitivity of PBMC-based assays designed to detect IIRMI. Understanding and managing immunogenicity risk is a critical component of product development and regulation.
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Affiliation(s)
- Swamy Kumar Polumuri
- Division of Biotechnology Review and Research-III, Office of Biotechnology Products, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - Lydia A Haile
- Division of Biotechnology Review and Research-III, Office of Biotechnology Products, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - Derek D C Ireland
- Division of Biotechnology Review and Research-III, Office of Biotechnology Products, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, MD, 20993, USA
| | - Daniela Verthelyi
- Division of Biotechnology Review and Research-III, Office of Biotechnology Products, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, MD, 20993, USA.
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29
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Denroche HC, Verchere CB. IAPP and type 1 diabetes: implications for immunity, metabolism and islet transplants. J Mol Endocrinol 2018; 60:R57-R75. [PMID: 29378867 DOI: 10.1530/jme-17-0138] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 12/06/2017] [Indexed: 01/12/2023]
Abstract
Islet amyloid polypeptide (IAPP), the main component of islet amyloid in type 2 diabetes and islet transplants, is now recognized as a contributor to beta cell dysfunction. Increasingly, evidence warrants its investigation in type 1 diabetes owing to both its immunomodulatory and metabolic actions. Autoreactive T cells to IAPP-derived epitopes have been described in humans, suggesting that IAPP is an islet autoantigen in type 1 diabetes. In addition, although aggregates of IAPP have not been implicated in type 1 diabetes, they are potent pro-inflammatory stimuli to innate immune cells, and thus, could influence autoimmunity. IAPP aggregates also occur rapidly in transplanted islets and likely contribute to islet transplant failure in type 1 diabetes through sterile inflammation. In addition, since type 1 diabetes is a disease of both insulin and IAPP deficiency, clinical trials have examined the potential benefits of IAPP replacement in type 1 diabetes with the injectable IAPP analogue, pramlintide. Pramlintide limits postprandial hyperglycemia by delaying gastric emptying and suppressing hyperglucagonemia, underlining the possible role of IAPP in postprandial glucose metabolism. Here, we review IAPP in the context of type 1 diabetes: from its potential involvement in type 1 diabetes pathogenesis, through its role in glucose metabolism and use of IAPP analogues as therapeutics, to its potential role in clinical islet transplant failure and considerations in this regard for future beta cell replacement strategies.
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Affiliation(s)
- Heather C Denroche
- Department of Surgery, BC Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - C Bruce Verchere
- Department of Surgery, BC Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Pathology and Laboratory Medicine, BC Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
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30
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Lee YS, Wollam J, Olefsky JM. An Integrated View of Immunometabolism. Cell 2018; 172:22-40. [PMID: 29328913 PMCID: PMC8451723 DOI: 10.1016/j.cell.2017.12.025] [Citation(s) in RCA: 290] [Impact Index Per Article: 48.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 10/17/2017] [Accepted: 12/18/2017] [Indexed: 02/07/2023]
Abstract
The worldwide obesity epidemic has emerged as a major cause of insulin resistance and Type 2 diabetes. Chronic tissue inflammation is a well-recognized feature of obesity, and the field of immunometabolism has witnessed many advances in recent years. Here, we review the major features of our current understanding with respect to chronic obesity-related inflammation in metabolic tissues and focus on how these inflammatory changes affect insulin sensitivity, insulin secretion, food intake, and glucose homeostasis. There is a growing appreciation of the varied and sometimes integrated crosstalk between cells within a tissue (intraorgan) and tissues within an organism (interorgan) that supports inflammation in the context of metabolic dysregulation. Understanding these pathways and modes of communication has implications for translational studies. We also briefly summarize the state of this field with respect to potential current and developing therapeutics.
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Affiliation(s)
- Yun Sok Lee
- Department of Medicine, Division of Endocrinology and Metabolism, University of California, San Diego, La Jolla, CA 92093, USA; Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
| | - Joshua Wollam
- Department of Medicine, Division of Endocrinology and Metabolism, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jerrold M Olefsky
- Department of Medicine, Division of Endocrinology and Metabolism, University of California, San Diego, La Jolla, CA 92093, USA.
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31
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Endogenous DAMPs, Category I: Constitutively Expressed, Native Molecules (Cat. I DAMPs). DAMAGE-ASSOCIATED MOLECULAR PATTERNS IN HUMAN DISEASES 2018. [PMCID: PMC7122936 DOI: 10.1007/978-3-319-78655-1_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This chapter provides the reader with a collection of endogenous DAMPs in terms of constitutively expressed native molecules. The first class of this category refers to DAMPs, which are passively released from necrotic cells, and includes the most prominent subclasses of high mobility group box I and heat shock proteins. Further subclasses of DAMPs that are passively released from necrotic cells include S100 proteins, nucleic acids, histones, pro-forms of interleukin-1-family members, mitochondria-derived N-formylated peptides, F-actin, and heme. A particular subclass of these passively released DAMPs are molecules, which indirectly activate the inflammasome, including adenosine-5′-triphosphate, monosodium urate crystals, cholesterol crystals, some lipolytic species, and beta-amyloid. All these passively released DAMPs are characterized by their capability to promote necroinflammatory responses. The second class of this Category I refers to molecules, which are exposed on the surface of stressed cells. They include the subclass of phagocytosis-facilitating molecules such as calreticulin, as well as the subclass of MHC-I-related molecules such as MHC-I-related molecule A and B. These DAMPs are capable of inducing the activation of innate lymphoid cells and unconventional T cells. One of these DAMPs, the major histocompatibility complex I-related molecule A, is shown to act as a bona fide transplantation antigen. In sum, the endogenous constitutively expressed native molecules represent an impressive category of DAMPs with extraordinary properties, which play a critical role in the pathogenesis of many human diseases.
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32
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Zhang Y, Yu XL, Zhu J, Liu SY, Liu XM, Dong QX, Chai JQ, Liu RT. Intravenous immunoglobulin improves glucose control and β-cell function in human IAPP transgenic mice by attenuating islet inflammation and reducing IAPP oligomers. Int Immunopharmacol 2017; 54:145-152. [PMID: 29145032 DOI: 10.1016/j.intimp.2017.11.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/08/2017] [Accepted: 11/08/2017] [Indexed: 02/06/2023]
Abstract
Type 2 diabetes mellitus (T2DM) is a metabolic disorder characterized by β-cell loss, insulin resistance, islet inflammation and amyloid deposits derived from islet amyloid polypeptide (IAPP). Reducing toxic IAPP oligomers and inhibiting islet inflammation may provide therapeutic benefit in treating T2DM. Intravenous immunoglobulin (IVIg) is an efficient anti-inflammatory and immunomodulatory agent for the treatment of several autoimmune or inflammatory neurological diseases. However, whether IVIg has therapeutic potential on T2DM remains unclear. In present study, we showed that IVIg treatment significantly improved glucose control and insulin sensitivity, and prevented β-cell apoptosis by lowering toxic IAPP oligomer levels, attenuating islet inflammation and activating autophagy in human IAPP transgenic mouse model. These results suggest that IVIg is a promising therapeutic potential for T2DM treatment.
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Affiliation(s)
- Yue Zhang
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; Shandong Agricultural University, Taian, 271018, China
| | - Xiao-Lin Yu
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Jie Zhu
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Shu-Ying Liu
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Xiang-Meng Liu
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Quan-Xiu Dong
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Jia-Qian Chai
- Shandong Agricultural University, Taian, 271018, China.
| | - Rui-Tian Liu
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
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33
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Alcarraz-Vizán G, Castaño C, Visa M, Montane J, Servitja JM, Novials A. BACE2 suppression promotes β-cell survival and function in a model of type 2 diabetes induced by human islet amyloid polypeptide overexpression. Cell Mol Life Sci 2017; 74:2827-2838. [PMID: 28337562 PMCID: PMC11107557 DOI: 10.1007/s00018-017-2505-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 03/08/2017] [Accepted: 03/09/2017] [Indexed: 02/07/2023]
Abstract
BACE2 (β-site APP-cleaving enzyme 2) is a protease expressed in the brain, but also in the pancreas, where it seems to play a physiological role. Amyloidogenic diseases, including Alzheimer's disease and type 2 diabetes (T2D), share the accumulation of abnormally folded and insoluble proteins that interfere with cell function. In T2D, islet amyloid polypeptide (IAPP) deposits have been shown to be a pathogenic key feature of the disease. The aim of the present study was to investigate the effect of BACE2 modulation on β-cell alterations in a mouse model of T2D induced by IAPP overexpression. Heterozygous mice carrying the human transcript of IAPP (hIAPP-Tg) were used as a model to study the deleterious effects of IAPP upon β-cell function. These animals showed glucose intolerance and impaired insulin secretion. When crossed with BACE2-deficient mice, the animals presented a significant improvement in glucose tolerance accompanied with an enhanced insulin secretion, as compared to hIAPP-Tg mice. BACE2 deficiency also partially reverted gene expression changes observed in islets from hIAPP-Tg mice, including a set of genes related to inflammation. Moreover, homozygous hIAPP mice presented a severe hyperglycemia and a high lethality rate from 8 weeks onwards due to a massive destruction of β-cell mass. This process was significantly reduced when crossed with the BACE2-KO model, improving the survival rate of the animals. Altogether, the absence of BACE2 ameliorates glucose tolerance defects induced by IAPP overexpression in the β-cell and promotes β-cell survival. Thus, targeting BACE2 may represent a promising therapeutic strategy to improve β-cell function in T2D.
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Affiliation(s)
- Gema Alcarraz-Vizán
- Diabetes and Obesity Research Laboratory, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), C/Rosselló 149-153, 5th floor, 08036, Barcelona, Spain
| | - Carlos Castaño
- Diabetes and Obesity Research Laboratory, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), C/Rosselló 149-153, 5th floor, 08036, Barcelona, Spain
| | - Montse Visa
- Diabetes and Obesity Research Laboratory, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), C/Rosselló 149-153, 5th floor, 08036, Barcelona, Spain
| | - Joel Montane
- Diabetes and Obesity Research Laboratory, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), C/Rosselló 149-153, 5th floor, 08036, Barcelona, Spain
| | - Joan-Marc Servitja
- Diabetes and Obesity Research Laboratory, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), C/Rosselló 149-153, 5th floor, 08036, Barcelona, Spain.
| | - Anna Novials
- Diabetes and Obesity Research Laboratory, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERDEM), C/Rosselló 149-153, 5th floor, 08036, Barcelona, Spain.
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34
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Patel MN, Carroll RG, Galván-Peña S, Mills EL, Olden R, Triantafilou M, Wolf AI, Bryant CE, Triantafilou K, Masters SL. Inflammasome Priming in Sterile Inflammatory Disease. Trends Mol Med 2017; 23:165-180. [PMID: 28109721 DOI: 10.1016/j.molmed.2016.12.007] [Citation(s) in RCA: 184] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 12/15/2016] [Accepted: 12/16/2016] [Indexed: 02/08/2023]
Abstract
The inflammasome is a cytoplasmic protein complex that processes interleukins (IL)-1β and IL-18, and drives a form of cell death known as pyroptosis. Oligomerization of this complex is actually the second step of activation, and a priming step must occur first. This involves transcriptional upregulation of pro-IL-1β, inflammasome sensor NLRP3, or the non-canonical inflammasome sensor caspase-11. An additional aspect of priming is the post-translational modification of particular inflammasome constituents. Priming is typically accomplished in vitro using a microbial Toll-like receptor (TLR) ligand. However, it is now clear that inflammasomes are activated during the progression of sterile inflammatory diseases such as atherosclerosis, metabolic disease, and neuroinflammatory disorders. Therefore, it is time to consider the endogenous factors and mechanisms that may prime the inflammasome in these conditions.
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Affiliation(s)
- Meghana N Patel
- Immunology Catalyst, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK
| | - Richard G Carroll
- Immunology Catalyst, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK; School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Silvia Galván-Peña
- Immunology Catalyst, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK; School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Evanna L Mills
- Immunology Catalyst, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK; School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Robin Olden
- Immunology Catalyst, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK; Institute of Infection and Immunity, School of Medicine, University Hospital of Wales, Cardiff University, Cardiff, UK
| | - Martha Triantafilou
- Immunology Catalyst, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK; Institute of Infection and Immunity, School of Medicine, University Hospital of Wales, Cardiff University, Cardiff, UK
| | - Amaya I Wolf
- Host Defense Discovery Performance Unit, Infectious Diseases Therapeutic Area, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Clare E Bryant
- Immunology Catalyst, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK; Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB23 8AQ, UK
| | - Kathy Triantafilou
- Immunology Catalyst, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK; Institute of Infection and Immunity, School of Medicine, University Hospital of Wales, Cardiff University, Cardiff, UK
| | - Seth L Masters
- Immunology Catalyst, GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK; Department of Medical Biology, University of Melbourne, Parkville 3010, Australia; Inflammation Division, The Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia.
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Abstract
The finding of islet inflammation in type 2 diabetes (T2D) and its involvement in β cell dysfunction has further highlighted the significance of inflammation in metabolic diseases. The number of intra-islet macrophages is increased in T2D, and these cells are the main source of proinflammatory cytokines within islets. Multiple human studies of T2D have shown that targeting islet inflammation has the potential to be an effective therapeutic strategy. In this Review we provide an overview of the cellular and molecular mechanisms by which islet inflammation develops and causes β cell dysfunction. We also emphasize the regulation and roles of macrophage polarity shift within islets in the context of T2D pathology and β cell health, which may have broad translational implications for therapeutics aimed at improving islet function.
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Su Q, Grabowski M, Weindl G. Recognition of Propionibacterium acnes by human TLR2 heterodimers. Int J Med Microbiol 2016; 307:108-112. [PMID: 28024924 DOI: 10.1016/j.ijmm.2016.12.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 11/25/2016] [Accepted: 12/10/2016] [Indexed: 11/26/2022] Open
Abstract
Propionibacterium acnes has been considered as a crucial contributor to the pathogenesis of acne vulgaris. The interaction between P. acnes and the host is mainly mediated by Toll like receptor (TLR) 2 recognition. TLR2 homodimers recognize P. acnes in mice, but here we describe the prerequisite of TLR2/1 and TLR2/6 heterodimers in human cells for P. acnes recognition. P. acnes-induced NF-κB and AP-1activation observed in HEK hTLR2-transfected but not control cells confirmed the specificity of TLR2 recognition. The activation was blocked by neutralizing antibodies against TLR2, TLR1 and TLR6, as well as the TLR2 antagonist CU-CPT22, which showed no selectivity towards human TLR2 heterodimers. The combination of anti-TLR1 and anti-TLR6 antibodies completely abrogated activation by P. acnes. In primary human keratinocytes, P. acnes-increased NF-κB phosphorylation was inhibited by anti-TLR6 and anti-TLR2 antibodies. Furthermore, P. acnes-induced inflammatory responses were impaired by anti-TLR2 neutralizing antibodies and fully blocked by CU-CPT22. Our study suggests species-specific recognition of P. acnes by TLR2 heterodimers which can be exploited therapeutically by small molecules targeting TLR2 for the control of inflammatory responses.
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Affiliation(s)
- Qi Su
- Freie Universität Berlin, Institute of Pharmacy (Pharmacology and Toxicology), Berlin, Germany
| | - Maria Grabowski
- Freie Universität Berlin, Institute of Pharmacy (Pharmacology and Toxicology), Berlin, Germany
| | - Günther Weindl
- Freie Universität Berlin, Institute of Pharmacy (Pharmacology and Toxicology), Berlin, Germany.
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