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Scanlan A, Zhang Z, Koneru R, Reece M, Gavegnano C, Anderson AM, Tyor W. A Rationale and Approach to the Development of Specific Treatments for HIV Associated Neurocognitive Impairment. Microorganisms 2022; 10:2244. [PMID: 36422314 PMCID: PMC9699382 DOI: 10.3390/microorganisms10112244] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/03/2022] [Accepted: 11/08/2022] [Indexed: 05/22/2024] Open
Abstract
Neurocognitive impairment (NCI) associated with HIV infection of the brain impacts a large proportion of people with HIV (PWH) regardless of antiretroviral therapy (ART). While the number of PWH and severe NCI has dropped considerably with the introduction of ART, the sole use of ART is not sufficient to prevent or arrest NCI in many PWH. As the HIV field continues to investigate cure strategies, adjunctive therapies are greatly needed. HIV imaging, cerebrospinal fluid, and pathological studies point to the presence of continual inflammation, and the presence of HIV RNA, DNA, and proteins in the brain despite ART. Clinical trials exploring potential adjunctive therapeutics for the treatment of HIV NCI over the last few decades have had limited success. Ideally, future research and development of novel compounds need to address both the HIV replication and neuroinflammation associated with HIV infection in the brain. Brain mononuclear phagocytes (MPs) are the primary instigators of inflammation and HIV protein expression; therefore, adjunctive treatments that act on MPs, such as immunomodulating agents, look promising. In this review, we will highlight recent developments of innovative therapies and discuss future approaches for HIV NCI treatment.
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Affiliation(s)
- Aaron Scanlan
- Atlanta Veterans Affairs Medical Center, Decatur, GA 30033, USA
- Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Zhan Zhang
- Atlanta Veterans Affairs Medical Center, Decatur, GA 30033, USA
- Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Rajeth Koneru
- Atlanta Veterans Affairs Medical Center, Decatur, GA 30033, USA
| | - Monica Reece
- Department of Pathology, Division of Experimental Pathology, Emory University, Atlanta, GA 30322, USA
- Department of Pharmacology and Chemical Biology, Emory University, Atlanta, GA 30322, USA
| | - Christina Gavegnano
- Department of Pathology, Division of Experimental Pathology, Emory University, Atlanta, GA 30322, USA
- Department of Pharmacology and Chemical Biology, Emory University, Atlanta, GA 30322, USA
| | - Albert M. Anderson
- Department of Medicine, Division of Infectious Diseases, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - William Tyor
- Atlanta Veterans Affairs Medical Center, Decatur, GA 30033, USA
- Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA
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2
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Zorrilla Veloz RI, McKenzie T, Palacios BE, Hu J. Nuclear hormone receptors in demyelinating diseases. J Neuroendocrinol 2022; 34:e13171. [PMID: 35734821 PMCID: PMC9339486 DOI: 10.1111/jne.13171] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 04/20/2022] [Accepted: 05/27/2022] [Indexed: 11/28/2022]
Abstract
Demyelination results from the pathological loss of myelin and is a hallmark of many neurodegenerative diseases. Despite the prevalence of demyelinating diseases, there are no disease modifying therapies that prevent the loss of myelin or promote remyelination. This review aims to summarize studies in the field that highlight the importance of nuclear hormone receptors in the promotion and maintenance of myelination and the relevance of nuclear hormone receptors as potential therapeutic targets for demyelinating diseases. These nuclear hormone receptors include the estrogen receptor, progesterone receptor, androgen receptor, vitamin D receptor, thyroid hormone receptor, peroxisome proliferator-activated receptor, liver X receptor, and retinoid X receptor. Pre-clinical studies in well-established animal models of demyelination have shown a prominent role of these nuclear hormone receptors in myelination through their promotion of oligodendrocyte maturation and development. The activation of the nuclear hormone receptors by their ligands also promotes the synthesis of myelin proteins and lipids in mouse models of demyelination. There are limited clinical studies that focus on how the activation of these nuclear hormone receptors could alleviate demyelination in patients with diseases such as multiple sclerosis (MS). However, the completed clinical trials have reported improved clinical outcome in MS patients treated with the ligands of some of these nuclear hormone receptors. Together, the positive results from both clinical and pre-clinical studies point to nuclear hormone receptors as promising therapeutic targets to counter demyelination.
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Affiliation(s)
- Rocío I Zorrilla Veloz
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Cancer Biology Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
| | - Takese McKenzie
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Neuroscience Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
| | - Bridgitte E Palacios
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Cancer Biology Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
- Neuroscience Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
| | - Jian Hu
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Cancer Biology Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
- Neuroscience Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
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3
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Neuroprotective and Anti-inflammatory Effects of Pioglitazone on Traumatic Brain Injury. Mediators Inflamm 2022; 2022:9860855. [PMID: 35757108 PMCID: PMC9232315 DOI: 10.1155/2022/9860855] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 05/06/2022] [Accepted: 05/24/2022] [Indexed: 02/07/2023] Open
Abstract
Traumatic brain injury (TBI) is still a major cause of concern for public health, and out of all the trauma-related injuries, it makes the highest contribution to death and disability worldwide. Patients of TBI continue to suffer from brain injury through an intricate flow of primary and secondary injury events. However, when treatment is provided in a timely manner, there is a significant window of opportunity to avoid a few of the serious effects. Pioglitazone (PG), which has a neuroprotective impact and can decrease inflammation after TBI, activates peroxisome proliferator-activated receptor-gamma (PPARγ). The objective of the study is to examine the existing literature to assess the neuroprotective and anti-inflammatory impact of PG in TBI. It also discusses the part played by microglia and cytokines in TBI. According to the findings of this study, PG has the ability to enhance neurobehavior, decrease brain edema and neuronal injury following TBI. To achieve the protective impact of PG the following was required: (1) stimulating PPARγ; (2) decreasing oxidative stress; (3) decreasing nuclear factor kappa B (NF-κB), interleukin 6 (IL-6), interleukin-1β (IL-1β), cyclooxygenase-2 (COX-2), and C-C motif chemokine ligand 20 (CCL20) expression; (4) limiting the increase in the number of activated microglia; and (5) reducing mitochondrial dysfunction. The findings indicate that when PIG is used clinically, it may serve as a neuroprotective anti-inflammatory approach in TBI.
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4
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Regulation of Neuroinflammatory Signaling by PPARγ Agonist in Mouse Model of Diabetes. Int J Mol Sci 2022; 23:ijms23105502. [PMID: 35628311 PMCID: PMC9141386 DOI: 10.3390/ijms23105502] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/09/2022] [Accepted: 05/11/2022] [Indexed: 02/01/2023] Open
Abstract
Many relevant studies, as well as clinical practice, confirm that untreated diabetes predisposes the development of neuroinflammation and cognitive impairment. Having regard for the fact that PPARγ are widely distributed in the brain and PPARγ ligands may regulate the inflammatory process, the anti-inflammatory potential of the PPARγ agonist, pioglitazone, was assessed in a mouse model of neuroinflammation related with diabetes. In this regard, the biochemical and molecular indicators of neuroinflammation were determined in the hippocampus and prefrontal cortex of diabetes mice. The levels of cytokines (IL-1β, IL-6, and TNF) and the expression of genes (Tnfrsf1a and Cav1) were measured. In addition, behavioral tests such as the open field test, the hole-board test, and the novel object recognition test were conducted. A 14-day treatment with pioglitazone significantly decreased IL-6 and TNFα levels in the prefrontal cortex and led to the downregulation of Tnfrsf1a expression and the upregulation of Cav1 expression in both brain regions of diabetic mice. Pioglitazone, by targeting neuroinflammatory signaling, improved memory and exploratory activity in behavioral tests. The present study provided a potential theoretical basis and therapeutic target for the treatment of neuroinflammation associated with diabetes. Pioglitazone may provide a promising therapeutic strategy in diabetes patients with muffled of behavioral activity.
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Pompura SL, Hafler DA, Dominguez-Villar M. Fatty Acid Metabolism and T Cells in Multiple Sclerosis. Front Immunol 2022; 13:869197. [PMID: 35603182 PMCID: PMC9116144 DOI: 10.3389/fimmu.2022.869197] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 03/30/2022] [Indexed: 11/25/2022] Open
Abstract
Cellular metabolic remodeling is intrinsically linked to the development, activation, differentiation, function, and survival of T cells. T cells transition from a catabolic, naïve state to an anabolic effector state upon T cell activation. Subsequently, specialization of T cells into T helper (Th) subsets, including regulatory T cells (Treg), requires fine-tuning of metabolic programs that better support and optimize T cell functions for that particular environment. Increasingly, studies have shown that changes in nutrient availability at both the cellular and organismal level during disease states can alter T cell function, highlighting the importance of better characterizing metabolic-immune axes in both physiological and disease settings. In support of these data, a growing body of evidence is emerging that shows specific lipid species are capable of altering the inflammatory functional phenotypes of T cells. In this review we summarize the metabolic programs shown to support naïve and effector T cells, and those driving Th subsets. We then discuss changes to lipid profiles in patients with multiple sclerosis, and focus on how the presence of specific lipid species can alter cellular metabolism and function of T cells.
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Affiliation(s)
- Saige L. Pompura
- Departments of Neurology and Immunobiology, Yale School of Medicine, New Haven, CT, United States
| | - David A. Hafler
- Departments of Neurology and Immunobiology, Yale School of Medicine, New Haven, CT, United States
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Lim SA, Su W, Chapman NM, Chi H. Lipid metabolism in T cell signaling and function. Nat Chem Biol 2022; 18:470-481. [PMID: 35484263 PMCID: PMC11103273 DOI: 10.1038/s41589-022-01017-3] [Citation(s) in RCA: 74] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 03/17/2022] [Indexed: 12/19/2022]
Abstract
T cells orchestrate adaptive immunity against pathogens and other immune challenges, but their dysfunction can also mediate the pathogenesis of cancer and autoimmunity. Metabolic adaptation in response to immunological and microenvironmental signals contributes to T cell function and fate decision. Lipid metabolism has emerged as a key regulator of T cell responses, with selective lipid metabolites serving as metabolic rheostats to integrate environmental cues and interplay with intracellular signaling processes. Here, we discuss how extracellular, de novo synthesized and membrane lipids orchestrate T cell biology. We also describe the roles of lipids as regulators of intracellular signaling at the levels of transcriptional, epigenetic and post-translational regulation in T cells. Finally, we summarize therapeutic targeting of lipid metabolism and signaling, and conclude with a discussion of important future directions. Understanding the molecular and functional interplay between lipid metabolism and T cell biology will ultimately inform therapeutic intervention for human disease.
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Affiliation(s)
- Seon Ah Lim
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Wei Su
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Nicole M Chapman
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Hongbo Chi
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN, USA.
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7
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Willems S, Zaienne D, Merk D. Targeting Nuclear Receptors in Neurodegeneration and Neuroinflammation. J Med Chem 2021; 64:9592-9638. [PMID: 34251209 DOI: 10.1021/acs.jmedchem.1c00186] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Nuclear receptors, also known as ligand-activated transcription factors, regulate gene expression upon ligand signals and present as attractive therapeutic targets especially in chronic diseases. Despite the therapeutic relevance of some nuclear receptors in various pathologies, their potential in neurodegeneration and neuroinflammation is insufficiently established. This perspective gathers preclinical and clinical data for a potential role of individual nuclear receptors as future targets in Alzheimer's disease, Parkinson's disease, and multiple sclerosis, and concomitantly evaluates the level of medicinal chemistry targeting these proteins. Considerable evidence suggests the high promise of ligand-activated transcription factors to counteract neurodegenerative diseases with a particularly high potential of several orphan nuclear receptors. However, potent tools are lacking for orphan receptors, and limited central nervous system exposure or insufficient selectivity also compromises the suitability of well-studied nuclear receptor ligands for functional studies. Medicinal chemistry efforts are needed to develop dedicated high-quality tool compounds for the therapeutic validation of nuclear receptors in neurodegenerative pathologies.
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Affiliation(s)
- Sabine Willems
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Strasse 9, 60438 Frankfurt, Germany
| | - Daniel Zaienne
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Strasse 9, 60438 Frankfurt, Germany
| | - Daniel Merk
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Strasse 9, 60438 Frankfurt, Germany
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8
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Strosznajder AK, Wójtowicz S, Jeżyna MJ, Sun GY, Strosznajder JB. Recent Insights on the Role of PPAR-β/δ in Neuroinflammation and Neurodegeneration, and Its Potential Target for Therapy. Neuromolecular Med 2020; 23:86-98. [PMID: 33210212 PMCID: PMC7929960 DOI: 10.1007/s12017-020-08629-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 10/28/2020] [Indexed: 02/07/2023]
Abstract
Peroxisome proliferator-activated receptor (PPAR) β/δ belongs to the family of hormone and lipid-activated nuclear receptors, which are involved in metabolism of long-chain fatty acids, cholesterol, and sphingolipids. Similar to PPAR-α and PPAR-γ, PPAR-β/δ also acts as a transcription factor activated by dietary lipids and endogenous ligands, such as long-chain saturated and polyunsaturated fatty acids, and selected lipid metabolic products, such as eicosanoids, leukotrienes, lipoxins, and hydroxyeicosatetraenoic acids. Together with other PPARs, PPAR-β/δ displays transcriptional activity through interaction with retinoid X receptor (RXR). In general, PPARs have been shown to regulate cell differentiation, proliferation, and development and significantly modulate glucose, lipid metabolism, mitochondrial function, and biogenesis. PPAR-β/δ appears to play a special role in inflammatory processes and due to its proangiogenic and anti-/pro-carcinogenic properties, this receptor has been considered as a therapeutic target for treating metabolic syndrome, dyslipidemia, carcinogenesis, and diabetes. Until now, most studies were carried out in the peripheral organs, and despite of its presence in brain cells and in different brain regions, its role in neurodegeneration and neuroinflammation remains poorly understood. This review is intended to describe recent insights on the impact of PPAR-β/δ and its novel agonists on neuroinflammation and neurodegenerative disorders, including Alzheimer’s and Parkinson’s, Huntington’s diseases, multiple sclerosis, stroke, and traumatic injury. An important goal is to obtain new insights to better understand the dietary and pharmacological regulations of PPAR-β/δ and to find promising therapeutic strategies that could mitigate these neurological disorders.
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Affiliation(s)
- Anna K Strosznajder
- Faculty of Medicine, Medical University of Bialystok, 1 Kilinskiego st., 15-089, Białystok, Poland
| | - Sylwia Wójtowicz
- Department of Cellular Signaling, Mossakowski Medical Research Centre Polish Academy of Sciences, 5 Pawińskiego st., 02-106, Warsaw, Poland
| | - Mieszko J Jeżyna
- Faculty of Medicine, Medical University of Bialystok, 1 Kilinskiego st., 15-089, Białystok, Poland
| | - Grace Y Sun
- Biochemistry Department, University of Missouri, Columbia, MO, 65211, USA
| | - Joanna B Strosznajder
- Department of Cellular Signaling, Mossakowski Medical Research Centre Polish Academy of Sciences, 5 Pawińskiego st., 02-106, Warsaw, Poland.
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9
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Omeragic A, Kayode O, Hoque MT, Bendayan R. Potential pharmacological approaches for the treatment of HIV-1 associated neurocognitive disorders. Fluids Barriers CNS 2020; 17:42. [PMID: 32650790 PMCID: PMC7350632 DOI: 10.1186/s12987-020-00204-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 06/30/2020] [Indexed: 02/06/2023] Open
Abstract
HIV associated neurocognitive disorders (HAND) are the spectrum of cognitive impairments present in patients infected with human immunodeficiency virus type 1 (HIV-1). The number of patients affected with HAND ranges from 30 to 50% of HIV infected individuals and although the development of combinational antiretroviral therapy (cART) has improved longevity, HAND continues to pose a significant clinical problem as the current standard of care does not alleviate or prevent HAND symptoms. At present, the pathological mechanisms contributing to HAND remain unclear, but evidence suggests that it stems from neuronal injury due to chronic release of neurotoxins, chemokines, viral proteins, and proinflammatory cytokines secreted by HIV-1 activated microglia, macrophages and astrocytes in the central nervous system (CNS). Furthermore, the blood-brain barrier (BBB) not only serves as a route for HIV-1 entry into the brain but also prevents cART therapy from reaching HIV-1 brain reservoirs, and therefore could play an important role in HAND. The goal of this review is to discuss the current data on the epidemiology, pathology and research models of HAND as well as address the potential pharmacological treatment approaches that are being investigated.
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Affiliation(s)
- Amila Omeragic
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Room 1001, Toronto, ON, M5S 3M2, Canada
| | - Olanre Kayode
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Room 1001, Toronto, ON, M5S 3M2, Canada
| | - Md Tozammel Hoque
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Room 1001, Toronto, ON, M5S 3M2, Canada
| | - Reina Bendayan
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Room 1001, Toronto, ON, M5S 3M2, Canada.
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10
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Kadayat TM, Shrestha A, Jeon YH, An H, Kim J, Cho SJ, Chin J. Targeting Peroxisome Proliferator-Activated Receptor Delta (PPARδ): A Medicinal Chemistry Perspective. J Med Chem 2020; 63:10109-10134. [DOI: 10.1021/acs.jmedchem.9b01882] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Tara Man Kadayat
- New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation, Daegu 41061, Republic of Korea
| | - Aarajana Shrestha
- New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation, Daegu 41061, Republic of Korea
- College of Pharmacy, Yeungnam University, Gyeongsan 38541, Republic of Korea
| | - Yong Hyun Jeon
- Laboratory Animal Center, Daegu-Gyeongbuk Medical Innovation Foundation, Daegu 41061, Republic of Korea
- Leading-edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu 41404, Republic of Korea
| | - Hongchan An
- New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation, Daegu 41061, Republic of Korea
| | - Jina Kim
- New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation, Daegu 41061, Republic of Korea
| | - Sung Jin Cho
- New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation, Daegu 41061, Republic of Korea
- Leading-edge Research Center for Drug Discovery and Development for Diabetes and Metabolic Disease, Kyungpook National University Hospital, Daegu 41404, Republic of Korea
| | - Jungwook Chin
- New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation, Daegu 41061, Republic of Korea
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Deng Y, Jiang X, Deng X, Chen H, Xu J, Zhang Z, Liu G, Yong Z, Yuan C, Sun X, Wang C. Pioglitazone ameliorates neuronal damage after traumatic brain injury via the PPARγ/NF-κB/IL-6 signaling pathway. Genes Dis 2020; 7:253-265. [PMID: 32215295 PMCID: PMC7083749 DOI: 10.1016/j.gendis.2019.05.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 05/12/2019] [Accepted: 05/20/2019] [Indexed: 02/06/2023] Open
Abstract
Traumatic brain injury (TBI) is the major cause of high mortality and disability rates worldwide. Pioglitazone is an activator of peroxisome proliferator-activated receptor-gamma (PPARγ) that can reduce inflammation following TBI. Clinically, neuroinflammation after TBI lacks effective treatment. Although there are many studies on PPARγ in TBI animals, only few could be converted into clinical, since TBI mechanisms in humans and animals are not completely consistent. The present study, provided a potential theoretical basis and therapeutic target for neuroinflammation treatment after TBI. First, we detected interleukin-6 (IL-6), nitric oxide (NO) and Caspase-3 in TBI clinical specimens, confirming a presence of a high expression of inflammatory factors. Western blot (WB), quantitative real-time PCR (qRT-PCR) and immunohistochemistry (IHC) were used to detect PPARγ, IL-6, and p-NF-κB to identify the mechanisms of neuroinflammation. Then, in the rat TBI model, neurobehavioral and cerebral edema levels were investigated after intervention with pioglitazone (PPARγ activator) or T0070907 (PPARγ inhibitor), and PPARγ, IL-6 and p-NF-κB were detected again by qRT-PCR, WB and immunofluorescence (IF). The obtained results revealed that: 1) increased expression of IL-6, NO and Caspase-3 in serum and cerebrospinal fluid in patients after TBI, and decreased PPARγ in brain tissue; 2) pioglitazone could improve neurobehavioral and reduce brain edema in rats after TBI; 3) the protective effect of pioglitazone was achieved by activating PPARγ and reducing NF-κB and IL-6. The neuroprotective effect of pioglitazone on TBI was mediated through the PPARγ/NF-κB/IL-6 pathway.
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Affiliation(s)
- Yongbing Deng
- Department of Neurosurgery of the First Affiliated Hospital of Chongqing Medical University, Yixueyuan Road #1, Chongqing, 400016, PR China
- Department of Neurosurgery of the Chongqing Emergency Medical Center, Jiankang Road #1, Chongqing, 400014, PR China
| | - Xue Jiang
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Yixueyuan Road #1, Chongqing, 400016, PR China
| | - Xiaoyan Deng
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Yixueyuan Road #1, Chongqing, 400016, PR China
| | - Hong Chen
- Department of Neurosurgery of the First Affiliated Hospital of Chongqing Medical University, Yixueyuan Road #1, Chongqing, 400016, PR China
| | - Jie Xu
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Yixueyuan Road #1, Chongqing, 400016, PR China
| | - Zhaosi Zhang
- Department of Neurosurgery of the First Affiliated Hospital of Chongqing Medical University, Yixueyuan Road #1, Chongqing, 400016, PR China
| | - Geli Liu
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Yixueyuan Road #1, Chongqing, 400016, PR China
| | - Zhu Yong
- Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, Irvine, CA 92697, USA
| | - Chengfu Yuan
- College of Medical Science, China Three Gorges University, Yichang, Hubei, 443002, PR China
| | - Xiaochuan Sun
- Department of Neurosurgery of the First Affiliated Hospital of Chongqing Medical University, Yixueyuan Road #1, Chongqing, 400016, PR China
| | - Changdong Wang
- Department of Biochemistry and Molecular Biology, Molecular Medicine and Cancer Research Center, Chongqing Medical University, Yixueyuan Road #1, Chongqing, 400016, PR China
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12
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Drohomyrecky PC, Doroshenko ER, Akkermann R, Moshkova M, Yi TJ, Zhao FL, Ahn JJ, McGaha TL, Pahan K, Dunn SE. Peroxisome Proliferator-Activated Receptor-δ Acts within Peripheral Myeloid Cells to Limit Th Cell Priming during Experimental Autoimmune Encephalomyelitis. THE JOURNAL OF IMMUNOLOGY 2019; 203:2588-2601. [PMID: 31578267 DOI: 10.4049/jimmunol.1801200] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 09/02/2019] [Indexed: 12/14/2022]
Abstract
Peroxisome proliferator-activated receptor (PPAR)-δ is a fatty acid-activated transcription factor that regulates metabolic homeostasis, cell growth, and differentiation. Previously, we reported that mice with a global deficiency of PPAR-δ develop an exacerbated course of experimental autoimmune encephalomyelitis (EAE), highlighting a role for this nuclear receptor in limiting the development of CNS inflammation. However, the cell-specific contribution of PPAR-δ to the more severe CNS inflammatory response remained unclear. In this study, we studied the specific involvement of PPAR-δ in myeloid cells during EAE using mice that had Cre-mediated excision of floxed Ppard driven by the lysozyme M (LysM) promoter (LysM Cre :Ppard fl/fl). We observed that LysM Cre :Ppard fl/fl mice were more susceptible to EAE and developed a more severe course of this disease compared with Ppard fl/fl controls. The more severe EAE in LysM Cre :Ppard fl/fl mice was associated with an increased accumulation of pathogenic CD4+ T cells in the CNS and enhanced myelin-specific Th1 and Th17 responses in the periphery. Adoptive transfer EAE studies linked this EAE phenotype in LysM Cre :Ppard fl/fl mice to heightened Th responses. Furthermore, studies using an in vitro CD11b+ cell:Th cell coculture system revealed that CD11b+CD11c+ dendritic cells (DC) from LysM Cre :Ppard fl/fl mice had a heightened capacity to prime myelin oligodendrocyte glycoprotein (MOG)-specific Th cells compared with Ppard fl/fl counterparts; the effects of DC on Th1 cytokine production were mediated through production of the IL-12p40 homodimer. These studies revealed a role for PPAR-δ in DC in limiting Th cell priming during EAE.
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Affiliation(s)
| | | | - Rainer Akkermann
- Toronto General Hospital Research Institute, Toronto, Ontario M5G 2C4, Canada
| | - Marina Moshkova
- Toronto General Hospital Research Institute, Toronto, Ontario M5G 2C4, Canada
| | - Tae Joon Yi
- Department of Immunology, University of Toronto, Toronto, Ontario M5S 1A8, Canada.,Toronto General Hospital Research Institute, Toronto, Ontario M5G 2C4, Canada
| | - Fei L Zhao
- Department of Immunology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Jeeyoon Jennifer Ahn
- Department of Immunology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Tracy L McGaha
- Department of Immunology, University of Toronto, Toronto, Ontario M5S 1A8, Canada.,Princess Margaret Cancer Centre, Toronto, Ontario M5G 2M9, Canada
| | - Kalipada Pahan
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL 60612
| | - Shannon E Dunn
- Department of Immunology, University of Toronto, Toronto, Ontario M5S 1A8, Canada; .,Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Ontario M5B 1W8, Canada; and.,Women's College Research Institute, Toronto, Ontario M5G 1N8, Canada
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13
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Cao J, Hu Y, Shazeeb MS, Pedraza CE, Pande N, Weinstock D, Polites GH, Zhang W, Chandross KJ, Ying X. In Vivo Optical Imaging of Myelination Events in a Myelin Basic Protein Promoter-Driven Luciferase Transgenic Mouse Model. ASN Neuro 2019; 10:1759091418777329. [PMID: 29806482 PMCID: PMC5987236 DOI: 10.1177/1759091418777329] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The compact myelin sheath is important for axonal function, and its loss
can lead to neuronal cell death and irreversible functional deficits.
Myelin is vulnerable to a variety of metabolic, toxic, and autoimmune
insults. In diseases like multiple sclerosis, there is currently no
therapy to stop myelin loss, underscoring the need for neuroprotective
and remyelinating therapies. Noninvasive, robust techniques are also
needed to confirm the effect of such therapies in animal models. This
article describes the generation, characterization, and potential uses
for a myelin basic protein-luciferase (MBP-luci) transgenic mouse
model, in which the firefly luciferase reporter gene is selectively
controlled by the MBP promoter. In vivo
bioluminescence imaging can be used to visualize and quantify
demyelination and remyelination at the transcriptional level,
noninvasively, and in real time. Transgenic mice were assessed in the
cuprizone-induced model of demyelination, and luciferase activity
highly correlated with demyelination and remyelination events as
confirmed by both magnetic resonance imaging and postmortem
histological analysis. Furthermore, MBP-luci mice demonstrated
enhanced luciferase signal and remyelination in the cuprizone model
after treatment with a peroxisome proliferator activated
receptor-delta selective agonist and quetiapine. Imaging sensitivity
was further enhanced by using CycLuc 1, a luciferase substrate, which
has greater blood–brain barrier penetration. We demonstrated the
utility of MBP-luci model in tracking myelin changes in real time and
supporting target and therapeutic validation efforts.
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Affiliation(s)
- James Cao
- 1 Translational In Vivo Model, Global Research Platform, Sanofi R&D, Framingham, MA, USA
| | - Yanping Hu
- 2 Multiple Sclerosis Cluster, Neuroscience Research, Sanofi R&D, Framingham, MA, USA
| | | | - Carlos E Pedraza
- 2 Multiple Sclerosis Cluster, Neuroscience Research, Sanofi R&D, Framingham, MA, USA
| | - Nilesh Pande
- 2 Multiple Sclerosis Cluster, Neuroscience Research, Sanofi R&D, Framingham, MA, USA
| | | | | | - Wenfei Zhang
- 5 Biostatistics and Programming, Sanofi R&D, Framingham, MA, USA
| | | | - Xiaoyou Ying
- 1 Translational In Vivo Model, Global Research Platform, Sanofi R&D, Framingham, MA, USA
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14
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Chen F, Yu X, Meng G, Mei Z, Du Y, Sun H, Reed MN, Kong L, Suppiramaniam V, Hong H, Tang S. Hippocampal Genetic Knockdown of PPARδ Causes Depression-Like Behaviors and Neurogenesis Suppression. Int J Neuropsychopharmacol 2019; 22:372-382. [PMID: 31038173 PMCID: PMC6545535 DOI: 10.1093/ijnp/pyz008] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 12/04/2018] [Accepted: 03/04/2019] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Although depression is the leading cause of disability worldwide, its pathophysiology is poorly understood. Our previous study showed that hippocampal peroxisome proliferator-activated receptor δ (PPARδ) overexpression displays antidepressive effect and enhances hippocampal neurogenesis during chronic stress. Herein, we further extended our curiosity to investigate whether downregulating PPARδ could cause depressive-like behaviors through downregulation of neurogenesis. METHODS Stereotaxic injection of lentiviral vector, expressing short hairpin RNA complementary to the coding exon of PPARδ, was done into the bilateral dentate gyri of the hippocampus, and the depression-like behaviors were observed in mice. Additionally, hippocampal neurogenesis, brain-derived neurotrophic factor and cAMP response element-binding protein were measured both in vivo and in vitro. RESULTS Hippocampal PPARδ knockdown caused depressive-like behaviors and significantly decreased neurogenesis, neuronal differentiation, levels of mature brain-derived neurotrophic factor and phosphorylated cAMP response element-binding protein in the hippocampus. In vitro study further confirmed that PPARδ knockdown could inhibit proliferation and differentiation of neural stem cells. Furthermore, these effects were mimicked by repeated systemic administration of a PPARδ antagonist, GSK0660 (1 or 3 mg/kg i.p. for 21 d). CONCLUSIONS These findings suggest that downregulation of hippocampal PPARδ is associated with depressive behaviors in mice through an inhibitory effect on cAMP response element-binding protein/brain-derived neurotrophic factor-mediated adult neurogenesis in the hippocampus, providing new insights into the pathogenesis of depression.
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Affiliation(s)
- Fang Chen
- Department of Pharmacy, the First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China,Key Laboratory of Neuropsychiatric Diseases, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Xuben Yu
- Key Laboratory of Neuropsychiatric Diseases, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu, China,Department of Pharmacy,First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Guoliang Meng
- School of Pharmacy, Nantong University, Nantong, Jiangsu, China
| | - Zhenlin Mei
- Key Laboratory of Neuropsychiatric Diseases, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Yifeng Du
- Department of Drug Discovery and Development, School of Pharmacy, Auburn University, Auburn, Alabama
| | - Hongbin Sun
- Key Laboratory of Neuropsychiatric Diseases, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Miranda N Reed
- Department of Drug Discovery and Development, School of Pharmacy, Auburn University, Auburn, Alabama
| | - Lingyi Kong
- Key Laboratory of Neuropsychiatric Diseases, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Vishnu Suppiramaniam
- Department of Drug Discovery and Development, School of Pharmacy, Auburn University, Auburn, Alabama
| | - Hao Hong
- Department of Pharmacy, the First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China,Key Laboratory of Neuropsychiatric Diseases, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu, China,Correspondence: Susu Tang, PhD (), and Hao Hong, PhD (), Key Laboratory of Neuropsychiatric Diseases, China Pharmaceutical University, Nanjing 210009, China
| | - Susu Tang
- Department of Pharmacy, the First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China,Correspondence: Susu Tang, PhD (), and Hao Hong, PhD (), Key Laboratory of Neuropsychiatric Diseases, China Pharmaceutical University, Nanjing 210009, China
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15
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Fakan B, Szalardy L, Vecsei L. Exploiting the Therapeutic Potential of Endogenous Immunomodulatory Systems in Multiple Sclerosis-Special Focus on the Peroxisome Proliferator-Activated Receptors (PPARs) and the Kynurenines. Int J Mol Sci 2019; 20:ijms20020426. [PMID: 30669473 PMCID: PMC6358998 DOI: 10.3390/ijms20020426] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 01/13/2019] [Accepted: 01/15/2019] [Indexed: 01/20/2023] Open
Abstract
Multiple sclerosis (MS) is a progressive neurodegenerative disease, characterized by autoimmune central nervous system (CNS) demyelination attributable to a disturbed balance between encephalitic T helper 1 (Th1) and T helper 17 (Th17) and immunomodulatory regulatory T cell (Treg) and T helper 2 (Th2) cells, and an alternatively activated macrophage (M2) excess. Endogenous molecular systems regulating these inflammatory processes have recently been investigated to identify molecules that can potentially influence the course of the disease. These include the peroxisome proliferator-activated receptors (PPARs), PPARγ coactivator-1alpha (PGC-1α), and kynurenine pathway metabolites. Although all PPARs ameliorate experimental autoimmune encephalomyelitis (EAE), recent evidence suggests that PPARα, PPARβ/δ agonists have less pronounced immunomodulatory effects and, along with PGC-1α, are not biomarkers of neuroinflammation in contrast to PPARγ. Small clinical trials with PPARγ agonists have been published with positive results. Proposed as immunomodulatory and neuroprotective, the therapeutic use of PGC-1α activation needs to be assessed in EAE/MS. The activation of indolamine 2,3-dioxygenase (IDO), the rate-limiting step of the kynurenine pathway of tryptophan (Trp) metabolism, plays crucial immunomodulatory roles. Indeed, Trp metabolites have therapeutic relevance in EAE and drugs with structural analogy to kynurenines, such as teriflunomide, are already approved for MS. Further studies are required to gain deeper knowledge of such endogenous immunomodulatory pathways with potential therapeutic implications in MS.
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Affiliation(s)
- Bernadett Fakan
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, H-6725 Szeged, Semmelweis u. 6, Hungary.
| | - Levente Szalardy
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, H-6725 Szeged, Semmelweis u. 6, Hungary.
| | - Laszlo Vecsei
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, H-6725 Szeged, Semmelweis u. 6, Hungary.
- MTA-SZTE Neuroscience Research Group, H-6725 Szeged, Semmelweis u. 6, Hungary.
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16
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Ahmad SF, Nadeem A, Ansari MA, Bakheet SA, Alshammari MA, Attia SM. The PPARδ agonist GW0742 restores neuroimmune function by regulating Tim-3 and Th17/Treg-related signaling in the BTBR autistic mouse model. Neurochem Int 2018; 120:251-261. [DOI: 10.1016/j.neuint.2018.09.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Revised: 09/06/2018] [Accepted: 09/12/2018] [Indexed: 12/12/2022]
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17
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Govindarajulu M, Pinky PD, Bloemer J, Ghanei N, Suppiramaniam V, Amin R. Signaling Mechanisms of Selective PPAR γ Modulators in Alzheimer's Disease. PPAR Res 2018; 2018:2010675. [PMID: 30420872 PMCID: PMC6215547 DOI: 10.1155/2018/2010675] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 08/31/2018] [Accepted: 09/13/2018] [Indexed: 01/22/2023] Open
Abstract
Alzheimer's disease (AD) is a chronic neurodegenerative disease characterized by abnormal protein accumulation, synaptic dysfunction, and cognitive impairment. The continuous increase in the incidence of AD with the aged population and mortality rate indicates the urgent need for establishing novel molecular targets for therapeutic potential. Peroxisome proliferator-activated receptor gamma (PPARγ) agonists such as rosiglitazone and pioglitazone reduce amyloid and tau pathologies, inhibit neuroinflammation, and improve memory impairments in several rodent models and in humans with mild-to-moderate AD. However, these agonists display poor blood brain barrier permeability resulting in inadequate bioavailability in the brain and thus requiring high dosing with chronic time frames. Furthermore, these dosing levels are associated with several adverse effects including increased incidence of weight gain, liver abnormalities, and heart failure. Therefore, there is a need for identifying novel compounds which target PPARγ more selectively in the brain and could provide therapeutic benefits without a high incidence of adverse effects. This review focuses on how PPARγ agonists influence various pathologies in AD with emphasis on development of novel selective PPARγ modulators.
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Affiliation(s)
- Manoj Govindarajulu
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Priyanka D. Pinky
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Jenna Bloemer
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Nila Ghanei
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
| | - Vishnu Suppiramaniam
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
- Center for Neuroscience, Auburn University, Auburn, AL, USA
| | - Rajesh Amin
- Department of Drug Discovery and Development, Harrison School of Pharmacy, Auburn University, Auburn, AL, USA
- Center for Neuroscience, Auburn University, Auburn, AL, USA
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18
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Regulation of Immune Cell Function by PPARs and the Connection with Metabolic and Neurodegenerative Diseases. Int J Mol Sci 2018; 19:ijms19061575. [PMID: 29799467 PMCID: PMC6032042 DOI: 10.3390/ijms19061575] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 05/16/2018] [Accepted: 05/23/2018] [Indexed: 01/01/2023] Open
Abstract
Increasing evidence points towards the existence of a bidirectional interconnection between metabolic disease and neurodegenerative disorders, in which inflammation is linking both together. Activation of members of the peroxisome proliferator-activated receptor (PPAR) family has been shown to have beneficial effects in these interlinked pathologies, and these improvements are often attributed to anti-inflammatory effects of PPAR activation. In this review, we summarize the role of PPARs in immune cell function, with a focus on macrophages and T cells, and how this was shown to contribute to obesity-associated inflammation and insulin resistance, atherosclerosis, and neurodegenerative disorders. We address gender differences as a potential explanation in observed contradictory results, and we highlight PPAR-induced metabolic changes as a potential mechanism of regulation of immune cell function through these nuclear receptors. Together, immune cell-specific activation of PPARs present a promising therapeutic approach to treat both metabolic and neurodegenerative diseases.
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19
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Lee WJ, Ham SA, Yoo H, Hwang JS, Yoo T, Paek KS, Lim DS, Han SG, Lee CH, Hong K, Seo HG. Activation of PPARδ attenuates neurotoxicity by inhibiting lipopolysaccharide-triggered glutamate release in BV-2 microglial cells. J Cell Biochem 2018; 119:5609-5619. [PMID: 29388693 DOI: 10.1002/jcb.26732] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 01/29/2018] [Indexed: 12/25/2022]
Abstract
Neuroinflammation-associated release of glutamate from activated microglia has been implicated in the progression of neurodegenerative diseases. However, the regulatory mechanisms underlying this glutamate release are poorly understood. Here, we show that peroxisome proliferator-activated receptor delta (PPARδ) modulates neurotoxicity by inhibiting glutamate release in lipopolysaccharide (LPS)-activated BV-2 microglial cells. Activation of PPARδ by GW501516, a specific PPARδ agonist, inhibited glutamate release in BV-2 cells. This effect of GW501516 was significantly blocked by shRNA-mediated knockdown of PPARδ and by treatment with GSK0660, a specific PPARδ antagonist, indicating that PPARδ is associated with blockade of glutamate release. Additionally, GW501516-activated PPARδ suppressed generation of reactive oxygen species and expression of gp91phox, a functional subunit of NADPH oxidase 2, in BV-2 cells stimulated with LPS. The inhibitory effect of GW501516 on gp91phox expression and glutamate release was further potentiated in the presence of AG490, a specific inhibitor of janus kinase 2 (JAK2), leading to the inhibition of signal transducer and activator of transcription 1 (STAT1). By contrast, GW501516 upregulated the expression of suppressor of cytokine signaling 1 (SOCS1), an endogenous inhibitor of JAK2. Furthermore, neurotoxicity induced by conditioned media from LPS-stimulated BV-2 cells was significantly reduced when conditioned media from BV-2 cells treated with both LPS and GW501516 were used. These results indicate that PPARδ attenuates LPS-triggered neuroinflammation by enhancing SOCS1-mediated inhibition of JAK2/STAT1 signaling, thereby inhibiting neurotoxicity associated with glutamate release.
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Affiliation(s)
- Won Jin Lee
- Sanghuh College of Life Sciences, Konkuk University, Gwangjin-gu, Seoul, Korea
| | - Sun Ah Ham
- Sanghuh College of Life Sciences, Konkuk University, Gwangjin-gu, Seoul, Korea
| | - Hyunjin Yoo
- Department of Stem Cell & Regenerative Biotechnology, Konkuk University, Gwangjin-gu, Seoul, Korea
| | - Jung Seok Hwang
- Sanghuh College of Life Sciences, Konkuk University, Gwangjin-gu, Seoul, Korea
| | - Taesik Yoo
- Sanghuh College of Life Sciences, Konkuk University, Gwangjin-gu, Seoul, Korea
| | | | - Dae-Seog Lim
- Department of Biotechnology, CHA University, Bundang-gu, Seongnam, Korea
| | - Sung Gu Han
- Sanghuh College of Life Sciences, Konkuk University, Gwangjin-gu, Seoul, Korea
| | - Chi-Ho Lee
- Sanghuh College of Life Sciences, Konkuk University, Gwangjin-gu, Seoul, Korea
| | - Kwonho Hong
- Department of Stem Cell & Regenerative Biotechnology, Konkuk University, Gwangjin-gu, Seoul, Korea
| | - Han Geuk Seo
- Sanghuh College of Life Sciences, Konkuk University, Gwangjin-gu, Seoul, Korea
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20
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Howie D, Ten Bokum A, Necula AS, Cobbold SP, Waldmann H. The Role of Lipid Metabolism in T Lymphocyte Differentiation and Survival. Front Immunol 2018; 8:1949. [PMID: 29375572 PMCID: PMC5770376 DOI: 10.3389/fimmu.2017.01949] [Citation(s) in RCA: 109] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 12/18/2017] [Indexed: 12/22/2022] Open
Abstract
The differentiation and effector functions of both the innate and adaptive immune system are inextricably linked to cellular metabolism. The features of metabolism which affect both arms of the immune system include metabolic substrate availability, expression of enzymes, transport proteins, and transcription factors which control catabolism of these substrates, and the ability to perform anabolic metabolism. The control of lipid metabolism is central to the appropriate differentiation and functions of T lymphocytes, and ultimately to the maintenance of immune tolerance. This review will focus on the role of fatty acid (FA) metabolism in T cell differentiation, effector function, and survival. FAs are important sources of cellular energy, stored as triglycerides. They are also used as precursors to produce complex lipids such as cholesterol and membrane phospholipids. FA residues also become incorporated into hormones and signaling moieties. FAs signal via nuclear receptors and their channeling, between storage as triacyl glycerides or oxidation as fuel, may play a role in survival or death of the cell. In recent years, progress in the field of immunometabolism has highlighted diverse roles for FA metabolism in CD4 and CD8 T cell differentiation and function. This review will firstly describe the sensing and modulation of the environmental FAs and lipid intracellular signaling and will then explore the key role of lipid metabolism in regulating the balance between potentially damaging pro-inflammatory and anti-inflammatory regulatory responses. Finally the complex role of extracellular FAs in determining cell survival will be discussed.
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Affiliation(s)
- Duncan Howie
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Annemieke Ten Bokum
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | | | - Stephen Paul Cobbold
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Herman Waldmann
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
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21
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Amici SA, Dong J, Guerau-de-Arellano M. Molecular Mechanisms Modulating the Phenotype of Macrophages and Microglia. Front Immunol 2017; 8:1520. [PMID: 29176977 PMCID: PMC5686097 DOI: 10.3389/fimmu.2017.01520] [Citation(s) in RCA: 126] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 10/26/2017] [Indexed: 12/24/2022] Open
Abstract
Macrophages and microglia play crucial roles during central nervous system development, homeostasis and acute events such as infection or injury. The diverse functions of tissue macrophages and microglia are mirrored by equally diverse phenotypes. A model of inflammatory/M1 versus a resolution phase/M2 macrophages has been widely used. However, the complexity of macrophage function can only be achieved by the existence of varied, plastic and tridimensional macrophage phenotypes. Understanding how tissue macrophages integrate environmental signals via molecular programs to define pathogen/injury inflammatory responses provides an opportunity to better understand the multilayered nature of macrophages, as well as target and modulate cellular programs to control excessive inflammation. This is particularly important in MS and other neuroinflammatory diseases, where chronic inflammatory macrophage and microglial responses may contribute to pathology. Here, we perform a comprehensive review of our current understanding of how molecular pathways modulate tissue macrophage phenotype, covering both classic pathways and the emerging role of microRNAs, receptor-tyrosine kinases and metabolism in macrophage phenotype. In addition, we discuss pathway parallels in microglia, novel markers helpful in the identification of peripheral macrophages versus microglia and markers linked to their phenotype.
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Affiliation(s)
- Stephanie A Amici
- School of Health and Rehabilitation Sciences, Division of Medical Laboratory Science, College of Medicine, Wexner Medical Center, The Ohio State University, Columbus, OH, United States
| | - Joycelyn Dong
- School of Health and Rehabilitation Sciences, Division of Medical Laboratory Science, College of Medicine, Wexner Medical Center, The Ohio State University, Columbus, OH, United States.,McCormick School of Engineering, Division of Biomedical Engineering, Northwestern University, Evanston, IL, United States
| | - Mireia Guerau-de-Arellano
- School of Health and Rehabilitation Sciences, Division of Medical Laboratory Science, College of Medicine, Wexner Medical Center, The Ohio State University, Columbus, OH, United States.,Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, United States.,Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, United States.,Department of Neuroscience, The Ohio State University, Columbus, OH, United States
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22
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Peroxisome proliferator-activated receptor-gamma: potential molecular therapeutic target for HIV-1-associated brain inflammation. J Neuroinflammation 2017; 14:183. [PMID: 28886715 PMCID: PMC5591559 DOI: 10.1186/s12974-017-0957-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 08/31/2017] [Indexed: 12/16/2022] Open
Abstract
Background Despite the use of combination antiretroviral therapy for the treatment of HIV-1 infection, cognitive impairments remain prevalent due to persistent viral replication and associated brain inflammation. Primary cellular targets of HIV-1 in the brain are macrophages, microglia, and to a certain extent astrocytes which in response to infection release inflammatory markers, viral proteins [i.e., glycoprotein 120 (gp120)] and exhibit impaired glutamate uptake. Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear receptor superfamily of ligand-activated transcription factors. Compelling evidence suggests that PPARγ exerts anti-inflammatory properties in neurological disorders. The goal of this study was to examine the role of PPARγ in the context of HIV-1ADA gp120-induced inflammation in vitro, in primary cultures of rat astrocytes and microglia, and in vivo, in a rodent model of HIV-1ADA gp120-associated brain inflammation. Methods Primary mixed cultures of rat astrocytes and microglia were treated with PPARγ agonists (rosiglitazone or pioglitazone) and exposed to HIV-1ADA gp120. Inflammatory cytokines and indicator of oxidative stress response (TNFα, IL-1β, iNOS) were measured using qPCR, and glutamate transporter (GLT-1) was quantified by immunoblotting. In vivo, rats were administered an intracerebroventricular injection of HIV-1ADA gp120 and an intraperitoneal injection of PPARγ agonist (rosiglitazone) or co-administration with PPARγ antagonist (GW9662). qPCR and immunoblotting analyses were applied to measure inflammatory markers, GLT-1 and PPARγ. Results In primary mixed cultures of rat astrocytes and microglia, HIV-1ADA gp120 exposure resulted in a significant elevation of inflammatory markers and a decrease in GLT-1 expression which were significantly attenuated with rosiglitazone or pioglitazone treatment. Similarly, in vivo, treatment with rosiglitazone reversed the gp120-mediated inflammatory response and downregulation of GLT-1. Furthermore, we demonstrated that the anti-inflammatory effects of PPARγ agonist rosiglitazone were mediated through inhibition of NF-κB. Conclusion Our data demonstrate that gp120 can induce an inflammatory response and decrease expression of GLT-1 in the brain in vitro and in vivo. We have also successfully shown that these effects can be reversed by treatment with PPARγ agonists, rosiglitazone or pioglitazone. Together our data suggest that targeting PPARγ signaling may provide an option for preventing/treating HIV-associated brain inflammation. Electronic supplementary material The online version of this article (10.1186/s12974-017-0957-8) contains supplementary material, which is available to authorized users.
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23
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Park HJ, Choi JM. Sex-specific regulation of immune responses by PPARs. Exp Mol Med 2017; 49:e364. [PMID: 28775365 PMCID: PMC5579504 DOI: 10.1038/emm.2017.102] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 02/15/2017] [Accepted: 03/05/2017] [Indexed: 12/18/2022] Open
Abstract
The prevalence of autoimmune, infectious and metabolic diseases is different for men and women owing to the respective ability of their immune systems to respond to self and foreign antigens. Although several factors, including hormones and the X-chromosome, have been suggested to contribute to such sex-specific immune responses, the underlying factors remain poorly defined. Recent studies using peroxisome proliferator-activated receptor (PPAR) ligands and knockout mice have identified sex-dimorphic expression of PPARs, and have shown that the inhibitory functions of PPAR in T cells are substantially affected by the sex hormones. In this review, we consider the sex-specific differences in PPARs and summarize the diverse PPAR-mediated, sex-specific properties of effector T-cell responses, such as T-cell activation, survival and differentiation, as well as their involvement in T-cell-related autoimmune diseases, including colitis, graft-versus-host disease and experimental autoimmune encephalomyelitis. Understanding PPAR-mediated sex differences in immune responses will provide more precise insights into the roles of PPARs in effector T cells.
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Affiliation(s)
- Hong-Jai Park
- Department of Life Science, College of Natural Sciences, Hanyang University, Seoul, Republic of Korea.,Research Institute for Natural Sciences, Hanyang University, Seoul, Republic of Korea
| | - Je-Min Choi
- Department of Life Science, College of Natural Sciences, Hanyang University, Seoul, Republic of Korea.,Research Institute for Natural Sciences, Hanyang University, Seoul, Republic of Korea
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24
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The Role of Nuclear Hormone Receptors in Cannabinoid Function. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2017; 80:291-328. [PMID: 28826538 DOI: 10.1016/bs.apha.2017.03.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Since the early 2000s, evidence has been accumulating that most cannabinoid compounds interact with the nuclear hormone family peroxisome proliferator-activated receptors (PPARs). This can be through direct binding of these compounds to PPARs, metabolism of cannabinoid to other PPAR-activating chemicals, or indirect activation of PPAR through cell signaling pathways. Delivery of cannabinoids to the nucleus may be facilitated by fatty acid-binding proteins and carrier proteins. All PPAR isoforms appear to be activated by cannabinoids, but the majority of evidence is for PPARα and γ. To date, little is known about the potential interaction of cannabinoids with other nuclear hormones. At least some (but not all) of the well-known biological actions of cannabinoids including neuroprotection, antiinflammatory action, and analgesic effects are partly mediated by PPAR-activation, often in combination with activation of the more traditional target sites of action. This has been best investigated for the endocannabinoid-like compounds palmitoylethanolamide and oleoylethanolamine acting at PPARα, and for phytocannabinoids or their derivatives activation acting at PPARγ. However, there are still many aspects of cannabinoid activation of PPAR and the role it plays in the biological and therapeutic effects of cannabinoids that remain to be investigated.
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25
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Szalardy L, Zadori D, Bencsik K, Vecsei L, Klivenyi P. Unlike PPARgamma, neither other PPARs nor PGC-1alpha is elevated in the cerebrospinal fluid of patients with multiple sclerosis. Neurosci Lett 2017; 651:128-133. [PMID: 28483651 DOI: 10.1016/j.neulet.2017.05.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 05/05/2017] [Accepted: 05/05/2017] [Indexed: 02/06/2023]
Abstract
Corroborating with prior experimental findings, we recently reported the pronounced elevation of peroxisome proliferator-activated receptor gamma (PPARγ) protein concentration in the cerebrospinal fluid (CSF) of patients with multiple sclerosis (MS), in association with neuroinflammatory markers and clinical severity. Based on subsequent reports on the possible involvement of other PPARs and PPARγ coactivator-1alpha (PGC-1α) in neuroinflammation in MS, we analyzed the protein levels of PPARα, PPARβ/δ, and PGC-1α in a subset of CSF samples from the same cohort of relapsing-remitting MS patients. Unlike PPARγ, none of these proteins were found elevated in MS patients (n=25) compared to non-inflammatory controls (n=16), with the levels of PPARα and PPARβ/δ found generally below the limit of detection, and that of PGC-1α being detectable but comparable in both groups. The clinical and laboratory associations previously reported with PPARγ were however significant even in this smaller subset. The potential underlying causes of these differential alterations are discussed. The findings suggest that despite their proposed involvement in the regulation of inflammatory processes in MS, PPARα, PPARβ/δ, and PGC-1α proteins are not potential biomarkers of neuroinflammation in MS, and indicate a preferential role of PPARγ in the endogenous regulation of autoimmune response in the human CNS within its receptor family.
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Affiliation(s)
- Levente Szalardy
- Department of Neurology, University of Szeged, H-6725, Szeged, Semmelweis u. 6, Hungary
| | - Denes Zadori
- Department of Neurology, University of Szeged, H-6725, Szeged, Semmelweis u. 6, Hungary
| | - Krisztina Bencsik
- Department of Neurology, University of Szeged, H-6725, Szeged, Semmelweis u. 6, Hungary
| | - Laszlo Vecsei
- Department of Neurology, University of Szeged, H-6725, Szeged, Semmelweis u. 6, Hungary; MTA-SZTE Neuroscience Research Group, H-6725, Szeged, Semmelweis u. 6, Hungary
| | - Peter Klivenyi
- Department of Neurology, University of Szeged, H-6725, Szeged, Semmelweis u. 6, Hungary.
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Bonfiglio T, Olivero G, Merega E, Di Prisco S, Padolecchia C, Grilli M, Milanese M, Di Cesare Mannelli L, Ghelardini C, Bonanno G, Marchi M, Pittaluga A. Prophylactic versus Therapeutic Fingolimod: Restoration of Presynaptic Defects in Mice Suffering from Experimental Autoimmune Encephalomyelitis. PLoS One 2017; 12:e0170825. [PMID: 28125677 PMCID: PMC5268435 DOI: 10.1371/journal.pone.0170825] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 01/11/2017] [Indexed: 11/18/2022] Open
Abstract
Fingolimod, the first oral, disease-modifying therapy for MS, has been recently proposed to modulate glutamate transmission in the central nervous system (CNS) of mice suffering from Experimental Autoimmune Encephalomyelitis (EAE) and in MS patients. Our study aims at investigating whether oral fingolimod recovers presynaptic defects that occur at different stages of disease in the CNS of EAE mice. In vivo prophylactic (0.3 mg/kg for 14 days, from the 7th day post immunization, d.p.i, the drug dissolved in the drinking water) fingolimod significantly reduced the clinical symptoms and the anxiety-related behaviour in EAE mice. Spinal cord inflammation, demyelination and glial cell activation are markers of EAE progression. These signs were ameliorated following oral fingolimod administration. Glutamate exocytosis was shown to be impaired in cortical and spinal cord terminals isolated from EAE mice at 21 ± 1 d.p.i., while GABA alteration emerged only at the spinal cord level. Prophylactic fingolimod recovered these presynaptic defects, restoring altered glutamate and GABA release efficiency. The beneficial effect occurred in a dose-dependent, region-specific manner, since lower (0.1-0.03 mg/kg) doses restored, although to a different extent, synaptic defects in cortical but not spinal cord terminals. A delayed reduction of glutamate, but not of GABA, exocytosis was observed in hippocampal terminals of EAE mice at 35 d.p.i. Therapeutic (0.3 mg/kg, from 21 d.p.i. for 14 days) fingolimod restored glutamate exocytosis in the cortex and in the hippocampus of EAE mice at 35 ± 1 d.p.i. but not in the spinal cord, where also GABAergic defects remained unmodified. These results improve our knowledge of the molecular events accounting for the beneficial effects elicited by fingolimod in demyelinating disorders.
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MESH Headings
- Administration, Oral
- Animals
- Cerebral Cortex/drug effects
- Cerebral Cortex/immunology
- Cerebral Cortex/pathology
- Dose-Response Relationship, Drug
- Encephalomyelitis, Autoimmune, Experimental/drug therapy
- Encephalomyelitis, Autoimmune, Experimental/immunology
- Encephalomyelitis, Autoimmune, Experimental/pathology
- Encephalomyelitis, Autoimmune, Experimental/prevention & control
- Exocytosis/drug effects
- Female
- Fingolimod Hydrochloride/pharmacology
- Glutamic Acid/metabolism
- Glutamic Acid/pharmacology
- Hippocampus/drug effects
- Hippocampus/immunology
- Hippocampus/pathology
- Immunosuppressive Agents/pharmacology
- Mice
- Mice, Inbred C57BL
- Neuroglia/drug effects
- Neuroglia/immunology
- Neuroglia/pathology
- Organ Specificity
- Spinal Cord/drug effects
- Spinal Cord/immunology
- Spinal Cord/pathology
- Synapses/drug effects
- Synapses/immunology
- Synapses/pathology
- gamma-Aminobutyric Acid/metabolism
- gamma-Aminobutyric Acid/pharmacology
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Affiliation(s)
- Tommaso Bonfiglio
- Department of Pharmacy, Pharmacology and Toxicology Section, School of Medical and Pharmaceutical Sciences, University of Genoa, Genoa, Italy
| | - Guendalina Olivero
- Department of Pharmacy, Pharmacology and Toxicology Section, School of Medical and Pharmaceutical Sciences, University of Genoa, Genoa, Italy
| | - Elisa Merega
- Department of Pharmacy, Pharmacology and Toxicology Section, School of Medical and Pharmaceutical Sciences, University of Genoa, Genoa, Italy
| | - Silvia Di Prisco
- Department of Pharmacy, Pharmacology and Toxicology Section, School of Medical and Pharmaceutical Sciences, University of Genoa, Genoa, Italy
| | - Cristina Padolecchia
- Department of Pharmacy, Pharmacology and Toxicology Section, School of Medical and Pharmaceutical Sciences, University of Genoa, Genoa, Italy
| | - Massimo Grilli
- Department of Pharmacy, Pharmacology and Toxicology Section, School of Medical and Pharmaceutical Sciences, University of Genoa, Genoa, Italy
- Center of Excellence for Biomedical Research, University of Genoa, Genoa, Italy
| | - Marco Milanese
- Department of Pharmacy, Pharmacology and Toxicology Section, School of Medical and Pharmaceutical Sciences, University of Genoa, Genoa, Italy
- Center of Excellence for Biomedical Research, University of Genoa, Genoa, Italy
| | - Lorenzo Di Cesare Mannelli
- Department of Neuroscience, Psychology, Drug Research and Child Health, Neurofarba, Pharmacology and Toxicology section, University of Florence, Florence, Italy
| | - Carla Ghelardini
- Department of Neuroscience, Psychology, Drug Research and Child Health, Neurofarba, Pharmacology and Toxicology section, University of Florence, Florence, Italy
| | - Giambattista Bonanno
- Department of Pharmacy, Pharmacology and Toxicology Section, School of Medical and Pharmaceutical Sciences, University of Genoa, Genoa, Italy
- Center of Excellence for Biomedical Research, University of Genoa, Genoa, Italy
| | - Mario Marchi
- Department of Pharmacy, Pharmacology and Toxicology Section, School of Medical and Pharmaceutical Sciences, University of Genoa, Genoa, Italy
- Center of Excellence for Biomedical Research, University of Genoa, Genoa, Italy
| | - Anna Pittaluga
- Department of Pharmacy, Pharmacology and Toxicology Section, School of Medical and Pharmaceutical Sciences, University of Genoa, Genoa, Italy
- Center of Excellence for Biomedical Research, University of Genoa, Genoa, Italy
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Fiander MD, Stifani N, Nichols M, Akay T, Robertson GS. Kinematic gait parameters are highly sensitive measures of motor deficits and spinal cord injury in mice subjected to experimental autoimmune encephalomyelitis. Behav Brain Res 2017; 317:95-108. [DOI: 10.1016/j.bbr.2016.09.034] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 09/12/2016] [Accepted: 09/14/2016] [Indexed: 12/13/2022]
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A role for Peroxisome Proliferator-Activated Receptor Beta in T cell development. Sci Rep 2016; 6:34317. [PMID: 27680392 PMCID: PMC5041207 DOI: 10.1038/srep34317] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Accepted: 09/12/2016] [Indexed: 12/30/2022] Open
Abstract
Metabolism plays an important role in T cell biology and changes in metabolism drive T cell differentiation and fate. Most research on the role of metabolism in T lymphocytes focuses on mature T cells while only few studies have investigated the role of metabolism in T cell development. In this study, we report that activation or overexpression of the transcription factor Peroxisome Proliferator-Activated Receptor β (PPARβ) increases fatty acid oxidation in T cells. Furthermore, using both in vivo and in vitro models, we demonstrate that PPARβ activation/overexpression inhibits thymic T cell development by decreasing proliferation of CD4−CD8− double-negative stage 4 (DN4) thymocytes. These results support a model where PPARβ activation/overexpression favours fatty acid- instead of glucose-oxidation in developing T cells, thereby hampering the proliferative burst normally occurring at the DN4 stage of T cell development. As a consequence, the αβ T cells that are derived from DN4 thymocytes are dramatically decreased in peripheral lymphoid tissues, while the γδ T cell population remains untouched. This is the first report of a direct role for a member of the PPAR family of nuclear receptors in the development of T cells.
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Tan NS, Vázquez-Carrera M, Montagner A, Sng MK, Guillou H, Wahli W. Transcriptional control of physiological and pathological processes by the nuclear receptor PPARβ/δ. Prog Lipid Res 2016; 64:98-122. [PMID: 27665713 DOI: 10.1016/j.plipres.2016.09.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 08/31/2016] [Accepted: 09/20/2016] [Indexed: 12/14/2022]
Affiliation(s)
- Nguan Soon Tan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore; Lee Kong Chian School of Medicine, Nanyang Technological University, Academia, 20 College Road, 169856, Singapore; Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, Agency for Science Technology & Research, 138673, Singapore; KK Research Centre, KK Women's and Children's Hospital, 100 Bukit Timah Road, 229899, Singapore.
| | - Manuel Vázquez-Carrera
- Department of Pharmacology and Therapeutic Chemistry, Faculty of Pharmacy, University of Barcelona, Institute of Biomedicine of the University of Barcelona (IBUB), Pediatric Research Institute-Hospital Sant Joan de Déu, Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Diseases (CIBERDEM), Barcelona, Spain
| | | | - Ming Keat Sng
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore; Lee Kong Chian School of Medicine, Nanyang Technological University, Academia, 20 College Road, 169856, Singapore
| | - Hervé Guillou
- INRA ToxAlim, UMR1331, Chemin de Tournefeuille, Toulouse Cedex 3, France
| | - Walter Wahli
- Lee Kong Chian School of Medicine, Nanyang Technological University, Academia, 20 College Road, 169856, Singapore; INRA ToxAlim, UMR1331, Chemin de Tournefeuille, Toulouse Cedex 3, France; Center for Integrative Genomics, University of Lausanne, Le Génopode, CH 1015 Lausanne, Switzerland.
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30
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Lloyd AF, Miron VE. Cellular and Molecular Mechanisms Underpinning Macrophage Activation during Remyelination. Front Cell Dev Biol 2016; 4:60. [PMID: 27446913 PMCID: PMC4914869 DOI: 10.3389/fcell.2016.00060] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Accepted: 06/06/2016] [Indexed: 12/13/2022] Open
Abstract
Remyelination is an example of central nervous system (CNS) regeneration, whereby myelin is restored around demyelinated axons, re-establishing saltatory conduction and trophic/metabolic support. In progressive multiple sclerosis, remyelination is limited or fails altogether which is considered to contribute to axonal damage/loss and consequent disability. Macrophages have critical roles in both CNS damage and regeneration, such as remyelination. This diverse range in functions reflects the ability of macrophages to acquire tissue microenvironment-specific activation states. This activation is dynamically regulated during efficient regeneration, with a switch from pro-inflammatory to inflammation-resolution/pro-regenerative phenotypes. Although, some molecules and pathways have been implicated in the dynamic activation of macrophages, such as NFκB, the cellular and molecular mechanisms underpinning plasticity of macrophage activation are unclear. Identifying mechanisms regulating macrophage activation to pro-regenerative phenotypes may lead to novel therapeutic strategies to promote remyelination in multiple sclerosis.
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Affiliation(s)
- Amy F Lloyd
- MRC Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh Edinburgh, UK
| | - Veronique E Miron
- MRC Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh Edinburgh, UK
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31
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Iglesias J, Morales L, Barreto GE. Metabolic and Inflammatory Adaptation of Reactive Astrocytes: Role of PPARs. Mol Neurobiol 2016; 54:2518-2538. [PMID: 26984740 DOI: 10.1007/s12035-016-9833-2] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 03/04/2016] [Indexed: 01/10/2023]
Abstract
Astrocyte-mediated inflammation is associated with degenerative pathologies such as Alzheimer's and Parkinson's diseases and multiple sclerosis. The acute inflammation and morphological and metabolic changes that astrocytes develop after the insult are known as reactive astroglia or astrogliosis that is an important response to protect and repair the lesion. Astrocytes optimize their metabolism to produce lactate, glutamate, and ketone bodies in order to provide energy to the neurons that are deprived of nutrients upon insult. Firstly, we review the basis of inflammation and morphological changes of the different cell population implicated in reactive gliosis. Next, we discuss the more active metabolic pathways in healthy astrocytes and explain the metabolic response of astrocytes to the insult in different pathologies and which metabolic alterations generate complications in these diseases. We emphasize the role of peroxisome proliferator-activated receptors isotypes in the inflammatory and metabolic adaptation of astrogliosis developed in ischemia or neurodegenerative diseases. Based on results reported in astrocytes and other cells, we resume and hypothesize the effect of peroxisome proliferator-activated receptor (PPAR) activation with ligands on different metabolic pathways in order to supply energy to the neurons. The activation of selective PPAR isotype activity may serve as an input to better understand the role played by these receptors on the metabolic and inflammatory compensation of astrogliosis and might represent an opportunity to develop new therapeutic strategies against traumatic brain injuries and neurodegenerative diseases.
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Affiliation(s)
- José Iglesias
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá, DC, Colombia.
| | - Ludis Morales
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá, DC, Colombia
| | - George E Barreto
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá, DC, Colombia
- Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile
- Universidad Científica del Sur, Lima, Peru
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32
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Obeticholic acid, a synthetic bile acid agonist of the farnesoid X receptor, attenuates experimental autoimmune encephalomyelitis. Proc Natl Acad Sci U S A 2016; 113:1600-5. [PMID: 26811456 DOI: 10.1073/pnas.1524890113] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Bile acids are ligands for the nuclear hormone receptor, farnesoid X receptor (FXR). The bile acid-FXR interaction regulates bile acid synthesis, transport, and cholesterol metabolism. Recently, bile acid-FXR regulation has been reported to play an integral role in both hepatic and intestinal inflammation, and in atherosclerosis. In this study, we found that FXR knockout mice had more disease severity in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Obeticholic acid (6α-ethyl-chenodeoxycholic acid, 6-ECDCA), a synthetic FXR agonist, is an orally available drug that is currently in clinical trials for the treatment of inflammatory diseases such as alcoholic hepatitis, nonalcoholic steatohepatitis, and primary biliary cirrhosis. When we treated mice exhibiting established EAE with 6-ECDCA, or the natural FXR ligand chenodeoxycholic acid (CDCA), clinical disease was ameliorated by (i) suppressing lymphocyte activation and proinflammatory cytokine production; (ii) reducing CD4(+) T cells and CD19(+) B cell populations and their expression of negative checkpoint regulators programmed cell death protein 1 (PD1), programmed death-ligand 1 (PD-L1), and B and T lymphocyte attenuator (BTLA); (iii) increasing CD8(+) T cells and PD1, PDl-1, and BTLA expression; and (iv) reducing VLA-4 expression in both the T- and B-cell populations. Moreover, adoptive transfer of 6-ECDCA- or CDCA-treated donor cells failed to transfer disease in naive recipients. Thus, we show that FXR functions as a negative regulator in neuroinflammation and we highlight that FXR agonists represent a potential previously unidentified therapy for MS.
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33
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Sandoval-Hernández A, Contreras MJ, Jaramillo J, Arboleda G. Regulation of Oligodendrocyte Differentiation and Myelination by Nuclear Receptors: Role in Neurodegenerative Disorders. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 949:287-310. [DOI: 10.1007/978-3-319-40764-7_14] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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34
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Gardner LA, Levin MC. Importance of Apolipoprotein A-I in Multiple Sclerosis. Front Pharmacol 2015; 6:278. [PMID: 26635608 PMCID: PMC4654019 DOI: 10.3389/fphar.2015.00278] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 11/04/2015] [Indexed: 12/12/2022] Open
Abstract
Jean-Martin Charcot has first described multiple sclerosis (MS) as a disease of the central nervous system (CNS) over a century ago. MS remains incurable today, and treatment options are limited to disease modifying drugs. Over the years, significant advances in understanding disease pathology have been made in autoimmune and neurodegenerative components. Despite the fact that brain is the most lipid rich organ in human body, the importance of lipid metabolism has not been extensively studied in this disorder. In MS, the CNS is under attack by a person's own immune system. Autoantigens and autoantibodies are known to cause devastation of myelin through up regulation of T-cells and cytokines, which penetrate through the blood-brain barrier to cause inflammation and myelin destruction. The anti-inflammatory role of high-density lipoproteins (HDLs) has been implicated in a plethora of biological processes: vasodilation, immunity to infection, oxidation, inflammation, and apoptosis. However, it is not known what role HDL plays in neurological function and myelin repair in MS. Understanding of lipid metabolism in the CNS and in the periphery might unveil new therapeutic targets and explain the partial success of some existing MS therapies.
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Affiliation(s)
- Lidia A. Gardner
- Research Service, VA Medical Center, Memphis, TN, USA
- Department of Neurology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Michael C. Levin
- Research Service, VA Medical Center, Memphis, TN, USA
- Department of Neurology, University of Tennessee Health Science Center, Memphis, TN, USA
- Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN, USA
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35
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Chiaranunt P, Ferrara JLM, Byersdorfer CA. Rethinking the paradigm: How comparative studies on fatty acid oxidation inform our understanding of T cell metabolism. Mol Immunol 2015; 68:564-74. [PMID: 26359186 DOI: 10.1016/j.molimm.2015.07.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Revised: 06/15/2015] [Accepted: 07/19/2015] [Indexed: 02/09/2023]
Abstract
The classic paradigm of T cell metabolism posits that activated Teff cells utilize glycolysis to keep pace with increased energetic demands, while resting and Tmem cells rely on the oxidation of fat. In contrast, Teff cells during graft-versus-host disease (GVHD) increase their reliance on oxidative metabolism and, in particular, on fatty acid oxidation (FAO). To explore the potential mechanisms driving adoption of this alternative metabolism, we first review key pathways regulating FAO across a variety of disparate tissue types, including liver, heart, and skeletal muscle. Based upon these comparative studies, we then outline a consensus network of transcriptional and signaling pathways that predict a model for regulating FAO in Teff cells during GVHD. This model raises important implications about the dynamic nature of metabolic reprogramming in T cells and suggests exciting future directions for further study of in vivo T cell metabolism.
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Affiliation(s)
- Pailin Chiaranunt
- Division of Blood and Marrow Transplant and Cellular Therapies, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, United States
| | - James L M Ferrara
- The Tisch Cancer Institute & Division of Hematology/Medical Oncology, Icahn School of Medicine, Hess Center for Science and Medicine, New York, NY 10029, United States
| | - Craig A Byersdorfer
- Division of Blood and Marrow Transplant and Cellular Therapies, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15224, United States.
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Giordano Attianese GMP, Desvergne B. Integrative and systemic approaches for evaluating PPARβ/δ (PPARD) function. NUCLEAR RECEPTOR SIGNALING 2015; 13:e001. [PMID: 25945080 PMCID: PMC4419664 DOI: 10.1621/nrs.13001] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 03/09/2015] [Indexed: 12/13/2022]
Abstract
The peroxisome proliferator-activated receptors (PPARs) are a group of nuclear receptors that function as transcription factors regulating the expression of genes involved in cellular differentiation, development, metabolism and also tumorigenesis. Three PPAR isotypes (α, β/δ and γ) have been identified, among which PPARβ/δ is the most difficult to functionally examine due to its tissue-specific diversity in cell fate determination, energy metabolism and housekeeping activities. PPARβ/δ acts both in a ligand-dependent and -independent manner. The specific type of regulation, activation or repression, is determined by many factors, among which the type of ligand, the presence/absence of PPARβ/δ-interacting corepressor or coactivator complexes and PPARβ/δ protein post-translational modifications play major roles. Recently, new global approaches to the study of nuclear receptors have made it possible to evaluate their molecular activity in a more systemic fashion, rather than deeply digging into a single pathway/function. This systemic approach is ideally suited for studying PPARβ/δ, due to its ubiquitous expression in various organs and its overlapping and tissue-specific transcriptomic signatures. The aim of the present review is to present in detail the diversity of PPARβ/δ function, focusing on the different information gained at the systemic level, and describing the global and unbiased approaches that combine a systems view with molecular understanding.
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37
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Kahremany S, Livne A, Gruzman A, Senderowitz H, Sasson S. Activation of PPARδ: from computer modelling to biological effects. Br J Pharmacol 2015; 172:754-70. [PMID: 25255770 PMCID: PMC4301687 DOI: 10.1111/bph.12950] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 09/13/2014] [Accepted: 09/18/2014] [Indexed: 12/18/2022] Open
Abstract
PPARδ is a ligand-activated receptor that dimerizes with another nuclear receptor of the retinoic acid receptor family. The dimers interact with other co-activator proteins and form active complexes that bind to PPAR response elements and promote transcription of genes involved in lipid metabolism. It appears that various natural fatty acids and their metabolites serve as endogenous activators of PPARδ; however, there is no consensus in the literature on the nature of the prime activators of the receptor. In vitro and cell-based assays of PPARδ activation by fatty acids and their derivatives often produce conflicting results. The search for synthetic and selective PPARδ agonists, which may be pharmacologically useful, is intense. Current rational modelling used to obtain such compounds relies mostly on crystal structures of synthetic PPARδ ligands with the recombinant ligand binding domain (LBD) of the receptor. Here, we introduce an original computational prediction model for ligand binding to PPARδ LBD. The model was built based on EC50 data of 16 ligands with available crystal structures and validated by calculating binding probabilities of 82 different natural and synthetic compounds from the literature. These compounds were independently tested in cell-free and cell-based assays for their capacity to bind or activate PPARδ, leading to prediction accuracy of between 70% and 93% (depending on ligand type). This new computational tool could therefore be used in the search for natural and synthetic agonists of the receptor.
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Affiliation(s)
- Shirin Kahremany
- Division of Medicinal Chemistry, Department of Chemistry, Faculty of Exact Sciences, Bar-Ilan UniversityRamat-Gan, Israel
| | - Ariela Livne
- Department of Pharmacology, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of JerusalemJerusalem, Israel
| | - Arie Gruzman
- Division of Medicinal Chemistry, Department of Chemistry, Faculty of Exact Sciences, Bar-Ilan UniversityRamat-Gan, Israel
| | - Hanoch Senderowitz
- Division of Medicinal Chemistry, Department of Chemistry, Faculty of Exact Sciences, Bar-Ilan UniversityRamat-Gan, Israel
| | - Shlomo Sasson
- Department of Pharmacology, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of JerusalemJerusalem, Israel
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Malm T, Mariani M, Donovan LJ, Neilson L, Landreth GE. Activation of the nuclear receptor PPARδ is neuroprotective in a transgenic mouse model of Alzheimer's disease through inhibition of inflammation. J Neuroinflammation 2015; 12:7. [PMID: 25592770 PMCID: PMC4310027 DOI: 10.1186/s12974-014-0229-9] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 12/21/2014] [Indexed: 12/23/2022] Open
Abstract
Background Alzheimer’s disease (AD) is a multifactorial disorder associated with the accumulation of soluble forms of beta-amyloid (Aβ) and its subsequent deposition into plaques. One of the major contributors to neuronal death is chronic and uncontrolled inflammatory activation of microglial cells around the plaques and their secretion of neurotoxic molecules. A shift in microglial activation towards a phagocytic phenotype has been proposed to confer benefit in models of AD. Peroxisome proliferator activator receptor δ (PPARδ) is a transcription factor with potent anti-inflammatory activation properties and PPARδ agonism leads to reduction in brain Aβ levels in 5XFAD mice. This study was carried out to elucidate the involvement of microglial activation in the PPARδ-mediated reduction of Aβ burden and subsequent outcome to neuronal survival in a 5XFAD mouse model of AD. Methods 5XFAD mice were orally treated with the PPARδ agonist GW0742 for 2 weeks. The brain Aβ load, glial activation, and neuronal survival were assessed by immunohistochemistry and quantitative PCR. In addition, the ability of GW0742 to prevent direct neuronal death as well as inflammation-induced neuron death was analyzed in vitro. Results Our results show for the first time that a short treatment period of 5XFAD mice was effective in reducing the parenchymal Aβ load without affecting the levels of intraneuronal Aβ. This was concomitant with a decrease in overall microglial activation and reduction in proinflammatory mediators. Instead, microglial immunoreactivity around Aβ deposits was increased. Importantly, the reduction in the proinflammatory milieu elicited by GW0742 treatment resulted in attenuation of neuronal loss in vivo in the subiculum of 5XFAD mice. In addition, whereas GW0742 failed to protect primary neurons against glutamate-induced cell death, it prevented inflammation-induced neuronal death in microglia-neuron co-cultures in vitro. Conclusions This study demonstrates that GW0742 treatment has a prominent anti-inflammatory effect in 5XFAD mice and suggests that PPARδ agonists may have therapeutic utility in treating AD.
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Affiliation(s)
- Tarja Malm
- Department of Neurosciences, Alzheimer Research Laboratory, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA. .,Department of Neurobiology, A.I.Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, 70211, Kuopio, Finland.
| | - Monica Mariani
- Department of Neurosciences, Alzheimer Research Laboratory, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA.
| | - Lauren J Donovan
- Department of Neurosciences, Alzheimer Research Laboratory, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA.
| | - Lee Neilson
- Department of Neurosciences, Alzheimer Research Laboratory, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA.
| | - Gary E Landreth
- Department of Neurosciences, Alzheimer Research Laboratory, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA.
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39
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Skerrett R, Malm T, Landreth G. Nuclear receptors in neurodegenerative diseases. Neurobiol Dis 2014; 72 Pt A:104-16. [PMID: 24874548 PMCID: PMC4246019 DOI: 10.1016/j.nbd.2014.05.019] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 05/14/2014] [Accepted: 05/17/2014] [Indexed: 01/04/2023] Open
Abstract
Nuclear receptors have generated substantial interest in the past decade as potential therapeutic targets for the treatment of neurodegenerative disorders. Despite years of effort, effective treatments for progressive neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, Huntington's disease and ALS remain elusive, making non-classical drug targets such as nuclear receptors an attractive alternative. A substantial literature in mouse models of disease and several clinical trials have investigated the role of nuclear receptors in various neurodegenerative disorders, most prominently AD. These studies have met with mixed results, yet the majority of studies in mouse models report positive outcomes. The mechanisms by which nuclear receptor agonists affect disease pathology remain unclear. Deciphering the complex signaling underlying nuclear receptor action in neurodegenerative diseases is essential for understanding this variability in preclinical studies, and for the successful translation of nuclear receptor agonists into clinical therapies.
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Affiliation(s)
- Rebecca Skerrett
- Department of Neurosciences, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA.
| | - Tarja Malm
- Department of Neurosciences, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA; A.I. Virtanen Institute for Molecular Sciences, Department of Neurobiology, University of Eastern Finland, Neulaniementie 2, 70211 Kuopio, Finland.
| | - Gary Landreth
- Department of Neurosciences, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA.
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Peppard JV, Rugg CA, Smicker MA, Powers E, Harnish E, Prisco J, Cirovic D, Wright PS, August PR, Chandross KJ. High-content phenotypic screening and triaging strategy to identify small molecules driving oligodendrocyte progenitor cell differentiation. ACTA ACUST UNITED AC 2014; 20:382-90. [PMID: 25394729 DOI: 10.1177/1087057114559490] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Multiple Sclerosis is a demyelinating disease of the CNS and the primary cause of neurological disability in young adults. Loss of myelinating oligodendrocytes leads to neuronal dysfunction and death and is an important contributing factor to this disease. Endogenous oligodendrocyte precursor cells (OPCs), which on differentiation are responsible for replacing myelin, are present in the adult CNS. As such, therapeutic agents that can stimulate OPCs to differentiate and remyelinate demyelinated axons under pathologic conditions may improve neuronal function and clinical outcome. We describe the details of an automated, cell-based, morphometric-based, high-content screen that is used to identify small molecules eliciting the differentiation of OPCs after 3 days. Primary screening was performed using rat CG-4 cells maintained in culture conditions that normally support a progenitor cell-like state. From a library of 73,000 diverse small molecules within the Sanofi collection, 342 compounds were identified that increased OPC morphological complexity as an indicator of oligodendrocyte maturation. Subsequent to the primary high-content screen, a suite of cellular assays was established that identified 22 nontoxic compounds that selectively stimulated primary rat OPCs but not C2C12 muscle cell differentiation. This rigorous triaging yielded several chemical series for further expansion and bio- or cheminformatics studies, and their compelling biological activity merits further investigation.
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Affiliation(s)
- Jane V Peppard
- Lead Generation & Candidate Realization, Sanofi Tucson Innovation Center, Tucson, AZ, USA
| | - Catherine A Rugg
- Lead Generation & Candidate Realization, Sanofi R&D, Bridgewater, NJ, USA
| | | | - Elaine Powers
- Lead Generation & Candidate Realization, Sanofi Tucson Innovation Center, Tucson, AZ, USA
| | - Erica Harnish
- Lead Generation & Candidate Realization, Sanofi Tucson Innovation Center, Tucson, AZ, USA
| | - Joy Prisco
- Lead Generation & Candidate Realization, Sanofi Tucson Innovation Center, Tucson, AZ, USA
| | - Dragan Cirovic
- Lead Generation & Candidate Realization, Sanofi Tucson Innovation Center, Tucson, AZ, USA
| | - Paul S Wright
- Lead Generation & Candidate Realization, Sanofi Tucson Innovation Center, Tucson, AZ, USA
| | - Paul R August
- Lead Generation & Candidate Realization, Sanofi Tucson Innovation Center, Tucson, AZ, USA
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41
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Neels JG, Grimaldi PA. Physiological functions of peroxisome proliferator-activated receptor β. Physiol Rev 2014; 94:795-858. [PMID: 24987006 DOI: 10.1152/physrev.00027.2013] [Citation(s) in RCA: 117] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The peroxisome proliferator-activated receptors, PPARα, PPARβ, and PPARγ, are a family of transcription factors activated by a diversity of molecules including fatty acids and fatty acid metabolites. PPARs regulate the transcription of a large variety of genes implicated in metabolism, inflammation, proliferation, and differentiation in different cell types. These transcriptional regulations involve both direct transactivation and interaction with other transcriptional regulatory pathways. The functions of PPARα and PPARγ have been extensively documented mainly because these isoforms are activated by molecules clinically used as hypolipidemic and antidiabetic compounds. The physiological functions of PPARβ remained for a while less investigated, but the finding that specific synthetic agonists exert beneficial actions in obese subjects uplifted the studies aimed to elucidate the roles of this PPAR isoform. Intensive work based on pharmacological and genetic approaches and on the use of both in vitro and in vivo models has considerably improved our knowledge on the physiological roles of PPARβ in various cell types. This review will summarize the accumulated evidence for the implication of PPARβ in the regulation of development, metabolism, and inflammation in several tissues, including skeletal muscle, heart, skin, and intestine. Some of these findings indicate that pharmacological activation of PPARβ could be envisioned as a therapeutic option for the correction of metabolic disorders and a variety of inflammatory conditions. However, other experimental data suggesting that activation of PPARβ could result in serious adverse effects, such as carcinogenesis and psoriasis, raise concerns about the clinical use of potent PPARβ agonists.
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Affiliation(s)
- Jaap G Neels
- Institut National de la Santé et de la Recherche Médicale U 1065, Mediterranean Center of Molecular Medicine (C3M), Team "Adaptive Responses to Immuno-metabolic Dysregulations," Nice, France; and Faculty of Medicine, University of Nice Sophia-Antipolis, Nice, France
| | - Paul A Grimaldi
- Institut National de la Santé et de la Recherche Médicale U 1065, Mediterranean Center of Molecular Medicine (C3M), Team "Adaptive Responses to Immuno-metabolic Dysregulations," Nice, France; and Faculty of Medicine, University of Nice Sophia-Antipolis, Nice, France
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42
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Szondy Z, Garabuczi E, Joós G, Tsay GJ, Sarang Z. Impaired clearance of apoptotic cells in chronic inflammatory diseases: therapeutic implications. Front Immunol 2014; 5:354. [PMID: 25136342 PMCID: PMC4117929 DOI: 10.3389/fimmu.2014.00354] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 07/09/2014] [Indexed: 12/14/2022] Open
Abstract
In healthy individuals, billions of cells die by apoptosis every day. Removal of the dead cells by phagocytosis (a process called efferocytosis) must be efficient to prevent secondary necrosis and the consequent release of pro-inflammatory cell contents that damages the tissue environment and provokes autoimmunity. In addition, detection and removal of apoptotic cells generally induces an anti-inflammatory response. As a consequence improper clearance of apoptotic cells, being the result of either genetic anomalies and/or a persistent disease state, contributes to the establishment and progression of a number of human chronic inflammatory diseases such as autoimmune and neurological disorders, inflammatory lung diseases, obesity, type 2 diabetes, or atherosclerosis. During the past decade, our knowledge about the mechanism of efferocytosis has significantly increased, providing therapeutic targets through which impaired phagocytosis of apoptotic cells and the consequent inflammation could be influenced in these diseases.
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Affiliation(s)
- Zsuzsa Szondy
- Department of Dental Biochemistry, Faculty of Dentistry, University of Debrecen , Debrecen , Hungary
| | - Eva Garabuczi
- Department of Dental Biochemistry, Faculty of Dentistry, University of Debrecen , Debrecen , Hungary
| | - Gergely Joós
- Department of Dental Biochemistry, Faculty of Dentistry, University of Debrecen , Debrecen , Hungary
| | - Gregory J Tsay
- Department of Internal Medicine, Faculty of Medicine, Chung Shan Medical University Hospital , Taichung , Taiwan
| | - Zsolt Sarang
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen , Debrecen , Hungary
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43
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Pan-PPAR modulation effectively protects APP/PS1 mice from amyloid deposition and cognitive deficits. Mol Neurobiol 2014; 51:661-71. [PMID: 24838579 PMCID: PMC4359287 DOI: 10.1007/s12035-014-8743-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 05/05/2014] [Indexed: 12/01/2022]
Abstract
Alzheimer’s disease (AD) is a neurodegenerative condition that leads to neuronal death and memory dysfunction. In the past, specific peroxisome proliferator-activated receptor (PPAR)γ-agonists, such as pioglitazone, have been tested with limited success to improve AD pathology. Here, we investigated the therapeutic efficacy of GFT1803, a novel potent PPAR agonist that activates all the three PPAR isoforms (α/δ/γ) in the APP/PS1 mouse model in comparison to the selective PPARγ-agonist pioglitazone. Both compounds showed similar brain/plasma partitioning ratios, although whole body and brain exposure to GFT1803 was significantly lower as compared to pioglitazone, at doses used in this study. Oral treatment of APP/PS1 mice with GFT1803 decreased microglial activation, amyloid β (Aβ) plaque area, Aβ levels in sodium dodecyl sulfate- and formic acid-soluble fractions in a concentration-dependent manner. With a single exception of Aβ38 and Aβ40 levels, measured by ELISA, these effects were not observed in mice treated with pioglitazone. Both ligands decreased glial fibrillary acidic protein (GFAP) expression to similar extent and did not affect ApoE expression. Finally, GFT1803 increased insulin-degrading enzyme expression. Analysis of spatial memory formation in the Morris water maze demonstrated that both compounds were able to partially revert the phenotype of APP/PS1 mice in comparison to wild-type mice with GFT1803 being most effective. As compared to pioglitazone, GFT1803 (pan-PPAR agonist) produced both quantitatively superior and qualitatively different therapeutic effects with respect to amyloid plaque burden, insoluble Aβ content, and neuroinflammation at significantly lower whole body and brain exposure rates.
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44
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Levin MC, Douglas JN, Meyers L, Lee S, Shin Y, Gardner LA. Neurodegeneration in multiple sclerosis involves multiple pathogenic mechanisms. Degener Neurol Neuromuscul Dis 2014; 4:49-63. [PMID: 32669900 PMCID: PMC7337253 DOI: 10.2147/dnnd.s54391] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 03/06/2014] [Indexed: 12/18/2022] Open
Abstract
Multiple sclerosis (MS) is a complex autoimmune disease that impairs the central nervous system (CNS). The neurological disability and clinical course of the disease is highly variable and unpredictable from one patient to another. The cause of MS is still unknown, but it is thought to occur in genetically susceptible individuals who develop disease due to a nongenetic trigger, such as altered metabolism, a virus, or other environmental factors. MS patients develop progressive, irreversible, neurological disability associated with neuronal and axonal damage, collectively known as neurodegeneration. Neurodegeneration was traditionally considered as a secondary phenomenon to inflammation and demyelination. However, recent data indicate that neurodegeneration develops along with inflammation and demyelination. Thus, MS is increasingly recognized as a neurodegenerative disease triggered by an inflammatory attack of the CNS. While both inflammation and demyelination are well described and understood cellular processes, neurodegeneration might be defined by a diverse pool of any of the following: neuronal cell death, apoptosis, necrosis, and virtual hypoxia. In this review, we present multiple theories and supporting evidence that identify common biological processes that contribute to neurodegeneration in MS.
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Affiliation(s)
- Michael C Levin
- Veterans Administration Medical Center.,Department of Neuroscience, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Joshua N Douglas
- Veterans Administration Medical Center.,Department of Neuroscience, University of Tennessee Health Science Center, Memphis, TN, USA
| | | | - Sangmin Lee
- Veterans Administration Medical Center.,Department of Neurology
| | - Yoojin Shin
- Veterans Administration Medical Center.,Department of Neurology
| | - Lidia A Gardner
- Veterans Administration Medical Center.,Department of Neurology
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Boullerne AI, Polak PE, Braun D, Sharp A, Pelligrino D, Feinstein DL. Effects of peptide fraction and counter ion on the development of clinical signs in experimental autoimmune encephalomyelitis. J Neurochem 2014; 129:696-703. [PMID: 24471474 DOI: 10.1111/jnc.12664] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Revised: 01/08/2014] [Accepted: 01/21/2014] [Indexed: 12/12/2022]
Abstract
The most commonly used immunogen to induce experimental autoimmune encephalomyelitis is MOG35-55 , a 21-residue peptide derived from myelin oligodendrocyte glycoprotein (MOG). In most studies, mice exhibit a chronic disease; however, in some studies mice show a transient disease. One variable that is not often controlled for is the peptide fraction of the purified MOG material, which can vary from less than 50% to over 90%, with the remainder of mass primarily comprised of the counter ion used for peptide purification. We compared the development of clinical signs in female C57Bl6 mice immunized with two commercially available MOG35-55 peptides of similar purity but different peptide fraction (MOG-A being 45%; MOG-B being 72%). A single immunization with MOG-A induced a chronic disease course with some recovery at later stages, whereas immunization with MOG-B induced a similar course of disease but with significantly lower average clinical scores despite a higher peptide content. The addition of a booster immunization significantly increased clinical severity with both preparations, and significantly reduced the average day of onset using MOG-A. To determine if the counter ion could influence disease, we compared MOG-B-containing trifluoroacetate with MOG-B-containing acetate. Although disease incidence and severity were similar, the average day of disease onset occurred approximately 5 days earlier with the use of MOG-B-containing trifluoroacetate. These results demonstrate that differences in peptide fraction influence the course of encephalomyelitis disease, which may be due in part to the levels of counter ions present in the purified material. These findings underscore the fact that a knowledge of peptide fraction is as critical as knowledge of peptide purity when using peptides from different sources.
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Affiliation(s)
- Anne I Boullerne
- Department of Anesthesiology, University of Illinois at Chicago, Chicago, Illinois, USA
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Gill N, Bijjem KRV, Sharma PL. Anti-inflammatory and anti-hyperalgesic effect of all-trans retinoic acid in carrageenan-induced paw edema in Wistar rats: involvement of peroxisome proliferator-activated receptor-β/δ receptors. Indian J Pharmacol 2014; 45:278-82. [PMID: 23833373 PMCID: PMC3696301 DOI: 10.4103/0253-7613.111944] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Revised: 10/20/2012] [Accepted: 02/27/2013] [Indexed: 11/18/2022] Open
Abstract
Objective: In this study, we investigated the role of peroxisome proliferator-activated receptors (PPAR)-β/δ receptors in carrageenan-induced inflammation and in the anti-inflammatory effects of all-trans retinoic acid (ATRA). Materials and Methods: The λ-carrageenan (0.1 ml of 1% w/v) was injected into intra-plantar (i.pl.) region of the hind paw to produce acute inflammation. Paw volume was measured by using the mercury plethysmography. Further, mechanical and thermal hyperalgesia (TH) were assessed by using the dynamic plantar aesthesiometer and plantar test apparatus, respectively. In addition, markers of oxido-nitrosative stress were assessed spectrophotometrically in the hind paw tissue 5 h post-carrageenan. Results: An i.pl injection of carrageenan has produced a marked mechanical hyperalgesia (MH) and TH in ipsilateral paw, which was associated with significant elevated oxido-nitrosative stress. Treatment with ATRA (5 mg/kg/p.o/4 days) and GW0742, a selective PPAR-β/δ receptor agonist (0.1 mg/kg/i.p/4 days), significantly decreased the paw volume, mechanical and TH as compared to vehicle control. Administration of GSK0660, selective PPAR-β/δ receptor antagonist, at a dose of (0.3 mg/kg/i.p/4 days), did not produce a significant effect on carrageenan-induced paw edema, MH and TH. However, co-administration of GSK0660 (0.3 mg/kg/i.p/4 days) along with both ATRA (5 mg/kg/p.o/4 days) and GW0742 (0.1 mg/kg/i.p/4 days), significantly reverse the decreased paw edema, MH, and TH. These observed ameliorative effects on inflammatory pain symptoms are correlated with the extent of reduction of oxido-nitrosative stress. Conclusion: From above findings, it can be concluded that ATRA exerts anti-inflammatory and anti-hyperalgesic effect, possibly through activation of PPAR-β/δ and subsequent reduction of oxido-nitrosative stress.
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Affiliation(s)
- Navneet Gill
- Department of Pharmacology, ISF College of Pharmacy, Moga, Punjab, India
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47
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Caruso C, Carniglia L, Durand D, Scimonelli TN, Lasaga M. Astrocytes: new targets of melanocortin 4 receptor actions. J Mol Endocrinol 2013; 51:R33-50. [PMID: 23881919 DOI: 10.1530/jme-13-0064] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Astrocytes exert a wide variety of functions with paramount importance in brain physiology. After injury or infection, astrocytes become reactive and they respond by producing a variety of inflammatory mediators that help maintain brain homeostasis. Loss of astrocyte functions as well as their excessive activation can contribute to disease processes; thus, it is important to modulate reactive astrocyte response. Melanocortins are peptides with well-recognized anti-inflammatory and neuroprotective activity. Although melanocortin efficacy was shown in systemic models of inflammatory disease, mechanisms involved in their effects have not yet been fully elucidated. Central anti-inflammatory effects of melanocortins and their mechanisms are even less well known, and, in particular, the effects of melanocortins in glial cells are poorly understood. Of the five known melanocortin receptors (MCRs), only subtype 4 is present in astrocytes. MC4R has been shown to mediate melanocortin effects on energy homeostasis, reproduction, inflammation, and neuroprotection and, recently, to modulate astrocyte functions. In this review, we will describe MC4R involvement in anti-inflammatory, anorexigenic, and anti-apoptotic effects of melanocortins in the brain. We will highlight MC4R action in astrocytes and discuss their possible mechanisms of action. Melanocortin effects on astrocytes provide a new means of treating inflammation, obesity, and neurodegeneration, making them attractive targets for therapeutic interventions in the CNS.
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Affiliation(s)
- Carla Caruso
- School of Medicine, Biomedical Research Institute (UBA-CONICET), University of Buenos Aires, Paraguay 2155 piso 10, 1121ABG Buenos Aires, Argentina IFEC (CONICET) Department of Pharmacology, School of Chemistry, National University of Córdoba, Córdoba, Argentina
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Promoting return of function in multiple sclerosis: An integrated approach. Mult Scler Relat Disord 2013; 2:S2211-0348(13)00044-8. [PMID: 24363985 DOI: 10.1016/j.msard.2013.04.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Multiple sclerosis is a disease characterized by inflammatory demyelination, axonal degeneration and progressive brain atrophy. Most of the currently available disease modifying agents proved to be very effective in managing the relapse rate, however progressive neuronal damage continues to occur and leads to progressive accumulation of irreversible disability. For this reason, any therapeutic strategy aimed at restoration of function must take into account not only immunomodulation, but also axonal protection and new myelin formation. We further highlight the importance of an holistic approach, which considers the variability of therapeutic responsiveness as the result of the interplay between genetic differences and the epigenome, which is in turn affected by gender, age and differences in life style including diet, exercise, smoking and social interaction.
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CCL5-glutamate interaction in central nervous system: Early and acute presynaptic defects in EAE mice. Neuropharmacology 2013; 75:337-46. [PMID: 23958452 DOI: 10.1016/j.neuropharm.2013.07.037] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Revised: 07/24/2013] [Accepted: 07/30/2013] [Indexed: 01/15/2023]
Abstract
We investigated the CCL5-glutamate interaction in the cortex and in the spinal cord from mice with Experimental Autoimmune Encephalomyelitis (EAE) at 13 and 21/30 days post immunization (d.p.i.), representing the onset and the peak of the disease, respectively. An early reduction of the KCl-evoked glutamate release was observed in cortical terminals from EAE mice at 13 d.p.i., persisting until 21/30 d.p.i. A concomitant reduction of the depolarization-evoked cyclic adenosine monophosphate (cAMP), but not of the inositol 1,4,5-trisphosphate (IP3) cortical production also occurred at 13 d.p.i, that still was detectable at the acute stage of disease (21 dp.i.). Inasmuch, the CCL5-mediated inhibition of glutamate exocytosis observed in control mice turned to facilitation in EAE mouse cortex at 13 d.p.i., then becoming undetectable at 21/30 d.p.i. Differently, glutamate exocytosis, as well as IP3 and cAMP productions were unaltered in spinal cord synaptosomes from EAE mice at 13 d.p.i., but significantly increased at 21/30 d.p.i., while the presynaptic CCL5-mediated facilitation of glutamate exocytosis observed in control mice remained unchanged. In both CNS regions, the presynaptic defects were parallelled by increased CCL5 availability. Inasmuch, the presynaptic defects so far described in EAE mice were reminiscent of the effects acute CCL5 exerts in control conditions. Based on these observations we propose that increased CCL5 bioavailability could have a role in determining the abovedescribed impaired presynaptic impairments in both CNS regions. These presynaptic defects could be relevant to the onset of early cognitive impairments and acute neuroinflammation and demyelinating processes observed in multiple sclerosis patients.
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α-Lipoic acid enhances endogenous peroxisome-proliferator-activated receptor-γ to ameliorate experimental autoimmune encephalomyelitis in mice. Clin Sci (Lond) 2013; 125:329-40. [PMID: 23550596 DOI: 10.1042/cs20120560] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
ALA (α-lipoic acid) is a natural, endogenous antioxidant that acts as a PPAR-γ (peroxisome-proliferator-activated receptor-γ) agonist to counteract oxidative stress. Thus far, the antioxidative and immunomodulatory effects of ALA on EAE (experimental autoimmune encephalomyelitis) are not well understood. In this study, we found that ALA restricts the infiltration of inflammatory cells into the CNS (central nervous system) in MOG (myelin oligodendrocyte glycoprotein)-EAE mice, thus reducing the disease severity. In addition, we revealed that ALA significantly suppresses the number and percentage of encephalitogenic Th1 and Th17 cells and increases splenic Treg-cells (regulatory T-cells). Strikingly, we further demonstrated that ALA induces endogenous PPAR-γ centrally and peripherally but has no effect on HO-1 (haem oxygenase 1). Together, these data suggest that ALA can up-regulate endogenous systemic and central PPAR-γ and enhance systemic Treg-cells to inhibit the inflammatory response and ameliorate MOG-EAE. In conclusion, our data provide the first evidence that ALA can augment the production of PPAR-γ in vivo and modulate adaptive immunity both centrally and peripherally in EAE and may reveal further antioxidative and immunomodulatory mechanisms for the application of ALA in human MS (multiple sclerosis).
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