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Lana D, Magni G, Landucci E, Wenk GL, Pellegrini-Giampietro DE, Giovannini MG. Phenomic Microglia Diversity as a Druggable Target in the Hippocampus in Neurodegenerative Diseases. Int J Mol Sci 2023; 24:13668. [PMID: 37761971 PMCID: PMC10531074 DOI: 10.3390/ijms241813668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 08/31/2023] [Accepted: 09/02/2023] [Indexed: 09/29/2023] Open
Abstract
Phenomics, the complexity of microglia phenotypes and their related functions compels the continuous study of microglia in disease animal models to find druggable targets for neurodegenerative disorders. Activation of microglia was long considered detrimental for neuron survival, but more recently it has become apparent that the real scenario of microglia morphofunctional diversity is far more complex. In this review, we discuss the recent literature on the alterations in microglia phenomics in the hippocampus of animal models of normal brain aging, acute neuroinflammation, ischemia, and neurodegenerative disorders, such as AD. Microglia undergo phenomic changes consisting of transcriptional, functional, and morphological changes that transform them into cells with different properties and functions. The classical subdivision of microglia into M1 and M2, two different, all-or-nothing states is too simplistic, and does not correspond to the variety of phenotypes recently discovered in the brain. We will discuss the phenomic modifications of microglia focusing not only on the differences in microglia reactivity in the diverse models of neurodegenerative disorders, but also among different areas of the brain. For instance, in contiguous and highly interconnected regions of the rat hippocampus, microglia show a differential, finely regulated, and region-specific reactivity, demonstrating that microglia responses are not uniform, but vary significantly from area to area in response to insults. It is of great interest to verify whether the differences in microglia reactivity may explain the differential susceptibility of different brain areas to insults, and particularly the higher sensitivity of CA1 pyramidal neurons to inflammatory stimuli. Understanding the spatiotemporal heterogeneity of microglia phenomics in health and disease is of paramount importance to find new druggable targets for the development of novel microglia-targeted therapies in different CNS disorders. This will allow interventions in three different ways: (i) by suppressing the pro-inflammatory properties of microglia to limit the deleterious effect of their activation; (ii) by modulating microglia phenotypic change to favor anti-inflammatory properties; (iii) by influencing microglia priming early in the disease process.
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Affiliation(s)
- Daniele Lana
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Viale Pieraccini 6, 50139 Florence, Italy; (E.L.); (D.E.P.-G.); (M.G.G.)
| | - Giada Magni
- Institute of Applied Physics “Nello Carrara”, National Research Council (IFAC-CNR), Via Madonna del Piano 10, 50019 Florence, Italy;
| | - Elisa Landucci
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Viale Pieraccini 6, 50139 Florence, Italy; (E.L.); (D.E.P.-G.); (M.G.G.)
| | - Gary L. Wenk
- Department of Psychology, The Ohio State University, Columbus, OH 43210, USA;
| | - Domenico Edoardo Pellegrini-Giampietro
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Viale Pieraccini 6, 50139 Florence, Italy; (E.L.); (D.E.P.-G.); (M.G.G.)
| | - Maria Grazia Giovannini
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Viale Pieraccini 6, 50139 Florence, Italy; (E.L.); (D.E.P.-G.); (M.G.G.)
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Jha NK, Sharma A, Jha SK, Ojha S, Chellappan DK, Gupta G, Kesari KK, Bhardwaj S, Shukla SD, Tambuwala MM, Ruokolainen J, Dua K, Singh SK. Alzheimer's disease-like perturbations in HIV-mediated neuronal dysfunctions: understanding mechanisms and developing therapeutic strategies. Open Biol 2020; 10:200286. [PMID: 33352062 PMCID: PMC7776571 DOI: 10.1098/rsob.200286] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 11/27/2020] [Indexed: 01/10/2023] Open
Abstract
Excessive exposure to toxic substances or chemicals in the environment and various pathogens, including viruses and bacteria, is associated with the onset of numerous brain abnormalities. Among them, pathogens, specifically viruses, elicit persistent inflammation that plays a major role in Alzheimer's disease (AD) as well as dementia. AD is the most common brain disorder that affects thought, speech, memory and ability to execute daily routines. It is also manifested by progressive synaptic impairment and neurodegeneration, which eventually leads to dementia following the accumulation of Aβ and hyperphosphorylated Tau. Numerous factors contribute to the pathogenesis of AD, including neuroinflammation associated with pathogens, and specifically viruses. The human immunodeficiency virus (HIV) is often linked with HIV-associated neurocognitive disorders (HAND) following permeation through the blood-brain barrier (BBB) and induction of persistent neuroinflammation. Further, HIV infections also exhibited the ability to modulate numerous AD-associated factors such as BBB regulators, members of stress-related pathways as well as the amyloid and Tau pathways that lead to the formation of amyloid plaques or neurofibrillary tangles accumulation. Studies regarding the role of HIV in HAND and AD are still in infancy, and potential link or mechanism between both is not yet established. Thus, in the present article, we attempt to discuss various molecular mechanisms that contribute to the basic understanding of the role of HIV-associated neuroinflammation in AD and HAND. Further, using numerous growth factors and drugs, we also present possible therapeutic strategies to curb the neuroinflammatory changes and its associated sequels.
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Affiliation(s)
- Niraj Kumar Jha
- Department of Biotechnology, School of Engineering and Technology (SET), Sharda University, Greater Noida, UP 201310, India
| | - Ankur Sharma
- Department of Life Science, School of Basic Science and Research (SBSR), Sharda University, Greater Noida, UP 201310, India
| | - Saurabh Kumar Jha
- Department of Biotechnology, School of Engineering and Technology (SET), Sharda University, Greater Noida, UP 201310, India
| | - Shreesh Ojha
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, PO Box 17666, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Dinesh Kumar Chellappan
- Department of Life Sciences, School of Pharmacy, International Medical University, Bukit Jalil, Kuala Lumpur 57000, Malaysia
| | - Gaurav Gupta
- School of Phamacy, Suresh Gyan Vihar University, Jagatpura, Mahal Road, Jaipur, India
| | - Kavindra Kumar Kesari
- Department of Applied Physics, School of Science, Aalto University, Espoo 00076, Finland
| | - Shanu Bhardwaj
- Department of Biotechnology, HIMT, Greater Noida, CCS University, UP, India
| | - Shakti D. Shukla
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute (HMRI) and School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Murtaza M. Tambuwala
- School of Pharmacy and Pharmaceutical Sciences, Ulster University, Coleraine, County Londonderry, BT52 1SA, UK
| | - Janne Ruokolainen
- Department of Applied Physics, School of Science, Aalto University, Espoo 00076, Finland
| | - Kamal Dua
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute (HMRI) and School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2308, Australia
- Discipline of Pharmacy, Graduate School of Health, University of Technology Sydney, Sydney, New South Wales 2007, Australia
- School of Pharmaceutical Sciences, Shoolini University of Biotechnology and Management Sciences, PO Box 9, Solan, Himachal Pradesh 173229, India
| | - Sandeep Kumar Singh
- Department of Biomedical Research, Centre of Biomedical Research, SGPGI Campus, Lucknow 226014, UP, India
- Biological Science, Indian Scientific Education and Technology Foundation, Lucknow 226002, UP, India
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3
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Thaney VE, Sanchez AB, Fields JA, Minassian A, Young JW, Maung R, Kaul M. Transgenic mice expressing HIV-1 envelope protein gp120 in the brain as an animal model in neuroAIDS research. J Neurovirol 2017; 24:156-167. [PMID: 29075998 DOI: 10.1007/s13365-017-0584-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 09/03/2017] [Accepted: 09/27/2017] [Indexed: 01/08/2023]
Abstract
HIV-1 infection causes injury to the central nervous system (CNS) and is often associated with neurocognitive disorders. One model for brain damage seen in AIDS patients is the transgenic (tg) mouse expressing a soluble envelope protein gp120 of HIV-1 LAV in the brain in astrocytes under the control of the promoter of glial fibrillary acidic protein. These GFAP-gp120tg mice manifest several key neuropathological features observed in AIDS brains, such as decreased synaptic and dendritic density, increased numbers of activated microglia, and pronounced astrocytosis. Several recent studies show that brains of GFAP-gp120tg mice and neurocognitively impaired HIV patients share also a significant number of differentially regulated genes, activation of innate immunity and other cellular signaling pathways, disturbed neurogenesis, and learning deficits. These findings support the continued relevance of the GFAP-gp120tg mouse as a useful model to investigate neurodegenerative mechanisms and develop therapeutic strategies to mitigate the consequences associated with HIV infection of the CNS, neuroAIDS, and HAND.
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Affiliation(s)
- Victoria E Thaney
- Infectious and Inflammatory Disease Center, Sanford Burnham Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Ana B Sanchez
- Infectious and Inflammatory Disease Center, Sanford Burnham Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Jerel A Fields
- Department of Psychiatry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - Arpi Minassian
- Department of Psychiatry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - Jared W Young
- Department of Psychiatry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - Ricky Maung
- Infectious and Inflammatory Disease Center, Sanford Burnham Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Marcus Kaul
- Infectious and Inflammatory Disease Center, Sanford Burnham Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, CA, 92037, USA. .,Department of Psychiatry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA. .,Division of Biomedical Sciences, School of Medicine, University of California, Riverside, 900 University Ave, Riverside, CA, 92521, USA.
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Abstract
Human immunodeficiency virus (HIV) infection induces neuronal injuries, with almost 50% of infected individuals developing HIV-associated neurocognitive disorders (HAND). Although highly activate antiretroviral therapy (HAART) has significantly reduced the incidence of severe dementia, the overall prevalence of HAND remains high. Synaptic degeneration is emerging as one of the most relevant neuropathologies associate with HAND. Previous studies have reported critical roles of viral proteins and inflammatory responses in this pathogenesis. Infected cells, including macrophages, microglia and astrocytes, may release viral proteins and other neurotoxins to stimulate neurons and cause excessive calcium influx, overproduction of free radicals and disruption of neurotransmitter hemostasis. The dysregulation of neural circuits likely leads to synaptic damage and loss. Identification of the specific mechanism of the synaptic degeneration may facilitate the development of effective therapeutic approaches to treat HAND.
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Affiliation(s)
- Wenjuan Ru
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX, 77555, USA
| | - Shao-Jun Tang
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX, 77555, USA.
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Gorantla S, Poluektova L, Gendelman HE. Rodent models for HIV-associated neurocognitive disorders. Trends Neurosci 2012; 35:197-208. [PMID: 22305769 DOI: 10.1016/j.tins.2011.12.006] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Revised: 12/16/2011] [Accepted: 12/19/2011] [Indexed: 11/28/2022]
Abstract
Human immunodeficiency virus (HIV)-associated neurocognitive disorders (HAND) reflect the spectrum of neural impairments seen during chronic viral infection. Current research efforts focus on improving antiretroviral and adjunctive therapies, defining disease onset and progression, facilitating drug delivery, and halting neurodegeneration and viral resistance. Because HIV is species-specific, generating disease in small-animal models has proved challenging. After two decades of research, rodent HAND models now include those containing a human immune system. Antiviral responses, neuroinflammation and immunocyte blood-brain barrier (BBB) trafficking follow HIV infection in these rodent models. We review these and other rodent models of HAND and discuss their unmet potential in reflecting human pathobiology and in facilitating disease monitoring and therapeutic discoveries.
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Affiliation(s)
- Santhi Gorantla
- Center for Neurodegenerative Disorders and Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, USA
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Genetic knockouts suggest a critical role for HIV co-receptors in models of HIV gp120-induced brain injury. J Neuroimmune Pharmacol 2011; 7:306-18. [PMID: 22124968 DOI: 10.1007/s11481-011-9328-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Accepted: 11/16/2011] [Indexed: 02/06/2023]
Abstract
Infection with HIV-1 frequently affects the brain and causes NeuroAIDS prior to the development of overt AIDS. The HIV-1 envelope protein gp120 interacts with host CD4 and chemokine co-receptors to initiate infection of macrophages and lymphocytes. In addition, the virus or fragments of it, such as gp120, cause macrophages to produce neurotoxins and trigger neuronal injury and apoptosis. Moreover, the two major HIV co-receptors, the chemokine receptors CCR5 and CXCR4, serve numerous physiological functions and are widely expressed beyond immune cells, including cells in the brain. Therefore, HIV co-receptors are poised to play a direct and indirect part in the development of NeuroAIDS. Although rodents are not permissive to infection with wild type HIV-1, viral co-receptors - more than CD4 - are highly conserved between species, suggesting the animals can be suitable models for mechanistic studies addressing effects of receptor-ligand interaction other than infection. Of note, transgenic mice expressing HIV gp120 in the brain share several pathological hallmarks with NeuroAIDS brains. Against this background, we will discuss recently completed or initiated, ongoing studies that utilize HIV co-receptor knockout and viral gp120-transgenic mice as models for in vitro and in vivo experimentation in order to address the potential roles of HIV gp120 and its co-receptors in the development of NeuroAIDS.
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7
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Human immunodeficiency virus type 1 infection increases the in vivo capacity of peripheral monocytes to cross the blood-brain barrier into the brain and the in vivo sensitivity of the blood-brain barrier to disruption by lipopolysaccharide. J Virol 2008; 82:7591-600. [PMID: 18508884 DOI: 10.1128/jvi.00768-08] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1), introduced into the brain by HIV-1-infected monocytes which migrate across the blood-brain barrier (BBB), infects resident macrophages and microglia and initiates a process that causes HIV-1-associated neurocognitive disorders. The mechanism by which HIV-1 infection circumvents the BBB-restricted passage of systemic leukocytes into the brain and disrupts the integrity of the BBB is not known. Circulating lipopolysaccharide (LPS), which can compromise the integrity of the BBB, is significantly increased in HIV-1-infected individuals. We hypothesized that HIV-1 infection increases monocyte capacity to migrate across the BBB, which is further facilitated by a compromise of BBB integrity mediated by the increased systemic LPS levels present in HIV-1-infected individuals. To investigate this possibility, we examined the in vivo BBB migration of monocytes derived from our novel mouse model, JR-CSF/EYFP mice, which are transgenic for both a long terminal repeat-regulated full-length infectious HIV-1 provirus and ROSA-26-regulated enhanced yellow fluorescent protein. We demonstrated that JR-CSF/EYFP mouse monocytes displayed an increased capacity to enter the brain by crossing either an intact BBB or a BBB whose integrity was partially compromised by systemic LPS. We also demonstrated that the JR-CSF mouse BBB was more susceptible to disruption by systemic LPS than the control wild-type mouse BBB. These results demonstrated that HIV-1 infection increased the ability of monocytes to enter the brain and increased the sensitivity of the BBB to disruption by systemic LPS, which is elevated in HIV-1-infected individuals. These mice represent a new in vivo system for studying the mechanism by which HIV-1-infected monocytes migrate into the brain.
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8
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Increased in vivo activation of microglia and astrocytes in the brains of mice transgenic for an infectious R5 human immunodeficiency virus type 1 provirus and for CD4-specific expression of human cyclin T1 in response to stimulation by lipopolysaccharides. J Virol 2008; 82:5562-72. [PMID: 18353948 DOI: 10.1128/jvi.02618-07] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Inflammatory mediators and viral products produced by human immunodeficiency virus (HIV)-infected microglia and astrocytes perturb the function and viability of adjacent uninfected neuronal and glial cells and contribute to the pathogenesis of HIV-associated neurocognitive disorders (HAND). In vivo exposure to lipopolysaccharide (LPS) activates parenchymal microglia and astrocytes and induces cytokine and chemokine production in the brain. HIV-infected individuals display increased circulating LPS levels due to microbial translocation across a compromised mucosa barrier. We hypothesized that HIV-infected microglia and astrocytes display increased sensitivity to the proinflammatory effects of LPS, and this combines with the increased levels of systemic LPS in HIV-infected individuals to contribute to the development of HAND. To examine this possibility, we determined the in vivo responsiveness of HIV-infected microglia and astrocytes to LPS using our mouse model, JR-CSF/human cyclin T1 (JR-CSF/hu-cycT1) mice, which are transgenic for both an integrated full-length infectious HIV type 1 (HIV-1) provirus derived from the primary R5-tropic clinical isolate HIV-1(JR-CSF) regulated by the endogenous HIV-1 long terminal repeat and the hu-cycT1 gene under the control of a CD4 promoter. In the current report, we demonstrated that in vivo-administered LPS more potently activated JR-CSF/hu-cycT1 mouse microglia and astrocytes and induced a significantly higher degree of monocyte chemoattractant protein production by JR-CSF/hu-cycT1 astrocytes compared to that of the in vivo LPS response of control littermate mouse microglia and astrocytes. These results indicate that HIV infection increases the sensitivity of microglia and astrocytes to inflammatory stimulation and support the use of these mice as a model to investigate various aspects of the in vivo mechanism of HIV-induced neuronal dysfunction.
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Nonprimate models of HIV-1 infection and pathogenesis. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2008; 56:399-422. [PMID: 18086419 DOI: 10.1016/s1054-3589(07)56013-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Karlen S, Zufferey R. Declassification of Rodents Exposed to Third-Generation HIV-Based Vectors into Class 1 Animals. APPLIED BIOSAFETY 2007. [DOI: 10.1177/153567600701200205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Stéphane Karlen
- Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland
| | - Romain Zufferey
- Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland
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11
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Peterson KE, Chesebro B. Influence of proinflammatory cytokines and chemokines on the neuropathogenesis of oncornavirus and immunosuppressive lentivirus infections. Curr Top Microbiol Immunol 2007; 303:67-95. [PMID: 16570857 DOI: 10.1007/978-3-540-33397-5_4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Retroviral infection of the CNS can lead to severe debilitating neurological diseases in humans and other animals. Four general types of pathogenic effects with various retroviruses have been observed including: hemorrhage (TR1.3), spongiform encephalopathy (CasBrE, FrCasE, PVC211, NT40, Mol-ts1), demyelination with inflammatory lesions (HTLV-1, visna, CAEV), and encephalopathy with gliosis and proinflammatory chemokines and cytokines, usually with microglial giant cells and nodules [human immunodeficiencyvirus (HIV), feline immunodeficiencyvirus (FIV), simian immunodeficiency virus (SIV), Fr98]. This review focuses on this fourth group of retroviruses. In this latter group, proinflammatory cytokine and chemokine upregulation accompanies the disease process, and may influence pathogenesis by direct effects on resident CNS cells. The review first discusses the Fr98 murine polytropic virus system with particular reference to the roles of cytokines and chemokines in the pathogenic process. The Fr98 data are then compared and contrasted to the cytokine and chemokine data in the lentivirus systems, HIV, SIV, and FIV. Finally, various mechanisms are presented by which tumor necrosis factor (TNF) and several chemokines may alter the pathogenesis of retrovirus infection of the CNS.
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Affiliation(s)
- K E Peterson
- Dept. of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA.
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12
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Neuroimmunity and the blood-brain barrier: molecular regulation of leukocyte transmigration and viral entry into the nervous system with a focus on neuroAIDS. J Neuroimmune Pharmacol 2006; 1:160-81. [PMID: 18040782 DOI: 10.1007/s11481-006-9017-3] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2005] [Accepted: 02/27/2006] [Indexed: 01/07/2023]
Abstract
HIV infection of the central nervous system (CNS) can result in neurologic dysfunction with devastating consequences in a significant number of individuals with AIDS. Two main CNS complications in individuals with HIV are encephalitis and dementia, which are characterized by leukocyte infiltration into the CNS, microglia activation, aberrant chemokine expression, blood-brain barrier (BBB) disruption, and eventual damage and/or loss of neurons. One of the major mediators of NeuroAIDS is the transmigration of HIV-infected leukocytes across the BBB into the CNS. This review summarizes new key findings that support a critical role of the BBB in regulating leukocyte transmigration. In addition, we discuss studies on communication among cells of the immune system, BBB, and the CNS parenchyma, and suggest how these interactions contribute to the pathogenesis of NeuroAIDS. We also describe some of the animal models that have been used to study and characterize important mechanisms that have been proposed to be involved in HIV-induced CNS dysfunction. Finally, we review the pharmacologic interventions that address neuroinflammation, and the effect of substance abuse on HIV-1 related neuroimmunity.
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Sun J, Soos T, Kewalramani VN, Osiecki K, Zheng JH, Falkin L, Santambrogio L, Littman DR, Goldstein H. CD4-specific transgenic expression of human cyclin T1 markedly increases human immunodeficiency virus type 1 (HIV-1) production by CD4+ T lymphocytes and myeloid cells in mice transgenic for a provirus encoding a monocyte-tropic HIV-1 isolate. J Virol 2006; 80:1850-62. [PMID: 16439541 PMCID: PMC1367149 DOI: 10.1128/jvi.80.4.1850-1862.2006] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1)-encoded Tat provides transcriptional activation critical for efficient HIV-1 replication by interacting with cyclin T1 and recruiting P-TEFb to efficiently elongate the nascent HIV transcript. Tat-mediated transcriptional activation in mice is precluded by species-specific structural differences that prevent Tat interaction with mouse cyclin T1 and severely compromise HIV-1 replication in mouse cells. We investigated whether transgenic mice expressing human cyclin T1 under the control of a murine CD4 promoter/enhancer cassette that directs gene expression to CD4(+) T lymphocytes and monocytes/macrophages (hu-cycT1 mice) would display Tat responsiveness in their CD4-expressing mouse cells and selectively increase HIV-1 production in this cellular population, which is infected primarily in HIV-1-positive individuals. To this end, we crossed hu-cycT1 mice with JR-CSF transgenic mice carrying the full-length HIV-1(JR-CSF) provirus under the control of the endogenous HIV-1 long terminal repeat and demonstrated that human cyclin T1 expression is sufficient to support Tat-mediated transactivation in primary mouse CD4 T lymphocytes and monocytes/macrophages and increases in vitro and in vivo HIV-1 production by these stimulated cells. Increased HIV-1 production by CD4(+) T lymphocytes was paralleled with their specific depletion in the peripheral blood of the JR-CSF/hu-cycT1 mice, which increased over time. In addition, increased HIV-1 transgene expression due to human cyclin T1 expression was associated with increased lipopolysaccharide-stimulated monocyte chemoattractant protein 1 production by JR-CSF mouse monocytes/macrophages in vitro. Therefore, the JR-CSF/hu-cycT1 mice should provide an improved mouse system for investigating the pathogenesis of various aspects of HIV-1-mediated disease and the efficacies of therapeutic interventions.
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Affiliation(s)
- Jinglin Sun
- Albert Einstein College of Medicine, Forschheimer Building, Room 408, 1300 Morris Park Avenue, Bronx, NY 10461, USA.
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Persidsky Y, Potula R, Haorah J. Rodent model systems for studies of HIV-1 associated dementia. Neurotox Res 2005; 8:91-106. [PMID: 16260388 DOI: 10.1007/bf03033822] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Understanding of HIV-1 neuropathogenesis and development of rationale therapeutic approaches requires relevant animal models. The putative mechanisms of neuroinflammatory and neurotoxic events triggered by HIV-1 brain infection are reflected by a number of rodent models. These include transgenic animals (either expressing viral proteins or pro-inflammatory factors), infection with murine retroviruses, and severe combined immunodeficient (SCID) mice reconstituted with human lymphocytes and injected intracerebrally with HIV-1-infected human monocyte-derived macrophages. The potential importance and limitations of the models in reflecting human disease are discussed with emphasis on their utility for development of therapies to combat HIV-1-associated neurologic impairment.
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Affiliation(s)
- Y Persidsky
- Center for Neurovirology and Neurodegenerative Disorders, University of Nebraska Medical Center, Omaha, NE 68198, USA.
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15
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D'Aversa TG, Eugenin EA, Berman JW. NeuroAIDS: Contributions of the human immunodeficiency virus-1 proteins tat and gp120 as well as CD40 to microglial activation. J Neurosci Res 2005; 81:436-46. [PMID: 15954144 DOI: 10.1002/jnr.20486] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Microglia are the resident phagocytes of the brain and are an important source of proinflammatory mediators. Human immunodeficiency virus (HIV)-1 infects the central nervous system early in the course of disease, and it is believed that this occurs, in part, through the transmigration of HIV-1-infected cells across the blood-brain barrier. Infected cells release viral proteins, such as Tat and gp120. After microglia interact with these proteins, they become activated and secrete chemokines; up-regulate key surface receptors, such as CD40, and also activate resident cells. This review focuses on the consequences of microglial activation in NeuroAIDS, with an emphasis on chemokine production and CD40 up-regulation after interaction with tat or gp120. The importance of microglial CD40 in two other neurological diseases, Alzheimer's disease and multiple sclerosis, is also discussed.
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Affiliation(s)
- T G D'Aversa
- Department of Pathology, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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Báfica A, Scanga CA, Schito M, Chaussabel D, Sher A. Influence of Coinfecting Pathogens on HIV Expression: Evidence for a Role of Toll-Like Receptors. THE JOURNAL OF IMMUNOLOGY 2004; 172:7229-34. [PMID: 15187096 DOI: 10.4049/jimmunol.172.12.7229] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Immune activation of HIV gene expression as a consequence of the host response to coinfecting pathogens has been implicated as an important factor in AIDS progression. Immune responsiveness to many of the infectious agents associated with HIV has been demonstrated to depend on a family of innate recognition molecules, known as Toll-like receptors (TLR). Therefore, TLR-pathogen interactions could play an indirect role in regulating HIV-associated disease. In this review, we summarize emerging evidence for the influence of TLR recognition on HIV gene activation and AIDS progression.
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Affiliation(s)
- André Báfica
- Immunobiology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Building 50, Rm. 6146, 50 South Drive, Bethesda, MD 20892, USA.
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Dou H, Kingsley JD, Mosley RL, Gelbard HA, Gendelman HE. Neuroprotective strategies for HIV-1 associated dementia. Neurotox Res 2004; 6:503-21. [PMID: 15639783 DOI: 10.1007/bf03033447] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The human immunodeficiency virus-1 (HIV-1) commonly affects cognitive, behavioral and motor functions during the disease course. The neuropathogenesis of viral infection revolves around neurotoxins produced from infected and immune-activated mononuclear phagocytes (MP; perivascular macrophages and microglia). Direct infection of neurons occurs rarely, if at all. Neurologic disease arises in part as a consequence of MP metabolic dysfunction. Although the advent of highly active antiretroviral therapy (HAART) has attenuated the incidence and severity of neurologic disease, it, nonetheless, remains a common and disabling problem for those living with HIV-1 infection. Adjunctive therapies are currently designed to ameliorate clinical outcomes and are included in the therapeutic armamentarium. Anti-inflammatory drugs that inhibit cytokines, chemokines and interferons linked to neurodegenerative processes can significantly ameliorate neuronal function. HIV-1 neurotoxins have the unique ability to up-regulate glycogen synthase kinase-3beta (GSK-3beta) activity that in turn elicits neuronal apoptosis. GSK-3beta inhibitors are neuroprotective in animal models of Neuro AIDS. They are also currently in Phase 1 clinical trials designed for safety and tolerability in patients with HIV-1 infection. Neurotrophins are only beginning to be realized for their therapeutic potential in HIV-1 associated neurologic disease. This review article provides a broad overview of neuroprotective strategies for HIV-1 infection and details how such strategies act and may be implemented for treatment of human disease.
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Affiliation(s)
- Huanyu Dou
- Center for Neurovirology and Neurodegenerative Disorders, Department of Pharmacology, University of Nebraska Medical Center, Omaha, NE 68198-5215, USA
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