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Vanegas-Torres CA, Schindler M. HIV-1 Vpr Functions in Primary CD4 + T Cells. Viruses 2024; 16:420. [PMID: 38543785 PMCID: PMC10975730 DOI: 10.3390/v16030420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 03/05/2024] [Accepted: 03/05/2024] [Indexed: 05/23/2024] Open
Abstract
HIV-1 encodes four accesory proteins in addition to its structural and regulatory genes. Uniquely amongst them, Vpr is abundantly present within virions, meaning it is poised to exert various biological effects on the host cell upon delivery. In this way, Vpr contributes towards the establishment of a successful infection, as evidenced by the extent to which HIV-1 depends on this factor to achieve full pathogenicity in vivo. Although HIV infects various cell types in the host organism, CD4+ T cells are preferentially targeted since they are highly permissive towards productive infection, concomitantly bringing about the hallmark immune dysfunction that accompanies HIV-1 spread. The last several decades have seen unprecedented progress in unraveling the activities Vpr possesses in the host cell at the molecular scale, increasingly underscoring the importance of this viral component. Nevertheless, it remains controversial whether some of these advances bear in vivo relevance, since commonly employed cellular models significantly differ from primary T lymphocytes. One prominent example is the "established" ability of Vpr to induce G2 cell cycle arrest, with enigmatic physiological relevance in infected primary T lymphocytes. The objective of this review is to present these discoveries in their biological context to illustrate the mechanisms whereby Vpr supports HIV-1 infection in CD4+ T cells, whilst identifying findings that require validation in physiologically relevant models.
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Affiliation(s)
| | - Michael Schindler
- Institute for Medical Virology and Epidemiology of Viral Diseases, University Hospital Tuebingen, 72076 Tuebingen, Germany;
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2
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Moss EM, Mahdi F, Worth CJ, Paris JJ. Physiological Corticosterone Attenuates gp120-Mediated Microglial Activation and Is Associated with Reduced Anxiety-Like Behavior in gp120-Expressing Mice. Viruses 2023; 15:v15020424. [PMID: 36851638 PMCID: PMC9965171 DOI: 10.3390/v15020424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/17/2023] [Accepted: 01/29/2023] [Indexed: 02/05/2023] Open
Abstract
Despite the benefits of combinatorial antiretroviral therapies (cART), virotoxic HIV proteins are still detectable within the central nervous system. Approximately half of all cART-treated patients contend with neurological impairments. The mechanisms underlying these effects likely involve virotoxic HIV proteins, including glycoprotein 120 (gp120). Glycoprotein-120 is neurotoxic due to its capacity to activate microglia. Corticosterone has been found to attenuate neuronal death caused by gp120-induced microglial cytokine production in vitro. However, the concentration-dependent effects of corticosterone on microglial activation states and the associated behavioral outcomes are unclear. Herein, we conducted parallel in vitro and in vivo studies to assess gp120-mediated effects on microglial activation, motor function, anxiety- and depression-like behavior, and corticosterone's capacity to attenuate these effects. We found that gp120 activated microglia in vitro, and corticosterone attenuated this effect at an optimal concentration of 100 nM. Transgenic mice expressing gp120 demonstrated greater anxiety-like behavior on an elevated plus maze, and a greater duration of gp120 exposure was associated with motor deficits and anxiety-like behavior. Circulating corticosterone was lower in gp120-expressing males and diestrous females. Greater circulating corticosterone was associated with reduced anxiety-like behavior. These findings may demonstrate a capacity for glucocorticoids to attenuate gp120-mediated neuroinflammation and anxiety-like behavior.
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Affiliation(s)
- Emaya M. Moss
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, University, MS 38677-1848, USA
| | - Fakhri Mahdi
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, University, MS 38677-1848, USA
| | - Charlie J. Worth
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, University, MS 38677-1848, USA
| | - Jason J. Paris
- Department of BioMolecular Sciences, School of Pharmacy, University of Mississippi, University, MS 38677-1848, USA
- Research Institute of Pharmaceutical Sciences, University of Mississippi, University, MS 38677-1848, USA
- Correspondence: ; Tel.: +1-662-915-3096
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3
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Shrivastav S, Lee H, Okamoto K, Lu H, Yoshida T, Latt KZ, Wakashin H, Dalgleish JLT, Koritzinsky EH, Xu P, Asico LD, Chung JY, Hewitt S, Gildea JJ, Felder RA, Jose PA, Rosenberg AZ, Knepper MA, Kino T, Kopp JB. HIV-1 Vpr suppresses expression of the thiazide-sensitive sodium chloride co-transporter in the distal convoluted tubule. PLoS One 2022; 17:e0273313. [PMID: 36129874 PMCID: PMC9491550 DOI: 10.1371/journal.pone.0273313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 08/07/2022] [Indexed: 11/19/2022] Open
Abstract
HIV-associated nephropathy (HIVAN) impairs functions of both glomeruli and tubules. Attention has been previously focused on the HIVAN glomerulopathy. Tubular injury has drawn increased attention because sodium wasting is common in hospitalized HIV/AIDS patients. We used viral protein R (Vpr)-transgenic mice to investigate the mechanisms whereby Vpr contributes to urinary sodium wasting. In phosphoenolpyruvate carboxykinase promoter-driven Vpr-transgenic mice, in situ hybridization showed that Vpr mRNA was expressed in all nephron segments, including the distal convoluted tubule. Vpr-transgenic mice, compared with wild-type littermates, markedly increased urinary sodium excretion, despite similar plasma renin activity and aldosterone levels. Kidneys from Vpr-transgenic mice also markedly reduced protein abundance of the Na+-Cl- cotransporter (NCC), while mineralocorticoid receptor (MR) protein expression level was unchanged. In African green monkey kidney cells, Vpr abrogated the aldosterone-mediated stimulation of MR transcriptional activity. Gene expression of Slc12a3 (NCC) in Vpr-transgenic mice was significantly lower compared with wild-type mice, assessed by both qRT-PCR and RNAScope in situ hybridization analysis. Chromatin immunoprecipitation assays identified multiple MR response elements (MRE), located from 5 kb upstream of the transcription start site and extending to the third exon of the SLC12A3 gene. Mutation of MRE and SP1 sites in the SLC12A3 promoter region abrogated the transcriptional responses to aldosterone and Vpr, indicating that functional MRE and SP1 are required for the SLC12A3 gene suppression in response to Vpr. Thus, Vpr attenuates MR transcriptional activity and inhibits Slc12a3 transcription in the distal convoluted tubule and contributes to salt wasting in Vpr-transgenic mice.
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Affiliation(s)
- Shashi Shrivastav
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - Hewang Lee
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
- Department of Medicine, The George Washington University School of Medicine & Health Sciences, Washington, DC, United States of America
| | - Koji Okamoto
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - Huiyan Lu
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - Teruhiko Yoshida
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - Khun Zaw Latt
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - Hidefumi Wakashin
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - James L. T. Dalgleish
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - Erik H. Koritzinsky
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
| | - Peng Xu
- Department of Pathology, University of Virginia, Charlottesville, Virginia, United States of America
| | - Laureano D. Asico
- Department of Medicine, The George Washington University School of Medicine & Health Sciences, Washington, DC, United States of America
| | - Joon-Yong Chung
- Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, NCI, NIH, Bethesda, Maryland, United States of America
| | - Stephen Hewitt
- Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, NCI, NIH, Bethesda, Maryland, United States of America
| | - John J. Gildea
- Department of Pathology, University of Virginia, Charlottesville, Virginia, United States of America
| | - Robin A. Felder
- Department of Pathology, University of Virginia, Charlottesville, Virginia, United States of America
| | - Pedro A. Jose
- Department of Medicine, The George Washington University School of Medicine & Health Sciences, Washington, DC, United States of America
| | - Avi Z. Rosenberg
- Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland, United States of America
| | - Mark A. Knepper
- Epithelial Systems Biology Laboratory, Systems Biology Center, Division of Intramural Research, NHLBI, NIH, Bethesda, Maryland, United States of America
| | - Tomoshige Kino
- Laboratory for Molecular and Genomic Endocrinology, Division of Translational Medicine, Sidra Medicine, Doha, Qatar
| | - Jeffrey B. Kopp
- Kidney Disease Section, Kidney Diseases Branch, NIDDK, NIH, Bethesda, Maryland, United States of America
- * E-mail:
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4
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Salahuddin MF, Qrareya AN, Mahdi F, Moss E, Akins NS, Li J, Le HV, Paris JJ. Allopregnanolone and neuroHIV: Potential benefits of neuroendocrine modulation in the era of antiretroviral therapy. J Neuroendocrinol 2022; 34:e13047. [PMID: 34651359 PMCID: PMC8866218 DOI: 10.1111/jne.13047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 09/24/2021] [Accepted: 09/28/2021] [Indexed: 12/12/2022]
Abstract
Forty years into the HIV pandemic, approximately 50% of infected individuals still suffer from a constellation of neurological disorders collectively known as 'neuroHIV.' Although combination antiretroviral therapy (cART) has been a tremendous success, in its present form, it cannot eradicate HIV. Reservoirs of virus reside within the central nervous system, serving as sources of HIV virotoxins that damage mitochondria and promote neurotoxicity. Although understudied, there is evidence that HIV or the HIV regulatory protein, trans-activator of transcription (Tat), can dysregulate neurosteroid formation potentially contributing to endocrine dysfunction. People living with HIV commonly suffer from endocrine disorders, including hypercortisolemia accompanied by paradoxical adrenal insufficiency upon stress. Age-related comorbidities often onset sooner and with greater magnitude among people living with HIV and are commonly accompanied by hypogonadism. In the post-cART era, these derangements of the hypothalamic-pituitary-adrenal and -gonadal axes are secondary (i.e., relegated to the brain) and indicative of neuroendocrine dysfunction. We review the clinical and preclinical evidence for neuroendocrine dysfunction in HIV, the capacity for hormone therapeutics to play an ameliorative role and the future steroid-based therapeutics that may have efficacy as novel adjunctives to cART.
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Affiliation(s)
- Mohammed F. Salahuddin
- Department of BioMolecular SciencesSchool of PharmacyUniversity of MississippiUniversityMSUSA
| | - Alaa N. Qrareya
- Department of BioMolecular SciencesSchool of PharmacyUniversity of MississippiUniversityMSUSA
| | - Fakhri Mahdi
- Department of BioMolecular SciencesSchool of PharmacyUniversity of MississippiUniversityMSUSA
| | - Emaya Moss
- Department of BioMolecular SciencesSchool of PharmacyUniversity of MississippiUniversityMSUSA
| | - Nicholas S. Akins
- Department of BioMolecular SciencesSchool of PharmacyUniversity of MississippiUniversityMSUSA
| | - Jing Li
- Department of BioMolecular SciencesSchool of PharmacyUniversity of MississippiUniversityMSUSA
- Research Institute of Pharmaceutical SciencesSchool of PharmacyUniversity of MississippiUniversityMSUSA
| | - Hoang V. Le
- Department of BioMolecular SciencesSchool of PharmacyUniversity of MississippiUniversityMSUSA
- Research Institute of Pharmaceutical SciencesSchool of PharmacyUniversity of MississippiUniversityMSUSA
| | - Jason J. Paris
- Department of BioMolecular SciencesSchool of PharmacyUniversity of MississippiUniversityMSUSA
- Research Institute of Pharmaceutical SciencesSchool of PharmacyUniversity of MississippiUniversityMSUSA
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5
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Structure of HIV-1 Vpr in complex with the human nucleotide excision repair protein hHR23A. Nat Commun 2021; 12:6864. [PMID: 34824204 PMCID: PMC8617076 DOI: 10.1038/s41467-021-27009-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 10/26/2021] [Indexed: 11/25/2022] Open
Abstract
HIV-1 Vpr is a prototypic member of a large family of structurally related lentiviral virulence factors that antagonize various aspects of innate antiviral immunity. It subverts host cell DNA repair and protein degradation machineries by binding and inhibiting specific post-replication repair enzymes, linking them via the DCAF1 substrate adaptor to the Cullin 4 RING E3 ligase (CRL4DCAF1). HIV-1 Vpr also binds to the multi-domain protein hHR23A, which interacts with the nucleotide excision repair protein XPC and shuttles ubiquitinated proteins to the proteasome. Here, we report the atomic resolution structure of Vpr in complex with the C-terminal half of hHR23A, containing the XPC-binding (XPCB) and ubiquitin-associated (UBA2) domains. The XPCB and UBA2 domains bind to different sides of Vpr's 3-helix-bundle structure, with UBA2 interacting with the α2 and α3 helices of Vpr, while the XPCB domain contacts the opposite side of Vpr's α3 helix. The structure as well as biochemical results reveal that hHR23A and DCAF1 use overlapping binding surfaces on Vpr, even though the two proteins exhibit entirely different three-dimensional structures. Our findings show that Vpr independently targets hHR23A- and DCAF1- dependent pathways and highlight HIV-1 Vpr as a versatile module that interferes with DNA repair and protein degradation pathways.
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6
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Kino T, Burd I, Segars JH. Dexamethasone for Severe COVID-19: How Does It Work at Cellular and Molecular Levels? Int J Mol Sci 2021; 22:ijms22136764. [PMID: 34201797 PMCID: PMC8269070 DOI: 10.3390/ijms22136764] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/10/2021] [Accepted: 06/18/2021] [Indexed: 12/12/2022] Open
Abstract
The coronavirus disease 2019 (COVID-19) caused by infection of the severe respiratory syndrome coronavirus-2 (SARS-CoV-2) significantly impacted human society. Recently, the synthetic pure glucocorticoid dexamethasone was identified as an effective compound for treatment of severe COVID-19. However, glucocorticoids are generally harmful for infectious diseases, such as bacterial sepsis and severe influenza pneumonia, which can develop respiratory failure and systemic inflammation similar to COVID-19. This apparent inconsistency suggests the presence of pathologic mechanism(s) unique to COVID-19 that renders this steroid effective. We review plausible mechanisms and advance the hypothesis that SARS-CoV-2 infection is accompanied by infected cell-specific glucocorticoid insensitivity as reported for some other viruses. This alteration in local glucocorticoid actions interferes with undesired glucocorticoid to facilitate viral replication but does not affect desired anti-inflammatory properties in non-infected organs/tissues. We postulate that the virus coincidentally causes glucocorticoid insensitivity in the process of modulating host cell activities for promoting its replication in infected cells. We explore this tenet focusing on SARS-CoV-2-encoding proteins and potential molecular mechanisms supporting this hypothetical glucocorticoid insensitivity unique to COVID-19 but not characteristic of other life-threatening viral diseases, probably due to a difference in specific virally-encoded molecules and host cell activities modulated by them.
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Affiliation(s)
- Tomoshige Kino
- Laboratory of Molecular and Genomic Endocrinology, Sidra Medicine, Doha 26999, Qatar
- Correspondence: ; Tel.: +974-4003-7566
| | - Irina Burd
- Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; (I.B.); (J.H.S.)
| | - James H. Segars
- Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; (I.B.); (J.H.S.)
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O'Brien MJ, Ansari A. Critical Involvement of TFIIB in Viral Pathogenesis. Front Mol Biosci 2021; 8:669044. [PMID: 33996913 PMCID: PMC8119876 DOI: 10.3389/fmolb.2021.669044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 04/08/2021] [Indexed: 11/23/2022] Open
Abstract
Viral infections and the harm they cause to their host are a perpetual threat to living organisms. Pathogenesis and subsequent spread of infection requires replication of the viral genome and expression of structural and non-structural proteins of the virus. Generally, viruses use transcription and translation machinery of the host cell to achieve this objective. The viral genome encodes transcriptional regulators that alter the expression of viral and host genes by manipulating initiation and termination steps of transcription. The regulation of the initiation step is often through interactions of viral factors with gene specific factors as well as general transcription factors (GTFs). Among the GTFs, TFIIB (Transcription Factor IIB) is a frequent target during viral pathogenesis. TFIIB is utilized by a plethora of viruses including human immunodeficiency virus, herpes simplex virus, vaccinia virus, Thogoto virus, hepatitis virus, Epstein-Barr virus and gammaherpesviruses to alter gene expression. A number of viral transcriptional regulators exhibit a direct interaction with host TFIIB in order to accomplish expression of their genes and to repress host transcription. Some viruses have evolved proteins with a three-dimensional structure very similar to TFIIB, demonstrating the importance of TFIIB for viral persistence. Upon viral infection, host transcription is selectively altered with viral transcription benefitting. The nature of viral utilization of TFIIB for expression of its own genes, along with selective repression of host antiviral genes and downregulation of general host transcription, makes TFIIB a potential candidate for antiviral therapies.
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Affiliation(s)
- Michael J O'Brien
- Department of Biological Science, Wayne State University, Detroit, MI, United States
| | - Athar Ansari
- Department of Biological Science, Wayne State University, Detroit, MI, United States
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HIV-1 Tat Protein Promotes Neuroendocrine Dysfunction Concurrent with the Potentiation of Oxycodone's Psychomotor Effects in Female Mice. Viruses 2021; 13:v13050813. [PMID: 33946474 PMCID: PMC8147167 DOI: 10.3390/v13050813] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 04/23/2021] [Accepted: 04/27/2021] [Indexed: 02/06/2023] Open
Abstract
Human immunodeficiency virus (HIV) is associated with neuroendocrine dysfunction which may contribute to co-morbid stress-sensitive disorders. The hypothalamic-pituitary-adrenal (HPA) or -gonadal (HPG) axes are perturbed in up to 50% of HIV patients. The mechanisms are not known, but we have found the HIV-1 trans-activator of transcription (Tat) protein to recapitulate the clinical phenotype in male mice. We hypothesized that HPA and/or HPG dysregulation contributes to Tat-mediated interactions with oxycodone, an opioid often prescribed to HIV patients, in females. Female mice that conditionally-expressed the Tat1-86 protein [Tat(+) mice] or their counterparts that did not [Tat(-) control mice] were exposed to forced swim stress (or not) and behaviorally-assessed for motor and anxiety-like behavior. Some mice had glucocorticoid receptors (GR) or corticotropin-releasing factor receptors (CRF-R) pharmacologically inhibited. Some mice were ovariectomized (OVX). As seen previously in males, Tat elevated basal corticosterone levels and potentiated oxycodone's psychomotor activity in females. Unlike males, females did not demonstrate adrenal insufficiency and oxycodone potentiation was not regulated by GRs or CRF-Rs. Rather OVX attenuated Tat/oxycodone interactions. Either Tat or oxycodone increased anxiety-like behavior and their combination increased hypothalamic allopregnanolone. OVX increased basal hypothalamic allopregnanolone and obviated Tat or oxycodone-mediated fluctuations. Together, these data provide further evidence for Tat-mediated dysregulation of the HPA axis and reveal the importance of HPG axis regulation in females. HPA/HPG disruption may contribute vulnerability to affective and substance use disorders.
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HIV-1 Tat Dysregulates the Hypothalamic-Pituitary-Adrenal Stress Axis and Potentiates Oxycodone-Mediated Psychomotor and Anxiety-Like Behavior of Male Mice. Int J Mol Sci 2020; 21:ijms21218212. [PMID: 33153023 PMCID: PMC7662349 DOI: 10.3390/ijms21218212] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 10/28/2020] [Accepted: 10/30/2020] [Indexed: 01/31/2023] Open
Abstract
Human immunodeficiency virus (HIV) is associated with co-morbid affective and stress-sensitive neuropsychiatric disorders that may be related to dysfunction of the hypothalamic-pituitary-adrenal (HPA) stress axis. The HPA axis is perturbed in up to 46% of HIV patients, but the mechanisms are not known. The neurotoxic HIV-1 regulatory protein, trans-activator of transcription (Tat), may contribute. We hypothesized that HPA dysregulation may contribute to Tat-mediated interactions with oxycodone, a clinically-used opioid often prescribed to HIV patients. In transgenic male mice, Tat expression produced significantly higher basal corticosterone levels with adrenal insufficiency in response to a natural stressor or pharmacological blockade of HPA feedback, recapitulating the clinical phenotype. On acute exposure, HIV-1 Tat interacted with oxycodone to potentiate psychomotor and anxiety like-behavior in an open field and light-dark transition tasks, whereas repeated exposure sensitized stress-related psychomotor behavior and the HPA stress response. Pharmacological blockade of glucocorticoid receptors (GR) partially-restored the stress response and decreased oxycodone-mediated psychomotor behavior in Tat-expressing mice, implicating GR in these effects. Blocking corticotrophin-releasing factor (CRF) receptors reduced anxiety-like behavior in mice that were exposed to oxycodone. Together, these effects support the notion that Tat exposure can dysregulate the HPA axis, potentially raising vulnerability to stress-related substance use and affective disorders.
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10
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Schmitt K, Curlin J, Remling-Mulder L, Moriarty R, Goff K, O'Connor S, Stenglein M, Marx P, Akkina R. Cross-Species Transmission and Evolution of SIV Chimpanzee Progenitor Viruses Toward HIV-1 in Humanized Mice. Front Microbiol 2020; 11:1889. [PMID: 32849468 PMCID: PMC7432304 DOI: 10.3389/fmicb.2020.01889] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 07/20/2020] [Indexed: 12/22/2022] Open
Abstract
The genetic evolution of HIV-1 from its progenitor virus SIV following cross-species transmission is not well understood. Here we simulated the SIVcpz initial transmission to humans using humanized mice and followed the viral evolution during serial passages lasting more than a year. All three SIVcpz progenitor viruses used, namely LB715 and MB897 (group M) as well as EK505 (group N) readily infected hu-mice resulting in chronic viremia. Viral loads increased progressively to higher set-points and the CD4+ T cell decline became more pronounced by the end of the second serial passage indicating viral adaptation and increased pathogenicity. Viral genomes sequenced at different time points revealed many non-synonymous variants not previously reported that occurred throughout the viral genome, including the gag, pol, env, and nef genes. These results shed light on the potential changes that the SIVcpz genome had undergone during the initial stages of human infection and subsequent spread.
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Affiliation(s)
- Kimberly Schmitt
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - James Curlin
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Leila Remling-Mulder
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Ryan Moriarty
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, WI, United States
| | - Kelly Goff
- Tulane National Primate Research Center, Tulane University, Covington, LA, United States
| | - Shelby O'Connor
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, WI, United States
| | - Mark Stenglein
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Preston Marx
- Tulane National Primate Research Center, Tulane University, Covington, LA, United States.,Department of Tropical Medicine, School of Public Health & Tropical Medicine, Tulane University, New Orleans, LA, United States
| | - Ramesh Akkina
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
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11
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Womersley JS, Clauss LB, Varathan O, Engelbrecht S, Hemmings SMJ, Seedat S, Spies G. The effect of childhood trauma, ApoE genotype and HIV-1 viral protein R variants on change in cognitive performance. BMC Res Notes 2019; 12:828. [PMID: 31881924 PMCID: PMC6935155 DOI: 10.1186/s13104-019-4869-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 12/19/2019] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE Gene-environment interactions contribute to the development of HIV-associated neurocognitive disorders. We examined whether childhood trauma, apolipoprotein E isoforms and viral protein R (Vpr) variants were associated with change in cognitive performance. Seventy-three seropositive women completed neuropsychological assessments at baseline and 1-year follow-up. We conducted genetic analyses using DNA obtained from blood and calculated risk scores based on Vpr amino acid 37, 41 and 55 variants that were previously associated with cognitive performance. RESULTS Global cognitive scores declined significantly over the 1-year study period (p = 0.029). A reduction in global cognitive scores was associated with childhood trauma experience (p = 0.039).
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Affiliation(s)
- Jacqueline S Womersley
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, Francie van Zijl Drive, Tygerberg, 7505, South Africa.
- South African Medical Research Council/Stellenbosch University Genomics of Brain Disorders Research Unit, Francie van Zijl Drive, Tygerberg, 7505, South Africa.
| | - Lara B Clauss
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, Francie van Zijl Drive, Tygerberg, 7505, South Africa
- Joint Master in Neuroscience, Faculty of Life Sciences, University of Strasbourg, Strasbourg, France
| | - Olivette Varathan
- Division of Medical Virology, Faculty of Medicine and Health Sciences, Stellenbosch University, Francie van Zijl Drive, Tygerberg, 7505, South Africa
| | - Susan Engelbrecht
- Division of Medical Virology, Faculty of Medicine and Health Sciences, Stellenbosch University, Francie van Zijl Drive, Tygerberg, 7505, South Africa
- National Health Laboratory Services (NHLS), Tygerberg Coastal, Tygerberg, Western Cape Region, South Africa
| | - Sian M J Hemmings
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, Francie van Zijl Drive, Tygerberg, 7505, South Africa
- South African Medical Research Council/Stellenbosch University Genomics of Brain Disorders Research Unit, Francie van Zijl Drive, Tygerberg, 7505, South Africa
| | - Soraya Seedat
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, Francie van Zijl Drive, Tygerberg, 7505, South Africa
- South African Medical Research Council/Stellenbosch University Genomics of Brain Disorders Research Unit, Francie van Zijl Drive, Tygerberg, 7505, South Africa
| | - Georgina Spies
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, Francie van Zijl Drive, Tygerberg, 7505, South Africa
- South African Medical Research Council/Stellenbosch University Genomics of Brain Disorders Research Unit, Francie van Zijl Drive, Tygerberg, 7505, South Africa
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12
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Vpr and Its Cellular Interaction Partners: R We There Yet? Cells 2019; 8:cells8111310. [PMID: 31652959 PMCID: PMC6912716 DOI: 10.3390/cells8111310] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 10/22/2019] [Accepted: 10/23/2019] [Indexed: 12/17/2022] Open
Abstract
Vpr is a lentiviral accessory protein that is expressed late during the infection cycle and is packaged in significant quantities into virus particles through a specific interaction with the P6 domain of the viral Gag precursor. Characterization of the physiologically relevant function(s) of Vpr has been hampered by the fact that in many cell lines, deletion of Vpr does not significantly affect viral fitness. However, Vpr is critical for virus replication in primary macrophages and for viral pathogenesis in vivo. It is generally accepted that Vpr does not have a specific enzymatic activity but functions as a molecular adapter to modulate viral or cellular processes for the benefit of the virus. Indeed, many Vpr interacting factors have been described by now, and the goal of this review is to summarize our current knowledge of cellular proteins targeted by Vpr.
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Roebuck KA, Saifuddin M. Regulation of HIV-1 transcription. Gene Expr 2018; 8:67-84. [PMID: 10551796 PMCID: PMC6157391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Human immunodeficiency virus type-1 (HIV-1) is a highly pathogenic lentivirus that requires transcription of its provirus genome for completion of the viral life cycle and the production of progeny virions. Since the first genetic analysis of HIV-1 in 1985, much has been learned about the transcriptional regulation of the HIV-1 genome in infected cells. It has been demonstrated that HIV-1 transcription depends on a varied and complex interaction of host cell transcription factors with the viral long terminal repeat (LTR) promoter. The regulatory elements within the LTR interact with constitutive and inducible transcription factors to direct the assembly of a stable transcription complex that stimulates multiple rounds of transcription by RNA polymerase II (RNAPII). However, the majority of these transcripts terminate prematurely in the absence of the virally encoded trans-activator protein Tat, which stimulates HIV-1 transcription elongation by interacting with a stem-loop RNA element (TAR) formed at the extreme 5' end of all viral transcripts. The Tat-TAR interaction recruits a cellular kinase into the initiation-elongation complex that alters the elongation properties of RNAPII during its transit through TAR. This review summarizes our current knowledge and understanding of the regulation of HIV-1 transcription in infected cells and highlights the important contributions human lentivirus gene regulation has made to our general understanding of the transcription process.
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Affiliation(s)
- K A Roebuck
- Department of Immunology/Microbiology, Rush Presbyterian St. Luke's Medical Center, Chicago, IL 60612, USA.
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Mirza FS, Luthra P, Chirch L. Endocrinological aspects of HIV infection. J Endocrinol Invest 2018; 41:881-899. [PMID: 29313284 DOI: 10.1007/s40618-017-0812-x] [Citation(s) in RCA: 17] [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] [Received: 05/15/2017] [Accepted: 12/16/2017] [Indexed: 02/06/2023]
Abstract
PURPOSE Patients with human immunodeficiency virus (HIV) are living longer with effective antiretroviral therapies and are enjoying near normal life span. Therefore, they are encountering endocrine issues faced by the general population along with those specific to HIV infection. The purpose of this article is to review the common endocrine aspects of HIV infection, and the early detection and management strategies for these complications. METHODS Recent literature on HIV and endocrine disease was reviewed. RESULTS HIV can influence endocrine glands at several levels. Endocrine glandular function may be altered by the direct effect of HIV viral proteins, through generation of systemic and local cytokines and the inflammatory response and via glandular involvement with opportunistic infections and HIV-related malignancies. Endocrine disorders seen in people with HIV include metabolic issues related to obesity such as diabetes, hyperlipidemia, lipohypertrophy, lipoatrophy and lipodystrophy and contribute significantly to quality of life, morbidity and mortality. In addition, hypogonadism, osteopenia and osteoporosis are also more prevalent in the patients with HIV. Although disorders of hypothalamic-pituitary-adrenal axis resulting in adrenal insufficiency can be life threatening, these along with thyroid dysfunction are being seen less commonly in the antiretroviral therapy (ART) era. ARTs have greatly improved life expectancy in people living with HIV but can also have adverse endocrine effects. CONCLUSIONS Clinicians need to have a high index of suspicion for endocrine abnormalities in people with HIV as they can be potentially life threatening if untreated. Endocrine evaluation should be pursued as in the general population, with focus on prevention, early detection and treatment to improve quality of life and longevity.
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Affiliation(s)
- F S Mirza
- Division of Endocrinology and Metabolism, Department of Medicine, UConn Health, 263 Farmington Avenue, Farmington, CT, 06030-5456, USA.
- Department of Medicine, UConn Health, Farmington, CT, 06030, USA.
| | - P Luthra
- Division of Endocrinology and Metabolism, Department of Medicine, UConn Health, 263 Farmington Avenue, Farmington, CT, 06030-5456, USA
- Department of Medicine, UConn Health, Farmington, CT, 06030, USA
| | - L Chirch
- Division of Infectious Diseases, UConn Health, Farmington, CT, 06030, USA
- Department of Medicine, UConn Health, Farmington, CT, 06030, USA
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Takashina T, Koyama T, Nohara S, Hasegawa M, Ishiguro A, Iijima K, Lu J, Shimura M, Okamura T, Sakuma T, Yamamoto T, Ishizaka Y. Identification of a cell-penetrating peptide applicable to a protein-based transcription activator-like effector expression system for cell engineering. Biomaterials 2018; 173:11-21. [PMID: 29734017 DOI: 10.1016/j.biomaterials.2018.04.040] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 04/21/2018] [Indexed: 02/08/2023]
Abstract
Cellular reprogramming is a promising technology in regenerative medicine, but most studies have been performed by using expression vectors. For future clinical applications, it is necessary to establish a system in which cell engineering can be manipulated without any risk of damaging the genome. Here, we identified a cell-penetrating peptide composed of 10 amino acids (RIFIHFRIGC) with nuclear trafficking activity and found that it was significantly more potent than a Tat-derived peptide or polyarginine peptide (R11). We named the peptide "nuclear trafficking peptide" (NTP) and applied it to a protein-based artificial transcription factor (NTP-ATF), which was composed of a transcription activator-like effector and transcription domain (VP64). An NTP-ATF designed to the proximal promoter region of the microRNA-302/367 cluster efficiently induced endogenous RNA expression at an extremely low concentration (0.25 nM), and repetitive treatment of mouse embryonic fibroblasts with NTP-ATF generated induced pluripotent stem-like cells, which gave chimeric mice. Together with the observation that recombinant NTP-ATF protein did not induce any apparent cytotoxicity, we propose that NTP-ATF is a promising system for cellular reprogramming applicable to regenerative medicine.
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Affiliation(s)
- Tomoki Takashina
- Department of Intractable Diseases, National Center for Global Health and Medicine, Toyama 1-21-1, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Takayoshi Koyama
- Department of Intractable Diseases, National Center for Global Health and Medicine, Toyama 1-21-1, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Satoshi Nohara
- Nagoya Research Laboratory, Meito Sangyo Co., Ltd., 25-5 Kaechi, Nishibiwajima, Kiyosu, Aichi, 452-0067, Japan
| | - Masakatsu Hasegawa
- Nagoya Research Laboratory, Meito Sangyo Co., Ltd., 25-5 Kaechi, Nishibiwajima, Kiyosu, Aichi, 452-0067, Japan
| | - Akira Ishiguro
- Department of Intractable Diseases, National Center for Global Health and Medicine, Toyama 1-21-1, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Kenta Iijima
- Department of Intractable Diseases, National Center for Global Health and Medicine, Toyama 1-21-1, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Jun Lu
- Department of Intractable Diseases, National Center for Global Health and Medicine, Toyama 1-21-1, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Mari Shimura
- Department of Intractable Diseases, National Center for Global Health and Medicine, Toyama 1-21-1, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Tadashi Okamura
- Section of Animal Models, Department of Infectious Diseases, National Center for Global Health and Medicine, Toyama 1-21-1, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Tetsushi Sakuma
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Takashi Yamamoto
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Yukihito Ishizaka
- Department of Intractable Diseases, National Center for Global Health and Medicine, Toyama 1-21-1, Shinjuku-ku, Tokyo 162-8655, Japan.
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Vitellius G, Trabado S, Bouligand J, Delemer B, Lombès M. Pathophysiology of Glucocorticoid Signaling. ANNALES D'ENDOCRINOLOGIE 2018; 79:98-106. [PMID: 29685454 DOI: 10.1016/j.ando.2018.03.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Glucocorticoids (GC), such as cortisol or dexamethasone, control various physiological functions, notably those involved in development, metabolism, inflammatory processes and stress, and exert most of their effects upon binding to the glucocorticoid receptor (GR, encoded by NR3C1 gene). GC signaling follows several consecutive steps leading to target gene transactivation, including ligand binding, nuclear translocation of ligand-activated GR complexes, DNA binding, coactivator interaction and recruitment of functional transcriptional machinery. Any step may be impaired and may account for altered GC signaling. Partial or generalized glucocorticoid resistance syndrome may result in a reduced level of functional GR, a decreased hormone affinity and binding, a defect in nuclear GR translocation, a decrease or lack of DNA binding and/or post-transcriptional GR modifications. To date, 26 loss-of-function NR3C1 mutations have been reported in the context of hypertension, hirsutism, adrenal hyperplasia or metabolic disorders. These clinical signs are generally associated with biological features including hypercortisolism without negative regulatory feedback loop on the hypothalamic-pituitary-adrenal axis. Patients had often low plasma aldosterone and renin levels despite hypertension. Only one GR gain-of-function mutation has been described associating Cushing's syndrome phenotype with normal urinary-free cortisol. Some GR polymorphisms (ER22/23EK, GR-9β) have been linked to glucocorticoid resistance and a healthier metabolic profile whereas some others seemed to be associated with GC hypersensitivity (N363S, BclI), increasing cardiovascular risk (diabetes type 2, visceral obesity). This review focuses on the earlier findings on the pathophysiology of GR signaling and presents criteria facilitating identification of novel NR3C1 mutations in selected patients.
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Affiliation(s)
- Géraldine Vitellius
- Inserm Umr_S U1185, faculté de médecine Paris-Sud, université Paris-Sud, université Paris-Saclay, 94276 Le Kremlin-Bicêtre, France; Service d'endocrinologie diabète nutrition, CHU de Reims, hôpital Robert-Debré, 51100, France
| | - Séverine Trabado
- Inserm Umr_S U1185, faculté de médecine Paris-Sud, université Paris-Sud, université Paris-Saclay, 94276 Le Kremlin-Bicêtre, France; Service de génétique moléculaire, pharmacogénétique et hormonologie, CHU de Bicêtre, hôpitaux universitaires Paris-Sud, AH-HP, 94275, France
| | - Jérôme Bouligand
- Inserm Umr_S U1185, faculté de médecine Paris-Sud, université Paris-Sud, université Paris-Saclay, 94276 Le Kremlin-Bicêtre, France; Service de génétique moléculaire, pharmacogénétique et hormonologie, CHU de Bicêtre, hôpitaux universitaires Paris-Sud, AH-HP, 94275, France
| | - Brigitte Delemer
- Service d'endocrinologie diabète nutrition, CHU de Reims, hôpital Robert-Debré, 51100, France
| | - Marc Lombès
- Inserm Umr_S U1185, faculté de médecine Paris-Sud, université Paris-Sud, université Paris-Saclay, 94276 Le Kremlin-Bicêtre, France; Service d'endocrinologie et des maladies de la reproduction, hôpitaux universitaires Paris-Sud, CHU Bicêtre, AH-HP, 94275 Le Kremlin Bicêtre, France.
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Suzuki S, Iben JR, Coon SL, Kino T. SIRT1 is a transcriptional enhancer of the glucocorticoid receptor acting independently to its deacetylase activity. Mol Cell Endocrinol 2018; 461:178-187. [PMID: 28923345 PMCID: PMC5756502 DOI: 10.1016/j.mce.2017.09.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 09/10/2017] [Accepted: 09/13/2017] [Indexed: 12/21/2022]
Abstract
Glucocorticoids have strong effects on diverse human activities through the glucocorticoid receptor (GR). Sirtuin 1 (SIRT1) is a NAD+-dependent histone deacetylase and promotes longevity by influencing intermediary metabolism and other regulatory activities including mitochondrial function. In this study, we examined the effects of SIRT1 on GR-mediated transcriptional activity. We found that SIRT1 enhanced GR-induced transcriptional activity on endogenous and exogenous glucocorticoid-responsive genes, whereas knockdown of SIRT1 attenuated it. This effect of SIRT1 was independent to its deacetylase activity, as the SIRT1 mutant defective in this activity (H363Y) enhanced GR transcriptional activity, and the compounds inhibiting or activating the SIRT1 deacetylase activity did not influence it. RNA-seq analysis revealed that SIRT1 knockdown influenced ∼30% of the glucocorticoid-responsive transcriptome for most of which it acted as an enhancer for positive/negative effects of this hormone. SIRT1 physically interacted with GR, and was attracted to GR-bound glucocorticoid response elements in a glucocorticoid-dependent fashion. SIRT1 cooperatively activated GR transcriptional activity with the PPARγ coactivator-1α also in its deacetylase activity-independent fashion. Thus, SIRT1 is a novel transcriptional enhancer of GR-induced transcriptional activity possibly by functioning as a scaffold for the transcriptional complex formed on GR.
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Affiliation(s)
- Shigeru Suzuki
- Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA; Department of Pediatrics, Asahikawa Medical University, Asahikawa 078-8510, Japan.
| | - James R Iben
- Molecular Genomics Core, Eunice Kennedy Shriver National Institutes of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Steven L Coon
- Molecular Genomics Core, Eunice Kennedy Shriver National Institutes of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Tomoshige Kino
- Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA; Division of Translational Medicine, Sidra Medical and Research Center, Doha 26999, Qatar.
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Abstract
HIV infection and antiretroviral therapy (ART) treatment exert diverse effects on adipocytes and stromal-vascular fraction cells, leading to changes in adipose tissue quantity, distribution, and energy storage. A HIV-associated lipodystrophic condition was recognized early in the epidemic, characterized by clinically apparent changes in subcutaneous, visceral, and dorsocervical adipose depots. Underlying these changes is altered adipose tissue morphology and expression of genes central to adipocyte maturation, regulation, metabolism, and cytokine signaling. HIV viral proteins persist in circulation and locally within adipose tissue despite suppression of plasma viremia on ART, and exposure to these proteins impairs preadipocyte maturation and reduces adipocyte expression of peroxisome proliferator-activated receptor gamma (PPAR-γ) and other genes involved in cell regulation. Several early nucleoside reverse transcriptase inhibitor and protease inhibitor antiretroviral drugs demonstrated substantial adipocyte toxicity, including reduced mitochondrial DNA content and respiratory chain enzymes, reduced PPAR-γ and other regulatory gene expression, and increased proinflammatory cytokine production. Newer-generation agents, such as integrase inhibitors, appear to have fewer adverse effects. HIV infection also alters the balance of CD4+ and CD8+ T cells in adipose tissue, with effects on macrophage activation and local inflammation, while the presence of latently infected CD4+ T cells in adipose tissue may constitute a protected viral reservoir. This review provides a synthesis of the literature on how HIV virus, ART treatment, and host characteristics interact to affect adipose tissue distribution, immunology, and contribution to metabolic health, and adipocyte maturation, cellular regulation, and energy storage. © 2017 American Physiological Society. Compr Physiol 7:1339-1357, 2017.
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Affiliation(s)
- John R Koethe
- Division of Infectious Diseases, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
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Maggi P, Di Biagio A, Rusconi S, Cicalini S, D'Abbraccio M, d'Ettorre G, Martinelli C, Nunnari G, Sighinolfi L, Spagnuolo V, Squillace N. Cardiovascular risk and dyslipidemia among persons living with HIV: a review. BMC Infect Dis 2017; 17:551. [PMID: 28793863 PMCID: PMC5550957 DOI: 10.1186/s12879-017-2626-z] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 07/20/2017] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Aim of this review is to focus the attention on people living with HIV infection at risk of developing a cardiovascular event. What is or what would be the most suitable antiretroviral therapy? Which statin or fibrate to reduce the risk? How to influence behavior and lifestyles? DISCUSSION Prevention of cardiovascular disease (CVD) risk remains the first and essential step in a medical intervention on these patients. The lifestyle modification, including smoking cessation, increased physical activity, weight reduction, and the education on healthy dietary practices are the main instruments. Statins are the cornerstone for the treatment of hypercholesterolemia. They have been shown to slow the progression or promote regression of coronary plaque, and could also exert an anti-inflammatory and immunomodulatory effect. However the current guidelines for the use of these drugs in general population are dissimilar, with important differences between American and European ones. The debate between American and European guidelines is still open and, also considering the independent risk factor represented by HIV, specific guidelines are warranted. Ezetimibe reduces the intestinal absorption of cholesterol. It is effective alone or in combination with rosuvastatin. It does not modify plasmatic concentrations of antiretrovirals. A number of experimental new classes of drugs for the treatment of hypercholesterolemia are being studied. Fibrates represent the first choice for treatment of hypertriglyceridemia, however, the renal toxicity of fibrates and statins should be considered. Omega 3 fatty acids have a good safety profile, but their efficacy is limited. Another concern is the high dose needed. Other drugs are acipimox and tesamorelin. Current antiretroviral therapies are less toxic and more effective than regimens used in the early years. Lipodistrophy and dyslipidemia are the main causes of long-term toxicities. Not all antiretrovirals have similar toxicities. Protease Inhibitors may cause dyslipidemia and lipodystrophy, while integrase inhibitors have a minimal impact on lipids profile, and no evidence of lipodystrophy. There is still much to be written with the introduction of new drugs in clinical practice. CONCLUSIONS Cardiovascular risk among HIV infected patients, interventions on behavior and lifestyles, use of drugs to reduce the risk, and switch in antiretroviral therapy, remain nowadays major issues in the management of HIV-infected patients.
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Affiliation(s)
- Paolo Maggi
- Clinica Malattie Infettive Policlinico, Bari, Italy.
| | - Antonio Di Biagio
- Clinica Malattie Infettive, Policlinico Ospedale S. Martino, Genoa, Italy
| | - Stefano Rusconi
- Divisione Clinicizzata di Malattie Infettive, DIBIC L. Sacco, Università degli Studi di Milano, Milan, Italy
| | | | - Maurizio D'Abbraccio
- UOC. di Immunodeficienze e Malattie Infettive di Genere, P.O. "D. Cotugno", AORN Dei Colli, Naples, Italy
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Genome-wide Regulatory Roles of the C2H2-type Zinc Finger Protein ZNF764 on the Glucocorticoid Receptor. Sci Rep 2017; 7:41598. [PMID: 28139699 PMCID: PMC5282477 DOI: 10.1038/srep41598] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 12/23/2016] [Indexed: 01/13/2023] Open
Abstract
The C2H2-type zinc finger protein ZNF764 acts as an enhancer for several steroid hormone receptors, and haploinsufficiency of this gene may be responsible for tissue resistance to multiple steroid hormones including glucocorticoids observed in a patient with 16p11.2 microdeletion. We examined genome-wide regulatory actions of ZNF764 on the glucocorticoid receptor (GR) in HeLa cells as a model system. ZNF764- and GR-binding sites demonstrated similar distribution in various genomic features. They positioned predominantly around 50–500 kbs from the transcription start sites of their nearby genes, and were closely localized with each other, overlapping in ~37% of them. ZNF764 demonstrated differential on/off effects on GR-binding and subsequent mRNA expression: some genes were highly dependent on the presence/absence of ZNF764, but others were not. Pathway analysis revealed that these 3 gene groups were involved in distinct cellular activities. ZNF764 physically interacted with GR at ligand-binding domain through its KRAB domain, and both its physical interaction to GR and zinc finger domain appear to be required for ZNF764 to regulate GR transcriptional activity. Thus, ZNF764 is a cofactor directing GR transcriptional activity toward specific biologic pathways by changing GR binding and transcriptional activity on the glucocorticoid-responsive genes.
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González ME. The HIV-1 Vpr Protein: A Multifaceted Target for Therapeutic Intervention. Int J Mol Sci 2017; 18:ijms18010126. [PMID: 28075409 PMCID: PMC5297760 DOI: 10.3390/ijms18010126] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 12/22/2016] [Accepted: 01/03/2017] [Indexed: 12/16/2022] Open
Abstract
The human immunodeficiency virus type 1 (HIV-1) Vpr protein is an attractive target for antiretroviral drug development. The conservation both of the structure along virus evolution and the amino acid sequence in viral isolates from patients underlines the importance of Vpr for the establishment and progression of HIV-1 disease. While its contribution to virus replication in dividing and non-dividing cells and to the pathogenesis of HIV-1 in many different cell types, both extracellular and intracellular forms, have been extensively studied, its precise mechanism of action nevertheless remains enigmatic. The present review discusses how the apparently multifaceted interplay between Vpr and host cells may be due to the impairment of basic metabolic pathways. Vpr protein modifies host cell energy metabolism, oxidative status, and proteasome function, all of which are likely conditioned by the concentration and multimerization of the protein. The characterization of Vpr domains along with new laboratory tools for the assessment of their function has become increasingly relevant in recent years. With these advances, it is conceivable that drug discovery efforts involving Vpr-targeted antiretrovirals will experience substantial growth in the coming years.
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Affiliation(s)
- María Eugenia González
- Unidad de Expresión Viral, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Carretera de Majadahonda-Pozuelo Km 2, Majadahonda, 28220 Madrid, Spain.
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Habib T, Sadoun A, Nader N, Suzuki S, Liu W, Jithesh PV, Kino T. AKT1 has dual actions on the glucocorticoid receptor by cooperating with 14-3-3. Mol Cell Endocrinol 2017; 439:431-443. [PMID: 27717743 DOI: 10.1016/j.mce.2016.10.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 10/02/2016] [Accepted: 10/03/2016] [Indexed: 01/08/2023]
Abstract
Glucocorticoids are important therapeutic compounds for acute lymphoblastic leukemia (ALL). AKT1 or the protein kinase B is frequently activated in ALL, and contributes to the development of glucocorticoid resistance. We examined impact of AKT1 on glucocorticoid receptor (GR)-induced transcriptional activity in cooperation with phospho-serine/threonine-binding protein 14-3-3. AKT1 has two distinct actions on GR transcriptional activity, one through segregation of GR in the cytoplasm by phosphorylating GR at Ser-134 and subsequent association of 14-3-3, and the other through direct modulation of GR transcriptional activity in the nucleus. For the latter, AKT1 and 14-3-3 are attracted to DNA-bound GR, accompanied by AKT1-dependent p300 phosphorylation, H3S10 phosphorylation and H3K14 acetylation at the DNA site. These two actions of AKT1 regulate distinct sets of glucocorticoid-responsive genes. Our results suggest that specific inhibition of the AKT1/14-3-3 activity on the cytoplasmic retention of GR may be a promising target for treating glucocorticoid resistance observed in ALL.
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Affiliation(s)
- Tanwir Habib
- Division of System Biology, Sidra Medical and Research Center, Out Patient Clinic, PO Box 26999, Al Luqta Street, Education City North Campus, Doha, Qatar.
| | - Ameera Sadoun
- Division of Translational Medicine, Sidra Medical and Research Center, Out Patient Clinic, PO Box 26999, Al Luqta Street, Education City North Campus, Doha, Qatar.
| | - Nancy Nader
- Physiology and Biophysics, Weill Cornell University in Qatar, PO Box 24144, Al Luqta Street, Education City South Campus, Doha, Qatar.
| | - Shigeru Suzuki
- Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bldg. 10, CRC, Rm 1-3140, 10 Center Drive MSC 1109, Bethesda, MD 20892, USA; Department of Pediatrics, Asahikawa Medical University, Asahikawa, 078-8510, Japan.
| | - Wei Liu
- Division of Genomic Core, Sidra Medical and Research Center, Out Patient Clinic, PO Box 26999, Al Luqta Street, Education City North Campus, Doha, Qatar.
| | - Puthen V Jithesh
- Division of System Biology, Sidra Medical and Research Center, Out Patient Clinic, PO Box 26999, Al Luqta Street, Education City North Campus, Doha, Qatar.
| | - Tomoshige Kino
- Division of Translational Medicine, Sidra Medical and Research Center, Out Patient Clinic, PO Box 26999, Al Luqta Street, Education City North Campus, Doha, Qatar; Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bldg. 10, CRC, Rm 1-3140, 10 Center Drive MSC 1109, Bethesda, MD 20892, USA.
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23
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Contoreggi C, Chrousos GP, Mascio MD. Chronic distress and the vulnerable host: a new target for HIV treatment and prevention? NEUROBEHAVIORAL HIV MEDICINE 2016; 7:53-75. [PMID: 34295195 PMCID: PMC8293862 DOI: 10.2147/nbhiv.s86309] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Pathologic stress (distress) disturbs immune, cardiovascular, metabolic, and behavioral homeostasis. Individuals living with HIV and those at risk are vulnerable to stress disorders. Corticotropin-releasing hormone (CRH) is critical in neuroendocrine immune regulation. CRH, a neuropeptide, is distributed in the central and peripheral nervous systems and acts principally on CRH receptor type 1 (CRHR1). CRH in the brain modulates neuropsychiatric disorders. CRH and stress modulation of immunity is two-pronged; there is a direct action on hypothalamic-pituitary-adrenal secretion of glucocorticoids and through immune organ sympathetic innervation. CRH is a central and systemic proinflammatory cytokine. Glucocorticoids and their receptors have gene regulatory actions on viral replication and cause central and systemic immune suppression. CRH and stress activation contributes to central nervous system (CNS) viral entry important in HIV-associated neurocognitive disorders and HIV-associated dementia. CNS CRH overproduction short-circuits reward, executive, and emotional control, leading to addiction, cognitive impairment, and psychiatric comorbidity. CRHR1 is an important therapeutic target for medication development. CRHR1 antagonist clinical trials have focused on psychiatric disorders with little attention paid to neuroendocrine immune disorders. Studies of those with HIV and those at risk show that concurrent stress-related disorders contribute to higher morbidity and mortality; stress-related conditions, addiction, immune dysfunction, and comorbid psychiatric illness all increase HIV transmission. Neuropsychiatric disease, chronic inflammation, and substance abuse are endemic, and chronic distress is a pathologic factor. It is being understood that stress and CRH are fundamental to neuroendocrine immunity; therapeutic interventions with existing and novel agents hold promise for restoring homeostasis, reducing morbidity and mortality for those with HIV and possibly reducing future disease transmission.
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Affiliation(s)
- Carlo Contoreggi
- Intramural Research Program (IRP), National Institute on Drug Abuse (NIDA), National Institutes of Health (NIH), Baltimore, MD, USA
| | - George P Chrousos
- Department of Pediatrics, Aghia Sophia Children’s Hospital, National and Kapodistrian University of Athens Medical School, Athens, Greece
| | - Michele Di Mascio
- AIDS Imaging Research Section, Division of Clinical Research, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD, USA
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Hapgood JP, Avenant C, Moliki JM. Glucocorticoid-independent modulation of GR activity: Implications for immunotherapy. Pharmacol Ther 2016; 165:93-113. [PMID: 27288728 DOI: 10.1016/j.pharmthera.2016.06.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 05/16/2016] [Indexed: 12/19/2022]
Abstract
Pharmacological doses of glucocorticoids (GCs), acting via the glucocorticoid receptor (GR) to repress inflammation and immune function, remain the most effective therapy in the treatment of inflammatory and immune diseases. Since many patients on GC therapy exhibit GC resistance and severe side-effects, much research is focused on developing more selective GCs and combination therapies, with greater anti-inflammatory potency. GCs mediate their classical genomic transcriptional effects by binding to the cytoplasmic GR, followed by nuclear translocation and modulation of transcription of target genes by direct DNA binding of the GR or its tethering to other transcription factors. Recent evidence suggests, however, that the responses mediated by the GR are much more complex and involve multiple parallel mechanisms integrating simultaneous signals from other receptors, both in the absence and presence of GCs, to shift the sensitivity of a target cell to GCs. The level of cellular stress, immune activation status, or the cell cycle phase may be crucial for determining GC sensitivity and GC responsiveness as well as subcellular localization of the GR and GR levels. Central to the development of new drugs that target GR signaling alone or as add-on therapies, is an in-depth understanding of the molecular mechanisms of GC-independent GR desensitization, priming and activation of the unliganded GR, as well as synergy and cross-talk with other signaling pathways. This review will discuss the information currently available on these topics and their relevance to immunotherapy, as well as identify unanswered questions and future areas of research.
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Affiliation(s)
- Janet P Hapgood
- Department of Molecular and Cell Biology, University of Cape Town, Private Bag X3, Rondebosch, 7700, South Africa.
| | - Chanel Avenant
- Department of Molecular and Cell Biology, University of Cape Town, Private Bag X3, Rondebosch, 7700, South Africa
| | - Johnson M Moliki
- Department of Molecular and Cell Biology, University of Cape Town, Private Bag X3, Rondebosch, 7700, South Africa
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The Interactome of the Glucocorticoid Receptor and Its Influence on the Actions of Glucocorticoids in Combatting Inflammatory and Infectious Diseases. Microbiol Mol Biol Rev 2016; 80:495-522. [PMID: 27169854 DOI: 10.1128/mmbr.00064-15] [Citation(s) in RCA: 123] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Glucocorticoids (GCs) have been widely used for decades as a first-line treatment for inflammatory and autoimmune diseases. However, their use is often hampered by the onset of adverse effects or resistance. GCs mediate their effects via binding to glucocorticoid receptor (GR), a transcription factor belonging to the family of nuclear receptors. An important aspect of GR's actions, including its anti-inflammatory capacity, involves its interactions with various proteins, such as transcription factors, cofactors, and modifying enzymes, which codetermine receptor functionality. In this review, we provide a state-of-the-art overview of the protein-protein interactions (PPIs) of GR that positively or negatively affect its anti-inflammatory properties, along with mechanistic insights, if known. Emphasis is placed on the interactions that affect its anti-inflammatory effects in the presence of inflammatory and microbial diseases.
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26
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Defining the roles for Vpr in HIV-1-associated neuropathogenesis. J Neurovirol 2016; 22:403-15. [PMID: 27056720 DOI: 10.1007/s13365-016-0436-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 03/14/2016] [Accepted: 03/15/2016] [Indexed: 12/22/2022]
Abstract
It is increasingly evident that the human immunodeficiency virus type 1 (HIV-1) viral protein R (Vpr) has a unique role in neuropathogenesis. Its ability to induce G2/M arrest coupled with its capacity to increase viral gene transcription gives it a unique role in sustaining viral replication and aiding in the establishment and maintenance of a systemic infection. The requirement of Vpr for HIV-1 infection and replication in cells of monocytic origin (a key lineage of cells involved in HIV-1 neuroinvasion) suggests an important role in establishing and sustaining infection in the central nervous system (CNS). Contributions of Vpr to neuropathogenesis can be expanded further through (i) naturally occurring HIV-1 sequence variation that results in functionally divergent Vpr variants; (ii) the dual activities of Vpr as a intracellular protein delivered and expressed during HIV-1 infection and as an extracellular protein that can act on neighboring, uninfected cells; (iii) cell type-dependent consequences of Vpr expression and exposure, including cell cycle arrest, metabolic dysregulation, and cytotoxicity; and (iv) the effects of Vpr on exosome-based intercellular communication in the CNS. Revealing that the effects of this pleiotropic viral protein is an essential part of a greater understanding of HIV-1-associated pathogenesis and potential approaches to treating and preventing disease caused by HIV-1 infection.
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Sobhy H. A Review of Functional Motifs Utilized by Viruses. Proteomes 2016; 4:proteomes4010003. [PMID: 28248213 PMCID: PMC5217368 DOI: 10.3390/proteomes4010003] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 01/07/2016] [Accepted: 01/13/2016] [Indexed: 01/05/2023] Open
Abstract
Short linear motifs (SLiM) are short peptides that facilitate protein function and protein-protein interactions. Viruses utilize these motifs to enter into the host, interact with cellular proteins, or egress from host cells. Studying functional motifs may help to predict protein characteristics, interactions, or the putative cellular role of a protein. In virology, it may reveal aspects of the virus tropism and help find antiviral therapeutics. This review highlights the recent understanding of functional motifs utilized by viruses. Special attention was paid to the function of proteins harboring these motifs, and viruses encoding these proteins. The review highlights motifs involved in (i) immune response and post-translational modifications (e.g., ubiquitylation, SUMOylation or ISGylation); (ii) virus-host cell interactions, including virus attachment, entry, fusion, egress and nuclear trafficking; (iii) virulence and antiviral activities; (iv) virion structure; and (v) low-complexity regions (LCRs) or motifs enriched with residues (Xaa-rich motifs).
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Affiliation(s)
- Haitham Sobhy
- Department of Molecular Biology, Umeå University, 901 87 Umeå, Sweden.
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Hill MJ, Suzuki S, Segars JH, Kino T. CRTC2 Is a Coactivator of GR and Couples GR and CREB in the Regulation of Hepatic Gluconeogenesis. Mol Endocrinol 2016; 30:104-17. [PMID: 26652733 PMCID: PMC4695631 DOI: 10.1210/me.2015-1237] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 11/25/2015] [Indexed: 12/22/2022] Open
Abstract
Glucocorticoid hormones play essential roles in the regulation of gluconeogenesis in the liver, an adaptive response that is required for the maintenance of circulating glucose levels during fasting. Glucocorticoids do this by cooperating with glucagon, which is secreted from pancreatic islets to activate the cAMP-signaling pathway in hepatocytes. The cAMP-response element-binding protein (CREB)-regulated transcription coactivator 2 (CRTC2) is a coactivator known to be specific to CREB and plays a central role in the glucagon-mediated activation of gluconeogenesis in the early phase of fasting. We show here that CRTC2 also functions as a coactivator for the glucocorticoid receptor (GR). CRTC2 strongly enhances GR-induced transcriptional activity of glucocorticoid-responsive genes. CRTC2 physically interacts with the ligand-binding domain of the GR through a region spanning amino acids 561-693. Further, CRTC2 is required for the glucocorticoid-associated cooperative mRNA expression of the glucose-6-phosphatase, a rate-limiting enzyme for hepatic gluconeogenesis, by facilitating the attraction of GR and itself to its promoter region already occupied by CREB. CRTC2 is required for the maintenance of blood glucose levels during fasting in mice by enhancing the GR transcriptional activity on both the G6p and phosphoenolpyruvate carboxykinase (Pepck) genes. Finally, CRTC2 modulates the transcriptional activity of the progesterone receptor, indicating that it may influence the transcriptional activity of other steroid/nuclear receptors. Taken together, these results reveal that CRTC2 plays an essential role in the regulation of hepatic gluconeogenesis through coordinated regulation of the glucocorticoid/GR- and glucagon/CREB-signaling pathways on the key genes G6P and PEPCK.
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Affiliation(s)
- Micah J Hill
- Program in Reproductive and Adult Endocrinology (M.J.H., S.S., J.H.S., T.K.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Division of Reproductive Endocrinology and Infertility (M.J.H.), Walter Reed National Military Medical Center, Bethesda, Maryland 20889; Department of Pediatrics (S.S.), Asahikawa Medical University, Asahikawa 078-8510, Japan; Division of Reproductive Sciences and Women's Health Research (J.H.S.), Department of Gynecology and Obstetrics, Johns Hopkins School of Medicine, Baltimore, Maryland 21205; and Department of Experimental Therapeutics (T.K.), Division of Experimental Biology, Sidra Medical and Research Center, Doha 26999, Qatar
| | - Shigeru Suzuki
- Program in Reproductive and Adult Endocrinology (M.J.H., S.S., J.H.S., T.K.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Division of Reproductive Endocrinology and Infertility (M.J.H.), Walter Reed National Military Medical Center, Bethesda, Maryland 20889; Department of Pediatrics (S.S.), Asahikawa Medical University, Asahikawa 078-8510, Japan; Division of Reproductive Sciences and Women's Health Research (J.H.S.), Department of Gynecology and Obstetrics, Johns Hopkins School of Medicine, Baltimore, Maryland 21205; and Department of Experimental Therapeutics (T.K.), Division of Experimental Biology, Sidra Medical and Research Center, Doha 26999, Qatar
| | - James H Segars
- Program in Reproductive and Adult Endocrinology (M.J.H., S.S., J.H.S., T.K.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Division of Reproductive Endocrinology and Infertility (M.J.H.), Walter Reed National Military Medical Center, Bethesda, Maryland 20889; Department of Pediatrics (S.S.), Asahikawa Medical University, Asahikawa 078-8510, Japan; Division of Reproductive Sciences and Women's Health Research (J.H.S.), Department of Gynecology and Obstetrics, Johns Hopkins School of Medicine, Baltimore, Maryland 21205; and Department of Experimental Therapeutics (T.K.), Division of Experimental Biology, Sidra Medical and Research Center, Doha 26999, Qatar
| | - Tomoshige Kino
- Program in Reproductive and Adult Endocrinology (M.J.H., S.S., J.H.S., T.K.), Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892; Division of Reproductive Endocrinology and Infertility (M.J.H.), Walter Reed National Military Medical Center, Bethesda, Maryland 20889; Department of Pediatrics (S.S.), Asahikawa Medical University, Asahikawa 078-8510, Japan; Division of Reproductive Sciences and Women's Health Research (J.H.S.), Department of Gynecology and Obstetrics, Johns Hopkins School of Medicine, Baltimore, Maryland 21205; and Department of Experimental Therapeutics (T.K.), Division of Experimental Biology, Sidra Medical and Research Center, Doha 26999, Qatar
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Visnegarwala F, Shlay JC, Barry V, Gibert CL, Xiang Y, Wang J, Kotler D, Raghavan S, El-Sadr WM. Effects of HIV Infection on Body Composition Changes Among Men of Different Racial/Ethnic Origins. HIV CLINICAL TRIALS 2015; 8:145-54. [PMID: 17621461 DOI: 10.1310/hct0803-145] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To compare racial/ethnic differences and effects of HIV on body composition among antiretroviral (ART)-naïve HIV seropositive (HIV+) men to a representative sample of HIV seronegative (HIV-) men. We hypothesized that the effect of HIV infection will be uniform across all racial/ethnic groups. METHOD A cross-sectional analysis was performed comparing HIV- (NHANES 1999-2002) and ART-naïve HIV+ men (CPCRA 061). Regional subcutaneous fat area was estimated by skinfold caliper. Total body fat (TBF), fat-free mass (FFM), and body fat index (BFI) were derived by Durnin-Womersley formula (TBF-DW, FFM-DW, BFI [TBF-DW/height(2)]). Bioelectric impedance analyses (BIA) was used to assess TBF-BIA, FFM-BIA, and body cell mass (BCM). Multivariate regression modeling adjusted for age, smoking, and hepatitis C for each measurement was performed. RESULTS HIV+ men (n = 321) were older and more likely to be smokers than HIV- men (n = 1,996). The HIV- men were heavier in weight (+17.8 kg, p < .001) and had higher BMI (+4.3 kg/m(2), p < .001), BCM (+2.4 kg, p = .02), FFM (+5.9 kg, p < .001), TBF-DW (+5.95 kg, p < .001), BFI (+1.6 kg/m(2), p < .001), and regional fat mass than the HIV+ men. In the multivariate model, there were significant percentage differences between HIV- and HIV+ African American men for all body composition measurements (weight +15.3%; BMI +14.5%; BCM +5.2%; TBF-DW +15%; BFI 13.9%; FFM-DW 7.9%) and all circumference and skinfold measurements; all ps < .05. For Caucasian men, the following differences were significant between HIV- and HIV+: weight +14.4%; BMI +14.0%; BCM +6.0%; TBF-DW +17.7%; BFI 17.1%; FFM-DW 8.7%; and all circumference and skinfold measurements. Similarly, among Latino men the following differences were significant: weight +10.1%; BMI +12.3%; FFM-DW +7.7%; and arm, waist, and thigh circumferences and mid-arm skinfold fat area. The interaction terms for race/ethnicity were not significant across the three racial groups for weight, BMI, BCM, TBF-BIA, and BFI. CONCLUSION Compared to HIV uninfected men, among HIV-infected ART-naïve men there was a significant effect of HIV infection itself on body composition among all racial/ethnic groups.
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Agarwal N, Balasubramanyam A. Viral mechanisms of adipose dysfunction: lessons from HIV-1 Vpr. Adipocyte 2015; 4:55-9. [PMID: 26167403 DOI: 10.4161/adip.29852] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Revised: 07/07/2014] [Accepted: 07/07/2014] [Indexed: 01/02/2023] Open
Abstract
HIV-associated lipodystrophy is a heterogeneous, evolving condition associated with fundamental defects in adipose tissue differentiation, turnover and function. Although many antiretroviral drugs can affect adipose tissues adversely, clinical evidence suggests that factors associated with the virus per se could play a role. We have focused on the possibility that an HIV accessory protein, viral protein R (Vpr) could dysregulate metabolically critical transcription factors to cause the adipose dysfunction. In a recent study published in Science Translational Medicine, we utilized 2 animal models to show that Vpr, produced in tissues that sequester HIV after antiretroviral therapy, can act in a paracrine or endocrine fashion to disrupt adipocyte differentiation and function by inhibiting PPARγ target gene expression and activating glucocorticoid target gene expression. The phenotypic consequences included many features typical of the human syndrome, including accelerated lipolysis, increased macrophage infiltration in adipose tissue, diminished size of white adipose depots and hepatic steatosis. In this commentary, we summarize the background, results, and implications of these studies, and raise important questions for future investigation. More broadly, these studies suggest that chronic viral infections may be a causative factor in the pathogenesis of some forms of lipid metabolic disease, insulin resistance, and diabetes.
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Mahajan S, Saini A, Kalra R, Gupta P. Frienemies of infection: A chronic case of host nuclear receptors acting as cohorts or combatants of infection. Crit Rev Microbiol 2014; 42:526-34. [PMID: 25358058 DOI: 10.3109/1040841x.2014.970122] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Macrophages and dendritic cells provide critical effector functions to efficiently resist and promptly eliminate infection. Pattern recognition receptors signaling operative in these cell types is imperative for their innate properties. However, it is now emerging that besides these conventional signaling pathways, nuclear receptors coupled gene regulation and transrepression pathways assemble immune regulatory networks. A couple of these networks associated with members of nuclear receptor superfamily decide heterogeneity in macrophages and dendritic cells population and thereby play decisive role in determining protective immunity against bacteria, viruses, fungi, protozoa and helminths. Pathogens also direct shift in the expression of nuclear receptors and their target genes and this is proclaimed to be a sui generis mechanism whereby microbes disconnect the genomic component from the peripheral immune response. Many endogenous and synthetic nuclear receptor ligands have been tested in various in vitro and in vivo infection models to study their effect on pathogen burden. Here, we discuss current advances in our understanding of the composite interactions between nuclear receptor and pathogens and their implications on the causatum infectious diseases.
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Affiliation(s)
- Sahil Mahajan
- a Department of Molecular Biology , CSIR Institute of Microbial Technology , Chandigarh , India
| | - Ankita Saini
- a Department of Molecular Biology , CSIR Institute of Microbial Technology , Chandigarh , India
| | - Rashi Kalra
- a Department of Molecular Biology , CSIR Institute of Microbial Technology , Chandigarh , India
| | - Pawan Gupta
- a Department of Molecular Biology , CSIR Institute of Microbial Technology , Chandigarh , India
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Vandevyver S, Dejager L, Libert C. Comprehensive overview of the structure and regulation of the glucocorticoid receptor. Endocr Rev 2014; 35:671-93. [PMID: 24937701 DOI: 10.1210/er.2014-1010] [Citation(s) in RCA: 161] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Glucocorticoids are among the most prescribed drugs worldwide for the treatment of numerous immune and inflammatory disorders. They exert their actions by binding to the glucocorticoid receptor (GR), a member of the nuclear receptor superfamily. There are several GR isoforms resulting from alternative RNA splicing and translation initiation of the GR transcript. Additionally, these isoforms are all subject to several transcriptional, post-transcriptional, and post-translational modifications, all of which affect the protein's stability and/or function. In this review, we summarize recent knowledge on the distinct GR isoforms and the processes that generate them. We also review the importance of all known transcriptional, post-transcriptional, and post-translational modifications, including the regulation of GR by microRNAs. Moreover, we discuss the crucial role of the putative GR-bound DNA sequence as an allosteric ligand influencing GR structure and activity. Finally, we describe how the differential composition and distinct regulation at multiple levels of different GR species could account for the wide and diverse effects of glucocorticoids.
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Affiliation(s)
- Sofie Vandevyver
- Inflammation Research Center (S.V., L.D., C.L.), Flanders Institute for Biotechnology, B9052 Ghent, Belgium; and Department of Biomedical Molecular Biology (S.V., L.D., C.L.), Ghent University, B9052 Ghent, Belgium
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Agarwal N, Iyer D, Patel SG, Sekhar RV, Phillips TM, Schubert U, Oplt T, Buras ED, Samson SL, Couturier J, Lewis DE, Rodriguez-Barradas MC, Jahoor F, Kino T, Kopp JB, Balasubramanyam A. HIV-1 Vpr induces adipose dysfunction in vivo through reciprocal effects on PPAR/GR co-regulation. Sci Transl Med 2014; 5:213ra164. [PMID: 24285483 DOI: 10.1126/scitranslmed.3007148] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Viral infections, such as HIV, have been linked to obesity, but mechanistic evidence that they cause adipose dysfunction in vivo is lacking. We investigated a pathogenic role for the HIV-1 accessory protein viral protein R (Vpr), which can coactivate the glucocorticoid receptor (GR) and co-repress peroxisome proliferator-activated receptor γ (PPARγ) in vitro, in HIV-associated adipose dysfunction. Vpr circulated in the blood of most HIV-infected patients tested, including those on antiretroviral therapy (ART) with undetectable viral load. Vpr-mediated mechanisms were dissected in vivo using mouse models expressing the Vpr transgene in adipose tissues and liver (Vpr-Tg) or infused with synthetic Vpr. Both models demonstrated accelerated whole-body lipolysis, hyperglycemia and hypertriglyceridemia, and tissue-specific findings. Fat depots in these mice had diminished mass, macrophage infiltration, and blunted PPARγ target gene expression but increased GR target gene expression. In liver, we observed blunted PPARα target gene expression, steatosis with decreased adenosine monophosphate-activated protein kinase activity, and insulin resistance. Similar to human HIV-infected patients, Vpr circulated in the serum of Vpr-Tg mice. Vpr blocked differentiation in preadipocytes through cell cycle arrest, whereas in mature adipocytes, it increased lipolysis with reciprocally altered association of PPARγ and GR with their target promoters. These results delineate a distinct pathogenic sequence: Vpr, released from HIV-1 in tissue reservoirs after ART, can disrupt PPAR/GR co-regulation and cell cycle control to produce adipose dysfunction and hepatosteatosis. Confirmation of these mechanisms in HIV patients could lead to targeted treatment of the metabolic complications with Vpr inhibitors, GR antagonists, or PPARγ/PPARα agonists.
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Affiliation(s)
- Neeti Agarwal
- Translational Metabolism Unit, Diabetes Research Center, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, TX 77030, USA
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Association of glucocorticoid receptor haplotypes with body composition and metabolic parameters in HIV-infected patients from the FRAM study. Pharmacogenet Genomics 2014; 24:156-61. [DOI: 10.1097/fpc.0000000000000029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Webster Marketon JI, Corry J, Teng MN. The respiratory syncytial virus (RSV) nonstructural proteins mediate RSV suppression of glucocorticoid receptor transactivation. Virology 2014; 449:62-9. [PMID: 24418538 PMCID: PMC3904736 DOI: 10.1016/j.virol.2013.11.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Revised: 07/12/2013] [Accepted: 11/06/2013] [Indexed: 12/22/2022]
Abstract
Respiratory syncytial virus (RSV)-induced bronchiolitis in infants is not responsive to glucocorticoids. We have shown that RSV infection impairs glucocorticoid receptor (GR) function. In this study, we have investigated the mechanism by which RSV impairs GR function. We have shown that RSV repression of GR-induced transactivation is not mediated through a soluble autocrine factor. Knock-down of mitochondrial antiviral signaling protein (MAVS), but not retinoic acid-inducible gene 1 (RIG-I) or myeloid differentiation primary response gene 88 (MyD88), impairs GR-mediated gene activation even in mock-infected cells. Over-expression of the RSV nonstructural protein NS1, but not NS2, impairs glucocorticoid-induced transactivation and viruses deleted in NS1 and/or NS2 are unable to repress glucocorticoid-induction of the known GR regulated gene glucocorticoid-inducible leucine zipper (GILZ). These data suggest that the RSV nonstructural proteins mediate RSV repression of GR-induced transactivation and that inhibition of the nonstructural proteins may be a viable target for therapy against RSV-related disease.
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Affiliation(s)
- Jeanette I Webster Marketon
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Internal Medicine, Wexner Medical Center at The Ohio State University, Columbus, OH 43210, United States; Institute for Behavioral Medicine Research, Wexner Medical Center at The Ohio State University, Columbus, OH 43210, United States.
| | - Jacqueline Corry
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Internal Medicine, Wexner Medical Center at The Ohio State University, Columbus, OH 43210, United States.
| | - Michael N Teng
- Joy McCann Culverhouse Airway Disease Research Center, Division of Allergy and Immunology, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, United States
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Dahiya S, Irish BP, Nonnemacher MR, Wigdahl B. Genetic variation and HIV-associated neurologic disease. Adv Virus Res 2013; 87:183-240. [PMID: 23809924 DOI: 10.1016/b978-0-12-407698-3.00006-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
HIV-associated neurologic disease continues to be a significant complication in the era of highly active antiretroviral therapy. A substantial subset of the HIV-infected population shows impaired neuropsychological performance as a result of HIV-mediated neuroinflammation and eventual central nervous system (CNS) injury. CNS compartmentalization of HIV, coupled with the evolution of genetically isolated populations in the CNS, is responsible for poor prognosis in patients with AIDS, warranting further investigation and possible additions to the current therapeutic strategy. This chapter reviews key advances in the field of neuropathogenesis and studies that have highlighted how molecular diversity within the HIV genome may impact HIV-associated neurologic disease. We also discuss the possible functional implications of genetic variation within the viral promoter and possibly other regions of the viral genome, especially in the cells of monocyte-macrophage lineage, which are arguably key cellular players in HIV-associated CNS disease.
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Affiliation(s)
- Satinder Dahiya
- Department of Microbiology and Immunology, Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Bryan P Irish
- Department of Microbiology and Immunology, Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Michael R Nonnemacher
- Department of Microbiology and Immunology, Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Brian Wigdahl
- Department of Microbiology and Immunology, Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
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Iijima K, Okudaira N, Tamura M, Doi A, Saito Y, Shimura M, Goto M, Matsunaga A, Kawamura YI, Otsubo T, Dohi T, Hoshino S, Kano S, Hagiwara S, Tanuma J, Gatanaga H, Baba M, Iguchi T, Yanagita M, Oka S, Okamura T, Ishizaka Y. Viral protein R of human immunodeficiency virus type-1 induces retrotransposition of long interspersed element-1. Retrovirology 2013; 10:83. [PMID: 23915234 PMCID: PMC3751050 DOI: 10.1186/1742-4690-10-83] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Accepted: 07/18/2013] [Indexed: 01/04/2023] Open
Abstract
Background Viral protein R (Vpr), a protein of human immunodeficiency virus type-1 (HIV-1) with various biological functions, was shown to be present in the blood of HIV-1-positive patients. However, it remained unclear whether circulating Vpr in patients’ blood is biologically active. Here, we examined the activity of blood Vpr using an assay system by which retrotransposition of long interspersed element-1 (L1-RTP) was detected. We also investigated the in vivo effects of recombinant Vpr (rVpr) by administrating it to transgenic mice harboring human L1 as a transgene (hL1-Tg mice). Based on our data, we discuss the involvement of blood Vpr in the clinical symptoms of acquired immunodeficiency syndrome (AIDS). Results We first discovered that rVpr was active in induction of L1-RTP. Biochemical analyses revealed that rVpr-induced L1-RTP depended on the aryl hydrocarbon receptor, mitogen-activated protein kinases, and CCAAT/enhancer-binding protein β. By using a sensitive L1-RTP assay system, we showed that 6 of the 15 blood samples from HIV-1 patients examined were positive for induction of L1-RTP. Of note, the L1-RTP-inducing activity was blocked by a monoclonal antibody specific for Vpr. Moreover, L1-RTP was reproducibly induced in various organs, including the kidney, when rVpr was administered to hL1-Tg mice. Conclusions Blood Vpr is biologically active, suggesting that its monitoring is worthwhile for clarification of the roles of Vpr in the pathogenesis of AIDS. This is the first report to demonstrate a soluble factor in patients’ blood active for L1-RTP activity, and implies the involvement of L1-RTP in the development of human diseases.
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Affiliation(s)
- Kenta Iijima
- Department of Intractable Diseases, Research Institute, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655, Japan
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Cortisol patterns are associated with T cell activation in HIV. PLoS One 2013; 8:e63429. [PMID: 23922644 PMCID: PMC3724863 DOI: 10.1371/journal.pone.0063429] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2012] [Accepted: 04/04/2013] [Indexed: 11/25/2022] Open
Abstract
Objective The level of T cell activation in untreated HIV disease is strongly and independently associated with risk of immunologic and clinical progression. The factors that influence the level of activation, however, are not fully defined. Since endogenous glucocorticoids are important in regulating inflammation, we sought to determine whether less optimal diurnal cortisol patterns are associated with greater T cell activation. Methods We studied 128 HIV-infected adults who were not on treatment and had a CD4+ T cell count above 250 cells/µl. We assessed T cell activation by CD38 expression using flow cytometry, and diurnal cortisol was assessed with salivary measurements. Results Lower waking cortisol levels correlated with greater T cell immune activation, measured by CD38 mean fluorescent intensity, on CD4+ T cells (r = −0.26, p = 0.006). Participants with lower waking cortisol also showed a trend toward greater activation on CD8+ T cells (r = −0.17, p = 0.08). A greater diurnal decline in cortisol, usually considered a healthy pattern, correlated with less CD4+ (r = 0.24, p = 0.018) and CD8+ (r = 0.24, p = 0.017) activation. Conclusions These data suggest that the hypothalamic-pituitary-adrenal (HPA) axis contributes to the regulation of T cell activation in HIV. This may represent an important pathway through which psychological states and the HPA axis influence progression of HIV.
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Shrivastav S, Zhang L, Okamoto K, Lee H, Lagranha C, Abe Y, Balasubramanyam A, Lopaschuk GD, Kino T, Kopp JB. HIV-1 Vpr enhances PPARβ/δ-mediated transcription, increases PDK4 expression, and reduces PDC activity. Mol Endocrinol 2013; 27:1564-76. [PMID: 23842279 DOI: 10.1210/me.2012-1370] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
HIV infection and its therapy are associated with disorders of lipid metabolism and bioenergetics. Previous work has suggested that viral protein R (Vpr) may contribute to the development of lipodystrophy and insulin resistance observed in HIV-1-infected patients. In adipocytes, Vpr suppresses mRNA expression of peroxisomal proliferator-activating receptor-γ (PPARγ)-responsive genes and inhibits differentiation. We investigated whether Vpr might interact with PPARβ/δ and influence its transcriptional activity. In the presence of PPARβ/δ, Vpr induced a 3.3-fold increase in PPAR response element-driven transcriptional activity, a 1.9-fold increase in pyruvate dehydrogenase kinase 4 (PDK4) protein expression, and a 1.6-fold increase in the phosphorylated pyruvate dehydrogenase subunit E1α leading to a 47% decrease in the activity of the pyruvate dehydrogenase complex in HepG2 cells. PPARβ/δ knockdown attenuated Vpr-induced enhancement of endogenous PPARβ/δ-responsive PDK4 mRNA expression. Vpr induced a 1.3-fold increase in mRNA expression of both carnitine palmitoyltransferase I (CPT1) and acetyl-coenzyme A acyltransferase 2 (ACAA2) and doubled the activity of β-hydroxylacyl coenzyme A dehydrogenase (HADH). Vpr physically interacted with the ligand-binding domain of PPARβ/δ in vitro and in vivo. Consistent with a role in energy expenditure, Vpr increased state-3 respiration in isolated mitochondria (1.16-fold) and basal oxygen consumption rate in intact HepG2 cells (1.2-fold) in an etomoxir-sensitive manner, indicating that the oxygen consumption rate increase is β-oxidation-dependent. The effects of Vpr on PPAR response element activation, pyruvate dehydrogenase complex activity, and β-oxidation were reversed by specific PPARβ/δ antagonists. These results support the hypothesis that Vpr contributes to impaired energy metabolism and increased energy expenditure in HIV patients.
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Affiliation(s)
- Shashi Shrivastav
- Kidney Disease Section, National Institute of Diabetes and Digestive andKidney Diseases, National Institutes of Health,Bethesda, Maryland 20892-1268, USA
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Vu CN, Ruiz-Esponda R, Yang E, Chang E, Gillard B, Pownall HJ, Hoogeveen RC, Coraza I, Balasubramanyam A. Altered relationship of plasma triglycerides to HDL cholesterol in patients with HIV/HAART-associated dyslipidemia: further evidence for a unique form of metabolic syndrome in HIV patients. Metabolism 2013; 62:1014-20. [PMID: 23522788 PMCID: PMC3691339 DOI: 10.1016/j.metabol.2013.01.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 01/22/2013] [Accepted: 01/23/2013] [Indexed: 11/20/2022]
Abstract
INTRODUCTION Plasma triglycerides (TG) and HDL-C are inversely related in Metabolic Syndrome (MetS), due to exchange of VLDL-TG for HDL-cholesteryl esters catalyzed by cholesteryl ester transfer protein (CETP). We investigated the relationship of TG to HDL-C in highly-active antiretroviral drug (HAART)-treated HIV patients. METHODS Fasting plasma TG and HDL-C levels were compared in 179 hypertriglyceridemic HIV/HAART patients and 71 HIV-negative persons (31 normotriglyceridemic (NL) and 40 hypertriglyceridemic due to type IV hyperlipidemia (HTG)). CETP mass and activity were compared in 19 NL and 87 HIV/HAART subjects. RESULTS Among the three groups, a plot of HDL-C vs. TG gave similar slopes but significantly different y-intercepts (9.24±0.45, 8.16±0.54, 6.70±0.65, sqrt(HDL-C) for NL, HIV and HTG respectively; P<0.001); this difference persisted after adjusting HDL-C for TG, age, BMI, gender, glucose, CD4 count, viral load and HAART strata (7.18±0.20, 6.20±0.05 and 4.55±0.15 sqrt(HDL-C) for NL, HIV and HTG, respectively, P<0.001). CETP activity was not different between NL and HIV, but CETP mass was significantly higher in HIV (1.47±0.53 compared to 0.93±0.27μg/mL, P<0.0001), hence CETP specific activity was lower in HIV (22.67±13.46 compared to 28.46±8.24nmol/μg/h, P=0.001). CONCLUSIONS Dyslipidemic HIV/HAART patients have a distinctive HDL-C plasma concentration adjusted for TG. The weak inverse relationship between HDL-C and TG is not explained by altered total CETP activity; it could result from a non-CETP-dependent mechanism or a decrease in CETP function due to inhibitors of CETP activity in HIV patients' plasma.
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Affiliation(s)
- Catherine N. Vu
- Translational Metabolism Unit, Diabetes Research Center, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, Texas
| | - Raul Ruiz-Esponda
- Translational Metabolism Unit, Diabetes Research Center, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, Texas
| | - Eric Yang
- Section of Atherosclerosis and Lipoprotein Research, Baylor College of Medicine, Houston, Texas
| | - Evelyn Chang
- Translational Metabolism Unit, Diabetes Research Center, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, Texas
| | - Baiba Gillard
- Section of Atherosclerosis and Lipoprotein Research, Baylor College of Medicine, Houston, Texas
| | - Henry J. Pownall
- Section of Atherosclerosis and Lipoprotein Research, Baylor College of Medicine, Houston, Texas
| | - Ron C. Hoogeveen
- Section of Atherosclerosis and Lipoprotein Research, Baylor College of Medicine, Houston, Texas
| | - Ivonne Coraza
- Translational Metabolism Unit, Diabetes Research Center, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, Texas
| | - Ashok Balasubramanyam
- Translational Metabolism Unit, Diabetes Research Center, Division of Diabetes, Endocrinology and Metabolism, Baylor College of Medicine, Houston, Texas
- Endocrine Service, Ben Taub General Hospital, Houston, TX
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George MM, Bhangoo A. Human immune deficiency virus (HIV) infection and the hypothalamic pituitary adrenal axis. Rev Endocr Metab Disord 2013; 14:105-12. [PMID: 23728720 DOI: 10.1007/s11154-013-9244-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The hypothalamic pituitary adrenal (HPA) axis is the most common of the endocrine lines/axis' to be affected by HIV infection. There are multiple factors that contribute to this HPA axis dysregulation. Direct invasion of the various organs in the axis can be either by opportunistic infections or infiltrative diseases. The soluble factors or cytokines released during viral infection and the chronic inflammatory state that follows, also contribute to these alterations. The actions of these cytokines released by the immune response can both activate the HPA axis and cause a glucocorticoid resistant state. Further, many of the anti-retroviral and other medications used to treat HIV infection can contribute to HPA axis dysfunction. While the diagnosis and treatment of endocrine dysfunction is the same as in any other patient, management pathways may be quite different. While some may be adaptive responses, life threatening adrenal insufficiency can also be present. It is important the latter be picked up expeditiously and treated promptly to avoid mortality.
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Affiliation(s)
- Minu M George
- Department of Pediatrics, Section of Pediatric Endocrinology and Diabetes, The University of Oklahoma College of Medicine, Oklahoma City, OK, USA
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Tomasicchio M, Avenant C, Du Toit A, Ray RM, Hapgood JP. The progestin-only contraceptive medroxyprogesterone acetate, but not norethisterone acetate, enhances HIV-1 Vpr-mediated apoptosis in human CD4+ T cells through the glucocorticoid receptor. PLoS One 2013; 8:e62895. [PMID: 23658782 PMCID: PMC3643923 DOI: 10.1371/journal.pone.0062895] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 03/26/2013] [Indexed: 12/25/2022] Open
Abstract
The glucocorticoid receptor (GR) regulates several physiological functions, including immune function and apoptosis. The HIV-1 virus accessory protein, viral protein R (Vpr), can modulate the transcriptional response of the GR. Glucocorticoids (GCs) and Vpr have been reported to induce apoptosis in various cells, including T-cells. We have previously shown that the injectable contraceptive, medroxyprogesterone acetate (MPA) is a partial to full agonist for the GR, unlike norethisterone acetate (NET-A). We investigated the functional cross talk between the GR and Vpr in inducing apoptosis in CD4(+) T-cells, in the absence and presence of GCs and these progestins, as well as progesterone. By using flow cytometry, we show that, in contrast to NET-A and progesterone, the synthetic GR ligand dexamethasone (Dex), cortisol and MPA induce apoptosis in primary CD4(+) T-cells. Furthermore, the C-terminal part of the Vpr peptide, or HIV-1 pseudovirus, together with Dex or MPA further increased the apoptotic phenotype, unlike NET-A and progesterone. By a combination of Western blotting, PCR and the use of receptor- selective agonists, we provide evidence that the GR and the estrogen receptor are the only steroid receptors expressed in peripheral blood mononuclear cells. These results, together with the findings that RU486, a GR antagonist, prevents Dex-, MPA- and Vpr-mediated apoptosis, provide evidence for the first time that GR agonists or partial agonists increase apoptosis in primary CD4(+) T-cells via the GR. We show that apoptotic induction involves differential expression of key apoptotic genes by both Vpr and GCs/MPA. This work suggests that contraceptive doses of MPA but not NET-A or physiological doses of progesterone could potentially accelerate depletion of CD4(+) T-cells in a GR-dependent fashion in HIV-1 positive women, thereby contributing to immunodeficiency. The results imply that choice of progestin used in contraception may be critical to susceptibility and progression of diseases such as HIV-1.
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Affiliation(s)
- Michele Tomasicchio
- Department of Molecular and Cell Biology, University of Cape Town, Cape Town, Western Province, South Africa
| | - Chanel Avenant
- Department of Molecular and Cell Biology, University of Cape Town, Cape Town, Western Province, South Africa
| | - Andrea Du Toit
- Department of Molecular and Cell Biology, University of Cape Town, Cape Town, Western Province, South Africa
| | - Roslyn M. Ray
- Department of Molecular and Cell Biology, University of Cape Town, Cape Town, Western Province, South Africa
| | - Janet P. Hapgood
- Department of Molecular and Cell Biology, University of Cape Town, Cape Town, Western Province, South Africa
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Abstract
Leptin therapy in human recombinant form has recently been used in HIV-associated lipodystrophy syndrome on experimental basis in some small short-term clinical trials. It has shown its beneficial effects only in hypoleptinemic HIV-infected patients by causing definite improvement in their insulin sensitivity, glucose tolerance, lipid status, and truncal obesity. Leptin prevents lipotoxicity and activates insulin signaling pathways through several postulated mechanisms. Central leptin insufficiency with peripheral hyperleptinemia has come out to be a significant contributor to the development of obesity and metabolic syndrome. In this article, we will review the basis of leptin therapy in HIV patients, with its promises. However, further larger clinical trials are needed to prove its long-term efficacy in the control of metabolic complications related to HIV therapy.
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Affiliation(s)
- Uma Sinha
- Department of Medicine, Nilratan Sircar Medical College, Kolkata, India
| | - Keshab Sinharay
- Department of Medicine, Nilratan Sircar Medical College, Kolkata, India
| | - Nilanjan Sengupta
- Department of Endocrinology, Nilratan Sircar Medical College, Kolkata, India
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Kino T, Pavlatou MG, Moraitis AG, Nemery RL, Raygada M, Stratakis CA. ZNF764 haploinsufficiency may explain partial glucocorticoid, androgen, and thyroid hormone resistance associated with 16p11.2 microdeletion. J Clin Endocrinol Metab 2012; 97:E1557-66. [PMID: 22577170 PMCID: PMC3410270 DOI: 10.1210/jc.2011-3493] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Nuclear hormone receptors exert their transcriptional effects through shared cofactor molecules; thus, defects in such intermediate proteins may be associated with multiple hormone resistance. Microdeletion of small chromosomal segments results in hereditary or sporadic diseases by affecting expression of residing genes. OBJECTIVES We describe a 7-yr-old boy with partial resistance to glucocorticoids, thyroid hormones, and possibly androgens. He was diagnosed as being in the autism spectrum disorder and had developmental delay and several facial morphological manifestations. We explored genes responsible for multiple hormone resistance of this case. RESULTS We found in this patient an approximately 1.1-Mb heterozygous 16p11.2 microdeletion, which included an approximately 500-kb unique deletion along with the common, previously reported approximately 600-kb 16p11.2 microdeletion. The small interfering RNA-based screening revealed that knockdown of ZNF764, which is located in the deleted segment unique to our case, significantly reduced glucocorticoid-, androgen-, and thyroid hormone-induced transcriptional activity of their responsive genes in HeLa cells, whereas its overexpression enhanced their transcriptional activity. The activities of the estrogen and progesterone receptors, cAMP response element-binding protein, and p53 were not affected in these cells. ZNF764 (zinc finger protein 764) expression was reduced in the patient's peripheral blood mononuclear cells, whereas exogenously supplemented ZNF764 recovered responsiveness to glucocorticoids in the patient's Epstein-Barr virus-transformed lymphocytes. The effect of ZNF764 on the glucocorticoid receptor transcriptional activity was mediated through cooperation with a general nuclear hormone receptor coactivator, transcriptional intermediary factor 1. CONCLUSIONS ZNF764 haploinsufficiency caused by microdeletion may be responsible for the partial multiple hormone resistance observed in our patient. ZNF764 appears to be involved in glucocorticoid, androgen, and thyroid hormone action.
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Affiliation(s)
- Tomoshige Kino
- Unit on Molecular Hormone Actio, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892-1109, USA.
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Dahiya S, Nonnemacher MR, Wigdahl B. Deployment of the human immunodeficiency virus type 1 protein arsenal: combating the host to enhance viral transcription and providing targets for therapeutic development. J Gen Virol 2012; 93:1151-1172. [PMID: 22422068 DOI: 10.1099/vir.0.041186-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Despite the success of highly active antiretroviral therapy in combating human immunodeficiency virus type 1 (HIV-1) infection, the virus still persists in viral reservoirs, often in a state of transcriptional silence. This review focuses on the HIV-1 protein and regulatory machinery and how expanding knowledge of the function of individual HIV-1-coded proteins has provided valuable insights into understanding HIV transcriptional regulation in selected susceptible cell types. Historically, Tat has been the most studied primary transactivator protein, but emerging knowledge of HIV-1 transcriptional regulation in cells of the monocyte-macrophage lineage has more recently established that a number of the HIV-1 accessory proteins like Vpr may directly or indirectly regulate the transcriptional process. The viral proteins Nef and matrix play important roles in modulating the cellular activation pathways to facilitate viral replication. These observations highlight the cross talk between the HIV-1 transcriptional machinery and cellular activation pathways. The review also discusses the proposed transcriptional regulation mechanisms that intersect with the pathways regulated by microRNAs and how development of the knowledge of chromatin biology has enhanced our understanding of key protein-protein and protein-DNA interactions that form the HIV-1 transcriptome. Finally, we discuss the potential pharmacological approaches to target viral persistence and enhance effective transcription to purge the virus in cellular reservoirs, especially within the central nervous system, and the novel therapeutics that are currently in various stages of development to achieve a much superior prognosis for the HIV-1-infected population.
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Affiliation(s)
- Satinder Dahiya
- Department of Microbiology and Immunology, Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Michael R Nonnemacher
- Department of Microbiology and Immunology, Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Brian Wigdahl
- Department of Microbiology and Immunology, Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA 19129, USA
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Miller MS, Mymryk JS. An unhealthy relationship: viral manipulation of the nuclear receptor superfamily. Future Microbiol 2011; 6:999-1019. [PMID: 21958141 DOI: 10.2217/fmb.11.80] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The nuclear receptor (NR) superfamily is a diverse group of over 50 proteins whose function is to regulate the transcription of a vast array of cellular genes. These proteins are able to tune transcription over an extremely dynamic range due to the fact that they may act as either transcriptional activators or repressors depending on promoter context and ligand status. Due to these unique properties, diverse families of viruses have evolved strategies to exploit NRs in order to regulate expression of their own genes and to optimize the cellular milieu to facilitate the viral lifecycle. While the specific NRs targeted by these viruses vary, the strategies used to target them are common. This is accomplished at the cis-level by incorporation of nuclear receptor response elements into the viral genome and at the trans-level by viral proteins that target NRs directly or indirectly to modulate their function. The specific NR(s) targeted by a particular virus are likely to be reflective of the tissue tropism of the virus in question. Thus, the essential role played by NRs in the replication cycles of such diverse viruses underscores the importance of understanding their functions in the context of specific infections. This knowledge will allow appropriate considerations to be made when treating infected individuals with hormone-associated diseases and will potentially assist in the rational design of novel antiviral therapeutics.
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Affiliation(s)
- Matthew S Miller
- Department of Microbiology & Immunology, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, Ontario, N6A 5C1, Canada
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Abstract
PURPOSE OF REVIEW This review addresses our current understanding of the pathogenesis of HIV-associated lipohypertrophy and describes an evidence-based approach to treatment. RECENT FINDINGS Although the pathogenesis of HIV-associated lipohypertrophy remains elusive, recent clinical and laboratory investigations in fatty acid metabolism and growth hormone dynamics have furthered our understanding of the condition. These findings have also paved the way for new therapeutic interventions, of which tesamorelin, an analog of growth hormone-releasing hormone (GHRH), has gained recognition as a promising treatment strategy against visceral fat accumulation. Recent randomized placebo-controlled trials of tesamorelin demonstrated significant reductions in visceral adipose tissue, improvement in lipid parameters, and minimal adverse effects on glucose tolerance. Optimal therapeutic dosing and treatment duration, though, are not yet known. Whether treatment with GHRH-analogs will translate into improved long-term metabolic and cardiovascular outcomes also remains to be seen. SUMMARY Although the pathogenesis of HIV lipohypertrophy remains unclear, several theories and observations have led to the development of treatment strategies to counter fat accumulation and its accompanying metabolic complications. Based on clinical trials, analogs of the growth hormone (GH)/GHRH axis appear to be most effective in reducing visceral adipose tissue.
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Kogan M, Rappaport J. HIV-1 accessory protein Vpr: relevance in the pathogenesis of HIV and potential for therapeutic intervention. Retrovirology 2011; 8:25. [PMID: 21489275 PMCID: PMC3090340 DOI: 10.1186/1742-4690-8-25] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Accepted: 04/13/2011] [Indexed: 01/11/2023] Open
Abstract
The HIV protein, Vpr, is a multifunctional accessory protein critical for efficient viral infection of target CD4+ T cells and macrophages. Vpr is incorporated into virions and functions to transport the preintegration complex into the nucleus where the process of viral integration into the host genome is completed. This action is particularly important in macrophages, which as a result of their terminal differentiation and non-proliferative status, would be otherwise more refractory to HIV infection. Vpr has several other critical functions including activation of HIV-1 LTR transcription, cell-cycle arrest due to DCAF-1 binding, and both direct and indirect contributions to T-cell dysfunction. The interactions of Vpr with molecular pathways in the context of macrophages, on the other hand, support accumulation of a persistent reservoir of HIV infection in cells of the myeloid lineage. The role of Vpr in the virus life cycle, as well as its effects on immune cells, appears to play an important role in the immune pathogenesis of AIDS and the development of HIV induced end-organ disease. In view of the pivotal functions of Vpr in virus infection, replication, and persistence of infection, this protein represents an attractive target for therapeutic intervention.
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Affiliation(s)
- Michael Kogan
- Department of Neuroscience, Department of Neuroscience, Center for Neurovirology, Temple University School of Medicine, 3500 North Broad Street, Philadelphia, PA 19140, USA
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Nader N, Ng SSM, Lambrou GI, Pervanidou P, Wang Y, Chrousos GP, Kino T. AMPK regulates metabolic actions of glucocorticoids by phosphorylating the glucocorticoid receptor through p38 MAPK. Mol Endocrinol 2010; 24:1748-64. [PMID: 20660302 DOI: 10.1210/me.2010-0192] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Glucocorticoids play central roles in the regulation of energy metabolism by shifting it toward catabolism, whereas AMP-activated protein kinase (AMPK) is the master regulator of energy homeostasis, sensing energy depletion and stimulating pathways of increasing fuel uptake and saving on peripheral supplies. We showed here that AMPK regulates glucocorticoid actions on carbohydrate metabolism by targeting the glucocorticoid receptor (GR) and modifying transcription of glucocorticoid-responsive genes in a tissue- and promoter-specific fashion. Activation of AMPK in rats reversed glucocorticoid-induced hepatic steatosis and suppressed glucocorticoid-mediated stimulation of glucose metabolism. Transcriptomic analysis in the liver suggested marked overlaps between the AMPK and glucocorticoid signaling pathways directed mostly from AMPK to glucocorticoid actions. AMPK accomplishes this by phosphorylating serine 211 of the human GR indirectly through phosphorylation and consequent activation of p38 MAPK and by altering attraction of transcriptional coregulators to DNA-bound GR. In human peripheral mononuclear cells, AMPK mRNA expression positively correlated with that of glucocorticoid-responsive glucocorticoid-inducible leucine zipper protein, which correlated also positively with the body mass index of subjects. These results indicate that the AMPK-mediated energy control system modulates glucocorticoid action at target tissues. Because increased action of glucocorticoids is associated with the development of metabolic disorders, activation of AMPK could be a promising target for developing pharmacological interventions to these pathologies.
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Affiliation(s)
- Nancy Nader
- Unit on Molecular Hormone Action, Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Building 10, Clinical Research Center, Room 1-3140, 10 Center Drive MSC 1109, Bethesda, MD 20892-1109, USA
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Toll-like receptor control of glucocorticoid-induced apoptosis in human plasmacytoid predendritic cells (pDCs). Blood 2010; 116:3389-97. [PMID: 20592251 DOI: 10.1182/blood-2010-05-282913] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microbial infection triggers the endogenous production of immunosuppressive glucocorticoid (GC) hormones and simultaneously activates innate immunity through toll-like receptors (TLRs). How innate immune cells integrate these 2 opposing signals in dictating immunity or tolerance to infection is not known. In this study, we show that human plasmacytoid predendritic cells (pDCs) were highly sensitive to GC-induced apoptosis. Strikingly, they were protected by microbial stimulation through TLR-7 and TLR-9, but not by microbial-independent stimuli, such as interleukin-3, granulocyte macrophage colony-stimulating factor, or CD40-ligand. This protection was dependent on TLR-induced autocrine tumor necrosis factor-α and interferon-α, which collectively increased the expression ratio between antiapoptotic genes (Bcl-2, Bcl-xL, BIRC3, CFLAR) versus proapoptotic genes (Caspase-8, BID, BAD, BAX). In particular, virus-induced Bcl-2 up-regulation was dependent on autocrine interferon-α. Using small interfering RNA technology, we demonstrated that Bcl-2 and CFLAR/c-flip were essential for TLR-induced protection of pDCs from GC-induced caspase-8-mediated apoptosis. Our results demonstrate a novel property of the TLR pathway in regulating the interface between GC and innate immunity and reveal a previously undescribed mechanism of GC resistance.
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