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Davis SE, Cirincione AB, Jimenez-Torres AC, Zhu J. The Impact of Neurotransmitters on the Neurobiology of Neurodegenerative Diseases. Int J Mol Sci 2023; 24:15340. [PMID: 37895020 PMCID: PMC10607327 DOI: 10.3390/ijms242015340] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 10/16/2023] [Accepted: 10/17/2023] [Indexed: 10/29/2023] Open
Abstract
Neurodegenerative diseases affect millions of people worldwide. Neurodegenerative diseases result from progressive damage to nerve cells in the brain or peripheral nervous system connections that are essential for cognition, coordination, strength, sensation, and mobility. Dysfunction of these brain and nerve functions is associated with Alzheimer's disease, Parkinson's disease, Huntington's disease, Amyotrophic lateral sclerosis, and motor neuron disease. In addition to these, 50% of people living with HIV develop a spectrum of cognitive, motor, and/or mood problems collectively referred to as HIV-Associated Neurocognitive Disorders (HAND) despite the widespread use of a combination of antiretroviral therapies. Neuroinflammation and neurotransmitter systems have a pathological correlation and play a critical role in developing neurodegenerative diseases. Each of these diseases has a unique pattern of dysregulation of the neurotransmitter system, which has been attributed to different forms of cell-specific neuronal loss. In this review, we will focus on a discussion of the regulation of dopaminergic and cholinergic systems, which are more commonly disturbed in neurodegenerative disorders. Additionally, we will provide evidence for the hypothesis that disturbances in neurotransmission contribute to the neuronal loss observed in neurodegenerative disorders. Further, we will highlight the critical role of dopamine as a mediator of neuronal injury and loss in the context of NeuroHIV. This review will highlight the need to further investigate neurotransmission systems for their role in the etiology of neurodegenerative disorders.
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Affiliation(s)
| | | | | | - Jun Zhu
- Department of Drug Discovery and Biomedical Sciences, College of Pharmacy, University of South Carolina, 715 Sumter Street, Columbia, SC 29208, USA; (S.E.D.); (A.B.C.); (A.C.J.-T.)
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2
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Namba MD, Xie Q, Barker JM. Advancing the preclinical study of comorbid neuroHIV and substance use disorders: Current perspectives and future directions. Brain Behav Immun 2023; 113:453-475. [PMID: 37567486 PMCID: PMC10528352 DOI: 10.1016/j.bbi.2023.07.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 06/23/2023] [Accepted: 07/30/2023] [Indexed: 08/13/2023] Open
Abstract
Human immunodeficiency virus (HIV) remains a persistent public health concern throughout the world. Substance use disorders (SUDs) are a common comorbidity that can worsen treatment outcomes for people living with HIV. The relationship between HIV infection and SUD outcomes is likely bidirectional, making clear interrogation of neurobehavioral outcomes challenging in clinical populations. Importantly, the mechanisms through which HIV and addictive drugs disrupt homeostatic immune and CNS function appear to be highly overlapping and synergistic within HIV-susceptible reward and motivation circuitry in the central nervous system. Decades of animal research have revealed invaluable insights into mechanisms underlying the pathophysiology SUDs and HIV, although translational studies examining comorbid SUDs and HIV are very limited due to the technical challenges of modeling HIV infection preclinically. In this review, we discuss preclinical animal models of HIV and highlight key pathophysiological characteristics of each model, with a particular emphasis on rodent models of HIV. We then review the implementation of these models in preclinical SUD research and identify key gaps in knowledge in the field. Finally, we discuss how cutting-edge behavioral neuroscience tools, which have revealed key insights into the neurobehavioral mechanisms of SUDs, can be applied to preclinical animal models of HIV to reveal potential, novel treatment avenues for comorbid HIV and SUDs. Here, we argue that future preclinical SUD research would benefit from incorporating comorbidities such as HIV into animal models and would facilitate the discovery of more refined, subpopulation-specific mechanisms and effective SUD prevention and treatment targets.
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Affiliation(s)
- Mark D Namba
- Department of Pharmacology & Physiology, College of Medicine, Drexel University, Philadelphia, PA, USA
| | - Qiaowei Xie
- Department of Pharmacology & Physiology, College of Medicine, Drexel University, Philadelphia, PA, USA
| | - Jacqueline M Barker
- Department of Pharmacology & Physiology, College of Medicine, Drexel University, Philadelphia, PA, USA.
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3
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Liu X, Tang SJ. Pathogenic mechanisms of human immunodeficiency virus (HIV)-associated pain. Mol Psychiatry 2023; 28:3613-3624. [PMID: 37857809 DOI: 10.1038/s41380-023-02294-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 09/25/2023] [Accepted: 10/05/2023] [Indexed: 10/21/2023]
Abstract
Chronic pain is a prevalent neurological complication among individuals living with human immunodeficiency virus (PLHIV) in the post-combination antiretroviral therapy (cART) era. These individuals experience malfunction in various cellular and molecular pathways involved in pain transmission and modulation, including the neuropathology of the peripheral sensory neurons and neurodegeneration and neuroinflammation in the spinal dorsal horn. However, the underlying etiologies and mechanisms leading to pain pathogenesis are complex and not fully understood. In this review, we aim to summarize recent progress in this field. Specifically, we will begin by examining neuropathology in the pain pathways identified in PLHIV and discussing potential causes, including those directly related to HIV-1 infection and comorbidities, such as antiretroviral drug use. We will also explore findings from animal models that may provide insights into the molecular and cellular processes contributing to neuropathology and chronic pain associated with HIV infection. Emerging evidence suggests that viral proteins and/or antiretroviral drugs trigger a complex pathological cascade involving neurons, glia, and potentially non-neural cells, and that interactions between these cells play a critical role in the pathogenesis of HIV-associated pain.
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Affiliation(s)
- Xin Liu
- Stony Brook University Pain and Analgesia Research Center (SPARC), Stony Brook University, Stony Brook, 11794, NY, USA
- Department of Anesthesiology, Renaissance School of Medicine, Stony Brook University, Stony Brook, 11794, NY, USA
| | - Shao-Jun Tang
- Stony Brook University Pain and Analgesia Research Center (SPARC), Stony Brook University, Stony Brook, 11794, NY, USA.
- Department of Anesthesiology, Renaissance School of Medicine, Stony Brook University, Stony Brook, 11794, NY, USA.
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4
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Fu R, Jinnah H, Mckay JL, Miller AH, Felger JC, Farber EW, Sharma S, Whicker N, Moore RC, Franklin D, Letendre SL, Anderson AM. Cerebrospinal fluid levels of 5-HIAA and dopamine in people with HIV and depression. J Neurovirol 2023; 29:440-448. [PMID: 37289360 PMCID: PMC10766341 DOI: 10.1007/s13365-023-01142-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 04/17/2023] [Accepted: 04/24/2023] [Indexed: 06/09/2023]
Abstract
Depression is a common illness in people with HIV (PWH) and is associated with substantial morbidity and mortality. The mechanisms that underpin depression in PWH remain incompletely elucidated, and more research is therefore needed to develop effective treatments. One hypothesis is that neurotransmitter levels may be altered. These levels could be influenced by the chronic inflammation and viral persistence that occurs in PWH. We examined a panel of cerebrospinal fluid (CSF) neurotransmitters in PWH on suppressive antiretroviral therapy (ART), many of whom had a current depression diagnosis. CSF monoamine neurotransmitters and their metabolites were measured from participants in studies at the Emory Center for AIDS Research (CFAR). Only participants on stable ART with suppressed HIV RNA from both plasma and CSF were analyzed. Neurotransmitter levels were measured with high-performance liquid chromatography (HPLC). Neurotransmitters and their metabolites included dopamine (DA), homovanillic acid (HVA, a major metabolite of dopamine), serotonin (5-HT), 5-hydroxyindole-3-acetic acid (5-HIAA, a major metabolite of serotonin), and 4-hydroxy-3-methoxyphenylglycol (MHPG, a major metabolite of norepinephrine). Multivariable logistic regression was used to evaluate factors associated with depression. There were 79 PWH with plasma and CSF HIV RNA levels < 200 copies/mL at the time of the visit, and 25 (31.6%) carried a current diagnosis of depression. Participants with depression were significantly older (median age 53 years versus 47 years, P = 0.014) and were significantly less likely to be African American (48.0% versus 77.8%, P = 0.008). Participants with depression had significantly lower dopamine levels (median 0.49 ng/mL versus 0.62 ng/mL, P = 0.03) and significantly lower 5-HIAA levels (median 12.57 ng/mL versus 15.41 ng/mL, P = 0.015). Dopamine and 5-HIAA were highly correlated. In the multivariable logistic regression models, lower 5-HIAA was significantly associated with the depression diagnosis when accounting for other significant demographic factors. The associations between lower 5-HIAA, lower dopamine, and depression in PWH suggest that altered neurotransmission may contribute to these comorbid conditions. However, the effects of antidepressants on neurotransmitters cannot be ruled out as a factor in the 5-HIAA results.
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Affiliation(s)
- Rong Fu
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, Atlanta, GA, USA
| | - Hyder Jinnah
- Department of Neurology, Human Genetics and Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - J Lucas Mckay
- Department of Biomedical Informatics, Emory University, Atlanta, GA, USA
| | - Andrew H Miller
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Jennifer C Felger
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Eugene W Farber
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Sanjay Sharma
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Neil Whicker
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Raeanne C Moore
- Department of Psychiatry, University of California at San Diego School of Medicine, La Jolla, San Diego, CA, USA
| | - Donald Franklin
- Department of Psychiatry, University of California at San Diego School of Medicine, La Jolla, San Diego, CA, USA
| | - Scott L Letendre
- Department of Medicine, University of California at San Diego School of Medicine, La Jolla, San Diego, CA, USA
| | - Albert M Anderson
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA.
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5
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Sonti S, Tyagi K, Pande A, Daniel R, Sharma AL, Tyagi M. Crossroads of Drug Abuse and HIV Infection: Neurotoxicity and CNS Reservoir. Vaccines (Basel) 2022; 10:vaccines10020202. [PMID: 35214661 PMCID: PMC8875185 DOI: 10.3390/vaccines10020202] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/18/2022] [Accepted: 01/25/2022] [Indexed: 01/27/2023] Open
Abstract
Drug abuse is a common comorbidity in people infected with HIV. HIV-infected individuals who abuse drugs are a key population who frequently experience suboptimal outcomes along the HIV continuum of care. A modest proportion of HIV-infected individuals develop HIV-associated neurocognitive issues, the severity of which further increases with drug abuse. Moreover, the tendency of the virus to go into latency in certain cellular reservoirs again complicates the elimination of HIV and HIV-associated illnesses. Antiretroviral therapy (ART) successfully decreased the overall viral load in infected people, yet it does not effectively eliminate the virus from all latent reservoirs. Although ART increased the life expectancy of infected individuals, it showed inconsistent improvement in CNS functioning, thus decreasing the quality of life. Research efforts have been dedicated to identifying common mechanisms through which HIV and drug abuse lead to neurotoxicity and CNS dysfunction. Therefore, in order to develop an effective treatment regimen to treat neurocognitive and related symptoms in HIV-infected patients, it is crucial to understand the involved mechanisms of neurotoxicity. Eventually, those mechanisms could lead the way to design and develop novel therapeutic strategies addressing both CNS HIV reservoir and illicit drug use by HIV patients.
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Affiliation(s)
- Shilpa Sonti
- Center for Translational Medicine, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA 19107, USA; (S.S.); (A.L.S.)
| | - Kratika Tyagi
- Department of Biotechnology, Banasthali Vidyapith, Vanasthali, Jaipur 304022, Rajasthan, India;
| | - Amit Pande
- Cell Culture Laboratory, ICAR-Directorate of Coldwater Fisheries Research, Bhimtal, Nainital 263136, Uttarakhand, India;
| | - Rene Daniel
- Farber Hospitalist Service, Department of Neurological Surgery, Thomas Jefferson University, Philadelphia, PA 19107, USA;
| | - Adhikarimayum Lakhikumar Sharma
- Center for Translational Medicine, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA 19107, USA; (S.S.); (A.L.S.)
| | - Mudit Tyagi
- Center for Translational Medicine, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA 19107, USA; (S.S.); (A.L.S.)
- Correspondence: ; Tel.: +1-215-503-5157 or +1-703-909-9420
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6
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Shen S, Zhang C, Xu YM, Shi CH. The Role of Pathogens and Anti-Infective Agents in Parkinson's Disease, from Etiology to Therapeutic Implications. JOURNAL OF PARKINSONS DISEASE 2021; 12:27-44. [PMID: 34719435 PMCID: PMC8842782 DOI: 10.3233/jpd-212929] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Parkinson's disease is a debilitating neurodegenerative disorder whose etiology is still unclear, hampering the development of effective treatments. There is an urgent need to identify the etiology and provide further effective treatments. Recently, accumulating evidence has indicated that infection may play a role in the etiology of Parkinson's disease. The infective pathogens may act as a trigger for Parkinson's disease, the most common of which are hepatitis C virus, influenza virus, and Helicobacter pylori. In addition, gut microbiota is increasingly recognized to influence brain function through the gut-brain axis, showing an important role in the pathogenesis of Parkinson's disease. Furthermore, a series of anti-infective agents exhibit surprising neuroprotective effects via various mechanisms, such as interfering with α-synuclein aggregation, inhibiting neuroinflammation, attenuating oxidative stress, and preventing from cell death, independent of their antimicrobial effects. The pleiotropic agents affect important events in the pathogenesis of Parkinson's disease. Moreover, most of them are less toxic, clinically safe and have good blood-brain penetrability, making them hopeful candidates for the treatment of Parkinson's disease. However, the use of antibiotics and subsequent gut dysbiosis may also play a role in Parkinson's disease, making the long-term effects of anti-infective drugs worthy of further consideration and exploration. This review summarizes the current evidence for the association between infective pathogens and Parkinson's disease and subsequently explores the application prospects of anti-infective drugs in Parkinson's disease treatment, providing novel insights into the pathogenesis and treatment of Parkinson's disease.
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Affiliation(s)
- Si Shen
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China
| | - Chan Zhang
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China
| | - Yu-Ming Xu
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Institute of Neuroscience, Zhengzhou University, Zhengzhou, Henan, China
| | - Chang-He Shi
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Institute of Neuroscience, Zhengzhou University, Zhengzhou, Henan, China
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7
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HIV-Associated Neurotoxicity: The Interplay of Host and Viral Proteins. Mediators Inflamm 2021; 2021:1267041. [PMID: 34483726 PMCID: PMC8410439 DOI: 10.1155/2021/1267041] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 07/12/2021] [Accepted: 08/09/2021] [Indexed: 11/18/2022] Open
Abstract
HIV-1 can incite activation of chemokine receptors, inflammatory mediators, and glutamate receptor-mediated excitotoxicity. The mechanisms associated with such immune activation can disrupt neuronal and glial functions. HIV-associated neurocognitive disorder (HAND) is being observed since the beginning of the AIDS epidemic due to a change in the functional integrity of cells from the central nervous system (CNS). Even with the presence of antiretroviral therapy, there is a decline in the functioning of the brain especially movement skills, noticeable swings in mood, and routine performance activities. Under the umbrella of HAND, various symptomatic and asymptomatic conditions are categorized and are on a rise despite the use of newer antiretroviral agents. Due to the use of long-lasting antiretroviral agents, this deadly disease is becoming a manageable chronic condition with the occurrence of asymptomatic neurocognitive impairment (ANI), symptomatic mild neurocognitive disorder, or HIV-associated dementia. In-depth research in the pathogenesis of HIV has focused on various mechanisms involved in neuronal dysfunction and associated toxicities ultimately showcasing the involvement of various pathways. Increasing evidence-based studies have emphasized a need to focus and explore the specific pathways in inflammation-associated neurodegenerative disorders. In the current review, we have highlighted the association of various HIV proteins and neuronal cells with their involvement in various pathways responsible for the development of neurotoxicity.
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Saloner R, Cherner M, Sundermann EE, Watson CWM, Iudicello JE, Letendre SL, Kumar A, Ellis RJ. COMT val158met genotype alters the effects of methamphetamine dependence on dopamine and dopamine-related executive function: preliminary findings. Psychiatry Res 2020; 292:113269. [PMID: 32739643 PMCID: PMC7530039 DOI: 10.1016/j.psychres.2020.113269] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Revised: 06/24/2020] [Accepted: 06/30/2020] [Indexed: 11/19/2022]
Abstract
The Met-allele of the COMT Val158Met polymorphism slows metabolism and increases bioavailability of dopamine (DA) in the prefrontal cortex compared to the Val-allele. Healthy Met-carriers outperform Val-carriers on executive function (EF) tests, yet this 'advantage' disappears in methamphetamine (METH) dependence. Met-carriers may be disproportionately vulnerable to METH-related perturbations of DA, yet it is unknown whether COMT modulates METH effects on CSF DA biomarkers. Participants were 75 METH+ and 47 METH- men who underwent neurocognitive testing, COMT genotyping, and lumbar puncture. CSF was assayed for DA and its metabolite, homovanillic acid (HVA). Separate linear models regressed DA, HVA, and HVA/DA ratios on COMT, METH and their interaction. Pearson correlations examined associations between DA and EF. Significant interactions indicated that METH+ had lower DA and higher HVA/DA ratios among Met/Met, but not Val/Met-or Val/Val. Met/Met-exhibited the highest DA levels among METH-, whereas DA levels were comparable between Met/Met-and Val-carriers among METH+. Higher DA correlated with better EF in METH- Met/Met, but did not predict EF in the entire sample. DA was expectedly higher in METH- Met/Met, yet a discordant genotype-phenotype profile emerged in METH+ Met/Met, consistent with the notion that slow DA clearance exacerbates METH-associated DA dysregulation.
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Affiliation(s)
- Rowan Saloner
- San Diego State University/University of California, San Diego Joint Doctoral Program in Clinical Psychology, San Diego, CA, USA; Department of Psychiatry, University of California, San Diego, HIV Neurobehavioral Research Program, San Diego, CA, USA.
| | - Mariana Cherner
- Department of Psychiatry, University of California, San Diego, HIV Neurobehavioral Research Program, San Diego, CA, USA
| | - Erin E Sundermann
- Department of Psychiatry, University of California, San Diego, HIV Neurobehavioral Research Program, San Diego, CA, USA
| | - Caitlin Wei-Ming Watson
- San Diego State University/University of California, San Diego Joint Doctoral Program in Clinical Psychology, San Diego, CA, USA; Department of Psychiatry, University of California, San Diego, HIV Neurobehavioral Research Program, San Diego, CA, USA
| | - Jennifer E Iudicello
- Department of Psychiatry, University of California, San Diego, HIV Neurobehavioral Research Program, San Diego, CA, USA
| | - Scott L Letendre
- Department of Psychiatry, University of California, San Diego, HIV Neurobehavioral Research Program, San Diego, CA, USA
| | - Adarsh Kumar
- Department of Psychiatry and Behavioral Sciences, University of Miami, Miami, FL, USA
| | - Ronald J Ellis
- Department of Psychiatry, University of California, San Diego, HIV Neurobehavioral Research Program, San Diego, CA, USA; Department of Neurosciences, University of California, San Diego, San Diego, CA, USA
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Dopaminergic impact of cART and anti-depressants on HIV neuropathogenesis in older adults. Brain Res 2019; 1723:146398. [PMID: 31442412 DOI: 10.1016/j.brainres.2019.146398] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Revised: 08/09/2019] [Accepted: 08/19/2019] [Indexed: 01/21/2023]
Abstract
The success of combination antiretroviral therapy (cART) has transformed HIV infection into a chronic condition, resulting in an increase in the number of older, cART-treated adults living with HIV. This has increased the incidence of age-related, non-AIDS comorbidities in this population. One of the most common comorbidities is depression, which is also associated with cognitive impairment and a number of neuropathologies. In older people living with HIV, treating these overlapping disorders is complex, often creating pill burden or adverse drug-drug interactions that can exacerbate these neurologic disorders. Depression, NeuroHIV and many of the neuropsychiatric therapeutics used to treat them impact the dopaminergic system, suggesting that dopaminergic dysfunction may be a common factor in the development of these disorders. Further, changes in dopamine can influence the development of inflammation and the regulation of immune function, which are also implicated in the progression of NeuroHIV and depression. Little is known about the optimal clinical management of drug-drug interactions between cART drugs and antidepressants, particularly in regard to dopamine in older people living with HIV. This review will discuss those interactions, first examining the etiology of NeuroHIV and depression in older adults, then discussing the interrelated effects of dopamine and inflammation on these disorders, and finally reviewing the activity and interactions of cART drugs and antidepressants on each of these factors. Developing better strategies to manage these comorbidities is critical to the health of the aging, HIV-infected population, as the older population may be particularly vulnerable to drug-drug interactions affecting dopamine.
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10
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Fields JA, Ellis RJ. HIV in the cART era and the mitochondrial: immune interface in the CNS. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2019; 145:29-65. [PMID: 31208526 DOI: 10.1016/bs.irn.2019.04.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
HIV-associated neurocognitive disorders (HAND) persist in the era of effective combined antiretroviral therapy (cART). A large body of literature suggests that mitochondrial dysfunction is a prospective etiology of HAND in the cART era. While viral load is often suppressed and the immune system remains intact in HIV+ patients on cART, evidence suggests that the central nervous system (CNS) acts as a reservoir for virus and low-level expression of viral proteins, which interact with mitochondria. In particular, the HIV proteins glycoprotein 120, transactivator of transcription, viral protein R, and negative factor have each been linked to mitochondrial dysfunction in the brain. Moreover, cART drugs have also been shown to have detrimental effects on mitochondrial function. Here, we review the evidence generated from human studies, animal models, and in vitro models that support a role for HIV proteins and/or cART drugs in altered production of adenosine triphosphate, mitochondrial dynamics, mitophagy, calcium signaling and apoptosis, oxidative stress, mitochondrial biogenesis, and immunometabolism in the CNS. When insightful, evidence of HIV or cART-induced mitochondrial dysfunction in the peripheral nervous system or other cell types is discussed. Lastly, therapeutic approaches to targeting mitochondrial dysfunction have been summarized with the aim of guiding new investigations and providing hope that mitochondrial-based drugs may provide relief for those suffering with HAND.
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Affiliation(s)
- Jerel Adam Fields
- Department of Psychiatry, University of California San Diego, La Jolla, CA, United States.
| | - Ronald J Ellis
- Department of Neuroscience, University of California San Diego, La Jolla, CA, United States
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11
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Roda RH, Hoke A. Mitochondrial dysfunction in HIV-induced peripheral neuropathy. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2019; 145:67-82. [PMID: 31208527 DOI: 10.1016/bs.irn.2019.04.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Mitochondria play an essential role in cellular energy production and calcium homeostasis. Abnormalities in mitochondrial homeostasis and function are seen in several acquired as well as genetic neuropathies, emphasizing their prominent role in neuronal cell activities. Chronic infection with HIV, even when appropriately treated, is a risk factor for developing peripheral neuropathy. In this chapter, we discuss the way in which HIV infection, the resultant toxic viral products that are generated, and some of the viral inhibitors used in its treatment may lead to abnormal mitochondrial function. Of importance are the effects on mitochondrial DNA replication and the neurotoxic effects of the viral gp120 protein. One aspect of mitochondrial dysfunction that remains unexplored is the role of the interaction between mitochondria and the endoplasmic reticulum as a possible target of disruption in HIV neuropathy.
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Affiliation(s)
- Ricardo H Roda
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States.
| | - Ahmet Hoke
- Solomon H. Snyder Department of Neuroscience and Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
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12
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Abstract
Endothelins were discovered more than thirty years ago as potent vasoactive compounds. Beyond their well-documented cardiovascular properties, however, the contributions of the endothelin pathway have been demonstrated in several neuroinflammatory processes and the peptides have been reported as clinically relevant biomarkers in neurodegenerative diseases. Several studies report that endothelin-1 significantly contributes to the progression of neuroinflammatory processes, particularly during infections in the central nervous system (CNS), and is associated with a loss of endothelial integrity at the blood brain barrier level. Because of the paucity of clinical trials with endothelin-1 antagonists in several infectious and non-infectious neuroinflammatory diseases, it remains an open question whether the 21 amino acid peptide is a mediator/modulator rather than a biomarker of the progression of neurodegeneration. This review focuses on the potential roles of endothelins in the pathology of neuroinflammatory processes, including infectious diseases of viral, bacterial or parasitic origin in which the synthesis of endothelins or its pharmacology have been investigated from the cell to the bedside in several cases, as well as in non-infectious inflammatory processes such as neurodegenerative disorders like Alzheimers Disease or central nervous system vasculitis.
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13
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The role of catecholamines in HIV neuropathogenesis. Brain Res 2018; 1702:54-73. [PMID: 29705605 DOI: 10.1016/j.brainres.2018.04.030] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 04/21/2018] [Accepted: 04/24/2018] [Indexed: 12/21/2022]
Abstract
The success of anti-retroviral therapy has improved the quality of life and lifespan of HIV + individuals, transforming HIV infection into a chronic condition. These improvements have come with a cost, as chronic HIV infection and long-term therapy have resulted in the emergence of a number of new pathologies. This includes a variety of the neuropathological and neurocognitive effects collectively known as HIVassociated neurocognitive disorders (HAND) or NeuroHIV. These effects persist even in the absence of viral replication, suggesting that they are mediated the long-term changes in the CNS induced by HIV infection rather than by active replication. Among these effects are significant changes in catecholaminergic neurotransmission, especially in dopaminergic brain regions. In HIV-infected individuals not treated with ARV show prominent neuropathology is common in dopamine-rich brain regions and altered autonomic nervous system activity. Even infected individuals on therapy, there is significant dopaminergic neuropathology, and elevated stress and norepinephrine levels correlate with a decreased effectiveness of antiretroviral drugs. As catecholamines function as immunomodulatory factors, the resultant dysregulation of catecholaminergic tone could substantially alter the development of HIVassociated neuroinflammation and neuropathology. In this review, we discuss the role of catecholamines in the etiology of HIV neuropathogenesis. Providing a comprehensive examination of what is known about these molecules in the context of HIV-associated disease demonstrates the importance of further studies in this area, and may open the door to new therapeutic strategies that specifically ameliorate the effects of catecholaminergic dysregulation on NeuroHIV.
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Rozzi SJ, Avdoshina V, Fields JA, Trejo M, Ton HT, Ahern GP, Mocchetti I. Human Immunodeficiency Virus Promotes Mitochondrial Toxicity. Neurotox Res 2017; 32:723-733. [PMID: 28695547 DOI: 10.1007/s12640-017-9776-z] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 06/15/2017] [Accepted: 06/28/2017] [Indexed: 01/09/2023]
Abstract
Combined antiretroviral therapies (cART) have had remarkable success in reducing morbidity and mortality among patients infected with human immunodeficiency virus (HIV). However, mild forms of HIV-associated neurocognitive disorders (HAND), characterized by loss of synapses, remain. cART may maintain an undetectable HIV RNA load but does not eliminate the expression of viral proteins such as trans-activator of transcription (Tat) and the envelope glycoprotein gp120 in the brain. These two viral proteins are known to promote synaptic simplifications by several mechanisms, including alteration of mitochondrial function and dynamics. In this review, we aim to outline the many targets and pathways used by viral proteins to alter mitochondria dynamics, which contribute to HIV-induced neurotoxicity. A better understanding of these pathways is crucial for the development of adjunct therapies for HAND.
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Affiliation(s)
- Summer J Rozzi
- Laboratory of Preclinical Neurobiology, Department of Neuroscience, Georgetown University Medical Center, 3970 Reservoir Rd NW, Washington, DC, 20057, USA
| | - Valeria Avdoshina
- Laboratory of Preclinical Neurobiology, Department of Neuroscience, Georgetown University Medical Center, 3970 Reservoir Rd NW, Washington, DC, 20057, USA
| | - Jerel A Fields
- Department of Psychiatry, University of California San Diego, La Jolla, CA, USA
| | - Margarita Trejo
- Department of Psychiatry, University of California San Diego, La Jolla, CA, USA
| | - Hoai T Ton
- Department of Pharmacology, Georgetown University Medical Center, Washington, DC, 20057, USA
| | - Gerard P Ahern
- Department of Pharmacology, Georgetown University Medical Center, Washington, DC, 20057, USA
| | - Italo Mocchetti
- Laboratory of Preclinical Neurobiology, Department of Neuroscience, Georgetown University Medical Center, 3970 Reservoir Rd NW, Washington, DC, 20057, USA.
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15
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Liu B, Liu X, Tang SJ. Interactions of Opioids and HIV Infection in the Pathogenesis of Chronic Pain. Front Microbiol 2016; 7:103. [PMID: 26903982 PMCID: PMC4748029 DOI: 10.3389/fmicb.2016.00103] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 01/19/2016] [Indexed: 12/30/2022] Open
Abstract
Over 50% of HIV-1/AIDS patients suffer chronic pain. Currently, opioids are the cornerstone medications for treating severe pain in these patients. Ironically, emerging clinical data indicates that repeated use of opiate pain medicines might in fact heighten the chronic pain states in HIV patients. Both laboratory-based and clinical studies strongly suggest that opioids exacerbate the detrimental effects of HIV-1 infection on the nervous system, both on neurons and glia. The combination of opioids and HIV-1infection may promote the damage of neurons, including those in the pain sensory and transmission pathway, by activating both caspase-dependent and caspase-independent pro-apoptotic pathways. In addition, the opiate-HIV-1 interaction may also cause widespread disturbance of glial function and elicit glial-derived pro-inflammatory responses that dysregulate neuronal function. The deregulation of neuron-glia cross-talk that occurs with the combination of HIV-1 and opioids appears to play an important role in the development of the pathological pain state. In this article, we wish to provide an overview of the potential molecular and cellular mechanisms by which opioids may interact with HIV-1 to cause neurological problems, especially in the context of HIV-associated pathological pain. Elucidating the underlying mechanisms will help researchers and clinicians to understand how chronic use of opioids for analgesia enhances HIV-associated pain. It will also assist in optimizing therapeutic approaches to prevent or minimize this significant side effect of opiate analgesics in pain management for HIV patients.
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Affiliation(s)
- Bolong Liu
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, GalvestonTX, USA; Department of Urology, Third Affiliated Hospital of Sun Yat-Sen UniversityGuangzhou, China
| | - Xin Liu
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston TX, USA
| | - Shao-Jun Tang
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston TX, USA
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16
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Fitting S, Booze RM, Mactutus CF. HIV-1 proteins, Tat and gp120, target the developing dopamine system. Curr HIV Res 2015; 13:21-42. [PMID: 25613135 DOI: 10.2174/1570162x13666150121110731] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2014] [Revised: 11/17/2014] [Accepted: 12/23/2014] [Indexed: 11/22/2022]
Abstract
In 2014, 3.2 million children (< 15 years of age) were estimated to be living with HIV and AIDS worldwide, with the 240,000 newly infected children in the past year, i.e., another child infected approximately every two minutes [1]. The primary mode of HIV infection is through mother-to-child transmission (MTCT), occurring either in utero, intrapartum, or during breastfeeding. The effects of HIV-1 on the central nervous system (CNS) are putatively accepted to be mediated, in part, via viral proteins, such as Tat and gp120. The current review focuses on the targets of HIV-1 proteins during the development of the dopamine (DA) system, which appears to be specifically susceptible in HIV-1-infected children. Collectively, the data suggest that the DA system is a clinically relevant target in chronic HIV-1 infection, is one of the major targets in pediatric HIV-1 CNS infection, and may be specifically susceptible during development. The present review discusses the development of the DA system, follows the possible targets of the HIV-1 proteins during the development of the DA system, and suggests potential therapeutic approaches. By coupling our growing understanding of the development of the CNS with the pronounced age-related differences in disease progression, new light may be shed on the neurological and neurocognitive deficits that follow HIV-1 infection.
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Affiliation(s)
| | - Rosemarie M Booze
- Department of Psychology, 1512 Pendleton Street, University of South Carolina, Columbia, SC 29208, USA.
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17
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Neuropathological sequelae of Human Immunodeficiency Virus and apathy: A review of neuropsychological and neuroimaging studies. Neurosci Biobehav Rev 2015; 55:147-64. [PMID: 25944459 DOI: 10.1016/j.neubiorev.2015.04.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Revised: 04/22/2015] [Accepted: 04/23/2015] [Indexed: 02/07/2023]
Abstract
Apathy remains a common neuropsychiatric disturbance in the Human Immunodeficiency Virus (HIV-1) despite advances in anti-retroviral treatment (ART). The goal of the current review is to recapitulate findings relating apathy to the deleterious biobehavioral effects of HIV-1 in the post-ART era. Available literatures demonstrate that the emergence of apathy with other neurocognitive and neuropsychiatric symptoms may be attributed to neurotoxic effects of viral proliferation, e.g., aggregative effect of Tat and gp120 on apoptosis, transport and other enzymatic reactions amongst dopaminergic neurons and neuroglia. An assortment of neuroimaging modalities converge on the severity of apathy symptoms associated with the propensity of the virus to replicate within frontal-striatal brain circuits that facilitate emotional processing. Burgeoning research into functional brain connectivity also supports the effects of microvascular and neuro-inflammatory injury linked to aging with HIV-1 on the presentation of neuropsychiatric symptoms. Summarizing these findings, we review domains of HIV-associated neurocognitive and neuropsychiatric impairment linked to apathy in HIV. Taken together, these lines of research suggest that loss of affective, cognitive and behavioral inertia is commensurate with the neuropathology of HIV-1.
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18
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McIntosh S, Sexton T, Pattison LP, Childers SR, Hemby SE. Increased Sensitivity to Cocaine Self-Administration in HIV-1 Transgenic Rats is Associated with Changes in Striatal Dopamine Transporter Binding. J Neuroimmune Pharmacol 2015; 10:493-505. [PMID: 25749646 DOI: 10.1007/s11481-015-9594-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 02/13/2015] [Indexed: 12/14/2022]
Abstract
Cocaine abuse in HIV patients accelerates the progression and severity of neuropathology, motor impairment and cognitive dysfunction compared to non-drug using HIV patients. Cocaine and HIV interact with the dopamine transporter (DAT); however, the effect of their interaction on DAT binding remains understudied. The present study compared the dose-response functions for intravenous self-administration of cocaine and heroin between male HIV-1 transgenic (HIV-1 Tg) and Fischer 344 rats. The cocaine and heroin dose-response functions exhibit an inverted U-shape for both HIV-1 Tg and F344 rats. For cocaine, the number of infusions for each dose on the ascending limb was greater for HIV-1 Tg versus F344 rats. No significant changes in the heroin dose-response function were observed in HIV-1 Tg animals. Following the conclusion of self-administration experiments, DAT binding was assessed in striatal membranes. Saturation binding of the cocaine analog [(125)I] 3β-(4-iodophenyl)tropan-2β-carboxylic acid methyl ester ([(125)I]RTI-55) in rat striatal membranes resulted in binding curves that were best fit to a two-site binding model, allowing for calculation of dissociation constant (Kd) and binding density (Bmax) values that correspond to high- and low-affinity DAT binding sites. Control HIV-1 Tg rats exhibited a significantly greater affinity (i.e., decrease in Kd value) in the low-affinity DAT binding site compared to control F344 rats. Furthermore, cocaine self-administration in HIV-1 Tg rats increased low-affinity Kd (i.e., decreased affinity) compared to levels observed in control F344 rats. Cocaine also increased low-affinity Bmax in HIV-1 Tg rats as compared to controls, indicating an increase in the number of low-affinity DAT binding sites. F344 rats did not exhibit any change in high- or low-affinity Kd or Bmax values following cocaine or heroin self-administration. The increase in DAT affinity in cocaine HIV-1 Tg rats is consistent with the leftward shift of the ascending limb of the cocaine dose-response curve observed in HIV-1 Tg vs. F344 rats, and has major implications for the function of cocaine binding to DAT in HIV patients. The absence of HIV-related changes in heroin intake are likely due to less dopaminergic involvement in the mediation of heroin reward, further emphasizing the preferential influence of HIV on dopamine-related behaviors.
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Affiliation(s)
- Scot McIntosh
- Department of Physiology and Pharmacology, Center for the Neurobiology of Addiction Treatment, Winston-Salem, NC, USA
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19
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Sundermann EE, Bishop JR, Rubin LH, Little DM, Meyer VJ, Martin E, Weber K, Cohen M, Maki PM. Genetic predictor of working memory and prefrontal function in women with HIV. J Neurovirol 2015; 21:81-91. [PMID: 25515329 PMCID: PMC4319991 DOI: 10.1007/s13365-014-0305-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 10/07/2014] [Accepted: 11/20/2014] [Indexed: 10/24/2022]
Abstract
The Val158Met (rs4680) single-nucleotide polymorphism (SNP) of the catechol-O-methyltransferase gene (COMT) influences executive function and prefrontal function through its effect on dopamine (DA) metabolism. Both HIV and the Val allele of the Val158Met SNP are associated with compromised executive function and inefficient prefrontal function. The present study used behavioral and neuroimaging techniques to determine independent and interactive associations between HIV serostatus and COMT genotype on working memory and prefrontal function in women. For the behavioral study, 54 HIV-infected and 33 HIV-uninfected women completed the 0-, 1-, and 2-back conditions of the verbal N-back, a working memory test. For the imaging study, 36 women (23 HIV-infected, 13 HIV-uninfected) underwent functional magnetic resonance imaging (fMRI) assessments while completing the N-back task. HIV-infected women demonstrated significantly worse N-back performance compared with HIV-uninfected women (p < 0.05). A significant serostatus by genotype interaction (p < 0.01) revealed that, among Val/Val, but not Met allele carriers, HIV-infected women performed significantly worse than HIV-uninfected controls across N-back conditions (p < 0.01). Analogous to behavioral findings, a serostatus by genotype interaction revealed that HIV-infected Val/Val carriers showed significantly greater prefrontal activation compared with HIV-uninfected Val/Val carriers (p < 0.01). Conversely, HIV-uninfected Met allele carriers demonstrated significantly greater prefrontal activation compared with HIV-infected Met allele carriers. Findings suggest that the combination of HIV infection and the Val/Val COMT genotype leads to working memory deficits and altered prefrontal function in HIV-infected individuals.
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Affiliation(s)
- Erin E Sundermann
- Department of Neurology, Albert Einstein College of Medicine, 1165 Morris Park Ave., New York, NY, 10461, USA,
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20
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The gp120 protein is a second determinant of decreased neurovirulence of Indian HIV-1C isolates compared to southern African HIV-1C isolates. PLoS One 2014; 9:e107074. [PMID: 25188269 PMCID: PMC4154767 DOI: 10.1371/journal.pone.0107074] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Accepted: 08/12/2014] [Indexed: 11/19/2022] Open
Abstract
Regional differences in neurovirulence have been documented among subtype/clade-C HIV-1 isolates in India and Southern Africa. We previously demonstrated that a C31S substitution in Clade-C Tat dicysteine motif reduces monocyte recruitment, cytokine induction and direct neurotoxicity. Therefore, this polymorphism is considered to be a causative factor for these differences in neurovirulence. We previously reported on the genotypic differences in Tat protein between clade-C and rest of the clades showing that approximately 90% of clade-C HIV-1 Tat sequences worldwide contained this C31S polymorphism, while 99% of non-clade C isolates lacked this Tat polymorphism at C31 residue (Ranga et al. (2004) J Virol 78∶2586–2590). Subsequently, we documented intra-clade-C differences in the frequency of Tat dicysteine variants between India and Southern Africa, as the basis for differential disease severity and showed the importance of the Tat dicysteine motif for neuropathogenesis using small animal models. We have now examined if determinants of neurovirulence besides Tat are different between the clade-C HIV-1 isolates from Southern Africa and India. Envelope glycoprotein gp120 is a well-documented contributor to neurotoxicity. We found that gp120 sequences of HIV-1 isolates from these two regions are genetically distinct. In order to delineate the contribution of gp120 to neurovirulence, we compared direct in vitro neurotoxicity of HIV-infected supernatants of a representative neurovirulent US clade-B isolate with two isolates each from Southern Africa and India using primary human neurons and SH-SY5Y neuroblastoma cells. Immunodepletion of gp120 of both US clade B and the Southern African clade C isolates revealed robust decreases in neurotoxicity, while that of the Indian isolates showed minimal effect on neurotoxicity. The gp120 as a cause of differential neurotoxicity was further confirmed using purified recombinant gp120 from HIV isolates from these regions. We conclude that gp120 is one of the key factors responsible for the decreased neurovirulence of Indian clade C HIV-1 isolates when compared to South African clade C HIV-1.
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21
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Abstract
The implementation of new antiretroviral therapies targeting transcription of early viral proteins in postintegrated HIV-1 can aid in overcoming current therapy limitations. Using high-throughput screening assays, we have previously described a novel Tat-dependent HIV-1 transcriptional inhibitor named 6-bromoindirubin-3'-oxime (6BIO). The screening of 6BIO derivatives yielded unique compounds that show potent inhibition of HIV-1 transcription. We have identified a second-generation derivative called 18BIOder as an inhibitor of HIV-1 Tat-dependent transcription in TZM-bl cells and a potent inhibitor of GSK-3β kinase in vitro. Structurally, 18BIOder is half the molecular weight and structure of its parental compound, 6BIO. More importantly, we also have found a different GSK-3β complex present only in HIV-1-infected cells. 18BIOder preferentially inhibits this novel kinase complex from infected cells at nanomolar concentrations. Finally, we observed that neuronal cultures treated with Tat protein are protected from Tat-mediated cytotoxicity when treated with 18BIOder. Overall, our data suggest that HIV-1 Tat-dependent transcription is sensitive to small-molecule inhibition of GSK-3β.
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22
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Hu S, Sheng WS, Rock RB. CB2 receptor agonists protect human dopaminergic neurons against damage from HIV-1 gp120. PLoS One 2013; 8:e77577. [PMID: 24147028 PMCID: PMC3798286 DOI: 10.1371/journal.pone.0077577] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Accepted: 09/03/2013] [Indexed: 11/18/2022] Open
Abstract
Despite the therapeutic impact of anti-retroviral therapy, HIV-1-associated neurocognitive disorder (HAND) remains a serious threat to AIDS patients, and there currently remains no specific therapy for the neurological manifestations of HIV-1. Recent work suggests that the nigrostriatal dopaminergic area is a critical brain region for the neuronal dysfunction and death seen in HAND and that human dopaminergic neurons have a particular sensitivity to gp120-induced damage, manifested as reduced function (decreased dopamine uptake), morphological changes, and reduced viability. Synthetic cannabinoids inhibit HIV-1 expression in human microglia, suppress production of inflammatory mediators in human astrocytes, and there is substantial literature demonstrating the neuroprotective properties of cannabinoids in other neuropathogenic processes. Based on these data, experiments were designed to test the hypothesis that synthetic cannabinoids will protect dopaminergic neurons against the toxic effects of the HIV-1 protein gp120. Using a human mesencephalic neuronal/glial culture model, which contains dopaminergic neurons, microglia, and astrocytes, we were able to show that the CB1/CB2 agonist WIN55,212-2 blunts gp120-induced neuronal damage as measured by dopamine transporter function, apoptosis and lipid peroxidation; these actions were mediated principally by the CB2 receptor. Adding supplementary human microglia to our cultures enhances gp120-induced damage; WIN55,212-2 is able to alleviate this enhanced damage. Additionally, WIN55,212-2 inhibits gp120-induced superoxide production by purified human microglial cells, inhibits migration of human microglia towards supernatants generated from gp120-stimulated human mesencephalic neuronal/glial cultures and reduces chemokine and cytokine production from the human mesencephalic neuronal/glial cultures. These data suggest that synthetic cannabinoids are capable of protecting human dopaminergic neurons from gp120 in a variety of ways, acting principally through the CB2 receptors and microglia.
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Affiliation(s)
- Shuxian Hu
- Center for Infectious Diseases and Microbiology Translational Research, Division of Infectious Diseases and International Medicine, Department of Medicine, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
| | - Wen S. Sheng
- Center for Infectious Diseases and Microbiology Translational Research, Division of Infectious Diseases and International Medicine, Department of Medicine, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
| | - R. Bryan Rock
- Center for Infectious Diseases and Microbiology Translational Research, Division of Infectious Diseases and International Medicine, Department of Medicine, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America
- * E-mail:
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23
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Del Guerra FB, Fonseca JLI, Figueiredo VM, Ziff EB, Konkiewitz EC. Human immunodeficiency virus-associated depression: contributions of immuno-inflammatory, monoaminergic, neurodegenerative, and neurotrophic pathways. J Neurovirol 2013; 19:314-27. [PMID: 23868513 DOI: 10.1007/s13365-013-0177-7] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 05/24/2013] [Accepted: 06/05/2013] [Indexed: 12/14/2022]
Abstract
In the era of greatly improved pharmacological treatment of HIV infection through highly active antiretroviral therapy (HAART), HIV patients experience reduced viral loads, reduced opportunistic infections, increased CD4+ T cell count, and greater life expectancy. Although life expectancy is increased, patients often develop neurological disturbances that may persist for long periods, seriously jeopardizing quality of life and adherence to the medication protocols of HAART. For these reasons, HIV-associated neurological disorders have gained importance in both clinical and basic investigations of HIV infection. Depression is the most prevalent neuropsychiatric disorder among people living with HIV. In this review, we discuss how HIV can predispose infected individuals to depression by several interrelated mechanisms. These include inducing chronic elevation of cytokines through activation of microglia and astrocytes; decreasing monoaminergic function; inducing neurotoxicity, especially in dopaminergic neurons; and reducing brain-derived neurotrophic factor. These viral pathways interact with psychosocial factors to create the depressive state. HIV depression has a great impact on quality of life and implementation of antiretroviral therapy, and thus, recognition of these modes of action is significant for understanding HIV neuropathology and for selecting modalities for pharmacologic treatment.
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Affiliation(s)
- F B Del Guerra
- Faculdade de Ciências da Saude, Universidade Federal da Grande Dourados Unidade II, Rodovia MS 162, Mato Grosso do Sul, Brazil
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24
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Abstract
Human immunodeficiency virus type 1 is associated with the development of neurocognitive disorders in many infected individuals, including a broad spectrum of motor impairments and cognitive deficits. Despite extensive research, the pathogenesis of HIV-associated neurocognitive disorders (HAND) is still not clear. This review provides a comprehensive view of HAND, including HIV neuroinvasion, HAND diagnosis and different level of disturbances, influence of highly-active antiretroviral therapy to HIV-associated dementia (HAD), possible pathogenesis of HAD, etc. Together, this review will give a thorough and clear understanding of HAND, especially HAD, which will be vital for future research, diagnosis and treatment.
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Affiliation(s)
- Li Zhou
- Retroviral Genetics Division, Center for Virus Research, Westmead Millennium Institute, Westmead Hospital, The University of Sydney , Australia
| | - Nitin K Saksena
- Retroviral Genetics Division, Center for Virus Research, Westmead Millennium Institute, Westmead Hospital, The University of Sydney , Australia
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25
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Henry BL, Geyer MA, Buell M, Perry W, Young JW, Minassian A. Behavioral effects of chronic methamphetamine treatment in HIV-1 gp120 transgenic mice. Behav Brain Res 2012; 236:210-220. [PMID: 22960458 DOI: 10.1016/j.bbr.2012.08.037] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Revised: 08/20/2012] [Accepted: 08/23/2012] [Indexed: 02/05/2023]
Abstract
Methamphetamine (METH) dependence is frequently comorbid with HIV infection. Both factors are independently characterized by inhibitory deficits, which may manifest as increased motor activity, inappropriate perseverative behavior, and elevated exploratory responses to novel stimuli, but the effect of combined METH exposure and HIV is not well understood. In this study, we administered a chronic escalation/binge regimen of METH or vehicle treatment to wildtype (WT) or transgenic (tg) mice expressing the HIV-1 gp120 envelope protein and quantified disinhibition during the 7 days following drug withdrawal. We hypothesized that gp120tg mice administered chronic METH would exhibit more pronounced inhibitory deficits compared to vehicle-treated WT or gp120tg animals. Our results showed that METH treatment alone increased novel object interaction while female METH-treated gp120tg mice exhibited the highest level of exploration (holepoking) compared to other female mice. Transgenic mice exhibited fewer rears relative to WT, slightly less locomotion, and also demonstrated a trend toward more perseverative motor patterns. In summary, both METH treatment and gp120 expression may modify inhibition, but such effects are selective and dependent upon variations in age and sex that could impact dopamine and frontostriatal function. These findings illustrate the need to improve our knowledge about the combined effects of HIV and substance use and facilitate improved treatment methods for comorbid disease and drug dependence.
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Affiliation(s)
- Brook L Henry
- University of California San Diego, Department of Psychiatry, La Jolla, CA, United States
| | - Mark A Geyer
- University of California San Diego, Department of Psychiatry, La Jolla, CA, United States; VA San Diego Healthcare System, San Diego, CA, United States
| | - Mahalah Buell
- University of California San Diego, Department of Psychiatry, La Jolla, CA, United States
| | - William Perry
- University of California San Diego, Department of Psychiatry, La Jolla, CA, United States
| | - Jared W Young
- University of California San Diego, Department of Psychiatry, La Jolla, CA, United States
| | - Arpi Minassian
- University of California San Diego, Department of Psychiatry, La Jolla, CA, United States; Center for Excellence in Substance Abuse and Mental Health (CESAMH), Veteran's Administration, San Diego, CA, United States.
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26
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Hauser KF, Fitting S, Dever SM, Podhaizer EM, Knapp PE. Opiate drug use and the pathophysiology of neuroAIDS. Curr HIV Res 2012; 10:435-52. [PMID: 22591368 PMCID: PMC3431547 DOI: 10.2174/157016212802138779] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Revised: 01/12/2012] [Accepted: 01/14/2012] [Indexed: 11/22/2022]
Abstract
Opiate abuse and HIV-1 have been described as interrelated epidemics, and even in the advent of combined anti-retroviral therapy, the additional abuse of opiates appears to result in greater neurologic and cognitive deficits. The central nervous system (CNS) is particularly vulnerable to interactive opiate-HIV-1 effects, in part because of the unique responses of microglia and astroglia. Although neurons are principally responsible for behavior and cognition, HIV-1 infection and replication in the brain is largely limited to microglia, while astroglia and perhaps glial progenitors can be latently infected. Thus, neuronal dysfunction and injury result from cellular and viral toxins originating from HIV-1 infected/exposed glia. Importantly, subsets of glial cells including oligodendrocytes, as well as neurons, express µ-opioid receptors and therefore can be direct targets for heroin and morphine (the major metabolite of heroin in the CNS), which preferentially activate µ-opioid receptors. This review highlights findings that neuroAIDS is a glially driven disease, and that opiate abuse may act at multiple glial-cell types to further compromise neuron function and survival. The ongoing, reactive cross-talk between opiate drug and HIV-1 co-exposed microglia and astroglia appears to exacerbate critical proinflammatory and excitotoxic events leading to neuron dysfunction, injury, and potentially death. Opiates enhance synaptodendritic damage and a loss of synaptic connectivity, which is viewed as the substrate of cognitive deficits. We especially emphasize that opioid signaling and interactions with HIV-1 are contextual, differing among cell types, and even within subsets of the same cell type. For example, astroglia even within a single brain region are heterogeneous in their expression of µ-, δ-, and κ-opioid receptors, as well as CXCR4 and CCR5, and Toll-like receptors. Thus, defining the distinct targets engaged by opiates in each cell type, and among brain regions, is critical to an understanding of how opiate abuse exacerbates neuroAIDS.
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Affiliation(s)
- Kurt F Hauser
- Department of Pharmacology and Toxicology, 1217 East Marshall Street, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298, USA.
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27
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D1/NMDA receptors and concurrent methamphetamine+ HIV-1 Tat neurotoxicity. J Neuroimmune Pharmacol 2012; 7:599-608. [PMID: 22552781 DOI: 10.1007/s11481-012-9362-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Accepted: 03/25/2012] [Indexed: 01/05/2023]
Abstract
The interactive effects of HIV-1 infection and methamphetamine (METH) abuse in producing cognitive dysfunction represent a serious medical problem; however, the neural mechanisms underlying this interactive neurotoxicity remain elusive. In this study, we report that a combination of low, sub-toxic doses of METH + HIV-1 Tat 1-86 B, but not METH + HIV-1 gp120, directly induces death of rodent midbrain neurons in vitro. The effects of D1- and NMDA-receptor specific antagonists (SCH23390 and MK-801, respectively) on the neurotoxicity of different doses of METH or HIV-1 Tat alone and on the METH + HIV-1Tat interaction in midbrain neuronal cultures suggest that the induction of the cell death cascade by METH and Tat requires both dopaminergic (D1) and N-methyl D-aspartate (NMDA) receptor-mediated signaling. This interactive METH+Tat neurotoxicity does not occur in cultures of hippocampal neurons, which are predominately glutamatergic, express very low levels of dopamine receptors, and have no functional dopamine transporter (DAT). Thus, the presence of a subpopulation of neurons capable of dopamine release/uptake is essential for METH+Tat induction of the cell death cascade. Overall, our results support the hypothesis that METH and HIV-1 Tat disrupt the normal conjunction of signaling between D1 and NMDA receptors, resulting in neural dysfunction and death.
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28
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Kumar AM, Fernandez JB, Singer EJ, Commins D, Waldrop-Valverde D, Ownby RL, Kumar M. Human immunodeficiency virus type 1 in the central nervous system leads to decreased dopamine in different regions of postmortem human brains. J Neurovirol 2010; 15:257-74. [PMID: 19499455 DOI: 10.1080/13550280902973952] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Human immunodeficiency virus type 1 (HIV-1) invades the central nervous system (CNS) shortly after infection and becomes localized in varying concentrations in different brain regions, the most vulnerable is the basal ganglia (BG). It is hypothesized that HIV-1-mediated neuropathogenesis involves degeneration of dopaminergic neurons in the substantia nigra and the loss of dopaminergic terminals in the BG, leading to deficits in the central dopaminergic activity, resulting in progressive impairment of neurocognitive and motor functions. In the era of highly active antiretroviral therapy (HAART), although the incidence of HIV-associated dementia (HAD) has decreased, the neurocognitive and neuropsychological deficits continue to persist after HAART. In this study, We investigated the impact of HIV-1 on dopaminergic activity with respect to concentrations of dopamine (DA) and homovanillic acid (HVA) in different regions of postmortem human brains of HIV-1-negative and HIV-1+ individuals and their relationship to neurocognitive impairment. We found that in HIV-1+ as well as HIV-negative cases, dopamine and HVA concentrations in ranged widely in different brain regions. In HIV-negative brain regions, the highest concentration of DA was found in putamen, caudate, substantia nigra, and the basal ganglia. In HIV-1+ cases, there was a significant decrease in DA levels in caudate nucleus, putamen, globus pallidus, and substantia nigra compared to that in HIV-negative cases. In HIV-1+ cases, a strong correlation was found between DA levels in substantia nigra and other brain regions. Concentration of HVA in HIV-negative cases was also highest in the regions containing high dopamine levels. However, no significant decrease in regional HVA levels was found in HIV-1+ cases. HIV-1 RNA load (nondetectable [ND] to log10 6.9 copies/g tissue) also ranged widely in the same brain regions of HIV-1+ cases. Interestingly, the brain regions having the highest HIV-1 RNA had the maximum decrease in DA levels. Age, gender, ethnicity, and postmortem interval were not correlated with decrease in DA levels. Profile of DA, HVA, and HIV-1 RNA levels in the brain regions of HIV-1+ individuals treated with HAART was similar to those not treated with HAART. A majority of HIV-1+ individuals had variable degrees of neurocognitive impairments, but no specific relationship was found between the regional DA content and severity of neurocognitive deficits. These findings suggest widespread deficits in dopamine in different brain regions of HIV-1-infected cases, and that these deficits may be the results of HIV-1-induced neurodegeneration in the subcortical regions of human brain.
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Affiliation(s)
- Adarsh M Kumar
- Department of Psychiatry and Behavioral Sciences, Miller School of Medicine, University of Miami, Miami, Florida 33101, USA.
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Abstract
Individuals suffering from human immunodeficiency virus type 1 (HIV-1) infection suffer from a wide range of neurological deficits. The most pronounced are the motor and cognitive deficits observed in many patients in the latter stages of HIV infection. Gross postmortem inspection shows cortical atrophy and widespread
neuronal loss. One of the more debilitating of the HIV-related syndromes is AIDS-related dementia, or HAD. Complete understanding of HIV neurotoxicity has been elusive. Both direct and indirect toxic mechanisms have been implicated in the neurotoxicity of the
HIV proteins, Tat and gp120. The glutamatergic system, nitric oxide, calcium, oxidative stress, apoptosis, and microglia have all been implicated in the pathogenesis of HIV-related neuronal degeneration. The aim of this review is to summarize the most
recent work and provide an overview to the current theories of HIV-related neurotoxicity and potential avenues of therapeutic interventions to prevent the neuronal loss and motor/cognitive deficits previously described.
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Affiliation(s)
- David R. Wallace
- Department of Pharmacology and Physiology and Department of Forensic Sciences, Center for Health Sciences, Oklahoma State University, Tulsa, OK 74107-1898, USA
- *David R. Wallace:
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Hu S, Sheng WS, Lokensgard JR, Peterson PK, Rock RB. Preferential sensitivity of human dopaminergic neurons to gp120-induced oxidative damage. J Neurovirol 2010; 15:401-10. [PMID: 20175694 DOI: 10.3109/13550280903296346] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The dopamine (DA)-rich midbrain is known to be a key target of human immunodeficiency virus (HIV)-1. Studies of simian immunodeficiency virus (SIV)-induced neuropathogenesis recently established that there is a major disruption within the nigrostriatal dopaminergic system characterized by marked depletion of dopaminergic neurons, microglial cell activation, and reactive astrocytes. Using a human mesencephalic neuronal/glial culture model, which contains dopaminergic neurons, microglia, and astrocytes, experiments were performed to characterize the damage to dopaminergic neurons induced by HIV-1 gp120. Functional impairment was assessed by DA uptake, and neurotoxicity was measured by apoptosis and oxidative damage. Through the use of this mesencephalic neuronal/glial culture model, we were able to identify the relative sensitivity of dopaminergic neurons to gp120-induced damage, manifested as reduced function (decreased DA uptake), morphological changes, and reduced viability. We also showed that gp120-induced oxidative damage is involved in this neuropathogenic process.
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Affiliation(s)
- Shuxian Hu
- Center for Infectious Diseases and Microbiology Translational Research, Division of Infectious Diseases and International Medicine, Department of Medicine, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA
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Kobylecki C, Silverdale MA, Varma A, Dick JPR, Kellett MW. HIV-associated Parkinsonism with levodopa-induced dyskinesia and response to highly-active antiretroviral therapy. Mov Disord 2010; 24:2441-2. [PMID: 19908326 DOI: 10.1002/mds.22860] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Muñoz-Moreno JA, Blanch Andreu J. [Neurocognitive disorders related to human immunodeficiency virus infection]. Med Clin (Barc) 2009; 132:787-91. [PMID: 19361818 DOI: 10.1016/j.medcli.2008.12.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2008] [Accepted: 12/16/2008] [Indexed: 11/30/2022]
Abstract
Disruption of neurocognitive functioning is one of most frequent complications in patients with HIV infection nowadays. The Highly Active Antiretroviral Therapy (HAART) has demonstrated an improvement associated with its use, although there are different works that show this improvement is achieved in a low proportion of individuals who initiate therapy. The most known characterization of neurocognitive dysfunction is the HIV-associated Dementia (HAD), yet there may also exist the asymptomatic neurocognitive impairment (ANI) or the Minor Cognitive-Motor Disorder (MCMD). This review describes the disorders related to HIV infection, and comments on possible interventions focused on the protection of neurocognitive functioning in HIV-infected people.
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Affiliation(s)
- José A Muñoz-Moreno
- Fundació Lluita contra la SIDA, Hospital Universitari Germans Trias i Pujol, Universitat Autònoma de Barcelona, Barcelona, España.
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Louboutin JP, Agrawal L, Reyes BAS, Van Bockstaele EJ, Strayer DS. HIV-1 gp120 neurotoxicity proximally and at a distance from the point of exposure: protection by rSV40 delivery of antioxidant enzymes. Neurobiol Dis 2009; 34:462-76. [PMID: 19327399 DOI: 10.1016/j.nbd.2009.03.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2008] [Revised: 02/26/2009] [Accepted: 03/04/2009] [Indexed: 01/21/2023] Open
Abstract
Toxicity of HIV-1 envelope glycoprotein (gp120) for substantia nigra (SN) neurons may contribute to the Parkinsonian manifestations often seen in HIV-1-associated dementia (HAD). We studied the neurotoxicity of gp120 for dopaminergic neurons and potential neuroprotection by antioxidant gene delivery. Rats were injected stereotaxically into their caudate-putamen (CP); CP and (substantia nigra) SN neuron loss was quantified. The area of neuron loss extended several millimeters from the injection site, approximately 35% of the CP area. SN neurons, outside of this area of direct neurotoxicity, were also severely affected. Dopaminergic SN neurons (expressing tyrosine hydroxylase, TH, in the SN and dopamine transporter, DAT, in the CP) were mostly affected: intra-CP gp120 caused approximately 50% DAT+ SN neuron loss. Prior intra-CP gene delivery of Cu/Zn superoxide dismutase (SOD1) or glutathione peroxidase (GPx1) protected SN neurons from intra-CP gp120. Thus, SN dopaminergic neurons are highly sensitive to HIV-1 gp120-induced neurotoxicity, and antioxidant gene delivery, even at a distance, is protective.
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Affiliation(s)
- Jean-Pierre Louboutin
- Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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Obermann M, Küper M, Kastrup O, Yaldizli O, Esser S, Thiermann J, Koutsilieri E, Arendt G, Diener HC, Maschke M. Substantia nigra hyperechogenicity and CSF dopamine depletion in HIV. J Neurol 2009; 256:948-53. [PMID: 19240951 DOI: 10.1007/s00415-009-5052-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2008] [Revised: 12/19/2008] [Accepted: 01/13/2009] [Indexed: 10/21/2022]
Abstract
Dopaminergic dysfunction is thought to play a pivotal role in human immunodeficiency virus (HIV)-related dementia. Decreased dopamine (DA) levels in the cerebrospinal fluid (CSF) and neuronal loss in the substantia nigra (SN) have been reported in HIV-infected patients, suggesting nigrostriatal damage. Structural changes detectable as hyperechogenicity in transcranial ultrasound (TCS) scans of the SN have been reported in patients with Parkinson's disease (PD) and other neurological conditions. In this study, we assessed the echomorphology of the SN in 40 HIV-positive patients compared to 40 age- and sex-matched healthy controls and correlated these findings with CSF levels of DA and the metabolites homovanillic acid (HVA) and 3,4-dihydroxy phenylacetic acid (DOPAC) and with neuropsychologic performance. We observed that the SN of HIV-infected patients was hyperechogenic relative to that of controls (0.07 +/- 0.05 vs. 0.04 +/- 0.07 cm(2); mean +/- SEM; P < 0.001) and that this SN hyperechogenicity was correlated with decreased DA levels in the CSF, decreased CD4 cell count, and an impaired performance in the psychopathology assessment scale (AMDP) subtest for drive and psychomobility. An association to CDC stage, duration of HIV infection, or presence of HIV dementia was not observed. Our results indicate changes in the nigrostriatal system in HIV-infected patients that are detectable as hyperechogenic SN precede prominent extrapyramidal symptoms and cognitive dysfunction.
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Affiliation(s)
- Mark Obermann
- Department of Neurology, University of Duisburg-Essen, Hufelandstr. 55, 45122, Essen, Germany.
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The role of host genetics in the susceptibility for HIV-associated neurocognitive disorders. AIDS Behav 2009; 13:118-32. [PMID: 18264751 DOI: 10.1007/s10461-008-9360-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2007] [Accepted: 01/22/2008] [Indexed: 12/23/2022]
Abstract
Despite progress in the treatment of the Human Immunodeficiency virus (HIV), there continues to be a high prevalence of infected individuals who develop neurocognitive deficits and disorders. Our understanding of the potential cause of HIV-associated neurocognitive disorders (HAND) continues to develop on many fronts. Among them is the study of host genetics. Here, we review the most current information regarding the association between host genetics and risk for HIV infection, AIDS, and HAND. We focus on the role of dopamine dysfunction in the etiology of HAND, and propose a number of genetic polymorphisms within genes related to dopaminergic functioning and other neurobiological factors that may confer vulnerability or protection against HAND.
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Mocchetti I, Nosheny RL, Tanda G, Ren K, Meyer EM. Brain-derived neurotrophic factor prevents human immunodeficiency virus type 1 protein gp120 neurotoxicity in the rat nigrostriatal system. Ann N Y Acad Sci 2008; 1122:144-54. [PMID: 18077570 DOI: 10.1196/annals.1403.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Human immunodeficiency virus type 1 (HIV-1) causes neuronal degeneration and, at a late stage, creates HIV-associated dementia (HAD) and other neurological abnormalities. Therefore, the need for neuroprotective agents is great. However, therapeutic agents that reduce HIV neurotoxicity are difficult to characterize and develop because rodents are not infected by HIV. This study was undertaken to develop an animal model of HIV neurotoxicity by using the HIV-1 envelope glycoprotein 120 (gp120). Vehicle or gp120 was injected acutely in the striatum of adult rats. gp120 produced loss of nigrostriatal neurons, as shown both by histochemical analysis of brain sections for apoptosis and biochemical determination of dopamine. The neurotrophin brain-derived neurotrophic factor (BDNF) delivered by a recombinant adeno-associated viral vector prevented gp120 toxicity. This study's results support the notion that gp120 produces a widespread neurotoxicity similar to that observed in HIV-positive individuals and that BDNF may be a suitable neuroprotective agent for HAD.
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Affiliation(s)
- Italo Mocchetti
- Department of Neuroscience, Georgetown University Medical Center, Research Bldg., 3970 Reservoir Rd., NW, Washington, DC 20057, USA.
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Santos E, Chaves J, Lima JL. Eyelid opening apraxia in an AIDS patient. Mov Disord 2008; 23:465-6. [PMID: 18067181 DOI: 10.1002/mds.21858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Brain-derived neurotrophic factor expression in the substantia nigra does not change after lesions of dopaminergic neurons. Neurotox Res 2008; 12:135-43. [PMID: 17967737 DOI: 10.1007/bf03033922] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Progressive and irreversible loss of specific neuronal cell populations is commonly seen in chronic neurodegenerative diseases such as Parkinson's disease (PD). Evidence is accumulating that apoptosis is a crucial cellular event responsible for the dysfunction and death of neurons in this disease. Thus, limiting apoptosis may prevent disease pathogenesis. Key to reducing apoptosis is the discovery of neuroprotective compounds that can be given to patients to minimize neuronal damage. In this manuscript, we reviewed the rationale of using an experimental strategy to provide neurotrophic support to injured neurons. Such rationale includes the increase of endogenous production of brain-derived neurotrophic factor (BDNF). BDNF is a potent inhibitor of apoptosis-mediated cell death and neurotoxin-induced degeneration of dopaminergic neurons. However, availability of BDNF may be reduced when dopaminergic neurons degenerate. Therefore, in this work, we have used several well-established neurotoxins for dopaminergic neurons, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, 6-OH-dopamine (6-OHDA), and the HIV protein gp120, to examine whether degeneration of nigrostriatal fibers alters BDNF expression. Our data show that these neurotoxins do not decrease the levels of BDNF in the substantia nigra, suggesting that up-regulation of BDNF synthesis by pharmacological means may be a viable therapy to slow down the progress of PD and other neurodegenerative diseases.
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Wallace VC, Blackbeard J, Pheby T, Segerdahl AR, Davies M, Hasnie F, Hall S, McMahon SB, Rice AS. Pharmacological, behavioural and mechanistic analysis of HIV-1 gp120 induced painful neuropathy. Pain 2007; 133:47-63. [PMID: 17433546 PMCID: PMC2706950 DOI: 10.1016/j.pain.2007.02.015] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2006] [Revised: 01/30/2007] [Accepted: 02/20/2007] [Indexed: 01/11/2023]
Abstract
A painful neuropathy is frequently observed in people living with human immunodeficiency virus type 1 (HIV-1). The HIV coat protein, glycoprotein 120 (gp120), implicated in the pathogenesis of neurological disorders associated with HIV, is capable of initiating neurotoxic cascades via an interaction with the CXCR4 and/or CCR5 chemokine receptors, which may underlie the pathogenesis of HIV-associated peripheral neuropathic pain. In order to elucidate the mechanisms underlying HIV-induced painful peripheral neuropathy, we have characterised pathological events in the peripheral and central nervous system following application of HIV-1 gp120 to the rat sciatic nerve. Perineural HIV-1 gp120 treatment induced a persistent mechanical hypersensitivity (44% decrease from baseline), but no alterations in sensitivity to thermal or cold stimuli, and thigmotactic (anxiety-like) behaviour in the open field. The mechanical hypersensitivity was sensitive to systemic treatment with gabapentin, morphine and the cannabinoid WIN 55,212-2, but not with amitriptyline. Immunohistochemical studies reveal: decreased intraepidermal nerve fibre density, macrophage infiltration into the peripheral nerve at the site of perineural HIV-1 gp120; changes in sensory neuron phenotype including expression of activating transcription factor 3 (ATF3) in 27% of cells, caspase-3 in 25% of cells, neuropeptide Y (NPY) in 12% of cells and galanin in 13% of cells and a spinal gliosis. These novel findings suggest that this model is not only useful for the elucidation of mechanisms underlying HIV-1-related peripheral neuropathy but may prove useful for preclinical assessment of drugs for the treatment of HIV-1 related peripheral neuropathic pain.
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Affiliation(s)
- Victoria C.J. Wallace
- Pain Research Group, Department of Anaesthetics, Pain Medicine and Intensive Care, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital Campus, 369 Fulham Road, London SW10 9NH, UK
| | - Julie Blackbeard
- Pain Research Group, Department of Anaesthetics, Pain Medicine and Intensive Care, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital Campus, 369 Fulham Road, London SW10 9NH, UK
| | - Timothy Pheby
- Pain Research Group, Department of Anaesthetics, Pain Medicine and Intensive Care, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital Campus, 369 Fulham Road, London SW10 9NH, UK
| | - Andrew R. Segerdahl
- Pain Research Group, Department of Anaesthetics, Pain Medicine and Intensive Care, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital Campus, 369 Fulham Road, London SW10 9NH, UK
| | - Meirion Davies
- Neurorestoration Group, Wolfson CARD, Kings College London, Guy’s Hospital Campus, London SE1 1UL, UK
| | - Fauzia Hasnie
- Pain Research Group, Department of Anaesthetics, Pain Medicine and Intensive Care, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital Campus, 369 Fulham Road, London SW10 9NH, UK
| | - Susan Hall
- Department of Anatomy and Human Sciences, Kings College London, Guy’s Hospital Campus, London SE1 1UL, UK
| | - Stephen B. McMahon
- Neurorestoration Group, Wolfson CARD, Kings College London, Guy’s Hospital Campus, London SE1 1UL, UK
| | - Andrew S.C. Rice
- Pain Research Group, Department of Anaesthetics, Pain Medicine and Intensive Care, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital Campus, 369 Fulham Road, London SW10 9NH, UK
- Corresponding author. Tel.: +44 020 8746 8156; fax: +44 020 8237 5109.
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Houff SA, Major EO. Neuropharmacology of HIV/AIDS. HANDBOOK OF CLINICAL NEUROLOGY 2007; 85:319-364. [PMID: 18808990 DOI: 10.1016/s0072-9752(07)85019-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
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Bachis A, Mocchetti I. Semisynthetic sphingoglycolipid LIGA20 is neuroprotective against human immunodeficiency virus-gp120-mediated apoptosis. J Neurosci Res 2006; 83:890-6. [PMID: 16477610 DOI: 10.1002/jnr.20780] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Apoptosis and neuronal atrophy are commonly seen in patients infected with the human immunodeficiency virus type 1 (HIV-1) in the late phase of infection. The HIV-1 envelope glycoprotein gp120 has been suggested to be a causal agent of neuronal loss. Therefore, blocking gp120 neurotoxicity may be an effective way to reduce the neuronal degeneration seen in HIV patients. Brain-derived neurotrophic factor (BDNF) prevents gp120-mediated apoptosis in cerebellar granule cells. However, BDNF poorly crosses the blood-brain barrier and therefore may not be a suitable therapy for HIV patients. LIGA20 is a semisynthetic sphingoglycolipid that may be a valid alternative to BDNF. In fact, it has been shown that LIGA20 mimics the neuroprotective properties of BDNF. The present study was undertaken to characterize the relative potency of LIGA20 to antagonize gp120-mediated apoptosis. Cerebellar granule cells were exposed to gp120IIIB (5 nM) or stromal-cell derived factor-1 (SDF), the natural ligand for the CXCR4 receptor to which gp120 binds, alone or in combination with LIGA20 (5 microM), and cell death/survival was determined 12 and 24 hr later by various markers of apoptosis. LIGA20 blocked the neurotoxic effect of gp120 and SDF. The neurotrophic effect of LIGA20 was reversed by K252a, a tyrosine kinase inhibitor used to block TrkB signaling, suggesting the involvement of TrkB activation. These findings provide the rationale for exploring the ability of compounds that mimic BDNF activity to reduce neuronal cell death in HIV-1-positive patients.
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Affiliation(s)
- Alessia Bachis
- Department of Neuroscience, Georgetown University Medical Center, Washington, DC 20057, USA
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Ghafouri M, Amini S, Khalili K, Sawaya BE. HIV-1 associated dementia: symptoms and causes. Retrovirology 2006; 3:28. [PMID: 16712719 PMCID: PMC1513597 DOI: 10.1186/1742-4690-3-28] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2006] [Accepted: 05/19/2006] [Indexed: 11/18/2022] Open
Abstract
Despite the use of highly active antiretroviral therapy (HAART), neuronal cell death remains a problem that is frequently found in the brains of HIV-1-infected patients. HAART has successfully prevented many of the former end-stage complications of AIDS, however, with increased survival times, the prevalence of minor HIV-1 associated cognitive impairment appears to be rising among AIDS patients. Further, HIV-1 associated dementia (HAD) is still prevalent in treated patients as well as attenuated forms of HAD and CNS opportunistic disorders. HIV-associated cognitive impairment correlates with the increased presence in the CNS of activated, though not necessarily HIV-1-infected, microglia and CNS macrophages. This suggests that indirect mechanisms of neuronal injury and loss/death occur in HIV/AIDS as a basis for dementia since neurons are not themselves productively infected by HIV-1. In this review, we discussed the symptoms and causes leading to HAD. Outcome from this review will provide new information regarding mechanisms of neuronal loss in AIDS patients.
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Affiliation(s)
- Mohammad Ghafouri
- Department of Neuroscience, Center for Neurovirology, Temple University School of Medicine, Pennsylvania 19122, USA
| | - Shohreh Amini
- Department of Biology, College of Science and Technology, Temple University, Philadelphia, Pennsylvania 19122, USA
| | - Kamel Khalili
- Department of Neuroscience, Center for Neurovirology, Temple University School of Medicine, Pennsylvania 19122, USA
| | - Bassel E Sawaya
- Department of Neuroscience, Center for Neurovirology, Temple University School of Medicine, Pennsylvania 19122, USA
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Neuroimmunity and the blood-brain barrier: molecular regulation of leukocyte transmigration and viral entry into the nervous system with a focus on neuroAIDS. J Neuroimmune Pharmacol 2006; 1:160-81. [PMID: 18040782 DOI: 10.1007/s11481-006-9017-3] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2005] [Accepted: 02/27/2006] [Indexed: 01/07/2023]
Abstract
HIV infection of the central nervous system (CNS) can result in neurologic dysfunction with devastating consequences in a significant number of individuals with AIDS. Two main CNS complications in individuals with HIV are encephalitis and dementia, which are characterized by leukocyte infiltration into the CNS, microglia activation, aberrant chemokine expression, blood-brain barrier (BBB) disruption, and eventual damage and/or loss of neurons. One of the major mediators of NeuroAIDS is the transmigration of HIV-infected leukocytes across the BBB into the CNS. This review summarizes new key findings that support a critical role of the BBB in regulating leukocyte transmigration. In addition, we discuss studies on communication among cells of the immune system, BBB, and the CNS parenchyma, and suggest how these interactions contribute to the pathogenesis of NeuroAIDS. We also describe some of the animal models that have been used to study and characterize important mechanisms that have been proposed to be involved in HIV-induced CNS dysfunction. Finally, we review the pharmacologic interventions that address neuroinflammation, and the effect of substance abuse on HIV-1 related neuroimmunity.
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Noorbakhsh F, Tang Q, Liu S, Silva C, van Marle G, Power C. Lentivirus envelope protein exerts differential neuropathogenic effects depending on the site of expression and target cell. Virology 2006; 348:260-76. [PMID: 16492386 DOI: 10.1016/j.virol.2005.10.044] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2005] [Revised: 07/30/2005] [Accepted: 10/26/2005] [Indexed: 12/27/2022]
Abstract
We investigated the neuropathogenic effects of feline immunodeficiency virus (FIV) envelope proteins in the context of both extracellular exposure and intracellular expression in feline neural cells. The envelope from the neurovirulent CSF-derived FIV V1 strain (V1-CSF) conferred infectivity to pseudotyped viruses in peripheral blood mononuclear cells (P < 0.01) in contrast to other cell types. Intracellular V1-CSF envelope expression in macrophages and microglia but not astrocytes resulted in the induction of host inflammatory genes contributing to neurotoxicity including IL-1beta, TNF-alpha, and indolamine 2',3'-dioxygenase (IDO) (P < 0.05) with concurrent neuronal death (P < 0.05). Upregulation of the endoplasmic reticulum stress genes was evident in brains from FIV-infected animals (P < 0.05) and in FIV-infected macrophages (P < 0.05) relative to controls. Intrastriatal implantation of an FIV envelope pseudotyped virus led to marked neuroinflammation and neuronal injury associated with neurobehavioral deficits (P < 0.01). Thus, lentivirus envelope proteins exert differential neuropathogenic effects through mechanisms that depend on the infected or exposed cell type.
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Nosheny RL, Bachis A, Aden SA, De Bernardi MA, Mocchetti I. Intrastriatal administration of human immunodeficiency virus-1 glycoprotein 120 reduces glial cell-line derived neurotrophic factor levels and causes apoptosis in the substantia nigra. ACTA ACUST UNITED AC 2006; 66:1311-21. [PMID: 16967504 DOI: 10.1002/neu.20288] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Uninfected neurons of the substantia nigra (SN) degenerate in human immunodeficiency virus (HIV)-positive patients through an unknown etiology. The HIV envelope glycoprotein 120 (gp120) causes apoptotic neuronal cell death in the rodent striatum, but its primary neurotoxic mechanism is still under investigation. Previous studies have shown that gp120 causes neurotoxicity in the rat striatum by reducing brain-derived neurotrophic factor (BDNF). Because glial cell line-derived neurotrophic factor (GDNF) and BDNF are neurotrophic factors crucial for the survival of dopaminergic neurons of the SN, we investigated whether gp120 reduces GDNF and BDNF levels concomitantly to induce apoptosis. Rats received a microinjection of gp120 or vehicle into the striatum and were sacrificed at various time intervals. GDNF but not BDNF immunoreactivity was decreased in the SN by 4 days in gp120-treated rats. In these animals, a significant increase in the number of caspase-3- positive neurons, both tyrosine hydroxylase (TH)-positive and -negative, was observed. Analysis of TH immunoreactivity revealed fewer TH-positive neurons and fibers in a medial and lateral portion of cell group A9 of the SN, an area that projects to the striatum, suggesting that gp120 induces retrograde degeneration of nigrostriatal neurons. We propose that dysfunction of the nigrostriatal dopaminergic system associated with HIV may be caused by a reduction of neurotrophic factor expression by gp120.
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Affiliation(s)
- Rachel L Nosheny
- Department of Neuroscience, Georgetown University Medical Center, Washington DC 20057, USA
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Li W, Galey D, Mattson MP, Nath A. Molecular and cellular mechanisms of neuronal cell death in HIV dementia. Neurotox Res 2005; 8:119-34. [PMID: 16260390 DOI: 10.1007/bf03033824] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The deaths of neurons, astrocytes and endothelial cells have been described in patients with HIV (human immunodeficiency virus) dementia. HIV-1 does not infect neurons; instead, neurotoxic substances shed by infected glia and macrophages can induce a form of programmed cell death called apoptosis in neurons. These neurotoxins include the HIV-1 proteins Tat and gp120, as well as pro-inflammatory cytokines, chemokines, excitotoxins and proteases. In this article we review the evidence for apoptosis of various cell types within the brain of HIV-infected patients, and describe in vitro and in vivo experimental studies that have elucidated the mechanisms by which HIV causes apoptosis of brain cells.
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Affiliation(s)
- W Li
- RT Johnson Division of Neuroimmunology and Neurological Infection, Department of Neurology, Johns Hopkins University, Baltimore, MD 21287, USA
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Jana A, Pahan K. Human immunodeficiency virus type 1 gp120 induces apoptosis in human primary neurons through redox-regulated activation of neutral sphingomyelinase. J Neurosci 2005; 24:9531-40. [PMID: 15509740 PMCID: PMC1955476 DOI: 10.1523/jneurosci.3085-04.2004] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) infection is known to cause disorders of the CNS, including HIV-associated dementia (HAD). HIV-1 coat protein gp120 (glycoprotein 120) induces neuronal apoptosis and has been implicated in the pathogenesis of HAD. However, the mechanism by which gp120 causes neuronal apoptosis is poorly understood. The present study underlines the importance of gp120 in inducing the production of ceramide, an important inducer of apoptosis, in human primary neurons. gp120 induced the activation of sphingomyelinases (primarily the neutral one) and the production of ceramide in primary neurons. Antisense knockdown of neutral (NSMase) but not acidic (ASMase) sphingomyelinase markedly inhibited gp120-mediated apoptosis and cell death of primary neurons, suggesting that the activation of NSMase but not ASMase plays an important role in gp120-mediated neuronal apoptosis. Similarly, the HIV-1 regulatory protein Tat also induced neuronal cell death via NSMase. Furthermore, gp120-induced production of ceramide was redox sensitive, because reactive oxygen species were involved in the activation of NSMase but not ASMase. gp120 coupled CXCR4 (CXC chemokine receptor 4) to induce NADPH oxidase-mediated production of superoxide radicals in neurons, which was involved in the activation of NSMase but not ASMase. These studies suggest that gp120 may induce neuronal apoptosis in the CNS of HAD patients through the CXCR4-NADPH oxidase-superoxide-NSMase-ceramide pathway.
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Affiliation(s)
- Arundhati Jana
- Section of Neuroscience, Department of Oral Biology, University of Nebraska Medical Center, Lincoln, Nebraska 68583, USA
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Nosheny RL, Bachis A, Acquas E, Mocchetti I. Human immunodeficiency virus type 1 glycoprotein gp120 reduces the levels of brain-derived neurotrophic factor in vivo: potential implication for neuronal cell death. Eur J Neurosci 2005; 20:2857-64. [PMID: 15579139 DOI: 10.1111/j.1460-9568.2004.03764.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Neuronal loss has been observed in post mortem brains of patients with human immunodeficiency virus type 1 (HIV-1). Experimental evidence has implicated HIV-1-derived envelope glycoprotein 120 (gp120) in the neuronal cell death observed in these patients. However, the intrinsic mechanisms by which gp120 causes neurotoxicity are still unknown. We have recently shown that the neurotoxic effect of gp120 in vitro is reduced by brain-derived neurotrophic factor (BDNF). We therefore tested the hypothesis that low levels of BDNF render neurons more sensitive to gp120. Gp120 was injected acutely into the striatum of BDNF heterozygous mice and wild-type littermates. BDNF heterozygous mice exhibited more apoptotic neurons in the striatum than wild-type mice, suggesting that BDNF is neuroprotective also in vivo. Because several neurodegenerative disorders are characterized by lack of trophic support, we tested the hypothesis that gp120 may cause apoptosis by reducing BDNF expression. Gp120 was injected acutely in the rat striatum and BDNF levels determined by a two-site immunoassay at various times after the injection. Gp120 elicited a dramatic decrease in BDNF protein levels by 24 h. Reduced BDNF levels were still present at 4 days. Cellular localization of BDNF immunoreactivity revealed that gp120 decreases BDNF immunoreactivity mainly in neuronal processes. This effect of gp120 precedes the peak of caspase-3 activation and neuronal cell death. We propose that one of the mechanisms whereby gp120 causes neurotoxicity is a reduction of the neurotrophic factor environment crucial for cell survival.
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Affiliation(s)
- Rachel L Nosheny
- Department of Neuroscience, Georgetown University, Washington, DC, USA
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Abstract
Movement disorders are a potential neurologic complication of acquired immune deficiency syndrome (AIDS), and may sometimes represent the initial manifestation of HIV infection. Dopaminergic dysfunction and the predilection of HIV infection to affect subcortical structures are thought to underlie the development of movement disorders such as parkinsonism in AIDS patients. In this review, we will discuss the clinical presentations, etiology and treatment of the various AIDS-related hypokinetic and hyperkinetic movement disorders, such as parkinsonism, chorea, myoclonus and dystonia. This review will also summarize current concepts regarding the pathophysiology of parkinsonism in HIV infection.
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Affiliation(s)
- Winona Tse
- Department of Neurology, Mount Sinai Medical Center, One Gustave L. Levy Place, Box 1052, New York, NY 10029, USA.
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