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Updated: May 2, 2026
A Rat Model of EcoHIV Brain Infection
Published on: January 21, 2021
Morphine increases hippocampal viral load and suppresses frontal lobe CCL5 expression in the LP-BM5 AIDS model
Virginia D McLane1, Ling Cao2, Colin L Willis2
1Graduate School of Biomedical Sciences and Engineering, University of Maine, Orono, ME 04473, USA; Department of Biomedical Sciences, College of Osteopathic Medicine, University of New England, Biddeford, ME 04005, USA; Center for Excellence in the Neurosciences, University of New England, Biddeford, ME 04005, USA.
Abstract:
Chronic opiate abuse accelerates the development of cognitive deficits in human immunodeficiency virus (HIV)-1 patients. To investigate morphine's effects on viral infection of the central nervous system, we applied chronic morphine treatment to the LP-BM5 murine acquired immunodeficiency syndrome (MAIDS) model. LP-BM5 infection induces proinflammatory cytokine/chemokine production, correlating to increased blood-brain barrier permeability. Morphine treatment significantly increased LP-BM5 viral load in the hippocampus, but not in the frontal lobe. Morphine reduced the chemokine CCL5 to non-infected levels in the frontal lobe, but not in the hippocampus. These data indicate a region-specific mechanism for morphine's effects on virally-induced neurocognitive deficits.
Insights
Chronic morphine use worsens cognitive deficits in HIV-1 patients by increasing viral load in the hippocampus. This study reveals region-specific effects of morphine on viral neuroinflammation and neurocognitive decline.
Area of Science:
- Neuroimmunology
- Virology
- Pharmacology
Background:
- Chronic opiate abuse exacerbates cognitive deficits in HIV-1 patients.
- HIV-1 infection of the central nervous system is associated with neuroinflammation and increased blood-brain barrier permeability.
- Murine acquired immunodeficiency syndrome (MAIDS) serves as a model for studying HIV-1-induced neurological complications.
Purpose of the Study:
- To investigate the effects of chronic morphine treatment on viral infection in the central nervous system.
- To examine the region-specific impact of morphine on viral load and neuroinflammation in the context of MAIDS.
- To elucidate the mechanisms underlying morphine's influence on virally-induced neurocognitive deficits.
Main Methods:
- Chronic morphine treatment was administered to the LP-BM5 MAIDS model.
- Viral load was quantified in specific brain regions (hippocampus and frontal lobe).
- Chemokine levels, specifically CCL5, were measured in brain tissues.
Main Results:
- Morphine treatment significantly increased LP-BM5 viral load in the hippocampus.
- No significant increase in viral load was observed in the frontal lobe.
- Morphine reduced CCL5 levels in the frontal lobe but not in the hippocampus.
Conclusions:
- Morphine exerts region-specific effects on viral load and neuroinflammation within the central nervous system.
- These findings suggest a localized mechanism by which morphine influences virally-induced neurocognitive deficits.
- Understanding these region-specific interactions is crucial for managing HIV-1 patients with comorbid opiate abuse.
