Brain tissue analysis found that CB1 and CB2 receptors were differently expressed in people with HIV-associated cognitive disorders compared to those without, with CB1 levels correlating with memory and processing speed deficits.
HIV researchers, neuroimmunologists, medical cannabis researchers
CB1 receptor levels negatively correlated with memory and processing speed in HIV-positive brains
What the researchers found
Immunoblot analysis showed CB1 and CB2 receptors were differentially expressed in frontal cortices of HAND versus neurocognitively unimpaired HIV-positive brains. CB1 expression negatively correlated with memory and processing speed. In HAND brains, CB1 shifted from neuronal processes to cell bodies and showed increased colocalization with astrocytes.
Why it matters
With HIV-associated cognitive disorders persisting despite antiretroviral therapy, identifying endocannabinoid system changes could open new therapeutic targets for the estimated 50% of people with HIV who experience some degree of cognitive impairment.
The numbers in context
CB1 and CB2 differentially expressed in HAND vs NUI brains; CB1 expression negatively correlated with memory and information processing speed; CB1 redistributed from neuronal processes to soma in HAND; increased CB1 colocalization with astroglial marker in HAND.
How the study worked
Cross-sectional biochemical and immunohistochemical analyses of CB1 and CB2 receptor expression in post-mortem brain specimens from people with HIV, comparing those with and without HIV-associated neurocognitive disorders.
What this study cannot tell us
Post-mortem brain analysis cannot establish causation; small sample sizes; cross-sectional design; antiretroviral medication effects not fully controlled; cannot determine if receptor changes preceded or resulted from cognitive decline.
How to read the evidence
Post-mortem brain analysis providing preliminary evidence of endocannabinoid system involvement in HIV-associated cognitive disorders.
When this study was published
Published in 2021.
The bigger picture
The redistribution of cannabinoid receptors in HIV-affected brains suggests that the endocannabinoid system is involved in the cognitive impairment that persists despite viral suppression, potentially explaining why some people with HIV report cognitive benefits from cannabis use.
Questions still open
- Could cannabinoid-based therapies improve cognitive function in people with HIV? Does cannabis use by people with HIV normalize the receptor redistribution seen in HAND?
Common questions
How does HIV affect cannabinoid receptors in the brain?
Could cannabis help HIV-related cognitive problems?
Read the original research
Alterations in Brain Cannabinoid Receptor Levels Are Associated with HIV-Associated Neurocognitive Disorders in the ART Era: Implications for Therapeutic Strategies Targeting the Endocannabinoid System.
Viruses, 13(9)
Citation
Swinton, Mary K; Sundermann, Erin E; Pedersen, Lauren; Nguyen, Jacques D; Grelotti, David J; Taffe, Michael A; Iudicello, Jennifer E; Fields, Jerel Adam. (2021). Alterations in Brain Cannabinoid Receptor Levels Are Associated with HIV-Associated Neurocognitive Disorders in the ART Era: Implications for Therapeutic Strategies Targeting the Endocannabinoid System.. Viruses, 13(9). https://doi.org/10.3390/v13091742
Explore the wider topic
- How THC Affects Your Amygdala: The Brain's Threat Detector and Cannabis
- The Anandamide Connection: Your Body's Natural Bliss Molecule
- How Long for Cannabinoid Receptors to Return to Normal
- Cannabis and the Developing Brain: What Every Teenager (and Parent) Should Know
- Why Can't I Enjoy Anything Without Weed? The Science Behind It
- Dopamine Recovery After Quitting Weed: What the Science Says
- The Endocannabinoid System Explained Simply: What It Does and Why It Matters
- Your Endocannabinoid System Explained: Why Withdrawal Happens
- Your Nervous System After Quitting Weed: Fight or Flight
- Using Weed Under 18: What It Does to Your Developing Brain
- What THC Does to Your Brain: Why Withdrawal Happens
- THC and Your Prefrontal Cortex: What Cannabis Does to Your Decision-Making Brain
- Weed, Cortisol, and Stress: What Cannabis Does to Your Stress Hormones
- Weed and Memory: What the Science Says About THC and Your Hippocampus
- Weed and Motivation: Is Amotivational Syndrome Real?
- Weed and Your Nervous System: What THC Actually Does to Your Brain and Body
- How Weed Rewires Your Reward System (And How to Reset It)