Transcriptome profiling of Basal ganglia tissue from chronically SIV infected rhesus macaques

The dysregulation of the microbiota-gut-brain axis (MGBA) in people living with HIV (PLWH) consequent to gastrointestinal dysfunction (dysbiosis) can lead to neuroinflammation and persistent cognitive impairment, which underscores the need for new treatments. Here, we show that delta-9-tetrahydrocannabinol (THC) reduced neuroinflammation and microbiome alterations and enhanced plasma endocannabinoid, endocannabinoid-like and indole-3-propionate levels in chronically SIV-infected rhesus macaques. Long-term low-dose THC potently blocked expression of genes associated with type I interferon responses and excitotoxicity (SLC7A11) and enhanced protein expression of WFS1 (endoplasmic reticulum stress) and CRYM (oxidative stress) in basal ganglia. Additionally, THC successfully countered miR-142-3p mediated suppression of WFS1 via a CB1R mediated mechanism in HCN2 neuronal cells. Most importantly, THC increased the relative abundance of Firmicutes and Clostridia including IPA producersing C. botulinum, C. paraputrificum, C. cadaveris and butyrate producersing C. butyricum, Faecalibacterium prauzsnitzii and Butyricicoccus pullicaecorum in the colon. This study highlights low-dose THC as a potential disease-modifying agent that can positively modulate the MGBA by concurrently reducing neuroinflammation and promoting the growth of gut microbial species that produce neuroprotective metabolites like indole-3-propionate in PLWH HIV and other neurodegenerative diseases, thus meriting clinical trials. Overall design: Basal ganglia tissue mRNA profiles of uninfected control (n=5) and chronically SIV-infected rhesus macaques that were treated with vehicle (n=6) or delta-9-tetrahydrocannabinol (THC) (n=6) were generated by deep sequencing using Illumina.