Astrogliosis Occurs Selectively in Amygdala of Adolescent Primate and Rodent Following Daily Δ9-Tetrahydrocannabinol, Prevented by Cannabidiol Co-Treatment.
Biological psychiatry global open science July 1, 2025 Yalin Sun, Meenalochani Sivasubramanian, Marija Milenkovic et al.
Adolescent cannabis use increases risk for neuropsychiatric disorders, possibly through amygdala dysfunction. Chronic THC treatment in male adolescent nonhuman primates and rats disrupted sleep and increased anxiety-related behavior. THC activated proinflammatory glial cells (astrocytes) exclusively in the adolescent amygdala, upregulating GFAP and complement factor-B, effects absent in adults or other brain regions. THC also reduced synaptic plasticity markers stathmin-1 and NrCAM. Co-administered cannabidiol prevented astrocyte inflammation but did not restore plasticity markers. Astrogliosis correlated with fragmented sleep, attenuated plasticity markers with anxiety. Elevated CB1R expression in the maturing brain was astrocyte-localized in the amygdala, linking THC to unique adolescent amygdala vulnerability.