A new study published today in the journal Frontiers in Pharmacology found that cannabidiol (CBD) helped protect brain cells, reduce injury-related inflammatory responses and limit neuronal cell death in songbirds following brain injuries.
The research, conducted by scientists at East Carolina University’s Brody School of Medicine, provides new evidence that CBD may help protect the brain from secondary damage associated with traumatic brain injury.
The study was authored by Dylan A. Marshall, Karen A. Litwa and Ken Soderstrom, who investigated how CBD affects astrocytes, specialized brain cells that help maintain healthy neurons, regulate inflammation and support recovery following neurological damage.
Researchers used 16 adult male zebra finches, a species commonly used to study the neurological processes involved in vocal learning and communication. The birds were divided into two groups, with eight receiving CBD and eight receiving a control solution.
The CBD group received daily injections of 10 milligrams per kilogram of body weight for seven days, beginning six days before researchers created small, targeted injuries in a brain region responsible for learned vocal behavior. Brain tissue was examined 24 hours after the injuries.
Researchers found that CBD significantly increased the proportion of astrocytes in multiple brain regions involved in vocal learning and control.
In the injured region known as HVC, astrocytes accounted for 18.25% of measured cells among CBD-treated birds, compared with 12.92% in the control group. Similar protective effects were observed in two connected brain regions, known as RA and Area X.
CBD treatment was also associated with substantially less neuronal apoptosis, a form of programmed cell death that can occur following brain injury.
In the injured HVC region, 15.99% of neurons in the control group showed signs of apoptosis, compared with just 3.96% among CBD-treated birds. That represents an approximately 75% lower proportion of neurons displaying this marker of cell death.
Researchers also documented reductions in cellular stress responses and changes in genes associated with inflammation. CBD suppressed several markers linked to reactive astrocytes, including C3, S100A10 and aromatase, while increasing expression of genes involved in antioxidant defenses and brain-cell metabolism.
These findings suggest CBD may protect brain tissue through multiple mechanisms, including preserving supportive brain cells, reducing inflammatory activity and strengthening the brain’s ability to respond to oxidative stress.
The researchers said the findings build on earlier experiments showing that CBD reduced inflammatory cytokines, limited synaptic damage and accelerated recovery of learned vocal patterns in zebra finches following similar injuries.
The new study focused specifically on identifying cellular mechanisms that might explain those previously observed benefits.
The researchers noted that neurological injuries can trigger inflammatory processes that continue well after the initial trauma, potentially contributing to cognitive impairment and other long-term complications.
The researchers concluded that the findings strengthen the case for further investigation of CBD as a potential neuroprotective treatment, particularly for reducing secondary brain injury and protecting neurological functions involved in communication.
