Ketamine, a common anesthetic, has shown promise as a potential treatment for severe depression. Researchers from HHMI’s Janelia Research Campus, Harvard, and Johns Hopkins have made significant breakthroughs in understanding how the drug works, particularly its effects on brain cells called astroglia.
In a new study published in Neuron, scientists used zebrafish to test the antidepressant properties of ketamine. The results suggest that the drug suppresses a specific behavior known as “giving up” or futility-induced passivity by overstimulating astroglia. This finding has implications for understanding how antidepressants work in the brain and could lead to the development of safer and more effective treatments.
The researchers created a virtual reality system to test the effects of ketamine on zebrafish, which exhibit this “giving up” behavior when their swimming becomes futile. The team found that exposure to ketamine suppressed this behavior by increasing astroglia activity and reducing the sensitivity of these cells to futility signals.
Similar results were obtained in mice, suggesting that astrocyte engagement during intense arousal states is evolutionarily conserved across species. This finding increases the likelihood that comparable mechanisms exist in humans, potentially providing new insights into the treatment of depression.
The study highlights the potential role of astroglia in depression and suggests that ketamine may work by modulating brain state through neuron-astroglial communication. While further research is needed to fully understand the effects of ketamine on human brains, these findings provide a promising lead for future investigations into this complex disorder.
Source: https://www.genengnews.com/topics/translational-medicine/ketamine-keeps-zebrafish-from-giving-up-by-overstimulating-astroglia