In the study, the researchers genetically engineered mice in order to shed light on BDNF's role in the brain. Mice with no BDNF died shortly after birth. In addition, the BDNF-deprived mice appeared noticeably more aggressive and impulsive. Further, he adds, the mice had become almost twice normal size because of compulsive, almost bulimic eating. There's an impulsive quality to their eating and to their aggression that ties into the damaged serotonin system.
Impulse control is a well-documented casualty of low serotonin.
This same impulsivity is seen in depressed people who commit suicide, the researchers say, which suggests these mice could be a model for testing drugs to lessen suicide or bulimia. When the researchers treated the mice with Prozac, which increases available serotonin, the fighting and compulsive eating stopped. Because one of the major side effects of the most potent schizophrenia medications is obesity with a bulimic aspect, says Koliatsos, the study may offer ways to tone down that behavior while maintaining the therapy's helpful effects. Md. The work was funded by grants from the National Cancer Institute, the National Institute of Mental Health and a Javits Neuroscience Investigator Award. Footage showing overweight, aggressive BDNF-deprived mice in action is available.