A Better Treatment for Schizophrenia
Dr. Fang Liu, Senior Scientist in the Centre for Addiction and Mental Health (CAMH) Campbell Family Mental Health Research Institute and Professor in the Department of Psychiatry, is developing targeted peptide treatments that are leading to the development of better drugs to treat mental illnesses, such as depression and schizophrenia. “Compared to current medications, these targeted peptide treatments have the potential to reduce side effects for people living with depression and schizophrenia,” says Dr. Liu. “Side effects can discourage people from taking the drugs that are critical for their mental health. We are going to change this.”
Better Treatment for Schizophrenia
Current medications that treat schizophrenia work by blocking the actions of dopamine, a neurotransmitter, on receptors of the brain. This blockage can alleviate symptoms, but it can also interfere with necessary neurotransmitter signalling, leading to side effects like slow gait, stiffness and tremor.
In search of a solution that would treat the symptoms of schizophrenia with minimal side effects, Dr. Liu discovered that brain receptors associated with schizophrenia (called dopamine D2 receptors) combine with a protein called Disrupted-In-Schizophrenia (DISC1), and this combined protein is elevated in schizophrenia.
Armed with this new knowledge, Dr. Liu has generated a peptide that prevents the binding of DISC1 with D2 receptors. Disrupting the formation of this protein has demonstrated antipsychotic effects in preclinical models, without side effects.
“Targeted peptide treatments have the potential to reduce side effects for people living with depression and schizophrenia. Side effects can discourage people from taking drugs that are critical for their mental health. We are going to change this.”
Nasal Spray Depression Treatment
Dr. Liu has also developed a highly targeted protein peptide for treating depression that has minimal side effects. This protein peptide could not cross the blood-brain barrier when taken orally.
Her team, supported by the Canadian Institutes of Health Research (CIHR), has found a non-invasive, alternative way to deliver the peptide treatment: a first-of-its-kind nasal spray. In preclinical models, the spray relieved depression-like symptoms with few side effects.
Dr. Liu continues to explore and perfect these and other highly targeted therapeutic approaches in her lab. As she works toward collaboration with industry partners, Dr. Liu is optimistic that her research will translate to clinical advances.