
Image Credit: Pasca lab
The neurological origins of mental illness continue to remain a mystery and along with it any potential treatments for these conditions. However, Dr. Sergiu Pasca and his team at Stanford University have come one step closer to unlocking these mysteries for schizophrenia, a mental disorder characterized by disruptions in thought processes, perceptions, emotional responsiveness, and social interactions.
A common genetic defect called 22q11.2 deletion syndrome, or 22q11DS for short, has been linked to an astonishing 30-fold increased risk for developing schizophrenia. With help from CIRM funding, Dr. Pasca and his team have linked this genetic defect to an electrical defect in nerve cells.
To look at this more closely, the Stanford team generated tiny clusters of brain cells, called cortical spheroids which contain brain nerve cells, in a dish using skin cells from 22q11DS carriers and those from normal patients. The team then measured the resting membrane potential of these nerve cells, which is the voltage difference between the inner and outer part of the cell. This measurement is important because it keeps the nerve cells ready to fire while also preventing them from firing at random.
Dr. Pasca and his team found abnormal levels of resting membrane potential in nerve cells in the cortical spheroids made from 22q11DS carriers. They also found that the the 22q11DS-derived nerve cells spontaneously fired four times as frequently as nerve cells derived from normal patients. What’s even more promising is that the team found that treating the 22q11DS-derived nerve cells with any of three different antipsychotic drugs effectively reversed the defects in resting membrane potential and helped in prevent spontaneous firing.

In a press release, Dr. Pasca elaborated more on the team’s findings.
“We can’t test hallucinations in a dish. But the fact that the cellular malfunctions we identified in a dish were reversed by drugs that relieve symptoms in people with schizophrenia suggests that these cellular malfunctions could be related to the disorder’s behavioral manifestations.”
The full results of this study were published in Nature Medicine.