Treatment of Cognitive and Negative Symptoms in Schizophrenia With N-acetylcysteine
Status:
Active, not recruiting
Trial end date:
2022-01-31
Target enrollment:
Participant gender:
Summary
The purpose of this study is to attempt to treat cognitive and negative symptoms of
schizophrenia, with the nutritional supplement N-acetylcysteine (NAC).
Schizophrenia is a chronic mental disorder that affects approximately 65 million people
worldwide, and causes significant disability and suffering. Patients with schizophrenia often
hear voices and have persecutory delusions. Though these are the most recognizable features
of the illness, the deficits most closely linked to disability are known as cognitive
deficits and negative symptoms. Cognitive abilities refer to the ability to perform mental
tasks that require focus and attention, and also include memory and verbal skills. Negative
symptoms refer to a lack of interest in the world, and decreased social interactions. In our
study, the investigators aim to improve these symptoms and deficits by targeting the
glutamate system.
Glutamate is the major excitatory neurotransmitter in the brain, and its regulation is
abnormal in schizophrenia: glutamate levels are too low at some receptors, and too high at
others. As well, free radicals surrounding glutamate receptors also interfere with their
proper function. N-acetylcystine (NAC) is a safe and widely-available dietary supplement that
may restore glutamate to its correct levels in the brain, and may also help protect the brain
from antioxidant damage.
In our study, patients with schizophrenia will be randomly assigned to receive either NAC or
placebo for 8 weeks. Brain levels of glutamate and an important antioxidant, glutathione,
will be measured before and after treatment, using a neuroimaging technique known as magnetic
resonance spectroscopy. Cognitive and negative symptoms will also be assessed before, during
and after treatment. The investigators hypothesize that glutamate and glutathione will be
normalized in patients' brains, and that their negative and cognitive symptoms will be
improved, too.