Schizophrenia is a chronic mental disorder with no definite cure yet. It means that someone suffering from the disease will have to endure it for their entire life with only a few ways to manage. Compared to other mental conditions like depression, schizophrenia is not very common; about 7 in every 1,000 people in the U.S. have it. The lack of a cure stems from the fact that researchers have to be able to pin down an exact cause for the condition, which is yet to take place.
Altered brain chemistry, genetics, and environmental factors are some of the underlying elements that are associated with schizophrenia. A schizophrenic loses touch with reality, experiences difficulty with mental acuity and memory.
Confused thoughts, auditory hallucinations, and withdrawal from social interactions are just some of the other symptoms of the disorder. Schizophrenia symptoms are categorized as positive, like hallucinations and delusions or negative such as being withdrawn and lacking motivation. As the disorder progresses, the symptoms can be quite debilitating.
Over the years, researchers have been trying different treatments to minimize the effects of these symptoms and one of them is the use of compound serotonin. In one study, researchers explained that a new class of compounds could be used to treat schizophrenia. The compounds work on a serotonin receptor that was not previously targeted. Researchers claim that this treatment is more effective than conventional options and presents fewer side effects than psychotics.
Relationship between Serotonin and Schizophrenia
Serotonin, also called 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter and is accredited to feelings of happiness and well-being in humans. Current treatments focus on two areas of the brain, the dopamine and serotonin receptors, which are responsible for various cognitive functions.
Compromised cognitive functions are some of the manifestations of borderline schizophrenia disorder, which is how the effectiveness of serotonin receptor antagonists is justified. Symptoms such mood swings, aggression issues, and diminished attention levels are all associated with serotonin levels in the brain.
Arguably, the use of serotonergic medication can have an effect on the psychopathology of schizophrenia. In fact, most of the antidepressants and psychotics work by increasing the levels of dopamine and serotonin.
During the earlier years of researching schizophrenia, researchers concentrated on the effects that serotonin may have on brain function and how blocking certain receptors can help treat the disease. Studies were conducted on serotonergic agonists, antagonists, and precursors but the results were not promising. The interest in how 5-HT deficiency influences schizophrenic symptoms died down when researchers started focusing more on the neurotransmitter, dopamine.
The Serotonin Theory
A recent study that was led by William C. Wetsel targets the 5-HT2C receptor sign, a mixture of several compounds. Past attempts to inhibit the 5-HT2C have not been successful because researchers were not able to create a cocktail of drugs that were good enough to react specifically with that receptor. By testing mice, the study revealed that the class of drugs was able to reduce the hyperactivity that comes with acute psychosis.
Side effects such as involuntary movements of the extremities were relatively low. This study may have ignited the debate of whether serotonin receptor antagonists are effective in managing schizophrenia but it is imperative to factor in that the results were in animals. The point of manipulating the serotonergic system is to ameliorate the positive and negative symptoms of schizophrenia.
Clozapine and other 5-HT Antagonists
The renewed interest in the theory that serotonergic drugs are effective in managing schizophrenia was fueled by the entry of psychotics such as clozapine, risperidone, and olanzapine. Clozapine is characterized by superior antipsychotic qualities, which are attributed to its antagonistic properties towards the 5-HT2A, 5-HT2C, and 5-HT3 receptors.
The drug is only moderately antagonistic towards the dopamine D2 receptor. These classes of drugs, which are better serotonin antagonists, have been proven to tackle schizophrenic symptoms more effectively than conventional psychotics that are primarily dopamine antagonists. Weight gain, motor seizures, and myoclonic seizures are some of the known side effects of clozapine.
It is clear that some of the cognitive disturbances that are present in a person with schizophrenia are associated with serotonin deficiency. Abnormalities of the brain structure such as a decreased prefrontal and medial temporal lobe, as well as enlarged ventricles are also attributed to schizophrenia.
However, other mental conditions such as mood disorders have similar characteristics. A direct relationship has not been established between serotonin and schizophrenia, which is why there are still doubts about the efficiency of some serotonergic medications.
The whole argument is based on the premise that schizophrenia is caused solely by altered brain chemistry. However, debate still exists as to the contribution of the physical being towards mental illness. Studies into the role of serotonin in the psychological disorder continue in a bid to ascertain the exact impact of serotonergic drugs. At the moment, new antipsychotic agents, which are 5-HT2A antagonists, are doing a decent job of managing treatment-resistant schizophrenia and the class of negative symptoms.