Structural Biochemistry/Schizophrenia

Schizophrenia is a severe neuro-psychiatric disease that affects approximately 1% of the world's population. It is characterized by a variety of symptoms that include hallucinations and delusions, and has five sub-categories for diagnosis: catatonic, residual, disorganized, undifferentiated and paranoid. The exact underlying biochemical mechanism of how schizophrenia is developed can be attributed to a multitude of factors, some of which are genetics, early environment, neurobiology and psychological and social processes.

A proposed chart describing the development of schizophrenia.

Albeit much research has been done in neurobiology and other fields, researchers have not yet isolated a single organic cause. Due to the multitude of factors that play a role in this disease, research can be approached in a variety of methods.

Symptoms

The symptoms of schizophrenia can be characterized by three symptom clusters: positive, negative and cognitive. The positive symptoms include any type of delusion or hallucination. Negative symptoms are a deficit of normal emotional responses. Oftentimes people experiencing negative symptoms can feel depressed and unmotivated. Lastly, cognitive symptoms refer to problems in attention, thought, perception, learning and memory.

Genetic Correlations with Schizophrenia

The most prominent causes of schizophrenia lies in genetics factors. People who have a family who have experienced psychosis or schizophrenia have a 5-10% chance of developing it themselves.

A number of genes have been shown to have correlation with those experiencing schizophrenia. One particular type of genetic mutation, copy number variation (CNV), have been seen in higher frequencies for those affected than in control groups. These genomic hot spots may one day be the key for treatments.

More recently, de novo mutations have also been regarded as a key component for the cause of schizophrenia.

Mechanism

The Dopamine Hypothesis of Schizophrenia The Dopamine Hypothesis of Schizophrenia is a model used by scientists to explain many of schizophrenic symptoms. The model claims that a high fluctuation of levels of dopamine may be responsible for hallucinations and delusions brought on by schizophrenics. This model has helped progress the development of antipsychotics, which are drugs that stabilize positive symptoms by acting as a dopamine-receptor antagonist.

Psychological Psychological factors may come into play and cause schizophrenia is an individual is under stress of confusing situations. Although much research has been done on whether childhood played a significant role, not much has been found.

Treatment

There has been a variety of antipsychotic drugs that are available for schizophrenics to take. These drugs work by blocking the dopamine receptors, thus curing the patient from many positive symptoms. However, not many drugs are available for negative or cognitive symptoms.

Future Treatment

With the advancement of whole genome sequencing as well as personalized medicine, it may be possible to better treat schizophrenics. With genes associated with schizophrenia, such as VIPR2, being discovered, scientists and doctors together may develop novel medicines to suppress excess hormones or other proteins.

It has been recorded that over a quarter of homeless people in the United States are schizophrenics. Although many have been diagnosed and put on medication, few stick to the treatment, resulting in a poor prognosis. Many schizophrenics have reported that antipsychotic drugs disable their normal day-to-day function. For this reason, many stop taking their medication. With personalized medicine, however, this may change. If each patient can be have a medicine tailored to their genome, resulting in minimal side effects, schizophrenics could return to a "normal" lifestyle.

Sources

"Schizophrenia" Concise Medical Dictionary. Oxford University Press, 2010. Oxford Reference Online. Maastricht University Library. 29 June 2010 prepaid subscription only Bell V, Halligan PW, Ellis HD. Explaining delusions: a cognitive perspective. Trends in Cognitive Science. 2006;10(5):219–26. doi:10.1016/j.tics.2006.03.004. PMID 16600666. Warner R. Recovery from schizophrenia and the recovery model. Curr Opin Psychiatry. 2009;22(4):374–80. doi:10.1097/YCO.0b013e32832c920b. PMID 19417668 Burns J. Dispelling a myth: developing world poverty, inequality, violence and social fragmentation are not good for outcome in schizophrenia. Afr J Psychiatry (Johannesbg). 2009;12(3):200–5. PMID 19894340.