A lot of research goes into the disease schizophrenia. It is a psychological condition, which involves the disruption of thought, interpretation of sensory perceptions and emotional activity. It is a development disorder, which we still do not completely know the cause of. However, we do know that hereditary and environmental factors play a part in maldevelopment in the brain. A new study has examined specific cells in the brain, in the hope of finding a cause as to why some people develop schizophrenia and others do not.
Defective glial cells can result in schizophrenia
The specific cells that the study examined are called glial cells, and they function as a kind of “support cell” for our neurons. They help the neurons to keep in place, ensure oxygen and nutrition for the neurons, isolate the neurons from each other, destroy harmful foreign objects, and remove the neurons which die with time. It is thus an important function, because it maintains the brain’s functionality throughout one’s life, by supporting and protecting neurons in the central nervous system in the brain.
A very important function of glial cells is their ability to form a protective layer of fat, called myelin, around the neuron´s long “outputs”. It is through this long output that the signal of the neuron runs through. The myelin-layer makes the neuron capable of sending a signal faster to the next neuron in the brain. If a glial cell contains errors in its genetic material, called DNA, it can result in a decreased production of myelin. A lack of myelin results in an incorrect development of the neural network, which is found in the brain. It is a network, where signals are sent between neurons from different parts of the brain. This has been shown to be a very important cause in the development of schizophrenia. This knowledge comes from the new study which, among others, has been carried out by researchers from the University of Copenhagen.
Mice with human glial cells
The results of the study indicate that defective glial cells, which thus lack the ability to carry out their purpose correctly, are a primary cause of the development of schizophrenia. This conclusion is based on research performed on mice. First, the researchers took skin cells from individuals who had developed schizophrenia at a very young age. They made these cells form stem cells. A stem cell is a type of cell, which can divide itself and form into any type of cell in the body, including glial cells. The precursor to glial cells were introduced into the brain of small, newly born mice and developed into glial cells. Afterwards they outcompeted the mice’s own glial cells. The brain of these mice thus consisted of neurons from mice and glial cells from humans with early onset schizophrenia.
The researchers saw that these glial cells did not work properly. The development of the cells was delayed and their ability to produce myelin was greatly reduced, which lead to a too low production. This resulted in a disturbed wiring of signals in the neurons. The researchers could thus show that glial cells in schizophrenics are defective in the area which is responsible for myelin production. Reduced myelin has previously been shown to be associated with schizophrenia.
Mice with schizophrenic behavior
The researchers tried to subject their lab-mice to a series of tests that examined the behavioral patterns of the mice. Here they could observe that the mice that had human glial cells from people with schizophrenia were more fearful, anxious, asocial and had several cognitive deficiencies compared to mice which had human glial cells transmitted from healthy people.
The reason why schizophrenics have defective glial cells
Additionally, the researchers also found several genetic defects in these mice, which could be part of the explanation as to why glial cells could not produce enough myelin. These genetic defects affected the 'potassium pumps' of the glial cells - small transport units in the cell that can send potassium into and out of the cell. Defective potassium pumps play a major role in the functions of the cells and can therefore make the cells unable to produce myelin.
The study provides a basis for better treatment options
Researchers behind the study suggest that these results can contribute to better knowledge which can benefit the development of new treatment options for patients with the disease. Because schizophrenia is unique to humans, researchers have been limited in terms of investigating the disease but with these results, researchers can accelerate the process of testing new remedies and treatment options for schizophrenia.
There are different types of drugs that are approved for medical use, and which work on the cell defects seen in glial cells from schizophrenic people. The researchers are now testing these drugs as they may potentially be candidates for the treatment of schizophrenia. Among other things, these substances work on the defective potassium pump. The substances are now being tested on mice to see if they can form functional potassium pumps and prevent the development of schizophrenia. Alternatively, researchers are considering replacing defective glial cells with healthy glial cells, thus preventing the development of the disease.
The results of the research thus provide hope for new treatment options for patients, which is a step in the right direction. There are many patients who either sparingly or not at all benefit from their medical treatment.
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