Approximately 24 million people on Earth suffer from schizophrenia. This mental disorder is accompanied by hallucinations, impaired thinking and behavior, as well as emotional reactions. The exact causes of the disease are still not clear, but studies indicate that schizophrenia may be associated with a violation of the amount and composition of lipids in the brain. These molecules are part of cell membranes and are also involved in energy storage and signal transmission between cells. Therefore, changes in lipid metabolism can disrupt the integrity of cell membranes and thus lead to malfunction of neurons and cognitive disorders. However, some studies clearly show changes in lipid metabolism in brain tissues. At the same time, most of them explore cortex (the area where the bodies of nerve cells are located), while the white matter (the area with the processes of neurons) remained practically unexplored.

Researchers from the Skolkovo Institute of Science and Technology (Moscow), Lomonosov Moscow State University (Moscow), and colleagues from the N. A. Alekseev Psychiatric Clinical Hospital No. 1 of the Moscow Department of Health and the V. P. Serbsky National Medical Research Center for Psychiatry and Narcology of the Russian Ministry of Health analyzed how the lipid composition and the activity of genes changes in the white matter of the brain in schizophrenia.

The authors studied 14 samples of the corpus callosum of the brain, a region of white matter where nerve fibers intertwine between the right and left hemispheres and thereby provide the exchange of information and signals. Seven samples were taken from healthy people, and seven more from patients with schizophrenia.

The researchers analyzed the amount, distribution, and composition of lipids in corpus callosum tissue. The team used high-performance liquid chromatography with mass spectrometry, a method that allows detecting a large number of compounds in tissue samples at once in a single analysis.

It turned out that the corpus callosum in patients with schizophrenia contains fewer lipids, which are part of the cell membranes and the myelin (“insulating”) membrane on the processes of nerve cells, than in healthy people. This group also had reduced levels of lipids used by cells as an energy source.

The team also studied the activity of 14,254 genes in the corpus callosum of healthy people and patients with schizophrenia. The research discovered 1,202 genes that had a significant difference in activity between the studied groups. They were divided by function into four classes — one of them turned out to be associated with lipid metabolism. Thus, changes in gene activity may be one of the reasons for the revealed differences in lipid composition.

“The obtained data enables us to comprehend the molecular changes that take place in the brain as schizophrenia develops. Knowing them is inportant for developing new diagnostic methods. Identifying biomarkers based on blood lipid composition can help diagnose schizophrenia at an early stage, for example,” says Maria Osetrova, a researcher at the Skoltech Neuro Center, a co-author of the study supported by grants from the Russian Science Foundation.