Background Purpose of study is revealing significant differences in serum proteomes in schizophrenia and bipolar disorder (BD). Results Quantitative mass-spectrometry based proteomic analysis was used to quantify proteins in the blood serum samples after the depletion of six major blood proteins. Comparison of proteome profiles of different groups revealed 27 proteins being specific for schizophrenia, and 18 – for BD. Protein set in schizophrenia was mostly associated with immune response, cell communication, cell growth and maintenance, protein metabolism and regulation of nucleic acid metabolism. Protein set in BD was mostly associated with immune response, regulating transport processes across cell membrane and cell communication, development of neurons and oligodendrocytes and cell growth. Concentrations of ankyrin repeat domain-containing protein 12 (ANKRD12) and cadherin 5 in serum samples were determined by ELISA. Significant difference between three groups was revealed in ANKRD12 concentration ( p = 0.02), with maximum elevation of ANKRD12 concentration (median level) in schizophrenia followed by BD. Cadherin 5 concentration differed significantly ( p = 0.035) between schizophrenic patients with prevailing positive symptoms (4.78 [2.71, 7.12] ng/ml) and those with prevailing negative symptoms (1.86 [0.001, 4.11] ng/ml). Conclusions Our results are presumably useful for discovering the new pathways involved in endogenous psychotic disorders. Electronic supplementary material The online version of this article (10.1186/s12864-019-5848-1) contains supplementary material, which is available to authorized users.

This article describes the most likely classes of proteins and molecular processes that specifically characterize schizophrenic spectrum disorders such as simple and paranoid schizophrenia, schizotypal disorder, and acute polymorphic psychotic disorder (APPD). The identification of patients’ serum proteins was carried out using mass spectrometry. For patients with paranoid schizophrenia, the proteins responsible for translation and transcription are characteristic. A significant part of the proteins of patients with simple schizophrenia regulate the cell’s main metabolic and transport processes. These are proteins of the receptor system, vesicular transport, and extracellular matrix, which mainly carry out catabolic processes. The proteins of patients with schizotypal disorder mostly coincided with the classes of other patients, apart from chaperone proteins, which were not found in other studied groups. These proteins are mainly involved in anabolic processes. The main classes of proteins found in patients with APPD are responsible for the metabolism of nucleic acids. Active apoptosis processes were also revealed in these patients. These results from our basic knowledge about the molecular mechanisms of the pathogenesis of these disorders.

No abstract

No abstract