CLINICAL SIGNIFICANCE OF CELLULAR AND MOLECULAR COMPONENTS OF BLOOD-BRAIN-BARRIER

Abstract

The purpose of the study is to analyze the literature on the micromorphological and molecular features of the blood-brain barrier and then to establish the value of the obtained data for clinical disciplines in the context of diagnosis and explanation of the mechanisms of nerve tissue degeneration. Results and discussion. According to the danger of negative dynamics of the epidemiology of nervous system diseases among global population we decided to analyze the literature as for the role of cell and molecular components of the blood-brain barrier for diagnostics, explaining of pathogenesis and making a disease prognosis in cases of neuronal disorders (anatomy and physiology changes in blood-brain barrier in cases of neuron damaging is often mentioned in scientific works). In this article micromorphological and molecular structure of the blood-brain barrier were described. The role of components of neurovascular units for maintaining normal barrier functions of blood-brain barrier was also found out. We described pathomorphological and functional changes in blood-brain barrier in condition of central nervous system damages, such as increasing of blood-brain barrier permeability and disruption of its barrier functions, which are worsened by insufficient neurotoxin excretion and decreasing of energy supply of neurons. The role of perycytes and astocytes in neurodegeneration was also explained in this article. We paid much attention to molecular markers of components of neurovascular units (such as neuron-specific enolase, acidic glial protein, protein S100β, PDGFRβ, TYMP and the marker of blood-brain barrier integrity – albumin index) because of its possibility of being used as a method of evaluation of the functional state of cells (due to measurement of level of these molecules in serum or cerebrospinal fluid) before their interfering into pathological process and for evaluation of blood-brain barrier density. But unfortunately, changes of concentrations of the most part of them appeared to be not specific enough for being interpreted as increasing of blood-brain barrier permeability, but can be explained also by brain injury, neurodegeneration or severe cardiovascular failure. Another problem of analysis of biomarkers is difficulties with integrating of their measurement in clinical practice because the significant part of data was found out due to invasive methods of studying or even making an autopsy. This way or another, further researches of them are necessary. Conclusion. We suppose genetics studying to be a possible solution of mentioned problems. They can be not only a possible diagnostic method but an object of target therapy (for example, ABCB1 gene which encodes P-gp – the protein which could be considered as a transporter of neurotoxins or APOE4 gene which is supposed to correlate with the severity of neurodegeneration).