UDC 612.822:616.831-092.18
This review presents an analysis and synthesis of the world literature, forming an up-to-date vision of the func- tional system of utilisation of end metabolites from the central nervous system, discussing impaired brain clearance in some neurodegenerative nosologies, as well as in strokes and traumatic brain injury. The central nervous system, lacking a classically conventional lymphatic system, requires alternative systems to clear the brain of potentially toxic cellular metabolic products. Over the past decade, world scientific sources have highlighted a new system of views, or the concept of the so-called glymphatic system, which makes it possible to drain the brain from extracel- lular harmful substances dissolved in the interstitium. Water channels such as aquaporin-4 (AQP4) are an important system component associated with neuropathologies such as Alzheimer's. The clearance of amyloid β (Aβ) and tau (tau) proteins associated with Alzheimer's disease, for example, is reduced due to the impaired function of the glym- phatic system in the absence of AQP. The detected changes in AQP4 expression associated with certain pathologies make it possible to predict that this water channel could be a potentially interesting pharmacological target. Recent studies in this context have also shown that biomarkers of traumatic brain injury are eliminated from the brain through the glymphatic system. The degree of suppression of glymphatic function under these conditions may affect the likely prognosis after traumatic brain injury. The obtained results predict the clinical value of pharmacological manipulations of the glymphatic system after acute traumatic brain injury. It has also been shown that with ageing, the processes of glymphatic drainage in the CNS decrease, which can contribute to the accumulation of misfolded and hyperphosphorylated proteins and thus make the brain susceptible to the development of neurodegenerative pathology. According to the experimental evidence presented in modern scientific sources, the concept of "acute or chronic glymphatic insufficiency" should be distinguished, and the issue of finding criteria for their correct as- sessment should be updated. It is known that the number of vasteosomes or starchy bodies can be considered a marker of chronic glymphatic insufficiency. According to the researchers, this knowledge will facilitate the study of glymphatic insufficiency and allow us to understand which moderating variables will critically impact the function- ing or failure of this system. Moreover, the fact that they are markers of chronic glymphatic insufficiency gives them promising clinical significance.