Vol 61, No 4 (2025)

In recent years, it has become clear that non-coding RNAs play an important role in regulating the development, metabolism and function of various organs. They play a pronounced regulatory role in various diseases and pathological conditions, including cerebral ischemia and reperfusion. Regulatory non-coding RNAs are mainly represented by long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs). Excessive activation of autophagy during severe cerebral ischemia and subsequent reperfusion leads to autophagic neuronal death, which, with apoptotic neuronal death, is known to be one of the main causes of brain injury in this disease. This review shows that regulatory noncoding RNAs can exert a neuroprotective effect by reducing the level of autophagy-related proteins (ATG proteins), which leads to inhibition and normalization of autophagy during brain ischemia and reperfusion. Thus, knockdown of one of the lncRNAs can lead to a significant increase in the level of microRNAs, which causes a subsequent decrease in the levels of messenger RNA (mRNA) of one of the ATG proteins and, as a consequence, a decrease in the level of the ATG protein itself. This results in inhibition of autophagy and reduction in brain damage from ischemia and reperfusion injury. Changes in miRNA and target protein mRNA levels occur due to the existence of complementary nucleotide sequences in lncRNA and miRNA, as well as in miRNA and mRNA of different ATG proteins, respectively. Thus, the final decrease in the level of ATG protein and inhibition of autophagy determine the protective effect of knockout of a number of lncRNAs (or circRNAs) during brain ischemia and reperfusion. Further study of the regulatory role of noncoding RNAs may help identify ways to counteract the brain-damaging effects of overactivation of autophagy and other abnormalities during brain ischemia and reperfusion.

Today, in an increasingly complex technogenic situation, the study of the effect of alternating magnetic fields (AMF) on biological objects is of particular relevance. The most sensitive to the action of magnetic fields is the nervous system. Using models on Drosophila melanogaster with different content of cryptochrome (CRY) (universal photo- and magnetosensor) in the test of conditional reflex suppression of courtship, the ways and mechanisms of the effect of weak AMF on memory and cognitive functions were studied. As a result of the study, a persistent repetitive effect of changing the behavior of Drosophila was found. It has been shown that in the light, a weak AMF stimulates the formation of medium-term memory in a mutant by the CG1848 gene for LIM kinase 1 agnts3, which is characterized by a violation of the learning processes and the formation of a memorable trace both under normal conditions and when exposed to a weak AMF in the darkness. CRY is the main target of exposure to weak AMF, since data have been obtained on the differential effect of light and dark on the formation of medium-term memory. The role of AMF in cognitive processes was revealed. The participation of CRY and AMF in the processes of memory formation will allow developing effective methods of non-invasive therapy of neuropathologies.