Vol 9, No 6 (2019)

The article describes a concept of epigene networks that attempts to clarify the phenomenon of heredity and presents the results of long-term studies of the control gene and epigene networks in which the authors used an integrative approach with the tools of mathematical biology, cybernetics, genetic engineering, and bioinformatics. Epigene networks are control gene networks with epigenetic properties or those containing epigenes. By epigene, we mean special hereditary units with at least two modes of functioning of the genes subordinate to them that are capable of maintaining each of the modes in a successive series of generations. Epigenes are the units of functional hereditary memory; they perform a special role in ontogeny and phylogeny. Epigenetic systems can be designed and synthesized experimentally. One such systems is a two-component, stationary epigene with specified and controlled inherited dynamic properties that functions in vivo. Artificial epigenetic constructions can serve as models of the mechanisms of differentiation and cellular memory and can be used as bacterial biosensors. The generalized threshold models of natural and synthetic molecular genetic systems for the control of gene expression have both analytical and predictive value.

This review considers the potential mechanisms of radiomitigative effect of radioprotective drugs in interaction with pathophysiological processes accompanying radiation injury to tissues at the earliest stages of its development. Radiomitigators affect bodily systems throughout the development of primary radiation stress and inflammatory process upon the realization of radiation injury during the primary radiation reaction. Inflammation as a protective body reaction to pathogens represents a self-organized system that commits support and limits the intensity of its manifestation. For this reason, the implementation of the radioprotective effect of radiomitigators, including immunogens, proinflammatory cytokines, steroid hormones, biogenic amines, and purine nucleosides and their synthetic and natural analogs, which stimulate native immunity, depends on its initial state and the severity of radiation injury of the body. The inverse negative relation in response to the action of proinflammatory cytokines, which is manifested as induction of the synthesis of anti-inflammatory cytokines and hematopoietic growth factors (primarily, granulocyte colony–stimulating factor), promotes the activation of myelopoiesis and their antiapoptotic action. The interaction of the immunogen effect and radiation stress depends on pharmacodynamics and features of the realization of the radioprotective properties of drugs. The implementation of the action of radiomitigators depends on the functioning of the antioxidant system of the body, because it can be exhausted under the influence of inflammation. In this case, postradiation oxidative toxemia induces injuries to vital parenchymatous organs. This is observed under the influence of proinflammatory cytokines at combined radiation injuries. All of the listed groups of radiomitigators have identical radioprotective activity (DRF = 1.2–1.3). The absence of expressed side effects, good tolerance of radiomitigators by humans, and the duration of their possible effective application after irradiation are the key indices for assessment of their prospects in radiation accidents.

This review presents the results of research concerning the role of zinc in neuronal membranes and synaptic processes. The development of views on zinc as an essential trace element is analyzed, from the demonstration of its catalytic, metabolic, and structural function to the elucidation of its regulatory role in intra- and inter-neuronal interactions. The body of information accumulated over recent decades on the significance of zinc for neuronal activity, in particular, for the regulation of excitation or inhibition, as well as for certain fine-tuned processes in the nerve cell membrane, is evaluated. The involvement of zinc in the functioning of the mediator brain systems, primarily, the glutamatergic system, is discussed. The available data on zinc vesiculation in neurons and its potential-dependent release into the synaptic cleft are analyzed. The processes in pre- or postsynaptic neuronal membranes involving zinc are described. Theories and hypotheses that expand views on zinc as a signal molecule are assessed. Attention is drawn to a number of controversial ideas and unsolved problems. For the specific case of the striatal nuclei, a hypothesis is developed about the involvement of vesicular zinc in the regulation of balance between the direct and indirect pathways, the two efferent systems of this subcortical formation, which is important for normal locomotor behavior and the prevention of neuromotor dysfunction.

Allelopathy is a kind of ecological competition between organisms that is widely spread in nature and exerts a significant effect on the functioning of biocenoses. In recent decades, significant results have been obtained on the isolation and identification of metabolites of plants and microorganisms with allelopathic activity and their role in soil ecosystems. The present review analyses data on allelopathic properties of plants and microorganisms, the main functions and modes of action of allelochemicals, and their stability in soil ecosystems. The role of allelopathic interactions in biocenoses and specific features of allelopathic activity under a changing environment and anthropogenic impact are discussed. The possibility of the use of allelopathy for the control of phytopathogens and future research directions are considered.