The most important aspect of up-to-date nanomedicine is the use of specific nanocarriers that can deliver drugs to the pathological tissues and certain organs to ensure more effective therapy. The nanocarriers are thought to be extremely promising in the modern nanopharmacology, whereas they possess a range of specific physical, chemical and biological properties that ensure their biocompatibility, possibility of additional functionalization of special bioelements needed to deliver pharmaceutical preparations into the body. It has been found that the dosage forms in which the active ingredient is conjugated to a polymeric carrier have lower toxicity, improve the pharmacokinetic parameters and have higher therapeutic efficacy. Therefore, one of the main tasks of modern bionanotechnology is the development of the safe nano-sized carriers of a certain size, low toxicity, physical stability in the blood, compatibility with metabolites of the body, regulated influence on the damages, abilities to deliver the drugs directly to the target. Mostly, polyethylene glycol (PEG) is used for this purpose. It increases the solubility of hydrophobic drugs, prolongs the circulation time, minimizes the nonspecific absorption, specifically targeting at the tumor and having the tendency to accumulate drugs in the tissue.
It is believed that a mechanism of influence of polymers on the living organisms means violation to a functional state of the plasma membranes, metabolic processes, water-salt balance of the cell, mediated interaction with membrane enzymes and receptors.
It has been shown that the activity of Na+/K+-ATPase, which plays a key role in the maintenance of intracellular ion homeostasis, osmotic cell balance, transmembrane cell potential, apoptosis regulation, cell proliferation and differentiation is changing under the influence of hormones, growth factors and stress. Therefore, from a biophysical approach, the research of the influence of polymers on the basis of PEG on the activity of membrane enzymes of embryo cells is relevant and promising.
The data of the enzymatic activity of Na+, K+-pump of cold-blooded embryo modification under the influence of the newly synthesized nanoparticles of polyethylene glycol nature have been obtained.
Na+/K+-АТPase activity has been calculated as a difference between the amount of inorganic phosphate released in the conditions of presence and absence of membrane fragments in the incubation medium, including the loss of endogenous phosphorus Pi in the membrane preparation, expressed in μmoles Pi per minutes per milligram of protein. The amount of endogenous phosphorus has been identified by the modified Fiske-Subbarow method, the quantitation of protein in the membrane preparation has been determined by the Lowry method.
The results have shown that the presence of a polymer produces the decrease of the enzyme activity, nevertheless it maintains the dome-shaped trend of pH depending on the activity under the normal conditions and not taking into account a stage of development. A level of the enzymatic hydrolysis of ATP Na+, K+-ATPase in the presence of a polymer has been 61, 37 and 32 % instages, that respectively has meant 6th and 10th blastomeres division. Heterogeneity of the cell membrane during the early embryogenesis and different affinity of a polymer and membrane lipids in the consequence of the pH changes can determine a stage of alternating of the enzymatic hydrolysis of ATP by the investigated enzyme, which varies during its developing.
Article recieved: 30.04.2018
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