New Highlights in the Regulation of Cells Proliferation

Background: Rate-limiting enzymes of purine and pyrimidine catabolisms might possess with the abilities of key regulators of cells proliferation. In our previous work we have shown that allopurinol, classical inhibitor of Xanthine Oxidase (XO; EC. 1.1.3.22), is capable of regulating purine catabolism in the liver tissue. Our current results prove that evidence for the brain tissue after utility of other biomolecules – pyridoxine, epinephrine. Methods: Cultivation of (E90) human brain cells was performed by the modified method of Mattson (1990). Specific activity of XO was delineated by the utility of the method measuring formation of the uric acid. Quantification of the cells stained by the Trypan Blue allowed determination of the healthy cells yield. Purification of the XO was performed based on the routine biochemical procedures with further utility of preparative electrophoresis and RP-HPLC. Results and conclusion: The newly developed methods for purification of XO served as a basis for delineation of Ki (0.0076 mM), Vmax (0.0279) values for the pyridoxine as an inhibitor of XO. We studied interaction of XO and pyridoxine in pyridoxine depleted, theophylline treated rats. Also, we estimated the tight interaction between the synthesis of epinephrine and XO activity, which greatly influences the processes of cells proliferation and death during in vitro studies.