Aim: To evaluate the viability of leukemic cells sensitive (L1210S) and resistant (L1210R) to cisplatin, ROS production and free cytosolic Ca2+ concentration under treatment with cisplatin or its combination with photoexcited fullerene C60. Methods: Cell viability was assessed by the MTT reduction assay. Light-emitting diode lamp (2.45 J/сm2) was used for photoexcitation of intracellular accumulated fullerene C60. Free cytosolic calcium concentration ([Ca2+]i) and ROS production in cells were estimated with the use of fluorescent probes Indo-1 and 2′,7′-dichlorodihydrofluorescein diacetate (DCF-DA), respectively. Results: It is shown that viability of L1210R cells wasn’t changed under treatment with cisplatin in concentration range 0.1–10 μg/ml. 50% and 30% decrease of L1210S cells were observed after 24 h of incubation with cisplatin at concentrations 5 and 1 μg/ml, respectively. Intensification of extranuclear cytotoxic effects (ROS production and [Ca2+]i increase) after treatment with 1 μg/ml was detected in L1210S, but not in L1210R cells. The most strongly pronounced increase of ROS production and [Ca2+]i in both L1210 cell lines was revealed in dynamics after combined treatment with cisplatin (1 μg/ml) and photoexcited fullerene C60 (10–5 M) and was followed by decreased viability of not only L1210S, but of L1210R cells as well.. Conclusion: Combined treatment with photoexcited C60 and cisplatin allowed to decrease effective concentration of cisplatin against parental L1210 cells and to increase sensibility of resistant cells to the drug.

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The increasing of Cftr, Slc9a3 and the decreasing of Snn1b gene's expression in rat duodenal villus and crypt epithelial cells against the background of intensification of free radical formation upon gastric hypoacidic conditions were shown. The level of above mentioned gene's expression both in villus and crypt epitheliocytes approached to the control value upon the treatment of hypoacidic rats with multiprobiotic Symbiter.

Importance of dedicated web servers and specialized software for simulations of protein-protein interactions is well established. The purpose of our study was to examine the protein-protein interaction that occurred under physiological and stress conditions between peroxiredoxin II and the creatine kinase brain-type using proteindocking server ClusPro 2.0. To predict the particular site of amino acid docking, computer software analyzes various protein conformations and chooses the most profitable energy state, therefore selecting a number of possible combinations that would fit the correct profile. By co-immunoprecipitation assay, we demonstrated that two molecules Prx II and CKBB have interacted with further attenuation of this specific binding by pretreatment with selected stress factors. In previous study, we showed that the enzymatic activity of CKBB was recovered by different concentration ratios of Prx II. The specific binding models were generated by ClusPro 2.0 protein docking server and studied using PyMol software. It was shown that a number of amino acid residues including Lys 11, Arg 13, Ala 204, Arg 209for creatine kinase, and Asp 181, Glu 192, Lys 196, Glu 162, Gln 163 for Prx II have participated in the complex formation throughout the first ten conformations.