INPACT OF LAPONITE ON ENZYME ACTIVITY AND REDOX STATE OF THE TUMOR AND ORGANS OF THE DETOXIFICATION SYSTEM OF MICE WITH EhRLICH CARCINOMA

Abstract

Summary. Laponite (Lap) is a synthetic clay mineral represented by disk-shaped nanoplatelets. The Lap (native or acid-activated) can be used for encapsulation of medical compounds, in particular anticancer drugs. Aim: to study the levels of the rate of superoxide radical (SR) generation, the activity of ribonucleases (RNases), gelatinases and ornithine decarboxylase (ODK) in tumor cells, liver and kidneys of intact mice and mice with Ehrlich carcinoma under the influence of Lap. Objects and methods: the purified gel-forming native Lap of the XLG class with the empirical formula Si8Mg5.45Li0.4H4O24Na0.7 was used. Acid activation of Lap (aLap samples) was done using sulfuric acid. The laboratory experiments were performed using outbred mice with transplanted Ehrlich carcinoma in ascites and solid forms. Determination of the rate of generation of SR was carried out by the method of electron paramagnetic resonance, RNases and matrix metalloproteinases activities were determined zymography in polyacrylamide gel, ODC activity was determined spectrophotometrically, statistical analysis of the results was performed using Student’s t-test. Results: the data on the rate of the superoxide generation and the activity of gelatinases in the liver tissue, the tumor tissue and the ascites fluid Ehrlich carcinoma were compared. The introducing of native Lap resulted in noticeable decrease in the rate of the superoxide generation in the liver tissue by 1.7 times as compared with the control group of mice, and in the ascites fluid by 1.5 times as compared with the mice group without Lap. Moreover, introducing of native Lap resulted in the decrease of the gelatinases activity by 2.4 times in the ascites fluid and 1.9 times in the solid Ehrlich carcinoma tissue. The less significant effects were observed for samples with incorporated aLap. No significant difference was found between the indicators of RNase and ODC activities under the influence of native Lap and aLap in intact and tumour-bearing mice. Conclusion: in a model experiment on outbred mice with Ehrlich carcinoma, it was determined that native Lap and aLap do not significantly affect the indicators of the redox state, the activity of RNases, gelatinases and ODC in tumor cells, liver and kidneys. It indicates the safety of using of these nanoplatelets for assistance of anticancer drug delivery.