Tag Archives: cell viability

Biological and analytical studies of peritoneal dialysis solutions

N. Hudz1, L. Kobylinska1, N. Dmytrukha2, R. Korytniuk3, P.P. Wieczorek4

1Danylo Halytsky Lviv National Medical University, Ukraine;
e-mail: natali_gudz@ukr.net;
2SI “Institute for Occupational Health of National Academy of Medical Sciences of Ukraine”, Kyiv;
3Shupyk National Medical Academy of Postgraduate Education, Kyiv, Ukraine;
4University of Opole, Poland

The purpose of our work was to conduct biological and analytical studies of the peritoneal dialysis (PD) solutions containing glucose and sodium lactate and establish correlations between cell viability of the Vero cell line and values of analytical indexes of the tested solutions. The results of this study confirm the cytotoxicity of the PD solutions even compared with the isotonic solution of sodium chloride, which may be due to the low pH of the solutions, presence of glucose degradation products (GDPs) and high osmolarity of the solutions, and unphysiological concentrations of glucose and sodium lactate. However, it is not yet known what factors or their combination and to what extent cause the cytotoxicity of PD solutions. In the neutral red (NR) test the weak, almost middle (r = -0.496 and 0.498, respectively) and unexpected correlations were found between reduced viability of monkey kidney cells and increased pH of the PD solutions and between increased cell viability and increased absorbance at 228 nm of the tested PD solutions. These two correlations can be explained by a strong correlation (r = -0.948) between a decrease in pH and an increase in the solution absorbance at 228 nm. The opposite effect was observed in the MTT test. The weak, but expected correlations (r = 0.32 and -0.202, respectively) were found between increased cell viability and  increased pH in the PD solutions and between decreased cell viability and increased absorbance at 228 nm of the tested PD solutions. The middle and weak correlations (r = 0.56 and 0.29, respectively) were detected between increased cell viability and increased lactate concentration in the NR test and MTT test. The data of these correlations can be partially explained by the fact that a correlation with a coefficient r = -0.34 was found between decreased pH in the solutions and increased lactate concentration. The very weak correlations (0.138 and 0.196, respectively) were found between increased cell viability and increased glucose concentration in the NR test and MTT test. These experimental data indicate that pH is the dominating factor, which determines almost all of the established correlations. However, the character of the correlations is quite different: the higher the pH, the greater was the cell viability in the MTT test, and conversely, the higher the pH, the lower was the cell viability in the NR test. Secondly, the unexpected correlation coefficient was determined as -0.473 between decreased cell viability in the MTT test and increased cell viability in the NR test. Moreover, this phenomenon indicates that the mitochondrial enzyme succinate dehydrogenase is more vulnerable to the action of PD solutions than membrane permeability. Finally, we conclude that the NR test is not suitable for comparative studies of PD solutions which differ in pH, as it is pH dependent and does not enable the comparison of plausible cell viability.

Nicotinamide influence on pancreatic cells viability

Т. М. Kuchmerovska1, G. V. Donchenko1, T. M. Tychonenko1, M. M. Guzyk1,
R. V. Stavniichuk1, L. V. Yanitska2, S. P. Stepanenko1, А. P. Klimenko1

1Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kyiv;
2Bogomolets National Medical University, Kyiv, Ukraine;
e-mail: kuch@biochem.kiev.ua

The study was undertaken to investigate the modulating effect of nicotinamide (NAm) in different concentrations and under different glucose concentrations on the viability and oxidative stress induced by streptozotocin (STZ, 5 mmol/l) and hydrogen peroxide (H2O2, 100 µmol/l) on isolated rat pancreatic cells of the Langerhans islets in vitro. Cell viability did not depend on the concentration of glucose in the range of 5-20 mmol/l, and in subsequent studies we used glucose in concentration of 10 mmol/l to protect cells against its hypo- and hyperglycemic action. Cytoprotective effect of NAm in concentrations from 5 to 20 mmol/l on cells survival was the same. It was found that the destructive action of STZ and H2O2 during 24 hours on isolated cells of the pancreas resulted in the significant cell death. It was revealed that NAm in concentration of 5 mmol/l not only had cytoprotective effects against STZ and H2O2 but also partially reduced the level of oxidative stress in the investigated cells induced by these compounds. High concentration of NAm, 35 mmol/l, causes cytotoxic effect on the viability of pancreatic islet cells and increase of oxidative stress induced by STZ and H2O2.
Most likely these effects could be associated with direct modulatory action of NAm on important effector mechanisms involved in cell death, including PARP-dependent processes, or/and indirectly, through metabolic and antioxidant effects of the compound.

Generation of active oxygen forms in rat tymocytes under action of hydrogen peroxide and fullerene C(60)

S. M. Grebinyk, I. I. Grynyuk, S. V. Prylutska, O. P. Matyshevska

Taras Shevchenko Kyiv National University, Ukraine;
e-mail: grebnik_z@yahoo.com

The dynamics of active oxygen forms (AOF) generation in rat thymocytes 50 min after treatment with 0.1 and 0.5 mM H2O2 was estimated with the use of fluorescent probe DCFDA. Both enhanced AOF generation, which was dependent on H2O2 concentration, and glutathione peroxidase and superoxide dismutase activation, followed by a decrease of thymocytes viability were demonstrated.
Preincubation of cells with 10-5 M fullerene C60 was shown not only to prevent H2O2 – induced AOF generation but to increase viability of H2O2-treated thymocytes at more prolonged time period. The data obtained indicate to fullerene C60 ability to prevent oxidative stress in thymocytes.