Background: It is well known that extracellular and intracellular pH changes have cytotoxic effects on astrocytes and neurons. In the present study, we aimed to evaluate the cytotoxic effects of acidosis on astrocyte cultures by measuring cell death and oxidative stress parameters. We also investigated the protective effects of ascorbic acid and gluthatione as antioxidants against toxicity due to pH changes in the cultures.
Materials and Methods: Primary astrocyte cultures were prepared from 1-2 day old neonatal rats. Astrocytes were incubated in media with or without pH 5,5 ± 0,1 for 2 h and treated with ascorbic acid (AA, 1 mM) and glutathione (GSH, 1 mM). The effects of acidosis and antioxidants were assessed by measuring lactate dehydrogenase (LDH), superoxide dismutase (SOD) and catalase activities and nitrite levels in the cultures.
Results: LDH activity, nitrite levels and antioxidant enzyme activities were found significantly elevated in the acidosis group than the control (p< 0.0005). Treatment of the astrocytes with GSH decreased cell death, nitrite levels and antioxidant enzyme activities compare to the acidosis group. Although the treatment of the cultures with AA lowered antioxidant enzyme activities and ntirite levels, there was no protective effect on astrocyte viability.
Conclusions: Our results demonstrated that decreased of pH levels may effect astrocyte viability and antioxidant enzyme activities. Treatment of the astrocytes with GSH may protect them from cytotoxicity and oxidative stress. Overall, these results support that acidosis and oxidative stress closely interact with each other and may trigger cell damage in brain.