Effect of α-tocopheryl succinate on the molecular damage induced by indomethacin in C6 glioma cells

Abstract

Indomethacin is a member of the non-steroidal anti-inflammatory drug (NSAID) class, which has great potential for use in the treatment of glioma. However, it induces the generation of reactive oxygen species (ROS) and causes molecular damage while inducing its effects. Vitamin E is widely used in the complementary therapy of cancers. The main goal of the present study was to investigate the effects of α-tocopheryl succinate (α-TOS) against the oxidative damage induced by indomethacin in C6 glioma cells. Cells were treated with 10 μM α-TOS alone or in combination with 200 μM indomethacin for two days. The intracellular ROS level, molecular damage as revealed by lipid peroxidation and protein carbonyl formation, and the COX activity in C6 glioma cells were measured. Treatment of the cells with α-TOS and indomethacin, alone or in combination, caused the levels of ROS generation and protein damage to increase, but protected against lipid peroxidation and reduced COX activity.

Keywords: C6 Glioma; indomethacin; intracellular ROS level; protein carbonyls; α-tocopheryl succinate.

Figure 1

Effect of (A) α-TOS, (B) IND and (C) α-TOS in combination with 200 μM IND on cell survival in the C6 glioma cell line. Experiments were performed in triplicate. The vertical bars on the points on the graph show standard deviation values. The consistency between groups was determined by one-way analysis of variance (P<0.001; R², 0.996). α-TOS, α-tocopheryl succinate; IND, indomethacin.

Figure 2

Oxidative stress parameters in C6 glioma cells. (A) ROS levels and (B) lipid peroxidation (TBARS levels). Experiments were performed in triplicate. The vertical bars above the columns show standard deviation values. The consistency between groups was determined by one-way analysis of variance ^*P<0.05, ^***P<0.001 compared with the control group. ROS, reactive oxygen species; TBARS, thiobarbituric acid reactive substances; α-TOS, α-tocopheryl succinate; IND, indomethacin; MDA, malondialdehyde.

Figure 3

(A) Protein profiles in a denaturated gel stained with Coomassie blue. (B) Carbonylated proteins on a X-ray film. Protein mixture containing lysozyme (19 kDa), β-lactoglobulin (26 kDa), carbonic anhydrase (34 kDa), ovalbumin (48 kDa), bovine serum albumin (85 kDa) and β-galactosidase (117 kDa) was used as a marker. α-TOS, α-tocopheryl succinate; IND, indomethacin.