Turkish coffee suppresses the progression of C6 glioma cells via the activation of apoptosis

Abstract

Glioma is the most invasive form of brain tumor and usually results in death within months of diagnosis. C6 glioma cells are frequently used in glioblastoma multiform studies because they are cells with different malignant glioblastoma features. Coffee is one of the most popular beverages consumed in large quantities. Recent research has shown the functional and protective potential properties of coffee as well as its stimulatory effect. Coffee blending and grinding processes change the antioxidant composition of coffee. The main characteristic separating Turkish Coffee (TC), which is formed from freshly roasted pulverized coffee beans, from the other coffee types is the brewing method. Our aim in this study is to investigate the antioxidant and apoptotic effects of TC prepared with the traditional method on C6 glioma cells, which are glial cells derived from rat brain with glioma. Cell viability in C6 glioma cells treated with TC at different concentrations (0-8000 mu g/ml) was analyzed by the MTT method. According to MTT results, three doses (10000, 15000, and 20000 mu g/ml) of TC were applied to the cells and the untreated cells were considered the control. Total oxidant and antioxidant statuses (TOS, TAS) and oxidative stress markers were determined. Caspase-3, caspase-8, and caspase-9 mRNA expressions were detected by using quantitative real-time PCR. It was determined that the application of TC at concentrations of 4000 mu g/ml and above to C6 glioma cells inhibited cell proliferation depending on the concentration. Caspase 3, caspase-8, and caspase-9 mRNA expression levels increased in C6 glioma cells treated with TC at concentrations of 10000 and 15000 mu g/ml as compared to control cells. TAS and TOS levels were unchanged, while protein carbonyl levels increased in TC treated C6 glioma cells compared to the control group. These findings suggested that TC may induce apoptosis by changing caspases expressions and inducing protein oxidation. Thus, it can be thought that TC may prevent the proliferation of C6 glioma cells.