Antitumoral Activity of Electrospray-Nanoencapsulated Tannic Acid on C6 and U87MG Glioblastoma Cell Lines

Glioblastoma (GBM) is a highly aggressive brain tumor with a poor prognosis. Polyphenols, known for their antioxidant and antitumor properties, may be potential therapeutic targets in GBM. Advances in nanomedicine have enabled the development of nanoparticles to improve the pharmacokinetics of polyphenols like tannic acid (TA). In this study, we investigated the therapeutic effects of 1.5% (w/w) TA-loaded zein-coated nanocapsules (NC-TA-ZN) on glioma cell lines (C6, U87MG). The cells were exposed to concentrations of 100, 125, 150 and 175 µg/mL for 72 h. NC-TA-ZN demonstrated cytotoxic effects, as evidenced by a significant reduction in cell viability (up to 47.10% in C6, 41.02% in U87MG) and cell biomass (up to 49.52% in C6, 66.65% in U87MG). It also reduced reactive oxygen species (up to 79.02% in C6, 60.77% in U87MG) and increased total sulfhydryl content (up to 97.37% in C6, 330.7% in U87MG). Additionally, it increased superoxide dismutase (up to 147.4% in C6, 341.4% in U87MG) and catalase activity (up to 287.6% in C6, 544.4% in U87MG). These results demonstrated the potential antioxidant effect of NC-TA-ZN. Lastly, NC-TA-ZN inhibited cell migration in C6 cells by 40% and 65% at 25 and 50 µg/mL, respectively. These results are significant given the relationship between oxidative stress and GBM development and progression, and suggest the potential of NC-TA-ZN as a therapeutic approach to GBM. Future studies will focus on understanding the mechanisms of cell death and the signaling pathways involved in the antiglioma effect elicited by nanoparticles of TA.