Study the Synergistic Effect of Combination Therapy Containing Temozolomide and N-Acetylcysteine Loaded Polymeric Micelles in Cancer Treatment

Abstract

Purpose: The aim of this study was to develop TMZ-NAC loaded polymeric micelles (TNPM), evaluate them in vitro, and study the synergistic effect between Temozolomide (TMZ) and N-acetylcysteine (NAC) on the human glioblastoma multiforme A172 cell line (HGM-A172). Methods: Six (TNPM) formulations (F1 to F6) were fabricated by pluronic p-123 (P123) and pluronic p-188 (P188) at different molar percentages using a modified thin-film hydration method. The formula F5 provided the highest percentage of drug loading for TMZ and NAC. Thus, different ratios of the two drugs were loaded in polymeric micelles (PM) with molar percentage (80:20) of P123:P188 to form eight TNPM formulations (L1 to L8) that were evaluated for cytotoxic effect against (HGM-A172). Results: TNPM formulations (L2, L3 and L4) provided the lowest IC50 (31.5±0.38 mg/ml, 19.94±0.15 mg/ml and 18.3±0.21 mg/ml, respectively). Furthermore, Characterization of the selected (L2 and L4) was done. Moreover, the formula (L4) was selected according to the previous characterization for in vitro release studies, cell cycle analysis, cell apoptosis and cellular uptake. The L4 showed an average particle size 25.39±10.31 nm and zeta potential -24.5±4.8 mV. The DSC and FT-IR analysis confirmed the encapsulation of both drugs within PM. TNPM (L4) provided a 1.783-fold increase in the dissolution efficiency (%) of TMZ, compared to pure TMZ. The cellular uptake efficiency after 24 h was 30.48 and 15 folds higher than the free TMZ and free NAC, respectively. Conclusion: The combination index calculation, cell cycle analysis and cell apoptosis confirmed the cytotoxic synergistic effect between TMZ and NAC in L4 against (HGM-A172).

Keywords: Glioblastoma, N-acetylcysteine, Polymeric micelle, Synergism, Temozolomide