Resveratrol-Loaded Polymeric Nanoparticles: The Effects of D-α-Tocopheryl Polyethylene Glycol 1000 Succinate (TPGS) on Physicochemical and Biological Properties against Breast Cancer In Vitro and In Vivo

values of 0.12 µM, 0.73 µM, and 4.06 µM were found for the formulation without TPGS, with TPGS, and pure drug, respectively, indicating the potentiation of the cytotoxic effect of resveratrol when encapsulated. Flow cytometry and confocal microscopy tests indicated excellent cellular uptake dependent on the concentration of nanoparticles, with a significant difference between the two formulations, suggesting that TPGS may pose a problem in the endocytosis of nanoparticles. The in vivo study evaluating the antitumor activity of the nanoparticles confirmed the data obtained in the in vitro tests, demonstrating that the nanoparticle without TPGS significantly reduced tumor volume, tumor mass, maintained body weight, and improved survival in mice. Moreover, the biochemical evaluation evidenced possible hepatotoxicity for formulation with TPGS.