Iron(III)-Tannic Molecular Nanoparticles Enhance Autophagy effect and T(1) MRI Contrast in Liver Cell Lines

Herein, a new molecular nanoparticle based on iron(III)-tannic complexes (Fe–TA NPs) is presented. The Fe–TA NPs were simply obtained by mixing the precursors in a buffered solution at room temperature, and they exhibited good physicochemical properties with capability of inducing autophagy in both hepatocellular carcinoma cells (HepG2.2.15) and normal rat hepatocytes (AML12). The Fe–TA NPs were found to induce HepG2.2.15 cell death via autophagic cell death but have no effect on cell viability in AML12 cells. This is possibly due to the much higher uptake of the Fe–TA NPs by the HepG2.2.15 cells via the receptor-mediated endocytosis pathway. As a consequence, enhancement of the T(1) MRI contrast was clearly observed in the HepG2.2.15 cells. The results demonstrate that the Fe–TA NPs could provide a new strategy combining diagnostic and therapeutic functions for hepatocellular carcinoma. Additionally, because of their autophagy-inducing properties, they can be applied as autophagy enhancers for prevention and treatment of other diseases.