Nanohydrogel of Curcumin/Berberine Co-Crystals Induces Apoptosis via Dual Covalent/Noncovalent Inhibition of Caspases in Endometrial Cancer Cell Lines: The Synergy Between Pharmacokinetics and Pharmacodynamics

Abstract

Endometrial cancer remains a significant therapeutic challenge due to drug resistance and heterogeneity. This study leverages the synergistic potential of curcumin (CUR) and berberine (BBR) co-crystals encapsulated in a nanohydrogel to address these challenges through a pharmacokinetically and pharmacodynamically targeted therapeutic strategy. The nanohydrogel formulation significantly improves the solubility, stability, and bioavailability of CUR/BBR co-crystals, optimizing their therapeutic delivery and sustained release under physiological and tumor microenvironment conditions. On the other hand, the dual inhibitory mechanism of CUR and BBR, with CUR covalently binding to the active site of caspase-3 and BBR non-covalently targeting the allosteric site, achieves enhanced apoptotic activity by disrupting both the catalytic and conformational functions of caspase-3. In vitro cytotoxicity assays demonstrate remarkable efficacy of the CUR/BBR nanohydrogel, achieving an IC50 of 12.36 μg/mL against HEC-59 endometrial cancer cells, significantly outperforming the individual components and the standard drug Camptothecin (IC50: 17.27 μg/mL). Caspase-3/7 assays confirm enhanced apoptosis induction for the nanohydrogel formulation compared to co-crystals alone and Camptothecin. Molecular dynamics simulations and binding free energy analyses further validate the synergistic interaction of CUR and BBR in their dual binding mode. This study introduces a novel therapeutic approach by enhancing drug delivery and dual targeting mechanisms, demonstrating the potential of CUR-BBR nanohydrogel as a robust therapy for EC. This strategy offers a promising platform for addressing drug resistance and improving outcomes in endometrial cancer therapy.