Crocin

This study explores the binding properties of two important constituents from Crocus sativus L (crocin and crocetin) with myosin, examining their influence on antioxidant capacity in myosin and a grilled meat model. And their impact on cytoprotective potential of myosin digestion products was also assessed in Caco-2 cells. Crocin and crocetin exhibited discernible binding affinity to myosin via static quenching, which induced conformational alterations that bolstered the antioxidant capacity of myosin, preventing peroxidation, which also corroborated in a grilled meat model. Crocin resulted in greater enhancement of antioxidant capacity and binding affinity, as confirmed by quantum chemical calculations. Molecular dynamics simulations revealed the stable binding of crocin to GLU:272, GLU:606, GLN:628, and PHE:417 residues of myosin. In addition, crocin substantially enhanced the protective efficacy of myosin digestion products against H₂O₂-induced damage in Caco-2 cells by upregulating superoxide dismutase and GSH-Px and simultaneously downregulating reactive oxygen species and malondialdehyde levels.

Combination therapy using inhibition of tumor cell escape and alteration of the tumor microenvironment offers a new strategy for cancer treatment. This study aimed to develop an extracellular vesicle (EV) carrier that regulates tumor cells and the tumor microenvironment to achieve efficient tumor immunotherapy. The ligand modified on carriers targets the immune checkpoint CD47 protein, blocking tumor cell escape. This ligand is cleaved by the MMP2 enzyme and assembles into nanofibers, extending the retention time in the tumor. The carriers target the CD206 protein, enabling efficient uptake by M2 macrophages. Carriers with a high density of ligands (anti-CD206) exhibit strong receptorligand interactions with tumor cells. Due to their high rigidity, these EVs have difficulty deforming during the transmembrane process, reducing resistance and resulting in low uptake efficiency by M2 cells. The optimal uptake efficiency by M2 macrophages is achieved when the mass ratio of ligand to EVs is 1:25. Crocin loaded in EVs facilitates the polarization of M2 macrophages into M1 cells, which can phagocytize tumor cells. This study reveals a potential strategy for using extracellular vesicles in tumor treatment.