An edible green algae polysaccharide from <i>Caulerpa racemosa</i> var. <i>peltate</i> induced apoptosis of liver cancer cells Hepa1-6 by regulating glutathione metabolism

Algal polysaccharides are an essential active substance in food nutrition and even pharmaceutical activity research due to wide sources, low toxicity, and no side effects. In our previous research, we identified the chemical structure and studied the immunomodulatory mechanism of the polysaccharide from edible green algae <i>Caulerpa racemosa</i> var. <i>peltata</i> (CRVP). In this study, we further investigated the cytotoxicity and potential mechanism of CRVP against Hepa1-6 cells. Metabolomics analysis showed that CRVP might affect glutathione metabolism-related pathways. CRVP significantly up-regulated oxidized glutathione (GSSG) and down-regulated reduced glutathione (GSH) in Hepa1-6 cells, increasing the ratio of GSSG to GSH and intracellular reactive oxygen species. The potential anti-liver cancer mechanism is that CRVP may affect redox homeostasis and lead to apoptosis by inhibiting glutathione reductase or System Xc^–. Based on the known immunomodulatory mechanism of CRVP, this study can provide a material basis for adjuvant therapeutic nutritional agents with immune-enhancing anti-cancer activity.