The Effect of Beta-lactoglobulin Nanocapsules Containing Astaxanthin and 5-fluorouracil on the Antioxidant Enzymes Activity of Superoxide Dismutase, Catalase and Glutathione Peroxidase in HCT116 Colorectal Cancer Cell Line

Background The use of nanoparticle drug delivery systems to enhance the therapeutic efficacy and reduce the side effects of anticancer drugs is taken into consideration. Astaxanthin (ATX) is a natural xanthophyll carotenoid with antioxidant, anti-inflammatory, and antiapoptotic properties used to prevent and treat some cancers. Objectives In the present study, the antioxidant effect of beta-lactoglobulin (& beta;-LG) nanocapsules containing ATX and 5-fluorouracil (5-FU; the first-line therapy for colorectal cancer) on the antioxidant enzymes activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in HCT116 colorectal cancer cell line was examined. Methods In this experimental study, HCT116 cells were treated with different treatments of encapsulation of ATX in & beta;-LG, encapsulation 5-FU in & beta;-LG, co-encapsulation of ATX and 5-FU in & beta;-LG, free ATX, free 5-FU, free ATX and free 5-FU, or & beta;-LG nanocapsules without drugs for 24, 48 and 72 hours. There is a control group in which HCT116 cells were not treated with any drug. Then, 50% inhibitory concentration (IC50) and cell viability were determined using an MTT assay. The antioxidant enzyme activity of SOD, CAT, and GPX was measured by a colorimetric method in HCT116 cells. Results Different treatments reduced the cell viability and increased apoptotic cells in a time-dependent manner, which was significant for beta-lactoglobulin nanocapsules treatment (p <0.05). It means receiving more 5-FU or ATX in the encapsulated form by HCT116 cells. The antioxidant enzyme activity of SOD, CAT, and GPX in HCT116 cells treated with beta-lactoglobulin nanocapsule treatment significantly increased compared to the control group (p <0.001). Moreover, the antioxidant activity of these enzymes in different treatments containing ATX (free or encapsulation) was significantly higher than in other treatments (p <0.05). The most increase in the activity of antioxidant enzymes is recorded in the treatment of nanocapsules containing ATX and 5-FU simultaneously. Conclusion Increased activity of antioxidant enzymes in addition to the induction of apoptosis in colorectal cancer cells by various treatments of beta-lactoglobulin nanocapsules indicates more effective drug administration in encapsulated form as well as synergistic thera[peutic effects of ATX and 5-FU. Moreover, the main increase in antioxidant enzyme activity may be related to ATX.