Objective: Saffron Crocus sativus L. (Iridaceae) is known for anticancer properties. However, limited effort has been made to correlate these effects to the active ingredients of saffron. In the present study, cytotoxic effects of crocin, the major coloring compound in saffron, and its nanoliposomal form for better cellular delivery are investigated.
Methods: HeLa and MCF-7 cells were cultured and exposed to crocin (1, 2, and 4 mM) and liposomal crocin (0.5 and 1 mM). The 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was performed to assess cytotoxicity. Apoptotic cells were determined using propidium iodide (PI) staining of DNA fragmentation by flow cytometry.
Results: MTT assay revealed a remarkable and concentration-dependent cytotoxic effect of crocin on HeLa and MCF-7 cells in comparison with non-malignant cell line (L929). Crocin liposomal forms (IC(50) values after 48 h: 0.61, 0.64, and 1.2 mM) showed enhanced cytotoxic effect compared with the crocin (IC(50) after 48 h: 1.603 mM) in HeLa cells. Crocin and its liposomal form induced a sub-G1 peak in flow cytometry histogram of treated cells indicating apoptosis is involved in this toxicity. Liposomal encapsulation enhances apoptogenic effects of crocin on cancerous cells.
Conclusion: It might be concluded that crocin and its liposomes could cause cell death in HeLa and MCF-7 cells, in which liposomal encapsulation improved cytotoxic effects. They could be also considered as a promising chemotherapeutic agent in cancer treatment in future.