The Effect of Water Soluble Carotenoids of Saffron on Cell-Mediated Immunity in BALB/c Mice

Saffron (thread-like reddish colored stigmas of Crocus sativus L. flowers) was used in traditional medicine for cancers and infectious diseases. Recently, anti-tumor, cytotoxic, anti-mutagenesis and antioxidant activities of saffron metabolites, especially its carotenoids (crocins and crocetin), have been reported.

Since the saffron is used as a spice for food flavoring and coloring and it is also used as a traditional herbal drug, in this study the effect of saffron water soluble carotenoids was assessed on cell mediated immune response in a BALB/c mice model.

Crocus sativus L. stigmas were collected during flowering season and air dried at 25 ° C in the dark. First, dried stigmas (100 mg) were successively and exhaustively extracted with light petroleum and diethyl ether in a Soxhlet extractor in the dark to remove non-glycosidic carotenoids, lipids, picrocrocin and odor compounds. Then, for separation of water soluble carotenoids, stigma sample was extracted with distilled water in a 10-mL ground-glass stopper tube in a boiling water bath for 20 min. Then, the suspension was centrifuged at 3000 x g and at 10 ° C for 20 min to separate the vegetable tissue residue. The different doses of extract were injected to six groups of four BALB/c mice. The delayed-type hypersensivity (DTH) response and cell viability (MTT test) were performed to determine cell mediated immunity.

Splenocytes that were extracted from treated mice with 10 or 20 mg/kg of water soluble carotenoids of saffron have shown a significant (p<0.05) decrease in cellular viability at the absence of mitogene stimulation in vitro, and a significant decrease was observed in splenocytes cellular viability of mice that have been treated with 20 mg/kg of water soluble carotenoids in the presence of mitogene. In this study, all used doses did not have any significant effect on DTH response (p<0.05).

Results of the present study showed that water soluble carotenoids of saffron have a dose-dependent effect on cell mediated immune response. Further studies on other mechanisms such as cytokine patterns are needed for exact evaluation of immunomodulatory effects of saffron carotenoids.