Immunoregulatory and anti-inflammatory properties of Crocus sativus (Saffron) and its main active constituents: A review

The medicinal uses of saffron, the dried stigmas of Crocus sativus L., have very long history in food coloring agent, and flavoring agent as well as traditional medicine for the treatment of several diseases. Crocus sativus is rich in carotenoids that affect immunity. This review summarizes the putative immunoregulatory effects of saffron and its active its derivatives including crocin, crocetin and safranal. In modern studies, its active constituents including protective effects, anti-inflammatory activities and molecular mechanisms of saffron on thimmune system have been demonstrated. Furthermore, the beneficial effects of saffron on inhibition of serum levels nuclear transcription factor κB (NF-κB) p65 unit, tumor necrosis factor alpha (TNF-α), interferon gamma (IFN-γ) and some interleukin (IL) such as IL-1β, IL-6, IL-12, IL-17A were reported. Furthermore, saffron has been known as the antagonist of NF-κB and the agonist of peroxisome proliferator-activated receptor gamma (PPAR-γ). In addition, saffron down-regulates the key pro-inflammatory enzymes such as myeloperoxidase (MPO), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), phospholipase A2, and prostanoids. This review summarizes the protective roles of C. sativus and its constituents against the pathogenesis of immune diseases and understanding a better management of these problems. Taken together, the main bioactive constituents of saffron may have health-promoting with important benefits in immunerelated disorders. Finally, our study indicates that these bioactive constituents can affect both cellular and humoral immunity functions.