Crocus sativus L.: A comprehensive review

The effect of the extract of Crocus sativus on tracheal responsiveness and plasma levels of IL-4, IFN-γ, total NO and nitrite in ovalbumin sensitized guinea-pigs

ETHNOMEDICAL RELEVANCE: Anti-inflammatory, anti oxidant and effect of Crocus sativus (C. sativus) on Th1/Th2 balance were described previously.

AIM OF THE STUDY

The preventive effects of the extract of Crocus sativus on tracheal responsiveness and plasma levels of IL-4, IFN-γ, total NO and nitrite were examined on sensitized guinea pigs.

MATERIALS AND METHODS

Five groups of sensitized guinea pigs to ovalbumin (OVA), were given drinking water containing three concentrations of the extract of Crocus sativus, dexamethasone (S+D) or alone (group S). Tracheal responses (TR) of control animals (group C) and sensitized guinea pigs (n=6, for each group) to methacholine, OVA and the levels of IL-4, IFN-γ, total NO and nitrite in serum were examined.

RESULTS

The TR to both methacholine and OVA, the levels of serum IL-4, total NO and nitrite in S guinea pigs were significantly increased but that of IFN-γ and IFN-γ/IL-4 ratio (Th1/Th2 balance) were decreased compared to the controls (p<0.05 to p<0.001). In the treated animals with dexamethasone and all concentrations of the extract, TR to both methacholine and OVA, IL-4, total NO and nitrite were significantly decreased but IFN-γ and IFN-γ/IL-4 ratio increased compared to S group (p<0.05 to p<0.001). The effects of the highest concentration of the extract was greater than those of other concentrations and the effect of dexamethasone (p<0.05 to p<0.01).

CONCLUSIONS

These results not only showed a preventive effect of C. sativus extract on tracheal responses and serum levels of inflammatory mediators in sensitized guinea pigs but also showed increased Th1/Th2 balance.

Saffron (Crocus sativus L.) extract prevents and improves D-galactose and NaNO2 induced memory impairment in mice

This study was conducted to examine the effects of saffron extract on preventing D-galactose and NaNO2 induced memory impairment and improving learning and memory deficits in amnestic mice. In this study, the learning and memory functions in ovariectomized mice were examined by the one way passive and active avoidance tests. In active avoidance test, training in amnestic treated (AT) and amnestic prophylaxis (AP) groups, was improved so that there was a significant difference between them and the amnestic control (AC) group. In passive avoidance test, animal's step through latency, as an index for learning, in all test groups was significantly greater than control group. Total time spent in dark room (DS), which opposes the memory retention ability, in AC was significantly greater than AT group at 1 and 2 hours after full training, while there was not any significant difference between this index in AP and AT as compared with normal control (NC) group. Our findings indicate that saffron hydro-alcoholic extract prevents and improves amnesia induced by D-galactose and NaNO2 in mice.

Protective effect of crocin against reperfusion-induced cardiac arrhythmias in anaesthetized rats

The aim of the present study was to investigate the effects of crocin - a natural antioxidant derived from saffron - on cardiac reperfusion-induced arrhythmia and antioxidant systems such as catalase and superoxide dismutase (SOD) enzyme activities, glutathione (GSH) and malondialdehyde (MDA, as a marker of lipid peroxidation) levels. Rats in 4 experimental groups were administered crocin (20 mg/kg/day) or vehicle (i.p.) for 21 days with or without cardiac ischemia-reperfusion (IR). At the end of this period, hearts of anaesthetized animals in IR and "Cr + IR" groups were subjected to 10 min occlusion of the left anterior descending coronary artery and thereafter reperfused for 30 min. The results suggest that crocin is partially capable of suppressing reperfusion-induced arrhythmias. Compared to control group, ischemic-reperfusion injury significantly decreased SOD activity and GSH level and increased MDA level of heart muscle. "Cr + IR" group showed remarkably increased catalase activity in heart tissue (28.7 ± 6.6 vs. 23.6 ± 4.1 U/mg protein, P < 0.05) compared to the IR group. The level of cardiac tissue SOD activity in the "Cr + IR" group animals did not decline significantly compared to rats that were administered crocin alone with no ischemia. The results suggest a protective role of crocin on cardiac reperfusion arrhythmias which may at least partially be related to stability or even amplification of antioxidant systems. Crocin may potentially be useful for treatment or prevention of arrhythmias in patients with ischemic heart disease and this issue remains to be investigated in future clinical studies.