Evaluation of antioxidant activities of bioactive compounds and various extracts obtained from saffron (Crocus sativus L.): a review

Efficacy of crocin and safranal as protective agents against genotoxic stress induced by gamma radiation, urethane and procarbazine in mice

Crocin (CRO) and safranal (SAF) are bioactive constituents of saffron (dried stigma of Crocus sativus flower), an expensive spice with medicinal properties. Aqueous extract of saffron is known for its antigenotoxic effect against environmental genotoxins/carcinogens. However, there is need to identify saffron constituents responsible for this antigenotoxic effect. The aim of our investigation was to ascertain the role of CRO and SAF as inhibitors of in vivo genotoxic stress. For this purpose, Swiss albino mice were pretreated with CRO (50-mg/kg body weight (bw))/SAF (0.025- and 0.25-ml/kg bw) by gavage for 2 days. Thereafter, the pretreated mice were exposed to the genotoxic agents: (1) gamma radiation (GR; 2 Gy), (2) urethane (URE; 800 mg/kg) and (3) procarbazine (PCB; 60 mg/kg). In addition, CRO (50 mg/kg) was co-administered with the nitrosation reaction mixture of methylurea (MU; 300-mg/kg bw) + sodium nitrite (15 mg/kg) which can form N-nitroso-N-MU in the stomach. Genotoxic damage was measured by performing the bone marrow micronucleus test. Results obtained demonstrated significant reductions in the incidence of micronucleated polychromatic erythrocytes in the bone marrow of mice pretreated with CRO/SAF before exposure to the above DNA damaging agents, GR, URE and PCB. Co-administration of CRO with the nitrosation reaction mixture led to significant decrease in genotoxicity when compared to nitrosation reaction mixture alone. Histopathological studies revealed that these saffron constituents reduced testicular cell damage induced by the test genotoxins. The cell-free DNA-nicking assay using pBR322 DNA showed significant protective effects of CRO against hydroxyl radical-induced strand breaks.

The Efficacy of Crocin of Saffron (Crocus sativus L.) on the Components of Metabolic Syndrome: A Randomized Controlled Clinical Trial

Objective:

Metabolic syndrome is a set of cardiac risk factors with increased risk of chronic diseases. The aim of this study is to evaluate the efficacy of crocin of saffron on metabolic syndrome.

Methods:

This double-blind, randomized clinical trial was conducted on metabolic syndrome patients who were randomly assigned to crocin of saffron or control (placebo) groups. The intervention group received 100 mg/day crocin tablets (a constituent of saffron) for 6 weeks. Then, the changes in metabolic syndrome component were compared between two groups. The trial was registered in the Iranian Registry of Clinical Trials. Data were entered to SPSS 15. Chi-square, Fisher's exact, paired t-test, and independent t-test were used to analyze data. P < 0.05 was defined as statistical significant level.

Findings:

Totally, 48 patients included in the trial (24 intervention and 24 placebo participants). There were significant reductions from baseline measurements in the levels of total cholesterol (P < 0.001) and triglyceride (P = 0.003) after the 6-week crocin administration. However, this decrease in lipid profile was not significant when compared with placebo group. There was no significant change in other laboratory values, blood pressure, and anthropometric measures.

Conclusion:

The present study indicated that the dose of about 100 mg crocin of saffron was well tolerated and has no complication for 6 weeks of oral administration. However, the dosage used in our study had no effect on metabolic syndrome. Further studies are required to assess this effect with the higher dosages of crocin as well as long time effects of its administration on metabolic syndrome patients.

Widespread brain transcriptome alterations underlie the neuroprotective actions of dietary saffron

Dietary saffron has shown promise as a neuroprotective intervention in clinical trials of retinal degeneration and dementia and in animal models of multiple CNS disorders, including Parkinson's disease. This therapeutic potential makes it important to define the relationship between dose and protection and the mechanisms involved. To explore these two issues, mice were pre-conditioned by providing an aqueous extract of saffron (0.01% w/v) as their drinking water for 2, 5 or 10 days before administration of the parkinsonian neurotoxin MPTP (50 mg/kg). Five days of saffron pre-conditioning provided the greatest benefit against MPTP-induced neuropathology, significantly mitigating both loss of functional dopaminergic cells in the substantia nigra pars compacta (p < 0.01) and abnormal neuronal activity in the caudate-putamen complex (p < 0.0001). RNA microarray analysis of the brain transcriptome of mice pre-conditioned with saffron for 5 days revealed differential expression of 424 genes. Bioinformatics analysis identified enrichment of molecular pathways (e.g. adherens junction, TNFR1 and Fas signaling) and expression changes in candidate genes (Cyr61, Gpx8, Ndufs4, and Nos1ap) with known neuroprotective actions. The apparent biphasic nature of the dose-response relationship between saffron and measures of neuroprotection, together with the stress-inducible nature of many of the up-regulated genes and pathways, lend credence to the idea that saffron, like various other phytochemicals, is a hormetic stimulus, with functions beyond its strong antioxidant capacity. These findings provide impetus for a more comprehensive evaluation of saffron as a neuroprotective intervention.

Crocin treatment prevents doxorubicin-induced cardiotoxicity in rats

Doxorubicin (DOX)-induced cardiotoxicity is well-known as a serious complication of chemotherapy in patients with cancer. It is unknown whether crocin (CRO), main component of Crocus sativus L. (Saffron), could reduce the severity of DOX-induced cardiotoxicity. Therefore, this study was undertaken to assess the protective impact of CRO on DOX-induced cardiotoxicity in rats. The rats were divided into four groups: control, DOX (2mg/kg/48h, for 12days), and CRO groups that receiving DOX as in group 2 and CRO (20 and 40mg/kg/24h, for 20days) starting 4days prior to first DOX injection and throughout the study. Echocardiographic, electrocardiographic and hemodynamic studies, along with histopathological examination and MTT test were carried out. Our findings demonstrate that DOX resulted in cardiotoxicity manifested by decreased the left ventricular (LV) systolic and diastolic pressures, rate of rise/drop of LV pressure, ejection fraction, fractional shortening and contractility index, as compared to control group. In addition, histopathological analysis of heart confirmed adverse structural changes in myocardial cells following DOX administration. The results also showed that CRO treatment significantly improved DOX-induced heart damage, structural changes in the myocardium and ventricular function. In addition, CRO did not affect the in vitro antitumor activity of DOX. Taken together, our data confirm that CRO is protective against cardiovascular-related disorders produced by DOX, and clinical studies are needed to examine these findings in human.

The effects of crocin, insulin and their co-administration on the heart function and pathology in streptozotocin-induced diabetic rats

OBJECTIVE

Crocin is a saffron constituent with a potent anti-oxidant activity. The present study investigated the effects of crocin and insulin treatments (alone or in combination) on cardiac function and pathology in diabetic rats.

MATERIALS AND METHODS

Diabetes was induced by intraperitoneal (i.p.) injection of streptozotocin (STZ, 50 mg/kg). Thereafter, crocin (5, 10 and 20 mg/kg, i.p.), subcutaneous (s.c.) injection of insulin (4 IU/kg) and their combination were administered for eight weeks. Blood glucose level and whole heart and body weights were measured. Electrocardiography (ECG) was carried out using the lead II. Serum concentrations of lactate dehydrogenase (LDH), creatine kinase-MB isoenzyme (CK-MB), and the heart tissue malodialdehyde (MDA) and superoxide dismutase (SOD) contents were determined. The heart lesions were evaluated by light microscopy.

RESULTS

STZ decreased body weight and increased whole heart weight/body weight ratio. It also decreased heart rate, and increased RR and QT intervals and T wave amplitude. STZ increased blood glucose, serum LDH and CK-MB levels, augmented heart tissue MDA content, decreased SOD content of heart tissue, and produced hemorrhages, degeneration, interstitial edema, and fibroblastic proliferation in the heart tissue. Crocin (10 and 20 mg/kg, i.p.), insulin (4 IU/kg, s.c.) and their combination (5 mg/kg of crocin with 4 IU/kg of insulin) treatments recovered the ECG, biochemical and histopathological changes induced by STZ.

CONCLUSION

The results showed cardioprotective effects of crocin and insulin in STZ-induced diabetic rats. The antioxidant and anti-hyperglycemic properties of crocin and insulin may be involved in their cardioprotective actions.

The influence of different drying methods on constituents and antioxidant activity of saffron from china

More and more saffron has been cultivated in China because of the increasing saffron demand, but no paper has studied the influence of drying methods on the quality of Chinese saffron. In this paper, three different dehydration treatments applied in actual production were evaluated: dehydration with electric oven, vacuum oven, and microwave. We determined that the highest quality of saffron will be obtained when fresh saffron is treated at higher temperatures (no more than 70°C) for a long time by electric oven drying and vacuum oven drying. In microwave drying, treatments at lower microwave power and longer time benefit the quality of saffron. In addition, the influence of the drying method on antioxidants in saffron is discussed. The correlation between individual saffron profiles and the antioxidant value was estimated by spectrum-effect relationships analysis.