Skip to main content
Avicenna Journal of Phytomedicine logoLink to Avicenna Journal of Phytomedicine
. 2015 Sep-Oct;5(5):376–391.

The effects of Crocus sativus (saffron) and its constituents on nervous system: A review

Mohammad Reza Khazdair 1,2, Mohammad Hossein Boskabady 1, Mahmoud Hosseini 3,*, Ramin Rezaee 4, Aristidis M Tsatsakis 5
PMCID: PMC4599112  PMID: 26468457

Abstract

Saffron or Crocus sativus L. (C. sativus) has been widely used as a medicinal plant to promote human health, especially in Asia. The main components of saffron are crocin, picrocrocin and safranal. The median lethal doses (LD50) of C. sativus are 200 mg/ml and 20.7 g/kg in vitro and in animal studies, respectively. Saffron has been suggested to be effective in the treatment of a wide range of disorders including coronary artery diseases, hypertension, stomach disorders, dysmenorrhea and learning and memory impairments. In addition, different studies have indicated that saffron has anti-inflammatory, anti-atherosclerotic, antigenotoxic and cytotoxic activities. Antitussive effects of stigmas and petals of C. sativus and its components, safranal and crocin have also been demonstrated. The anticonvulsant and anti-Alzheimer properties of saffron extract were shown in human and animal studies. The efficacy of C. sativus in the treatment of mild to moderate depression was also reported in clinical trial. Administration of C. sativus and its constituents increased glutamate and dopamine levels in the brain in a dose-dependent manner. It also interacts with the opioid system to reduce withdrawal syndrome. Therefore, in the present article, the effects of C. sativus and its constituents on the nervous system and the possible underlying mechanisms are reviewed. Our literature review showed that C. sativus and its components can be considered as promising agents in the treatment of nervous system disorders.

Key Words: Crocus sativus, Nervous system, Safranal, Crocin, Saffron

Introduction

Crocus sativus L (C. sativus), commonly known as saffron, is a small perennial plant belonging to the family of Iridaceas. This plant is cultivated in many countries including Iran, Afghanistan, Turkey and Spain (Abdullaev, 1993). The stigmas of C. sativus are known to contain carotenoids, α-crocetin and glycoside crocin (responsible for saffron yellow color) and picrocrocin, the aglyconesafranal (responsible for saffron aroma) (Fernández and Pandalai, 2004; Champalab et al., 2011), the antioxidant carotenoids lycopene and zeaxanthin and vitamin B2(Vijaya Bhargava, 2011).

It has been shown that C. sativus stigma aqueous extract and its constituents, crocin but not safranal enhanced the sexual activity in male rats (Hosseinzadeh et al., 2008). Saffron and its constituentscrocin and safranal are also shown to be potent oxygen radical scavengers (Assimopoulou et al., 2005; Mashmoul et al., 2013; Farahmand et al., 2013).

In traditional medicine, C. sativus has been frequently used as an herbal sedative, antispasmodic, aphrodisiac, diaphoretic, expectorant, stimulant, stomachic, anticatarrhal, eupeptic, gingival sedative and emmenagogue (Nemati et al., 2008). C. sativus was experimentally shown to be effective in relieving symptoms of premenstrual syndrome (PMS). Following administration of saffron, a significant effect was observed in cycles 3 and 4 in the Total Premenstrual Daily Symptoms and Hamilton Depression Rating Scale which indicates the efficacy of C. sativus in the treatment of PMS (Agha-Hosseini et al., 2008).

Aqueous (500 mg/kg) and ethanolic extracts of C. sativus petals reduced blood pressure in a dose-dependent manner in rats (Fatehi et al., 2003). Administration of the aqueous extract of saffron petals (500 mg/kg) reduced blood pressure from 133.5±3.9 to 117±2.1 mmHg in rats. This reduction was postulated to be due to the effect of the extracts on the heart itself, total peripheral resistance or both (Fatehi et al., 2003). In rats isolated vas deferens, contractile responses to electrical field stimulation (EFS) were decreased by the petals extracts (Fatehi et al., 2003). EFS-induced contractions of vas deferens were shown to be mediated by noradrenaline and adenosine triphosphate (ATP) released as co-transmitters from sympathetic nerves (Hoyle and Burnstock, 1991). The ethanolic extract made more pronounced changes in EFS in rats isolated vas deferens whereas in guinea pig ileum, the aqueous extract of the plant was more effective (Fatehi et al., 2003). Crocin analogs isolated from saffron remarkably increased the blood flow in the retina and choroid and facilitated retinal function recovery; therefore, it could be used to treat ischemic retinopathy and/or age-related macular degeneration (Xuan, 1999). One study suggested that saffron exerted a significant cardioprotective effect by preserving hemodynamics and left ventricular functions (Sachdeva et al., 2012). Administration of C. sativus extractinpatients who had normal white blood cells (WBC) count, significantly increased WBC compared to crocin or placebo. Moreover, other hematologic factors were not changed significantly during 3 months of the study (Mousavi et al., 2015).

A potent stimulatory effect of C. sativus extract and safranal on β2-adrenoreceptors has also been reported (Nemati et al., 2008; Boskabady et al., 2010). In addition, blocking effect of safranal on muscarinic receptors (Boskabady et al., 2010) and the inhibitory effect of C. sativus on histamine (H1) receptors was reported, which proposed a competitive antagonistic effect for C. sativus on histamine (H1) receptors (Boskabady et al., 2010).

An in vitro study showed the inhibitory activity of saffron and crocin on amyloid beta-peptide fibrillogenesis and its protective action against H2O2–induced toxicity in human neuroblastoma cells (Papandreou et al., 2006, 2011). Additionally, administration of saffron (60 mg/kg body weight, i.p.) to normal and aged mice for one week, significantly improved learning and memory (Papandreou et al., 2011). Also, in vitro studies have confirmed the neuroprotective effects of saffron and its constituents in amnesic and ischemic rat models (Hosseinzadeh and Sadeghnia, 2005; Ochiai et al., 2007).

Considering clinical and animal experimental studies, the present review explores the important effects of C. sativus and its constituents on nervous system.

Methods

Information of this review article was collected by searching for the key-words "Crocus sativus", "nervous system", "clinical application", "animal studies", "crocin", "crocetin" and "safranal" in databases namely ISI Web of Knowledge, Medline/ Pubmed, Science direct, Scopus, Google Scholar, Embase, Biological Abstracts and Chemical Abstracts.

C. sativus constituents

More than 150 compounds have been identified in saffron stigma including colored carotenoids (e.g. crocetin and crocins as glycosidic derivatives), colorless monoterpene aldehydes, volatile agents (e.g. safranal and picrocrocin which are the bitter components), etc. (Bathaie and Mousavi, 2010). The traces of non-glycosylated carotenoids unrelated to crocetin are β-carotene, lycopene and zea-xanthin (Ríos et al., 1996). Ethanolic extract of saffron has visible absorption peaks at 427 and 452 nm. When excited at 435 nm, saffron emits at 543 nm (Horobin and Kiernan, 2002).

Crocetin isolated from saffron is one of the two principal chemicals responsible for the red color of saffron (Martin et al., 2002). Crocetin constitutes approximately 0.3% of the total weight of the saffron stigma (Escribano et al., 1996, Dris and Jain 2004). Crocetin can function as an acid (anionic) dye for biological staining because it has a carboxyl group at each end of the polyene chain which is easily dissolved in aqueous alkali solutions at pH ≥ 9. Crocetin is mostly present as trans isomer but cis-crocetin and its glycosides are also present in saffron as minor components (Melnyk et al., 2010).

Crocin belongs to a group of natural carotenoid commercially obtained from the dried stigma of C. sativus. It has a deep red color, forms crystals with a melting point of 186 oC and is easily soluble in water. Crocin is responsible for the color of saffron. Structure of crocin was elucidated by Karreeet al (1935). It is the main pigment of saffron (approx. 80% of pigment content). Pure crocin can be isolated from saffron extract and is directly crystallized (Karrer et al., 1932). Crocin is not orally absorbed. Crocins are hydrolyzed to crocetin before or during intestinal absorption, and the absorbed crocetin is partly metabolized to mono and diglucuronide conjugates (Asai et al., 2005).

Crocins, accounting for almost 6–16% of saffron dry weight (Gregory et al., 2005), are hydrophilic chemicals. α –crocin (crocin 1) is a carotenoid which comprises the majority of crocins found in saffron. It could be so easily dissolved in water that is used as color additive (Melnyk et al., 2010). The other color compounds of saffron are carotenoids and glycosidic, alpha-carotene, beta-carotene, lycopene, Zeaxanthingentiobioside, glycoside, gentio-glycoside, beta-crocetin di-glycoside and gama-crocetin.

Safranal (which is fat soluble) and pigments of the crocetin carotenoid are bitter, but the most important cause of saffron bitterness is picrocrocin (Abdullaev, 1993). Saffron lipophilic carotenoids are lycopene, alpha- and beta-carotene and zeaxanthin(Winterhalter and Straubinger, 2000; Tarantilis and Polissiou, 1997). Kaempferol has also been found in alcoholic extract of saffron petals (Gregory et al.,2005). Flavonoids especially lycopene, amino acids, proteins, starch, resins and other compounds have also been shown to be present in saffron (Assimopoulou et al.,2005). Saffron also has trace amounts of thiamine and riboflavin (Alonso et al.,2001).

Anticonvulsant effects

In Iranian folk medicine, C. sativus had been used as an anticonvulsant herb (Khosravan, 2002). Experimental studies also confirmed saffron anticonvulsant effects in rats and mice (Sunanda et al., 2014; Khosravan, 2002). Saffron at the doses of 400 and 800 mg/kg showed a significant antiepileptic activity in pentylenetetrazole (PTZ)-induced seizure model in a dose-dependent manner. However, saffron at the dose of 200 mg/kg did not significantly suppress PTZ- induced seizures (Sunanda et al., 2014). The anticonvulsant activities of aqueous and ethanolic extracts of saffron have been demonstrated in mice using maximal electroshock seizure (MES) and PTZ models (Khosravan, 2002).

Safranal (0.15 and 0.35 ml/kg, i.p.), reduced PTZ-induced seizure duration, delayed the onset of tonic convulsions and protected mice from death but crocin (200 mg/kg, i.p.) did not show anticonvulsant activity (Hosseinzadeh and Talebzadeh, 2005). Intraperitoneal administration of safranal (72.75, 145.5 and 291 mg/kg) decreased the frequency of minimal clonic seizures (MCS) and generalized tonic clonic seizures (GTCS) (Hosseinzadeh and Sadeghnia, 2007). Safranal also attenuated the acute experimental absence seizures which was attributed to modifications of benzodiazepine binding sites of GABAA receptor complex (Sadeghnia et al., 2008).

Anti-Alzheimer effects

Basic studies

Alzheimer's disease (AD) is described pathologically as deposition of amyloid β-peptide (Aβ) fibrils. The aqueous-ethanolic (50:50, v/v) extract of C. sativus stigmas has good antioxidant properties -higher than those of carrot and tomato- in a concentration and time-dependent manner which was accompanied by inhibition of Aβ fibrillogenesis. The trans-crocin-4, the digentibiosyl ester of crocetin was the main carotenoid constituent which inhibited Aβ fibrillogenesis (Papandreou et al., 2006). Intracerebroventricular (ICV) injection of streptozotocin (STZ) to rodents has been frequently used as an animal model for sporadic AD (Lannert and Hoyer, 1998; Labak et al., 2010; Veerendra Kumar and Gupta, 2003). It has been previously revealed that treatment by C. sativusextract (30 mg/kg) for 3 weeks could significantly improve cognition deficits induced by ICV injection of STZ in rats (Khalili et al., 2010).Crocin (30 mg/kg) has also been shown to have an antagonizing effect on the STZ-induced cognitive deficits in rats (Khalili and Hamzeh, 2010).

Geromichaloset al. (2012) showed that the saffron extract had a moderate (up to 30 %) inhibitory activity on acetyl-cholinesterase (AChE) and inhibited acetylcholine breakdown which is the main therapeutic approach for AD (Geromichalos et al., 2012).

Clinical studies

Administration of saffron 30 mg/day (15 mg twice daily) was found to be as effective as donepezil for treatment of mild-to-moderate AD in the subjects of 55 years and older (Akhondzadeh et al., 2010a ). In addition, the frequency of saffron extract side effects was similar to those of donepezil except for vomiting, which occurred more frequently in the donepezil group (Akhondzadeh et al., 2010a). In another study, 46 patients with mild-to-moderate AD were treated by saffron for 16 weeks. The results showed that the cognitive functions in saffron-treated group were significantly better than placebo (Akhondzadeh et al. 2010b).

Antidepressant and anti- schizophrenia effects

Basic studies

Crocin and ethanolic extracts of saffron are known to have antidepressant effect in rodents. Using forced swimming test, it was shown that crocin (50–600 mg/kg) reduced immobility time while increased climbing time (Hosseinzadeh et al., 2003). In other studies,effectiveness of antidepressant activity of C. sativus extract was described (Karimi et al., 2001; Yang Wang et al., 2010). The petroleum ether and dichloromethane fractions were suggested to be the active parts of corms of C. sativus. The petroleum ether fraction of the extract of C. sativus L. corms mainly contained n-tridecane, n-tetradecane, n-pentadecane, diethyltoluamide, n-catane and n-heptadecane, etc. (Yang Wang et al., 2010).

Kaempferol, a C. sativus petal constituent also reduced immobility behaviors in mice (100 and 200 mg/kg) and rats (50 mg/kg) (Hosseinzadeh et al., 2007). A decreased time of immobility in rodents caused by selective serotonin re-uptake inhibitors such as fluoxetine may explain the antidepressant effects of the plant (Cryan and Lucki, 2000; Lucki, 1997). The antidepressant effect of aqueous and ethanolic extracts of C. sativus petal and stigma has been shown in mice (Karimi et al., 2001). Major constituents of saffron, safranal and crocin, also had antidepressant activity in mice (Hosseinzadeh et al., 2004).

The effectiveness of C. sativus as a treatment for depression in animal model was shown in Table 1.

Table1.

The effectiveness of C. sativus as a treatment for depression in animal models

Constituent Animal Doses Results References
Aqueous and ethanolic extract Mice (0.2–0.8 g/kg) The aqueous and ethanolic extracts of stigma, reduced immobility time. Hosseinzadeh et al., 2003
Aqueous and ethanolic extract , Crocin Mice (50–600 mg/kg) Reduced immobility time and increased swimming time. Hosseinzadeh et al., 2003
Aqueous and ethanolic extract ,Safranal Mice (0.15–0.5 mL/kg) Reduced immobility time and increased swimming time. Hosseinzadeh et al., 2003
Kaempferol Mice 100 and 200 mg/kg Reduced immobility behaviors Hosseinzadeh et al., 2007

Clinical studies

In a randomized and double-blind clinical trial study, saffron supplementation statistically improved the mood of subjects compared to the placebo group. For six weeks, 30 mg/day of saffron was given and subjects were evaluated based on the Hamilton Depression Rating Scale (HAM-D) (Akhondzadeh et al., 2005). Another similar study by Noorbala et al. (2005) revealed that six-week administration of saffron extract (30 mg/day) was effective in the treatment of mild to moderate depression. These effects were similar to the effects of fluoxetine (Noorbala et al., 2005) and imipramine 100 mg/day (Akhondzadeh et al., 2004). Therapeutic benefits of petals of C. sativus in the treatment of mild to moderate depression have also been suggested (AkhondzadehBasti et al., 2007). The efficacy of co-administration of hydro-alcoholic extract of C. sativus (40 or 80 mg) and fluoxetine (30 mg/ day) was also investigated in a double- blind randomized clinical trial for six weeks. The results revealed that a dose of C. sativus 80 mg plus fluoxetine was more effective than that of C. sativus 40 mg and fluoxetine to treat mild to moderate depressive disorders (Moosavi et al., 2014).

Short-term administration of saffron (30 mg/day) capsules for six weeks was also shown to be as effective as fluoxetine (40 mg/day) in improving depression symptoms in patients who were suffering from major depressive disorder (MDD) after undergoing a percutaneous coronary intervention (Shahmansouri et al., 2014).

Another clinical study demonstrated that saffron aqueous extract (15 mg twice daily) andcrocin (15 mg twice daily) were well tolerated by patients with schizophrenia during the study and no serious side effects were observed (Mousavi et al., 2015).

The effectiveness of C. sativus as a treatment for depression in human studies was summarized in Table 2.

Table2.

The effectiveness of C. sativus as a treatment for depression in human studies.

Number of patients Treatments Time ofTreatment (weeks) Results References
30 Stigma of C. sativus30 mg/day 6 The effect of stigma of C. sativussimilar to imipramine in the treatment of mild to moderate depression Akhondzadeh et al.,2004
40 Stigma of C. sativus30 mg/day 6 The outcome on the Hamilton depression rating scale Stigma of C. sativuscould produce a significantly better than the placebo Akhondzadeh et al.,2005
40 Stigma of C. sativus30 mg/day 6 The effect of stigma of C. sativussimilar to fluoxetine in the treatment of mild to moderate depression Noorbala et al.,2005
40 Petal of C. sativus30 mg/day 6 The outcome on the Hamilton depression rating scale Petal of C. sativuscould produce a significantly better than the placebo Moshiri et al.,2006
40 Petal of C. sativus15 mg bid (morning and evening) 8 Petal of C. sativuswas found to be effective similar to fluoxetine in
The treatment of mild to moderate depression
AkhondzadehBasti et al., 2007
60 C. sativus40 and 80 mg/day+ fluoxetine (30 mg) 6 Was effective to treatment of mild to moderate depressive disorders Moosavi et al., 2014
40 Saffron(30 mg/day 6 Was effective as fluoxetine (40 mg/day) in improving depressive symptoms of patients who are suffering from major depressive disorder (MDD) Shahmansouri et al., 2014

Anti-Parkinson effects

Saffron and its components (mainly crocin, crocetin, and safranal) have been used in animal models with neurodegenerative diseases (Ochiai et al., 2007; Purushothuman et al., 2013). Crocin and safranal have inhibitory effect on fibrillation of apo alpha-lactalbumin (a-alpha-LA), under amyloidogenic conditions which crocin was found to be more effective than safranal. Formation of toxic amyloid structures is related with various neurodegenerative diseases such as Alzheimer’s and Parkinson’s diseases (Ebrahim-Habibi et al. 2010).

Neuroprotective effects of seven-day administration of crocetin (25, 50 and 75µg/kg body weight, i.p.) against 6-hydroxydopamine (6-OHDA, 10 µgintrastriatal)-induced Parkinson's disease in rats have been reported. Reduction in dopamine utilization by tissues was suggested as a possible mechanism (Ahmad et al., 2005). In another study, the protective effect of saffron pre-treatment on dopaminergic cells in the substantia nigra pars compacta (SNc) and retina in a mouse model of acute MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine)-induced Parkinson's disease was examined. BALB/c mice received MPTP or saline over a 30-hour period. Animals in the saffron-treated group received Saffron (0.01% w/v) dissolved in the drinking water for five days and control groups received normal tap water. After the six days, the brains were processed for tyrosine hydroxylase (TH) immunochemistry and TH+ cells count was reported using the optical fractionator method. In both the SNc and retina, the MPTP-injected mice had a reduced number of TH+ cells (30-35%) compared to saline-injected controls. Pre- treatment of MPTP-injected mice by saffron increased both SNc and retinal TH+ cell counts (25-35%) and closed them to the control levels. It was concluded that saffron pre-treatment saved many dopaminergic cells in the SNc and retina from Parkinsonian (MPTP) insult in mice (Purushothuman et al., 2013).

Effects of C. sativus on oxidative damages and neurotoxicity

It has been reported that crocin 10 μM inhibited the formation of peroxidized lipids in cultured PC12 cells, moderately restored superoxide dismutase (SOD) activity and maintained neurons morphology. While the antioxidant effect of crocin was comparable to that of α –tocopherol, it was even more pronounced at some concentrations.

Administration of C. sativus stigma extract (100 mg/kg, p.o.) for 7 days before induction of cerebral ischemia by middle cerebral artery occlusion (MCAO) remarkably reduced SOD, catalase and Na, K-ATPase activities and glutamate and aspartate concentrations induced by ischemia in rats (Saleem et al. 2006). Treatment with saffron extract (5 and 25 mg/ml) and crocin (10 and 50 μM) could decrease the neurotoxic effect of glucose in PC12 cells. The results showed that glucose (13.5 and 27 mg/ml) reduced PC12 cells viability while cell death was reduced by saffron and crocin pretreatment (Mousavi et al., 2010). Another study showed that administration of saffron extract (200 mg/kg) and honey syrup (500 mg/kg) for 45 days reduced the aluminium chloride-induced neurotoxicity in mice (Shati et al. 2011). Other studies showed that safranal has some protective effects on different markers of oxidative damage in hippocampal tissue from ischemic rats (Hosseinzadeh and Sadeghnia, 2005) and in hippocampal tissue following quinolinic acid (QA) administration (Sadeghnia et al., 2013). Safranal also reduced extracellular concentrations of glutamate and aspartate (excitatory amino acids) in the hippocampus of anaesthetized rats following kainic acid administration (Hosseinzadeh et al. 2008b).

In addition, crocin increased the activity of SOD and glutathione peroxidase (GPx) and remarkably reduced malondialdehyde (MDA) content in the ischemic cortex in rat model of ischemic stroke (Vakili et al., 2013). Co-administration of saffron extract with aluminium reversed aluminium-induced changes in monoamine oxidase (MAO-A, MAO-B) activity and the levels of lipid peroxidation in whole brain and cerebellum (Linardaki et al., 2013).

It has been suggested that exposure to high levels of glucocorticoids or chronic stress may lead to oxidative injury in the hippocampus, which may impair learning and memory functions (Behl et al., 1997; McIntosh et al., 1998a). Saffron extract and crocin can improve learning and memory (Abe and Saito, 2000, Pitsikas et al., 2007). It was demonstrated that saffron and crocin can prevent oxidative stress in the hippocampus and avoid deficits in spatial learning and memory (Ghadrdoost et al., 2011). It has been reported that crocetin increases the antioxidant potential in brain and helps to fight against 6-OHDA-induced neurotoxicity (Ahmad et al., 2005).

The aqueous extract of saffron (50, 100 and 200 mg/kg) prevented diazinon (20 mg/kg)-induced increase of inflammation, oxidative stress and neuronal damage biomarkers (Moallem et al., 2014).

Effects of C. sativus on neuronal injury and apoptosis

Crocin (30, 60 and 120 mg/kg) showed protective effect against ischemia/reperfusion injury and cerebral edema in a rat model of stroke and decreased infarct volume. Administration of crocin (60 mg/kg), one hour before, or one hour after the induction of ischemia, reduced brain edema (Vakili et al., 2013).

The neuroprotective effects of crocetin in the brain injury in animal studies have been suggested to be related to its ability to inhibit apoptosis at early stages of the injury and its ability to promote angiogenesis at the subacute stage as directed by higher expression levels of vascular endothelial growth factor receptor-2 (VEGFR-2) and serum response factor (SRF) (Bie et al., 2011).

A recent study showed that crocin (50 mg/kg) prevented retinalganglion cells (RGCs) apoptosis after retinal ischemia/reperfusion injury via phosphatidylinositol 3-kinase/AKT (PI3K/AKT) signaling pathway. In addition, crocin increased Bcl-2/BAX ratio (Qi et al., 2013). Crocin (10 µM)could suppress tumor necrosis factor alpha (TNF-α)-induced expression of proapoptotic mRNA which releases cytochrome c from mitochondria and it was suggested that crocin inhibits neuronal cell death induced by both internal and external apoptotic stimuli (Soeda et al., 2001). Moreover, crocetin can inhibit H2O2-induced RGC-5 cell death and inhibit caspase-3 and caspase-9 activity (Yamauchi et al., 2011).

In serum/glucose-deprived cells, lipid peroxidation may increase which can be inhibited by crocin. Crocin can suppress the activation of caspase-8 was and its antioxidant properties are more prounounced than α-tocopherol at the same concentration (Ochiai et al., 2004). In addition, crocin suppressed the activation of caspase-8 caused by serum/glucose deprivation (Ochiai et al., 2004a).

Crocin and tricrocin remarkably suppressed membrane lipid peroxidation, caspase-3 activation and cell death in serum-deprived and hypoxic PC12 cells which were more marked than those of tricrocin. Crocetin has been suggested to have some linked glucose esters (Ochiai et al., 2007). The results of this study suggested that dicrocin and picrocrocin had no effect on cell survival (Ochiai et al., 2007).

Effects of C. sativus on neuroinflammation

Crocin inhibited syncytin-1 and nitric oxide (NO)-induced astrocyte and oligodendrocyte cytotoxicity (Christensen, 2005) and reduced neuropathology in experimental autoimmune encephalomyelitis (EAE) with significantly less neurological impairments. Syncytin-1 has been contributed to oligodendrocyte death and neuroinflammation (Christensen, 2005; Antony et al., 2004). Syncytin-1 is highly expressed in astrocytes, microglia and in the glial cells of multiple sclerosis lesions (Barnett and Prineas, 2004).

Endoplasmic reticulum (ER) stress has been shown to be closely related to inflammatory pathways (Mori, 2009). It was shown that EAE increases the transcript levels of the ER stress genes XBP-1/s (Marciniak et al., 2004). Administration of crocin on day 7 post-EAE induction, suppressed ER stress and inflammatory gene expression in the spinal cord and also reduced the expression of ER stress genes XBP-1/s (Deslauriers et al., 2011).

C. sativus and the brain neurotransmitters

Ettehadi et al. (2013) showed that the aqueous extract of saffron (50, 100, 150 and 250 mg/kg, i.p.) increased brain dopamine concentration in a dose-dependent manner. Moreover, the extract had no effect on brain serotonin or norepinephrine concentration. In addition, the results showed that the aqueous extract of saffron especially at the dose of 250 mg/kg triggered and increased the production of important neurotransmitters including dopamine and glutamate in rat brain (Ettehadi et al., 2013).

The effects of saffron on conditioning place preference (CPP) induced by morphine has been reported to be similar to the effect of N-methyl-D-aspartate (NMDA) receptor antagonists (Hosseinzadeh et al., 2012 Lechtenberg et al., 2008). Furthermore, the analgesic effect of saffron can be reduced by NMDA receptor antagonists (Nasri et al., 2011). Therefore an interaction with glutamatergic system for saffron of its components might be postulated.

The NMDA receptors have also been well known to be involved in post-training memory processing by the amygdala and hippocampus (Izquierdo et al., 1992). The role of these receptors in morphine state-dependent learning has also been suggested (Zarrindast et al., 2006; Cestari and Castellano, 1997). Involvement of NMDA receptors in the effects of C. sativus or its constituents on memory has been shown (Lechtenberg et al., 2008; Abe et al., 1999). The beneficial effects of saffron on memory have also been suggested to be mediated by the cholinergic system (Pitsikas and Sakellaridis, 2006; Ghadami and Pourmotabbed, 2009).

C. sativus and opioids system

Saffron aqueous (80–320 mg/kg) and ethanolic (400–800 mg/kg) extracts reduced morphine withdrawal signs induced by naloxone in mice (Hosseinzadeh and Jahanian, 2010). Also, crocin (200 and 600 mg/Kg) could reduce withdrawal sign without reducing locomotor activities (Amin and Hosseinzadeh, 2012; Hosseinzadeh and Jahanian, 2010).

Intraperitoneal administration of ethanolic extract of saffron (10, 50 and 100 mg/Kg) and safranal (1, 5 and 10 mg/Kg) reduced theacquisition and expression of morphine CPP (Ghoshooniet al., 2011). Administration of crocin (400 and 600 mg/kg,i.p.) 30 min before morphine administration decreased the acquisition and reinstatement of morphine-induced CPP in mice (Imenshahidi et al., 2011). It has also been reported that 5 min after morphine (10 mg/kg) administration, injection of ethanolic extract of C. sativus stigma (5 and 10 µg/rat) into the nucleus accumbens shell part of rats, led to decrease in the time spent in drug paired side. In addition, injection of extract to the animals that received morphine (10 mg/kg), decreased the expression of morphine (CPP) (Mojabi et al., 2008). Injection of aqueous extract of saffron stigma (50, 100, 150 and 250mg/Kg,i.p.) showed an increased release of dopamine in rat brains. Also, this extract (only at 250 mg/Kg) significantly increased the release of glutamate (Ettehadi et al., 2013).

Administration of saffron extract (150 and 450 mg/kg) before retention trials also increased the time latency. So, saffron extract reduced morphine-induced memory impairment (Naghibi et al., 2012). Protective effect of saffron extract against morphine-induced inhibition of spatial learning and memory in rat has also been suggested (Haghighizad et al., 2008).

The effects of C. sativus on opioid receptors were showed in Table 3.

Table 3.

The effects of C. sativus on opioid system

C. Sativus or its constituents Dose Results References
Sa ron 150 and 450 mg/kg Improved learning and memory impairment induced by morphine Naghibi et al., 2012
Sa ron Aqueous (80, 160, 320 mg/kg) and ethanolic (400 and 800 mg/kg) extract Reduced naloxone precipitated jumping Ghoshooni et al., 2011; shams et al., 2009
Crocin 200 and 600 mg/kg Reduced withdrawal sign without reducing locomotor activity Amin and hosseinzadeh 2012
C. sativus stigma Alcohol extract (5 and 10 µg/rat) Decrease in the time spent in drug paired side Ghoshooni et al., 2011
Crocin 400 and 600 mg/kg Decreased the acquisition and reinstatement of morphine-induced cpp
Saffron 10, 50 and 100 mg/kg Reduced the acquisition and expression of morphine cpp
Safranal 1, 5 and 10 mg/kg Reduced the acquisition and expression of morphine cpp
Saffron 50, 100, 150 and 250mg/kg Increased the release of dopamine in rat brains and increased the release of glutamate only in dose 250 Ettehadi et al., 2013

Conclusion

Anti-oxidant and anti-inflammatory effects of the extracts of C. sativus and its constituents (crocetin, crocins, safranal) implies saffron therapeutic potential for various nervous system disorders. Based on the literature, beneficial effects of the plant and its components on neurodegenerative disorders such as Alzheimer and Parkinson's disease are mainly due to their interactions with cholinergic, dopaminergic and glutamatergic systems. It is assumed that saffron anticonvulsant and analgesic properties and its effects on morphine withdrawal and rewarding properties of morphine might be due to an interaction between saffron, GABA and opioid system.

According to human and animal studies, saffron and its constituents have been shown to be effective in the treatment of mild to moderate depression which may be because of an interaction with the serotonin and noradrenaline system. However, to have a detailed perspective of saffron effects on nervous system, more mechanistic investigations are highly advised.

Conflict of interest

There is no conflict of interest.

References

  1. Abdullaev F. Biological effects of saffron. BioFactors (Oxford England) 1993;4:83–86. [PubMed] [Google Scholar]
  2. Abe K, Saito H. Effects of saffron extract and its constituent crocin on learning behaviour and long-term potentiation. Phytother Res. 2000;14:149–152. doi: 10.1002/(sici)1099-1573(200005)14:3<149::aid-ptr665>3.0.co;2-5. [DOI] [PubMed] [Google Scholar]
  3. Abe K, Sugiura M, Yamaguchi S, Shoyama Y, Saito H. Saffron extract prevents acetaldehyde-induced inhibition of long-term potentiation in the rat dentate gyrus in vivo. Brain Res. 1999;851:287–289. doi: 10.1016/s0006-8993(99)02174-5. [DOI] [PubMed] [Google Scholar]
  4. Agha‐Hosseini M, Kashani L, Aleyaseen A, Ghoreishi A, Rahmanpour H, Zarrinara A, Akhondzadeh S. Crocus sativus L(saffron) in the treatment of premenstrual syndrome: a double‐blind randomised and placebo‐controlled trial. BJOG Int J Gynaecol Obstet. 2008;115:515–519. doi: 10.1111/j.1471-0528.2007.01652.x. [DOI] [PubMed] [Google Scholar]
  5. Ahmad AS, Ansari MA, Ahmad M, Saleem S, Yousuf S, Hoda MN, Islam F. Neuroprotection by crocetin in a hemi-parkinsonian rat model. Pharmacol Biochem Behav. 2005;81:805–813. doi: 10.1016/j.pbb.2005.06.007. [DOI] [PubMed] [Google Scholar]
  6. Akhondzadeh Basti A, Moshiri E, Noorbala AA, Jamshidi AH, Abbasi SH, Akhondzadeh S. Comparison of petal of Crocus sativus L and fluoxetine in the treatment of depressed outpatients: A pilot double-blind randomized trial. Prog Neuropsychopharmacol Biol Psychiatry. 2007;31:439–442. doi: 10.1016/j.pnpbp.2006.11.010. [DOI] [PubMed] [Google Scholar]
  7. Akhondzadeh S, Fallah-Pour H, Afkham K, Jamshidi A-H, Khalighi-Cigaroudi F. Comparison of Crocus sativus L and imipramine in the treatment of mild to moderate depression: a pilot double-blind randomized trial. BMC Complement Altern Med. 2004;4:12. doi: 10.1186/1472-6882-4-12. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Akhondzadeh S, Sabet MS, Harirchian M, Togha M, Cheraghmakani H, Razeghi S, Hejazi SS, Yousefi M, Alimardani R, Jamshidi A. Saffron in the treatment of patients with mild to moderate Alzheimer’s disease: a 16‐week, randomized and placebo‐controlled trial. J Clin Pharm Therapeut. 2010a;35:581–588. doi: 10.1111/j.1365-2710.2009.01133.x. [DOI] [PubMed] [Google Scholar]
  9. Akhondzadeh S, Sabet MS, Harirchian MH, Togha M, Cheraghmakani H, Razeghi S, Hejazi SS, Yousefi MH, Alimardani R, Jamshidi A. A 22-week, multicenter, randomized, double-blind controlled trial of Crocus sativus in the treatment of mild-to-moderate Alzheimer’s disease. Psychopharmacology. 2010b;207:637–643. doi: 10.1007/s00213-009-1706-1. [DOI] [PubMed] [Google Scholar]
  10. Akhondzadeh S, Tahmacebi‐Pour N, Noorbala AA, Amini H, Fallah‐Pour H, Jamshidi AH, Khani M. Crocus sativus L in the treatment of mild to moderate depression: a double‐blind randomized and placebo‐controlled trial. Phytother Res. 2005;19:148–151. doi: 10.1002/ptr.1647. [DOI] [PubMed] [Google Scholar]
  11. Alonso Gl, Salinas MR, Garijo J, Sánchez‐Fernández MA. Composition of crocins and picrocrocin from Spanish saffron (Crocus sativus L) JFood Quality. 2001;24:219–233. [Google Scholar]
  12. Amin B, Hosseinzadeh H. Evaluation of aqueous and ethanolic extracts of saffron, Crocus sativus L and its constituents, safranal and crocin in allodynia and hyperalgesia induced by chronic constriction injury model of neuropathic pain in rats. Fitoterapia. 2012;83:888–895. doi: 10.1016/j.fitote.2012.03.022. [DOI] [PubMed] [Google Scholar]
  13. Antony JM, van Marle G, Opii W, Butterfield DA, Mallet F, Yong VW, Wallace JL, Deacon RM, Warren K, Power C. Human endogenous retrovirus glycoprotein-mediated induction of redox reactants causes oligodendrocyte death and demyelination. Nat Neurosci. 2004;7:1088–1095–1095. doi: 10.1038/nn1319. [DOI] [PubMed] [Google Scholar]
  14. Asai A, Nakano T, Takahashi M, Nagao A. Orally administered crocetin and crocins are absorbed into blood plasma as crocetin and its glucuronide conjugates in mice. J Agric Food Chem. 2005;53:7302–7306. doi: 10.1021/jf0509355. [DOI] [PubMed] [Google Scholar]
  15. Assimopoulou A, Sinakos Z, Papageorgiou V. Radical scavenging activity of Crocus sativus L extract and its bioactive constituents. Phytother Res. 2005;19:997–1000. doi: 10.1002/ptr.1749. [DOI] [PubMed] [Google Scholar]
  16. Bathaie SZ, Mousavi SZ. New applications and mechanisms of action of saffron and its important ingredients. Crit Rev Food Sci Nutr. 2010;50:761–786. doi: 10.1080/10408390902773003. [DOI] [PubMed] [Google Scholar]
  17. Barnett MH, Prineas JW. Relapsing and remitting multiple sclerosis: pathology of the newly forming lesion. Ann Neurol. 2004;55:458–468. doi: 10.1002/ana.20016. [DOI] [PubMed] [Google Scholar]
  18. Behl C, Lezoualc'h F, Trapp T, Widmann M, Skutella T, Holsboer F. Glucocorticoids enhance oxidative stress-induced cell death in hippocampal neurons in vitro. Endocrinology. 1997;138:101–106. doi: 10.1210/endo.138.1.4835. [DOI] [PubMed] [Google Scholar]
  19. Bhargava V. Medicinal uses and pharmacological properties of Crocus sativus Linn (Saffron) Int J Pharmacy Pharmaceutical Science. 2011;3:22–26. [Google Scholar]
  20. Bie XD, Chen YQ, Zheng XS, Dai HB. The role of crocetin in protection following cerebral contusion and in the enhancement of angiogenesis in rats. Fitoterapia. 2011;82:997–1002. doi: 10.1016/j.fitote.2011.06.001. [DOI] [PubMed] [Google Scholar]
  21. Bieschke J, Zhang Q, Powers ET, Lerner RA, Kelly JW. Oxidative metabolites accelerate Alzheimer's amyloidogenesis by a two-step mechanism, eliminating the requirement for nucleation. Biochemistry. 2005;44:4977–4983. doi: 10.1021/bi0501030. [DOI] [PubMed] [Google Scholar]
  22. Boskabady MH, Rahbardar MG, Nemati H, Esmaeilzadeh M. Inhibitory effect of Crocus sativus (saffron) on histamine (H1) receptors of guinea pig tracheal chains. Die Pharmazie Int J Pharm Sci. 2010;65:300–305. [PubMed] [Google Scholar]
  23. Cestari V, Castellano C. “MK-801 potentiates morphine-induced impairment of memory consolidation in mice:involvement of dopaminergic mechanisms,”. Psychopharma-cology. 1997;133:1–6. doi: 10.1007/s002130050364. [DOI] [PubMed] [Google Scholar]
  24. Christensen T. Association of human endogenous retroviruses with multiple sclerosis and possible interactions with herpes viruses. Rev Med Virol. 2005;15:179–211. doi: 10.1002/rmv.465. [DOI] [PubMed] [Google Scholar]
  25. Cryan JF, Lucki I. Antidepressant-like behavioral effects mediated by 5-hydroxytryptamine2C receptors. J Pharmacol Exp Therapeut. 2000;295:1120–1126. [PubMed] [Google Scholar]
  26. Deslauriers AM, Afkhami-Goli A, Paul AM, Bhat RK, Acharjee S, Ellestad KK, Noorbakhsh F, Michalak M, Power C. Neuroinflammation and endoplasmic reticulum stress are coregulated by crocin to prevent demyelination and neurodegeneration. J Immunol. 2011;87:4788–99. doi: 10.4049/jimmunol.1004111. [DOI] [PubMed] [Google Scholar]
  27. Dris R, Jain SM. Production practices and quality assessment of food crops. In: Jain, S. Mohan., editor. Preharvest Practice. Volume 1. Springer; 2004. [Google Scholar]
  28. Ebrahim-Habibi MB, Amininasab M, Ebrahim-Habibi A, Sabbaghian M, Nemat-Gorgani M. Fibrillation of alpha-lactalbumin: effect of crocin and safranal, two natural small molecules from Crocus sativus. Biopolymers. 2010;93:854–865. doi: 10.1002/bip.21477. [DOI] [PubMed] [Google Scholar]
  29. Ettehadi Hosseinali, Seyedeh Nargesolsadat Mojabi, Mina Ranjbaran, Jamal Shams, Hedayat Sahraei, Mahdi Hedayati, Farzad A. Aqueous Extract of Saffron (Crocus sativus) Increases Brain Dopamine and Glutamate Concentrations in Rats. J Behav Brain Sci. 2013;3:315–319. [Google Scholar]
  30. Escribano J, Alonso G-L, Coca-Prados M, Fernández J-A. Crocin, safranal and picrocrocin from saffron (Crocus sativus L) inhibit the growth of human cancer cells in vitro. Cancer letters. 1996;100:23–30. doi: 10.1016/0304-3835(95)04067-6. [DOI] [PubMed] [Google Scholar]
  31. Farahmand SK, Samini F, Samini M, Samarghandian S. Safranal ameliorates antioxidant enzymes and suppresses lipid peroxidation and nitric oxide formation in aged male rat liver. Biogerontology. 2013;14:63–71. doi: 10.1007/s10522-012-9409-0. [DOI] [PubMed] [Google Scholar]
  32. Fatehi M, Rashidabady T, Fatehi-Hassanabad Z. Effects of Crocus sativus petals’ extract on rat blood pressure and on responses induced by electrical field stimulation in the rat isolated vas deferens and guinea-pig ileum. J ethnopharmacology. 2003;84:199–203. doi: 10.1016/s0378-8741(02)00299-4. [DOI] [PubMed] [Google Scholar]
  33. Fernández J-A, Pandalai S. Biology, biotechnology and biomedicine of saffron. Recent Res Devel Plant Sci. 2004;2:127–159. [Google Scholar]
  34. Geromichalos GD, Lamari FN, Papandreou MA, Trafalis DT, Margarity M, Papageorgiou A, Sinakos Z. Saffron as a source of novel acetylcholinesterase inhibitors: molecular docking and in vitro enzymatic studies. J Agric Food Chem. 2012;60:6131–6138. doi: 10.1021/jf300589c. [DOI] [PubMed] [Google Scholar]
  35. Ghadami MR, Pourmotabbed A. The effect of crocin on scopolamine induced spatial learning and memory deficits in rats. Physiol Pharmacol. 2009;12:287–295. [Google Scholar]
  36. Ghadrdoost B, Vafaei AA, Rashidy-Pour A, Hajisoltani R, Bandegi AR, Motamedi F, Haghighi S, Sameni HR, Pahlvan S. Protective effects of saffron extract and its active constituent crocin against oxidative stress and spatial learning and memory deficits induced by chronic stress in rats. Eur J Pharmacol. 2011;667:222–229. doi: 10.1016/j.ejphar.2011.05.012. [DOI] [PubMed] [Google Scholar]
  37. Ghoshooni H, Daryaafzoon M, Sadeghi-Gharjehdagi S, Zardooz H, Sahraei H, Tehrani SP, et al. Saffron (Crocus sativus) ethanolic extract and its constituent, safranal, inhibits morphine-induced place preference in mice. Pak J Biol Sci. 2011;14:939–944. doi: 10.3923/pjbs.2011.939.944. [DOI] [PubMed] [Google Scholar]
  38. Gregory MJ, Menary RC, Davies NW. Effect of drying temperature and air flow on the production and retention of secondary metabolites in saffron. JAgric Food Chem. 2005;53:5969–5975. doi: 10.1021/jf047989j. [DOI] [PubMed] [Google Scholar]
  39. Haghighizad H, Pourmotabbed A, Sahraei H. Protective effect of Saffron extract on morphine-induced inhibition of spatial learning and memory in rat. Physiol Pharmacol. 2008;12:170–179. [Google Scholar]
  40. Horobin RW, Kiernan JA, Commission BS. Conn's biological stains: a handbook of dyes, stains and fluorochromes for use in biology and medicine. Biological Stain Commission. 2002 [Google Scholar]
  41. Hosseinzadeh H, Jahanian Z. Effect of Crocus sativus L (saffron) Stigma and its Constituents, Crocin and Safranal, on Morphine Withdrawal Syndrome in Mice. Phytother Res. 2010;24:726–730. doi: 10.1002/ptr.3011. [DOI] [PubMed] [Google Scholar]
  42. Hosseinzadeh H, Karimi G, Niapoor M. Antidepressant effect of Crocus sativus L stigma extracts and their constituents, crocin and safranal, in mice. Acta Hort. 2004;650:435–45. [Google Scholar]
  43. Hosseinzadeh H, Motamedshariaty V, Hadizadeh F. Antidepressant effect of kaempferol, a constituent of saffron (Crocus sativus) petal, in mice and rats. Pharmacologyonline. 2007;2:367–370. [Google Scholar]
  44. Hosseinzadeh H, Sadeghnia , HR Safranal, a constituent of Crocus sativus (saffron), attenuated cerebral ischemia induced oxidative damage in rat hippocampus. J PharmPharm Sci. 2005:394–399. [PubMed] [Google Scholar]
  45. Hosseinzadeh H, Sadeghnia HR, Rahimi A. Effect of safranal on extracellular hippocampal levels of glutamate and aspartate during kainic acid treatment in anesthetized rats. Planta Med. 2008b;74:1441–1445. doi: 10.1055/s-2008-1081335. [DOI] [PubMed] [Google Scholar]
  46. Hosseinzadeh H, Talebzadeh F. Anticonvulsant evaluation of safranal and crocin from Crocus sativus in mice. Fitoterapia. 2005;76:722–724. doi: 10.1016/j.fitote.2005.07.008. [DOI] [PubMed] [Google Scholar]
  47. Hosseinzadeh H, ziaee T, sadeghi A. The effect of saffron, crocus sativus stigma, extract and its constituents, safranal and crocin on sexual behaviors in normal male rats. Phytomedicine. 2008;15:491–495. doi: 10.1016/j.phymed.2007.09.020. [DOI] [PubMed] [Google Scholar]
  48. Hosseinzadeh H, Sadeghnia HR. Protective effect of safranal on pentylenetetrazol-induced seizures in the rat: involvement of GABAergic and opioids systems. Phytomedicine. 2007;14:256–62. doi: 10.1016/j.phymed.2006.03.007. [DOI] [PubMed] [Google Scholar]
  49. Hoyle CH, Burnstock G. ATP receptors and their physiological roles. Adenosine in the Nervous System. 1991:43–76. [Google Scholar]
  50. Imenshahidi M, Zafari H, Hosseinzadeh H. Effects of crocin on the acquisition and reinstatement of morphine-induced conditioned place preference in mice. Pharmacologyonline. 2011;1:1007–1013. [Google Scholar]
  51. Izquierdo C, Da Cunha, Rosat R, Jerusalinsky D, Ferreira MBC, Medina JH. Neurotransmitter receptors involved in post-training memory processing by the amygdala, medial septum, and hippocampus of the rat. Behav Neur Biol. 1992;58:16–26. doi: 10.1016/0163-1047(92)90847-w. [DOI] [PubMed] [Google Scholar]
  52. Karimi GR, Hosseinzadeh H, KHALEGH PP. Study of antidepressant effect of aqueous and ethanolic extract of Crocus sativus in mice. Iran J Basic Med Sci. 2001;4:11–15. [Google Scholar]
  53. Karrer P, Benz F, Morf R, Raudnitz H, Stoll M, Takahashi T. Pflanzenfarbstoffe XLVI Konstitution des Crocetins und Bixins Synthese des Perhydro‐norbixins. Helvetica Chimica Acta. 1932;15:1399–1419. [Google Scholar]
  54. Khalili M, Hamzeh F. Effects of active constituents of Crocus sativus L crocin on streptozocin-induced model of sporadic Alzheimer's disease in male rats. Iran Biomed J. 2010;14:59. [PMC free article] [PubMed] [Google Scholar]
  55. Khalili M, Kiasalari Z, Rahmati B, Narenjkar J. Behavioral and Histological Analysis of Crocus Sativus Effect in Intracerebroventricular Streptozotocin Model of Alzheimer Disease in Rats. Iran J Pathol. 2010;5:27–33. [Google Scholar]
  56. Khavandgar S, Homayoun H, Zarrindast MR. The effect of L-NAME and L-arginine on impairment of memory formation and state-dependent learning induced by morphine in mice. Psychopharmacology. 2003;167:291–296. doi: 10.1007/s00213-002-1377-7. [DOI] [PubMed] [Google Scholar]
  57. Khosravan V. Anticonvulsant effects of aqueous and ethanolic extracts of Crocus sativus L stigmas in mice. Arc Iran Medi. 2002;5:44. [Google Scholar]
  58. Labak M, Foniok T, Kirk D, Rushforth D, Tomanek B, Jasiński A, Grieb P. Metabolic changes in rat brain following intracerebroventricular injections of streptozotocin: a model of sporadic Alzheimer’s disease. Brain Edema XIV. Springer; 2010. [DOI] [PubMed] [Google Scholar]
  59. Lannert H, Hoyer S. Intracerebroventricular administration of streptozotocin causes long-term diminutions in learning and memory abilities and in cerebral energy metabolism in adult rats. Behav Neurosci. 1998;112:1199. doi: 10.1037//0735-7044.112.5.1199. [DOI] [PubMed] [Google Scholar]
  60. Lechtenberg MD, Schepmann M, Niehues N, Hellenbrand B, ¨unsch W, Hensel A. Quality and functionality of saffron: quality control, species assortment and affinity of extract and isolated sa ff ron compounds to NMDA and σ 1(Sigma-1) receptors. Planta Medica. 2008; 74:764–772. doi: 10.1055/s-2008-1074535. [DOI] [PubMed] [Google Scholar]
  61. Lechtenberg M, Schepmann D, Niehues M, Hellenbrand N, unsch WB, Hensel A. Quality and functionality of saffron: quality control, species assortment and affinity of extract and isolated saffron compounds to NMDA and σ 1(Sigma-1) receptors. Plant Med. 2008;74:764–772. doi: 10.1055/s-2008-1074535. [DOI] [PubMed] [Google Scholar]
  62. Linardaki ZI, Orkoula MG, Kokkosis AG, Lamari FN, Margarity M. Investigation of the neuroprotective action of saffron (Crocus sativus L) in aluminumexposed adult mice through behavioral and neurobiochemical assessment. Food Chem Toxicol. 2013;52:163–170. doi: 10.1016/j.fct.2012.11.016. [DOI] [PubMed] [Google Scholar]
  63. Lucki I. The forced swimming test as a model for core and component behavioral effects of antidepressant drugs. Behav pharmacol. 1997;8:523–532. doi: 10.1097/00008877-199711000-00010. [DOI] [PubMed] [Google Scholar]
  64. Marciniak SJ, Yun CY, Oyadomari S, Novoa I, Zhang Y, Jungreis R, Nagata K, Harding HP, Ron D. CHOP induces death by promoting protein synthesis and oxidation in the stressed endoplasmic reticulum. Genes Dev. 2004;18:3066. doi: 10.1101/gad.1250704. [DOI] [PMC free article] [PubMed] [Google Scholar]
  65. Mashmoul M, Azlan A, Khaza'ai H, Yusof Bnm, Noor Sm. Saffron: A natural potent antioxidant as a promising anti-obesity drug. Antioxidants. 2013;2:293–308. doi: 10.3390/antiox2040293. [DOI] [PMC free article] [PubMed] [Google Scholar]
  66. Martin G, Goh E, Neff A. Evaluation of the developmental toxicity of crocetin on Xenopus. Food chem toxicol. 2002;40:959–964. doi: 10.1016/s0278-6915(02)00040-6. [DOI] [PubMed] [Google Scholar]
  67. Melnyk JP, Wang S, Marcone MF. Chemical and biological properties of the world's most expensive spice: Saffron. Food Res Int. 2010;43:1981–1989. [Google Scholar]
  68. Moallem SA, Hariri AT, Mahmoudi M, Hosseinzadeh H. Effect of aqueous extract of Crocus sativus L (saffron) stigma against subacute effect of diazinon on specific biomarkers in rats. Toxicol Ind Health. 2014;30:141–6. doi: 10.1177/0748233712452609. [DOI] [PubMed] [Google Scholar]
  69. Moshiri E, Akhondzadeh BastiA, Noorbala AA, Jamshidi AH, Abbasi SH, Akhondzadeh S. Crocus sativus L(petal) in the treatment of mild-to-moderate depression: A double-blind, randomized and placebo-controlled trial. Phytomedicine. 2006;13:607–611. doi: 10.1016/j.phymed.2006.08.006. [DOI] [PubMed] [Google Scholar]
  70. Moosavi SM, Ahmadi M, Amini M, Vazirzadeh B, Sari I. The Effects of 40 and 80 mg Hydro-alcoholic Extract of Crocus Sativus in the Treatment of Mild to Moderate Depression. J Mazandaran Univ Med Sci (JMUMS) 2014:24. [Google Scholar]
  71. Mousavi B BS, Fadai F, Ashtari Z, Ali beige N, Farhang S, Hashempour S, Shahhamzei N, Heidarzadeh H. Safety evaluation of saffron stigma (Crocus sativus L) aqueous extract and crocin in patients with schizophrenia. Avicenna J Phytomed. 2015 Epub. [PMC free article] [PubMed] [Google Scholar]
  72. Mousavi SH, Tayarani NZ, Parsaee H. Protective effect of saffron extract and crocin on reactive oxygen species-mediated high glucose-induced toxicity in PC12 cells. Cell Mol Neurobiol. 2010;30:185–191. doi: 10.1007/s10571-009-9441-z. [DOI] [PMC free article] [PubMed] [Google Scholar]
  73. Naghibi SM, Mahmoud Hosseini, Fatemeh Khani, Motahare Rahimi, Farzaneh Vafaee, Hassan Rakhshandeh, Azita Aghaie. Effect of Aqueous Extract ofCrocus sativus L on Morphine-Induced Memory Impairment. Adv Pharmacol Sci. 2012 doi: 10.1155/2012/494367. Article ID 494367, 7 pages. [DOI] [PMC free article] [PubMed] [Google Scholar]
  74. Nasri S, Sahraei H, Zardooz H. Inhibition of pain and inflamation induced by formalin in male mice by ethanolicextract of sa ff ron (Crocus sativus) and its constituents crocin and safranal. Kowsar Med J. 2011;15:189–195. [Google Scholar]
  75. Nemati H BM, Ahmadzadef Vostakolaei H. Stimulatory effect of crocus sativus (saffron) on beta2-adrenoceptors of guinea pig tracheal chains. Phytomedicine. 2008;15:1038–1045. doi: 10.1016/j.phymed.2008.07.008. [DOI] [PubMed] [Google Scholar]
  76. Nilakshi N, Gadiya RV, Abhyankar M, Champalal KD. Detailed profile of Crocus sativus. Int J Pharma Bio Sciences. 2011;2:530–540. [Google Scholar]
  77. Noorbala A, Akhondzadeh S, Tahmacebi-Pour N, Jamshidi A. Hydro-alcoholic extract of Crocus sativus L versus fluoxetine in the treatment of mild to moderate depression: a double-blind, randomized pilot trial. J Ethnopharmacol. 2005;97:281–284. doi: 10.1016/j.jep.2004.11.004. [DOI] [PubMed] [Google Scholar]
  78. Ochiai T, Ohno S, Soeda S, Tanaka H, Shoyama Y, Shimeno H. Crocin prevents the death of rat pheochromyctoma (PC-12) cells by its antioxidant effects stronger than those of α -tocopherol. Neurosci Lett. 2004a;362:61–64. doi: 10.1016/j.neulet.2004.02.067. [DOI] [PubMed] [Google Scholar]
  79. Ochiai T, Shimeno H, Mishima K, Iwasaki K, Fujiwara M, Tanaka H, Shoyama Y, Toda A, Eyanagi R, Soeda S. Protective effects of carotenoids from saffron on neuronal injury in vitro and in vivo. Biochim Biophys Acta. 2007;1770:578–584. doi: 10.1016/j.bbagen.2006.11.012. [DOI] [PubMed] [Google Scholar]
  80. Ochiai T, Soeda S, Ohno S, Tanaka H, Shoyama Y, Shimeno H. Crocin prevents the death of PC-12 cells through sphingomyelinase-ceramide signaling by increasing glutathione synthesis. Neurochem Int. 2004;44:321–330. doi: 10.1016/s0197-0186(03)00174-8. [DOI] [PubMed] [Google Scholar]
  81. Papandreou MA, Polissiou MG, Efthimiopoulos S, Cordopatis P, Margarity M, Lamari FN. Inhibitory activity on amyloid-beta aggregation and antioxidant properties of Crocus sativus stigmas extract and its crocin constituents. J Agric Food Chem. 2006;54:8762–8768. doi: 10.1021/jf061932a. [DOI] [PubMed] [Google Scholar]
  82. Papandreou MA, Tsachaki M, Efthimiopoulos S, Cordopatis P, Lamari FN, Margarity M. Memory enhancing effects of saffron in aged mice are correlated with antioxidant protection. Behav Brain Res. 2011;219:197–204. doi: 10.1016/j.bbr.2011.01.007. [DOI] [PubMed] [Google Scholar]
  83. Pitsikas N, Zisopoulou S, Tarantilis PA, Kanakis CD, Polissiou MG, Sakellaridis N. Sakellaridis. Effects of the active constituents of Crocus sativusL crocins on recognition and spatial rats' memory. Behav Brain Res. 2007;83:141–146. doi: 10.1016/j.bbr.2007.06.001. [DOI] [PubMed] [Google Scholar]
  84. Pitsikas N, Sakellaridis N. Crocus sativus L. extracts antagonize memory impairments in di ff erent behavioural tasks in the rat. Behav Brain Res. 2006;173:112–115. doi: 10.1016/j.bbr.2006.06.005. [DOI] [PubMed] [Google Scholar]
  85. Purushothuman S, Nandasena C, Peoples CL, El Massri N, Johnstone DM, Mitrofanis J, Stone J. Saffron pre-treatment offers neuroprotection to Nigral and retinal dopaminergic cells of MPTP-Treated mice. J Parkinsons Dis. 2013;3:77–83. doi: 10.3233/JPD-130173. [DOI] [PubMed] [Google Scholar]
  86. Rios J, Recio M, Giner R, Manez S. An update review of saffron and its active constituents. Phytother Res. 1996;10:189–193. [Google Scholar]
  87. Qi Y, Chen L, Zhang L, Liu WB, Chen XY, Yang XG. Crocin prevents retinal ischaemia/reperfusion injury-induced apoptosis in retinal ganglion cells through the PI3K/AKT signalling pathway. Exp Eye Res. 2013;107:44–51. doi: 10.1016/j.exer.2012.11.011. [DOI] [PubMed] [Google Scholar]
  88. Sachdeva J, Tanwar V, Golechha M, Siddiqui KM, Nag TC, Ray R, Kumari S, Arya DS. Crocus sativus L(saffron) attenuates isoproterenol-induced myocardial injury via preserving cardiac functions and strengthening antioxidant defense system. Exper Toxicol Pathol. 2012;64:557–564. doi: 10.1016/j.etp.2010.11.013. [DOI] [PubMed] [Google Scholar]
  89. Sadeghnia HR, Kamkar M, Assadpour E, Boroushaki MT, Ghorbani A. Protective effect of safranal, a constituent of Crocus sativus , on quinolinic acid-induced oxidative damage in rat hippocampus. Iran J Basic Med Sci. 2013;16:73–82. [PMC free article] [PubMed] [Google Scholar]
  90. Sadeghnia H, Cortez M, Liu D, Hosseinzadeh H, Snead 3rd OC. Antiabsence effects of safranal in acute experimental seizure models: EEG and autoradiography. J Pharm Pharm Sci. 2008;11:1–14. doi: 10.18433/j38g6j. [DOI] [PubMed] [Google Scholar]
  91. Saleem S, Ahmad M, Ahmad AS, Yousuf S, Ansari MA, Khan MB, Ishrat T, Islam F. Effect of Saffron ( Crocus sativus ) on neurobehavioral and neurochemical changes in cerebral ischemia in rats. J Med Food. 2006;9:246–253. doi: 10.1089/jmf.2006.9.246. [DOI] [PubMed] [Google Scholar]
  92. Shahmansouri N, Farokhnia M, Abbasi S-H, Kassaian SE, Noorbala Tafti A-A, Gougol A, Yekehtaz H, Forghani S, Mahmoodian M, Saroukhani S. A randomized, double-blind clinical trial comparing the efficacy and safety of Crocus sativus L with fluoxetine for improving mild to moderate depression in post percutaneous coronary intervention patients. J Affect Disord. 2014;155:216–222. doi: 10.1016/j.jad.2013.11.003. [DOI] [PubMed] [Google Scholar]
  93. Shati AA, Elsaid FG, Hafez EE. Biochemical and molecular aspects of aluminium chloride-induced neurotoxicity in mice and the protective role of Crocus sativus L extraction and honey syrup. Neuroscience. 2011;175:66–74. doi: 10.1016/j.neuroscience.2010.11.043. [DOI] [PubMed] [Google Scholar]
  94. Soeda S, Ochiai T, Paopong L, Tanaka H, Shoyama Y, Shimeno H. Crocin suppresses tumor necrosis factor-alpha-induced cell death of neuronally differentiated PC-12 cells. Life Sci. 2001;69:2887–2898. doi: 10.1016/s0024-3205(01)01357-1. [DOI] [PubMed] [Google Scholar]
  95. Sugiura M, Shoyama Y, Saito H, Abe K. Crocin (crocetin di-gentiobiose ester) prevents the inhibitory effect of ethanol on long-term potentiation in the dentate gyrus in vivo. J Pharmacol Exper Therap. 1994;271:703–707. [PubMed] [Google Scholar]
  96. Sunanda BPV, RammohanB , Amitabh kumar, Kudagi BL. The effective study of aqueous extract of crocus sativus linn In chemical induced convulsants in rats. World J Pharm Pharm Sci. 2014;3:1175–1182. [Google Scholar]
  97. Srivastava R, Ahmed H, Dixit R. Crocus sativus L a comprehensive review. Pharmacogn Rev. 2010;4:200. doi: 10.4103/0973-7847.70919. [DOI] [PMC free article] [PubMed] [Google Scholar]
  98. Tarantilis PA, Polissiou MG. Isolation and identification of the aroma components from saffron (Crocus sativus) J Agricul Food Chem. 1997;45:459–462. [Google Scholar]
  99. Vakili A, Einali MR, Bandegi AR. Protective Effect of crocin against cerebral ischemia in a dose- dependent manner in a rat model of ischemic stroke. J Stroke Cerebrovasc Dis. 2013 doi: 10.1016/j.jstrokecerebrovasdis.2012.10.008. S1052–3057(12)00345-X (in press) [DOI] [PubMed] [Google Scholar]
  100. Veerendra Kumar M, Gupta Y. Effect of Centella asiatica on cognition and oxidative stress in an intracerebroventricular streptozotocin model of Alzheimer's disease in rats. Clin Experiment Pharmacol Physiol. 2003;30:336–342. doi: 10.1046/j.1440-1681.2003.03842.x. [DOI] [PubMed] [Google Scholar]
  101. Wang Y, Han T, Zhu Y, Zheng C-J, Ming Q-L, Rahman K, Qin L-P. Antidepressant properties of bioactive fractions from the extract of Crocus sativus L. J Nat Med. 2010;64:24–30. doi: 10.1007/s11418-009-0360-6. [DOI] [PubMed] [Google Scholar]
  102. Winterhalter P, Straubinger M. Saffron—renewed interest in an ancient spice. Food Rev Int. 2000;16:39–59. [Google Scholar]
  103. Xuan B, Zhou Y-H, Li N, Min Z-D, Chiou GC. Effects of crocin analogs on ocular blood flow and retinal function. J Ocular Pharmacol Therap. 1999;15:143–152. doi: 10.1089/jop.1999.15.143. [DOI] [PubMed] [Google Scholar]
  104. Yamauchi M, Tsuruma K, Imai S, Nakanishi T, Umigai N, Shimazawa M, Hara H. Crocetin prevents retinal degeneration induced by oxidative and endoplasmic reticulum stresses via inhibition of caspase activity. Eur J Pharmacol. 2011;650:110–119. doi: 10.1016/j.ejphar.2010.09.081. [DOI] [PubMed] [Google Scholar]
  105. Zarrindast MR, Jafari-Sabet M, Rezayat M, Djahanguiri B, Rezayof A. Involvement of NMDA receptors in morphine state-dependent learning in mice. Int J Neurosci. 2006;116:731–743. doi: 10.1080/00207450600675068. [DOI] [PubMed] [Google Scholar]
  106. Ziaee Toktam, Bibi Marjan Razavi, Hossein Hosseinzadeh. Saffron Reduced Toxic Effects of its Constituent, Safranal, in Acute and Subacute Toxicities in Rats. Jundishapur J Nat Pharm Prod. 2014;9:3–8. doi: 10.17795/jjnpp-13168. [DOI] [PMC free article] [PubMed] [Google Scholar]
  107. Zhang YY, Shoyama M, Sugiura Saito H. Eects of Crocus sativus L on the ethanol-induced impairment of passive avoidance performances in mice. Biol Pharm Bulletin. 1994;17:217–221. doi: 10.1248/bpb.17.217. [DOI] [PubMed] [Google Scholar]
  108. Zhang Q, Powers Et, Nieva J, Huff Me, Dendle Ma, Bieschke J, Glabe CG, Eschenmoser A, Wentworth P, Lerner Ra. Metabolite-initiated protein misfolding may trigger Alzheimer's disease. Proc Natl Acad Sci U S A. 2004;101:4752–4757. doi: 10.1073/pnas.0400924101. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Avicenna Journal of Phytomedicine are provided here courtesy of Mashhad University of Medical Sciences

RESOURCES