The Effect of Chronic Administration of Saffron (Crocus sativus) Stigma Aqueous Extract on Systolic Blood Pressure in Rats

Effects of saffron (Crocus sativus L.) supplementation on cardiometabolic Indices in diabetic and prediabetic overweight patients: a systematic review and meta-analysis of RCTs

BACKGROUND

The incidence of diabetes mellitus (DM) is increasing worldwide, and there is growing interest in the potential use of natural compounds as an alternative treatment for managing DM. Several research studies have investigated the impact of saffron consumption on managing and improving metabolic profiles in patients with DM, and they have shown promising results.

OBJECT

The study aims to systematically review and perform a meta-analysis to evaluate the potential effects of saffron and its extract on cardiometabolic indicators in diabetic and prediabetic overweight patients.

METHODS

We conducted a comprehensive systematic review and meta-analysis, searching PubMed, Scopus, Web of Science, Embase, and Google Scholar for all relevant studies published before April 20, 2024. We extracted weighted (WMD) or standardized (SMD) mean differences (before-after) and 95% confidence intervals (95%CI) of the outcomes and conducted meta-analyses using R. The study protocol was registered in PROSPERO (CRD42024538380).

RESULTS

Out of the studies screened, 15 RCTs were selected for inclusion in the systematic review and meta-analysis. These studies collectively involved 869 participants, 438 in the intervention group and 431 in the control group. Notably, our results showed that saffron supplementation led to significant changes in FBS (MD: - 8.75 mg/dL, 95% CI [- 14.75; - 2.76], P < 0.01), HbA1C (MD: - 0.34%, 95% CI [- 0.39; - 0.9], P < 0.01), TG (MD: - 13.28 mg/dL, 95% CI [- 22.82; - 3.75], P < 0.01), SBP (MD: - 5.33 mmHg, 95% CI [- 8.99-1.67], P = 0.04), DBP (MD: - 1.02 mmHg, 95% CI [- 3.91; 1.86], P = 0.03), AST (MD: - 1.32 IU/L, 95% CI [- 1.72, - 0.93], P < 0.01) levels in T2DM patients compared to placebo or no supplementation, indicating its potential as a therapeutic intervention. However, there was no significant effect on Insulin secretion (MD: - 0.15 µU/ml, 95% CI [- 2.1763; 1.8689], P = 0.88), HOMA (MD: - 0.35%, 95% CI [- 1.34;0.63], P = 0.48), TC (MD: - 4.86 mg/dL, 95% CI [- 9.81-0.09], P = 0.54), HDL (MD: 0.18 mg/dL, 95% CI [- 0.93; 1.29], P = 0.74), LDL (MD: - 1.77 mg/dL, 95% CI [- 5.99-2.45], P = 0.41), TNF-α (MD: - 0.34 pg/mL, 95% CI [- 0.99-0.30], P = 0.29), creatinine (MD: 2.83 mg/dL, 95% CI [2.29, 3.37], P = 0.31) and BUN (MD: - 0.44 mg/dL, 95% CI [- 1.43, 0.55], P = 0.38).

CONCLUSION

Saffron may improve specific CMI indices in overweight patients with diabetes or prediabetes, including significant reductions in FBS, HbA1C, TG, SBP, and AST. However, it did not significantly affect HDL, TC, LDL, insulin secretion, HOMA, DBP, TNF-α, ALT, Cr, or BUN. Further research with more trials and extended follow-up periods is needed to confirm and expand these findings.

Current Knowledge of the Antidepressant Activity of Chemical Compounds from Crocus sativus L

Psychotropic effect of Crocus sativus L. (family Iridaceae) biologically active chemical compounds are quite well documented and they can therefore be used in addition to the conventional pharmacological treatment of depression. This systematic review on antidepressant compounds in saffron crocus and their mechanisms of action and side effects is based on publications released between 1995−2022 and data indexed in 15 databases under the following search terms: antidepressant effect, central nervous system, Crocus sativus, cognitive impairement, crocin, crocetin, depression, dopamine, dopaminergic and serotonergic systems, picrocrocin, phytotherapy, neurotransmitters, safranal, saffron, serotonin, and biologically active compounds. The comparative analysis of the publications was based on 414 original research papers. The investigated literature indicates the effectiveness and safety of aqueous and alcoholic extracts and biologically active chemical compounds (alkaloids, anthocyanins, carotenoids, flavonoid, phenolic, saponins, and terpenoids) isolated from various organs (corms, leaves, flower petal, and stigmas) in adjuvant treatment of depression and anxiety. Monoamine reuptake inhibition, N-methyl-d-aspartate (NMDA) receptor antagonism, and gamma-aminobutyric acid (GABA)-α agonism are the main proposed mechanism of the antidepressant action. The antidepressant and neuroprotective effect of extract components is associated with their anti-inflammatory and antioxidant activity. The mechanism of their action, interactions with conventional drugs and other herbal preparations and the safety of use are not fully understood; therefore, further detailed research in this field is necessary. The presented results regarding the application of C. sativus in phytotherapy are promising in terms of the use of herbal preparations to support the treatment of depression. This is particularly important given the steady increase in the incidence of this disease worldwide and social effects.

Chemoprevention effect of the Mediterranean diet on colorectal cancer: Current studies and future prospects

Colorectal cancer (CRC) is the third most common cancer and the second most deadly cancer worldwide. Nevertheless, more than 70% of CRC cases are resulted from sporadic tumorigenesis and are not inherited. Since adenoma-carcinoma development is a slow process and may take up to 20 years, diet-based chemoprevention could be an effective approach in sporadic CRC. The Mediterranean diet is an example of a healthy diet pattern that consists of a combination of nutraceuticals that prevent several chronic diseases and cancer. Many epidemiological studies have shown the correlation between adherence to the Mediterranean diet and low incidence of CRC. The goal of this review is to shed the light on the anti-inflammatory and anti-colorectal cancer potentials of the natural bioactive compounds derived from the main foods in the Mediterranean diet.

Safranal Induces Vasorelaxation by Inhibiting Ca2+ Influx and Na+/Ca2+ Exchanger in Isolated Rat Aortic Rings

Introduction: Safranal, which endows saffron its unique aroma, causes vasodilatation and has a hypotensive effect in animal studies, but the mechanisms of these effects are unknown. In this study, we investigated the mechanisms of safranal vasodilation. Methods: Isolated rat endothelium-intact or -denuded aortic rings were precontracted with phenylephrine and then relaxed with safranal. To further assess the involvement of nitric oxide, prostaglandins, guanylate cyclase, and phospholipase A₂ in safranal-induced vasodilation, aortic rings were preincubated with L-NAME, indomethacin, methylene blue, or quinacrine, respectively, then precontracted with phenylephrine, and safranal concentration–response curves were established. To explore the effects of safranal on Ca²⁺ influx, phenylephrine and CaCl₂ concentration–response curves were established in the presence of safranal. Furthermore, the effect of safranal on aortic rings in the presence of ouabain, a Na⁺-K⁺ ATPase inhibitor, was studied to explore the contribution of Na⁺/Ca²⁺ exchanger to this vasodilation. Results: Safranal caused vasodilation in endothelium-intact and endothelium-denuded aortic rings. The vasodilation was not eliminated by pretreatment with L-NAME, indomethacin, methylene blue, or quinacrine, indicating the lack of a role for NO/cGMP. Safranal significantly inhibited the maximum contractions induced by phenylephrine, or by CaCl₂ in Ca²⁺-free depolarizing buffer. Safranal also relaxed contractions induced by ouabain, but pretreatment with safranal totally abolished the development of ouabain contractions. Discussion/Conclusion: Inhibition of Na⁺-K⁺ ATPase by ouabain leads to the accumulation of Na⁺ intracellularly, forcing the Na⁺/Ca²⁺ exchanger to work in reverse mode, thus causing a contraction. Inhibition of the development of this contraction by preincubation with safranal indicates that safranal inhibited the Na⁺/Ca²⁺ exchanger. We conclude that safranal vasodilation is mediated by the inhibition of calcium influx from extracellular space through L-type Ca²⁺ channels and by the inhibition of the Na⁺/Ca²⁺ exchanger.

Crocin restores the balance of Th1/Th2 immune cell response in ConA-treated human lymphocytes

BACKGROUND

Following antigen stimulation, naive CD4⁺ T cells differentiate into different T helper (Th) subsets characterized by lineage-specific transcriptional factors and cytokines. The balance between cytokines from Th1 and Th2 cells is disrupted in autoimmune disorders, asthma, and allergic reactions. Crocin, the major carotenoid of saffron, has anti-inflammatory properties. We investigated crocin modifying effects on the human lymphocytes proliferation and Th1/Th2 balance as a possible mechanism of its anti-inflammatory effects.

METHODS

The human peripheral blood mononuclear cells were isolated using Ficoll density gradient centrifugation. MTT was used to evaluate the effect of 72-h treatment with different concentrations of crocin with or without ConA on lymphocytes proliferation. INF-γ/IL-4 cytokine secretion and T-bet/GATA-3 transcription factor expression ratios (as indicators of Th1/Th2 response status) were measured in non-stimulated and ConA-stimulated cells in the presence or absence of crocin by ELISA and RT-qPCR methods, respectively.

RESULTS

The results showed crocin at a concentration of 50 μM and higher was toxic for human lymphocytes, and at a non-toxic concentration of 25 µM, it did not affect cell proliferation. The ratio of T-bet/GATA-3 and INF-γ/IL-4 was higher in the culture supernatant of ConA-stimulated cells compared to non-stimulated ones. Crocin-treated cells showed slightly lower T-bet/GATA-3 and INF-γ/IL-4 ratios compared to untreated cells. Crocin (25 μM) was also able to restore the increased ratio of Th1/Th2 immune response induced by ConA.

CONCLUSIONS

Crocin can alleviate inflammatory-stimulant effects of ConA on human lymphocytes by decreasing T-bet/GATA-3 and INF-γ/IL-4 ratios, which are indicative of restoring the balance of Th1/Th2 responses.

K, P. UD. Spices and Hypertension: An Insight for Researchers

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Hypertension is a global public health concern since it can lead to complications like stroke, heart disease, and kidney failure. These complications can add to a disability, increase healthcare costs, and can even result in mortality. In spite of the availability of a large number of anti-hypertensive drugs, the control of blood pressure is suboptimal in many patients. Spices have been used as flavouring agents and in treating diseases in folk medicine since they are considered to be rich sources of phytochemicals, especially polyphenols. Hence, during recent years, there has been renewed interest among researchers in exploring natural sources, especially spices, in an attempt to find cheaper alternatives with fewer side effects. Our aim is to review the relevant preclinical and clinical studies focused on the potential use of spices in the management of hypertension. Studies conducted on the most common spices, such as celery, cinnamon, cardamom, garlic, ginger, saffron, and turmeric, have been elaborated in this review. These spices may lower blood pressure via several possible mechanisms, including antioxidant effect, increase in nitric oxide production, reduction in calcium ion concentration, modulation of the renin-angiotensin pathway, etc.

The Pharmacological Activities of Crocus sativus L.: A Review Based on the Mechanisms and Therapeutic Opportunities of its Phytoconstituents

Crocus species are mainly distributed in North Africa, Southern and Central Europe, and Western Asia, used in gardens and parks as ornamental plants, while Crocus sativus L. (saffron) is the only species that is cultivated for edible purpose. The use of saffron is very ancient; besides the use as a spice, saffron has long been known also for its medical and coloring qualities. Due to its distinctive flavor and color, it is used as a spice, which imparts food preservative activity owing to its antimicrobial and antioxidant activity. This updated review discusses the biological properties of Crocus sativus L. and its phytoconstituents, their pharmacological activities, signaling pathways, and molecular targets, therefore highlighting it as a potential herbal medicine. Clinical studies regarding its pharmacologic potential in clinical therapeutics and toxicity studies were also reviewed. For this updated review, a search was performed in the PubMed, Science, and Google Scholar databases using keywords related to Crocus sativus L. and the biological properties of its phytoconstituents. From this search, only the relevant works were selected. The phytochemistry of the most important bioactive compounds in Crocus sativus L. such as crocin, crocetin, picrocrocin, and safranal and also dozens of other compounds was studied and identified by various physicochemical methods. Isolated compounds and various extracts have proven their pharmacological efficacy at the molecular level and signaling pathways both in vitro and in vivo. In addition, toxicity studies and clinical trials were analyzed. The research results highlighted the various pharmacological potentials such as antimicrobial, antioxidant, cytotoxic, cardioprotective, neuroprotective, antidepressant, hypolipidemic, and antihyperglycemic properties and protector of retinal lesions. Due to its antioxidant and antimicrobial properties, saffron has proven effective as a natural food preservative. Starting from the traditional uses for the treatment of several diseases, the bioactive compounds of Crocus sativus L. have proven their effectiveness in modern pharmacological research. However, pharmacological studies are needed in the future to identify new mechanisms of action, pharmacokinetic studies, new pharmaceutical formulations for target transport, and possible interaction with allopathic drugs.

Crocin exhibits an antihypertensive effect in a rat model of gestational hypertension and activates the Nrf-2/HO-1 signaling pathway

Gestational hypertension is a leading cause of both prenatal and maternal mortality and morbidity; however, there have been rather limited advances in the management of gestational hypertension in recent years. There has been evidence supporting the antihypertensive properties of crocin, but the specific mechanism is still unclear. N-Nitro-L-arginine methyl ester (L-NAME) was employed to establish a rat model with a preeclampsia-like phenotype, particularly gestational hypertension. Enzyme-linked immunosorbent assays were conducted to determine the levels of placental growth factor (PlGF) and soluble fms-like tyrosine kinase (sFlt-1); the levels of the circulating cytokines interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α; and oxidative stress factors. Quantitative RT-PCR assays were performed to assess the transcript levels of various cytokines in the placenta, and western blot assays were carried out to evaluate the protein levels of heme oxygenase-1 (HO-1) and nuclear factor-erythroid 2-like 2 (Nrf-2). Treatment with crocin reduced the blood pressure of rats with gestational hypertension, which was accompanied by suppressed circulating levels of PlGF and sFlt-1. Crocin further alleviated the inflammatory signals and oxidative stress in the serum, as well as in placental tissues, in rats with L-NAME-induced hypertension. Crocin treatment also improved pregnancy outcomes in terms of fetal survival, fetal weight, and the fetal/placental weight ratio. Finally, in hypertension elicited by L-NAME, crocin stimulated the placental Nrf-2/HO-1 pathway. Crocin alleviated inflammatory and oxidative stress in placental tissues, thereby protecting against gestational hypertension, one of the major phenotypes of preeclampsia, and activated the Nrf-2/HO-1 pathway.

Possible therapeutic effects of Crocus sativus stigma and its petal flavonoid, kaempferol, on respiratory disorders

CONTEXT

Crocus sativus L. (Iridaceae), or saffron, has been used as food additives and spices. In the traditional medicine of Iran, C. sativus has been used for the treatment of liver disorders, coughs, and as an anti-inflammatory agent for eyes.

OBJECTIVE

The current study reviewed the possible therapeutic effects of C. sativus stigma and its petal flavonoid (kaempferol) on respiratory disorders with several mechanisms such as anti-inflammatory, and smooth muscle relaxant effects.

MATERIALS AND METHODS

This review article searched databases including PubMed, Google Scholar, and ScienceDirect, up to November 2019. The keywords including; 'Crocus sativus', 'saffron', 'kaempferol', 'airway inflammation', and 'smooth muscle relaxant' were searched.

RESULTS

C. sativus reduced nitric oxide (NO), inducible nitric oxide synthase (iNOS) levels and inflammatory cytokines in the lung tissue. Saffron and kaempferol reduced white blood cells (WBCs) and the percentage of neutrophils and eosinophils in bronchoalveolar lavage fluid. Moreover, saffron reduced tracheal responsiveness to methacholine and ovalbumin on tracheal smooth muscles. In addition, kaempferol reduced the total leukocyte and eosinophil counts similar to the effect of dexamethasone and also showed relaxant effects on smooth muscle.

DISCUSSION AND CONCLUSION

Crocus sativus and its petal flavonoid, kaempferol, showed relatively potent therapeutic effects on respiratory disorders by relaxation of tracheal smooth muscles via stimulatory or blocking effects on β-adrenoceptor and muscarinic receptors, respectively. Saffron and kaempferol also decreased production of NO, inflammatory cytokines and chemokines in respiratory systems.

The Relaxant Effect of Crocin on Rat Tracheal Smooth Muscle and Its Possible Mechanisms

Crocin, a component of saffron, showed hypotensive activity which is perhaps due to vascular smooth muscle relaxant effect. The relaxant effects of saffron on tracheal smooth muscle also could be due to its constituent, crocin. In the present study, the relaxant effects of crocin and its possible mechanisms on rat tracheal smooth muscle were investigated. The relaxant effects of three cumulative concentrations of crocin (30, 60, and 120 μM) or theophylline (0.2, 0.4, 0.6 mM) as positive control were examined on pre-contracted tracheal smooth muscle by methacholine or KCl in non-incubated or incubated conditions with different agents including atropine, chlorpheniramine, indomethacin, diltiazem, glibenclamide, and propranolol. In non-incubated tracheal smooth muscle, crocin showed significant relaxant effects on KCl induced muscle contraction (p < 0.001 for two higher concentrations). However, crocin did not show relaxant effect on methacholine induced tissue contraction. In incubated tissues with chlorpheniramine, indomethacin, diltiazem and propranolol, there were no significant differences in the relaxant effects of crocin between non-incubated and incubated tissues. However, the relaxant effects of crocin obtained in incubated tissues with atropine and glibenclamide were significant lower than non-incubated tracheal smooth muscle (p < 0.05 to p < 0.001). The EC₅₀ value obtained in incubated tissue with propranolol was significantly increased. Theophylline showed significant relaxant effect on both KCl and methacholine induced tissue contraction (p < 0.01 to p < 0.001). A relatively potent relaxant effect of crocin on tracheal smooth muscle, lower than that of theophylline was shown. Muscarinic receptor blocking, potassium channels opening and ß₂-adrenoreceptors stimulation were also suggested as possible mechanisms of this effect.

Impact of Crocus Sativus L. on Metabolic Profile in Patients with Diabetes Mellitus or Metabolic Syndrome: A Systematic Review

Background: Experimental studies demonstrated a positive effect of administration of Crocus sativus L. (saffron) and its bioactive ingredients on metabolic profile through their antioxidant capacity. Purpose: To determine if the use of saffron in humans is beneficial to patients with diabetes mellitus (DM) or metabolic syndrome (MS). Methods: This systematic review includes 14 randomized control trials that investigated the impact of saffron administration and its bioactive ingredient crocin on the metabolic profile of patients with DM, MS, prediabetes, and coronary artery disease. We documented the following clinical outcomes: fasting blood glucose (FBG), glycated haemoglobin (HbA1c), total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides, systolic, and diastolic blood pressure. Results: Eight studies examined the efficacy of saffron in patients with DM, four with the metabolic syndrome, one with prediabetes and one with coronary artery disease. A favorable effect on FBG was observed. The results regarding blood lipids and blood pressure were inconclusive in the current review. Conclusions: According to the available limited evidence, saffron may have a favorable effect on FBG. Many of the studies in the reviewed literature are of poor quality, and more research is needed in this direction to confirm and establish the above findings.

Anti-hypertensive effect of crocin and hesperidin combination in high-fat diet treated rats

Cardiovascular diseases are the leading cause of death worldwide. Hypertension is the most important cause of such conditions. The use of medicinal herbs is of particular importance due to their lower cost and side effects. The aim of the present study was to compare the effect of hesperidin (HES) and crocin (CRO) alone and in combination, on blood pressure in a rat model of high-fat diet (HFD)-induced hypertension, using invasive carotid artery measurements. Animals were randomly assigned to the following groups: control group (received standard chow diet), HFD control group (received HFD containing 32% kcal of fat and 0.1% cholesterol), and three groups of HFD-treated animals that were treated with a single dose of CRO (20 mg/kg), HES (20 mg/kg), or CRO + HES (20 + 20 mg/kg). Except for the control group, rats received HFD for 7 weeks. On day 50, CRO, HES and normal saline were administered intraperitoneally and carotid arteries of the rats were cannulated. Three hours after the carotid artery cannulation, mean arterial blood pressure (MAP), systolic and diastolic blood pressure (SBP and DBP), and heart rate (HR) were measured using an intra-arterial catheter with the use of a Power Lab system. Data was analyzed using SPSS software. Rats that received HFD for 49 days presented a significant increase in SBP, HR and MAP compared to the control group (P<0.001). Whereas, HFD-treated rats of the CRO + HES group showed lower levels of SBP, HR and MAP; however, DBP remained unaffected. HES administration in HFD treated rats resulted in a significant decrease in SBP compared to the HFD control group with no significant differences in MAP. The hypotensive effects of the simultaneous administration of CRO and HES in HFD-hypertensive rats suggest the need for further study of these two natural products as a potential preventive measure against hypertension development, especially in patients with high normal blood pressure.

Turmeric, Pepper, Cinnamon, and Saffron Consumption and Mortality

Background Previous studies have reported the beneficial effects of spice consumption on lipid profiles, fasting glucose, and blood pressure, which suggests that spice consumption could affect the risk of cardiovascular disease, diabetes mellitus, and consequently mortality. The objective of this study was to evaluate the relationship between consumption of turmeric, black or chili pepper, cinnamon, and saffron with overall and cause-specific mortality in an adult population in Iran. Methods and Results We used data from the Golestan Cohort Study, which has followed 50 045 participants aged 40 to 75 years from baseline (2004-2008). After establishing the exclusion criteria, 44 398 participants were included in the analyses. Spice consumption data were extracted from the baseline Food Frequency Questionnaire. Cox models were used to estimate hazard ratios (HR) and 95% CI for overall and cause-specific mortality, comparing the ever consumers to the never consumers as a reference group for each type of spice (adjusted for known and suspected confounders). During 11 years of follow-up, 5121 people died. Turmeric consumption was associated with significantly reduced risk of overall mortality (HR=0.90, 95% CI=0.85-0.96) and cardiovascular mortality (HR=0.91, 95% CI=0.82-0.99). Black or chili pepper consumption was associated with significantly reduced risk of overall mortality (HR=0.91, 95% CI=0.86-0.98). Saffron consumption was associated with significantly reduced risk of overall (HR=0.85, 95% CI=0.77-0.94) and cardiovascular mortality (HR=0.79, 95% CI=0.68-0.92). We found no associations with cinnamon consumption or between any of these spices and cancer mortality. Conclusions Consuming turmeric or saffron was associated with decreased risk of overall and cardiovascular mortality. The hypothesis of a protective effect of spice consumption on mortality should be tested in other prospective studies.

Antioxidant Properties of Crocus Sativus L. and Its Constituents and Relevance to Neurodegenerative Diseases; Focus on Alzheimer's and Parkinson's Disease

BACKGROUND

Reactive oxygen species and reactive nitrogen species, which are collectively called reactive oxygen-nitrogen species, are the inevitable by-products of cellular metabolic redox reactions, such as oxidative phosphorylation in the mitochondrial respiratory chain, phagocytosis, reactions of biotransformation of exogenous and endogenous substrata in endoplasmic reticulum, eicosanoid synthesis, and redox reactions in the presence of metal with variable valence. Among medicinal plants, there is growing interest in Crocus Sativus L. It is a perennial, stemless herb, belonging to Iridaceae family, cultivated in various countries such as Greece, Italy, Spain, Israel, Morocco, Turkey, Iran, India, China, Egypt and Mexico.

OBJECTIVE

The present study aims to address the protective role of Crocus Sativus L. in neurodegeneration with an emphasis in Parkinson's and Alzheimer's disease.

MATERIALS AND METHODS

An electronic literature search was conducted by two of the authors from 1993 to August 2017. Original articles and systematic reviews (with or without meta-analysis), as well as case reports were selected. Titles and abstracts of papers were screened by a third reviewer to determine whether they met the eligibility criteria, and full texts of the selected articles were retrieved.

RESULTS

Hence, the authors focused on the literature concerning the role of Crocus Sativus L. on its anti-oxidant and neuroprotective properties.

CONCLUSION

Literature findings represented in current review herald promising results for using Crocus Sativus L. and/or its active constituents as antioxidants, anti-inflammatory, and neuroprotective agents.

The Protective Role of Crocus Sativus L. (Saffron) Against Ischemia- Reperfusion Injury, Hyperlipidemia and Atherosclerosis: Nature Opposing Cardiovascular Diseases

Background:

Reactive oxygen species and reactive nitrogen species, which are collective-ly called reactive oxygen-nitrogen species, are inevitable by-products of cellular metabolic redox reac-tions, such as oxidative phosphorylation in the mitochondrial respiratory chain, phagocytosis, reac-tions of biotransformation of exogenous and endogenous substrate in endoplasmic reticulum, eico-sanoid synthesis, and redox reactions in the presence of metal with variable valence. Among medici-nal plants, there is growing interest in Crocus Sativus L. It is a perennial, stemless herb, belonging to Iridaceae family, cultivated in various countries such as Greece, Italy, Spain, Israel, Morocco, Tur-key, Iran, India, China, Egypt and Mexico.

Objective:

The present study aims to address the anti-toxicant role of Crocus Sativus L. in the case of cardiovascular disease and its role towards the cardioprotective role of Crocus Sativus L.

Materials and

Methods:

An electronic literature search was conducted by the two authors from 1993 to August 2017. Original articles and systematic reviews (with or without meta-analysis), as well as case reports were selected. Titles and abstracts of papers were screened by a third reviewer to deter-mine whether they met the eligibility criteria, and full texts of the selected articles were retrieved.

Results:

Our review has indicated that scientific literature confirms the role of Crocus Sativus L. as a cardiovascular-protective agent. The literature review showed that Saffron is a potent cardiovascular-protective agent with a plethora of applications ranging from ischemia-reperfusion injury, diabetes and hypertension to hyperlipidemia.

Conclusion:

Literature findings represented in current review herald promising results for using Crocus Sativus L. and/or its active constituents as a cardiovascular-protective agent and in particular, Crocus Sativus L. manifests beneficial results against ischemia-reperfusion injury, hypertension, hy-perlipidemia and diabetes

The effect of saffron (Crocus sativus L.) hydroalcoholic extract on metabolic control in type 2 diabetes mellitus: A triple-blinded randomized clinical trial

Background:

Metabolic control is a major concern in preventing diabetic complications. Saffron as a natural source of antioxidants could play a role in alleviating diabetes insults. The aim of this study was to investigate effect of saffron hydroalcoholic extract on metabolic control in type 2 diabetes (T2D) mellitus.

Materials and Methods:

This randomized triple blind study was included 54 T2D patients which randomly received either saffron (Group 1) or placebo (Group 2) twice daily other than routine antidiabetic treatments for 8 weeks. Serum concentration of fasting blood sugar (FBS), 2-h plasma glucose, hemoglobin A1c (HbA1c), total cholesterol, triglyceride (TG), low-density lipoprotein, and high-density lipoprotein were measured as the markers of metabolic control. Anthropometric measures and blood pressure were also measured at the baseline, every 2 weeks during the intervention and the end of the study. Data analyzed using repeated measure analysis of variance test.

Results:

The baseline metabolic parameters were the same in two group (P > 0.01). FBS serum level significantly decreased within 8 weeks in the saffron group (128.84 ± 31.86) as compared to the placebo (153.76 ± 41.23), (P < 0.001). There was no statistical difference in other metabolic parameters such as serum lipids, blood pressure, and HbA1c (P > 0.01).

Conclusion:

Saffron hydroalcoholic extract may improve blood glucose control by reducing FBS in T2D patients. However, saffron extract has no significant effect on other aspects of diabetic control in diabetic patients.

Saffron Induced Relaxation in Isolated Rat Aorta via Endothelium Dependent and Independent Mechanisms

Crocus sativus L. (saffron) is a widely used food additive for its color and taste. The hypotensive effects of saffron have been shown in previous studies. The aim of this study was to evaluate the mechanism of vasodilatory effects induced by saffron on isolated rat aorta. To study the vasodilatory effects of saffron aqueous extract (0.5, 1 and 2 mg/mL), isolated rat thoracic aorta rings were contracted by 10^-6 M phenylephrine (PE) or KCl 80 mM. The vasodilatory effect of saffron was also evaluated both on intact and denuded endothelium aortic rings. To study the role of nitric oxide and prostacyclin in relaxation induced by saffron, aortic rings were incubated by L-NAME (10^-6 M) and indomethacin (10^-5 M) respectively for 20 min. Saffron induced relaxation in endothelium-intact aortic rings precontracted with PE in a concentration dependent manner. The obtained relaxation induced by the highest saffron concentration in endothelium-intact aortic rings precontracted with KCl was less than that observed in endothelium-intact aortic rings precontracted with PE. The relaxant activity of saffron was abolished by incubation of aortic rings with L-NAME but not in the presence of indomethacin. Also, the vasodilatory activity of saffron was partially abolished in endothelium denuded aortic rings. Saffron induced relaxation in isolated rat aortic rings might be due particularly to its effect on endothelium via nitric oxide synthase pathway and partly due to the effect on vascular smooth muscle cells via L type voltage dependent calcium channels.

Saffron against Components of Metabolic Syndrome: Current Status and Prospective

Saffron, the dried stigmas of Crocus sativus L., is mainly used as a food coloring and flavoring agent. This agricultural product is used in traditional medicine for the treatment of several diseases including asthma, liver disease, menstruation disorders, and, of special interest in this review, metabolic syndrome. Saffron and its active components including crocin, crocetin, and safranal are potential therapeutic candidates for attenuating MetS complications including hypertension, hyperglycemia, obesity, and dyslipidemia. This review summarizes the protective role of saffron and its constituents in the pathogenesis of MetS for a better understanding and hence a better management of this disease.

Saffron: a promising natural medicine in the treatment of metabolic syndrome

Metabolic syndrome is a disorder which encompasses obesity, high blood glucose, high cholesterol levels and high blood pressure. Moreover, metabolic syndrome is considered as the most important risk factor for cardiovascular disease (CVD). CVD is the leading cause of mortality in the world for both men and women. Several chemical drugs are available to treat metabolic risk factors, but because of the safety, efficacy, cultural acceptability and lesser side effects, nowadays herbal therapy has a critical role in the treatment of these CVD risk factors. Crocus sativus L. (saffron) is a perennial herb that belongs to the Iridaceae family. Saffron is an extensively used food additive for its colour and taste and has been widely used in traditional as well as modern medicine to treat several illnesses including cardiovascular diseases. Most of the unique properties of this plant are attributed to the presence of three major components, including crocin, safranal and crocetin. It has been proved that saffron has an important role in the management of metabolic syndrome because of its marvelous activities including anti-diabetic, anti-obesity, hypotensive and hypolipidaemic properties. In this review article, we discuss the beneficial properties of saffron and its active components to treat different components of metabolic syndrome and most relevant animal and human studies regarding the use of this plant in cardiovascular disease, with focus on the metabolic risk factors. This review also suggests that after randomised clinical trials, saffron may be implicated as a preventive or therapeutic agent against metabolic syndrome. © 2016 Society of Chemical Industry.

Possible Role of Common Spices as a Preventive and Therapeutic Agent for Alzheimer's Disease

For centuries, spices have been consumed as food additives or medicinal agents. However, there is increasing evidence indicating the plant-based foods in regular diet may lower the risk of neurodegenerative diseases including Alzheimer disease. Spices, as one of the most commonly used plant-based food additives may provide more than just flavors, but as agents that may prevent or even halt neurodegenerative processes associated with aging. In this article, we review the role and application of five commonly used dietary spices including saffron turmeric, pepper family, zingiber, and cinnamon. Besides suppressing inflammatory pathways, these spices may act as antioxidant and inhibit acetyl cholinesterase and amyloid β aggregation. We summarized how spice-derived nutraceuticals mediate such different effects and what their molecular targets might be. Finally, some directions for future research are briefly discussed.

Saffron with resistance exercise improves diabetic parameters through the GLUT4/AMPK pathway in-vitro and in-vivo

Saffron is consumed as food and medicine to treat several illnesses. This study elucidates the saffron effectiveness on diabetic parameters in-vitro and combined with resistance exercise in-vivo. The antioxidant properties of saffron was examined. Insulin secretion and glucose uptake were examined by cultured RIN-5F and L6 myotubes cells. The expressions of GLUT2, GLUT4, and AMPKα were determined by Western blot. Diabetic and non-diabetic male rats were divided into: control, training, extract treatment, training + extract treatment and metformin. The exercise and 40 mg/kg/day saffron treatments were carried out for six weeks. The antioxidant capacity of saffron was higher compare to positive control (P < 0.01). High dose of saffron stimulated insulin release in RIN-5F cells and improved glucose uptake in L6 myotubes. GLUT4 and AMPKα expressions increased in both doses of saffron (P < 0.01), whereas GLUT2 not changed (p > 0.05). Serum glucose, cholesterol, triglyceride, low-density lipoprotein, very low-density lipoprotein, insulin resistance, and glycated hemoglobin levels decreased in treated rats compared to untreated (p < 0.01). However, no significant differences were observed in the high-density lipoprotein, insulin, adiponectin, and leptin concentration levels in all groups (p > 0.05). The findings suggest that saffron consuming alongside exercise could improve diabetic parameters through redox-mediated mechanisms and GLUT4/AMPK pathway to entrap glucose uptake.

Dietary saffron reduced the blood pressure and prevented remodeling of the aorta in L-NAME-induced hypertensive rats

OBJECTIVES

The aim of this study was to investigate the effects of nutritional saffron (Crocus sativus L.) stigma hydroalcoholic extract on blood pressure (BP) and histology of the aorta in normotensive and hypertensive rats.

MATERIALS AND METHODS

Saffron (200 mg/kg/day) was given orally for 5 weeks to normotensive and hypertensive rats. Hypertension was induced by NG-nitro-L-arginine methyl ester (L-NAME; 40 mg/kg/day) administration in drinking water, and BP was measured weekly. Histological examination of the thoracic aorta included staining with hematoxylin and eosin, orcein, and periodic acid Schiff methods.

RESULTS

Saffron had no effect on normotensive rats, but on hypertensive rats, prevented BP elevation form the third week of treatment (P<0.001). Furthermore, saffron reduced the cross-section area, media thickness, and elastic lamellae number of the aorta (P<0.05).

CONCLUSION

Nutritional saffron prevented BP increases and remodeling of the aorta in hypertensive rats. It may be useful for preventing hypertension.

Effects of Crocetin Esters and Crocetin from Crocus sativus L. on Aortic Contractility in Rat Genetic Hypertension

Background: Endothelial dysfunction, characterized by an enhancement in vasoconstriction, is clearly associated with hypertension. Saffron (Crocus sativus L.) bioactive compounds have been recognized to have hypotensive properties. Recently, we have reported that crocetin exhibits potent vasodilator effects on isolated aortic rings from hypertensive rats. In this work, we have aimed to analyze the anticontractile ability of crocetin or crocetin esters pool (crocins) isolated from saffron. Thus, we have studied the effects of saffron carotenoids on endothelium-dependent and -independent regulation of smooth muscle contractility in genetic hypertension. Methods: We have measured the isometric responses of aortic segments with or without endothelium obtained from spontaneously hypertensive rats. The effects of carotenoids were studied by assessing the endothelial modulation of phenylephrine-induced contractions (10⁻⁹–10⁻⁵ M) in the presence or absence of crocetin or crocins. The role of nitric oxide and prostanoids was analyzed by performing the experiments with L-NAME (NG-nitro-l-arginine methyl ester) or indomethacin (both 10⁻⁵ M), respectively. Results: Crocetin, and to a minor extent crocins, diminished the maximum contractility of phenylephrine in intact rings, while crocins, but not crocetin, increased this contractility in de-endothelizated vessels. In the intact vessels, the effect of crocetin on contractility was unaffected by indomethacin but was abolished by L-NAME. However, crocetin but not crocins, lowered the already increased contractility caused by L-NAME. Conclusions: Saffron compounds, but especially crocetin have endothelium-dependent prorelaxing actions. Crocins have procontractile actions that take place via smooth muscle cell mechanisms. These results suggest that crocetin and crocins activate different mechanisms involved in the vasoconstriction pathway in hypertension.

Saffron as an antidote or a protective agent against natural or chemical toxicities

Saffron (Crocus sativus) is an extensively used food additive for its color and taste. Since ancient times this plant has been introduced as a marvelous medicine throughout the world. The wide spectrum of saffron pharmacological activities is related to its major constituents including crocin, crocetin and safranal. Based on several studies, saffron and its active ingredients have been used as an antioxidant, antiinflammatory and antinociceptive, antidepressant, antitussive, anticonvulsant, memory enhancer, hypotensive and anticancer. According to the literatures, saffron has remarkable therapeutic effects. The protective effects of saffron and its main constituents in different tissues including brain, heart, liver, kidney and lung have been reported against some toxic materials either natural or chemical toxins in animal studies.

In this review article, we have summarized different in vitro and animal studies in scientific databases which investigate the antidotal and protective effects of saffron and its major components against natural toxins and chemical-induced toxicities. Due to the lake of human studies, further investigations are required to ascertain the efficacy of saffron as an antidote or a protective agent in human intoxication.

Smooth muscle relaxant activity of Crocus sativus (saffron) and its constituents: possible mechanisms

Saffron, Crocus sativus L. (C. sativus) is rich in carotenoids and used in traditional medicine for treatment of various conditions such as coughs, stomach disorders, amenorrhea, asthma and cardiovascular disorders. These therapeutic effects of the plant are suggested to be due to its relaxant effect on smooth muscles. The effect of C. sativus and its constituents on different smooth muscles and the underlying mechanisms have been studied. Several studies have shown the relaxant effects of C. sativus and its constituents including safranal, crocin, crocetin and kaempferol on blood vessels. In addition, it was reported that saffron stigma lowers systolic blood pressure. The present review highlights the relaxant effects of C. sativus and its constituents on various smooth muscles. The possible mechanisms of this relaxing effect including activation of ß2-adrenoceptors, inhibition of histamine H1 and muscarinic receptors and calcium channels and modulation of nitric oxide (NO) are also reviewed.

Safety evaluation of saffron stigma (Crocus sativus L.) aqueous extract and crocin in patients with schizophrenia

OBJECTIVES

Saffron is the stigma of Crocus sativus L., which has the potentials to play a role in the treatment of many diseases. Although many researches are now going on this precious spice, there are few data on saffron safety in human, especially in patients with chronic mental illnesses. This study aimed to evaluate the short-term safety and tolerability of both saffron and crocin (its major constituent) in adult patients with schizophrenia.

MATERIALS AND METHODS

The capsules of saffron aqueous extract (SAE) and crocin were used to evaluate short-term safety and tolerability in patients with schizophrenia. A double-blind, placebo-controlled study was performed on patients with schizophrenia. The patients were all male and were divided into three 22-patient groups. While receiving their normal treatment, they also received a 12 week treatment with SAE (15 mg twice daily), crocin (15 mg twice daily) or placebo.

RESULTS

A total of 61 patients completed the trial; none of them reported a serious side effect. WBC count increased significantly in patients receiving saffron aqua extract (SAE), but it was within the normal range and had no clinical significance. Other hematologic components, markers of thyroid, liver and kidney or inflammation markers had no statistically significant difference among the groups.

CONCLUSION

This study showed that SAE and crocin in doses of 15 mg twice daily were safely tolerated in patients with schizophrenia.