The GABAA-Benzodiazepine Receptor Antagonist Flumazenil Abolishes the Anxiolytic Effects of the Active Constituents of Crocus sativus L. Crocins in Rats.

Anxiety is a chronic severe psychiatric disorder. Crocins are among the various bioactive components of the plant Crocus sativus L. (Iridaceae) and their implication in anxiety is well-documented. However, which is the mechanism of action underlying the anti-anxiety effects of crocins remains unknown. In this context, it has been suggested that these beneficial effects might be ascribed to the agonistic properties of these bioactive ingredients of saffron on the GABA type A receptor. The current experimentation was undertaken to clarify this issue in the rat. For this research project, the light/dark and the open field tests were used. A single injection of crocins (50 mg/kg, i.p., 60 min before testing) induces an anti-anxiety-like effect revealed either in the light-dark or open field tests. Acute administration of the GABAA-benzodiazepine receptor antagonist flumazenil (10 mg/kg, i.p., 30 min before testing) abolished the above mentioned anxiolytic effects of crocins. The current findings suggest a functional interaction between crocins and the GABAA receptor allosteric modulator flumazenil on anxiety.

Characterization and assessment of the genotoxicity and biocompatibility of poly (hydroxybutyrate) and norbixin membranes.

Purpose To synthesize and characterize poly(hydroxybutyrate) (PHB) and norbixin membranes to evaluate them for genotoxicity in rats and wound healing in mice by histological staining. Methods For the evaluation of genotoxicity, male rats ( Rattus novegicus ) were divided into three groups (n= 5): 5% PHB/Norbixin membrane introduced into the peritoneum by laparotomy; B - negative control; C - positive control (intraperitoneal dose of cyclophosphamide 50 mg/kg). For the evaluation of biocompatibilty, a cutaneous wound was induced on the back of males mice ( Mus musculus ) divided into two experimental treatment groups: control and membrane that underwent euthanasia after 7 and 14 days treatment. Statistical analysis ware made by One Way Anova post hoc Tukey Test (p<0.05). Results Regarding the incidence of polychromatic erythrocytes, there was no difference between negative control and 5% PHB/Norbixin membrane; however, when compared to the positive control represented by cyclophosphamide, there was a significant difference (p <0.001). As for DNA damage, the changes induced in the first 4h were repaired in 24h. In addition, the membrane was effective in abbreviating the inflammatory process and served as a scaffold due to the stimulus to reepithelialization mainly on the 7 days of treatment. Conclusion The non-genotoxic PHB/Norbixin 5% membrane presented promising results that suggest its effectiveness as a guide for tissue regeneration given its biocompatibility.

Characterization and assessment of the genotoxicity and biocompatibility of poly (hydroxybutyrate) and norbixin membranes

Abstract Purpose To synthesize and characterize poly(hydroxybutyrate) (PHB) and norbixin membranes to evaluate them for genotoxicity in rats and wound healing in mice by histological staining. Methods For the evaluation of genotoxicity, male rats ( Rattus novegicus ) were divided into three groups (n= 5): 5% PHB/Norbixin membrane introduced into the peritoneum by laparotomy; B - negative control; C - positive control (intraperitoneal dose of cyclophosphamide 50 mg/kg). For the evaluation of biocompatibilty, a cutaneous wound was induced on the back of males mice ( Mus musculus ) divided into two experimental treatment groups: control and membrane that underwent euthanasia after 7 and 14 days treatment. Statistical analysis ware made by One Way Anova post hoc Tukey Test (p<0.05). Results Regarding the incidence of polychromatic erythrocytes, there was no difference between negative control and 5% PHB/Norbixin membrane; however, when compared to the positive control represented by cyclophosphamide, there was a significant difference (p <0.001). As for DNA damage, the changes induced in the first 4h were repaired in 24h. In addition, the membrane was effective in abbreviating the inflammatory process and served as a scaffold due to the stimulus to reepithelialization mainly on the 7 days of treatment. Conclusion The non-genotoxic PHB/Norbixin 5% membrane presented promising results that suggest its effectiveness as a guide for tissue regeneration given its biocompatibility.

A comprehensive review on biological activities and toxicology of crocetin.

Natural products with high pharmacological potential and low toxicity have been considered as the novel therapeutic agents. Crocetin is an active constituent of saffron (Crocus sativus L.) stigma, which in its free-acid form is insoluble in water and most organic solvents. Crocetin exhibits various health-promoting properties including anti-tumor, neuroprotective effects, anti-diabetics, anti-inflammatory, anti-hyperlipidemia, etc. These therapeutic effects can be achieved with different mechanisms such as improvement of oxygenation in hypoxic tissues, antioxidant effects, inhibition of pro-inflammatory mediators, anti-proliferative activity and stimulation of apoptosis in cancer cells. It is also worth considering that crocetin could be tolerated without major toxicity at therapeutic dosage in experimental models. In the present review, we discuss the biosynthesis, pharmacokinetic properties of crocetin and provide a comprehensive study on the biological activities and toxicity along with the mechanism of actions and clinical trials data of crocetin.

Exploring the Valuable Carotenoids for the Large-Scale Production by Marine Microorganisms.

Carotenoids are among the most abundant natural pigments available in nature. These pigments have received considerable attention because of their biotechnological applications and, more importantly, due to their potential beneficial uses in human healthcare, food processing, pharmaceuticals and cosmetics. These bioactive compounds are in high demand throughout the world; Europe and the USA are the markets where the demand for carotenoids is the highest. The in vitro synthesis of carotenoids has sustained their large-scale production so far. However, the emerging modern standards for a healthy lifestyle and environment-friendly practices have given rise to a search for natural biocompounds as alternatives to synthetic ones. Therefore, nowadays, biomass (vegetables, fruits, yeast and microorganisms) is being used to obtain naturally-available carotenoids with high antioxidant capacity and strong color, on a large scale. This is an alternative to the in vitro synthesis of carotenoids, which is expensive and generates a large number of residues, and the compounds synthesized are sometimes not active biologically. In this context, marine biomass has recently emerged as a natural source for both common and uncommon valuable carotenoids. Besides, the cultivation of marine microorganisms, as well as the downstream processes, which are used to isolate the carotenoids from these microorganisms, offer several advantages over the other approaches that have been explored previously. This review summarizes the general properties of the most-abundant carotenoids produced by marine microorganisms, focusing on the genuine/rare carotenoids that exhibit interesting features useful for potential applications in biotechnology, pharmaceuticals, cosmetics and medicine.

Anticancer activity of crocin against cervical carcinoma (HeLa cells): Bioassessment and toxicity evaluation of crocin in male albino rats.

The present study was aimed to investigate anticancer activity of crocin against cervical carcinoma and bio-assessment and toxicological evaluation in male albino rats. Effect of crocin on cell viability (anticancer activity) was determined against cervical carcinoma cells. Chronic effect of crocin on body weight changes, serum enzymes, serum biochemical markers, lipid peroxidation, hematological markers and DNA damage in male albino rats were determined. Cell survival rate was reduced 98.4, 95.7, 87.2, 81.1 and 73.1% at 25, 50, 75, 100 and 125 mg/l of crocin respectively. Cell viability was reduced 97.1, 96.4, 85.5, 78.4 and 70.2% at 25, 50, 75, 100 and 125 mg/l of crocin respectively. Crocin reduced body weight significantly at 30 and 60th day. Alanine transaminase (ALT), aspartate transaminase (AST), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), blood urea nitrogen (BUN), creatinine, bilirubin, albumin and total protein were decreased, while glucose, cholesterol, TG, and GSH were increased. Hemoglobin (Hb), white blood cells (WBC), lymphocytes, neutrophil and packed cell volume (PCV) were altered following crocin treatment. Necrosis, fibrosis, mononuclear infiltration, angiogenesis and DNA fragmentation were also noted. Taking all these data together, it is suggested that the crocin could be a potential antitumor agent against cervical carcinoma. However, the altered histological, biochemical and hematological markers may lead to an adverse effect on the cellular metabolism and physiological activity.

Safety Assessment of Oil from Pequi (Caryocar brasiliense Camb.): Evaluation of the Potential Genotoxic and Clastogenic Effects.

Genotoxic data of medicinal plants and functional foods are required as part of the risk assessment by international regulatory agencies. Due to its food consumption and ethnopharmacological relevance, pequi oil (Caryocar brasiliense Camb.) is one of these compounds to be studied. The aim of this study was to evaluate the cytotoxic, genotoxic, and clastogenic effects of the oil from the pulp of C. brasiliense (OPCB) in vivo and in vitro. Initially, the Artemia salina in vitro assay was conducted to determine the cells viability rate of different doses of the OPCB. Subsequently, comet assay (Organization for Economic Cooperation and Development, OECD 489) and micronucleus test (OECD 474) were performed in blood and bone marrow of Wistar rats treated orally with a 125, 250, 500, or 1000 mg/kg/bw of the OPCB for 4 weeks. The chemical analysis indicated the presence of ß-carotene and lycopene in the oil. In the A. salina test, all OPCB doses maintained cell viability rates statistically similar to the negative control. The in vivo tests performed showed that OPCB did not show significant genotoxic or clastogenic effects in cells analyzed with the four doses tested. Altogether, these results indicate that, under our experimental conditions, C. brasiliense fruit oil did not reveal genetic toxicity in rat cells.

Carotenoid glycosides from cyanobacteria are teratogenic in the zebrafish (Danio rerio) embryo model.

Toxigenicity of cyanobacteria is widely associated with production of several well-described toxins that pose recognized threats to human and ecosystem health as part of both freshwater eutrophication, and episodic blooms in freshwater and coastal habitats. However, a preponderance of evidence indicates contribution of additional bioactive, and potentially toxic, metabolites. In the present study, the zebrafish (Danio rerio) embryo was used as a model of vertebrate development to identify, and subsequently isolate and characterize, teratogenic metabolites from two representative strains of C. raciborskii. Using this approach, three chemically related carotenoids - and specifically the xanthophyll glycosides, myxol 2'-glycoside (1), 4-ketomyxol 2'-glycoside (2) and 4-hydroxymyxol 2'-glycoside (3) - which are, otherwise, well known pigment molecules from cyanobacteria were isolated as potently teratogenic compounds. Carotenoids are recognized "pro-retinoids" with retinoic acid, as a metabolic product of the oxidative cleavage of carotenoids, established as both key mediator of embryo development and, consequently, a potent teratogen. Accordingly, a comparative toxicological study of chemically diverse carotenoids, as well as apocarotenoids and retinoids, was undertaken. Based on this, a working model of the developmental toxicity of carotenoids as pro-retinoids is proposed, and the teratogenicity of these widespread metabolites is discussed in relation to possible impacts on aquatic vertebrate populations.

Evaluation of Cytotoxic Effect and Antioxidant Activity of Grape Seed Extract, Crocin, and Phenytoin.

Antioxidant compounds inhibit formation of free radicals, chelate catalytic metals, and scavenge free radicals in biological systems. In addition, antioxidants play a decisive role in prevention of numerous physiological dysfunctions, cancers, and metabolic disorders. This study sought to evaluate the antioxidant capacity and cytotoxic effect of grape seed extract (GSE), crocin (CRO), and phenytoin (PHEN) on a human breast cancer cell line (MCF-7). Methanol extracts of the three mentioned agents were prepared and their antioxidant activity was evaluated by diphenyl-1-picrylhydrazyl method, using Quercetine (QUER) as positive control. The 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to evaluate the cytotoxic effect of the extracts on Michigan Cancer Foundation-7MCF-7 cell line, using doxorubicin hydrochloride (DOX) as the positive control. Given the results, greater scavenging activity was achieved by using GSE in comparison to CRO and PHEN. Further, a significant correlation was found between the antioxidant activity and cytotoxic effects of these agents, and GSE had the highest antioxidant capacity and cytotoxic effect in comparison to CRO and PHEN.

Prooxidant activity of norbixin in model of acute gastric ulcer induced by ethanol in rats.

Free radicals and oxidative stress play a central role in gastric injuries caused by ethanol (EtOH). Antioxidant strategies to counteract EtOH toxicity are highly desirable. Norbixin (NBIX) is a carotenoid with antioxidant potential largely used in the food industry. This study evaluated the NBIX effects in a model of gastric ulcer induced by EtOH in rats. Male Wistar rats received NBIX doses of 0, 10, and 25 mg/kg by gavage 1 h after EtOH administration (0 or 75% solution, 1 mL/200 g of animal). The animals were euthanized 1 h after the NBIX administration, and their stomachs were removed for macroscopic and histopathological analyses, quantification of nonprotein sulfhydryl (NPSH) groups, lipid peroxidation (LPO) levels, and catalase (CAT) activity determination. NBIX increased LPO in gastric mucosa and caused CAT inhibition and NPSH depletion in EtOH-treated animals. Results showed that NBIX did not protect gastric tissue against EtOH damage, and this could be associated to a prooxidant effect.

Natural Origin Lycopene and Its "Green" Downstream Processing.

Lycopene is an abundant natural carotenoid pigment with several biological functions (well-known for its antioxidant properties) which is under intensive investigation in recent years. Lycopene chemistry, its natural distribution, bioavailability, biological significance, and toxicological effects are briefly outlined in the first part of this review. The second, major part, deals with various modern downstream processing techniques, which are assessed in order to identify promising approaches for the recovery of lycopene and of similar lipophilic compounds. Natural lycopene is synthesized in plants and by microorganisms, with main representatives of these two categories (for industrial production) tomato and its by-products and the fungus Blakeslea trispora, respectively. Currently, there is a great deal of effort to develop efficient downstream processing for large scale production of natural-origin lycopene, with trends strongly indicating the necessity for "green" and mild extraction conditions. In this review, emphasis is placed on final product safety and ecofriendly processing, which are expected to totally dominate in the field of natural-origin lycopene extraction and purification.

Evaluation of teratogenic effects of crocin and safranal, active ingredients of saffron, in mice.

Saffron (Crocus sativus) is a widely used food additive for its color and taste. Crocin and safranal are two main components of this plant. Numerous studies are underway to introduce saffron and its active ingredients as pharmacological agents. Safety assessments of these compounds are important parts of this endeavor. In this study, the effects of crocin and safranal administrations during embryogenesis have been investigated in mice. A total of 75 BALB/c pregnant mice were divided into six experimental and control groups. Four experimental groups received intraperitoneal injection of crocin (200 mg/kg or 600 mg/kg) daily or safranal (0.075 ml/kg or 0.225 ml/kg) on gestational days (GDs) 6 to 15. Control groups received normal saline or paraffin as solvents of crocin and safranal. Dams were dissected on GD18 and embryos were collected. Routine maternal and fetal parameters were recorded. Macroscopic observation of external malformations was also performed. Fetuses were then selected for double skeletal staining with alizarin red and alcian blue. All experimental groups caused significant decrease in length and weight of fetuses when compared with the control groups and revealed malformations such as minor skeletal malformations, mandible and calvaria malformations, and growth retardation. Minor skeletal malformations were the most commonly observed abnormality, which were statistically significant when compared with the control groups (p < 0.05). The severities of malformations were comparable in the crocin- and safranal-treated groups. This study suggests that crocin or safranal can induce embryonic malformations when administered in pregnant mice. Due to the wide use of saffron, further elaborate studies to understand the malformation mechanisms of these ingredients are recommended.

The first evidence of deinoxanthin from Deinococcus sp. Y35 with strong algicidal effect on the toxic dinoflagellate Alexandrium tamarense.

Harmful algal blooms (HABs) could be deemed hazardous materials in aquatic environment. Alexandrium tamarense is a toxic HAB causing alga, which causes serious economic losses and health problems. In this study, the bacterium Deinococcus xianganensis Y35 produced a new algicide, showing a high algicidal effect on A. tamarense. The algicidal compound was identified as deinoxanthin, a red pigment, based on high resolution mass spectrometry and NMR after the active compound was isolated and purified. Deinoxanthin exhibited an obvious inhibitory effect on algal growth, and showed algicidal activity against A. tamarense with an EC50 of 5.636 µg/mL with 12h treatment time. Based on the unique structure and characteristics of deinoxanthin, the content of reactive oxygen species (ROS) increased after 0.5h exposure, the structure of organelles including chloroplasts and mitochondria were seriously damaged. All these results firstly confirmed that deinoxanthin as the efficient and eco-environmental algicidal compound has potential to be used for controlling harmful algal blooms through overproduction of ROS.

Defective autophagosome formation in p53-null colorectal cancer reinforces crocin-induced apoptosis.

Crocin, a bioactive molecule of saffron, inhibited proliferation of both HCT116 wild-type and HCT116 p53(-/-) cell lines at a concentration of 10 mM. Flow cytometric analysis of cell cycle distribution revealed that there was an accumulation of HCT116 wild-type cells in G1 (55.9%, 56.1%) compared to the control (30.4%) after 24 and 48 h of crocin treatment, respectively. However, crocin induced only mild G2 arrest in HCT116 p53(-/-) after 24 h. Crocin induced inefficient autophagy in HCT116 p53(-/-) cells, where crocin induced the formation of LC3-II, which was combined with a decrease in the protein levels of Beclin 1 and Atg7 and no clear p62 degradation. Autophagosome formation was not detected in HCT116 p53(-/-) after crocin treatment predicting a nonfunctional autophagosome formation. There was a significant increase of p62 after treating the cells with Bafilomycin A1 (Baf) and crocin compared to crocin exposure alone. Annexin V staining showed that Baf-pretreatment enhanced the induction of apoptosis in HCT116 wild-type cells. Baf-exposed HCT116 p53(-/-) cells did not, however, show any enhancement of apoptosis induction despite an increase in the DNA damage-sensor accumulation, γH2AX indicating that crocin induced an autophagy-independent classical programmed cell death.

The hazardous effects of three natural food dyes on developmental stages and longevity of Drosophila melanogaster.

Nowadays, food dyes obtained from herbal, animal, microbial and mineral sources are widely used as food additives. In this study, the toxic effects of three different natural food dyes (carmine, turmeric and annatto) on 72 ± 4 h larvae of Oregon-R wild type of Drosophila melanogaster were investigated. For this purpose, four different application doses (50, 75, 100, 125 mg mL(-1)) were chosen by means of preliminary studies. It was determined that larval mortality increased with increasing concentration in the application groups and the toxicity order was carmine > turmeric > annatto. It was observed that the survival rate was highest in the control with 98% and lowest in 125 mg mL(-1) carmine with 16%. In addition, the average lifespan of the adult individuals obtained from third instar larvae was also studied. While the average lifespan was 40.88 ± 1.44 days in the control group, these values were 10.81 ± 0.55-23.90 ± 1.27 days in the carmine group, 15.00 ± 0.80-22.42 ± 1.43 days in the turmeric group and 10.33 ± 1.03-35.68 ± 1.54 days in the annatto group, respectively. According to the obtained results, when both the developmental period from larvae into adults and the lifespan of the developing adults were compared with the control group, the food dyes were found to be toxic and the toxicity order of carmine > turmeric > annatto was identified.

Improved antibacterial behavior of titanium surface with torularhodin-polypyrrole film.

The problem of microorganisms attaching and proliferating on implants and medical devices surfaces is still attracting interest in developing research on different coatings based on antibacterial agents. The aim of this work is centered on modifying titanium (Ti) based implants surfaces through incorporation of a natural compound with antimicrobial effect, torularhodin (T), by means of a polypyrrole (PPy) film. This study tested the potential antimicrobial activity of the new coating against a range of standard bacterial strains: Escherichia coli, Staphylococcus aureus, Enterococcus faecalis, Bacillus subtilis and Pseudomonas aeruginosa. The morphology, physical and electrochemical properties of the synthesized films were assessed by SEM, AFM, UV-Vis, FTIR and cyclic voltammetry. In addition, biocompatibility of this new coating was evaluated using L929 mouse fibroblast cells. The results showed that PPy-torularhodin composite film acts as a corrosion protective coating with antibacterial activity and it has no harmful effect on cell viability.

Bioactivity assessment and toxicity of crocin: a comprehensive review.

Since ancient times, saffron, the dried stigma of the plant Crocus sativus L. has been extensively used as a spice and food colorant; in folk medicine it has been reputed to be efficacious for the alleviation and treatment of ailments. In addition to the three founded major constituents including crocin, picrocrocin and safranal, presence of carotenoids, carbohydrates, proteins, anthocyanins, vitamins and minerals provide valuable insights into the health benefits and nutritional value of saffron. Of the carotenoids present in saffron, highly water-soluble crocin (mono and diglycosyl esters of a polyene dicarboxylic acid, named crocetin) is responsible for the majority of its color, and appears to possess various health-promoting properties, as an antioxidant, antitumor, memory enhancer, antidepressant, anxiolytic and aphrodisiac. It is also worth noting that the crocin principle of saffron exhibited high efficacy along with no major toxicity in experimental models. We would be remiss to not consider the great potential of saffron and crocin, which benefits the cuisine and health of human life throughout the world. The present study provides a comprehensive and updated report of empirical investigations on bioactivities and biological characteristics of crocin.

D-512 and D-440 as novel multifunctional dopamine agonists: characterization of neuroprotection properties and evaluation of in vivo efficacy in a Parkinson's disease animal model.

In this article, we have demonstrated the in vivo efficacy of D-512 and D-440 in a 6-OHDA-induced unilaterally lesioned rat model experiment, a Parkinson's disease animal model. D-512 is a novel highly potent D2/D3 agonist, and D-440 is a novel highly selective D3 agonist. We evaluated the neuroprotective properties of D-512 and D-440 in the dopaminergic MN9D cells. Cotreatment of these two drugs with 6-OHDA and MPP+ significantly attenuated and reversed 6-OHDA- and MPP+-induced toxicity in a dose-dependent manner in the dopaminergic MN9D cells. The inhibition of caspase 3/7 and lipid peroxidation activities along with the restoration of tyrosine hydroxylase levels by D-512 in 6-OHDA-treated cells may partially explain the mechanism of its neuroprotective property. Furthermore, studies were carried out to elucidate the time-dependent changes in the pERK1/2 and pAkt, two kinases implicated in cell survival and apoptosis, levels upon treatment with 6-OHDA in presence of D-512. The neuroprotective property exhibited by these drugs was independent of their dopamine-agonist activity, which is consistent with our multifunctional drug-development approach that is focused on the generation of disease-modifying symptomatic-treatment agents for Parkinson's disease.

Thirteen-week oral toxicity study of carotenoid pigment from Rhodotorula glutinis DFR-PDY in rats.

Carotenoids from some of the coloured yeasts like Rhodotorula, Phaffia rhodozyma have attracted commercial interest as a natural pigment for foods. Red yeast isolated from contaminated Potato dextrose agar plate (PDA), designated as Rhodotorula glutinis DFR-PDY has been found to produce carotenoids. In the present study toxicological evaluation of carotenoid pigment has been reported. Experiment was conducted on 3 groups of albino rats. One group with vehicle control (palm oil) and 2 groups with two different doses of red yeast pigment (lower and higher dose) were fed to rats (both male and female) by gavages for 13 weeks. Gain in body weight of rats and food consumption were monitored at regular intervals. Hematological studies revealed that there is no much difference in erythrocytes, packed cell volume, Mean corpuscular volume (MCV), Mean corpuscular haemoglobin concentration (MCHC), platelets and differential counts. Total leucocyte count (TLC) is less in case of higher dose group than the lower and control groups. Whereas, hemoglobin is more in case of higher dose than the lower dose group and least in control group. Even clinico-chemical parameters and urine analysis of vehicle control group and pigment fed rats revealed that there were no major differences between them as well as between two different genders of rats and also interaction between different doses and the genders. Histopathology of these experimental animals revealed that there are no major histological changes found between the groups. It may be concluded that the whole pigment extract from R. glutinis DFR-PDY may be used safely in food preparations as food colourant with an added benefit of antioxidant activity.

Subacute toxicity assessment of carotenoids extracted from citrus peel (Nanfengmiju, Citrus reticulata Blanco) in rats.

The mixture of carotenoids extracted from citrus peel (Nanfengmiju, Citrus reticulata Blanco) was tested for subacute oral toxicity. In this study, dose levels of 0, 200, 500 and 2000 mg/kg body weight/day were administered by gavage to 10 Wistar rats/sex/group for 28 days. No statistically significant, dose-related effect on food consumption, food efficiency, body weight gain, clinical signs or ophthalmoscopic parameters was observed in any treatment group. Urinalysis, hematological, blood coagulation and serum biochemical examination as well as necropsy or histopathology showed that no observed adverse effect was found. These findings suggested that the No-Observed-Adverse-Effect Level for the mixture of carotenoids extracted from citrus peel was at least 2000 mg/kg body weight/day.