ADME/PK Insights of Crocetin: A Molecule Having an Unusual Chemical Structure with Druglike Features

Crocetin is a promising phyto-based molecule to treat Alzheimer's disease (AD). The chemical structure of crocetin is incongruent with various standard structural features of CNS drugs. As poor pharmacokinetic behavior is the major hurdle for any candidate to become a drug, we elucidated its druggable characteristics by implementing in silico, in vitro, and in vivo approaches, as limited ADME/PK information is available. Results demonstrate several attributes of crocetin based on rules of drug-likeness, lipophilicity, pKa, P-gp inhibitory activity, plasma stability, RBC partitioning, metabolic stability, CYP inhibitory action, blood-brain barrier (BBB) permeability, oral bioavailability, and pharmacokinetic interaction with marketed anti-Alzheimer's drugs (memantine, donepezil, galantamine, and rivastigmine). However, aqueous solubility, chemical stability, plasma protein binding, and P-gp induction are some concerns associated with this molecule that should be taken into consideration during its further development. Overall results indicate favorable ADME/PK behavior and potential druggable candidature of crocetin.

Antidiabetic and antioxidant potential of Crocin in high-fat diet plus streptozotocin-induced type-2 diabetic rats

OBJECTIVES

Crocin, the principal water-soluble active constituent of saffron, possesses numerous pharmacological activities. The present investigation examined the potential antidiabetic and antioxidant characteristics of Crocin in rats with type-2 diabetes by administering it orally and intraperitoneally (i.p.).

METHODS

After 2 weeks of a high-fat diet, streptozotocin (STZ) (i.p., 40 mg/kg) was administered to male adult rats to induce type-2 diabetes mellitus. Body weight and fasting blood glucose (FBG) were measured on days zero, weeks 1, and 2. At the end of 2 weeks of drug administration in their respective groups, fasting insulin and glucose levels were estimated, and insulin resistance (HOMA-IR) was determined. Intraperitoneal glucose (IPGTT) and insulin tolerance tests (ITT) were carried out. Histopathological investigation and biochemical parameters were estimated in pancreatic tissues.

RESULTS

The Crocin (100 mg/kg) treatment has significantly improved body weight, abatement of FBG, fasting insulin, and HOMA-IR. Likewise, Crocin treatment significantly improved the glucose and insulin challenges. We observed a significantly marked elevation in endogenous antioxidant enzymes in Crocin-treated groups. Similarly, Crocin treatment reversed the histopathological changes and restored the normal integrity and function of the pancreas.

CONCLUSION

The overall finding indicates that intraperitoneal administration of Crocin demonstrated better control of glycemic level and body weight. Further, it has improved insulin levels in the serum and potentiated antioxidant properties.

Effect of saffron, black seed, and their main constituents on inflammatory cytokine response (mainly TNF-α) and oxidative stress status: an aspect on pharmacological insights

Tumor necrosis factor-α (TNF-α), an inflammatory cytokine, is produced by monocytes and macrophages. It is known as a 'double-edged sword' because it is responsible for advantageous and disadvantageous events in the body system. The unfavorable incident includes inflammation, which induces some diseases such as rheumatoid arthritis, obesity, cancer, and diabetes. Many medicinal plants have been found to prevent inflammation, such as saffron (Crocus sativus L.) and black seed (Nigella sativa). Therefore, the purpose of this review was to assess the pharmacological effects of saffron and black seed on TNF-α and diseases related to its imbalance. Different databases without time limitations were investigated up to 2022, including PubMed, Scopus, Medline, and Web of Science. All the original articles (in vitro, in vivo, and clinical studies) were collected on the effects of black seed and saffron on TNF-α. Black seed and saffron have therapeutic effects against many disorders, such as hepatotoxicity, cancer, ischemia, and non-alcoholic fatty liver, by decreasing TNF-α levels based on their anti-inflammatory, anticancer, and antioxidant properties. Saffron and black seed can treat a variety of diseases by suppressing TNF-α and exhibiting a variety of activities such as neuroprotective, gastroprotective, immunomodulatory, antimicrobial, analgesic, antitussive, bronchodilator, antidiabetic activity, anticancer, and antioxidant effects. To uncover the beneficial underlying mechanisms of black seed and saffron, more clinical trials and phytochemical research are required. Also, these two plants affect other inflammatory cytokines, hormones, and enzymes, implying that they could be used to treat a variety of diseases.

Bioactive Compounds (BACs): A Novel Approach to Treat and Prevent Cardiovascular Diseases

Cardiovascular diseases (CVDs) are one of the leading disorders of serious death and cause huge economic loss to patients and society. It is estimated that about 18 million people have a high death ratio due to the incidence of CVDs such as (stroke, coronary heart disease, and non-ischemic heart failure). Bioactive compounds (BACs) are healthy nutritional ingredients providing beneficial effects and nutritional value to the human body. Epidemiological studies strongly shed light on several bioactive compounds that are favorable candidates for CVDs treatment. Globally, the high risk of CVDs and related results on human body parts made them a serious scenario in all communities. In this present review, we intend to collect previously published data concerned over the years concerning green-colored foods and their BACs that aim to work in the prevention, diagnosis, and/or systematic treating CVDs. We also comprehensively discussed the oral delivery of several bioactive compounds derived from fruits and vegetables and their bioavailability and physiological effects on human health. Moreover, their important characteristics, such as anti-inflammatory, lowering blood pressure, anti-obesity, antioxidant, anti-diabetics, lipid-lowering responses, improving atherosclerosis, and cardioprotective properties, will be elaborated further. More precisely, medicinal plants' advantages and multifaceted applications have been reported in this literature to treat CVDs. To the best of our knowledge, this is our first attempt that will open a new window in the area of CVDs with the opportunity to achieve a better prognosis and effective treatment for CVDs.

Major Phytochemical Compounds, In Vitro Antioxidant, Antibacterial, and Antifungal Activities of Six Aqueous and Organic Extracts of Crocus sativus L. Flower Waste

PURPOSE

After being considered as a neglected product, agricultural waste is nowadays considered of paramount importance. It has become a source of many chemical compounds with industrial, pharmaceutical, and food applications. This study aims to evaluate the primary phytochemical content, the antioxidant properties, and the antimicrobial activities of different extracts of saffron flower waste (SFE) against bacterial and fungal strains involved in diverse pathologies in southern Morocco.

METHODS

Total phenolic and flavonoid contents were determined. The antioxidant potentials were assessed by DPPH, FRAP, and β-carotene assays. The antimicrobial activity against four bacteria and four fungi was also evaluated. The findings in terms of the relationships between phytochemical content and all activities were depicted by PCA analyses.

RESULTS

SFEs contained large amounts of phenolic and flavonoid compounds that contribute to the significant antioxidant activities. Diethyl ether (DE), n-Butanol (n-B), and Ethyl acetate (EA) fractions respectively exhibited more DPPH scavenging capacity, FRAP reducing power, and β-carotene bleaching inhibition. DE and EA have a remarkable effect mainly against Staphylococcus aureus strain, compared to Listeria monocytogenes, Escherichia coli and Klebsiella pneumoniae. Both SFEs showed antifungal antagonism towards key fungi species involved in post-harvest mold and crop yield losses. Botrytis cinerea was more susceptible than Fusarium solani, Penicillium expansum, and Penicillium digitatum.

CONCLUSION

These results reveal new data about extracts obtained from SFE that could be a potential source of natural antioxidant and antimicrobial agents opening new possibilities for their applications in the food system as a natural preservative and a sustainable alternative to conventional ingredients.

Crocins for Ischemic Stroke: A Review of Current Evidence

Crocins (CRs) and the related active constituents derived from Crocus sativus L. (Saffron) have demonstrated protective effects against cerebral ischemia and ischemic stroke, with various bioactivities including neuroprotection, anti-neuroinflammation, antioxidant, and cardiovascular protection. Among CRs, crocin (CR) has been shown to act on multiple mechanisms and signaling pathways involved in ischemic stroke, including mitochondrial apoptosis, nuclear factor kappa light chain enhancer of B cells pathway, S100 calcium-binding protein B, interleukin-6 and vascular endothelial growth factor-A. CR is generally safe and well-tolerated. Pharmacokinetic studies indicate that CR has poor bioavailability and needs to convert to crocetin (CC) in order to cross the blood-brain barrier. Clinical studies have shown the efficacy of saffron and CR in treating various conditions, including metabolic syndrome, depression, Alzheimer’s disease, and coronary artery disease. There is evidence supporting CR as a treatment for ischemic stroke, although further studies are needed to confirm their efficacy and safety in clinical settings.

An easy way for the hydrolysis, pre-concentration, and chemical stabilization of crocetin from saffron powder

To date there are no methods in the literature leading to crocetin selective concentration from saffron powder aqueous solutions. To this aim, we decided to test the performance of its heterogeneous extraction by means of a panel of 21 synthetic clays, 4 of which demonstrated to selectively retain crocetin in the solid phase after hydrolysis of its digentiobyosil ester (crocin) (and its isomers) and to its chemical stabilization (e.g., oxidation) over time. The best adsorption yield was obtained with zinc hydroxy chloride (66.18 ± 0.06 μg/g dry powder). This phenomenon was assessed by HPLC-DAD analyses after desorption of crocetin from the respective support and assessing its degradation along a period of 30 days. The method we established could represent a good mean to provide pure crocetin from saffron powder, preserving in the meantime its chemical properties for a concrete future exploitation for food pharmaceutical, and cosmetic purposes.

Anti-Depressant Properties of Crocin Molecules in Saffron

Saffron is a valued herb, obtained from the stigmas of the C. sativus Linn (Iridaceae), with therapeutic effects. It has been described in pharmacopoeias to be variously acting, including as an anti-depressant, anti-carcinogen, and stimulant agent. The therapeutic effects of saffron are harbored in its bioactive molecules, notably crocins, the subject of this paper. Crocins have been demonstrated to act as a monoamine oxidase type A and B inhibitor. Furthermore, saffron petal extracts have experimentally been shown to impact contractile response in electrical field stimulation. Other research suggests that saffron also inhibits the reuptake of monoamines, exhibits N-methyl-d-aspartate antagonism, and improves brain-derived neurotrophic factor signaling. A host of experimental studies found saffron/crocin to be similarly effective as fluoxetine and imipramine in the treatment of depression disorders. Saffron and crocins propose a natural solution to combat depressive disorders. However, some hurdles, such as stability and delivery, need to be overcome.

Crocetin: A Systematic Review

Crocetin is an aglycone of crocin naturally occurring in saffron and produced in biological systems by hydrolysis of crocin as a bioactive metabolite. It is known to exist in several medicinal plants, the desiccative ripe fruit of the cape jasmine belonging to the Rubiaceae family, and stigmas of the saffron plant of the Iridaceae family. According to modern pharmacological investigations, crocetin possesses cardioprotective, hepatoprotective, neuroprotective, antidepressant, antiviral, anticancer, atherosclerotic, antidiabetic, and memory-enhancing properties. Although poor bioavailability hinders therapeutic applications, derivatization and formulation preparation technologies have broadened the application prospects for crocetin. To promote the research and development of crocetin, we summarized the distribution, preparation and production, total synthesis and derivatization technology, pharmacological activity, pharmacokinetics, drug safety, drug formulations, and preparation of crocetin.

Crocin Possesses Excellent Hepatoprotective Effects Against Acetaminophen-Induced Hepatotoxicity in Mice

Background: Acetaminophen (APAP) is a common analgesic and antipyretic medicine that can lead to acute liver injury at high doses. Crocin, a Crocus sativus’ ingredient, has potent antioxidant effects. Objectives: This study examined the protective effects of crocin against APAP-induced oxidative stress in mice. Methods: In this study, 56 mice were randomly divided into seven groups (n = 8 per group), including the negative (normal saline, 10 mL/kg) and positive (oral normal saline for five days + a single dose of APAP (300 mg/kg) on day 6th) control groups. The third group (NAC) received normal saline for up to five days, and on the 6th day, immediately after the administration of acetaminophen, received NAC (50 mg/kg). Groups fourth to sixth received respectively 12.5, 25, and 50 mg/kg of crocin (orally for six days), followed by a single dose of APAP (300 mg/kg) on 6th day. The last group received crocin (50 mg/kg) for six days. Then 24 h after the last injection, the animals were sacrificed, and samples were collected for biochemical and histopathological evaluations. Results: The levels of ALT, AST, and MDA increased, and the activity of CAT, GSH, and GPX decreased in the APAP-treated group compared to the control group. In APAP-treated groups, the administration of crocin decreased the serum levels of AST, ALT, and MDA and increased the activity of CAT, GSH, and GPX. Histopathological evaluations confirmed the above findings. Conclusions: According to our results, it seems that crocin has a protective effect against acetaminophen-induced liver toxicity and can be used as a therapeutic agent to treat APAP-induced hepatotoxicity.

Anti-atherosclerotic Effects of Spice-Derived Phytochemicals

Cardiovascular diseases are the leading cause of death in the world. Atherosclerosis is characterized by oxidized lipid deposition and inflammation in the arterial wall and represents a significant problem in public health and medicine. Some dietary spices have been widely used in many countries; however, the mechanism of their action as it relates to the prevention and treatment of atherosclerosis is still poorly understood. In this review, we focus on the properties of various spice-derived active ingredients used in the prevention and treatment of atherosclerosis, as well as associated atherosclerotic risk factors. We provide a summary of the mechanisms of action, epidemiological analyses, and studies of various components of spice used in the clinic, animal models, and cell lines related to atherosclerosis. Most notably, we focused on mechanisms of action by which these spice-derived compounds elicit their lipid-lowering, anti-inflammatory, antioxidant, and immunomodulatory properties, as well as their involvement in selected biochemical and signal transduction pathways. It is suggested that future research should aim to design well-controlled clinical trials and more thoroughly investigate the role of spices and their active components in the prevention/treatment of atherosclerosis. Based on this literature review, it appears that spices and their active components are well tolerated and have few adverse side effects and, therefore, provide a promising adjunctive treatment strategy for patients with atherosclerosis.

Crocetin and related oxygen diffusion-enhancing compounds: Review of chemical synthesis, pharmacology, clinical development, and novel therapeutic applications

The current pandemic forced us to introspect and revisit our armamentarium of medicinal agents which could be life‐saving in emergency situations. Oxygen diffusion‐enhancing compounds represent one such class of potential therapeutic agents, particularly in ischemic conditions. As rewarding as the name suggests, these agents, represented by the most advanced and first‐in‐class molecule, trans‐sodium crocetinate (TSC), are the subject of intense clinical investigation, including Phase 1b/2b clinical trials for COVID‐19. Being a successor of a natural product, crocetin, TSC is being investigated for various cancers as a radiosensitizer owing to its oxygen diffusion enhancement capability. The unique properties of TSC make it a promising therapeutic agent for various ailments such as hemorrhagic shock, stroke, heart attack, among others. The present review outlines various (bio)synthetic strategies, pharmacological aspects, clinical overview and potential therapeutic benefits of crocetin and related compounds including TSC. The recent literature focusing on the delivery aspects of these compounds is covered as well to paint the complete picture to the curious reader. Given the potential TSC holds as a first‐in‐class agent, small‐ and/or macromolecular therapeutics based on the core concept of improved oxygen diffusion from blood to the surrounding tissues where it is needed the most, will be developed in future and satisfy the unmet medical need for many diseases and disorders.

Prospects and progress on crocin biosynthetic pathway and metabolic engineering

Crocins are a group of highly valuable apocarotenoid-derived pigments mainly produced in Crocus sativus stigmas and Gardenia jasminoides fruits, which display great pharmacological activities for human health, such as anticancer, reducing the risk of atherosclerosis, and preventing Alzheimer's disease. However, traditional sources of crocins are no longer sufficient to meet current demands. The recent clarification of the crocin biosynthetic pathway opens up the possibility of large-scale production of crocins by synthetic metabolic engineering methods. In this review, we mainly introduce the crocin biosynthetic pathway, subcellular route, related key enzymes, and its synthetic metabolic engineering, as well as its challenges and prospects, with a view to providing useful references for further studies on the synthetic metabolic engineering of crocins.

Ovarian Cancer HO-8910 Cell Apoptosis Induced by Crocin in vitro

The effect and mechanism of ovarian cancer HO-8910 cell apoptosis induced by crocin. MTT assay was performed to detect the inhibitory action of crocin on the proliferation of HO-8910 cells. Flow cytometry was used to test the cell cycle distribution and apoptosis rate of ovarian cancer HO-8910 cells. Western blot analysis was utilized to measure the levels of apoptotic proteins such as p53, Fas/APO-1, and Caspase-3. MTT analysis revealed that crocin significantly inhibited the growth of HO-8910 cells. Additionally, flow cytometry illustrated that crocin raised the proportion of HO-8910 cells in the G0/G1 phase and increased their apoptosis rate. Furthermore, Western blot analysis revealed that crocin up-regulated the expression of p53, Fas/APO-1, and Caspase-3. The results of this study showed that crocin can significantly inhibit the growth of HO-8910 cells and arrest them in the G0/G1 phase. Crocin can also promote ovarian cancer HO-8910 cell apoptosis, most likely by increasing p53 and Fas/APO-1 expression, and then activating the apoptotic pathway regulated by Caspase-3.

Characterization of By-products of Saffron (Crocus Sativus L.) Production

The stigma, stamens and sepals of Crocus sativus L,. from two different geographical origins, were analyzed for their crocin and flavonol contents. Identification of crocins, safranal, picrocrocin, and flavonols was carried out by HPLC/DAD and HPLC/MS analysis. Both stigma samples, grown under natural conditions, exhibited high crocin contents (between 342 and 231 mg/g), while the stamens and sepals were rich in flavonols (between 6 and 10 mg/g). The stamens contain mainly kaempferol- 3-O-sophoroside, whereas the sepals contain mainly quercetin and methyl-quercetin glycosides. These data may be useful in order to find a possible exploitation of the by-products of saffron production, in which large quantities of C. sativus flowers are available.