Absorption and metabolism of bioactive molecules after oral consumption of cooked edible heads ofCynara scolymusL. (cultivar Violetto di Provenza) in human subjects: a pilot study

The comparative analysis of Lonicerae Japonicae Flos and Lonicerae Flos: A systematical review

ETHNOPHARMACOLOGICAL RELEVANCE

Lonicerae Japonicae Flos (LJF) and Lonicerae Flos (LF) were once used as the same herb in China, but they were distinguished by Chinese Pharmacopoeia in 2005 in terms of their medicinal history, plant morphology, medicinal properties and chemical constituents. However, their functions, flavor, and meridian tropism are the same according to the Chinese pharmacopoeia 2020 edition, making researchers and customers confused.

AIM OF THE REVIEW

This review aimed to provide a comparative analysis of LJF and LF in order to provide a rational application in future research.

MATERIALS AND METHODS

The information was gathered from China National Knowledge Infrastructure (CNKI), SciFinder, Google Scholar, PubMed, Web of Science, and Chinese Masters and Doctoral Dissertations (all chosen articles were reviewed attentively from 1980.1 to 2023.8).

RESULTS

Till now, 507 chemical compounds have been isolated and identified in LJF, while 223 ones (79 overlapped compounds) are found in LF, including organic acids and derivatives, flavonoids, triterpenoids, iridoids, and essential oil components, etc. In addition, the pharmacological activities of LJF and LF, especially for their anti-influenza efficacy and mechanism, and their difference in terms of pharmacokinetic parameters, toxicology, and clinical applications were also summarized.

CONCLUSION

The current work offers comparative information between LJF and LF in terms of botany, traditional uses, phytochemistry, ethnopharmacology, pharmacokinetics, toxicology, and pharmacology, especially their anti-influenza activities. Despite the same clinical applications and similar chemical components in LJF and LF, differentiated components were still existed, resulting in differentiated pharmacological activities and pharmacokinetics parameters. Moreover, the research about anti-influenza mechanism and functional substances of LJF and LF is dramatically limited, restricting their clinical applications. In addition, few studies have investigated the metabolism feature of LF in vivo, which is one of the important bases for revealing the pharmacological mechanism of LF. At the same time, the toxicity of LJF and LF is not fully studied, and the toxic compounds of LJF and LF need to be screened out in order to standardize the drug use and improve their rational applications.

An Overview of the Versatility of the Parts of the Globe Artichoke (Cynara scolymus L.), Its By-Products and Dietary Supplements

Cynara scolymus, also known as the globe artichoke or artichoke, is grown as a food, mainly in the Mediterranean, Canary Islands, and Egypt, as well as in Asia and South America. It has also been associated with various health benefits and is used in plant-based dietary supplements and herbal infusions. Its edible parts, consisting of the head or capitula, flower, and leaves, have shown various biological activities, including anti-cancer, hepatoprotective and antimicrobial potential. The leaves are mainly used in infusions and extracts for their health-promoting properties, although all their edible parts may also be consumed as fresh, frozen, or canned foods. However, its primary health-promoting activity is associated with its antioxidant potential, which has been linked to its chemical composition, particularly its phenolic compounds (representing 96 mg of gallic acid equivalent per 100 g of raw plant material) and dietary fiber. The main phenolic compounds in the heads and leaves are caffeic acid derivatives, while the flavonoids luteolin and apigenin (both present as glucosides and rutinosides) have also been identified. In addition, heat-treated artichokes (i.e., boiled, steamed or fried), their extracts, and waste from artichoke processing also have antioxidant activity. The present paper reviews the current literature concerning the biological properties of different parts of C. scolymus, its by-products and dietary supplements, as well as their chemical content and toxicity. The literature was obtained by a search of PubMed/Medline, Google Scholar, Web of Knowledge, ScienceDirect, and Scopus, with extra papers being identified by manually reviewing the references.

Dihydrocaffeic Acid-Is It the Less Known but Equally Valuable Phenolic Acid?

Dihydrocaffeic acid (DHCA) is a phenolic acid bearing a catechol ring and three-carbon side chain. Despite its being found in minor amounts in numerous plants and fungi of different origins, it has attracted the interest of various research groups in many fields of science, from food to biomedical applications. The review article presented herein aims to show a wider audience the health benefits and therapeutic, industrial, and nutritional potential of dihydrocaffeic acid, by sheddinglight on its occurrence, biosynthesis, bioavailability, and metabolism. The scientific literature describes at least 70 different derivatives of dihydrocaffeic acid, both those occurring naturally and those obtained via chemical and enzymatic methods. Among the most frequently used enzymes that were applied for the modification of the parent DHCA structure, there are lipases that allow for obtaining esters and phenolidips, tyrosinases used for the formation of the catechol ring, and laccases to functionalize this phenolic acid. In many studies, both in vitro and in vivo, the protective effect of DHCA and its derivatives on cells subjected to oxidative stress and inflammation were acknowledged.

Ferulic acid as a therapeutic agent in depression: Evidence from preclinical studies

Depression is a common but severe mood disorder with a very high prevalence across the general population. Depression is of global concern and poses a threat to human physical and mental health. Ferulic acid (FA) is a natural active ingredient that has antioxidative, anti-inflammatory, and free radical scavenging properties. Furthermore, studies have shown that FA can exert antidepressant effects through a variety of mechanisms. The aim of the review was to comprehensively elucidate the mechanisms in FA that alleviate depression using animal models. The in vivo (animal) studies on the mechanism of FA treatment of depression were searched in PubMed, Chinese National Knowledge Infrastructure, Baidu academic, and Wan fang databases. Thereafter, the literature conclusions were summarized accordingly. Ferulic acid was found to significantly improve the depressive-like behaviors of animal models, suggesting that FA is a potential natural product in the treatment of depression. The mechanisms are achieved by enhancing monoamine oxidase A (MOA) activity, inhibiting microglia activation and inflammatory factor release, anti-oxidative stress, promoting hippocampal nerve regeneration, increasing brain-derived neurotrophic factor secretion, regulating gut microbiome, and activating protein kinase B/collapsin response mediator protein 2 (AKT/CRMP2) signaling pathway. Ferulic acid produces significant antidepressant effects in animal depression models through various mechanisms, suggesting its potential value as a treatment of depression. However, clinical research trials involving FA are required further to provide a solid foundation for its clinical application.

Polyphenolic Compound Variation in Globe Artichoke Cultivars as Affected by Fertilization and Biostimulants Application

Globe artichoke is an ancient herbaceous plant native to the Mediterranean Basin. The edible part of the plant is limited to the fleshy leaves (bracts) and receptacle of a large immature inflorescence (head) that has been shown to be a rich source of bioactive compounds. Nutritional and pharmacological properties of artichoke heads and leaves are attributed mainly to polyphenolic compounds and inulin present at high concentration. In this study, polyphenols were investigated in two artichoke cultivars (Opal and Madrigal) in response to four nitrogen rates and foliar applications of biostimulating products under drip irrigation. Field experiments were carried out over two growing seasons (2015–2016, 2016–2017) in Policoro (MT), Southern Italy, on a deep clay soil in sub-humid climate conditions. Phenolic compounds were isolated and characterized by means of high-performance liquid chromatography with photodiode array detection and electrospray ionization/mass spectrometry (HPLC-DAD-MS/MS) analysis. In both cultivars, caffeoylquinic acids were more abundant when a dose of 100 kg ha⁻¹ of ammonium nitrate was provided, whereas apigenins were not affected by nitrogen fertilization. Luteolins increased in cv Opal and decreased in cv Madrigal following N fertilization. The application of biostimulants (3 L ha⁻¹) favored the accumulation of polyphenols, in particular of caffeoylquinic acids and apigenin, in artichoke heads in both cultivars. The results obtained highlight some positive aspects related to the synergistic effect of nitrogen fertilization and biostimulant foliar application.

Effects of Artichoke Supplementation on Liver Enzymes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Studies examining the effect of artichoke on liver enzymes have reported inconsistent results. This systematic review and meta-analysis aimed to assess the effects of artichoke administration on the liver enzymes. PubMed, Embase, the Cochrane Library, and Scopus databases were searched for articles published up to January 2022. Standardized mean difference (Hedges’ g) were analyzed using a random-effects model. Heterogeneity, publication bias, and sensitivity analysis were assessed for the liver enzymes. Pooled analysis of seven randomized controlled trials (RCTs) suggested that the artichoke administration has an effect on both alanine aminotransferase (ALT) (Hedges’ g, −1.08; 95% confidence interval [CI], −1.76 to −0.40; p = 0.002), and aspartate aminotransferase (AST) (Hedges’ g, −1.02; 95% CI, −1.76 to −0.28; p = 0.007). Greater effects on ALT were detected in trials that lasted ≤8 weeks. Also, greater effects on AST were detected in trials using > 500 mg artichoke. Overall, this meta-analysis demonstrated artichoke supplementation decreased ALT and AST.

Phenol Biological Metabolites as Food Intake Biomarkers, a Pending Signature for a Complete Understanding of the Beneficial Effects of the Mediterranean Diet

The Mediterranean diet (MD) has become a dietary pattern of reference due to its preventive effects against chronic diseases, especially relevant in cardiovascular diseases (CVD). Establishing an objective tool to determine the degree of adherence to the MD is a pending task and deserves consideration. The central axis that distinguishes the MD from other dietary patterns is the choice and modality of food consumption. Identification of intake biomarkers of commonly consumed foods is a key strategy for estimating the degree of adherence to the MD and understanding the protective mechanisms that lead to a positive impact on health. Throughout this review we propose potential candidates to be validated as MD adherence biomarkers, with particular focus on the metabolites derived from the phenolic compounds that are associated with the consumption of typical Mediterranean plant foods. Certain phenolic metabolites are good indicators of the intake of specific foods, but others denote the intake of a wide-range of foods. For this, it is important to emphasise the need to increase the number of dietary interventions with specific foods in order to validate the biomarkers of MD adherence. Moreover, the identification and quantification of food phenolic intake biomarkers encouraging scientific research focuses on the study of the biological mechanisms in which polyphenols are involved.

In vivo study of the bioavailability and metabolic profile of (poly)phenols after sous-vide artichoke consumption

Artichokes are a rich source of (poly)phenols, mainly caffeoylquinic acids, but little is known about their bioavailability from this source. This study investigated the absorption, metabolism and excretion of (poly)phenols after sous-vide artichoke consumption (5776 µmol of (poly)phenols) by healthy volunteers. Seventy-six (poly)phenol metabolites were identified by UHPLC-MS/MS using authentic standards, including acyl-quinic acids plus C₆-C₃, C₆-C₁, C₆-C₂, C₆-C₁-N, C₆-C₀ metabolites, and their phase-II conjugates. The major metabolites were 3'-methoxy-4'-hydroxycinnamic acid, 3'-methoxycinnamic acid-4'-sulfate, and 4'-hydroxycinnamic acid-3'-sulfate, which appeared early in plasma (T_max < 4 h); plus 3-(3'-methoxy-4'-hydroxyphenyl)propanoic acid, 3-(4'-methoxyphenyl)propanoic acid-3'-glucuronide, 3-(3'-hydroxyphenyl) propanoic acid and hippuric acids, which appeared later (T_max > 6 h). The 24 h urinary recovery averaged 8.9% (molar basis) of the (poly)phenols consumed. Hepatic beta-oxidation of 3',4'-dihydroxycinnamic acid and methylated conjugates occurred, but was limited (<0.04%). 3'-Methylation exceeded 4'-methylation and interindividual variability was high, especially for gut microbial metabolites (up to 168-fold).

Dietary Effects of Anthocyanins in Human Health: A Comprehensive Review

In recent years, the consumption of natural-based foods, including beans, fruits, legumes, nuts, oils, vegetables, spices, and whole grains, has been encouraged. This fact is essentially due to their content in bioactive phytochemicals, with the phenolic compounds standing out. Among them, anthocyanins have been a target of many studies due to the presence of catechol, pyrogallol, and methoxy groups in their chemical structure, which confer notable scavenging, anti-apoptotic, and anti-inflammatory activities, being already recommended as supplementation to mitigate or even attenuate certain disorders, such as diabetes, cancer, and cardiovascular and neurological pathologies. The most well-known anthocyanins are cyanidin 3-O-glucoside and cyanidin 3-O-rutinoside. They are widespread in nature, being present in considerable amounts in red fruits and red vegetables. Overall, the present review intends to discuss the most recent findings on the potential health benefits from the daily intake of anthocyanin-rich foods, as well as their possible pharmacological mechanisms of action. However, before that, some emphasis regarding their chemical structure, dietary sources, and bioavailability was done.

Callus culture as a new approach for the production of high added value compounds in Ilex paraguariensis: genotype influence, medium optimization and compounds identification

Ilex paraguariensis (yerba mate) is a native species from South America and is a rich source of bioactive compounds. There is a lack of research efforts on the phytochemical investigation of callus culture from this species. In the present study, an effort was made to optimize callus culture conditions and to identify secondary compounds. Calli were induced from 10 genotypes using leaf explants and the best genotype was selected to evaluate the effects of cytokinin types and concentrations on callus induction and biomass accumulation. The best genotype and cytokinin treatment were used to conduct one last experiment with sucrose concentrations in culture media and its effects on calli biomass, antioxidant activity and secondary compounds accumulation. Callus initiation was genotype dependent, and the 6-156-6 line had the best response. Zeatin supplemented medium showed higher callus induction rate (82%) and higher biomass accumulation after 120 days (328.2 mg). Higher biomass and secondary compounds accumulation were observed for calli on 3% sucrose medium. Antioxidant activity was not affected by sucrose concentrations. Yerba mate callus culture allowed the accumulation of chlorogenic acid, cryptochlorogenic acid, neochlorogenic acid, 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid, theobromine and caffeine.

Natural Sources, Pharmacokinetics, Biological Activities and Health Benefits of Hydroxycinnamic Acids and Their Metabolites

Hydroxycinnamic acids (HCAs) are important natural phenolic compounds present in high concentrations in fruits, vegetables, cereals, coffee, tea and wine. Many health beneficial effects have been acknowledged in food products rich in HCAs; however, food processing, dietary intake, bioaccessibility and pharmacokinetics have a high impact on HCAs to reach the target tissue in order to exert their biological activities. In particular, metabolism is of high importance since HCAs' metabolites could either lose the activity or be even more potent compared to the parent compounds. In this review, natural sources and pharmacokinetic properties of HCAs and their esters are presented and discussed. The main focus is on their metabolism along with biological activities and health benefits. Special emphasis is given on specific effects of HCAs' metabolites in comparison with their parent compounds.

A descriptive bibliometric study on bioavailability of pesticides in vegetables, food or wine research (1976-2018)

A bibliometric analysis based on the Web of Science© (WOS) database was performed on bioavailability of pesticides in vegetables, food or wine related studies published from inception to 2018. A total of 1202 articles were subjected to examination. The results reveal that yearly production of scientific articles increased steadily. Journal and institution production, and author's keywords frequencies followed the Lotka's Law. Khan SU and White JC were the most productive authors. The most productive journals were Journal of Agricultural and Food Chemistry (55), and Journal of Ethnopharmacology (48), and the most common WOS subject category was Pharmacology & Pharmacy (419). USA (h-index of 40) produced 21.7 % of all articles, closely followed by China (20.6 %). Chinese Academy of Sciences (34) was the most productive research institutions. Finally, current and future trends in this area should focus on keywords such as pharmacokinetics, curcumin, in-vitro, nanoparticles, oral (bioavailability) and cell.

Degradation and regulation of edible flower pigments under thermal processing: a review

More and more consumers are aware of the potential health benefits of edible flower pigments. With the increased popularity and broader application of edible flower pigments, their degradation under thermal processing has attracted researchers' attention, because this may affect the pigment functionalities. At high temperature of thermal processing, polyene pigments are easy to oxidize, degrade and isomerize due to high unsaturation, and phenolic pigments may hydrolyze and isomerize of glycosides, which will result in the decreased antioxidant activity and eating quality, and discounted potential health benefits. Therefore, it is very important to understand the degradation mechanisms of edible flower pigments under thermal processing, which is important to develop corresponding control methods to minimize such negative impacts. This review paper discussed the recent development in the degradation mechanisms and regulation methods of edible flower pigments under thermal processing.

Polyphenols and Sesquiterpene Lactones from Artichoke Heads: Modulation of Starch Digestion, Gut Bioaccessibility, and Bioavailability following In Vitro Digestion and Large Intestine Fermentation

Artichoke is a relevant source of health-promoting compounds such as polyphenols and sesquiterpene lactones. In this study, the bioaccessibility and gut bioavailability of artichoke constituents were evaluated by combining in vitro digestion and large intestine fermentation, metabolomics, and Caco-2 human intestinal cells model. Moreover, the ability of artichoke polyphenols to modulate the in vitro starch digestibility was also explored. An untargeted metabolomic approach based on liquid chromatography quadrupole-time-of-flight (UHPLC/QTOF) mass spectrometry coupled with multivariate statistics was used to comprehensively screen the phytochemical composition of raw, digested, and fermented artichoke. Overall, a large abundance of phenolic acids and sesquiterpene lactones was detected, being 13.77 and 11.99 mg·g-1, respectively. After 20 h of in vitro large intestine fermentation, a decrease in polyphenols and sesquiterpene lactones content was observed. The most abundant compounds characterizing the raw material (i.e., chlorogenic acid and cynaropicrin equivalents) showed an average % bioaccessibility of 1.6%. The highest % bioaccessibility values were recorded for flavonoids such as anthocyanin and flavone equivalents (on average, 13.6%). However, the relatively high bioavailability values recorded for flavonols, phenolic acids, and sesquiterpene lactones (from 71.6% up to 82.4%) demonstrated that these compounds are able to be transported through the Caco-2 monolayer. The phenolic compounds having the highest permeation rates through the Caco-2 model included low molecular weight phenolics such as tyrosol and 4-ethylcatechol; the isoflavonoids 3'-O-methylviolanone, equol 4'-O-glucuronide, and hydroxyisoflavone; together with the methyl and acetyl derivatives of glycosylated anthocyanins. Therefore, although human in vivo confirmatory trials are deemed possible, current findings provide insights into the mechanistic effects underlying artichoke polyphenols and sesquiterpenoids bioavailability following gastrointestinal and large intestine processes.

Food intake biomarkers for green leafy vegetables, bulb vegetables, and stem vegetables: a review

BACKGROUND

Numerous studies acknowledged the importance of an adequate vegetable consumption for human health. However, current methods to estimate vegetable intake are often prone to measurement errors due to self-reporting and/or insufficient detail. More objective intake biomarkers for vegetables, using biological specimens, are preferred. The only concentration biomarkers currently available are blood carotenoids and vitamin C, covering total fruit and vegetable intake. Identification of biomarkers for specific vegetables is needed for a better understanding of their relative importance for human health. Within the FoodBAll Project under the Joint Programming Initiative "A Healthy Diet for a Healthy Life", an ambitious action was undertaken to identify candidate intake biomarkers for all major food groups consumed in Europe by systematically reviewing the existent literature. This study describes the review on candidate biomarkers of food intake (BFIs) for leafy, bulb, and stem vegetables, which was conducted within PubMed, Scopus and Web of Science for studies published through March 2019.

RESULTS

In total, 65 full-text articles were assessed for eligibility for leafy vegetables, and 6 full-text articles were screened for bulb and stem vegetables. Putative BFIs were identified for spinach, lettuce, endive, asparagus, artichoke, and celery, but not for rocket salad. However, after critical evaluation through a validation scheme developed by the FoodBAll consortium, none of the putative biomarkers appeared to be a promising BFI. The food chemistry data indicate that some candidate BFIs may be revealed by further studies.

CONCLUSION

Future randomized controlled feeding studies combined with observational studies, applying a non-targeted metabolomics approach, are needed in order to identify valuable BFIs for the intake of leafy, bulb, and stem vegetables.

Anticancer effects induced by artichoke extract in oral squamous carcinoma cell lines

BACKGROUND

Oral squamous cell carcinoma is occupying the eighth position of all malignant neoplasia worldwide. Nowadays, natural compounds found in vegetables and fruits are important resources of many anticancer drugs especially those with high levels of phytochemicals representing an efficient strategy for cancer prevention and treatment. Artichoke (Cynara cardunculus L.) is a kind of antioxidant-rich vegetables demonstrated a potential anticancer activity on various types of cancer cells related to its content of phenolic compounds. Anticarcinogenic effects of polyphenolic extracts were reported to cause a reduction in cell viability, inhibition of cell growth, and initiation of apoptotic mechanisms. The present study aimed to investigate the cell cycle arrest, cytotoxic, and apoptotic effects of artichoke extract against the invasive oral squamous cell carcinoma.

RESULTS

A pure extract from the edible part and leaves of fresh artichoke was added to oral squamous carcinoma cell lines and to control group to evaluate the expression of caspase-9, Bcl-2, and Bax genes. Artichoke extract demonstrated the highest cytotoxic effect against cancer cell lines which increased in a time-dependent manner. No apparent effects were observed in the normal control group. Expression of Bax and caspase-9 genes revealed a highly significant increase in cancer cell lines (p = 0.0001) when compared to the control group. In addition to a highly significant decrease (p = 0.005) in Bcl-2 of cancer cells. It was demonstrated that artichoke extract induced cell growth arrest at G2/M phase which revealed a significant increase (p < 0.05) in comparison to the untreated control group.

CONCLUSION

Artichoke exerts potent cell cycle arrest, cytotoxic, and apoptotic effects on oral squamous carcinoma cell lines.

Artichoke Polyphenols Sensitize Human Breast Cancer Cells to Chemotherapeutic Drugs via a ROS-Mediated Downregulation of Flap Endonuclease 1

Combined treatment of several natural polyphenols and chemotherapeutic agents is more effective comparing to the drug alone in inhibiting cancer cell growth. Polyphenolic artichoke extracts (AEs) have been shown to have anticancer properties by triggering apoptosis or reactive oxygen species- (ROS-) mediated senescence when used at high or low doses, respectively. Our aim was to explore the chemosensitizing potential of AEs in order to enhance the efficacy of conventional chemotherapy in breast cancer cells. We employed breast cancer cell lines to assess the potential synergistic effect of a combined treatment of AEs/paclitaxel (PTX) or AEs/adriamycin (ADR) and to determine the underlying mechanisms correlated to this potential therapeutic approach. Our data shows that AEs/PTX reduced cell proliferation by increasing DNA damage response (DDR) mediated by Flap endonuclease 1 (FEN1) downregulation that results into enhanced breast cancer cell sensitivity to chemotherapeutic drugs. We demonstrated that ROS/Nrf2 and p-ERK pathways are two molecular mechanisms involved in the synergistic effect of AEs plus PTX treatment. To highlight the role of ROS herein, we report that the addition of antioxidant N-acetylcysteine (NAC) significantly decreased the antiproliferative effect of the combined treatment. A combined therapy could be able to reduce the dose of chemotherapeutic drugs, minimizing toxicity and side effects. Our results suggest the use of artichoke polyphenols as ROS-mediated sensitizers of chemotherapy paving the way for innovative and promising natural compound-based therapeutic strategies in oncology.

Effects of phenolic compounds from aqueous extract of Trifolium repens against acetaminophen-induced hepatotoxicity in mice

The aqueous extract of Trifolium repens (TR) leaves was analyzed for the phenolic profile using reversed phase HPLC-DAD and administered to mice against acetaminophen-induced hepatoxicity. Twenty-four phenolic compounds were identified and quantified. The highest amounts present were of kaempferol-3-(caffeoyldiglucoside)-7-glucoside (983.7 µg/ml), followed by p-coumaroyl-4-glucoside (905.6 µg/ml) and daidzein-O-sulfate (808.3 µg/ml). The aqueous extract was administered to mice along with acetaminophen at different doses. Acetaminophen was found to significantly alter body weight, serum biochemistry, and hematological indices of mice, which were ameliorated by the co-administration of aqueous extract. Liver histopathological studies revealed that acetaminophen significantly induced toxicity, while TR aqueous extract provides curative functions. Lipid peroxidation and total reduced glutathione in the liver were also normalized by the aqueous extract of TR. The aqueous extract of TR was rich in important phenolic compounds, which can be used as a source of beneficial bioactive compounds with hepato-protective function. PRACTICAL APPLICATIONS: Acetaminophen has been widely used as antipyretic and analgesic. However, the major complication reported is hepatotoxicity. Synthetic or conventional drugs used for hepatic diseases or against hepatotoxicity are insufficient and causes severe side effects. For this purpose, traditional medicinal plants or nutraceuticals are used to decrease in the side effects of different hepatotoxic medicine are demanding. Food and neutraceuticals are rich in important polyphenolic compounds which are the best antioxidants. This study was aimed to evaluate the phenolic composition of aqueous extract of Trifolium repens and its potential protective action against the acetaminophen-induced toxicity in mice. This study showed for the first time that the aqueous extract of TR was protective against the hepatotoxicity induced by acetaminophen.

The antioxidant activity of artichoke (Cynara scolymus): A systematic review and meta-analysis of animal studies

Current evidence has shown antioxidant activity of artichoke as a potent source of antioxidant compounds. However, it seems that the antioxidant activity of artichoke has not yet been reviewed. Therefore, the present study was designed to perform a systematic review of human studies, animal models, and in vitro systems and to conduct a meta-analysis of animal studies on the antioxidant effects of artichoke. We searched four electronic databases till April 2018 using relevant keywords. All English language articles were assessed. For animal studies, standardized mean difference was pooled using a random effects model. The included studies were evaluated for eligibility and risk of bias. Thirty-nine articles (two human, 23 animal, and 14 in vitro studies) were reviewed. The results of in vitro systems supported the antioxidant effect of artichoke, whereas limited clinical trials indicated no change or a slight improvement of antioxidant status. Finding of animal studies indicated that artichoke extract supplementation increased superoxide dismutase, catalase, glutathione, and glutathione peroxidase level in liver, as well as, decreased malondialdehyde level in liver and plasma of animals with induced disease significantly compared with comparison group. This meta-analysis provided convincing evidence for antioxidant activity of artichoke in animals.

Isolation and Characterization of the Flavonol Regulator CcMYB12 From the Globe Artichoke [Cynara cardunculus var. scolymus (L.) Fiori]

Flavonoids are a well-studied group of secondary metabolites, belonging to the phenylpropanoid pathway. Flavonoids are known to exhibit health promoting effects such as antioxidant capacities, anti-cancer and anti-inflammatory activity. Globe artichoke is an important source of bioactive phenolic compounds, including flavonoids. To study the regulation of their biosynthesis, a R2R3-MYB transcription factor, CcMYB12, was isolated from artichoke leaves. Phylogenetic analysis showed that this protein belongs to the MYB subgroup 7 (flavonol-specific MYB), which includes Arabidopsis AtMYB12, grapevine VvMYBF1, and tomato SlMYB12. CcMYB12 transcripts were detected specifically in artichoke immature inflorescence and young leaves and overlapped with the profiles of flavonol biosynthetic genes. Electrophoretic mobility shift assays (EMSAs) revealed that recombinant CcMYB12 protein is able to bind to ACII element, a DNA binding site ubiquitously present in the promoters of genes encoding flavonol biosynthetic enzymes. In transgenic Arabidopsis plants, the overexpression of CcMYB12 activated the expression of endogenous flavonol biosynthesis genes, leading to an increase of flavonol accumulation and a decrease of anthocyanins in leaves. Likewise, in transgenic tobacco petals and leaves, the overexpression of CcMYB12 decreased anthocyanin levels and increased flavonols.

Potential bioaccessibility and functionality of polyphenols and cynaropicrin from breads enriched with artichoke stem

In this study, an artichoke stem powder (ASP) was used at three concentrations (3%, 6% and 9%) in the formulation of new breads. The bioaccessibility of polyphenols and cynaropicrin from the ASP-enriched breads was evaluated in vitro by using a digestion model combined to high resolution mass spectrometry analysis. The overall total antioxidant capacity of the bioaccessible and unsolubilized fractions obtained during the intestinal steps and the potential ability to modulate α-glucosidase activity were tested. Data showed that 82% of totally bioaccessible polyphenols and 74% of cynaropicrin were released during the duodenal digestion whereas 88% of caffeic acid was released in the colon step. The antioxidant capacity and the α-glucosidase inhibitory activity of the duodenal extract correlated with the amount of ASP in the bread. Data demonstrated that ASP might be a valuable functional ingredient to create a reducing environment in the intestine and to partially modulate glucose metabolism.

Structural constraints and importance of caffeic acid moiety for anti-hyperglycemic effects of caffeoylquinic acids from chicory

SCOPE

Chicory (Cichorium intybus L.) is a perennial herb often consumed as a vegetable, whereas the ground and roasted roots are blended as a coffee substitute. Caffeoylquinic or chlorogenic acids (CQA), the abundant intermediates of lignin biosynthesis in chicory, have been reported to improve glucose metabolism in humans, but the functional group in their structure responsible for this effect has not been yet characterized.

METHODS AND RESULTS

Here, we showed that three di-O-caffeoylquinic acids suppressed hepatic glucose production in H4IIE rat hepatoma cells by reducing expression of glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK), two key enzymes that regulate hepatic gluconeogenesis. Direct comparisons between CQAs and their metabolites (3-caffeoylquinic, caffeic, and quinic acids) revealed the caffeic acid moiety alone was responsible for the observed effects. Further analysis suggested the activation of PI3K and MAPK pathways as a method of controlling gene expression was shared between caffeoylquinic and caffeic acids. These compounds promoted increased mitochondrial respiration and cellular metabolism, in part by inducing oxidative phosphorylation and proton leak.

CONCLUSION

We concluded that the caffeic acid moiety was important for suppression of hepatic gluconeogenesis and hyperglycemia, ultimately strengthening the link between dietary interventions based on caffeic acid-containing plant foods and healthy glucose metabolism.

Histochemistry and immunolocalisation of glucokinin in antidiabetic plants used in traditional Mexican medicine

Mexico is a megadiverse country that has 3,600 to 4,000 species of medicinal plants, of which approximately 800 are used to treat conditions related to diabetes mellitus (DM). DM is a chronic degenerative disease of energy metabolism that exists as two types: type 1 (DM1) and type 2 (DM2). DM is considered a public health problem that affects 7% of the Mexican population older than 20 years. DM is clinically controlled with hypoglycaemic drugs, alpha-glucosidase inhibitors, insulin secretion stimulants or the direct application of insulin. The hypoglycaemic effectiveness of specific molecules has been determined only for some medicinal plants in Mexico used to treat DM2. The presence of molecules called glucokinins, wich are similar to animal insulin molecules, has been reported in some plant species; glucokinins act as both growth factors and regulators of glucose metabolism in plants. Therefore, we hypothesized that the hypoglycaemic effectiveness of some of the popularly used species for the control of DM could be due to the presence of glucokinin, as reported for Bauhinia variegata. The goal of this work was to use histochemistry to detect, the accumulation of protein that is immunocytochemically compatible with glucokinin in slide sections of hypoglycaemic species used as remedies for DM2. The top fourteen most used medicinal plants in Mexico were selected for study via microscopic sections. Proteins were histochemically detected using naphthol blue black and Johansen's quadruple stain, and the immunocytochemical correspondence of the proteins with glucokinin was investigated using an insulin antibody. All species studied reacted positively to proteins and glucokinin in the same structures. The presence of glucokinin in these structures and the corresponding hypoglycaemic effects are discussed in the contex of the actions of other compounds.

Flavones: Food Sources, Bioavailability, Metabolism, and Bioactivity

Flavones are a class of flavonoids that are a subject of increasing interest because of their biological activities in vitro and in vivo. This article reviews the major sources of flavones and their concentrations in food and beverages, which vary widely between studies. It also covers the roles of flavones in plants, the influence of growing conditions on their concentrations, and their stability during food processing. The absorption and metabolism of flavones are also reviewed, in particular the intestinal absorption of both O- and C-glycosides. Pharmacokinetic studies in both animals and humans are described, comparing differences between species and the effects of glycosylation on bioavailability. Biological activity in animal models and human dietary intervention studies is also reviewed. A better understanding of flavone sources and bioavailability is needed to understand mechanisms of action and nutritional intervention.

Role of the small intestine, colon and microbiota in determining the metabolic fate of polyphenols

(Poly)phenols are a large group of compounds, found in food, beverages, dietary supplements and herbal medicines. Owing to interest in their biological activities, absorption and metabolism of the most abundant compounds in humans are well understood. Both the chemical structure of the phenolic moiety and any attached chemical groups define whether the polyphenol is absorbed in the small intestine, or reaches the colon and is subject to extensive catabolism by colonic microbiota. Untransformed substrates may be absorbed, appearing in plasma primarily as methylated, sulfated and glucuronidated derivatives, with in some cases the unchanged substrate. Many of the catabolites are well absorbed from the colon and appear in the plasma either similarly conjugated, or as glycine conjugates, or in some cases unchanged. Although many (poly)phenol catabolites have been identified in human plasma and/or urine, the exact pathways from substrate to final microbial catabolite, and the species of bacteria and enzymes involved, are still scarcely reported. While it is clear that the composition of the human gut microbiota can be modulated in vivo by supplementation with some (poly)phenol-rich commodities, such modulation is definitely not an inevitable consequence of supplementation; it depends on the treatment, length of time and on the individual metabotype, and it is not clear whether the modulation is sustained when supplementation ceases. Some catabolites have been recorded in plasma of volunteers at concentrations similar to those shown to be effective in in vitro studies suggesting that some benefit may be achieved in vivo by diets yielding such catabolites.

Impact of novel SNPs identified in Cynara cardunculus genes on functionality of proteins regulating phenylpropanoid pathway and their association with biological activities

BACKGROUND

Cynara cardunculus L. offers a natural source of phenolic compounds with the predominant molecule being chlorogenic acid. Chlorogenic acid is gaining interest due to its involvement in various biological properties such as, antibacterial, antifungal, antioxidant, hepatoprotective, and anticarcinogenic activities.

RESULTS

In this work we screened a Cynara cardunculus collection for new allelic variants in key genes involved in the chlorogenic acid biosynthesis pathway. The target genes encode p-coumaroyl ester 3'-hydroxylase (C3'H) and hydroxycinnamoyl-CoA: quinate hydroxycinnamoyl transferase (HQT), both participating in the synthesis of chlorogenic acid. Using high-resolution melting, the C3'H gene proved to be highly conserved with only 4 haplotypes while, for HQT, 17 haplotypes were identified de novo. The putative influence of the identified polymorphisms in C3'H and HQT proteins was further evaluated using bioinformatics tools. We could identify some polymorphisms that may lead to protein conformational changes. Chlorogenic acid content, antioxidant and antithrombin activities were also evaluated in Cc leaf extracts and an association analysis was performed to assess a putative correlation between these traits and the identified polymorphisms.

CONCLUSION

In this work we identified allelic variants with putative impact on C3'H and HQT proteins which are significantly associated with chlorogenic acid content and antioxidant activity. Further study of these alleles should be explored to assess putative relevance as genetic markers correlating with Cynara cardunculus biological properties with further confirmation by functional analysis.

Ferulic Acid Improves Cognitive Skills Through the Activation of the Heme Oxygenase System in the Rat

Over the last years, many studies reported on the antioxidant effects of ferulic acid (FA) in preclinical models of dementia through the activation of the heme oxygenase/biliverdin reductase (HO/BVR) system. However, only a few studies evaluated whether FA could improve neurological function under milder conditions, such as psychological stress. The aim of this study was to investigate the effects of FA (150 mg/kg intraperitoneal route) on cognitive function in male Wistar rats exposed to emotional arousal. Animals were randomly assigned to two experimental groups, namely not habituated or habituated to the experimental context, and the novel object recognition test was used to evaluate their cognitive performance. The administration of FA significantly increased long-term retention memory in not habituated rats. Ferulic acid increased the expression of HO-1 in the hippocampus and frontal cortex of not habituated rats only, whereas HO-2 resulted differently modulated in these cognitive brain areas. No significant effects on either HO-1 or HO-2 or BVR were observed in the cerebellum of both habituated and not habituated rats. Ferulic acid activated the stress axis in not habituated rats, as shown by the increase in hypothalamic corticotrophin-releasing hormone levels. Pre-treatment with Sn-protoporphyrin-IX [0.25 μmol/kg, intracerebroventricular route (i.c.v.)], a well-known inhibitor of HO activity through which carbon monoxide (CO) and biliverdin (BV) are generated, abolished the FA-induced improvement of cognitive performance only in not habituated rats, suggesting a role for HO-derived by-products. The CO-donor tricarbonyldichlororuthenium (II) (30 nmol/kg i.c.v.) mimicked the FA-related improvement of cognitive skills only in not habituated rats, whereas BV did not have any effect in any group. In conclusion, these results set the stage for subsequent studies on the neuropharmacological action of FA under conditions of psychological stress.

Chlorogenic acids and the acyl-quinic acids: discovery, biosynthesis, bioavailability and bioactivity

This review is focussed upon the acyl-quinic acids, the most studied group within theca.400 chlorogenic acids so far reported.

The Effect of Artichoke Leaf Extract on Alanine Aminotransferase and Aspartate Aminotransferase in the Patients with Nonalcoholic Steatohepatitis

Background. Based on recent basic and clinical investigations, the extract of artichoke (Cynara scolymus) leaf has been revealed to be used for hepatoprotective and cholesterol reducing purposes. We aimed to assess the therapeutic effects of artichoke on biochemical and liver biomarkers in patients with nonalcoholic steatohepatitis (NASH). Methods. In a randomized double blind clinical trial, 60 consecutive patients suffering NASH were randomly assigned to receive Cynara scolymus extract (as 6 tablets per day consisting of 2700 mg extract of the herb) as the intervention group or placebo as the control group for two months. Results. Comparing changes in study markers following interventions showed improvement in liver enzymes. The levels of triglycerides and cholesterol were significantly reduced in the group treated with Cynara scolymus when compared to placebo group. To compare the role of Cynara scolymus use with placebo in changes in study parameters, multivariate linear regression models were employed indicating higher improvement in liver enzymes and also lipid profile particularly triglycerides and total cholesterol following administration of Cynara scolymus in comparison with placebo use. Conclusion. This study sheds light on the potential hepatoprotective activity and hypolipidemic effect of Cynara scolymus in management of NASH. This clinical trial is registered in the IRCT, Iranian Registry of Clinical Trials, by number IRCT2014070218321N1.

Polyphenols from artichoke heads (Cynara cardunculus (L.) subsp. scolymus Hayek): in vitro bio-accessibility, intestinal uptake and bioavailability

Artichoke is a rich source of health promoting compounds such as polyphenols, important for their pharmaceutical and nutritional properties. In this study, the potential for bioavailability of the artichoke polyphenols was estimated by using both in vitro digestion and Caco-2 human intestinal cell models. In vitro digestive recoveries (bio-accessibility) were found to be 55.8% for total artichoke phenolics and in particular, 70.0% for chlorogenic acid, 41.3% for 3,5-O-dicaffeoylquinic acid, and 50.3% for 1,5-O-dicaffeoylquinic acid, highlighting potential sensitivity of these compounds to gastric and small intestinal digestive conditions. Uptake of artichoke polyphenols was rapid with peak accumulation occurring after 30 min with an efficiency of 0.16%, according to the poor uptake of dietary polyphenols. Some compounds, such as coumaric acid, caffeic acid and caffeic acid derivatives, were also detected in the basolateral side assuming extra and intracellular esterase activities on chlorogenic acid. Only apigenin-7-O-glucoside was transported through the Caco-2 monolayer demonstrating its bioavailability to the extent of 1.15% at 60 min. In addition, permeability coefficient (Papp = 2.29 × 10(-5) cm s(-1)), involving apical to basolateral transport of apigenin 7-O-glucoside, was calculated to facilitate estimation of transport through the Caco-2 monolayer. Finally, the mono and dicaffeoylquinic acids present in artichoke heads exert an antioxidant activity on the human low density lipoprotein system correlated to their chemical structure. In conclusion, the utilized in vitro models, although not fully responding to the morphological and physiological features of human in vivo conditions, could be a useful tool for investigating mechanistic effects of polyphenols released from the food matrix.

Long Term Exposure to Polyphenols of Artichoke (Cynara scolymus L.) Exerts Induction of Senescence Driven Growth Arrest in the MDA-MB231 Human Breast Cancer Cell Line

Polyphenolic extracts from the edible part of artichoke (Cynara scolymus L.) have been shown to be potential chemopreventive and anticancer dietary compounds. High doses of polyphenolic extracts (AEs) induce apoptosis and decrease the invasive potential of the human breast cancer cell line, MDA-MB231. However, the molecular mechanism underlying AEs antiproliferative effects is not completely understood. We demonstrate that chronic and low doses of AEs treatment at sublethal concentrations suppress human breast cancer cell growth via a caspases-independent mechanism. Furthermore, AEs exposure induces a significant increase of senescence-associated β-galactosidase (SA-β-gal) staining and upregulation of tumour suppressor genes, p16^INK4a and p21^Cip1/Waf1 in MDA-MB231 cells. AEs treatment leads to epigenetic alterations in cancer cells, modulating DNA hypomethylation and lysine acetylation levels in total proteins. Cell growth arrest correlates with increased reactive oxygen species (ROS) production in AEs treated breast cancer cells. Inhibition of ROS generation by N-acetylcysteine (NAC) attenuates the antiproliferative effect. These findings demonstrate that chronic AEs treatment inhibits breast cancer cell growth via the induction of premature senescence through epigenetic and ROS-mediated mechanisms. Our results suggest that artichoke polyphenols could be a promising dietary tool either in cancer chemoprevention or/and in cancer treatment as a nonconventional, adjuvant therapy.

The pharmacokinetics of anthocyanins and their metabolites in humans

BACKGROUND AND PURPOSE

Anthocyanins are phytochemicals with reported vasoactive bioactivity. However, given their instability at neutral pH, they are presumed to undergo significant degradation and subsequent biotransformation. The aim of the present study was to establish the pharmacokinetics of the metabolites of cyanidin-3-glucoside (C3G), a widely consumed dietary phytochemical with potential cardioprotective properties.

EXPERIMENTAL APPROACH

A 500 mg oral bolus dose of 6,8,10,3′,5′-¹³C₅-C3G was fed to eight healthy male participants, followed by a 48 h collection (0, 0.5, 1, 2, 4, 6, 24, 48 h) of blood, urine and faecal samples. Samples were analysed by HPLC-ESI-MS/MS with elimination kinetics established using non-compartmental pharmacokinetic modelling.

KEY RESULTS

Seventeen ¹³C-labelled compounds were identified in the serum, including ¹³C₅-C3G, its degradation products, protocatechuic acid (PCA) and phloroglucinaldehyde (PGA), 13 metabolites of PCA and 1 metabolite derived from PGA. The maximal concentrations of the phenolic metabolites (C_max) ranged from 10 to 2000 nM, between 2 and 30 h (t_max) post-consumption, with half-lives of elimination observed between 0.5 and 96 h. The major phenolic metabolites identified were hippuric acid and ferulic acid, which peaked in the serum at approximately 16 and 8 h respectively.

CONCLUSIONS AND IMPLICATIONS

Anthocyanins are metabolized to a structurally diverse range of metabolites that exhibit dynamic kinetic profiles. Understanding the elimination kinetics of these metabolites is key to the design of future studies examining their utility in dietary interventions or as therapeutics for disease risk reduction.

Phenols and Antioxidant Activity in Vitro and in Vivo of Aqueous Extracts Obtained by Ultrasound-Assisted Extraction from Artichoke By-Products

Artichoke by-products are rich in phenolic compounds although they represent a waste for the food industry. This paper examines the application of ultrasound-assisted extraction (UAE) for obtaining organic solvent-free extracts rich in nutraceuticals from artichoke scraps. Application of ultrasounds for 60 minutes on test samples, using water as a solvent, improved recovery of phenolic substances compared with untreated samples. Among the phenols detected by high performance liquid chromatography, 5- O-caffeoylquinic and 1,5-di- O-caffeoylquinic acids were identified. In vivo treatments of tobacco BY-2 cells with ultrasonic extracts consistently enhanced their antioxidant power, making the cells more resistant to heat stress. UAE applied to artichoke by-products, using water as a solvent, appears to be a powerful eco-friendly technique that can provide extracts rich in nutraceuticals and turn waste products into resources. The extracts could be advantageously utilized in the food industry to produce functional foods.

Impact of processing on the bioavailability and vascular effects of blueberry (poly)phenols

SCOPE

Blueberries are a rich source of flavonoids and phenolic acids. Currently, little information is available regarding the impact of processing on the bioavailability and the bioactivity of blueberry (poly)phenols.

METHODS AND RESULTS

In a randomized, controlled crossover trial, ten healthy volunteers consumed (a) blueberry-containing baked products, (b) an unprocessed blueberry drink containing the same amount of freeze-dried blueberry powder as used in the baked products, and (c) matched control baked products. Endothelial function was measured as flow-mediated dilation (FMD) and plasma samples taken at baseline and at 1, 2, 4, and 6 h postconsumption. Although processing did not significantly change the total (poly)phenolic amount, the processed products contained significantly less anthocyanins (-42%), more chlorogenic acid (23%), no flavanol nonamers or decamers, and significantly more flavanol dimers and trimers (36% and 28%, respectively). FMD increased after 1, 2, and 6 h consumption of the baked products to a similar degree as the unprocessed blueberries, despite significant differences in the levels of individual plasma metabolites. No changes were observed after the consumption of the control product.

CONCLUSION

Careful processing can preserve important biological activities of blueberries despite changing the blueberry (poly)phenol composition and plasma metabolite profile.

Artichoke, cynarin and cyanidin downregulate the expression of inducible nitric oxide synthase in human coronary smooth muscle cells

Artichoke (Cynara scolymus L.) is one of the world’s oldest medicinal plants with multiple health benefits. We have previously shown that artichoke leaf extracts and artichoke flavonoids upregulate the gene expression of endothelial-type nitric oxide synthase (eNOS) in human endothelial cells. Whereas NO produced by the eNOS is a vasoprotective molecule, NO derived from the inducible iNOS plays a pro-inflammatory role in the vasculature. The present study was aimed to investigate the effects of artichoke on iNOS expression in human coronary artery smooth muscle cells (HCASMC). Incubation of HCASMC with a cytokine mixture led to an induction of iNOS mRNA expression. This iNOS induction was concentration- and time-dependently inhibited by an artichoke leaf extract (1–100 µg/mL, 6 h or 24 h). Consistently, the artichoke leaf extract also reduced cytokine-induced iNOS promoter activation and iNOS protein expression. In addition, treatment of HCASMC with four well-known artichoke compounds (cynarin > cyanidin > luteolin ≈ cynaroside) led to a downregulation iNOS mRNA and protein expression, with cynarin being the most potent one. In conclusion, artichoke contains both eNOS-upregulating and iNOS-downregulating compounds. Such compounds may contribute to the beneficial effects of artichoke and may per se have therapeutic potentials.