Orally administered delphinidin 3-rutinoside and cyanidin 3-rutinoside are directly absorbed in rats and humans and appear in the blood as the intact forms

Weak Inhibitory Effects of Anthocyanins on Human Aldehyde Oxidase Activity: An In Vitro Study

Aldehyde oxidase (AO) plays an important role in the metabolism of antitumor and antiviral drugs, including methotrexate, favipiravir, and acyclovir. The consumption of blueberry fruits or their extracts, which contain large amounts of anthocyanins, has recently increased. The intake of large amounts of anthocyanins occurs through the frequent consumption of blueberries or their functional foods, which may result in unwanted interactions between anthocyanins and medicinal drugs. Therefore, the present study examined the inhibition of AO by anthocyanins, anthocyanidins, and blueberry extracts in human liver cytosol using a HPLC assay. A comparison of the 50% inhibitory concentration (IC₅₀) values of the test compounds showed that anthocyanidins slightly suppressed AO activity, whereas the inhibitory effects of anthocyanins and blueberry extracts were negligible. The inhibitory activities of the anthocyanins tested were approximately 60- to 130-fold weaker than that of the positive control menadione and were almost negligible. Furthermore, they were approximately 2,000-fold less potent than that of raloxifene, a typical AO inhibitor, and, thus, unlikely to interfere with drug metabolism by AO. In addition, since the plasma concentrations of anthocyanins after their administration were generally lower than the IC₅₀ level, the inhibition of AO substrate metabolism by anthocyanins does not appear to be severe.

Hibiscus sabdariffa anthocyanins are potential modulators of estrogen receptor alpha activity with favourable toxicology: a computational analysis using molecular docking, ADME/Tox prediction, 2D/3D QSAR and molecular dynamics simulation

The estrogen hormone receptor (ER) mediated gene expression mainly regulate the development and physiology of the primary and secondary reproductive system alongside bone-forming, metabolism and behaviour. Over-expressed ER is associated with several pathological conditions and play a crucial role in breast cancer occurrence, progression and metastasis. Hibiscus sabdariffa L. or roselle is a rich source of naturally occurring polyphenolic compounds that reportedly have robust estrogenic activity. However, the estrogen-like ingredient of the plant remains ambiguous. This study has screened a library of already recorded and less-explored compounds of Hibiscus sabdariffa for their estrogen receptor binding affinity and safety using a suite of computational methods that include protein-ligand docking, ADME and Toxicity prediction, and 2D/3D QSAR. The study revealed that the estrogen-receptor binding potential of Pelargonidin, Delphinidin, Cyanidin, and Hibiscetin are more efficient than popular breast cancer drugs, Tamoxifen and Raloxifene. Besides, the compounds exhibited favourable toxicological parameters with potent bioactivity towards binding ER-α subunit. Thus, these compounds can serve as prototypes for designing novel Selective Estrogen Receptor Modulator molecules with a few structural modifications. This is the first report exploring the phytochemical basis of estrogenic activity of Hibiscus sabdariffa L.Communicated by Ramaswamy H. Sarma.

Delphinidin-3-O-glucoside in vitro suppresses NF-κB and changes the secretome of mesenchymal stem cells affecting macrophage activation

OBJECTIVE

Anthocyanins are polyphenols that are promising chemopreventive agents. They stand out for their anti-inflammatory properties, with specific modulatory actions on the immune system. Additionally, regarding the immune system, a group of cells identified as mesenchymal stem cells (MSCs) have been attracting attention, mainly because of their capacity to migrate to sites of inflammation and produce potent immunomodulatory effects. Considering the ability of these cells to act on the immune system, as well as the properties of anthocyanins, especially delphinidin, in modulating the immune system, the aim of this study was to investigate the effects of delphinidin in influencing some immunoregulatory properties of MSCs.

METHODS

MSCs were cultivated in the presence of delphinidin 3-O-β-d-glycoside and cell viability, the cell cycle and the production of soluble factors (interleukin [IL]-1β, IL-6, IL-10, transforming growth factor [TGF]-β, prostaglandin E₂ [PGE₂] and nitric oxide [NO]) were evaluated, as was the expression of the transcription factors nuclear factor (NF)-κB and STAT3. Additionally, the effects of conditioned media from MSCs on macrophage activation were assessed.

RESULTS

Delphinidin at 50 µM does not affect cell viability. In association with lipopolysaccharide, delphinidin was able to induce MSC proliferation. Additionally, delphinidin modulated the MSC immune response, showing increased levels of anti-inflammatory cytokines such as IL-10 and TGF-β as well as lower expression of NF-κB. Furthermore, conditioned media from MSCs inhibited macrophage metabolism, reducing the production of IL-1β, IL-12, and TNF-α and increasing IL-10.

CONCLUSIONS

Overall, this work showed that delphinidin can modify the immunomodulatory properties of MSCs, increasing the IL-10 production by macrophages.

Research Progress on Absorption, Metabolism, and Biological Activities of Anthocyanins in Berries: A Review

Berries, as the best dietary sources for human health, are rich in anthocyanins, vitamins, fiber, polyphenols, essential amino acids, and other ingredients. Anthocyanins are one of the most important bioactive components in berries. The attractive color of berries is attributed to the fact that berries contain different kinds of anthocyanins. Increasing research activity has indicated that anthocyanins in berries show various biological activities, including protecting vision; antioxidant, anti-inflammatory and anti-tumor qualities; inhibition of lipid peroxidation; anti-cardiovascular disease properties; control of hypoglycemic conditions; and other activities. Hence, berries have high nutritional and medicinal values. The recognized absorption, metabolism, and biological activities of anthocyanins have promoted their research in different directions. Hence, it is necessary to systematically review the research progress and future prospects of anthocyanins to promote a better understanding of anthocyanins. The absorption, metabolism, and biological activities of anthocyanins from berries were reviewed in this paper. The findings of this study provide an important reference for basic research, product development and utilization of berries' anthocyanins in food, cosmetics, and drugs.

Distribution, Antioxidant Capacity, Bioavailability and Biological Properties of Anthocyanin Pigments in Blood Oranges and Other Citrus Species

Anthocyanins are natural pigments that give a red, purple, and blue color to many plant, flower, fruit, and vegetable species. Their presence within the genus Citrus was first reported in 1916, and it is well-known that the red color of the flesh and rind of blood (red or pigmented) oranges (Citrus sinensis L. Osbeck) is due to the presence of anthocyanins. They are also present in the young shoots, flowers, and peel of lemon (Citrus limon (L.) Burm. f.), citron (Citrus medica L.), and other citrus species. Since then, the scientific community has expressed increasing interest in studying their profile and distribution, with many published studies focused on the quali-quantitative pattern in the different vegetative tissues belonging to the genus Citrus. Moreover, with the discovery of their relevant antioxidant activity, owing to their ability to capture free radicals, much research has been performed in the last two decades on their radical scavenging power, in vitro and in vivo biological properties, and anticarcinogenic capacity, also focusing attention on their bioavailability for humans. The present work is intended as a comprehensive review of the advances in scientific research on anthocyanin pigments naturally occurring within the genus Citrus, including their natural distribution, antioxidant capacity, bioavailability, and biological value and properties. The scientific evidence herein reported can be used to further increase the knowledge of this class of compounds and represents a valuable and comprehensive contribution to promoting anthocyanin-rich citrus fruit consumption as a healthy dietary habit.

Interactions between dietary flavonoids and the gut microbiome: a comprehensive review

Flavonoids are natural polyphenol secondary metabolites that are widely produced in planta. Flavonoids are ubiquities in human dietary intake and exhibit a myriad of health benefits. Flavonoids-induced biological activities are strongly influenced by their in situ availability in the human GI tract, as well as the levels of which are modulated by interaction with the gut bacteria. As such, assessing flavonoids–microbiome interactions is considered a key to understand their physiological activities. Here, we review the interaction between the various classes of dietary flavonoids (flavonols, flavones, flavanones, isoflavones, flavan-3-ols and anthocyanins) and gut microbiota. We aim to provide a holistic overview of the nature and identity of flavonoids on diet and highlight how flavonoids chemical structure, metabolism and impact on humans and their microbiomes are interconnected. Emphasis is placed on how flavonoids and their biotransformation products affect gut microbiota population, influence gut homoeostasis and induce measurable physiological changes and biological benefits.

Onion anthocyanins: Extraction, stability, bioavailability, dietary effect, and health implications

Anthocyanins are high-value compounds, and their use as functional foods and their natural colorant have potential health benefits. Anthocyanins seem to possess antioxidant properties, which help prevent neuronal diseases and thereby exhibit anti-inflammatory, chemotherapeutic, cardioprotective, hepatoprotective, and neuroprotective activities. They also show different therapeutic effects against various chronic diseases. Anthocyanins are present in high concentrations in onion. In recent years, although both conventional and improved methods have been used for extraction of anthocyanins, nowadays, improved methods are of great importance because of their higher yield and stability of anthocyanins. In this review, we compile anthocyanins and their derivatives found in onion and the factors affecting their stability. We also analyze different extraction techniques of anthocyanins. From this point of view, it is very important to be precisely aware of the impact that each parameter has on the stability and subsequently potentiate its bioavailability or beneficial health effects. We present up-to-date information on bioavailability, dietary effects, and health implications of anthocyanins such as antioxidant, antidiabetic, anticancerous, antiobesity, cardioprotective, and hepatoprotective activities.

Chemical Compounds of Berry-Derived Polyphenols and Their Effects on Gut Microbiota, Inflammation, and Cancer

Berry-derived polyphenols are bioactive compounds synthesized and secreted by several berry fruits. These polyphenols feature a diversity of chemical compounds, including phenolic acids and flavonoids. Here, we report the beneficial health effects of berry-derived polyphenols and their therapeutical application on gut-microbiota-related diseases, including inflammation and cancer. Pharmacokinetic investigations have confirmed the absorption, availability, and metabolism of berry-derived polyphenols. In vitro and in vivo tests, as well as clinical trials, showed that berry-derived polyphenols can positively modulate the gut microbiota, inhibiting inflammation and cancer development. Indeed, these compounds inhibit the growth of pathogenic bacteria and also promote beneficial bacteria. Moreover, berry-derived polyphenols exhibit therapeutic effects against different gut-microbiota-related disorders such as inflammation, cancer, and metabolic disorders. Moreover, these polyphenols can manage the inflammation via various mechanisms, in particular the inhibition of the transcriptional factor Nf-κB. Berry-derived polyphenols have also shown remarkable effects on different types of cancer, including colorectal, breast, esophageal, and prostate cancer. Moreover, certain metabolic disorders such as diabetes and atherosclerosis were also managed by berry-derived polyphenols through different mechanisms. These data showed that polyphenols from berries are a promising source of bioactive compounds capable of modulating the intestinal microbiota, and therefore managing cancer and associated metabolic diseases. However, further investigations should be carried out to determine the mechanisms of action of berry-derived polyphenol bioactive compounds to validate their safety and examinate their clinical uses.

The Effects of Berry Extracts on Oxidative Stress in Cultured Cardiomyocytes and Microglial Cells: A Potential Cardioprotective and Neuroprotective Mechanism

Oxidative stress is a key underlying factor in cognitive decline and atherosclerosis. Oxidative stress occurs at the cellular level with an imbalance between reactive oxygen species and reactive nitrogen species and a deficiency in antioxidants. Mounting evidence suggests that berry flavonoids may promote cellular health by exerting antioxidant properties. Black currant and various berry extracts were tested in microglia (BV-2) and cardiomyocyte (HL-1) cell lines to study their biological effects. The principal ingredients in black currant and cranberry extract–delphinidin 3-rutinoside (D3R) and cyanidin 3-glucoside (C3G), were also assessed. A menadione-induced oxidative stressor was used, and its output was quantified to detect oxidative stress (CellROX^TM). Black currant extract had similar antioxidant effects as N-acetylcysteine (NAC) in HL-1 cells with regard to cellular protection, whereas cranberry extract was ineffective. In contrast, cranberry extract was comparable in effectiveness to black currant extract in BV-2 cells. D3R and C3G also reduced oxidative stress similarly to whole berry extracts, which indicates that these ingredients may confer the antioxidant effects of berries. Black currant and cranberry extracts inhibit oxidative stress in microglial and cardiomyocyte cell lines. Black currant extract was more effective in reducing oxidative stress in the HL-1 cells, whereas cranberry extract was comparable in reducing oxidative stress in the BV-2 cells. The results suggest that berry flavonoids exert neuro- and cardioprotective effects.

Chemistry and Pharmacological Actions of Delphinidin, a Dietary Purple Pigment in Anthocyanidin and Anthocyanin Forms

Anthocyanins are naturally occurring water-soluble flavonoids abundantly present in fruits and vegetables. They are polymethoxyderivatives of 2-phenyl-benzopyrylium or flavylium salts. Delphinidin (Dp) is a purple-colored plant pigment, which occurs in a variety of berries, eggplant, roselle, and wine. It is found in a variety of glycosidic forms ranging from glucoside to arabinoside. Dp is highly active in its aglycone form, but the presence of a sugar moiety is vital for its bioavailability. Several animal and human clinical studies have shown that it exerts beneficial effects on gut microbiota. Dp exhibits a variety of useful biological activities by distinct and complex mechanisms. This manuscript highlights the basic characteristics, chemistry, biosynthesis, stability profiling, chemical synthesis, physicochemical parameters along with various analytical methods developed for extraction, isolation and characterization, diverse biological activities and granted patents to this lead anthocyanin molecule, Dp. This review aims to open pathways for further exploration and research investigation on the true potential of the naturally occurring purple pigment (Dp) in its anthocyanidin and anthocyanin forms beyond nutrition.

Ornamental Flowers Grown in Human Surroundings as a Source of Anthocyanins with High Anti-Inflammatory Properties

Flowers have always accompanied people thanks to their manifold aesthetic properties. Some species have also become a component of the human diet. Recent years have seen an increased interest in edible flowers and, consequently, research has been undertaken to determine their chemical composition. Dyes that are abundantly contained in flowers, whose role is to attract pollinating animals, are recognized substances with health-promoting properties. Anthocyanins are a group of dyes that are very common in petals and other parts of flowers. Studies carried out in the twentieth and twenty-first century on flowers growing in temperate climates have found very strong antioxidant and anti-inflammatory properties of anthocyanins. Therefore, flowers used by humans for centuries to decorate their surroundings may become an easily available source of nutrients and health-promoting substances. This paper discusses the health-promoting properties of anthocyanins and collects literature on anthocyanin content in edible flowers commonly grown on balconies, terraces, and roofs in countries of temperate climate.

Nanotechnology as a Tool to Mitigate the Effects of Intestinal Microbiota on Metabolization of Anthocyanins

Anthocyanins are an important group of phenolic compounds responsible for pigmentation in several plants. For humans, a regular intake is associated with a reduced risk of several diseases. However, molecular instability reduces the absorption and bioavailability of these compounds. Anthocyanins are degraded by external factors such as the presence of light, oxygen, temperature, and changes in pH ranges. In addition, the digestion process contributes to chemical degradation, mainly through the action of intestinal microbiota. The intestinal microbiota has a fundamental role in the biotransformation and metabolization of several dietary compounds, thus modifying the chemical structure, including anthocyanins. This biotransformation leads to low absorption of intact anthocyanins, and consequently, low bioavailability of these antioxidant compounds. Several studies have been conducted to seek alternatives to improve stability and protect against intestinal microbiota degradation. This comprehensive review aims to discuss the existing knowledge about the structure of anthocyanins while discussing human absorption, distribution, metabolism, and bioavailability after the oral consumption of anthocyanins. This review will highlight the use of nanotechnology systems to overcome anthocyanin biotransformation by the intestinal microbiota, pointing out the safety and effectiveness of nanostructures to maintain molecular stability.

Current Knowledge on Intestinal Absorption of Anthocyanins

Anthocyanins are flavonoid compounds that are natural color pigments occurring in various colored plants, such as berry fruits, vegetables, and grapes. With the elucidation of their various physiological effects, anthocyanins have been identified as promising functional food ingredients. However, findings on the bioavailability of anthocyanins, which are present in various chemical structures in foods, are limited; their intestinal absorption behaviors, including their transport route(s), have not been fully explained. This perspective overviews the current knowledge and issues and discusses advanced techniques, such as in situ matrix-assisted laser desorption/ionization mass spectrometry imaging, and future perspectives on the study of the bioavailability of anthocyanins.

Enhancement of the Colorectal Chemopreventive and Immunization Potential of Northern Thai Purple Rice Anthocyanin Using the Biotransformation by β-Glucosidase-Producing Lactobacillus

This study aimed to study the biotransformation of indigenous northern Thai purple rice using β-glucosidase-producing Lactobacillus (BGPL) to increase the content of bioactive anthocyanin for colorectal chemoprevention and immunization. BGPL, namely, Lactobacillus FR 332, was first isolated from Thai fermented foods. Indigenous northern Thai purple rice, namely, Khao’ Gam Leum-Phua (KGLP), was selected to study bioactive anthocyanin using biotransformation by L. plantarum FR332 according to the highest amounts of cyanidin-3-glucoside. The determination of anthocyanin quantities revealed that the highest cyanidin was detected after 12 h of biotransformation, corresponding to the highest β-glucosidase activity of L. plantarum FR332 and a decrease in cyanidin-3-glucoside. The anthocyanin extract, after 12 h of biotransformation, exhibited the most potent in vitro antioxidative activity. Additionally, it showed potent anti-inflammatory activity by inhibiting cyclooxygenase-2 (COX-2), nitric oxide, and inducible nitric oxide synthase (iNOS) production in interferon-γ-stimulated colon adenocarcinoma (HT-29) cells without exerting cytotoxicity. Moreover, it also showed a potent inhibitory effect on proinflammatory cytokine interleukin-6 (IL-6) secretion and an induction effect on anti-inflammatory cytokine IL-10 secretion. These documents highlight the potential to be used of the anthocyanin extract after 12 h of biotransformation by L. plantarum FR332 as a natural active pharmaceutical ingredient (NAPI) for colorectal chemoprevention and immunization.

Cyanidin-3-rutinoside stimulated insulin secretion through activation of L-type voltage-dependent Ca2+ channels and the PLC-IP3 pathway in pancreatic β-cells

Cyanidin-3-rutinoside (C3R) is an anthocyanin with anti-diabetic properties found in red-purple fruits. However, the molecular mechanisms of C3R on Ca²⁺-dependent insulin secretion remains unknown. This study aimed to identify C3R's mechanisms of action in pancreatic β-cells. Rat INS-1 cells were used to elucidate the effects of C3R on insulin secretion, intracellular Ca²⁺ signaling, and gene expression. The results showed that C3R at 60, 100, and 300 µM concentrations significantly increased insulin secretion via intracellular Ca²⁺ signaling. The exposure of cells with C3R concentrations up to 100 μM did not affect cell viability. Pretreatment of cells with nimodipine (voltage-dependent Ca²⁺ channel (VDCC) blocker), U73122 (PLC inhibitor), and 2-APB (IP₃ receptor blocker) inhibited the intracellular Ca²⁺ signals by C3R. Interestingly, C3R increased intracellular Ca²⁺ signals and insulin secretion after depletion of endoplasmic reticulum Ca²⁺ stores by thapsigargin. However, insulin secretion was abolished under extracellular Ca²⁺-free conditions. Moreover, C3R upregulated mRNA expression for Glut2 and Kir_6.2 genes. These findings indicate that C3R stimulated insulin secretion by promoting Ca²⁺ influx via VDCCs and activating the PLC-IP₃ pathway. C3R also upregulates the expression of genes necessary for glucose-induced insulin secretion. This is the first study describing the molecular mechanisms by which C3R stimulates Ca²⁺-dependent insulin secretion from pancreatic β-cells. These findings contribute to our understanding on how anthocyanins improve hyperglycemia in diabetic patients.

Delphinidin diminishes in vitro interferon-γ and interleukin-17 producing cells in patients with psoriatic disease

The anthocyanidin delphinidin reduces psoriasiform lesions and inflammatory mediators in human cell culture systems. Its role in psoriatic disease has not yet been investigated. We assessed delphinidin's in vitro immunomodulatory effect on ex vivo stimulated peripheral blood mononuclear cells (PBMCs) from 50 individuals [26 with psoriasis, 10 with psoriatic arthritis (PsA) and 14 healthy controls (HCs)]. Cells were either left untreated or stimulated with PMA plus ionomycin in the presence or absence of delphinidin. Intracellular production of interferon-γ (IFNγ), interleukin-17A (IL-17A), and interleukin-10 (IL-10) was measured flow cytometrically. Delphinidin dose-dependently reduced IFNγ⁺ T cells from patients and HCs. The mean IFNγ decrease in CD4⁺ T subpopulations was 42.5 ± 28% for psoriasis patients, 51.8 ± 21.5% for PsA patients and 49 ± 17% for HCs (p < 0.001 for all). Similarly, IFNγ reduction in CD8⁺ T cells was 34 ± 21.6% for psoriasis patients, 47.1 ± 22.8% for PsA and 44.8 ± 14.3% for HCs (P < 0.001 for all). An inhibitory effect of delphinidin was also noted in IFNγ producing NKs and NKTs from psoriasis individuals. Delphinidin also significantly decreased IL-17⁺ CD4⁺ T cells in all tested subjects, with marginal effect on the increase of IL-10-producing T regulatory subsets. In conclusion, delphinidin exerts a profound in vitro anti-inflammatory effect in psoriasis and psoriatic arthritis by inhibiting IFNγ⁺ innate and adaptive cells and T helper (Th) 17 cells. If this effect is also exerted in vivo, delphinidin may be regarded as a nutraceutical with immunosuppressive potential.

Adduct Formation of Acrolein with Cyanidin-3-O-glucoside and Its Degradants/Metabolites during Thermal Processing or In Vivo after Consumption of Red Bayberry

Acrolein (ACR) derives from the external environment and the endogenous metabolism of organisms. It has super-reactivity and can induce various diseases. We investigated the capacity of cyanidin-3-O-glucoside (C3G) and its degradants/metabolites to capture ACR during thermal processing or in vivo. Our results indicated that both C3G and its degradants, including phloroglucinaldehyde (PGA) and protocatechuic acid (PCA), could efficiently trap ACR to form adducts, such as C3G-ACR, C3G-2ACR, PGA-ACR, PGA-2ACR, PCA-ACR, and PCA-2ACR. Additionally, these adducts were detected in commercial canned red bayberry products. The adducts of C3G and its metabolites conjugated with ACR, such as C3G-ACR, C3G-2ACR, PGA-ACR, and 4-hydroxybenzoic-acid-ACR (4-HBA-ACR), were also detected in mice feces treated with C3G by oral gavage, where the adduct level was dose-dependent. A similar pattern was observed in tests on human consumption of red bayberry. In human urine, only PGA-2ACR and 4-HBA-ACR, were found, whereas C3G-ACR, C3G-2ACR, myricetin-3-O-rhamnoside-ACR (M3R-ACR), PGA-2ACR, 4-HBA-ACR and ferulic acid-ACR (FA-ACR) were detected in human feces following administration of red bayberry. Our results are the first demonstration that C3G and its metabolites can capture ACR in vitro and in vivo (mice and humans) and present a novel strategy, the development of C3G as a promising ACR inhibitor.

Cellular uptake of anthocyanins extracted from black soybean, grape, and purple sweet potato using INT-407 cells

This study combined in vitro digestion and INT-407 cells to evaluate the bioaccessibility of anthocyanins in the small intestinal epithelial cells. Black soybean, grape, and purple sweet potato were chosen as they have a different anthocyanin composition. After the aqueous extract was digested under in vitro gastric and intestinal conditions, the digested mixture was incubated in the media of INT-407 for 2 h at 37 °C. Low proportion (< 0.3%) of anthocyanins in black soybean and grape passed through cell membranes. Cyanidin-3-O-glucoside and pelargonidin-3-O-glucoside in black soybean and cyanidin-3-O-(6-O-p-coumaroyl)-5-O-diglucoside and delphinidin-3-O-(6-O-p-coumaroyl)-5-O-diglucoside in grape were found inside the cell. However, acylated anthocyanins containing three sugar moieties in purple sweet potato were not detected inside the cell. p-Coumaric acid was detected in the cells incubated with grape, but not in the media. These indicate that chemical structure of anthocyanins affected their cellular uptake and antioxidant activity in INT-407 cells.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-021-00976-y.

Potential micro-/nano-encapsulation systems for improving stability and bioavailability of anthocyanins: An updated review

Anthocyanins (ACNs) are notable hydrophilic compounds that belong to the flavonoid family, which are available in plants. They have excellent antioxidants, anti-obesity, anti-diabetic, anti-inflammatory, anticancer activity, and so on. Furthermore, ACNs can be used as a natural dye in the food industry (food colorant). On the other hand, the stability of ACNs can be affected by processing and storage conditions, for example, pH, temperature, light, oxygen, enzymes, and so on. These factors further reduce the bioavailability (BA) and biological efficacy of ACNs, as well as limit ACNs application in both food and pharmaceutics field. The stability and BA of ACNs can be improved via loading them in encapsulation systems including nanoemulsions, liposomes, niosomes, biopolymer-based nanoparticles, nanogel, complex coacervates, and tocosomes. Among all systems, biopolymer-based nanoparticles, nanohydrogels, and complex coacervates are comparatively suitable for improving the stability and BA of ACNs. These three systems have excellent functional properties such as high encapsulation efficiency and well-stable against unfavorable conditions. Furthermore, these carrier systems can be used for coating of other encapsulation systems (such as liposome). Additionally, tocosomes are a new system that can be used for encapsulating ACNs. ACNs-loaded encapsulation systems can improve the stability and BA of ACNs. However, further studies regarding stability, BA, and in vivo work of ACNs-loaded micro/nano-encapsulation systems could shed a light to evaluate the therapeutic efficacy including physicochemical stability, target mechanisms, cellular internalization, and release kinetics.

Acylated anthocyanins: A review on their bioavailability and effects on postprandial carbohydrate metabolism and inflammation

Anthocyanins, the natural red and purple colorants of berries, fruits, vegetables, and tubers, improve carbohydrate metabolism and decrease the risk factors of metabolic disorders, but their industrial use is limited by their chemical instability. Acylation of the glycosyl moieties of anthocyanins, however, changes the chemical properties of anthocyanins and provides enhanced stability. Thus, acylated anthocyanins are more usable as natural colorants and bioactive components of innovative functional foods. Acylated anthocyanins are common in pigmented vegetables and tubers, the consumption of which has the potential to increase the intake of health-promoting anthocyanins as part of the daily diet. For the first time, this review presents the current findings on bioavailability, absorption, metabolism, and health effects of acylated anthocyanins with comparison to more extensively investigated nonacylated anthocyanins. The structural differences between nonacylated and acylated anthocyanins lead to enhanced color stability, altered absorption, bioavailability, in vivo stability, and colonic degradation. The impact of phenolic metabolites and their potential health effects regardless of the low bioavailability of the parent anthocyanins as such is discussed. Here, purple-fleshed potatoes are presented as a globally available, eco-friendly model food rich in acylated anthocyanins, which further highlights the industrial possibilities and nutritional relevance of acylated anthocyanins. This work supports the academic community and industry in food research and development by reviewing the current literature and highlighting gaps of knowledge.

Evaluation of Blood-Brain Barrier Permeability of Polyphenols, Anthocyanins, and Their Metabolites

Anthocyanins (ACs) are able to protect neurons against β-amyloid-induced neurotoxicity. In this study, we evaluated blood-brain barrier (BBB) permeability of these compounds using a model kit to clarify the mechanism of AC on the brain. Black currant or strawberry AC extract was orally administrated to male Wistar rats. The urine and extirpated brain were collected before and after administration and analyzed quantitatively by liquid chromatography-tandem mass spectrometry. After administration of AC, several phenolic acids were detected in the urine samples. Further, AC and some AC metabolites were found in the brain tissue. BBB permeabilities of these compounds were much lower than the positive control. Epigallocatechin, daidzein, genistein, equol, and nobiletin presented high BBB permeability, whereas apigenin, luteolin, quercetin, and kaempferol showed medium permeability, and epicatechin, rutin, fisetin, resveratrol, and curcumin BBB permeation was neglected. These results suggested that ACs were difficult to cross BBB into the brain and ACs were not directly associated with the prevention of β-amyloid-induced neurotoxicity.

The Role of Anthocyanins in Drug Discovery: Recent Developments

Natural compounds have always played a key role in drug discovery. Anthocyanins are secondary metabolites belonging to the flavonoids family responsible for the purple, blue, and red colour of many vegetables and fruits. These phytochemicals have attracted the interest of researchers for their important implications in human health and for their use as natural colorants. Many in vitro and in vivo studies demonstrated the potential effects of anthocyanins and anthocyanins-rich foods in the prevention and/or treatment of diabetes, cancer, and cardiovascular and neurodegenerative diseases. This review reports the recent literature data and focuses on the potential role of anthocyanins in drug discovery. Their biological activity, analysis of structure-activity relationships, bioavailability, metabolism, and future prospects of their uses are critically described.

Genus Ribes Linn. (Grossulariaceae): A comprehensive review of traditional uses, phytochemistry, pharmacology and clinical applications

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Ribes Linn., which belongs to the Grossulariaceae family, contains 160 species distributed mainly in temperate and cold regions of the Northern Hemisphere. There are 59 species in southwest, northwest and northeast China. Some species of Ribes have been used as traditional and local medicines for the treatment of glaucoma, cardiovascular disease, stomachache, hepatitis, hyperlipidemia, hypertension and other ailments. However, the data provided in recent years have not been collated and compared.

AIM OF THE STUDY

This review aims to summarize the current status of ethnopharmacological uses, phytochemistry, pharmacology, clinical applications, and pharmacokinetics of the genus Ribes to better understand the therapeutic potential of the genus Ribes in the future and hope to provide a relatively novel perspective for further clinical application on the genus.

MATERIALS AND METHODS

The literature on Ribes was collected through a series of scientific search engines including Elsevier, ACS, Springer, Web of Science, PubMed, Google Scholar, Baidu Scholar, Wiley, China National Knowledge Infrastructure (CNKI) and books.

RESULTS

Ribes species have been used for detoxification, glaucoma, cardiovascular disease, stomachache, hepatitis, hyperlipidemia, hypertension and other ailments. These plants mainly contain phenolic glycosides, flavonoids, proanthocyanidins, polysaccharides, etc. Most traditional uses are related to biological activity and have been confirmed by modern research. Pharmacological studies in vitro and in vivo revealed that the extracts and pure compounds possessed significant hypolipidemic, antioxidant, anti-inflammatory, antitumor, antibacterial, and antiviral activity, eyesight protection and other effects.

CONCLUSIONS

The traditional uses, phytochemistry, pharmacology, pharmacokinetics, and clinical applications described in this article explained that the Ribes species has numerous activities, and these findings will promote further action in the area of mechanism research. However, very few preclinical and clinical studies have focused on the toxicology and pharmacokinetics of crude extracts and pure compounds from the genus Ribes. Moreover, several clinical evidence to support the health benefits of Ribes plants. The development of new medicines based on Ribes species as ingredients may be restricted. The pharmacological activity, clinical efficacy and safety of Ribes species need to be verified by systematic and comprehensive preclinical studies and clinical trials.

Bioavailability, Absorption, and Metabolism of Pelargonidin-Based Anthocyanins Using Sprague-Dawley Rats and Caco-2 Cell Monolayers

The present study is aimed to clarify the absorption and metabolism properties of pelargonidin-based anthocyanins. Results showed that pelargonidin-3-O-rutinoside (Pg3R) was absorbed in its intact form after oral administration and reached a maximum plasma concentration of 175.38 ± 55.95 nM at 60 min. Three main metabolites were identified in plasma, including Pg3R-monoglucuronide (m/z 755.2046), Pg3R-hydroxylated (m/z 595.1644), and Pg3R-demethylated (m/z 565.1569) metabolites. The plasma concentration of the Pg3R-demethylated metabolite (57.04 ± 23.15 nM) was much higher than that of other two metabolites, indicating that demethylation was the main metabolic pathway for Pg3R, while the glucuronide conjugate was detected as the dominant metabolic form of pelargonidin-3-O-glucoside (Pg3G). The bioavailability of Pg3R (1.13%) was fourfold higher than that of Pg3G (0.28%), demonstrating that anthocyanins linked to the rutinoside may exhibit higher bioavailability than that of glucoside. In vitro transport study unveiled that passive diffusion and active efflux were involved in the absorption of Pg3R and Pg3G.

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.

Chemical composition, bioactive compounds extraction, and observed biological activities from jussara (Euterpe edulis): The exotic and endangered Brazilian superfruit

In this article, we reviewed studies on the fruits of the jussara palm (Euterpe edulis Martius), an endangered Brazilian Atlantic Forest palm tree, also coined as "Superfruit." We summarized the chemical components of the pulp and observed biological activities in murine and humans, as well as the best practices involving the extraction of its target compounds, bioavailability, and stability of extracts. Jussara has shown a rich phenolic profile that justifies its antioxidant properties, in addition to a considerable lipidic and energetic value. As the main feature, the fruit possesses large amounts of anthocyanins that can be commercially explored as a food additive or cosmetic colorants. Recent studies emphasized jussara's antioxidant, anti-inflammatory, and cardioprotective capabilities via reshaping of the gut microbiota. Further knowledge is needed to establish bioavailability and optimal serving size, as many of its antioxidant compounds go under chemical bioconversion in the intestinal tract. While extraction of phenolic compounds, anthocyanins, and oils have interesting results, more studies are required in order to reduce the use of conventional organic solvents and improve their stability and shelf life when added to food products, an area in which nanotechnology seems promising.

Plasma uptake of selected phenolic acids following New Zealand blackcurrant extract supplementation in humans

New Zealand blackcurrant (NZBC) extract is a rich source of anthocyanins and in order to exert physiological effects, the anthocyanin-derived metabolites need to be bioavailable in vivo. We examined the plasma uptake of selected phenolic acids following NZBC extract supplementation alongside maintaining a habitual diet (i.e. not restricting habitual polyphenol intake). Twenty healthy volunteers (nine females, age: 28 ± 7 years, height 1.73 ± 0.09 m, body mass 73 ± 11 kg) consumed a 300 mg NZBC extract capsule (CurraNZ^®; anthocyanin content 105 mg) following an overnight fast. Venous blood samples were taken pre and 1, 1.5, 2, 3, 4, 5, and 6 h post-ingestion of the capsule. Reversed-phase high-performance liquid chromatography (HPLC) was used for analysis of two dihydroxybenzoic acids [i.e. vanillic acid (VA) and protocatechuic acid (PCA)] and one trihydroxybenzoic acid [i.e. gallic acid (GA)] in plasma following NZBC extract supplementation. Habitual anthocyanin intake was 168 (95%CI:68-404) mg⋅day^-1 and no associations were observed between this and VA, PCA, and GA plasma uptake by the NZBC extract intake. Plasma time-concentration curves revealed that GA, and PCA were most abundant at 4, and 1.5 h post-ingestion, representing a 261% and 320% increase above baseline, respectively, with VA remaining unchanged. This is the first study to demonstrate that an NZBC extract supplement increases the plasma uptake of phenolic acids GA, and PCA even when a habitual diet is followed in the days preceding the experimental trial, although inter-individual variability is apparent.

Biological activities of açaí (Euterpe oleracea Mart.) and juçara (Euterpe edulis Mart.) intake in humans: an integrative review of clinical trials

Açaí (E. oleracea) and juçara (E. edulis) are berries considered a source of bioactive compounds, especially anthocyanins and unsaturated fatty acids, with recognized health-promoting activities. An integrative review was conducted to identify available clinical trials that evaluated the effects of açaí and juçara intake on the human organism. Science Direct and Medline databases were searched. Human studies that evaluated any biological activities after açaí and juçara intake were included in this review. Twenty-three clinical trials were identified up to April 12, 2020. Studies evaluated the biological effects of açaí (n = 17), juçara (n = 5), or both berries simultaneously (n = 1). The results of these trials suggest both types of berries may contribute to improved antioxidant defense and to attenuating metabolic stress and inflammation. However, considerable heterogeneity was observed among trials, and few studies explored the bioactive compounds of the food matrix provided in the interventions. More clinical trials are encouraged to strengthen the current evidence on human biological outcomes, including comparative analysis between these berries.

Matrix-assisted laser desorption/ionization mass spectrometry-guided visualization analysis of intestinal absorption of acylated anthocyanins in Sprague-Dawley rats

It is unknown whether intestinal absorption of acylated anthocyanins occurs in their intact or metabolized form. In this study, with the aid of matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) imaging, intestinal absorption of acylated anthocyanins was visually investigated. Anthocyanin extracts from purple carrots were orally administered to Sprague-Dawley rats. Acylated cyanidins were absorbed into portal and circulating blood systems in their intact form, and aglycon; cyanidin 3-O-(6-O-feruloyl-β-d-glucopyranosyl)-(1 → 6)-[β-d-xylopyranosyl-(1 → 2)]-β-d-galactopyranoside (Cy3XFGG), and showed a high absorption of 39.3 ± 0.1 pmol/mL-plasma at 60 min after administration. MALDI-MS imaging analysis of the rat jejunum membranes showed that an organic anion transporting polypeptide (OATP) transporter was involved in Cy3XFGG transport, while deacylated anthocyanins were incorporated through both the glucose transporter 2 and OATP routes. In conclusion, acylated anthocyanin, Cy3XFGG, can be absorbed in its intact form through intestinal OATP.

Changes in Phenolic Compounds and Antioxidant Activity of Fruit Musts and Fruit Wines during Simulated Digestion

The content of polyphenols (total phenolic content (TPC)) and the antioxidant activity (AOX) of food products depend on the raw materials used and the technological processes in operation, but transformations of these compounds in the digestive tract are very important. The aim of this study was to determine the TPC, profile of polyphenols, and AOX of apple and blackcurrant musts and wines in order to evaluate the changes occurring in a simulated human digestive system. The research material consisted of apples and blackcurrant, from which musts and fruit wines were obtained. All samples were subjected to three-stage digestion in a simulated human digestive system and then analyzed for the following: TPC (Folin–Ciocalteu method) and profile (HPLC), AOX (method with 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic) acid (ABTS) radical), and for the wines also total extract, volatile acidity (International Organization of Vine and Wine (OIV) method), and sugar profile (HPLC). The antioxidant activity of fruit wines is directly related to the total polyphenol content. Phenolic compounds were transformed during all digestive stages, which led to the formation of compounds with higher antioxidant capacity. The largest increase in polyphenols was observed after the digestive stage in the small intestine. Transformations of phenolic compounds at each digestive stage resulted in the formation of derivatives with higher antioxidant potential.

A molecular docking and molecular dynamics simulation study on the interaction between cyanidin-3-O-glucoside and major proteins in cow's milk

The objective of this study was to investigate the molecular interaction and complex stability of four major cow's milk (CM) proteins (α-LA, β-LG, α_s1 -CA, and β-CA) with cyanidin-3-O-glucoside (C3G) using computational methods. The results of molecular docking analysis revealed that hydrogen bond and hydrophobic interaction were the main binding forces to maintain the stability of the C3G-CM protein complexes. Molecular dynamics simulation results showed that all complexes except for C3G-α_s1 -CA were found to reach equilibrium within 50 ns of simulation. α_s1 -CA and β-CA switched to a more compact conformation after binding with C3G. Additionally, the radius of gyration, number of hydrogen bond, radial distribution function, and interaction energy showed that β-CA is the best C3G carrier protein among the four CM proteins. This study can provide valuable information for CM proteins to serve as C3G delivery carriers. PRACTICAL APPLICATIONS: Anthocyanins (ACNs) are flavonoid-based pigments that play an important functional role in regulating human's health. Cow's milk (CM) proteins are the most representative protein-based carriers that can improve the short-term bioavailability and stability of ACNs. Thus, it is important to study the interactions between ACNs and CM proteins at the molecular level for the development of effective ACNs delivery carriers. Our study showed that caseins (α_s1 -CA and β-CA) had more hydrophobic and hydrogen-bonding sites with cyanidin-3-O-glucoside (C3G) than whey proteins using computational methods. Among the four CM proteins, β-CA was the best C3G carrier protein showing the best interaction stability with C3G. Thus, it is helpful for us to screen effective ACNs carriers from multiple protein sources by computational methods.

Red Carrot Cells Cultured in vitro Are Effective, Stable, and Safe Ingredients for Skin Care, Nutraceutical, and Food Applications

Plant biomasses growing in bioreactor could be developed as production systems for cosmetic ingredients, nutraceuticals and food additives. We previously reported that the red carrot cell line R4G accumulates high levels of anthocyanins, which are potent antioxidants with multiple health-promoting properties. To investigate the industrial potential of this cell line in detail, we tested extract for antioxidant and anti-inflammatory activity in the mouse monocyte/macrophage cell-line J774A.1 and in reconstructed skin tissue models. We also compared the R4G extract to commercial carrot extracts in terms of stability and metabolomic profiles. We found that the R4G extract have potent antioxidant and anti-inflammatory activities, protecting mammalian cells from the oxidative stress triggered by exposure to bacterial lipopolysaccharides and H₂O₂. The extract also inhibited the nuclear translocation of NF-κB in an epidermal skin model, and induced the expression of VEGF-A to promote the microcirculation in a dermal microtissue model. The anthocyanins extracted from R4G cells were significantly more stable than those found in natural red carrot extracts. Finally, we showed that R4G extract has similar metabolomic profile of natural extracts by using a combination of targeted and untargeted metabolomics analysis, demonstrating the safety of R4G carrot cells for applications in the nutraceutical and food/feed industries.

Molecular Mechanisms Underlying the Absorption of Aglycone and Glycosidic Flavonoids in a Caco-2 BBe1 Cell Model

The mechanisms of cellular absorption and transport underlying the differences between flavonoid aglycones and glycosides and the effect of the structural feature are not well established. In this study, aglycone, mono-, and diglycosides of quercetin and cyanidin were selected to examine the effects of the structural feature on the bioavailability of flavonoids using hexose transporters SGLT1 and GLUT2 in a Caco-2 BBe1 cell model. Cellular uptake and transport of all glycosides were significantly different. The glycosides also significantly inhibited cellular uptake of d-glucose, indicating the involvement of the two hexose transporters SGLT1 and GLUT2 in the absorption, and the potential of the glycosides in lowering the blood glucose level. The in silico prediction model also supported these observations. The absorption of glycosides, especially diglycosides but not the aglycones, was significantly blocked by SGLT1 and GLUT2 inhibitors (phloridzin and phloretin) and further validated in SGLT1 knockdown Caco-2 BBe1 cells.

Present status and future perspectives of breeding for buckwheat quality

Buckwheat is an important crop globally. It has been processed into cereal grain, noodles, confectionery, bread, and fermented foods for many years. Buckwheat production and processing has supported local economies and is deeply related to the culture of some regions. Buckwheat has many unique traits as a food, with a good flavor and color. In addition, buckwheat is also a healthy food because it contains bioactive compounds that have anti-oxidative, anti-hypertensive, and anti-obesity properties. Therefore, breeding of buckwheat for quality is an important issue to be addressed. Compared to other crops, there is still a lack of basic information on quality, including bioactive compounds generation and enhancement. However, some mechanisms for modifying and improving the quality of buckwheat varieties have recently been identified. Further, some varieties with improved quality have recently been developed. In this review, we summarize the issues around buckwheat quality and review the present status and future potential of buckwheat breeding for quality.

Dietary Supplementation of Black Rice Anthocyanin Extract Regulates Cholesterol Metabolism and Improves Gut Microbiota Dysbiosis in C57BL/6J Mice Fed a High-Fat and Cholesterol Diet

SCOPE

This study explores the beneficial effects of dietary supplementation of black rice anthocyanin extract (BRAE) on cholesterol metabolism and gut dysbiosis.

METHODS AND RESULTS

C57BL/6J mice are grouped into the normal chow diet group (NCD), the high-fat and the cholesterol diet group (HCD), and three treatment groups feeding HCD supplemented with various dosage of BRAE for 12 weeks. Results reveal that BRAE alleviates the increased body weight, serum triglyceride (TG), total cholesterol (TC), non-high-density lipoprotein cholesterol levels (non-HDL-C), and increased fecal sterols excretion and caecal short-chain fatty acids (SCFAs) concentration in HCD-induced hypercholesterolemic mice. Moreover, BRAE decreases hepatic TC content through the fundamental regulation of body energy balance gene, adenosine 5'-monophosphate activated protein kinase α (AMPKα). Meanwhile, BRAE improves the genes expression involved in cholesterol uptake and efflux, and preserves CYP7A1, ATP-binding cassette subfamily G member 5/8 mRNA expression, and the relative abundance of gut microbiota. Additionally, the antibiotic treatment experiment indicates that the beneficial effects of BRAE in reducing hypocholesterolemia risk largely depends on the gut microbiota homeostasis.

CONCLUSION

BRAE supplement could be a beneficial treatment option for preventing HCD-induced hypocholesterolemia and related metabolic syndromes.

Blueberry Juice Antioxidants Protect Osteogenic Activity against Oxidative Stress and Improve Long-Term Activation of the Mineralization Process in Human Osteoblast-Like SaOS-2 Cells: Involvement of SIRT1

Diets rich in fruits and vegetables with many antioxidants can be very important in the prevention and treatment of osteoporosis. Studies show that oxidative stress, often due to lack of antioxidants, is involved in alteration of bone remodeling and reduction in bone density. This study demonstrates in human osteoblast-like SaOS-2 cells that blueberry juice (BJ), containing 7.5 or 15 μg∙mL^-1 total soluble polyphenols (TSP), is able to prevent the inhibition of osteogenic differentiation and the mineralization process due to oxidative stress induced by glutathione depletion. This situation mimics a metabolic condition of oxidative stress that may occur during estrogen deficiency. The effect of BJ phytochemicals occurs through redox- and non-redox-regulated mechanisms. BJ protects from oxidative damage factors related to bone remodeling and bone formation, such as alkaline phosphatase and Runt-related transcription factor 2. It upregulates these factors by activation of sirtuin type 1 deacetylase expression, a possible molecular target for anti-osteoporotic drugs. Quantitative analysis of TSP in BJ shows high levels of anthocyanins with high antioxidant capacity and bioavailability. These novel data may be important to elucidate the molecular and cellular beneficial effects of blueberry polyphenols on bone regeneration, and they suggest their use as a dietary supplement for osteoporosis prevention and therapies.

Therapeutic Effects of Anthocyanins for Vision and Eye Health

Anthocyanin (AC) is widely used as supplement of eye health in Europe and in East Asia. In this review, I describe AC effects to clarify the mechanism is important in order to understand the effects of AC on vision health. The bioavailability of AC is quite low but, reported as intact form and many kinds of metabolite. And AC passes through the blood-aqueous fluid barrier and blood-retinal barrier. In vitro study, AC had a relaxing effect on ciliary muscle which is important to treat both myopia and glaucoma. And AC stimulate the regeneration of rhodopsin in frog rod outer segment. Furthermore, AC could inhibit the axial length and ocular length elongation in a negative lens-induced chick myopia model. In addition, we summarized clinical studies of AC intake improved dark adaptation and transient myopic shift and the improvement on retinal blood circulation in normal tension glaucoma patients.

Absorption of Anthocyanin Rutinosides after Consumption of a Blackcurrant ( Ribes nigrum L.) Extract

The dominant anthocyanins in blackcurrant are delphinidin-3-O-rutinoside and cyanidin-3-O-rutinoside. Data on their absorption and distribution in the human body are limited. Therefore, we performed a human pilot study on five healthy male volunteers consuming a blackcurrant ( Ribes nigrum L.) extract. The rutinosides and their degradation products gallic acid and protocatechuic acid were determined in plasma and urine. The rutinosides' concentrations peaked in both plasma and urine samples within 2 h of extract ingestion. The recoveries of delphinidin-3-O-rutinoside and cyanidin-3-O-rutinoside from urine samples were 0.040 ± 0.011% and 0.048 ± 0.016%, respectively, over a 48 h period. Protocatechuic acid concentration increased significantly after ingestion of the blackcurrant extract. Our results show that after ingestion of a blackcurrant extract containing delphinidin-3-O-rutinoside and cyanidin-3-O-rutinoside, significant quantities of biologically active compounds circulated in the plasma and were excreted via urine. Furthermore, these results contribute to the understanding of anthocyanin metabolism in humans.

The Anti-inflammatory Effects of Dietary Anthocyanins against Ulcerative Colitis

Ulcerative colitis (UC), which is a major form of inflammatory bowel disease (IBD), is a chronic relapsing disorder of the gastrointestinal tract affecting millions of people worldwide. Alternative natural therapies, including dietary changes, are being investigated to manage or treat UC since current treatment options have serious negative side effects. There is growing evidence from animal studies and human clinical trials that diets rich in anthocyanins, which are pigments in fruits and vegetables, protect against inflammation and increased gut permeability as well as improve colon health through their ability to alter bacterial metabolism and the microbial milieu within the intestines. In this review, the structure and bioactivity of anthocyanins, the role of inflammation and gut bacterial dysbiosis in UC pathogenesis, and their regulation by the dietary anthocyanins are discussed, which suggests the feasibility of dietary strategies for UC mitigation.

Blueberry juice protects osteocytes and bone precursor cells against oxidative stress partly through SIRT1

Oxidative stress and abnormal osteocyte apoptosis are often related to dysregulation of bone turnover and chronic bone loss, and so fruit and vegetables with high antioxidant potential may play an important role in the prevention and/or management of osteoporosis. Osteocytes are the main regulators of bone remodelling. For the first time, we demonstrate here that blueberry juice (BJ), obtained from Vaccinium myrtillus, rich in polyphenols, shows antioxidant and antiosteoclastogenic properties in MLO‐Y4 osteocytes. We report that BJ prevents oxidative stress‐induced apoptosis and reverses the increase in receptor activator of nuclear factor κB ligand and sclerostin expression, crucial factors for osteoclast activation and bone resorption. BJ is also able to prevent oxidative stress‐induced cell cytotoxicity in bone marrow mesenchymal stromal cells (MSCs), which are considered to be an important tool for cell therapy in bone disorders. No significant difference in preventing these events was observed between BJ and blueberry dry extract containing equal amounts of total soluble polyphenols. We have also shown that blueberry acts as both an antioxidant and an activator of sirtuin type 1, a class III histone deacetylase involved in cell death regulation and considered a molecular target for blocking bone resorption without affecting osteoclast survival. Overall, these novel data obtained in osteocytes and MSCs may help us clarify the mechanisms by which blueberry counteracts oxidative stress‐induced damage in bone remodelling and osteogenesis at the cellular and molecular level. Our findings are consistent with the reported beneficial effects of blueberry on bone tissue reported in animal studies, which suggest that blueberry may be a useful supplement for the prevention and/or management of osteoporosis and osteogenic process.

The Impact of O-Glycosylation on Cyanidin Interaction with RBCs and HMEC-1 Cells-Structure⁻Activity Relationships

With the aim of contributing to the knowledge about their potential therapeutic activity, we determined the biological activities of cyanidin and its selected O-glycosides in relation to erythrocytes (RBCs) and human dermal vascular endothelial cells (HMEC-1). Furthermore, on the basis of changes in the physical/functional properties of the cells, the structure–activity relationships of the compounds were determined. Concerning erythrocytes, we analyzed the antioxidant activity of the compounds and their impact on the RBCs’ shape and transmembrane potential. The compounds’ cytotoxic activity, ability to modulate apoptosis, cell cycle, and intracellular ROS generation, as well as inhibitory activity against AAPH-inducted oxidative stress, were determined in relation to HMEC-1 cells. We demonstrated that biological activity of cyanidin and its O-glycosides strongly depends on the number and type of sugar substituents, and varies depending on the extracellular environment and type of cells. The compounds are practically non-cytotoxic, and do not induce apoptosis or disturb the progression of the cell cycle. Additionally, the compounds alter the shape of RBCs, but they do not affect their transmembrane potential. They effectively protect erythrocytes against free radicals and affect intracellular reactive oxygen spices (ROS) generation under physiological and AAPH-induced oxidative stress conditions. Our results suggest a potential beneficial effect of cyanidin on the cardiovascular system.

Cyanidin-3-glucoside induces mesenchymal to epithelial transition via activating Sirt1 expression in triple negative breast cancer cells

Triple-negative breast cancer (TNBC) is a heterogeneous group of breast cancer with one common feature: distinctly metastatic nature with higher rate of relapse and shorter survival compared with other subtypes of breast cancer. The epithelial to mesenchymal transition (EMT) is highly associated with cancer metastasis. Cyanidin-3-glucoside (C3G), the most abundant anthocyanin pigment enriched in fresh fruits and vegetables, showed ideal anti-oxidant property. C3G could also inhibit certain malignant behaviors of cancer cells, however, whether repression of EMT was involved in its anti-cancer especially TNBC effect remains unknown. Herein, we report that C3G decreases the migratory and invasive nature of TNBC lines MDA-MB-231 and BT-549. Mechanistically, C3G induces reversion of EMT characterized by phenotype modulation with increased epithelial marker E-ca and ZO-1, decreased mesenchymal marker Vimentin, N-ca and EMT-associated transcription factors Snail1, Snail2. NF-κB is pivotal for EMT and Sirt1 is a NF-κB inhibitor. We show that NF-κB is attenuated and Sirt1 is induced by C3G in TNBC, respectively. And later evidence demonstrates that abrogation of Sirt1 with small interfering RNA transfection abolished NF-κB inhibition and EMT reversion by C3G. Subsequently, we show that microRNA-138(miR-138) represses Sirt1 via mRNA translation inhibition and is inhibited by C3G. Moreover, miR-138 repression is involved in Sirt1 re-activation and migratory and invasive inhibition of TNBC by C3G. Taken together, we supplied more evidence to the anti-breast cancer mechanisms of C3G.

Skin anti-inflammatory activity of rose petal extract (Rosa gallica) through reduction of MAPK signaling pathway

The aim of this study was to investigate the skin anti-inflammatory activity of rose petal extract (RPE) and the mechanisms underlying this phenomenon. Recently, flowers have been considered as dietary resources owing to their biological activities, such as inhibition of nephritis and hemorrhoids. The Rosa plant exerts various biological functions, including antioxidant and anti-microbiological activities. Herein, we confirmed the skin anti-inflammatory activity of RPE upon solar UV (sUV) exposure. RPE reduced sUV-induced COX-2 expression as well as expressions of several cytokines. Activation of MKK4-JNK, MEK-ERK, and MKK3-p38 signaling pathways, which are associated with cytokine production, was also attenuated by RPE treatment. We hypothesized these RPE-induced changes are because of its antioxidant activity, because RPE displayed drastic radical scavenging and oxygen radical absorbance capacity (ORAC). Furthermore, high anthocyanins, polyphenols, and flavonoids contents were found in RPE. Hence, these results indicated the skin anti-inflammatory activity of RPE is because of antioxidant activity.

Intestinal absorption of black chokeberry cyanidin 3-glycosides is promoted by capsaicin and capsiate in a rat ligated small intestinal loop model

Recent studies have shown that aronia (black chokeberry) and haskap fruits (contain anthocyanins) have beneficial health effects in animals and humans. However, some reports have shown that anthocyanin is poorly absorbed in the small intestine. In this study, we compared the intestinal absorption of aronia and haskap anthocyanins by using rats with a ligated small intestinal loop and cannulated portal vein. Our results clearly showed that the intestinal absorption of aronia anthocyanins was significantly lower than that of haskap anthocyanins, suggesting that the intestinal absorption of anthocyanins is influenced by the glycoside type (galactoside or glucoside). In addition, we also examined the effects of capsaicin and capsiate on intestinal anthocyanin absorption. The amount of aronia anthocyanins in portal blood was much higher when they were co-administered with capsaicin or capsiate. Our study is the first to show that the intestinal absorption of aronia anthocyanins is promoted by capsaicin and capsiate.

Cyanidin-3-O-β-glucoside, a Natural Polyphenol, Exerts Proapoptotic Effects on Activated Platelets and Enhances Megakaryocytic Proplatelet Formation

This study investigated whether the anthocyanin cyanidin-3-O-β-glucoside (Cy-3-g) could affect platelet apoptosis and proplatelet formation in vitro. Thrombin-stimulated or resting human platelets and Meg-01 megakaryocytes were incubated with Cy-3-g (0, 0.5, 5, or 50 μM). We found that the percentage of the platelet mitochondrial membrane potential treated with 5 and 50 μM Cy-3-g was significantly higher than control (15.50% ± 3.24% and 29.77% ± 4.06% versus 2.76% ± 1.33%, respectively; P < 0.05). Treatment with 5 and 50 μM Cy-3-g significantly increased phosphatidylserine exposure compared with control (40.56% ± 10.53% and 76.62% ± 8.28% versus 15.43% ± 3.93%, respectively; P < 0.05). Moreover, Cy-3-g significantly increased the expression of Bax, Bak, and cytochrome c while markedly decreasing Bcl-xL and Bcl-2 expression as well as stimulating caspase-3, caspase-9, caspase-8, Bid, and gelsolin cleavage in thrombin-activated platelets in a dose-dependent manner ( P < 0.05). However, no significant differences were observed in the apoptosis of resting platelets when treated with Cy-3-g ( P > 0.05). Furthermore, Cy-3-g significantly ( P < 0.05) enhanced cell viability (50 μM versus control, 1.34 ± 0.01 versus 0.35 ± 0.02), the number of colony-forming unit-megakaryocytes (50 μM versus control, 38 ± 3 versus 8 ± 3), CD41 expression (50 μM versus control, 96.80% ± 2.55% versus 25.57% ± 2.86%), DNA ploidy (16N) (50 μM versus control, 19.73% ± 2.34% versus 4.42% ± 1.96%), and proplatelet formation (50 μM versus control, 27.5% ± 3.77% versus 7.67% ± 2.25%) in Meg-01 cells. In conclusion, Cy-3-g promotes activated platelet apoptosis and enhances megakaryocyte proliferation, differentiation, and proplatelet formation in vitro.

Delphinidin Ameliorates Hepatic Triglyceride Accumulation in Human HepG2 Cells, but Not in Diet-Induced Obese Mice

Anthocyanin consumption is linked to benefits in obesity-related metabolic alterations and non-alcoholic fatty liver disease (NAFLD), though the functional role of delphinidin (Dp) is yet to be established. Therefore, this study examined the effects of Dp on metabolic alterations associated with NAFLD, and molecular mechanisms in HepG2 cells and diet-induced obese mice. Cells incubated with palmitate to induce lipid accumulation, concomitantly treated with Dp, reduced triglyceride accumulation by ~53%, and downregulated gene expression of CPT1A, SREBF1, and FASN without modifying AMP-activated protein kinase (AMPK) levels. C57BL/6Nhsd mice were fed a standard diet (control) or a high-fat/high-carbohydrate diet (HFHC) for 16 weeks. Mice in the HFHC group were subdivided and treated with Dp (HFHC-Dp, 15 mg/kg body weight/day) or a vehicle for four weeks. Dp did not affect body weight, energy intake, hyperglycemia, insulin resistance, or histological abnormalities elicited by the HFHC diet. Furthermore, the messenger RNA (mRNA) expressions of Acaca, and Fasn in hepatic or epididymal adipose tissue, and the hepatic sirtuin 1 (SIRT1)/liver kinase B1 (LKB1)/AMPK and proliferator-activated receptor alpha (PPARα) signaling axis did not significantly change due to the HFHC diet or Dp. In summary, Dp effectively reduced triglyceride accumulation in vitro through the modulation of lipid metabolic gene expression. However, a dose of Dp administrated in mice simulating the total daily anthocyanin intake in humans had no effect on either metabolic alterations or histological abnormalities associated with HFHC diets.

The potency of commercial blackcurrant juices to induce relaxation in porcine coronary artery rings is not correlated to their antioxidant capacity but to their anthocyanin content

OBJECTIVE

Polyphenol-rich products such as fruit juices have been found to have strong antioxidant capacities and to induce potent endothelium-dependent relaxation. We evaluated whether the commercial blackcurrant juices induced endothelium-dependent relaxation of isolated coronary arteries can be related to their antioxidant capacity and/or phenolic content.

METHODS

Six different commercial blackcurrant juices were selected. Their main phenolic compounds were measured by ultra-performance liquid chromatography and antioxidant capacity was evaluated by spectrometric methods. Vascular reactivity studies with these juices were done using isolated porcine coronary arteries.

RESULTS

The six different commercial blackcurrant juices induced relaxation ranging from 21% to 100% at the concentration of 0.5% volume per volume (v/v). The relaxation induced at 0.5% v/v was not correlated to their antioxidant capacity measured by either oxygen radical antioxidant capacity or DPPH (2,2-diphenyl-1-picrylhydrazyl) assays and also not to the ascorbic acid, total polyphenols, total flavanols, and total phenolic acid contents. In contrast, the amplitude of the relaxation was correlated to the total anthocyanins content and the individual anthocyanin concentration.

CONCLUSIONS

Correlations between relaxation amplitude and total anthocyanin or individual anthocyanin contents are of interest for the development of functional blackcurrant beverages with the potential to promote vascular protection.

A theoretical physiologically based pharmacokinetic approach for modeling the fate of anthocyanins in vivo

Recent studies on the pharmacokinetics of anthocyanins (ACNs) and their metabolites have uncovered evidence for hitherto unknown physiological effects affecting the fate of these compounds in vivo. In particular, it has been shown that the stomach, in addition to the small intestine, has an important role in absorption. Most studies still use a noncompartmental or one-compartmental approach to determine the pharmacokinetic parameters of ACNs, which does not represent the anatomical and physiological conditions that a compound is subject to in the organism. Thus, the objective of this study was to review the current knowledge of the different processes involved in the metabolism of ACNs once ingested and, based on this information, propose a theoretical physiologically based, multicompartmental pharmacokinetic (PBMK) model to describe their fate in vivo. This is the first study that reports a PBMK model for ACNs; the model provides a more physiologically representative approach for ANC metabolism, which could be used as a basis for experimental designs and interspecies scale-up.