Experimental and Theoretical Data on the Mechanism by Which Red Wine Anthocyanins Are Transported through a Human MKN-28 Gastric Cell Model

Cyanidin and Cyanidin-3-Glucoside Alleviate Peptic Ulcer Disease: Insights from in vitro, and in vivo Studies

Peptic ulcer disease (PUD) remains a significant global health issue, affecting millions despite a decrease in overall prevalence. However, complications continue to persist, with substantial mortality rates in regions like India and China. Current treatments, though effective, have limitations, driving interest in plant-derived therapy. Anthocyanins, including cyanidin and cyanidin-3-glucoside (C3G), are known for their antioxidant and anti-inflammatory properties. This study aims to explore the potential of cyanidin and C3G in alleviating PUD, focusing on their mechanisms of action and therapeutic efficacy in preclinical studies. Articles were searched in Scopus and PubMed databases and filtered for publication from 2014 to 2024, resulting in 89 articles from Scopus and 11 articles from PubMed. The articles were further screened by title, abstract, and full text, resulting in 6 articles. Cyanidin and C3G were described to be able to alleviate PUD by inhibiting the cytokine pro-inflammatory, reducing inflammation in gastric mucosa, and reducing lipid peroxidation in the gastric mucosa. These compounds have proven effective in managing other health problems, including peptic ulcers, but more in-depth exploration in clinical settings is required to confirm therapeutic potential in humans. It is necessary to validate the therapeutic efficacy and safety in human populations. This review provides an overview of preclinical studies of cyanidin and C3G, such as in vitro and in vivo, focusing on mechanism of action or their effectiveness in alleviating peptic ulcers.

Recent advances on cyanidin-3-O-glucoside in preventing obesity-related metabolic disorders: A comprehensive review

Anthocyanins, found in various pigmented plants as secondary metabolites, represent a class of dietary polyphenols known for their bioactive properties, demonstrating health-promoting effects against several chronic diseases. Among these, cyanidin-3-O-glucoside (C3G) is one of the most prevalent types of anthocyanins. Upon consumption, C3G undergoes phases I and II metabolism by oral epithelial cells, absorption in the gastric epithelium, and gut transformation (phase II & microbial metabolism), with limited amounts reaching the bloodstream. Obesity, characterized by excessive body fat accumulation, is a global health concern associated with heightened risks of disability, illness, and mortality. This comprehensive review delves into the biodegradation and absorption dynamics of C3G within the gastrointestinal tract. It meticulously examines the latest research findings, drawn from in vitro and in vivo models, presenting evidence underlining C3G's bioactivity. Notably, C3G has demonstrated significant efficacy in combating obesity, by regulating lipid metabolism, specifically decreasing lipid synthesis, increasing fatty acid oxidation, and reducing lipid accumulation. Additionally, C3G enhances energy homeostasis by boosting energy expenditure, promoting the activity of brown adipose tissue, and stimulating mitochondrial biogenesis. Furthermore, C3G shows potential in managing various prevalent obesity-related conditions. These include cardiovascular diseases (CVD) and hypertension through the suppression of reactive oxygen species (ROS) production, enhancement of endogenous antioxidant enzyme levels, and inhibition of the nuclear factor-kappa B (NF-κB) signaling pathway and by exercising its cardioprotective and vascular effects by decreasing pulmonary artery thickness and systolic pressure which enhances vascular relaxation and angiogenesis. Type 2 diabetes mellitus (T2DM) and insulin resistance (IR) are also managed by reducing gluconeogenesis via AMPK pathway activation, promoting autophagy, protecting pancreatic β-cells from oxidative stress and enhancing glucose-stimulated insulin secretion. Additionally, C3G improves insulin sensitivity by upregulating GLUT-1 and GLUT-4 expression and regulating the PI3K/Akt pathway. C3G exhibits anti-inflammatory properties by inhibiting the NF-κB pathway, reducing pro-inflammatory cytokines, and shifting macrophage polarization from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype. C3G demonstrates antioxidative effects by enhancing the expression of antioxidant enzymes, reducing ROS production, and activating the Nrf2/AMPK signaling pathway. Moreover, these mechanisms also contribute to attenuating inflammatory bowel disease and regulating gut microbiota by decreasing Firmicutes and increasing Bacteroidetes abundance, restoring colon length, and reducing levels of inflammatory cytokines. The therapeutic potential of C3G extends beyond metabolic disorders; it has also been found effective in managing specific cancer types and neurodegenerative disorders. The findings of this research can provide an important reference for future investigations that seek to improve human health through the use of naturally occurring bioactive compounds.

Anthocyanins-gut microbiota-health axis: A review

Anthocyanins are a subclass of flavonoids responsible for color in some fruits and vegetables with potent antioxidative capacity. During digestion, a larger proportion of dietary anthocyanins remains unabsorbed and reach the large intestine where they interact with the gut microbiota. Anthocyanins can modulate gut microbial populations to improve diversity and the proportion of beneficial populations, leading to alterations in short chain fatty acid and bile acid production. Some anthocyanins can be degraded into colonic metabolites, such as phenolic acids, which accumulate in the body and regulate a range of biological activities. Here we provide an overview of the effects of dietary anthocyanin consumption on gut microbial interactions, metabolism, and composition. Progression of chronic diseases has been strongly associated with imbalances in gut microbial populations. We therefore focus on the role of the gut microbiota as the 'mediator' that facilitates the therapeutic potential of anthocyanins against various chronic diseases, including obesity, type II diabetes, cardiovascular disease, neurodegenerative disease, inflammatory bowel disease, cancer, fatty liver disease, chronic kidney disease and osteoarthritis.

Unlocking the health potential of anthocyanins: a structural insight into their varied biological effects

Anthocyanins have become increasingly important to the food industry due to their colorant features and many health-promoting activities. Numerous studies have linked anthocyanins to antioxidant, anti-inflammatory, anticarcinogenic properties, as well as protection against heart disease, certain types of cancer, and a reduced risk of diabetes and cognitive disorders. Anthocyanins from various foods may exhibit distinct biological and health-promoting activities owing to their structural diversity. In this review, we have collected and tabulated the key information from various recent published studies focusing on investigating the chemical structure effect of anthocyanins on their stability, antioxidant activities, in vivo fate, and changes in the gut microbiome. This information should be valuable in comprehending the connection between the molecular structure and biological function of anthocyanins, with the potential to enhance their application as both colorants and functional compounds in the food industry.

Advances in the Preparation, Stability, Metabolism, and Physiological Roles of Anthocyanins: A Review

Anthocyanins are natural flavonoid polyphenolic compounds widely found in fruits and vegetables. They exhibit antioxidant properties and prophylactic effects in the immune and cardiovascular systems, confer protection against cancer, and contribute to the prevention of cardiovascular diseases. Thus, their incorporation into functional foods, pharmaceuticals, supplements, and cosmetic formulations aims at promoting human well-being. This review comprehensively outlined the structural attributes of anthocyanins, expanding upon diverse methodologies employed for their extraction and production. Additionally, the stability, metabolic pathways, and manifold physiological functions of anthocyanins were discussed. However, their constrained fat solubility, susceptibility to instability, and restricted bioavailability collectively curtail their applicability and therapeutic efficacy. Consequently, a multidimensional approach was imperative, necessitating the exploration of innovative pathways to surmount these limitations, thereby amplifying the utilitarian significance of anthocyanins and furnishing pivotal support for their continual advancement and broader application.

Anthocyanins: Metabolic Digestion, Bioavailability, Therapeutic Effects, Current Pharmaceutical/Industrial Use, and Innovation Potential

In this work, various concepts and features of anthocyanins have been comprehensively reviewed, taking the benefits of the scientific publications released mainly within the last five years. Within the paper, common topics such as anthocyanin chemistry and occurrence, including the biosynthesis of anthocyanins emphasizing the anthocyanin formation pathway, anthocyanin chemistry, and factors influencing the anthocyanins' stability, are covered in detail. By evaluating the recent in vitro and human experimental studies on the absorption and bioavailability of anthocyanins present in typical food and beverages, this review elucidates the significant variations in biokinetic parameters based on the model, anthocyanin source, and dose, allowing us to make basic assumptions about their bioavailability. Additionally, special attention is paid to other topics, such as the therapeutic effects of anthocyanins. Reviewing the recent in vitro, in vivo, and epidemiological studies on the therapeutic potential of anthocyanins against various diseases permits a demonstration of the promising efficacy of different anthocyanin sources at various levels, including the neuroprotective, cardioprotective, antidiabetic, antiobesity, and anticancer effects. Additionally, the studies on using plant-based anthocyanins as coloring food mediums are extensively investigated in this paper, revealing the successful use of anthocyanins in coloring various products, such as dietary and bakery products, mixes, juices, candies, beverages, ice cream, and jams. Lastly, the successful application of anthocyanins as prebiotic ingredients, the innovation potential of anthocyanins in industry, and sustainable sources of anthocyanins, including a quantitative research literature and database analysis, is performed.

Behind the Scenes of Anthocyanins-From the Health Benefits to Potential Applications in Food, Pharmaceutical and Cosmetic Fields

Anthocyanins are widespread and biologically active water-soluble phenolic pigments responsible for a wide range of vivid colours, from red (acidic conditions) to purplish blue (basic conditions), present in fruits, vegetables, and coloured grains. The pigments' stability and colours are influenced mainly by pH but also by structure, temperature, and light. The colour-stabilizing mechanisms of plants are determined by inter- and intramolecular co-pigmentation and metal complexation, driven by van der Waals, π-π stacking, hydrogen bonding, and metal-ligand interactions. This group of flavonoids is well-known to have potent anti-inflammatory and antioxidant effects, which explains the biological effects associated with them. Therefore, this review provides an overview of the role of anthocyanins as natural colorants, showing they are less harmful than conventional colorants, with several technological potential applications in different industrial fields, namely in the textile and food industries, as well as in the development of photosensitizers for dye-sensitized solar cells, as new photosensitizers in photodynamic therapy, pharmaceuticals, and in the cosmetic industry, mainly on the formulation of skin care formulations, sunscreen filters, nail colorants, skin & hair cleansing products, amongst others. In addition, we will unveil some of the latest studies about the health benefits of anthocyanins, mainly focusing on the protection against the most prevalent human diseases mediated by oxidative stress, namely cardiovascular and neurodegenerative diseases, cancer, and diabetes. The contribution of anthocyanins to visual health is also very relevant and will be briefly explored.

Anti-aging effects and mechanisms of anthocyanins and their intestinal microflora metabolites

Aging, a natural and inevitable physiological process, is the primary risk factor for all age-related diseases; it severely threatens the health of individuals and places a heavy burden on the public health-care system. Thus, strategies to extend the lifespan and prevent and treat age-related diseases have been gaining increasing scientific interest. Anthocyanins (ACNs) are a subclass of flavonoids widely distributed in fruits and vegetables. Growing evidence suggests that ACNs delay aging and relieve age-related diseases. However, owing to the low bioavailability of ACNs, their gut metabolites have been proposed to play a critical role in mediating health benefits. In this review, we introduce the biological fate of ACNs after consumption and highlight ACNs metabolites (phenolic acids) from intestinal microorganisms. Additionally, ACNs and gut metabolites exhibit outstanding anti-aging ability in Caenorhabditis elegans, Drosophila melanogaster, and mouse models, probably associated with increasing antioxidation, anti-inflammation, protein homeostasis, antiglycation, mitochondrial function, and inhibition of insulin/IGF-1 signaling (IIS). ACNs and gut metabolites have great application prospects as functional foods and drugs to delay aging and manage age-related diseases. Further investigation should focus on the interaction between ACNs and gut microbiota, including clarifying the complex metabolic pathway and maximizing the health effects of ACNs.

Contribution of the diverse experimental models to unravelling the biological scope of dietary (poly)phenols

The health benefits associated with (poly)phenols need to be supported by robust and insightful information on their biological effects. The use of in vitro, ex vivo, and in vivo models is crucial to demonstrate functionalities in specific targets. In this regard, bioaccessibility, bioavailability, and tissue/organ distribution need to be fully understood and established. In addition, the structure-function relationships, concerning both descriptive and mechanistic information, between specific compounds and therapeutic objectives, need to be supported by results obtained from in vivo studies. Nevertheless, these studies are not always possible or have some limitations, particularly concerning the mechanistic information explaining the health benefits provided that should be covered with complementary experimental models. Based on these premises, this review aims to overview the contribution of the separate experimental approaches to gain insights into the bioaccessibility, bioavailability, and bioactivity of (poly)phenols. To achieve this objective, recent evidence available on the linkage of healthy/functional foods with the incidence of non-communicable pathologies is presented. The different experimental approaches provide complementary information that allows advances to be applied to the knowledge gained on the functional properties and mechanistic facts responsible for the health attributions of polyphenols. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Stability and Antiproliferative Activity of Malvidin-Based Non-Oxonium Derivative (Oxovitisin A) Compared with Precursor Anthocyanins and Pyranoanthocyanins

Oxovitisins are a unique group of anthocyanin derivatives with a non-oxonium nature and α-pyranone (lactone) D ring on the structure. In this study, oxovitisin A was synthesized through the micro-oxidative reaction of carboxypyranomalvidin-3-O-glucoside (vitisin A) with water, and its thermostability, pH, and SO₂ color stability were studied compared with its two precursors, malvidin-3-O-glucoside (Mv3glc) and vitisin A, as well as methylpyrano-malvidin-3-O-glucoside (Me-py). Results showed that oxovitisin A exhibited the highest stabilities, which were inseparably related to its noncharged structure and the additional carbonyl group on the D ring. Moreover, the antiproliferative capacity of oxovitisin A was comparatively evaluated against two human gastrointestinal cancer cell lines. Interestingly, oxovitisin A presented the strongest antiproliferative ability on MKN-28 (IC₅₀ = 538.42 ± 50.06 μM) and Caco-2 cells (IC₅₀ = 434.85 ± 11.87 μM) compared with two other pyranoanthocyanins. Therefore, we conclude that oxovitisin A as a highly stable anthocyanin derivative still exhibits a satisfactory antiproliferative ability.

Nanoencapsulated anthocyanin as a functional ingredient: Technological application and future perspectives

Anthocyanins are an important group of phenolic compounds responsible for pigmentation in several plants, and regular consumption is associated with a reduced risk of several diseases. However, the application of anthocyanins in foods represents a challenge due to molecular instability. The encapsulation of anthocyanins in nanostructures is a viable way to protect from the factors responsible for degradation and enable the industrial application of these compounds. Nanoencapsulation is a set of techniques in which the bioactive molecules are covered by resistant biomaterials that protect them from chemical and biological factors during processing and storage. This review comprehensively summarizes the existing knowledge about the structure of anthocyanins and molecular stability, with a critical analysis of anthocyanins' nanoencapsulation, the main encapsulating materials (polysaccharides, proteins, and lipids), and techniques used in the formation of nanocarriers to protect anthocyanins. Some studies point to the effectiveness of nanostructures in maintaining anthocyanin stability and antioxidant activity. The main advantages of the application of nanoencapsulated anthocyanins in foods are the increase in the nutritional value of the food, the addition of color, the increase in food storage, and the possible increase in bioavailability after oral ingestion. Nanoencapsulation improves stability for anthocyanin, thus demonstrating the potential to be included in foods or used as dietary supplements, and current limitations, challenges, and future directions of anthocyanins' have also been discussed.

Dietary polyglycosylated anthocyanins, the smart option? A comprehensive review on their health benefits and technological applications

Over the years, anthocyanins have emerged as one of the most enthralling groups of natural phenolic compounds and more than 700 distinct structures have already been identified, illustrating the exceptional variety spread in nature. The interest raised around anthocyanins goes way beyond their visually appealing colors and their acknowledged structural and biological properties have fueled intensive research toward their application in different contexts. However, the high susceptibility of monoglycosylated anthocyanins to degradation under certain external conditions might compromise their application. In that regard, polyglycosylated anthocyanins (PGA) might offer an alternative to overcome this issue, owing to their peculiar structure and consequent less predisposition to degradation. The most recent scientific and technological findings concerning PGA and their food sources are thoroughly described and discussed in this comprehensive review. Different issues, including their physical-chemical characteristics, consumption, bioavailability, and biological relevance in the context of different pathologies, are covered in detail, along with the most relevant prospective technological applications. Due to their complex structure and acyl groups, most of the PGA exhibit an overall higher stability than the monoglycosylated ones. Their versatility allows them to act in a wide range of pathologies, either by acting directly in molecular pathways or by modulating the disease environment attributing an added value to their food sources. Their recent usage for technological applications has also been particularly successful in different industry fields including food and smart packaging or in solar energy production systems. Altogether, this review aims to put into perspective the current state and future research on PGA and their food sources.

Inhibitory effect of polyphenols (phenolic acids, lignans, and stilbenes) on cancer by regulating signal transduction pathways: a review

Natural products, especially polyphenols (phenolic acids, lignans, and stilbenes) are suggested to be more potent anticancer drugs because of their no or less adverse effects, excess availability, high accuracy, and secure mode of action. In the present review, potential anticancer mechanisms of action of some polyphenols including phenolic acids, lignans, and stilbenes are discussed based on clinical, epidemiological, in vivo, and in vitro studies. The emerging evidence revealed that phenolic acids, lignans, and stilbenes induced apoptosis in the treatment of breast (MCF-7), colon (Caco-2), lung (SKLU-1), prostate (DU-145 and LNCaP), hepatocellular (hepG-2), and cervical (A-431) cancer cells, cell cycle arrest (S/G2/M/G1-phases) in gastric (MKN-45 and MKN-74), colorectal (HCT-116), bladder (T-24 and 5637), oral (H-400), leukemic (HL-60 and MOLT-4) and colon (Caco-2) cancer cells, and inhibit cell proliferation against the prostate (PC-3), liver (LI-90), breast (T47D and MDA-MB-231), colon (HT-29 and Caco-2), cervical (HTB-35), and MIC-1 cancer cells through caspase-3, MAPK, AMPK, Akt, NF-κB, Wnt, CD95, and SIRT1 pathways. Based on accumulated data, we suggested that polyphenols could be considered as a viable therapeutic option in the treatment of cancer cells in the near future.

Current knowledge of anthocyanin metabolism in the digestive tract: absorption, distribution, degradation, and interconversion

Potential roles for anthocyanins in preventing various chronic diseases have been reported. These compounds are highly sensitive to external conditions and are susceptible to degradation, which increases the complexity of their metabolism in vivo. This review discusses anthocyanin metabolism in the digestive tract, phase I and II metabolism, and enterohepatic circulation (EHC), as well as their distribution of anthocyanins in blood, urine, and several organs. In the oral cavity, anthocyanins are partly hydrolyzed by microbiota into aglycones which are then conjugated by glucuronidase. In stomach, anthocyanins are absorbed without deglycosylation via specific transporters, such as sodium-dependent glucose co-transporter 1 and facilitative glucose transporters 1, while in small intestine, they are mainly absorbed as aglycones. High polymeric anthocyanins are easily degraded into low-polymeric forms or smaller phenolic acids by colonic microbiota, which improves their absorption. Anthocyanins and their derivatives are modified by phase I and II metabolic enzymes in cells and are released into the blood via the gastrovascular cavity into EHC. Notably, interconversion can be occurred under the action of enzymes such as catechol-O-methyltransferase. Taking together, differences in anthocyanin absorption, distribution, metabolism, and excretion largely depend on their glycoside and aglycone structures.

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.

A Review of the Properties of Anthocyanins and Their Influence on Factors Affecting Cardiometabolic and Cognitive Health

The incidence of cardiovascular and metabolic diseases has increased over the last decades and is an important cause of death worldwide. An upcoming ingredient on the nutraceutical market are anthocyanins, a flavonoid subgroup, abundant mostly in berries and fruits. Epidemiological studies have suggested an association between anthocyanin intake and improved cardiovascular risk, type 2 diabetes and myocardial infarct. Clinical studies using anthocyanins have shown a significant decrease in inflammation markers and oxidative stress, a beneficial effect on vascular function and hyperlipidemia by decreasing low-density lipoprotein and increasing high-density lipoprotein. They have also shown a potential effect on glucose homeostasis and cognitive decline. This review summarizes the effects of anthocyanins in in-vitro, animal and human studies to give an overview of their application in medical prevention or as a dietary supplement.

Grain Dimension, Nutrition and Nutraceutical Properties of Black and Red Varieties of Rice in India

Traditional colored rice varieties in India are the source of carbohydrates, phytochemicals and minerals. They facilitate the growth of probiotics in intestine and protect human from many chronic diseases. The present study investigated the nutritional properties such as total sugars, digestible sugars, resistant sugars, hydrolysis index, glycemic index and total proteins of thirteen colored varieties of rice in India. Nutraceutical properties like anti diabetic and prebiotic activity were investigated by standard methods. Chak hao poreiton and mappillai samba grains were 6.3 mm in length. Lowest length of 5.1 mm was recorded in 60 m Kuruvai. Among the rice varieties, mappillai samba has high concentration of digestible starch of 91% and Chak hao poreiton had low concentration of 62%. Resistant starch was 38% in Chak hao poreiton and 8% in mappillai samba. Lowest glycemic index of 52 and 53 were recorded in karuthakar poha and Chak hao poreiton respectively. Anthocyanin extracted from Chak hao poreiton inhibited 24% of human pancreatic α-amylase activity. It significantly increased the probiotic number from 0.15 CFU/mL to 1.95 CFU/mL. The study revealed that the black rice variety, Chak hao poreiton was rich in resistant starch and exhibited low glycemic index. The anthocyanins from Chak hao poreiton possessed significant antidiabetic and prebiotic activity. Molecular docking studies revealed the interaction of anthocyanin with pancreatic α-amylase, β-glucosidase and GLUT1.

Anthocyanin Bioactivity in Obesity and Diabetes: The Essential Role of Glucose Transporters in the Gut and Periphery

Obesity and type-2 diabetes trends continue to worsen in the United States. Dietary anthocyanins (typically provided by berries and other fruits) are reported to have protective effects against both conditions using a variety of experimental research models including animal and human feeding studies. This review highlights studies that explore the biochemical pathways in both tissue and rodent models which could explain clinical improvements noted with anthocyanin consumption. First, the primary mode of intestinal absorption of anthocyanins is through both sGLT1 and GLUT2 glucose transporters. Stronger binding affinities may allow anthocyanins to be more inhibitive to glucose absorption compared to the reverse, where GLUT2 expression may also be affected. Genetic or chemical inhibition of sGLT1 or GLUT2 demonstrate their essential function in anthocyanin absorption across the enterocyte, where the former interacts with a greater variety of anthocyanins but the latter is the major transporter for specific anthocyanin-glycosides. Once absorbed, anthocyanins positively modulate GLUT4 density and function in both skeletal muscle and adipose tissues via the upregulation of AMPK and restoration of insulin sensitivity. Antioxidant properties and phosphodiesterase inhibition by anthocyanins promote both mitochondrial function and density which could be novel targets for dietary management of obesity and its complications.

Exploring the Applications of the Photoprotective Properties of Anthocyanins in Biological Systems

Due to their physical and chemical characteristics, anthocyanins are amongst the most versatile groups of natural compounds. Such unique signature makes these compounds a focus in several different areas of research. Anthocyanins have well been reported as bioactive compounds in a myriad of health disorders such as cardiovascular diseases, cancer, and obesity, among others, due to their anti-inflammatory, antioxidant, anti-diabetic, anti-bacterial, and anti-proliferative capacities. Such a vast number of action mechanisms may be also due to the number of structurally different anthocyanins plus their related derivatives. In this review, we highlight the recent advances on the potential use of anthocyanins in biological systems with particular focus on their photoprotective properties. Topics such as skin aging and eye degenerative diseases, highly influenced by light, and the action of anthocyanins against such damages will be discussed. Photodynamic Therapy and the potential role of anthocyanins as novel photosensitizers will be also a central theme of this review.

Brás N, Mateus N, de Freitas V, Fernandes I. Anthocyanins as Antidiabetic Agents-In Vitro and In Silico Approaches of Preventive and Therapeutic Effects

Many efforts have been made in the past two decades into the search for novel natural and less-toxic anti-diabetic agents. Some clinical trials have assigned this ability to anthocyanins, although different factors like the food source, the amount ingested, the matrix effect and the time of consumption (before or after a meal) seem to result in contradictory conclusions. The possible mechanisms involved in these preventive or therapeutic effects will be discussed-giving emphasis to the latest in vitro and in silico approaches. Therapeutic strategies to counteract metabolic alterations related to hyperglycemia and Type 2 Diabetes Mellitus (T2DM) may include: (a) Inhibition of carbohydrate-metabolizing enzymes; (b) reduction of glucose transporters expression or activity; (c) inhibition of glycogenolysis and (d) modulation of gut microbiota by anthocyanin breakdown products. These strategies may be achieved through administration of individual anthocyanins or by functional foods containing complexes of anthocyanin:carbohydrate:protein.

Interactions of dietary polyphenols with epithelial lipids: advances from membrane and cell models in the study of polyphenol absorption, transport and delivery to the epithelium

Currently, diet-related diseases such as diabetes, obesity, hypertension, and cardiovascular diseases account for 70% of all global deaths. To counteract the rising prevalence of non-communicable diseases governments are investing in persuasive educational campaigns toward the ingestion of fresh fruits and vegetables. The intake of dietary polyphenols abundant in Mediterranean and Nordic-type diets holds great potential as nutritional strategies in the management of diet-related diseases. However, the successful implementation of healthy nutritional strategies relies on a pleasant sensory perception in the mouth able to persuade consumers to adopt polyphenol-rich diets and on a deeper understanding on the chemical modifications, that affect not only their chemical properties but also their physical interaction with epithelial lipids and in turn their permeability, location within the lipid bilayer, toxicity and biological activity, and fate during absorption at the gastro-intestinal epithelium, transport in circulation and delivery to the endothelium. In this paper, we review the current knowledge on the interactions between polyphenols and their metabolites with membrane lipids in artificial membranes and epithelial cell models (oral, stomach, gut and endothelium) and the findings from polyphenol-lipid interactions to physiological processes such as oral taste perception, gastrointestinal absorption and endothelial health. Finally, we discuss the limitations and challenges associated with the current experimental approaches in membrane and cell model studies and the potential of polyphenol-rich diets in the quest for personalized nutritional strategies ("personalized nutrition") to assist in the prevention, treatment, and management of non-communicable diseases in an increasingly aged population.

Recent advances in extracting phenolic compounds from food and their use in disease prevention and as cosmetics

Phenolic compounds in plants are essential components of human nutrition, which provide various health benefits. However, some missing links became the research in phenolic compounds structures and potential applications in a challenging work. Despite universal extraction methods with mixtures of different organic solvents are generally adopted in the analysis of phenolic compounds, a need for establish a specific procedure is still open. The great heterogeneity in food and food by-products matrices and the lack of standardized methods which combine chromatographic with spectrophotometric techniques to calculate the amount of phenolic compounds joined with the absence of specific standards hamper to accurate know the real amount of phenolic compounds. Indeed, the high complexity in nature and chemistry of phenolic compounds clearly difficult to establish a daily intake to obtain certain healthy outcomes. Hence, despite the potential of phenolic compounds to use them in cosmetic and healthy applications have been widely analyzed, some concerns must be considered. The chemical complexity, the interactions between phenolic compounds and other food components and the structural changes induced by food processing joined with the lack in the understanding of phenolic compounds metabolism and bioavailability undergo the need to conduct a comprehensive review of each factors influencing the final activity of phenolic compounds. This paper summarizes the potential of phenolic compounds for disease prevention and cosmetics production, as well as their many other uses derived from their antioxidant activity. This paper illustrates the potential of phenolic compounds for disease prevention and cosmetics production, as well as their many other uses derived from their antioxidant activity.

Wine, food, and health

Wine has historically been associated with religious rights, used as a salubrious beverage, employed as a medication as well as a medicinal solvent, and consumed as a food accompaniment. It is the last use that is most intimately associated in the minds of most modern consumers. Despite this, there is little flavor commonality on which pairing could be based. The first section of the chapter examines this feature and wine's primary role as a palate cleanser and food condiment. The synergistic role of food and wine in suppressing each other's least pleasant attributes is also explained. The final section deals with the latest evidence relating to the many beneficial health effects of moderate wine consumption, shortfalls in the data, headache induction, dental erosion, and conditions under which wine intake is contraindicated.

The NCI-N87 Cell Line as a Gastric Epithelial Model to Study Cellular Uptake, Trans-Epithelial Transport, and Gastric Anti-Inflammatory Properties of Anthocyanins

Anthocyanins are ubiquitous plant pigments with reported antioxidant, anti-inflammatory, and anti-cancer activities. To better understand these benefits, metabolism of anthocyanins requires further evaluation, especially in the stomach. Mammalian cell cultures provide useful models for investigating compound metabolism and absorption, but they are generally maintained at physiological pH. The NCI-N87 cell line is an acid-stable model of the gastric epithelium used to study gastric drug metabolism. The objective of this work was to investigate the uptake, trans-epithelial transport, and anti-inflammatory activity of anthocyanins by the NCI-N87 cell line. The cells formed a coherent monolayer, stable ≤32 days post confluency. Minimal effects on monolayer integrity were observed when the pH of the apical chamber was adjusted to pH 3.0, 5.0, or 7.4. Anthocyanins were transported across the NCI-N87 cell monolayer at 37 °C, but not at 0 °C, suggesting a facilitated process. Chokeberry anthocyanins (0-1500 μM) were not cytotoxic. At apical pH 3.0, they had anti-inflammatory properties by significantly attenuating IL-8 secretion when added to medium before, during, and after incubation with IL-1β. These results suggest that the NCI-N87 cell line is a physiologically relevant model for in vitro studies of the transport, anti-inflammatory and potential anti-carcinogenic activities of anthocyanins in gastric tissue.

Purple-fleshed sweet potato acylated anthocyanins: Equilibrium network and photophysical properties

Two anthocyanins from purple-fleshed sweet potato were isolated and characterized by LC-MS and NMR analysis. They were identified as peonidin-3-(6'-hydroxybenzoyl)-sophoroside-5-glucoside and peonidin-3-(6'-hydroxybenzoyl-6″-caffeoyl)-sophoroside-5-glucoside. The acid-base dynamics of these acylated anthocyanins was evaluated by means of pH jump techniques. Equilibrium and kinetic constants were determined and, in general, these anthocyanins demonstrated a higher capacity in retaining the red and blue colors at acidic and basic pH values, suggesting a higher resistance to pH variations compared to the parent anthocyanin, peonidin-3-O-glucoside. The presence of acyl groups and additional glucoside moieties seems to determine this particular characteristic. The fluorescence properties of these anthocyanins were evaluated. Overall, the species present at higher pH values (7-9) showed higher fluorescence intensity for both anthocyanins, with an optimum λ_ex/λ_em pair at λ_ex 610 nm/λ_em 640 nm. The fluorescence characteristics of these anthocyanins were used to evaluate their location in gastric and intestinal cells by fluorescence microscopy.

Anthocyanins: From Sources and Bioavailability to Cardiovascular-Health Benefits and Molecular Mechanisms of Action

Anthocyanins are phytochemicals widely found in plant foods, with berries and fruit-derived beverages as the main dietary sources. Accumulating evidence suggests the positive role of anthocyanins in preserving cardiovascular health. Epidemiological data show an association between anthocyanin intake and lower risk of myocardial infarction and cardiovascular-disease-related mortality. Clinical studies report the beneficial effects of the consumption of different anthocyanin-rich sources on surrogate markers of cardiovascular risk. Animal and in vitro evidence suggest the protective role of anthocyanins in dysfunctions related to the development of cardiovascular diseases. Still, the underlying molecular mechanisms of anthocyanin action seem complex and are not entirely clear. This review aims to give a comprehensive update on anthocyanins and their cardioprotective properties. It provides information on their sources; quantities consumed through diet; absorption; bioavailability; cardiovascular properties; and underlying mechanisms of action, including their effects on gene and protein expression and their interactions with cell-signaling pathways and miRNAs.

GLUT1 and GLUT3 involvement in anthocyanin gastric transport- Nanobased targeted approach

Anthocyanins may protect against a myriad of human diseases. However few studies have been conducted to evaluate their bioavailability so their absorption mechanism remains unclear. This study aimed to evaluate the role of two glucose transporters (GLUT1 and GLUT3) in anthocyanins absorption in the human gastric epithelial cells (MKN-28) by using gold nanoparticles to silence these transporters. Anthocyanins were purified from purple fleshed sweet potatoes and grape skin. Silencing of GLUT1 and/or GLUT3 mRNA was performed by adding AuNP@GLUT1 and/or AuNP@GLUT3 to MKN-28 cells. Downregulation of mRNA expression occurred concomitantly with the reduction in protein expression. Malvidin-3-O-glucoside (Mv3glc) transport was reduced in the presence of either AuNP@GLUT1 and AuNP@GLUT3, and when both transporters were blocked simultaneously. Peonidin-3-(6'-hydroxybenzoyl)-sophoroside-5-glucoside (Pn3HBsoph5glc) and Peonidin-3-(6'-hydroxybenzoyl-6″-caffeoyl)-sophoroside-5-glucoside (Pn3HBCsoph5glc) were assayed to verify the effect of the sugar moiety esterification at glucose B in transporter binding. Both pigments were transported with a lower transport efficiency compared to Mv3glc, probably due to steric hindrance of the more complex structures. Interestingly, for Pn3HBCsoph5glc although the only free glucose is at C5 and the inhibitory effect of the nanoparticles was also observed, reinforcing the importance of glucose on the transport regardless of its position or substitution pattern. The results support the involvement of GLUT1 and GLUT3 in the gastric absorption of anthocyanins.

Polyphenols and bioavailability: an update

Based on many cell culture, animal and human studies, it is well known that the most challenge issue for developing polyphenolics as chemoprevention or anti-diabtetic agents is the low oral bioavailability, which may be the major reason relating to its ambiguous therapeutic effects and large inter-individual variations in clinical trials. This review intends to highlight the unscientific evaluation on the basis of the published data regarding in vitro bioactivity of polyphenols, which may sometimes mislead the researchers and to conclude that: first, bio-accessibilities values obtained in the studies for polyphenols should be highly reconsidered in accordance with the abundant newly identified circulating and excreted metabolites, with a particular attention to colonic metabolic products which are obviously contributing much more than expected to their absorptions; second, it is phenolic metabolites, which are formed in the small intestine and hepatic cells,low molecular weight catabolic products of the colonic microflora to travel around the human body in the circulatory system or reach body tissues to elicit bioactive effects. It is concluded that better performed in vivo intervention and in vitro mechanistic studies are needed to fully understand how these molecules interact with human physiological and pathological processes.

Bioengineering a novel 3D in vitro model of gastric mucosa for stomach permeability studies

The field of stomach-directed therapeutics and diagnosis is still hampered by the lack of reliable in vitro models that closely mimic the gastric mucosa where gastric cancer cells are generally confined. Here we propose a rapid, complex, and innovative 3D in vitro model of the gastric mucosa, by extending a conventional gastric monolayer model to an inner stratum of the mucosa - the lamina propria. The developed model comprises normal stomach fibroblasts embedded in a 3D RGD-modified alginate hydrogel prepared on the basolateral side of a Transwell® insert, mimicking the extracellular matrix and cellular component of the lamina propria, onto which a moderately differentiated adenocarcinoma stomach cell line (MKN74) was seeded, reproducing the physiological conditions of the gastric barrier. The integrity and functionality of the in vitro model was evaluated through permeability studies of FITC-dextran and 200 nm fluorescent polystyrene nanoparticles at gastric conditions. Nanoparticle transport was pH-dependent and strongly impacted by the biomimetic lamina propria, highlighting that a gastric extracellular matrix (ECM)-like microenvironment should be integrated in an in vitro permeability model to be adopted as a reliable evaluation tool of innovative therapeutics and diagnosis of gastric diseases. STATEMENT OF SIGNIFICANCE: Current in vitro models of the gastric mucosa are limited to simplistic 2D cell culture systems, which ignore the dimensionality of the stomach wall and make it difficult to reliably test new therapeutic approaches to gastric pathologies. By combining stomach fibroblasts embedded within a 3D RGD-modified alginate hydrogel and epithelial gastric cancer cells in a Transwell® system, we established a new biomimetic model of the stomach mucosa. Epithelial cells recreate the gastric epithelium, while the cell-laden 3D hydrogel recapitulates both the cellular composition and dimensionality of the extracellular matrix of gastric lamina propria. This cellularized 3D model stands as a promising evaluation platform to assist the development of new strategies for the treatment and diagnosis of gastric diseases.

Anthocyanins and their gut metabolites attenuate monocyte adhesion and transendothelial migration through nutrigenomic mechanisms regulating endothelial cell permeability

Cardioprotective effects of dietary anthocyanins are partly attributed to their ability to maintain endothelial function. However, the underlying cellular and molecular mechanisms of action are not fully understood. This study aimed to evaluate the effect of anthocyanins and their gut metabolites, at physiologically-relevant conditions, on endothelial cell (EC) function and decipher the underlying molecular mechanisms of action using integrated omics approaches. Primary EC were treated with a mixture of 0.1 μM cyanidin-3-arabinoside, 0.1 μM cyanidin-3-galactoside, 0.1 μM cyanidin-3-glucoside, 0.1 μM delphinidin-3-glucoside, 0.1 μM peonidin-3-glucoside and 0.5 μM 4-hydroxybenzaldehyde for 3 h or a mixture of gut metabolites: 0.2 μM protocatechuic, 2 μM vanillic, 1 μM ferulic and 2 μM hippuric acids for 18 h. Also, successive exposure of EC to both mixtures was performed to mimic anthocyanin pharmacokinetics following their intake. Inflammatory stress was induced using TNFα and monocytes added to assess adhesion and transmigration. Effects of these mixtures on gene, miRNA expression and their potential interaction with cell signalling were investigated. Anthocyanins and their gut metabolites significantly reduced monocyte adhesion and transendothelial migration. Gene expression analysis, using macroarrays, showed that tested compounds modulated the expression of genes involved in cell-cell adhesion, cytoskeleton organisation or focal adhesion. Bioinformatics analyses of gene expression data identified potential transcription factors involved in the observed nutrigenomic effects and signalling proteins regulating their activity. Molecular docking revealed cell signalling proteins to which these bioactives may bind to and potentially affect their activity and the activation of downstream signalling, effects that were in agreement with the results of Western blot analyses. Microarray analysis showed that anthocyanins and their gut metabolites affected miRNA expression in EC, especially those involved in regulation of EC permeability, contributing to the observed changes in EC function. Integration of these results revealed endothelial-protective properties of anthocyanins and their gut metabolites and deciphered new underlying multi-target and multi-layered mode of action.

Dietary Anthocyanins and Insulin Resistance: When Food Becomes a Medicine

Insulin resistance is an abnormal physiological state that occurs when insulin from pancreatic β-cells is unable to trigger a signal transduction pathway in target organs such as the liver, muscles and adipose tissues. The loss of insulin sensitivity is generally associated with persistent hyperglycemia (diabetes), hyperinsulinemia, fatty acids and/or lipid dysregulation which are often prevalent under obesity conditions. Hence, insulin sensitizers are one class of drugs currently employed to treat diabetes and associated metabolic disorders. A number of natural products that act through multiple mechanisms have also been identified to enhance insulin sensitivity in target organs. One group of such compounds that gained interest in recent years are the dietary anthocyanins. Data from their in vitro, in vivo and clinical studies are scrutinized in this communication to show their potential health benefit through ameliorating insulin resistance. Specific mechanism of action ranging from targeting specific signal transduction receptors/enzymes to the general antioxidant and anti-inflammatory mechanisms of insulin resistance are presented.

Pharmacokinetics of table and Port red wine anthocyanins: a crossover trial in healthy men

This study was designed to evaluate the pharmacokinetics of Port and table red wine anthocyanins in healthy men. Volunteers were recruited to drink 250 mL of a table red wine (221 mg of anthocyanins) and 150 mL of young Port red wine (49 mg of anthocyanins). Venous blood was collected from participants at 0, 15, 30, 60 and 120 min after wine ingestion. Urine samples were collected at baseline and at 120 min. Anthocyanins and anthocyanin metabolites in plasma and urine samples were quantified by HPLC-DAD and tentatively identified by LC-MS. Red wine anthocyanins were detected in their intact forms in both plasma and urine samples, but the glucuronylated metabolites of peonidin and malvidin (PnGlucr and MvGlucr) were the two main derivatives detected after both red wine consumptions. For the first time, and supported by the synthesis of Mv3Glucr, the main pathway followed by Mv3glc after absorption was described and involves anthocyanidin conjugation with glucuronic acid after glucose removal. Despite the lower total content of anthocyanins ingested when volunteers drank Port wine, no differences were observed in the plasma C_max of MvGlucr and PnGlucr after table and Port red wine consumption. The relative bioavailability of anthocyanins in Port wine was 96.58 ± 5.74%, compared to the anthocyanins present in red wine. In conclusion, both Port and table red wines are good sources of bioavailable anthocyanins.

Time, Concentration, and pH-Dependent Transport and Uptake of Anthocyanins in a Human Gastric Epithelial (NCI-N87) Cell Line

Anthocyanins are the largest class of water soluble plant pigments and a common part of the human diet. They may have many potential health benefits, including antioxidant, anti-inflammatory, anti-cancer, and cardioprotective activities. However, anthocyanin metabolism is not well understood. Studies suggest that anthocyanins absorption may occur in the stomach, in which the acidic pH favors anthocyanin stability. A gastric epithelial cell line (NCI-N87) has been used to study the behavior of anthocyanins at a pH range of 3.0-7.4. This work examines the effects of time (0-3 h), concentration (50-1500 µM), and pH (3.0, 5.0, 7.4) on the transport and uptake of anthocyanins using NCI-N87 cells. Anthocyanins were transported from the apical to basolateral side of NCI-N87 cells in time and dose dependent manners. Over the treatment time of 3 h the rate of transport increased, especially with higher anthocyanin concentrations. The non-linear rate of transport may suggest an active mechanism for the transport of anthocyanins across the NCI-N87 monolayer. At apical pH 3.0, higher anthocyanin transport was observed compared to pH 5.0 and 7.4. Reduced transport of anthocyanins was found to occur at apical pH 5.0.

Wine Flavonoids in Health and Disease Prevention

Wine, and particularly red wine, is a beverage with a great chemical complexity that is in continuous evolution. Chemically, wine is a hydroalcoholic solution (~78% water) that comprises a wide variety of chemical components, including aldehydes, esters, ketones, lipids, minerals, organic acids, phenolics, soluble proteins, sugars and vitamins. Flavonoids constitute a major group of polyphenolic compounds which are directly associated with the organoleptic and health-promoting properties of red wine. However, due to the insufficient epidemiological and in vivo evidences on this subject, the presence of a high number of variables such as human age, metabolism, the presence of alcohol, the complex wine chemistry, and the wide array of in vivo biological effects of these compounds suggest that only cautious conclusions may be drawn from studies focusing on the direct effect of wine and any specific health issue. Nevertheless, there are several reports on the health protective properties of wine phenolics for several diseases such as cardiovascular diseases, some cancers, obesity, neurodegenerative diseases, diabetes, allergies and osteoporosis. The different interactions that wine flavonoids may have with key biological targets are crucial for some of these health-promoting effects. The interaction between some wine flavonoids and some specific enzymes are one example. The way wine flavonoids may be absorbed and metabolized could interfere with their bioavailability and therefore in their health-promoting effect. Hence, some reports have focused on flavonoids absorption, metabolism, microbiota effect and overall on flavonoids bioavailability. This review summarizes some of these major issues which are directly related to the potential health-promoting effects of wine flavonoids. Reports related to flavonoids and health highlight some relevant scientific information. However, there is still a gap between the knowledge of wine flavonoids bioavailability and their health-promoting effects. More in vivo results as well as studies focused on flavonoid metabolites are still required. Moreover, it is also necessary to better understand how biological interactions (with microbiota and cells, enzymes or general biological systems) could interfere with flavonoid bioavailability.

Anthocyanins and Flavanones Are More Bioavailable than Previously Perceived: A Review of Recent Evidence

This review considers recent investigations on the bioavailability of anthocyanins and flavanones. Both flavonoids are significant dietary components and are considered to be poorly bioavailable, as only low levels of phase II metabolites appear in the circulatory system and are excreted in urine. However, when lower molecular weight phenolic and aromatic ring-fission catabolites, produced primarily by the action of the colonic microbiota, are taken into account, it is evident that anthocyanins and flavanones are much more bioavailable than previously envisaged. The metabolic events to which these flavonoids are subjected as they pass along the gastrointestinal tract and are absorbed into the circulatory system prior to their rapid elimination by renal excretion are highlighted. Studies on the impact of other food components and the probiotic intake on flavonoid bioavailability are summarized, as is the bioactivity of metabolites and catabolites assayed using a variety of in vitro model systems.

A Quinacrine Analogue Selective Against Gastric Cancer Cells: Insight from Biochemical and Biophysical Studies

One of the earliest synthetic antimalarial drugs, quinacrine, was recently reported as interesting for the treatment of acute myeloid leukemia. Inspired by this and similar findings, we evaluated a set of quinacrine analogues against gastric (MKN-28), colon (Caco-2), and breast (MFC-7) cancer cell lines and one normal human fibroblast cell line (HFF-1). All the compounds, previously developed by us as dual-stage antimalarial leads, displayed antiproliferative activity, and one of the set stood out as selective toward the gastric cancer cell line, MKN-28. Interestingly, this compound was transported across an in vitro MKN-28 model cell line in low amounts, and approximately 80 % was trapped inside those cells. Nuclear targeting of the same compound and its interactions with calf thymus DNA were assessed through combined fluorescence microscopy, spectroscopy, and calorimetry studies, which provided evidence for the compound's ability to reach the nucleus and to interact with DNA.

Cyanidin-3-O-glucoside: Physical-Chemistry, Foodomics and Health Effects

Anthocyanins (ACNs) are plant secondary metabolites from the flavonoid family. Red to blue fruits are major dietary sources of ACNs (up to 1 g/100 g FW), being cyanidin-3-O-glucoside (Cy3G) one of the most widely distributed. Cy3G confers a red hue to fruits, but its content in raspberries and strawberries is low. It has a good radical scavenging capacity (RSC) against superoxide but not hydroxyl radicals, and its oxidative potential is pH-dependent (58 mV/pH unit). After intake, Cy3G can be metabolized (phases I, II) by oral epithelial cells, absorbed by the gastric epithelium (1%-10%) and it is gut-transformed (phase II &amp; microbial metabolism), reaching the bloodstream (<1%) and urine (about 0.02%) in low amounts. In humans and Caco-2 cells, Cy3G's major metabolites are protocatechuic acid and phloroglucinaldehyde which are also subjected to entero-hepatic recycling, although caffeic acid and peonidin-3-glucoside seem to be strictly produced in the large bowel and renal tissues. Solid evidence supports Cy3G's bioactivity as DNA-RSC, gastro protective, anti-inflammatory, anti-thrombotic chemo-preventive and as an epigenetic factor, exerting protection against Helicobacter pylori infection, age-related diseases, type 2 diabetes, cardiovascular disease, metabolic syndrome and oral cancer. Most relevant mechanisms include RSC, epigenetic action, competitive protein-binding and enzyme inhibition. These and other novel aspects on Cy3G's physical-chemistry, foodomics, and health effects are discussed.