Cranberry Phytochemicals Research Articles

Identification of antiviral phytochemicals from cranberry as potential inhibitors of SARS-CoV-2 main protease (Mpro)

Cranberry phytochemicals are known to possess antiviral activities. In the current study, we explored the therapeutic potential of cranberry against SARS-CoV-2 by targeting its main protease (Mpro) enzyme. Firstly, phytochemicals of cranberry origin were identified from three independent databases. Subsequently, virtual screening, using molecular docking and molecular dynamics simulation approaches, led to the identification of three lead phytochemicals namely, cyanidin 3-O-galactoside, β-carotene and epicatechin. Furthermore, in vitro enzymatic assays revealed that cyanidin 3-O-galactoside had the highest inhibitory potential with IC50 of 9.98 μM compared to the other two phytochemicals. Cyanidin 3-O-galactoside belongs to the class of anthocyanins. Anthocyanins extracted from frozen cranberry also exhibited the highest inhibitory potential with IC50 of 23.58 μg/ml compared to the extracts of carotenoids and flavanols, the class for β-carotene and epicatechin, respectively. Finally, we confirm the presence of the phytochemicals in the cranberry extracts using targeted LC-MS/MS analysis. Our results, therefore, indicate that the identified cranberry-derived bioactive compounds as well as cranberry could be used for therapeutic interventions against SARS-CoV-2.

Anti-inflammatory Activities of Cranberry Fruit Extracts in Human THP-1 Monocytes are Influenced by Their Phytochemical Composition

The secondary metabolite content of cranberry fruits can vary with cultivar and environmental factors, which may in turn impact their potential biological activities. To evaluate the influence of composition on anti-inflammatory activity, cranberry fruits were collected from two major U.S. growing regions. Eight extracts from these fruits were prepared, analyzed for phytochemical composition, and evaluated for their anti-inflammatory effects in human monocytes (THP-1 cells). The extracts varied widely in polyphenol and triterpenoid content. All were able to reduce lipopolysaccharide (LPS)-induced production of pro-inflammatory cytokine interleukin 6 (IL-6) at 100 μg/mL, with inhibition ranging between 18.8 and 48.8%. Of these, three extracts high in anthocyanins, triterpenoids, or total polyphenols decreased levels of IL-6 and tumor necrosis factor alpha (TNF-α) at concentrations of 0.1–10 μg/mL compared to LPS-exposed control. Several individual cranberry phytochemicals were also capable of reducing production of IL-6, IL-1β, and TNF-α. The data suggest that phytochemicals present in varying quantities in cranberry fruits including anthocyanins, hyperoside, ursolic acid, and corosolic acid play a role in the anti-inflammatory effects of cranberry extracts on human monocytes.

Cranberry (Vacinium macrocarpon) phytochemicals inhibit hepatic stellate cell activation and liver fibrosis

Excessive activation and proliferation of hepatic stellate cells (HSCs) is the most critical factor in liver fibrosis. Cranberry (Vaccinium macrocarpon) is berry-bearing with potential health benefits. Here, we reported the inhibitory effects of cranberry phytochemicals (CPS) on HSC activation and liver fibrogenesis. The results showed that CPS reduced cell viability and inhibited the TGFβ/Smad signaling pathway of HSCs in vitro. The therapeutic effects of CPS on HSC activation were further linked to the amelioration of CCl4-induced liver fibrosis in rats. CPS treatment reduced liver fibrosis, revived liver function (HYP, MDA, ALB, ALP, ALT, AST, and TBIL), and decreased inflammatory cytokines (IL-1, IL-6, and TNF-α) in a dose-dependent manner. Moreover, the expression levels of the TGFβ/Smad signaling pathway related genes, including TGF-β1, Smad2/3, p-Smad2/3, Col1α1, and α-SMA, were down-regulated by CPS. It is suggested that CPS may inhibit HSC activation and liver fibrosis by reducing the expression of inflammatory cytokines and inhibiting the TGFβ/Smad signaling pathway.

Cranberry Polyphenols: Natural Weapons against Dental Caries.

Bioactive polyphenol components of cranberry (Vaccinium macrocarpon) are known to have virulence attenuating effects against several cariogenic virulence properties responsible for dental caries pathogenesis. In particular, cranberry A-type proanthocyanidins and flavonols have demonstrated potent inhibitory effects against cariogenic virulence targets such as bacterial acidogenicity, aciduricity, glucan synthesis, and hydrophobicity. Cranberry phenols have the ability to disrupt these cariogenic virulence properties without being bactericidal, a key quality essential for retaining the benefits of the symbiotic resident oral microbiome and preventing the emergence of resistant microbes. This review discusses the cariostatic mechanisms of specific cranberry phytochemicals and their potential use as therapeutic agents against cariogenic bacteria in the prevention and control of dental caries.

American cranberries and health benefits - an evolving story of 25 years.

Cranberries contain various types of bioactive components. Scientists have been studying cranberries' beneficial effects on urinary tract health since the 20th century. In the 21st century, the protection provided by cranberry phytochemicals against cancer and vascular diseases has drawn more attention from researchers. Anthocyanins, procyanidins, and flavonols in cranberries were all documented to have potential effects on cancer prevention. The cardiometabolic effects of cranberries have been investigated in several clinical trials. It was found that cranberries positively affect atherosclerotic cholesterol profiles and that they reduced several cardiometabolic risk factors. Nowadays, growing evidence suggests other important roles of cranberries in maintaining digestive health. Cranberry juice or cranberries have been shown to inhibit the colonization of H. pylori in stomach, and protect against intestinal inflammation. For future research, clinical trials with improved study design are urgently needed to demonstrate cranberries' benefits on urinary tract health and cardiometabolic diseases. Hypothesis-driven studies using animals or cell culture are needed to elucidate the mechanisms of cranberries' effects on digestive health. © 2018 Society of Chemical Industry.

Atomic force microscopy-guided fractionation reveals the influence of cranberry phytochemicals on adhesion of Escherichia coli.

Cranberry juice has been long used to prevent infections because of its effect on the adhesion of the bacteria to the host surface. Proanthocyanidins (PACs) comprise of one of the major classes of phytochemicals found in cranberry, which have been extensively studied and found effective in combating adhesion of pathogenic bacteria. The role of other cranberry constituents in impacting bacterial adhesion haven't been studied very well. In this study, cranberry juice fractions were prepared, characterized and tested for their effect on the surface adhesion of the pathogenic clinical bacterial strain E. coli B78 and non-pathogenic control E. coli HB101. The preparations tested included crude cranberry juice extract (CCE); three fractions containing flavonoid classes including proanthocyanidins, anthocyanins and flavonols; selected sub-fractions, and commercially available flavonol glycoside, quercetin-3-O-galactoside. Atomic force microscopy (AFM) was used to quantify the adhesion forces between the bacterial surface and the AFM probe after the treatment with the cranberry fractions. Adhesion forces of the non-pathogenic, non fimbriated lab strain HB101 are small (average force 0.19 nN) and do not change with cranberry treatments, whereas the adhesion forces of the pathogenic, Dr adhesion E. coli strain B78 (average force of 0.42 nN) show a significant decrease when treated with cranberry juice extract or fractions (average force of 0.31 nN, 0.37 nN and 0.39 nN with CCE, Fraction 7 and Fraction 4 respectively). In particular, the fractions that contained flavonols in addition to PACs were more efficient at lowering the force of adhesion (average force of 0.31 nN-0.18 nN between different sub-fractions containing flavonols and PACs). The sub-fractions containing flavonol glycosides (from juice, fruit and commercial quercetin) all resulted in reduced adhesion of the pathogenic bacteria to the model probe. This strongly suggests the anti adhesive role of other classes of cranberry compounds in conjunction with already known PACs and may have implications for development of alternative anti bacterial treatments.

Iron sequestration is not the main mechanism in the inhibition of Staphylococcus aureus growth by cranberry phytochemicals

Iron sequestration is not the main mechanism in the inhibition of Staphylococcus aureus growth by cranberry phytochemicals

Cranberry extract standardized for proanthocyanidins promotes the immune response of Caenorhabditis elegans to Vibrio cholerae through the p38 MAPK pathway and HSF-1.

Botanicals are rich in bioactive compounds, and some offer numerous beneficial effects to animal and human health when consumed. It is well known that phytochemicals in cranberries have anti-oxidative and antimicrobial activities. Recently, an increasing body of evidence has demonstrated that cranberry phytochemicals may have potential benefits that promote healthy aging. Here, we use Caenorhabditis elegans as a model to show that water-soluble cranberry extract standardized to 4.0% proanthocyanidins (WCESP), a major component of cranberries, can enhance host innate immunity to resist against Vibrio cholerae (V. cholerae; wild type C6706 (O1 El Tor biotype)) infection. Supplementation of WCESP did not significantly alter the intestinal colonization of V. cholerae, but upregulated the expression of C. elegans innate immune genes, such as clec-46, clec-71, fmo-2, pqn-5 and C23G10.1. Additionally, WCESP treatment did not affect the growth of V. cholerae and expression of the major bacterial virulence genes, and only slightly reduced bacterial colonization within C. elegans intestine. These findings indicate that the major components of WCESP, including proanthocyanidins (PACs), may play an important role in enhancing the host innate immunity. Moreover, we engaged C. elegans mutants and identified that the p38 MAPK signaling, insulin/IGF-1 signaling (IIS), and HSF-1 play pivotal roles in the WCESP-mediated host immune response. Considering the level of conservation between the innate immune pathways of C. elegans and humans, the results of this study suggest that WCESP may also play an immunity-promoting role in higher order organisms.

Consumption of cranberry polyphenols enhances human γδ-T cell proliferation and reduces the number of symptoms associated with colds and influenza: a randomized, placebo-controlled intervention study

BackgroundOur main objective was to evaluate the ability of cranberry phytochemicals to modify immunity, specifically γδ-T cell proliferation, after daily consumption of a cranberry beverage, and its effect on health outcomes related to cold and influenza symptoms.MethodsThe study was a randomized, double-blind, placebo-controlled, parallel intervention. Subjects drank a low calorie cranberry beverage (450 ml) made with a juice-derived, powdered cranberry fraction (n = 22) or a placebo beverage (n = 23), daily, for 10 wk. PBMC were cultured for six days with autologous serum and PHA-L stimulation. Cold and influenza symptoms were self-reported.ResultsThe proliferation index of γδ-T cells in culture was almost five times higher after 10 wk of cranberry beverage consumption (p <0.001). In the cranberry beverage group, the incidence of illness was not reduced, however significantly fewer symptoms of illness were reported (p = 0.031).ConclusionsConsumption of the cranberry beverage modified the ex vivo proliferation of γδ-T cells. As these cells are located in the epithelium and serve as a first line of defense, improving their function may be related to reducing the number of symptoms associated with a cold and flu.Trial registrationClinicalTrials.gov Identifier: NCT01398150.

Cranberry Proanthocyanidins: Natural Weapons against Periodontal Diseases

Cranberry ( Vaccinium macrocarpon ) is known to have a beneficial effect on several aspects of human health. Proanthocyanidins (PACs), the most abundant flavonoids extracted from red cranberry fruits, have been reported to possess antimicrobial, antiadhesion, antioxidant, and anti-inflammatory properties. Recent in vitro studies have shown that cranberry PACs may be potential therapeutic agents for the prevention and management of periodontitis, an inflammatory disease of bacterial origin affecting tooth-supporting tissues. After presenting an overview of cranberry phytochemicals and their potential for human health benefits, this review will focus on the effects of cranberry PACs on connective tissue breakdown and alveolar bone destruction, as well as their potential for controlling periodontal diseases. Possible mechanisms of action of cranberry PACs include the inhibition of (i) bacterial and host-derived proteolytic enzymes, (ii) host inflammatory response, and (iii) osteoclast differentiation and activity. Given that cranberry PACs have shown interesting properties in in vitro studies, clinical trials are warranted to better evaluate the potential of these molecules for controlling periodontal diseases.

Cranberry Phytochemicals Inhibit Glycation of Human Hemoglobin and Serum Albumin by Scavenging Reactive Carbonyls

The objective of this study was to investigate the inhibitory effects of cranberry phytochemicals on protein glycation. Cranberries were purified to yield a sugar‐free powder, which was fractionated into ethyl acetate fraction and water fraction. Water fraction was separated into water fraction‐I, II, and III. Antiglycation activities were tested using glycated hemoglobin (HbA1c), human serum albumin (HSA) ‐glucose, and HSA‐methylglyoxal assays. Cranberry powder and its fractions significantly inhibited the formation of HbA1c by 41.7–81.9 %. The concentrations of cranberry phytochemicals required to inhibit 50% of albumin glycation (EC50) in HSA‐glucose assay was lower than aminoguanidine except for water fraction‐I. The cranberry powder and fractions inhibited glycation of HSA by methylglyoxal. Cranberry phytochemicals scavenged 21.6–89.3% methylglyoxal within 6 hours. Fractions enriched with procyanidins showed higher antiglycation activities. Epicatechin, the constituent unit of procyanidins, were incubated with methylglyoxal and glyoxal at pH 7.4. Five adducts were detected and their structures were tentatively identified using HPLC‐ESI‐MSn. In conclusion, cranberry phytochemicals inhibited glycation of human hemoglobin and serum albumin by scavenging reactive carbonyls. This research is supported in part by Ocean Spray Cranberries, Inc.

Cranberry phytochemicals inhibit glycation of human hemoglobin and serum albumin by scavenging reactive carbonyls

Protein glycation caused by sugars and reactive carbonyls is a contributing factor to diabetic complications, aging, and other chronic diseases. The objective of this study was to investigate the inhibitory effects of cranberry phytochemicals on protein glycation. Cranberries, purified to yield sugar-free phytochemical powder, were fractionated into ethyl acetate and water fractions. Water fraction was further separated into water fraction I, II, and III on a Sephadex LH-20 column. Cranberry phytochemical powder and its fractions significantly inhibited the formation of glycated hemoglobin. The concentrations of cranberry phytochemicals required to inhibit 50% of albumin glycation (EC(50)) in albumin-glucose assay were lower than that of aminoguanidine except for water fraction I. Cranberry phytochemicals inhibited glycation of human serum albumin mediated by methylglyoxal, but the EC(50) were higher than that of aminoguanidine. Carbonyl scavenging assay showed that water fraction II scavenged 89.3% of methylglyoxal at 6 h of reaction. Fractions enriched with procyanidins showed higher antiglycation activities, suggesting procyanidins were the major active components. The hypothesis whether cranberry procyanidins scavenged reactive carbonyls by forming adducts was tested. Epicatechin was used as a model compound to react with methylglyoxal and glyoxal at pH 7.4. Five adducts were detected and their structures were tentatively identified using HPLC-ESI-MS/MS.

Cranberry phytochemicals act as non‐microbial antigens for different types of human peripheral blood mononuclear cells

To determine whether specific families of phytochemicals are able to interact with human peripheral blood mononuclear cell (PBMC) receptors and initiate an immune response, isolated human PBMC were incubated with three different extracts of cranberries representing anthocyanins, proanthocyanidins, or polyphenols. Proliferation of cells upon ex vivo stimulation and surface marker expression were measured by flow cytometry. The fraction containing mainly proanthocyanidins caused proliferation and activation of ãä T cells, as well as the activation of B cells. The fraction containing mainly anthocyanins slightly activated NK cells detected as an increased expression of NKG2D on NK cell surfaces. The polyphenol fraction increased B cell proliferation, and markedly increased expression of VLA‐1, about 10 fold, on monocytes. VLA‐1 is a cell adhesion molecule. PBMC secreted a number of cytokines in response to incubation with the cranberry fractions; the proanthocyanidin‐containing fraction having the greatest stimulatory effect. These results suggest that cranberry phytochemicals have the potential to immuno‐modulate in a variety of ways. Supported by Ocean Spray Cranberries, Inc and FAES

Cranberry phytochemicals modify human immune function and appear to reduce the severity of cold and flu symptoms

Proanthocyanidins (PACs) are complex molecules that have been suggested to have health benefits, most recently in relation to immune function. Cranberries are an excellent source of PACs, possessing both the A‐ and B‐type linkages, and in addition, contain other polyphenols. We hypothesized that the PAC contained in cranberries could modify specific human immune cells in vivo, particularly the γδ T cell which is known to recognize and respond to PACs in vitro. This effect is thought to be related to non‐microbial priming of the immune cells by the phytochemicals. In a randomized, double‐blind, placebo‐controlled human study, 10 weeks of consumption of a beverage containing a powder derived from cranberries resulted in a fivefold increase in proliferation of γδ T cells ex vivo, a 30% increase in NK cell proliferation and a 20% reduction in IL‐17 secretion. Subjects consuming the beverage made with cranberry powder had fewer cold and flu symptoms (p=0.010) when compared to those consuming the placebo. The incidence of illnesses, total missed work days, and decrease in activities tended to be lower, however actual values were not significantly different from placebo. Consumption of cranberry phytochemicals was shown to modify certain aspects of immune function, suggesting that consuming cranberries may help support immune health. Supported by Ocean Spray Cranberries, Inc and FAES

North American Cranberry (Vaccinium Macrocarpon) Stimulates Apoptotic Pathways in DU145 Human Prostate Cancer Cells In Vitro

Diets rich in fruits and vegetables have been shown to improve patient prognosis in a variety of cancers, a benefit partly derived from phytochemicals, many of which target cell death pathways in tumor cells. Cranberries (Vaccinium macrocarpon) are a phytochemical-rich fruit containing a variety of polyphenolic compounds. As flavonoids have been shown to induce apoptosis in human tumor cells, this study investigated the hypothesis that cranberry-mediated cytotoxicity in DU145 human prostate adenocarcinoma cells involves apoptosis. The results showed that induction of apoptosis in these cells occurred in response to treatment with whole cranberry extract and occurred through caspase-8 mediated cleavage of Bid protein to truncated Bid resulting in cytochrome-C release from the mitochondria. Subsequent activation of caspase-9 ultimately resulted in cell death as characterized by DNA fragmentation. Increased Par-4 protein expression was observed, and this is suggested to be at least partly responsible for caspase-8 activation. Proanthocyanidin-enriched and flavonol-enriched fractions of cranberry also increased caspase-8 and caspase-9 activity, suggesting that these compounds play a possible role in apoptosis induction. These findings indicate that cranberry phytochemicals can induce apoptosis in prostate cancer cells in vitro, and these findings further establish the potential value of cranberry phytochemicals as possible agents against prostate cancer.

Phytochemicals of Cranberries and Cranberry Products: Characterization, Potential Health Effects, and Processing Stability

Emerging evidence is elucidating how non-nutrient phytochemicals underlie the health promotion afforded by fruits and vegetables. This review focuses on Vaccinium macrocarpon, the American cranberry, compiling a comprehensive list of its known phytochemical components, and detailing their prevalence in cranberry fruit and its products. Flavonoids, especially colored anthocyanins, abundant flavonols, and unique proanthocyanidins, have attracted major research attention. Other notable active components include phenolic acids, benzoates, hydroxycinnamic acids, terpenes and organic acids. Health effects of cranberries, cranberry products, and isolated cranberry components in humans and animals, as well as in vitro, are debated. Evidence for protection from several bacterial pathogens, cancer, cardiovascular disease, and inflammation is compelling, while neuroprotection and anti-viral activity also have begun to draw new consideration. Emerging bioavailability data is considered and potential molecular mechanisms are evaluated, linking phytochemicals to health effects through their biochemical properties and reactions. Finally, the effects of processing and storage on cranberry phytochemicals is discussed, with a focus on identifying research gaps and novel means to preserve their natural, health-promoting components.

Anticancer activities of cranberry phytochemicals: An update

Studies employing mainly in vitro tumor models show that extracts and compounds isolated from cranberry fruit (Vaccinium macrocarpon) inhibit the growth and proliferation of several types of tumor including breast, colon, prostate, and lung. Proanthocyanidin oligomers, flavonol and anthocyanin glycosides and triterpenoids are all likely contributors to the observed anticancer properties and may act in a complementary fashion to limit carcinogenesis. Possible chemopreventive mechanisms of action by cranberry phytochemicals include induction of apoptosis in tumor cells, reduced ornithine decarboxylase activity, decreased expression of matrix metalloproteinases associated with prostate tumor metastasis, and anti-inflammatory activities including inhibition of cyclooxygenases. A review of recent studies suggests a potential role for cranberry as a dietary chemopreventive and provides direction for future research.

Cranberry and its phytochemicals: a review of in vitro anticancer studies.

This article reviews the existing research on the anticancer properties of cranberry fruit and key phytochemicals that are likely contributors to chemoprevention. Results from in vitro studies using a variety of tumor models show that polyphenolic extracts from Vaccinium macrocarpon inhibit the growth and proliferation of breast, colon, prostate, lung, and other tumors, as do flavonols, proanthocyanidin oligomers, and triterpenoids isolated from the fruit. The unique combination of phytochemicals found in cranberry fruit may produce synergistic health benefits. Possible chemopreventive mechanisms of action by cranberry phytochemicals include induction of apoptosis in tumor cells, reduced ornithine decarboxylase activity, decreased expression of matrix metalloproteinases associated with prostate tumor metastasis, and antiinflammatory activities including inhibition of cyclooxygenases. These findings suggest a potential role for cranberry as a dietary chemopreventive and provide direction for future research.

Cranberry Phytochemicals: Isolation, Structure Elucidation, and Their Antiproliferative and Antioxidant Activities

Bioactivity-guided fractionation of cranberries was used to determine the chemical identity of bioactive constituents. Twenty compounds were isolated using gradient solvent fractionation, silica gel and ODS columns, and preparative RP-HPLC. Their chemical structures were identified using HR-MS, 1D and 2D NMR, and X-ray diffraction analysis. Antiproliferative activities of isolated compounds against HepG2 human liver cancer and MCF-7 human breast cancer cells were evaluated. Among the compounds isolated, ursolic acid, quercetin, and 3,5,7,3',4'-pentahydroxyflavonol-3-O-beta-D-glucopyranoside showed potent antiproliferative activities against HepG2 cell growth, with EC50 values of 87.4 +/- 2.7, 40.9 +/- 1.1, and 49.2 +/- 4.9 microM, respectively. Ursolic acid, quercetin, and 3,5,7,3',4'-pentahydroxyflavonol-3-O-beta-D-glucopyranoside showed potent inhibitory activity toward the proliferation of MCF-7 cells, with EC50 values of 11.7 +/- 0.1, 137.5 +/- 2.6, and 23.9 +/- 3.9 microM, respectively. Quercetin, 3,5,7,3',4'-pentahydroxyflavonol-3-O-beta-D-glucopyranoside, 3,5,7,3',4'-pentahydroxyflavonol-3-O-beta-D-galactopyranoside, and 3,5,7,3',4'-pentahydroxyflavonol-3-O-alpha-l-arabinofuranoside showed potent antioxidant activities, with EC50 values of approximately 10 microM. These results showed cranberry phytochemical extracts have potent antioxidant and antiproliferative activities.