Cranberry polyphenols‐gut microbiota interactions and potential health benefits: An updated review

Effects of Cranberry Extract (Vaccinium macrocarpon) Supplementation on Lipid Peroxidation and Inflammation in Patients with Chronic Kidney Disease (Stages 3-4): A Randomized Controlled Trial

Background

Growing evidence suggests that bioactive compounds in berry fruits may mitigate inflammation in patients with chronic kidney disease (CKD).

Objectives

To evaluate cranberry (Vaccinium macrocarpon) supplementation effects on modulation of transcription factors involved in inflammation and oxidative stress in nondialysis (stages 3 and 4) patients with CKD. Design/Participants. A randomized, double-blind, placebo-controlled study was performed with 30 patients to receive capsules containing cranberry extract (1000 mg/day) or placebo (1000 mg/day of corn starch) for two months. Measurements. The mRNA expression of nuclear factor-erythroid 2-related factor-2 (Nrf2) and nuclear factor-kB (NF-kB) was evaluated in peripheral blood mononuclear cells (PBMCs) by quantitative real-time polymerase chain reaction. Thiobarbituric acid reactive substances (TBARS) were measured in the plasma to assess oxidative stress. Interleukin-6 (IL-6) plasma levels were assessed by enzyme-linked immunosorbent assay and C-reactive protein (CRP) by immunoturbidimetric method.

Results

Twenty-five patients completed the study: 12 in the cranberry group (56.7 ± 7.5 years and body mass index (BMI) of 29.6 ± 5.5 kg/m2) and 13 in the placebo group (58.8 ± 5.1 years and BMI 29.8 ± 5.4 kg/m2). There were no differences in NF-kB or Nrf2 mRNA expressions (p = 0.99 and p = 0.89) or TBARS, CRP, and IL-6 plasma levels after cranberry supplementation.

Conclusions

The cranberry extract administration (1000 mg/day) did not affect Nrf2 and NF-kB mRNA expression, oxidative stress, or inflammatory markers levels in nondialysis CKD patients. This trial is registered with NCT04377919.

Exploration of natural flavones' bioactivity and bioavailability in chronic inflammation induced-type-2 diabetes mellitus

Diabetes, being the most widespread illness, poses a serious threat to global public health. It seems that inflammation plays a critical role in the pathophysiology of diabetes. This review aims to demonstrate a probable link between type 2 diabetes mellitus (T2DM) and chronic inflammation during its development. Additionally, the current review examined the bioactivity of natural flavones and the possible molecular mechanisms by which they influence diabetes and inflammation. While natural flavones possess remarkable anti-diabetic and anti-inflammatory bioactivities, their therapeutic use is limited by the low oral bioavailability. Several factors contribute to the low bioavailability, including poor water solubility, food interaction, and unsatisfied metabolic behaviors, while the diseases (diabetes, inflammation, etc.) causing even less bioavailability. Throughout the years, different strategies have been developed to boost flavones' bioavailability, including structural alteration, biological transformation, and innovative drug delivery system design. This review addresses current advancements in improving the bioavailability of flavonoids in general, and flavones in particular. Clinical trials were also analyzed to provide insight into the potential application of flavonoids in diabetes and inflammatory therapies.

Beneficial effect of vinegar consumption associated with regulating gut microbiome and metabolome

Vinegar is used as fermented condiment and functional food worldwide. Vinegar contains many nutrients and bioactive components, which exhibits health benefits. In this study, the potential effects of Shanxi aged vinegar (SAV) on gut microbiome and metabolome were explored in normal mice. The levels of inflammatory factors were significantly decreased in SAV-treated mice. Immunoglobulin, NK cells and CD20 expression were significantly increased after SAV administration. In addition, SAV intake altered gut microbiota structure by up-regulating Verrucomicrobia, Akkermansia, Hungatella and Alistipes, and down-regulating Firmicutes, Lachnospiraceae_NK4A136_group and Oscillibacter. The differential metabolites were mainly included amino acids, carbohydrates and bile acids. Furthermore, after SAV intake, Verrucomicrobia, and Akkermansia closely impacted the related gut metabolites. These alterations of gut microbiota-related metabolism further modulated some immunoregulatory and inflammatory factors, and confer potential health benefits. Our results imply that vinegar consumption has beneficial effects on regulating gut microbiome and metabolome.

Polysaccharides from the hard shells of Juglans regia L. modulate intestinal function and gut microbiota in vivo

This study aimed to investigate the modulatory effects of polysaccharides from the hard shells ofJuglans regiaL. (JRP) on intestinal function and gut microbiota of mice. The results showed that JRP could increase the colonic length and colonic index, and ameliorate the histological characteristics of colon. JRP had a positive effect on immunity of mice by improving immune organ indexes. Owing to enhancement of intestinal peristalsis and increase of colonic fecal moisture by JRP, the defecation time was significantly reduced. After gastrointestinal digestion and absorption, JRP was metabolized by intestinal microorganisms to produce short chain fatty acids, thereby lowering the pH of intestine. Through microbial community analysis, the composition of gut microbiota was modulated by JRPvia increasing theabundances of beneficial bacteriaand decreasing the richness of harmful bacteria. This study suggests that JRP can be served as an excellent prebiotic to promote intestinal health.

The role of intestinal microbiota and microRNAs in the anti-inflammatory effects of cranberry: from pre-clinical to clinical studies

Cranberries have known anti-inflammatory properties, which extend their benefits in the context of several chronic diseases. These benefits highly rely on the polyphenol profile of cranberries, one of few foods rich in A-type proanthocyanidin (PAC). A-type PAC comprises flavan-3-ol subunits with an additional interflavan ether bond in the conformational structure of the molecule, separating them from the more commonly found B-type PAC. PACs with a degree of polymerization higher than three are known to reach the colon intact, where they can be catabolyzed by the gut microbiota and biotransformed into lower molecular weight organic acids that are available for host absorption. Gut microbiota-derived metabolites have garnered much attention in the past decade as mediators of the health effects of parent compounds. Though, the mechanisms underlying this phenomenon remain underexplored. In this review, we highlight emerging evidence that postulates that polyphenols, including ones derived from cranberries, and their metabolites could exert anti-inflammatory effects by modulating host microRNAs. Our review first describes the chemical structure of cranberry PACs and a pathway for how they are biotransformed by the gut microbiota. We then provide a brief overview of the benefits of microbial metabolites of cranberry in the intestinal tract, at homeostasis and in inflammatory conditions. Finally, we discuss the role of microRNAs in intestinal health and in response to cranberry PAC and how they could be used as targets for the maintenance of intestinal homeostasis. Most of this research is pre-clinical and we recognize that conducting clinical trials in this context has been hampered by the lack of reliable biomarkers. Our review discusses the use of miRNA as biomarkers in this context.

The Impact of Phytochemicals in Obesity-Related Metabolic Diseases: Focus on Ceramide Metabolism

The prevalence of obesity and related metabolic diseases has increased dramatically worldwide. As obesity progresses, various lipid species accumulate in ectopic tissues. Amongst them, ceramides-a deleterious sphingolipid species-accumulate and cause lipotoxicity and metabolic disturbances. Dysregulated ceramide metabolism appears to be a key feature in the pathogenesis of obesity-related metabolic diseases. Notably, dietary modification might have an impact on modulating ceramide metabolism. Phytochemicals are plant-derived compounds with various physiological properties, which have been shown to protect against obesity-related metabolic diseases. In this review, we aim to examine the impact of a myriad of phytochemicals and their dietary sources in altering ceramide deposition and ceramide-related metabolism from in vitro, in vivo, and human clinical/epidemiological studies. This review discusses how numerous phytochemicals are able to alleviate ceramide-induced metabolic defects and reduce the risk of obesity-related metabolic diseases via diverse mechanisms.

Gut microbiota and transcriptome profiling revealed the protective effect of aqueous extract of Tetrastigma hemsleyanum leaves on ulcerative colitis in mice

Tetrastigma hemsleyanum, a traditional Chinese medicinal plant, possesses various biological activities, including anti-inflammatory and immunomodulatory functions. The purpose of this study was to determine the alleviating effect of the water extract of Tetrastigma hemsleyanum leaves (THLW) on ulcerative colitis (UC) and its relationship with gut microbiota. The administration of THLW significantly decreased the severity of dextran sulfate sodium (DSS)-induced intestinal damage, as demonstrated by the stabilization of body weight and colon length, and decreased disease activity index (DAI) and histological scores. THLW also decreased NF-κB protein expression in colon tissues and reduced the serum levels of IL-6, IL-1β, and TNF-α. Further co-housing experiment confirmed that the anti-UC effect of THLW was possibly by regulating the structure and composition of gut microbiota, including increasing the abundance of Oscillospiraceae, Prevotellaceae and Corynebacterium. Additionally, the expression of genes related to inflammation and immunity was also regulated by THLW treatment as evidenced by transcriptome analysis. These results suggested that the protective effect of THLW on DSS-induced colitis was mediated by alleviating inflammation and modulating the microbiota composition. This work proved the potent protective effects of THLW treatment on colitis and may have potential for UC relief.

Recent advances in the biosynthesis, bioavailability, toxicology, pharmacology, and controlled release of citrus neohesperidin

Neohesperidin (hesperetin 7-O-neohesperidoside), a well-known flavanone glycoside widely found in citrus fruits, exhibits a variety of biological activities, with potential applications ranging from food ingredients to therapeutics. The purpose of this manuscript is to provide a comprehensive overview of the chemical, biosynthesis, and pharmacokinetics profiles of neohesperidin, as well as the therapeutic effects and mechanisms of neohesperidin against potential diseases. This literature review covers a wide range of pharmacological responses elicited by Neohesperidin, including neuroprotective, anti-inflammatory, antidiabetic, antimicrobial, and anticancer activities, with a focus on the mechanisms of those pharmacological responses. Additionally, the mechanistic pathways underlying the compound's osteoporosis, antiulcer, cardioprotective, and hepatoprotective effects have been outlined. This review includes detailed illustrations of the biosynthesis, biopharmacokinetics, toxicology, and controlled release of neohesperidine. Neohesperidin demonstrated a broad range of therapeutic and biological activities in the treatment of a variety of complex disorders, including neurodegenerative, hepato-cardiac, cancer, diabetes, obesity, infectious, allergic, and inflammatory diseases. Neohesperidin is a promising therapeutic candidate for the management of various etiologically complex diseases. However, further in vivo and in vitro studies on mechanistic potential are required before clinical trials to confirm the safety, bioavailability, and toxicity profiles of neohesperidin.

The anti-diabetic activity of polyphenols-rich vinegar extract in mice via regulating gut microbiota and liver inflammation

Polyphenols in vinegar are benefit to human health. The purpose of this research was to identify the polyphenols-rich vinegar extract (VE) and evaluate the anti-diabetic mechanisms in vivo. The results showed that 29 polyphenols were identified by UPLC-Q/Trap-MS/MS analysis. 4-Hydroxybenzoic acid, ferulic acid, and ethyl ferulate were the main polyphenols. In addition, VE relieved the symptoms of type 2 diabetes mellitus (T2DM) by down-regulating blood glucose and lipemia. VE reduced inflammation by inhibiting TLR4/NF-κB signaling pathway. Furthermore, VE treatment restored gut microbiota dysbiosis (upregulating Bacteroidetes, Lactobacillus, Bifidobacterium, and Bacteroides and downregulating Firmicutes, Proteobacteria, and Enterorhabdus abundances), and increased short chain fatty acids contents in diabetic mice, which participated in anti-diabetic effect of VE by correlation analysis. These findings suggest that VE may be a candidate for T2DM intervention by regulating gut microbiota and inflammation.

Rhodomyrtus tomentosa (Ait.) Hassk fruit phenolic-rich extract mitigates intestinal barrier dysfunction and inflammation in mice

In this study, the mitigative effect of Rhodomyrtus tomentosa (Ait.) Hassk fruit extract rich in phenolic compounds (RTE) on high fat diet (HFD)-induced intestinal barrier dysfunction of mice and the underlying mechanism were explored. The results revealed that RTE supplementation obviously improved gut microbiota dysbiosis induced by HFD, which was evidenced by elevated alpha diversity, suppressed Firmicutes/Bacteroidetes ratio, enriched short-chain fatty acid-producing bacteria (Odoribacter, Parabacteroides, Blautia and Akkermansia), and depleted harmful bacteria (Helicobacter, norank_f_ Desulfovibrionaceae and Mucispirillum). RTE intervention mitigated intestinal barrier dysfunction and inflammation by elevating tight junction proteins expression levels and decreasing proinflammatory cytokines levels. Furthermore, RTE administration inhibited the HFD-induced trigger of the lipopolysaccharide-toll-like receptor 4-nuclear factor kappa-B (LPS-TLR4-NF-κB) pathway in colonic tissue. Therefore, RTE supplementation may be an effective way to protect the intestinal tract in HFD-induced obese individuals.

Kaempferol and atherosclerosis: From mechanism to medicine

Natural products possess pleiotropic cardiovascular protective effects owing to their anti-oxidation, anti-inflammation and anti-thrombotic properties. Kaempferol, (3,5,7-trihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one), is a kind of naturally occurring flavonoid existing in many common fruits and vegetables (e.g., onions, broccoli, strawberries and grapes) and particularly in traditional Chinese medicine as exemplified by Ginkgo biloba. Epidemiological, preclinical and clinical studies have revealed an inverse association between the consumption of kaempferol-containing foods and medicines and the risk of developing cardiovascular diseases. Numerous translational studies in experimental animal models and cultured cells have demonstrated a wide range of pharmacological activities of kaempferol. In this article, we reviewed the antioxidant, anti-inflammatory and cardio-protective activities of kaempferol and elucidated the potential molecular basis of the therapeutic capacity of kaempferol by focusing on its anti-atherosclerotic effects. Overall, the review presents the health benefits of kaempferol-containing plants and medicines and reflects on the potential of kaempferol as a possible drug candidate to prevent and treat atherosclerosis, the underlying pathology of most cardiovascular diseases.

Modulation of integrin receptor by polyphenols: Downstream Nrf2-Keap1/ARE and associated cross-talk mediators in cardiovascular diseases

As a group of heterodimeric and transmembrane glycoproteins, integrin receptors are widely expressed in various cell types overall the body. During cardiovascular dysfunction, integrin receptors apply inhibitory effects on the antioxidative pathways, including nuclear factor erythroid 2-related factor 2 (Nrf2)-Kelch like ECH Associated Protein 1 (Keap1)/antioxidant response element (ARE) and interconnected mediators. As such, dysregulation in integrin signaling pathways influences several aspects of cardiovascular diseases (CVDs) such as heart failure, arrhythmia, angina, hypertension, hyperlipidemia, platelet aggregation and coagulation. So, modulation of integrin pathway could trigger the downstream antioxidant pathways toward cardioprotection. Regarding the involvement of multiple aforementioned mediators in the pathogenesis of CVDs, as well as the side effects of conventional drugs, seeking for novel alternative drugs is of great importance. Accordingly, the plant kingdom could pave the road in the treatment of CVDs. Of natural entities, polyphenols are multi-target and accessible phytochemicals with promising potency and low levels of toxicity. The present study aims at providing the cardioprotective roles of integrin receptors and downstream antioxidant pathways in heart failure, arrhythmia, angina, hypertension, hyperlipidemia, platelet aggregation and coagulation. The potential role of polyphenols has been also revealed in targeting the aforementioned dysregulated signaling mediators in those CVDs.

Enzymatic acylation of raspberry anthocyanin: Evaluations on its stability and oxidative stress prevention

Raspberry anthocyanins were isolated and purified by XAD-7HP macroporous resin and silica gel column chromatography. Anthocyanins were then acylated with methyl salicylate as catalyzed by lipase under reduced pressure, and the conversion rate was 84.26%. LC-MS and NMR were used to identify the structure, and the stability, antioxidant capacity and protective ability of the acylated anthocyanins against oxidative damage were determined. The results showed that cyanindin-3-O-glucoside (C3G) was the primary anthocyanin in raspberry, and the binding site of acylation was on the glucoside C-6, and the product was cyanidin-3-(6-salicyloyl) glucoside (C3-6(S) G). After acylation, its stability in light, heat and oxidation environments could be significantly improved, and acylated ACN showed insignificant changes in antioxidant capacities to scavenge DPPH and ABTS free radicals, as well as oxygen free radical absorptive capacity (ORAC). And it could also effectively prevent the release of ROS caused by oxidative damage and alleviate oxidative stress damage.

Dietary proanthocyanidins on gastrointestinal health and the interactions with gut microbiota

Many epidemiological and experimental studies have consistently reported the beneficial effects of dietary proanthocyanidins (PAC) on improving gastrointestinal physiological functions. This review aims to present a comprehensive perspective by focusing on structural properties, interactions and gastrointestinal protection of PAC. In brief, the main findings of this review are summarized as follows: (1) Structural features are critical factors in determining the bioavailability and subsequent pharmacology of PAC; (2) PAC and/or their bacterial metabolites can play a direct role in the gastrointestinal tract through their antioxidant, antibacterial, anti-inflammatory, and anti-proliferative properties; (3) PAC can reduce the digestion, absorption, and bioavailability of carbohydrates, proteins, and lipids by interacting with them or their according enzymes and transporters in the gastrointestinal tract; (4). PAC showed a prebiotic-like effect by interacting with the microflora in the intestinal tract, and the enhancement of PAC on a variety of probiotics, such as Bifidobacterium spp. and Lactobacillus spp. could be associated with potential benefits to human health. In conclusion, the potential effects of PAC in prevention and alleviation of gastrointestinal diseases are remarkable but clinical evidence is urgently needed.

Characterization of PACs profile and bioactivity of a novel nutraceutical combining cranberry extracts with different PAC-A oligomers, D-mannose and ascorbic acid: An in vivo/ex vivo evaluation of dual mechanism of action on intestinal barrier and urinary epithelium

In this paper, an A-type procyanidin (PAC)-rich cranberry extract (CB-B) was obtained mixing different extracts and was formulated with D-mannose and ascorbic acid to obtain a novel nutraceutical (URO-F) aimed at preventing non-complicated bacterial urinary tract infections (UTIs). To assess the bioactivity of CB-B and URO-F, urine samples collected from six healthy volunteers undergoing a 2-days oral consumption of 0.41 g/day of CB-B or 10 g/day of URO-F (corresponding to 72 mg/day of PACs) were tested against uropathogenic E. coli (UPEC) incubated on urinary bladder epithelial cells (T24). Urinary markers of CB-B and URO-F consumption were assessed in the same urine output by UPLC-QTOF-based untargeted metabolomics approach. CB-B and URO-F were evaluated for their ability to promote the intestinal barrier function by restoring the trans-epithelial electrical resistance (TEER) and to inhibit the production of inflammatory cytokines in intestinal epithelial Caco2 cells. CB-B was characterized by a high PAC-A content (70% of total PACs) and a broad distribution of different PACs polymers (dimers-hexamers). Urine from subjects consuming CB-B and URO-F showed a significant effect in reducing the adhesion of UPEC to urothelium in vitro, supporting their efficacy as anti-adhesive agents after oral intake. CB-B inhibited the release of cytokine IL-8, and both products were effective in restoring the TEER. Overall, our results show that the beneficial effects of CB-B and URO-F on UTIs are not only due to the antiadhesive activity of cranberry on UPEC in the urothelium, but also to a multi-target activity involving anti-inflammatory and permeability-enhancing effects on intestinal epithelium.