Blueberry Consumption Affects Serum Uric Acid Concentrations in Older Adults in a Sex-Specific Manner

Potential of dietary polyphenols for protection from age-related decline and neurodegeneration: a role for gut microbiota?

Many epidemiological studies have shown the beneficial effects of a largely plant-based diet, and the strong association between the consumption of a Mediterranean-type diet with healthy aging including a lower risk of cognitive decline. The Mediterranean diet is characterized by a high intake of olive oil, fruits and vegetables and is rich in dietary fiber and polyphenols - both of which have been postulated to act as important mediators of these benefits. Polyphenols are large molecules produced by plants to protect them from environmental threats and injury. When ingested by humans, as little as 5% of these molecules are absorbed in the small intestine with the majority metabolized by the gut microbiota into absorbable simple phenolic compounds. Flavan-3-ols, a type of flavonoid, contained in grapes, berries, pome fruits, tea, and cocoa have been associated with many beneficial effects on several risk factors for cardiovascular disease, cognitive function and brain regions involved in memory formation. Both preclinical and clinical studies suggest that these brain and heart benefits can be attributed to endothelial vascular effects and anti-inflammatory properties among others. More recently the gut microbiota has emerged as a potential modulator of the aging brain and intriguingly polyphenols have been shown to alter microbiota composition and be metabolized by different microbial species. However, there is a need for well controlled studies in large populations to identify predictors of response, particularly given the vast inter-individual variation of human gut microbiota.

Comprehensive Analysis of Highbush Blueberry Plants Propagated In Vitro and Conventionally

In vitro culture allows the production of numerous plants with both desirable and undesirable traits. To investigate the impact of the propagation method on highbush blueberry plants, an analysis was performed on four groups of differentially propagated plants: in vitro with axillary (TC-Ax) or adventitious shoots (TC-Ad), conventionally (SC) and using a mixed method (TC/SC). The analysis included plant features (shoot length and branching, chlorophyll and fluorescence and DNA methylation) and fruit properties (antioxidant compounds). The data obtained indicated significant differences between plants propagated conventionally and in vitro, as well as variations among plants derived from in vitro cultures with different types of explants. SC plants generally exhibited the lowest values of morphological and physiological parameters but produced fruits richest in antioxidant compounds. TC/SC plants were dominant in length, branching and fluorescence. Conversely, TC-Ax plants produced fruits with the lowest levels of antioxidant compounds. The methylation-sensitive amplified polymorphism (MSAP) technique was employed to detect molecular differences. TC-Ad plants showed the highest methylation level, whereas SC plants had the lowest. The overall methylation level varied among differentially propagated plants. It can be speculated that the differences among the analysed plants may be attributed to variations in DNA methylation.

The power of berries against cardiovascular diseases

Cardiovascular diseases (CVDs) pose a serious threat to human health and incidence is increasing gradually. Nutrition has an important impact on the prophylaxis and progression of CVD. In this article, general attention is drawn to the possible positive effects of berries on CVD. Polyphenols have beneficial effects on the vascular system by inhibiting low-density lipoprotein oxidation and platelet aggregation, lowering blood pressure, improving endothelial dysfunction, and attenuating antioxidant defense and inflammatory responses. This review provides an overview of the effects of berries for the prevention and treatment of CVDs. Berries contain several cardioprotective antioxidants, vitamins, and numerous phytochemicals, such as phenolic compounds, that have antioxidant properties and antiplatelet activity. Phytochemical compounds in their structures can modulate dissimilar signaling pathways related to cell survival, differentiation, and growth. Important health benefits of berries include their antioxidant roles and anti-inflammatory impacts on vascular function. The effectiveness and potential of polyphenols primarily depend on the amount of bioavailability and intake. Although circulating berry metabolites can improve vascular function, their biological activities, mechanisms of action, and in vivo interactions are still unknown. Analyzing human studies or experimental studies to evaluate the bioactivity of metabolites individually and together is essential to understanding the mechanisms by which these metabolites affect vascular function.

Blueberries and their bioactives in the modulation of oxidative stress, inflammation and cardio/vascular function markers: a systematic review of human intervention studies

Blueberries represent a rich source of (poly)phenols and other bioactive compounds. Numerous in vitro and animal model studies documented the potential health-promoting properties of blueberries and blueberry-bioactives, while little is still known about their effects in humans. The objective of the present systematic review is to provide main evidence and the potential mechanisms of action of blueberry and its (poly)phenols in the regulation of markers related to oxidative stress, inflammation, vascular and cardiometabolic function in health and disease states. A total of 45 human intervention studies were included in this review. Overall, the evidence suggests that blueberries may play a role in the improvement of markers of vascular function. Their effects were observed following both post-prandial and long-term consumption, particularly in subjects with risk factors and/or disease conditions. Conversely, the conflicting results on inflammation, oxidative stress and cardiometabolic risk markers were most likely due to differences among studies in terms of study design, subject characteristics, duration of intervention, dosage, and type of biomarkers analyzed. For these reasons, high-quality, well-designed, human intervention studies are warranted to strengthen the current findings on vascular function and provide more evidence about the impact of blueberries on the different markers considered. In addition, studies focusing on the relationship between the structure and the function of (poly)phenols will be fundamental for a better comprehension of the mechanisms behind the health effects observed.

Association Between Uric Acid to HDL Cholesterol Ratio and Diabetic Complications in Men and Postmenopausal Women

AIM

Previous studies have implicated the uric acid to high-density lipoprotein cholesterol (HDL-C) ratio (UHR) was associated with type 2 diabetes. However, the association between UHR and diabetes-related vascular damages is still unclear.

METHODS

The total of 4551 patients with type 2 diabetes from the cross-sectional Environmental Pollutant Exposure and Metabolic Diseases in Shanghai study (METAL study) were enrolled. UHR was calculated as uric acid to HDL-C ratio. Cardiovascular disease (CVD) was defined as previously diagnosed with stroke, coronary heart disease, or peripheral arterial disease. Chronic kidney disease (CKD) was defined as estimated glomerular filtration rate ≤60 mL/min/1.73 m² and/or urinary albumin to creatinine ratio ≥30 mg/g. Fundus image was examined by trained individuals and degree of diabetic retinopathy (DR) was evaluated.

RESULTS

UHR was positively correlated with CVD (OR = 1.28, 95% CI: 1.02-1.61) and CKD (OR = 1.78, 95% CI: 1.39-2.27) after adjusting for all confounders. No association was found between UHR and DR. In stratified analyses, UHR was predominantly correlated with CVD in diabetic patients with age older than 65 (OR = 1.41, 95% CI: 1.08-1.85), female (OR = 1.43, 95% CI: 1.06-1.94) and BMI≥24kg/m² (OR = 1.57, 95% CI: 1.17-2.11). A 1-SD increment of UHR was also positively associated with CVD (OR 1.26, 95% CI 1.03, 1.15) and CKD (OR 1.28, 95% CI 1.20,1.39). UHR was positively associated with CKD in all subgroups analysis. No significant interaction effect was observed between UHR and all subgroup variables in CVD and CKD risk.

CONCLUSION

Our study reported a positive association between the UHR and diabetic-related vascular complications in men and postmenopausal women. The relationship between the UHR and DR seems to be uncertain and requires further investigation. And no significant interaction effect was observed between the UHR and all subgroup variables in CVD and CKD risk.

Beneficial effects of blueberry supplementation on the components of metabolic syndrome: a systematic review and meta-analysis

Metabolic syndrome (MetS) is a combination of interconnected disorders that puts a heavy burden on societies. This study investigated the impact of blueberry (BB) supplementation on components of MetS. A...

Blueberry intervention improves metabolic syndrome risk factors: systematic review and meta-analysis

Recent studies have found that blueberry supplementation can improve parameters related to metabolic syndrome (MetS); however, there is no definitive consensus. Analysis of several randomized controlled trials can demonstrate whether a reduced effect of MetS risk factors is more pronounced in individuals who received supplementation with blueberry than in individuals who did not receive this supplementation. This systematic review and meta-analysis aimed to investigate the effect of blueberry intervention on MetS risk factors, including blood pressure, anthropometric measurements, and glycemic and lipid profiles. PubMed, Scopus, Web of Science, and SciELO were systematically searched to identify relevant studies published before July 2020. To compare the effects of blueberry supplements (powder, extract, fruit, juice, or frozen) with placebo, the mean differences with 95 % confidence intervals (CI) were pooled based on the random-effects model. We classified the quality of evidence according to the GRADE approach. In total, 18 randomized controlled trials (RCTs) were included in this systematic review, and 12 studies were selected for meta-analysis. Based on the Cochrane Collaboration risk-of-bias tool, all studies were of good quality. These trials differed with regards to blueberry dosage and forms, recruited subjects, and trial duration. Meta-analyses of the data showed that blueberry intervention had a significant effect on lipid levels, decreasing total cholesterol and low-density lipoprotein (LDL) levels. We found no significant differences in the glycemic status markers and anthropometric measurements. Blueberry supplementation significantly decreased diastolic blood pressure. In conclusion, the meta-analysis showed that blueberry may be efficacious in the treatment of MetS, due to its beneficial effects on lipid and blood pressure markers.

Blueberries and cardiovascular disease prevention

Blueberries are a rich source of (poly)phenols, particularly anthocyanins. Epidemiological studies indicate that anthocyanin-rich foods including blueberries are associated with a reduction in the risk of cardiovascular disease. These observational findings are supported by a number of randomized-controlled trials showing improvements in biomarkers of cardiovascular disease risk. The beneficial effects of blueberry (poly)phenols are particularly clear when measuring flow-mediated dilation over various timeframes and study populations. However, other outcomes are less clear, such as effects on blood pressure, arterial stiffness and blood lipid profile. This may be due to the heterogeneity existing in study designs, such as duration of the intervention, and the health status of participants. Longer-term RCTs using gold standard methods in relevant populations which can be translated to the general public are needed to clarify and strengthen the evidence available. While circulating phenolic blueberry metabolites have been linked with improvements in vascular function, the biological activities and mechanisms of action of individual metabolites and their interaction in vivo are still unknown. Evaluating the bioactivities of metabolites alone and together, and analysing their structure-activity relationship in well-designed and physiologically relevant experimental and human studies are needed to understand the mechanisms of how these metabolites affect vascular function.

Effect of Inositol Hexaphosphate (IP6) on Serum Uric Acid in Hyperuricemic Subjects: a Randomized, Double-Blind, Placebo-Controlled, Crossover Study

Inositol hexaphosphate (IP₆), a food constituent with various health benefits, has been shown to suppress postprandial elevations of serum uric acid (SUA) levels in healthy adults by inhibiting purine nucleoside and base absorption. Here, we investigated the effect of repeated intake of IP₆ on fasting SUA levels in hyperuricemic subjects. This randomized double-blind placebo-controlled crossover design study included 31 asymptomatic hyperuricemic subjects (fasting SUA level > 7.0 but <9.0 mg/dL). Subjects ingested placebo or IP₆ drinks (600 mg twice daily) during two 2-week intervention periods with a 2-week washout period. The primary outcome was fasting SUA level; the secondary outcome was the urinary uric acid to creatinine ratio. Fasting SUA levels in the IP₆ group were lower than those in the placebo group (p < 0.05). The urinary uric acid to creatinine ratio did not change between the placebo and IP₆ groups (p > 0.05). This study showed that a 2-weeks supplementation period of 600 mg IP₆ twice daily can improve fasting SUA levels in hyperuricemic subjects.

Put "gender glasses" on the effects of phenolic compounds on cardiovascular function and diseases

INTRODUCTION

The influence of sex and gender is particularly relevant in cardiovascular diseases (CVD) as well as in several aspects of drug pharmacodynamics and pharmacokinetics. Anatomical and physiological differences between the sexes may influence the activity of many drugs, including the possibility of their interaction with other drugs, bioactive compounds, foods and beverages. Phenolic compounds could interact with our organism at organ, cellular, and molecular levels triggering a preventive action against chronic diseases, including CVD.

RESULTS

This article will review the role of sex on the activity of these bioactive molecules, considering the existence of sex differences in oxidative stress. It describes the pharmacokinetics of phenolic compounds, their effects on vessels, on cardiovascular system, and during development, including the role of nuclear receptors and microbiota.

CONCLUSIONS

Although there is a large gap between the knowledge of the sex differences in the phenolic compounds' activity and safety, and the urgent need for more research, available data underlie the possibility that plant-derived phenolic compounds could differently influence the health of male and female subjects.

Management of hyperuricemia through dietary polyphenols as a natural medicament: A comprehensive review

Hyperuricemia, a condition due to high serum uric acid level and is notorious to health. It is considered to be a potent risk factor for gout and dramatically associated in the development of many chronic diseases such as malignant tumor, cardiovascular disorders and renal failure. Modern innovative medicinal and therapeutic interventions are underlying these days to combat hyperuricemia. Previously reported studies revealed the significant impact of dietary polyphenols (e.g. anthocyanins, phenolic acids, flavonoids etc.) against hyperurecemia disorder. Dietary plant polyphenols, unlike anti- hyperuricemic agents, are not reported to have any side effects in curing hyperuricemia. The current comprehensive review figure outs the use of dietary polyphenols as a natural remedy for the management of hyperuricemia. The sources, affiliated pathways, mode of actions and factors affecting their efficiency to prevent hyperuricemia are deeply discussed in this article. Additionally, limitations and suggestions regarding previously reported studies are also highlighted.

Mitigating the effects of high fat diet on the brain and behavior with berry supplementation

Berries are rich in bioactive compounds like anthocyanins and show promise for mitigating the effects of high fat diet on the brain and behavior.