The Influence of Tart Cherry (Prunus cerasus, cv Montmorency) Concentrate Supplementation for 3 Months on Cardiometabolic Risk Factors in Middle-Aged Adults: A Randomised, Placebo-Controlled Trial

Anthocyanins in Vascular Health and Disease: Mechanisms of Action and Therapeutic Potential

ABSTRACT

Unhealthy lifestyles have placed a significant burden on individuals' cardiovascular health. Anthocyanins are water-soluble flavonoid pigments found in a wide array of common foods and fruits. Anthocyanins have the potential to contribute to the prevention and treatment of cardiovascular disease by improving lipid profiles and vascular function, reducing blood glucose levels and blood pressure, and inhibiting inflammation. These actions have been demonstrated in numerous clinical and preclinical studies. At the cellular and molecular level, anthocyanins and their metabolites could protect endothelial cells from senescence, apoptosis, and inflammation by activating the phosphoinositide 3-kinase/protein kinase B/endothelial nitric oxide synthases, silent information regulator 1 (SIRT1), or nuclear factor erythroid2-related factor 2 pathways and inhibiting the nuclear factor kappa B, Bax, or P38 mitogen-activated protein kinase pathways. Furthermore, anthocyanins prevent vascular smooth muscle cell from platelet-derived growth factor -induced or tumor necrosis factor-α-induced proliferation and migration by inhibiting the focal adhesion kinase and extracellular regulated protein kinases signaling pathways. Anthocyanins could also attenuate vascular inflammation by reducing the formation of oxidized lipids, preventing leukocyte adhesion and infiltration of the vessel wall, and macrophage phagocytosis of deposited lipids through reducing the expression of cluster of differentiation 36 and increasing the expression of ATP-binding cassette subfamily A member 1 and ATP-binding cassette subfamily G member 1. At the same time, anthocyanins could lower the risk of thrombosis by inhibiting platelet activation and aggregation through down-regulating P-selectin, transforming growth factor-1, and CD40L. Thus, the development of anthocyanin-based supplements or derivative drugs could provide new therapeutic approaches to the prevention and treatment of vascular diseases.

Phenolic Compounds from Cherries and Berries for Chronic Disease Management and Cardiovascular Risk Reduction

Cardiovascular diseases (CVDs) are a leading cause of mortality worldwide. Therefore, there is increasing interest in dietary interventions to reduce risk factors associated with these conditions. Cherries and berries are rich sources of bioactive compounds and have attracted attention for their potential cardiovascular benefits. This review summarises the current research on the effects of cherry and berry consumption on cardiovascular health, including in vivo studies and clinical trials. These red fruits are rich in phenolic compounds, such as anthocyanins and flavonoids, which have multiple bioactive properties. These properties include antioxidant, anti-inflammatory, and vasodilatory effects. Studies suggest that regular consumption of these fruits may reduce inflammation and oxidative stress, leading to lower blood pressure, improved lipid profiles, and enhanced endothelial function. However, interpreting findings and establishing optimal dosages is a challenge due to the variability in fruit composition, processing methods, and study design. Despite these limitations, the evidence highlights the potential of cherries and berries as components of preventive strategies against CVD. Further research is needed to maximise their health benefits and improve clinical practice.

Dose-dependent effect of tart cherry on selected cardiometabolic risk factors: A GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials

AIMS

This study aimed to clarify the effectiveness of tart cherries on anthropometric, lipid, and glycemic indices. We also aimed to clarify the appropriate dosage for this effect and suggest directions for future studies.

METHODS

PubMed, Scopus, and Web of Science were searched until May 2022. Twelve eligible trials were included. The pooled results were reported as weighted mean differences (WMD) and 95 % confidence intervals (CIs). The Cochrane risk of bias and GRADE tools were used to assess the risk of bias and certainty of the evidence, respectively.

RESULTS

Tart cherry generally showed no significant effects on cardiometabolic risk factors. But subgroup analysis revealed that tart cherry significantly lowered total cholesterol (WMD: -0.33 mmol/l; 95 % CI: -0.55, -0.10), triglyceride (WMD: -0.19 mmol/l; 95 % CI: -0.26, -0.12), and low-density lipoprotein cholesterol (WMD: -0.36 mmol/l; 95 % CI: -0.58, -0.14), in unhealthy populations. Additionally, subgroup analysis indicated that the favorable effects of tart cherry were more pronounced in a single dose, longer duration, elderly, and obese individuals. Dose-response analysis revealed that 20 ml concentrate has the greatest effect in reducing total cholesterol (WMD: -0.40 mmol/l; 95 % CI: -0.61, -0.19), triglyceride (WMD: -0.23 mmol/l; 95 % CI: -0.33, -0.13), and elevating high-density lipoprotein cholesterol (WMD: 0.20 mmol/l; 95 % CI: 0.17, 0.22).

CONCLUSIONS

Tart cherry supplementation did not have significant effects on anthropometric and glycemic indices, but can improve lipid profile, especially in a single dose, longer duration, and in elderly, obese, and unhealthy individuals.

Anthocyanin Effects on Vascular and Endothelial Health: Evidence from Clinical Trials and Role of Gut Microbiota Metabolites

Hypertension and derived cardiovascular disease (CVD) are among the leading causes of death worldwide. Increased oxidative stress and inflammatory state are involved in different alterations in endothelial functions that contribute to the onset of CVD. Polyphenols, and in particular anthocyanins, have aroused great interest for their antioxidant effects and their cardioprotective role. However, anthocyanins are rarely detected in blood serum because they are primarily metabolized by the gut microbiota. This review presents studies published to date that report the main results from clinical studies on the cardioprotective effects of anthocyanins and the role of the gut microbiota in the metabolism and bioavailability of anthocyanins and their influence on the composition of the microbiota. Even if it seems that anthocyanins have a significant effect on vascular health, more studies are required to better clarify which molecules and doses show vascular benefits without forgetting the crucial role of the microbiota.

Health Benefits of Montmorency Tart Cherry Juice Supplementation in Adults with Mild to Moderate Ulcerative Colitis: A Protocol for a Placebo Randomized Controlled Trial

Ulcerative colitis, characterized by its relapsing and remissive nature, negatively affects perception, body image, and overall quality of life. The associated financial burden underscores the need for alternative treatment approaches with fewer side effects, alongside pharmaceutical interventions. Montmorency tart cherries, rich in anthocyanins, have emerged as a potential natural anti-inflammatory agent for ulcerative colitis. This manuscript outlines the study protocol for a randomized placebo-controlled trial investigating the effects of Montmorency tart cherry in individuals with ulcerative colitis. The trial aims to recruit 40 participants with mild to moderate disease activity randomly assign them to either a Montmorency tart cherry or placebo group. The intervention will span 6 weeks, with baseline and 6-week assessments. The primary outcome measure is the Inflammatory Bowel Disease Quality of Life Questionnaire. Secondary outcomes include other health-related questionnaires and biological indices. Statistical analysis will adhere to an intention-to-treat approach using linear mixed effect models. Ethical approval has been obtained from the University of Hertfordshire (cLMS/SF/UH/05240), and the trial has been registered as a clinical trial (NCT05486507). The trial findings will be disseminated through a peer-reviewed publication in a scientific journal.

Does anthocyanins consumption affect weight and body composition? A systematic review and meta-analysis of randomized controlled trials

Background and Aims

Anthocyanins (ACNs) are water-soluble plant pigments belong to flavonoids with beneficial effects on health and disease prevention. Some studies have examined the effect of ACNs on anthropometric and body composition indices, but the findings were inconsistent. This systematic review and meta-analysis aimed to investigate the effect of ACNs and sources rich in anthocyanins on body mass index (BMI), body weight (BW), waist circumference (WC), hip circumference (HC), waist-hip ratio (WHR), percentage of fat mass (PFM) and fat free mass (FFM).

Methods

PubMed, Web of Science, Scopus, and Google Scholar were searched with no limitation until May 2021 to find relevant randomized controlled clinical trials (RCT). The risk of bias was assessed utilizing Cochrane collaboration's tool. Weighted mean differences (WMD) and 95% confidence intervals (CIs) were obtained using a random effects model.

Results

A total of 31 RCTs (with 0.77-640 mg/day of ACNs supplementation for 28-90 days) with 1438 participants were included. No significant effect was found in BMI, WC, HC, WHR, PFM and FFM after ACNs consumption.

Conclusions

The results showed that ACNs did not significantly affect anthropometric and body composition parameters. Further high-quality RCTs are required to validate these findings.

Effect of Tart Cherry Juice Consumption on Body Composition and Anthropometric Measures: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

The present systematic review and meta-analysis were accomplished to understand the effects of tart cherry juice consumption on body composition and anthropometric measures. Five databases were searched using relevant keywords from inception to January 2022. All clinical trials investigating the effect of tart cherry juice consumption on body weight (BW), body mass index (BMI), waist circumference (WC), fat mass (FM), fat-free mass (FFM), and percentage body fat (PBF) were included. Out of 441 citations, 6 trials that enrolled 126 subjects were included. Tart cherry juice consumption significantly did not reduce BW (weighted mean difference [WMD], -0.4 kg; 95% confidence interval [CI], -3.25 to 2.46; p = 0.789; GRADE = low), BMI (WMD, -0.07 kg/m²; 95% CI, -0.89 to 0.74; p = 0.857; GRADE = low), FM (WMD, 0.21 kg; 95% CI, -1.83 to 2.25; p = 0.837; GRADE = low), FFM (WMD, -0.12 kg; 95% CI, -2.47 to 2.27; p = 0.919; GRADE = low), WC (WMD, 1.69 cm; 95% CI, -1.88 to 5.27; p = 0.353; GRADE = low), and PBF (WMD, 0.18%; 95% CI, -1.81 to -2.17; p = 0.858; GRADE = low). Overall, these data suggest that tart cherry juice consumption has no significant effect on BW, BMI, FM, FFM, WC, and PBF.

Dark Sweet Cherry (Prunus avium) Supplementation Reduced Blood Pressure and Pro-Inflammatory Interferon Gamma (IFNγ) in Obese Adults without Affecting Lipid Profile, Glucose Levels and Liver Enzymes

Dark sweet cherries (DSC) are rich in fiber and polyphenols that decrease risk factors associated with obesity. This single-blind randomized placebo-controlled study investigated DSC effects on inflammation, cardiometabolic, and liver health biomarkers in obese adults. Participants (>18 years, body mass index (BMI) = 30-40 kg/m²) consumed 200 mL of DSC drink (juice supplemented with DSC powder) (n = 19) or a placebo drink (n = 21) twice/day for 30 days. Anthropometric and physiological biomarkers were monitored at baseline (D1), mid-point (D15), and endpoint (D30) visits. Blood inflammatory biomarkers were assessed at D1, D15, and D30, and blood lipids, glucose, and liver enzymes at D1 and D30. DSC consumption lowered systolic blood pressure (SBP) (p = 0.05) and decreased diastolic blood pressure (DBP) compared to placebo (p = 0.04). Stratification of participants by BMI revealed a greater (p = 0.008) SBP reduction in BMI > 35 participants. DSC lowered pro-inflammatory interferon-gamma (IFNγ) (p = 0.001), which correlated with SBP changes. The interleukin (IL)-1RA and SBP changes were correlated in the placebo group, as well as triglycerides (TG) with DBP. The increased IL-10 levels in the placebo group suggested a compensatory mechanism to counteract elevated IFNγ levels. No significant between-group differences were detected for blood lipids, glucose, and liver enzymes. In conclusion, DSC helped to decrease blood pressure levels and inflammation in obese adults.

Effects of tart cherry juice consumption on cardio-metabolic risk factors: A systematic review and meta-analysis of randomized-controlled trials

BACKGROUND

Tart cherries are rich in bioactive compounds, such as anthocyanins and other phytochemicals known to have antioxidant properties and exert cardiovascular protective effects. However, there is no definitive consensus on this context. The present systematic review and meta-analysis aimed to investigate the effect of tart cherry juice consumption on cardio-metabolic risk factors.

METHODS

A systematic search was conducted on electronic databases, including PubMed, Web of Science, Scopus, and Google Scholar from inception up to December 2021 to identify eligible RCT studies. A random-effect model was utilized to estimate the weighted mean difference (WMD) and 95% confidence (95% CI).

RESULTS

Ten RCTs were included in the present meta-analysis. The pooled analysis revealed that tart cherry juice consumption led to a significant reduction in the fasting blood sugar (FBS) levels (WMD = -0.51 mg/dl [95% CI: -0.98, -0.06]). This lowering effect of FBS was robust in subgroups with cross-over studies, participants with age range ≥ 40, duration of follow-up ≤ 4 weeks, and baseline BMI ≥ 30. In contrast, tart cherry juice had no effect on total cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), insulin, body mass index (BMI), fat mass, systolic and diastolic blood pressure. However, in the subgroup analysis, some significant effects were observed for insulin, TG, TC, LDL-C, and HDL-C.

CONCLUSION

In summary, this meta-analysis showed that tart cherry juice mostly had a favorable effect on FBG levels. However, further RCTs with long-term intervention with different doses of administration are needed.

The Role of Berry Consumption on Blood Pressure Regulation and Hypertension: An Overview of the Clinical Evidence

The existence of a relationship between the consumption of dietary berries and blood pressure reduction in humans has been repeatedly hypothesized and documented by an increasing body of epidemiological and clinical evidence that has accumulated in recent years. However, results are mixed and complicated by a number of potentially confounding factors. The objective of this article is to review and summarize the available clinical evidence examining the effects of berry consumption on blood pressure regulation as well as the prevention or treatment of hypertension in humans, providing an overview of the potential contribution of distinctive berry polyphenols (anthocyanins, condensed tannins and ellagic acid), and results of dietary interventions with blueberries, bilberries, cranberries, raspberries, strawberries, chokeberries, cherries, blackcurrants and açai berries. We conclude that, while there is insufficient evidence supporting the existence of a direct blood pressure lowering effect, there is stronger evidence for specific types of berries acting indirectly to normalize blood pressure in subjects that are already hypertensive.

The beneficial effect of tart cherry on plasma levels of inflammatory mediators (not recovery after exercise): A systematic review and meta-analysis on randomized clinical trials

BACKGROUND

Chronic inflammation has been classified as one of the most important threats to health. Scientists suggested that tart cherry (TC) can reduce plasma levels of inflammatory mediators. Therefore, the aim of this study was to summarize the effect of TC on circulating C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) among adult participants in non-exercise randomized clinical trials (RCTs).

METHODS AND MATERIALS

The eligible English-language RCTs were found by searching databases including PubMed, Web of Science, Cochrane Library, Scopus, and clinical Trials.gov up to May 2022, with no time limit. We used the mean change from baseline and its standard deviation for both intervention and comparison groups to calculate the effect size. The random-effects model proposed by DerSimonian and Laird was used to estimate the overall summary effect and the heterogeneity. We used PRISMA 2020 guidelines to report this study.

RESULTS

Ten RCTs were included in this study. The results demonstrated that TC had a significant decreasing effect on plasma CRP level compared with the comparison group (weighted mean differences (WMD) = -0.55 mg/L; 95% confidence interval (CI): - 1.03, - 0.06; p = 0.029), but had no significant effect on plasma IL-6 compared with comparison group (WMD = 0.08 pg/mL; 95% CI: -0.02, 0.17; p = 0.10). The effect of TC consumption on plasma TNF-α level was evaluated in only three studies that showed no significant effects (p>0.05).

CONCLUSION

Our results confirmed a significant decreasing effect of TC on CRP. Regarding IL-6 and TNF-α, our study did not present any significant effect of TC.

Effects of Montmorency Tart Cherry and Blueberry Juice on Cardiometabolic and Other Health-Related Outcomes: A Three-Arm Placebo Randomized Controlled Trial

The current study aimed to investigate the influence of tart cherry and blueberry juices on cardiometabolic and other health indices following a 20-day supplementation period. Forty-five adults were randomly assigned to receive tart cherry, blueberry, or a placebo, of which they drank 60 mL per day for 20 days. The primary outcome, which was systolic blood pressure, and secondary measures, including anthropometric, energy expenditure, substrate oxidation, hematological, diastolic blood pressure/resting heart rate, psychological wellbeing, and sleep efficacy, were measured before and after the intervention. There were no statistically significant differences (p > 0.05) for systolic blood pressure; however, total and LDL cholesterol were significantly improved with blueberry intake (pre: total cholesterol = 4.36 mmol/L and LDL cholesterol = 2.71 mmol/L; post: total cholesterol = 3.79 mmol/L and LDL cholesterol = 2.23 mmol/L) compared to placebo (pre: total cholesterol = 4.01 mmol/L and LDL cholesterol = 2.45 mmol/L; post: total cholesterol = 4.34 mmol/L and LDL cholesterol = 2.67 mmol/L). Furthermore, psychological wellbeing indices measured using the Beck Depression Inventory, State Trait Anxiety Inventory, and COOP WONCA improved statistically in the blueberry arm compared to placebo. Given the clear association between lipid concentrations and the risk of cardiovascular disease as well as the importance of psychological wellbeing to health-related quality of life, this investigation indicates that it could be an effective approach to assist in managing cardiometabolic disease.

Anthocyanin-Rich Supplementation: Emerging Evidence of Strong Potential for Sport and Exercise Nutrition

Dark-colored fruits, especially berries, have abundant presence of the polyphenol anthocyanin which have been show to provide health benefits. Studies with the berry blackcurrant have provided notable observations with application for athletes and physically active individuals. Alterations in exercise-induced substrate oxidation, exercise performance of repeated high-intensity running and cycling time-trial and cardiovascular function at rest and during exercise were observed with intake of New Zealand blackcurrant. The dynamic plasma bioavailability of the blackcurrant anthocyanins and the anthocyanin-derived metabolites must have changed cell function to provide meaningful in-vivo physiological effects. This perspective will reflect on the research studies for obtaining the applied in-vivo effects by intake of anthocyanin-rich supplementation, the issue of individual responses, and the emerging strong potential of anthocyanins for sport and exercise nutrition. Future work with repeated intake of known amount and type of anthocyanins, gut microbiota handling of anthocyanins, and coinciding measurements of plasma anthocyanin and anthocyanin-derived metabolites and in-vivo cell function will be required to inform our understanding for the unique potential of anthocyanins as a nutritional ergogenic aid for delivering meaningful effects for a wide range of athletes and physically active individuals.

Polyphenol-rich tart cherries (Prunus Cerasus, cv Montmorency) improve sustained attention, feelings of alertness and mental fatigue and influence the plasma metabolome in middle-aged adults: a randomised, placebo-controlled trial

Tart Montmorency cherries (MC) are a particularly rich source of anthocyanins and other polyphenols that have been shown to elicit antioxidant, anti-inflammatory and vasomodulatory actions. The current study aimed to determine the influence of chronic MC supplementation on cognitive function and mood. In a 3-month double-blinded, placebo-controlled parallel study, middle-aged adults (mean ± sd: 48 ± 6 years) were randomly assigned to either 30 ml twice daily of MC (n 25) or the same amount of an isoenergetic placebo (n 25). Cognitive function and mood were assessed before and after supplementation using a computerised cognitive task battery and visual analogue scales. Cerebral blood flow was also monitored by near-infrared spectroscopy during the task battery, and questionnaires were administered to determine subjective sleep and health status and plasma metabolomics were analysed before and after supplementation. After 3 months, the MC resulted in higher accuracy in digit vigilance (mean difference: 3·3, 95 % CI: 0·2, 6·4 %) with lower number of false alarms (mean difference: -1·2, 95 % CI: -2·0, -0·4) compared with the placebo. There was also a treatment effect for higher alertness (mean difference: 5·9, 95 % CI: 1·3, 10·5 %) and lower mental fatigue ratings (mean difference -9·5, 95 % CI: -16·5, -2·5 %) with MC. Plasma metabolomics revealed an increase in a number of amino acids in response to MC intake, but not placebo. These data suggest an anti-fatiguing effect of MC supplementation as well as the ability to improve sustained attention during times of high cognitive demand, this could be related to changes in amino acid metabolism.

Thirty Days of Montmorency Tart Cherry Supplementation Has No Effect on Gut Microbiome Composition, Inflammation, or Glycemic Control in Healthy Adults

Tart cherries possess properties that may reduce inflammation and improve glycemic control, however human data on supplementation and the gut microbiota is equivocal. Processing (i.e., juice concentrate, dried, frozen) may affect the properties of tart cherries, and therefore alter their efficacious health benefits. Therefore, the purpose of this study was to investigate the effect of 30 days of supplementation with Montmorency tart cherry (MTC) in concentrate or freeze-dried form on the gut microbiome and markers of inflammation and glycemic control. Healthy participants with no known disease (n = 58, age: 28 ± 10 y, height: 169.76 ± 8.55 cm, body mass: 72.2 ± 12.9 kg) were randomly allocated to four groups and consumed either concentrate or freeze-dried capsules or their corresponding placebos for 30 days. Venous blood samples were drawn at baseline, day 7, 14, and 30 and analyzed for inflammatory markers TNF-alpha, uric acid, C-reactive protein, and erythrocyte sedimentation rate and glycemic control markers glycated albumin, glucose and insulin. A fecal sample was provided at baseline, day 14 and 30 for microbiome analysis. TNF-alpha was significantly lower at 30 vs. 14 days (p = 0.01), however there was no other significant change in the inflammatory markers. Insulin was not changed over time (p = 0.16) or between groups (p = 0.24), nor was glycated albumin different over time (p = 0.08) or between groups (p = 0.56), however glucose levels increased (p < 0.001) from baseline (4.79 ± 1.00 mmol·L^-1) to 14 days (5.21 ± 1.02 mmol·L^-1) and 30 days (5.61 ± 1.22 mmol·L^-1) but this was no different between groups (p = 0.33). There was no significant change in composition of bacterial phyla, families, or subfamilies for the duration of this study nor was there a change in species richness. These data suggest that 30 days of MTC supplementation does not modulate the gut microbiome, inflammation, or improve glycemic control in a healthy, diverse group of adults. Clinical Trail Registration:https://clinicaltrials.gov/ct2/show/NCT04467372, identifier: NCT04467372.

Effects of Montmorency Tart Cherry and Blueberry Juice on Cardiometabolic Outcomes in Healthy Individuals: Protocol for a 3-Arm Placebo Randomized Controlled Trial

Cardiometabolic disease is recognized as the predominant cause of global mortality and healthcare expenditure. Whilst pharmaceutical interventions are effective in the short term, their long-term efficacy remain equivocal and their associated side-effects are concerning. Owing to their high levels of anthocyanins, Montmorency tart cherries and blueberries have been cited as potentially important natural treatment/preventative modalities for cardiometabolic disease. This study proposed a randomized controlled trial, aims to test the effects of consumption of Montmorency tart cherry and blueberry juice on cardiometabolic outcomes compared to placebo. This 20-day, parallel, single-blind, randomized, placebo-controlled trial will recruit 45 individuals, who will be assigned to receive 60 mL per day of either Montmorency tart cherry juice, blueberry juice or a cherry/blueberry flavoured placebo. The primary study outcome is the between-group difference in systolic blood pressure from baseline to post-intervention. Secondary outcome measures will be between-group differences in anthropometric, energy expenditure and substrate oxidation (during rest and physical activity), haematological, blood pressure/resting heart rate, psychological wellbeing and sleep efficacy indices. Statistical analysis will be conducted on an intention-to-treat basis. This study has been granted ethical approval by the University of Central Lancashire, Health Research Ethics Committee (ref: HEALTH 0016) and formally registered as a trial. Dissemination of the study findings from this investigation will be through publication in a leading peer-reviewed journal.