Anthocyanins attenuate vascular and inflammatory responses to a high fat high energy meal challenge in overweight older adults: A cross-over, randomized, double-blind clinical trial.

BACKGROUND & AIMS: Postprandial metabolic imbalances are important indicators of later developing cardiovascular disease (CVD). This study investigated the effects of food anthocyanins on vascular and microvascular function, and CVD associated biomarkers following a high fat high energy (HFHE) meal challenge in overweight older adults. METHODS: Sixteen subjects (13 female, 3 male, mean age 65.9 SD 6.0 and body mass index 30.6 kg/m2 SD 3.9) participated in a crossover, randomized, controlled, double-blind clinical trial (registered under Australian New Zealand Clinical Trials Registry, identifier no. ACTRN12620000437965). Participants consumed a HFHE meal with a 250 mL dose of either intervention (anthocyanins-rich Queen Garnet Plum) or control (apricot) juice. Blood samples and blood pressure measures were collected at baseline, 2 h and 4 h following the HFHE meal. Vascular and microvascular function were evaluated at baseline and 2 h after the HFHE meal. RESULTS: Participants had a higher 2 h postprandial flow-mediated dilatation (+1.14%) and a higher microvascular post-occlusive reactive hyperaemia (+0.10 perfusion units per mmHg) when allocated to the anthocyanin compared to the control arm (P = 0.019 and P = 0.049, respectively). C-reactive protein was lower 4 h postprandially in the anthocyanins (1.80 mg/L, IQR 0.90) vs control arm (2.30 mg/L, IQR 1.95) (P = 0.026), accompanied by a trend for lower concentrations of interleukin-6 (P = 0.075). No significant postprandial differences were observed between treatments for blood pressure, triacylglycerol, total cholesterol, serum derivatives of reactive oxidative metabolites, tumor necrosis factor alpha, interleukin-1 beta, or maximum microvascular perfusion following iontophoresis of acetylcholine. CONCLUSION: Fruit-based anthocyanins attenuated the potential postprandial detrimental effects of a HFHE challenge on parameters of vascular and microvascular function, and inflammatory biomarkers in overweight older adults. Anthocyanins may reduce cardiovascular risk associated with endothelial dysfunction and inflammatory responses to a typical high fat 'Western' meal. Further studies are required to better elucidate the clinical implications of postprandial biomarkers of CVD.

The Postprandial Effect of Anthocyanins on Cardiovascular Disease Risk Factors: a Systematic Literature Review of High-Fat Meal Challenge Studies.

PURPOSE OF REVIEW: Recurrent post-prandial metabolic imbalances are important contributing factors to the development of cardiovascular disease (CVD). This study evaluated whether anthocyanin consumption attenuates the deleterious postprandial response of high-fat meals on CVD risk factors including blood pressure, vascular endothelial function, lipid profile and biomarkers related to oxidative stress, antioxidant status and immune response. RECENT FINDINGS: Five electronic databases were searched up to the period of 1 February 2020, yielding 13 eligible studies, including randomised or cross-over clinical trials (18-59 years of age), using PRISMA guidelines (PROSPERO registration: CRD42019126265). Potential bias was assessed using the revised Cochrane risk-of-bias tool for randomised trials. Beneficial effects of anthocyanins were reported in biomarkers of oxidative stress and antioxidant status in 6 out of 9 studies, and in 3 out of 6 studies for inflammatory response. Two positive results were found concerning attenuation of post-prandial endothelial dysfunction, increased triacylglycerol and total cholesterol exerted by the high fat meal. Blood pressure and lipoproteins were the parameters with least beneficial results. Our systematic literature review revealed beneficial effects of dietary anthocyanin interventions on CVD risk factors following a HFM challenge; however, heterogeneity in results exists. The most promising results were for the attenuation of deleterious postprandial effects on oxidative stress and antioxidant status, triacylglycerol and total cholesterol concentrations, vascular endothelial function and inflammatory biomarkers. Post-prandial changes in blood pressure and lipoproteins were least affected by anthocyanins. Further studies are required in order to better elucidate the post-prandial effects of anthocyanins and CVD risk factors.