Plasma-Induced Changes in the Metabolome Following Polyphenol Consumption

Participants Twelve healthy participants (nine male and three female) were recruited for this study; the mean ± SD age, stature, mass and body mass index (BMI) were 29 ± 7 years old, 174.8 ± 9.3 cm, 77.29 ± 10.52 kg and 25.23 ± 1.87 kg/m2, respectively. All participants were healthy, as assessed by a health-screening questionnaire and provided written, informed consent. Exclusion criteria for the study were as follows: food allergy (as discussed with research team), history of gastrointestinal, renal, cardiovascular or thyroid disease and current use of any food supplementations. This study received ethical approval from Northumbria University Ethics Committee (reference number: 39904) (clinical trial tbc).

Experimental Design The study utilised a double blind, three-arm cross-over, pseudo-randomised (counter-balanced to eliminate order effects) design in order to identify metabolomic shifts following the acute ingestion of a low dose (LOW), high dose (HI) of TC or placebo (CON). A washout period of at least 7 days (but not greater than 21 days) between each phase was implemented. Participants were required to attend the start of each phase of the study at 7:45 am following a 10 h overnight fast in order to account for diurnal variation (Figure 1). Upon arrival to the lab, the participants baseline blood pressure (BP) was recorded in a rested state (following at least 5 mins of sitting), then cannulated for serial blood sampling. A standardized breakfast was then provided. Subsequent measures were then taken at baseline, 1, 2, 3, 5 and 8 hrs post-VTC consumption. Water was provided ad-libitum, but no additional food was given during testing visits.

Treatments and Dietary Control The low (LOW) and high (HI) dose consisted of 3 or 6 g of the TC supplement (CherryCraft), respectively, or a 3g capsule placebo (CON) matched for caloric content using maltodextrin. The low TC dose provided approximately 60-78 mg of anthocyanins, 8.07 kcal and had a macronutrient content of 1.215 g, 0.003 g, 0.042 g, for carbohydrates, fat and protein, respectively. The high TC dose provided approximately 120-156 mg of anthocyanins, 16.14 kcal with 2.43 g, 0.006 g, 0.08 g for carbohydrates, fat and protein, respectively.

Participants were requested to follow their habitual diet throughout the trial. Food diaries were completed for the 24 hrs before each testing visit to replicate (as close to) prior to testing on following testing visits. The standardized breakfast consisted of white toast (2 slices of Sainsbury's medium white bread) and butter (approx. 16g of Bertolli/Vitalite (a vegan alternative, matched as closely as possible for calories and macronutrient content)). Participants were given water to drink ad-libitum throughout the testing visits, this was measured and refilled from baseline, and 1, 2, 3, 5 and 8 hrs post breakfast and supplement ingestion.

Blood Pressure Monitoring Blood pressure was monitored throughout the testing visits, immediately upon arrival to the lab and, 1, 2, 3, 5 and 8 hrs following ingestion of the supplement.