Dose–response plasma appearance of coffee chlorogenic and phenolic acids in adults

Abstract

This study confirmed previous findings about coffee bioavailability but also showed that coffee phenolics appear in a positive dose-response manner in plasma when drank at nutritionally relevant doses.

The colonic metabolites dihydrocaffeic acid and dihydroferulic acid are more effective inhibitors of in vitro platelet activation than their phenolic precursors

“…55,56 However, these beneficial effects could be limited by their bioavailability which is lower than methylxanthines, with phenolic plasma concentrations lower than 10 µM, depending of the degree of roasting and the consumed dose of coffee. 18,20 The results of this study showed a significant effect of 5-CQA on the modulation of platelet activation at 1 -20 µM, close to concentrations found in plasma after intake of green coffee extract (6 µM). 20 On the contrary, much higher doses of 3,5-DCQA, the other main polyphenol in green coffee and yerba mate, are needed (10 -20 µM) in order to significantly decrease ADP-induced P-selectin expression, much higher than the maximal plasma concentration (2.5 µM) reported for this compound.…”

“…With respect to the metabolites of 5-CQA and 3,5-DCQA, only DHCA showed the ability to significantly modulate platelet activation at 1 µM, the maximal plasma concentration found after coffee intake. 18 We found that the colonic metabolites DHCA and DHFA significantly decreased P-selectin expression in ADP-stimulated platelets at 10 µM, with others showing a trend to decreased Pselectin expression on platelets activated by TRAP after incubation with DHCA. 57 On the contrary, concentrations of at least 100 µM were necessary to inhibit the expression of TRAP-and ADPinduced P-selectin by the early metabolites CA and FA, and 5-CQA, respectively, 42,58 while the 12 results of this study showed a significant decrease of ADP-induced P-selectin expression at noticeably lower concentrations (20, 10 and 1 µM for CA, FA and 5-CQA, respectively), indicating that the colonic metabolites may have an even stronger effect on platelet function than their phenolic precursors.…”

“…CGA are absorbed and metabolized in the stomach, small and large intestine (Figure 2), and their bioavailability depends on the ingested dose. 18 Plasma concentrations of 5-caffeoylquinic acid (5-CQA), the main CGA in green coffee and yerba mate, are low at 6 -30 nM after consumption of roasted coffee, 18,19 and 5.9 µM after consumption of green coffee. 20 In addition, plasma levels of 3,5-dicaffeoylquinic acid (3,5-DCQA) have been reported to be as high as 2.5 µM after the intake of a green coffee extract, 20 although most studies suggested the hydrolysis of 3,5-DCQA to monoacylquinic acid as the main biotransformation pathway.…”

“…20 In addition, plasma levels of 3,5-dicaffeoylquinic acid (3,5-DCQA) have been reported to be as high as 2.5 µM after the intake of a green coffee extract, 20 although most studies suggested the hydrolysis of 3,5-DCQA to monoacylquinic acid as the main biotransformation pathway. 18,19 Caffeic (CA) and ferulic (FA) acids are the main early metabolites,…”

Impact of dose on the bioavailability of coffee chlorogenic acids in humans

“…7,8 The low nM levels of CQAs and FQAs in plasma is also supported by other studies which have involved enzymic deglucuronidation and desulfation of the plasma samples. 9 The aim of the current study was to expand the earlier work of Stalmach et al 7,8 and to investigate the impact on the plasma pharmacokinetic profiles and urinary excretion of chlorogenic acid-derived metabolites after the acute ingestion by human volunteers of three instant coffees containing 412, 635 and 795 mol of chlorogenic acids per 200 mL serving.…”