Pharmacokinetics of maslinic and oleanolic acids from olive oil – Effects on endothelial function in healthy adults. A randomized, controlled, dose–response study

•First description of maslinic acid bioavailability and pharmacokinetics in humans.•Plasma pentacyclic triterpenes increase directly with their concentration in olive oil.•Bioavailability of maslinic acid in humans is higher than that of oleanolic acid.•First report on in vivo effect of triterpenic acids improving human endothelial function. To date, pharmacokinetics of maslinic (MA) and oleanolic (OA) acids, at normal dietary intakes in humans, have not been evaluated, and data concerning their bioactive effects are scarce. We assessed MA and OA pharmacokinetics after ingestion of olive oils (OOs) with high and low triterpenic acid contents, and specifically the effect of triterpenes on endothelial function. We performed a double-blind, dose–response, randomized, cross-over nutritional intervention in healthy adults, and observed that MA and OA increased in biological fluids in a dose-dependent manner. MA bioavailability was greater than that of OA, and consumption of pentacyclic triterpenes was associated with improved endothelial function. To the best of our knowledge, this is the first time MA pharmacokinetics, and effects on endothelial function in vivo, have been reported in humans.