A battery of translational biomarkers for the assessment of the in vitro and in vivo antioxidant action of plant polyphenolic compounds: The biomarker issue

Abstract

Over the last decades, the scientific findings stressing the beneficial health implications of plant-derived compounds (i.e., plant extracts rich in polyphenols) have been increased significantly. Assessing the properties of such compounds throughout the redox continuum is a common practice for the evaluation of their dynamics in reinforcing the antioxidant and antitoxic defence of tissues and, even, whole organisms or in the refinement of free radical-related disease onset. In the present contribution we propose a battery of translational biomarkers for measuring the antioxidant, antimutagenic and antitoxic capacities of plant compounds in three levels. The level 1 is the characterization of plant-derived compounds in vitro by detecting their antiradical and reducing capacity and their antimutagenic and anticarcinogenic properties. In the level 2, the tested agents should be administered in diverse cell lines in order to be examined for their antitoxic and antioxidant capacities. Although cell lines are considered as an in vitro system, it is undisputable that they are an in vivo-like environment and, thus, a link to in vivo settings. The level 3 is the administration of plant compounds in vivo, in experimental animals or humans either individually or as food supplements. The biomarkers for oxidative damage, antioxidant capacity and reducing/oxidative potential analyzed here seem to be suitable surrogate endpoints in the effort to extrapolate in vitro evidence to in vivo models. It is recommended that the aforementioned three lines of research (i.e., in vitro, cell culture environment and in vivo) should be applied in order to holistically reveal the biological action of plant polyphenolic compounds in the frame of redox biology and toxicology. © 2018 Elsevier B.V.