**Author details**

of these phytochemicals to interact with multiple biomolecules, including proteins, biomembrane lipids, and endotoxins. Bioactivity of PACs is highly structuredependent and enriched botanical extracts composed by a large variety of molecular structures exert a wide range of unrelated physiological effects. In this way, PACrich extracts can modulate kinase activity, several signal transduction pathways implicated in the inflammatory response and the remodeling of TJs. Flavan-3-ol monomers and short PAC oligomers are absorbed by enterocytes and immune cells and exert a direct action on kinases and transcription factors. Bioactivity of larger oligomers and polymeric PACs do not require direct intestinal absorption and are able to bind protein receptors on the enterocyte and immune cell surfaces as well as luminal bacterial endotoxins, thus inhibiting pro-inflammatory signaling and improving barrier integrity. Due to the negligible absorption of large PAC molecules in the small intestine, phenyl-γ-valerolactones and phenolic acids produced by the microbiota metabolism in the colon are thought to play an important role in these

The barrier-protective properties of PACs are emerging as a potential adjunctive support to current therapies for managing obesity related intestinal dysfunction and IBD. However, there have been no large, well-designed clinical trials establishing the efficacy of these phytochemicals in chronic conditions. At preclinical stages, the use of animal models is the predominant approach for testing novel therapies for intestinal dysfunction, although several strategies for replacing animal experiments have been proposed. As there are still no studies on the impact of PACs on human intestinal health, ex vivo models of the human intestine could be a more physiologically reliable alternative to human cell lines and an alternative to animal experi-

C. González-Quilen has received financial support through a FI-AGAUR grant from the Generalitat de Catalunya. M. Pinent and X. Terra are Serra-Húnter fellows

This work was funded by the Spanish Ministerio de Economía y Competitividad

health-promoting effects, and thus need to be further researched.

mentation in preclinical development.

at the Universitat Rovira i Virgili, Tarragona, Spain.

The authors declare no conflict of interest.

**Acknowledgements**

*Weight Management*

**Conflicts of interest**

(Grant: AGL2017-83477-R).

**Funding**

**284**

Carlos González-Quilen, Esther Rodríguez-Gallego, Raúl Beltrán-Debón, Montserrat Pinent, Anna Ardévol, Maria Teresa Blay and Ximena Terra\* MoBioFood Research Group, Departament de Bioquímica i Biotecnologia, Universitat Rovira i Virgili, Tarragona, Spain

\*Address all correspondence to: ximena.terra@urv.cat

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
