Mass spectrometry imaging to evaluate (poly)phenol distribution in animal tissues

(Poly)phenols are plant-derived compounds with potential benefits for human health. Understanding the absorption and distribution of phenolic compounds within the human body is of great importance for identifying their bioactive form in target organs or tissues, and, consequently, for understanding their biological effects. Mass spectrometry imaging (MSI) is an analytical method that provides a visual in situ representation of the molecular distribution within complex samples and biological tissues. This technique allows to map various molecules in a tissue, providing spatial information that cannot be obtained through traditional mass spectrometry analytical approaches. This review aims to provide a valuable and informative summary of the published MSI applications for evaluating (poly)phenol absorption and distribution in animal tissues. Following PRISMA guidelines, the search string was launched in two web databases, Web of Science and Scopus. Of the nine reviewed studies, one applied desorption electrospray ionization (DESI) and the rest matrix-assisted laser desorption ionization (MALDI) to visualize (poly)phenol distribution in mice or rats. MSI represents a viable approach for exploring the absorption and distribution of these bioactive compounds in tissues, useful to enhance the comprehension of their pharmacokinetics, along with their possible site of action and transport mechanisms implicated in their distribution. The findings indicate that the application of MSI to study phenolic compounds in vivo is currently limited, but it is expected to increase as researchers seek to advance their comprehension of the health-promoting attributes of (poly)phenols and their metabolites.