Interactions of trace element profiles with Nrf2 signaling in mice

Project Summary

We hypothesize that age-specific trace element (TE) profiles are modulating the activity of the redox-sensitive transcription factor Nrf2. Vice versa, Nrf2 is supposed to regulate the systemic TE status by changing the expression of TE transport and binding proteins, e.g., in the intestine. To address these points we aim to conduct feeding experiments in young and old mice fed with adequate or suboptimal amounts of six essential TE, including Cu, Fe, I, Mn, Se, and Zn. In addition, we will establish ‘young-adapted’ and ‘old-adapted’ TE diets, which will mimic the TE status of young and old human EPIC participants. A great advantage over human studies is the availability of murine tissue samples, in which effects of different TE diets will be studied in close collaboration with all experimental groups of the Research Unit. We will focus on the liver and the intestine. Using these tissues we will correlate TE profiles, TE biomarkers, TE-specific binding proteins, and aging markers with Nrf2 pathway activity. We aim to identify new Nrf2-dependent genes relevant for TE homeostasis and intestinal TE absorp­tion both in young and old mice. To identify the Nrf2-modulated part of TE effects, Nrf2 knockout (KO) mice will be studied in parallel. Potential differences between young and old WT and Nrf2-KO mice may provide an explanation for age-specific TE profiles.