AHR and persistent truncus arteriosus: Supplementation of SCFAs and Lactobacillus-based probiotics have indeed been demonstrated to have cardioprotective effects,14 and tryptophan supplementation deemed to be anti-inflammatory in other experimental models of chronic inflammation.37,38 Our results indicating that the SCFA receptor GPR43 and the AhR are both decreased in the heart in response to TAC further support a protective role for these metabolites.