This 2020 rodent study investigated effects of broccoli sprout hydrolysis compound indole-3-carbinol:

“I3C metabolites act as ligands of the aryl hydrocarbon receptor (AhR), an important sensor for environmental polyaromatic chemicals. We investigated how dietary AhR ligand supplementation influences AhR target gene expression and intestinal microbiota composition.

Environmental signals, such as dietary, microbial, or xenobiotic factors, are sensed in intestinal tissue AhR, an important regulator of metabolism. It influences immune cell homeostasis and immune activation in the intestine.

AhR activation plays an important role in intestinal immunity, contributing to intestinal homeostasis, inflammation, and host defense:

• AhR activation through high affinity AhR ligands has been shown to stimulate production of antimicrobial peptides.
• AhR has been shown to be an important regulator of T cell immunity.

This indicates a major role of AhR in resolving intestinal inflammation.

High fat diet and control diet lead to reduced expression of Ahrr in intestinal immune cells.

Mucosal surface area of the gut represents an enormous area in direct contact with the environment. In addition to occasional pathogen encounters, the intestinal immune system is constantly exposed to antigens from diet or microbiota.

Gut-associated immune cells maintain a balance between protection against harmful infections and tolerating harmless food-derived antigens and commensals.

Our findings are in agreement with reports that dietary I3C supplementation restored AhR activation in intestinal mucosa under conditions of malnutrition and deprivation of natural AhR ligands. In humans, such malnutrition may result from a severely reduced consumption of vegetables and fruit in favor of a carbohydrate rich, high fat diet.”

https://www.mdpi.com/1422-0067/21/9/3189/htm “Dietary AhR Ligands Regulate AhRR Expression in Intestinal Immune Cells and Intestinal Microbiota Composition”

Our gut microbiota outnumber our human cells. Treat them well with broccoli sprout compounds, resistant starch, and fermentable fibers, and expect reciprocity.