AHR and Hypertension: Since tryptophan-derived metabolites (e.g., serotonin and melatonin) and tryptophan-related signaling pathway (e.g., AhR) could be an alternative to obtaining the benefits provided by tryptophan, such tryptophan-related reprogramming interventions were recruited in the current review (Figure 3), with a focus on hypertension and kidney disease.