Tryptophan Metabolism in Digestive and Extra-Digestive Diseases: Mechanisms, Clinical Implications, and Therapeutic Perspectives - Ege Tohumcu; Francesca Sofia Puca; Varol Tunali; Lucia Cerrito; Maria Pallozzi; Leonardo Stella; Marta Maestri; Celeste Ambra Murace; Serena Porcari; Simone Varca; Andrea Severino; Antonio Gasbarrini; et al. (Nutrients, 2026)