TGFB1 and keloid: Preclinical studies have demonstrated that metabolites such as curcumin, epigallocatechin gallate (EGCG), and asiaticoside modulate key pathways in keloid pathogenesis, including TGF-β/Smad signaling, fibroblast proliferation, and oxidative stress (Gowifel et al., 2020; Adamcakova et al., 2023).