theaflavin-3,3'-digallate

**theaflavin-3,3'-digallate** is a polyphenolic small molecule naturally found in black tea. It possesses a range of biological activities, notably strong anti-inflammatory, antioxidant, antiviral, and anticancer effects. Mechanistically, it acts as a potent inhibitor of platelet-derived growth factor receptor beta (PDGFRβ) signaling, thereby repressing downstream pathways including MAPK/ERK and PI3K/AKT. This leads to suppression of cellular proliferation, migration, and phenotypic switching, especially in vascular smooth muscle cells, contributing to inhibition of neointima formation relevant for vascular injury and atherosclerosis[1][7]. It also inhibits tumor angiogenesis by downregulating hypoxia-inducible factor 1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF)[3]. Additionally, it demonstrates antiviral activities by blocking viral proteases like Zika virus NS2B-3 protease and HIV-1 gp41 and NS2B-3 protease[12], interfering with replication post-entry[5]. Theaflavin-3,3'-digallate suppresses the release of pro-inflammatory cytokines (e.g., TNF-α, IL-1β, IL-6) and prevents nuclear translocation of NF-κB[4], showing benefits in models of acute lung injury and bone resorption[4]. It is studied mainly as a research chemical and is not approved as a pharmaceutical[2][3][4].

Other names

theaflavin 3theaflavin3theaflavin-3theaflavin 3,3′-digallatetheaflavin 3,3''-digallatetheaflavin 3,3'-di-O-gallateTFDG