Procyanidin B1，5MG，SML4314-5MG，Sigma

Biochem/physiol Actions

Procyanidin B1, a natural biflavonoid, functions as a potent antioxidant and anti-inflammatory agent, mitigating oxidative stress and inflammation associated with chronic diseases. It exhibits multi-target activity, directly interacting with enzymes like Caspases and COX-2, the Kv10.1 ion channel (IC50 ~10 µM), and the TLR4/MD-2 complex, while inhibiting key signaling pathways including NF-κB, MAPK, and PI3K/Akt. Mechanistically, Procyanidin B1 promotes cancer cell apoptosis (activating Caspase-3, upregulating Bax), potentially regulating ferroptosis via the Nrf2/HO-1/Keap-1 pathway, induces cell cycle arrest (downregulating Cyclins), suppresses inflammatory gene expression (TNF-α, IL-6), provides neuroprotection (effective at 50-100 µM vs Aβ), and regulates metabolic pathways. In vitro and in vivo evidence supports its efficacy in reducing tumor growth and inflammation, demonstrated by decreased biomarkers like TNF-α, IL-6, and Ki67, and increased activated Caspase-3, although systemic delivery faces challenges due to its low cell permeability and oral bioavailability as an intact dimer.