Proanthocyanidin B1

Procyanidin B1 is a polyphenolic flavonoid isolated from commonly eaten fruits, binds to TLR4/MD-2 complex, and has anti-inflammatory activity.

Procyanidin B1 is a polyphenolic flavonoid isolated from fruits and fruit juices, binds to TLR4/MD-2 complex, and has anti-inflammatory activity. Procyanidin B1 causes cellular toxicity at concentrations >100 μg/mL. Procyanidin B1 (100 μg/mL) inhibits LPS-induced TNF-α production, and expression of MD-2, TRAF6, NF-κB mRNA, phosphorylated p38 MAPK and NF-κB protein in THP1 cells[1]. Procyanidin B1 (50-100 µM) protects against Aβ oligomer-induced neuronal death. Procyanidin B1 potently inhibits the activation of caspase-3 at 100 µM, caspase-8 at concentrations of 30, 50, and 100 µM and caspase-9 at concentrations of 10, 30, 50, and 100 µM[2]. Procyanidin B1 (10, 20, 30 μM) significantly and dose-dependently induces expression of ACO and CPT1, with no obvious effect on mRNA expression of PPARα[3].

References:
[1]. Xing J, et al. Anti-inflammatory effect of procyanidin B1 on LPS-treated THP1 cells via interaction with the TLR4-MD-2 heterodimer and p38 MAPK and NF-κB signaling. Mol Cell Biochem. 2015 Sep;407(1-2):89-95.
[2]. Kanno H, et al. Protective effects of glycycoumarin and procyanidin B1, active components of traditional Japanese medicine yokukansan, on amyloid β oligomer-induced neuronal death. J Ethnopharmacol. 2015 Jan 15;159:122-8.
[3]. Shimada T, et al. Flavangenol (pine bark extract) and its major component procyanidin B1 enhance fatty acid oxidation in fat-loaded models. Eur J Pharmacol. 2012 Feb 29;677(1-3):147-53.