Radix Paeoniae Rubra Extract

Radix Paeoniae Rubra Extract is a standardized herbal preparation derived from the dried roots of Paeonia lactiflora Pall. or Paeonia veitchii Lynch, both members of the Ranunculaceae family, and has been used for over two millennia in Traditional Chinese Medicine (TCM) to clear heat, cool the blood, activate blood circulation, and resolve stasis, particularly in conditions involving blood stagnation, menstrual disorders, and inflammatory pain. The extract is rich in bioactive monoterpenoid glycosides, with paeoniflorin as the primary marker compound, accounting for up to 5–10% of the dry weight, alongside other constituents such as albiflorin, oxypaeoniflorin, benzoylpaeoniflorin, tannins, flavonoids, and phenolic acids. Pharmacological studies demonstrate that paeoniflorin exerts potent anti-inflammatory effects by inhibiting NF-κB and MAPK signaling pathways, reducing pro-inflammatory cytokines such as TNF-α, IL-6, and IL-1β, and suppressing COX-2 and iNOS expression. It also exhibits significant antioxidant activity by enhancing SOD and GSH-Px levels while reducing MDA accumulation, thereby protecting tissues from oxidative stress-induced damage. In cardiovascular contexts, the extract improves endothelial function, inhibits platelet aggregation, and attenuates atherosclerotic plaque formation through modulation of nitric oxide and endothelin-1 pathways. Neuroprotective effects have been documented in cerebral ischemia-reperfusion models, where the extract reduces infarct volume and neuronal apoptosis via suppression of ferroptosis and mitochondrial dysfunction. Additionally, preclinical evidence supports its antitumor potential, particularly in hepatocellular and breast cancer models, through induction of apoptosis, cell cycle arrest at G0/G1 phase, and inhibition of angiogenesis via VEGF downregulation.