In vitro and in vivo anti-inflammatory effects of ethanol extract from Acer tegmentosum

Aim of study Acer tegmentosum has been traditionally used for folk medicine to treat hepatic disorders such as hepatitis, hepatic cancer, and hepatic cirrhosis. In this study, we demonstrate the ethno-pharmacological activity of Acer tegmentosum in in vitro and in vivo inflammatory conditions. Results The 70% ethanol extract (At-EE) of Acer tegmentosum dose-dependently diminished the production of nitric oxide (NO), tumour necrosis factor (TNF)-α, and prostaglandin (PG)E2, in lipopolysaccharide (LPS)-activated RAW264.7 cells and peritoneal macrophages, by a transcriptional mechanism. At-EE also suppressed the activation of nuclear factor (NF)-κB, activator protein (AP)-1, and cAMP-responsive element binding (CREB), and simultaneously blocked their upstream inflammatory signalling cascades, including Akt, p38, and JNK. Furthermore, At-EE protected against LPS-induced cell death induced by reactive oxygen species (ROS) and reactive nitrogen species (RNS) and neutralized reactive species generation. In agreement with the in vitro results, orally administered At-EE strongly ameliorated ear oedema formation induced by arachidonic acid. Conclusion At-EE displays strong anti-inflammatory activities in vitro and in vivo, contributing to its major ethno-pharmacological role such as anti-hepatitis remedy and may be applicable to novel anti-inflammatory therapeutics.