Phytocompounds from Cryptomeria japonica exhibit potent bioactivities on modulating inflammatory mediators and hepatoprotection

Cryptomeria japonica D.Don is an industrially important plantation tree species in Asia countries. This study aims to characterize the anti-inflammatory and hepatoprotective activities of the phytocompounds from C. japonica wood on LPS- or TPA-induced expression of proinflammatory mediators and CCl₄-induced acute liver injury in mice. A CJH7–2 fraction was purified from the wood hexane extract of C. japonica using silica gel column chromatography, which exhibits significant activities, at 5µg/ml, on inhibition of NO production and iNOS expression and up-regulating HO-1 expression in LPS-stimulated macrophages. CJH7–2 also potently inhibits TPA-induced COX-2 protein expression in mouse skin (1mg/200µl/site) and COX-2 enzymatic activity (IC₅₀=5µg/ml). CJH7–2 (10mg/kg BW) can prevent CCl₄-induced liver injury and aminotranferases activities in mice. Chemical fingerprinting analysis showed that terpenes are the major bioactive compounds in the CJH7–2 fraction. This is the first study to demonstrate that chemical constituents from wood extract of C. japonica possess anti-inflammatory activity in vitro and in vivo that may play a role in hepatoprotection. The results also suggest that the great potential of C. japonica compounds need further development as therapeutic agent for inflammatory disorders.