BACKGROUND:
The
stem bark of
Kalopanax pictus (KP) has been used in
traditional medicine to treat rheumatoidal
arthritis, neurotic
pain and
diabetes mellitus in
China and
Korea. In this study, the mechanism responsible for anti-inflammatory effects of KP was investigated.
METHODS:
We examined the effects of KP on NO
production,
nitric oxide synthase (iNOS) and HO-1 expression,
NF-kappaB, Nrf2 and MAPK activation in
mouse peritoneal macrophages.
RESULTS:
The aqueous extract of KP inhibited LPS-induced NO
secretion as well as inducible iNOS expression, without affecting
cell viability. KP suppressed LPS-induced
NF-kappaB activation,
phosphorylation and degradation of
IkappaB-alpha,
phosphorylation of
extracellular signal-regulated kinase 1/2 (ERK1/2) and
c-Jun N-terminal kinase (JNK). Furthermore, KP induced HO-1 expression and Nrf2 nuclear translocation.
CONCLUSION:
These results suggest that KP has the inhibitory effects on LPS-induced NO
production in
macrophages through
NF-kappaB suppression and HO-1 induction.