To explore the
anti-allergic and anti-inflammatory effects of extracts of Petasites genus, we studied the effects of
s-petasin, a major
sesquiterpene from Petasites formosanus (a butterbur species) on
asthma and
peritonitis models. In an
ovalbumin-induced mouse
asthma model,
s-petasin significantly inhibited the accumulations of eosinophils, macrophages, and lymphocytes in bronchoalveolar fluids.
S-petasin inhibited the
antigen-induced degranulation of β-hexosamidase but did not inhibit intracellular Ca(2+) increase in RBL-2H3 mast cells.
S-petasin inhibited the LPS induction of iNOS at the
RNA and
protein levels in mouse peritoneal macrophages. Furthermore,
s-petasin inhibited the production of NO (the product of iNOS) in a concentration-dependent manner in the macrophages. Furthermore, in an LPS-induced mouse model of
peritonitis,
s-petasin significantly inhibited the accumulation of polymorpho nuclear and mononuclear leukocytes in peritoneal cavity. This study shows that
s-petasin in Petasites genus has
therapeutic effects on allergic and inflammatory diseases, such as,
asthma and
peritonitis through degranulation inhibition in mast cells, suppression of iNOS induction and production of NO in macrophages, and suppression of inflammatory cell accumulation.