1 We have reported that andrographolide (ANDRO), an active component of Andrographis paniculata, inhibits in¯ammatory responses by rat neutrophils. To further elucidate the possible mechanism(s) underlying the ANDRO's e ect, N-formyl-methionyl-leucyl-phenylalanine (fMLP)-induced adhesion and transmigration of isolated peripheral human neutrophils were studied. 2 Pretreatment with ANDRO (0.1 ± 10 mM) concentration-dependently prevented fMLP-induced neutrophil adhesion and transmigration. We further examined the up-expression of surface Mac-1 (CD11b/CD18), an essential integrin mediated in neutrophil adhesion and transmigration. ANDRO pretreatment signi®cantly decreased fMLP-induced up-expression of both CD11b and CD18. 4 To clarify whether ROS production impeded by ANDRO could be an antagonism of fMLP binding, phorbol-12-myristate-13-acetate (PMA), a direct protein kinase C (PKC) activator, was introduced to activate ROS production. PMA triggered remarkable ROS production and adhesion, and were partially reversed by ANDRO. This indicated that a PKC-dependent mechanism might be interfered by ANDRO. 5 We conclude that the prevention of ROS production through, at least in part, modulation of PKC-dependent pathway could confer ANDRO the ability to down-regulate Mac-1 up-expression that is essential for neutrophil adhesion and transmigration.
We have previously reported that polysaccharides extracted from fruiting bodies or cultured mycelia of Antrodia camphorata exhibit an anti-hepatitis B virus effect. In this study, we intended to elucidate the anti-inflammatory potency of six mycelial extracts, namely PDBext, CK-ext, CM-ext, CO-ext, CC-ext, and CKO-ext, isolated from mycelia of A. camphorata cultured with six different media including potato dextrose broth (PDB) and five water-soluble fractions from the wood of different Cinnamomum species, i.e. C. kanehirae (CK), C. micranthum (CM), C. osmophloeum (CO), C. camphora (CC), and C. kotoense (CKO), against reactive oxygen species (ROS) production induced by N-formyl-methionyl-leucyl-phenylalanine (fMLP) or phorbol 12-myristate 13-acetate (PMA) in peripheral human neutrophils (PMN) or mononuclear cells (MNC). ROS produced by PMN or MNC act as inflammatory mediators and also signal immune responses. Pretreatment with these mycelial extracts (1^50 Wg ml 31 ) concentration-dependently diminished fMLP-or PMAinduced ROS production in PMN or MNC, as measured by lucigenin-amplified chemiluminescence, with 50% inhibition concentrations (IC 50 ) ranging from 2 to 20 Wg ml 31 . Among these extracts evaluated, CM-ext, CO-ext, or CKO-ext exhibited higher potency than the others. Using high performance liquid chromatography, we identified two lanostane-type compounds, i.e. dehydrosulfurenic acid and 15K-acetyl-dehydrosulfurenic acid, which could be involved in the anti-inflammatory actions of these extracts. The anti-inflammatory actions of these extracts were not due to cytotoxic effects. In summary, these data suggest that extracts from cultured mycelia of A. camphorata display anti-inflammatory effects by inhibiting ROS production in human leukocytes at a pharmacologically applicable concentration. The biological activities of these extracts were further promoted when the culture medium was replaced with water-soluble fractions isolated from the wood of CM, CO or CKO.
We hypothesized that prevention of neutrophil from activation may underlie the myocardial protective effect of the specially processed extract of radix Stephaniae tetrandrae (SPRST). Inflammatory responses in isolated peripheral human neutrophils were studied in the presence or absence of SPRST. SPRST (1-10 microg/ml) concentration-dependently prevented N-formyl-methionyl-leucyl-phenylalanine (fMLP)- or leukotriene B(4) (LTB(4))-induced neutrophil adhesion and transmigration. Comparable results were also observed in neutrophils pretreated with fangchinoline (Fan) or tetrandrine (Tet), two active components in SPRST. It has been reported that neutrophil adhesion/transmigration is mainly Mac-1 (CD11b/CD18)-dependent and could be modulated by reactive oxygen species (ROS) production. SPRST, Tet, and Fan diminished fMLP- or LTB4-induced Mac-1 up-regulation and ROS production. SPRST, Fan, Tet, and verapamil impaired fMLP-induced rapid intracellular alkalization, an essential mechanism for neutrophil ROS production, and [Ca(2+)](i) increment, suggesting that a calcium dependent pathway might be involved. Direct G protein activation by AlF(4)(-) also triggered [Ca(2+)](i) increment and adhesion that could be abolished by pertussis toxin and were partially reversed by SPRST, Fan, and Tet. These results reveal that inhibition of neutrophil adhesion and transmigration may account for SPRST's myocardial protective effect. This effect of SPRST may be mediated by component(s) in addition to Tet and Fan because combination of 0.1 microg/ml of Tet and Fan did not mimic the effect of SPRST. We conclude that SPRST exerts anti-inflammatory effects by interfering with ROS production and Ca(2+) influx through G protein modulation to prevent Mac-1 up-regulation in neutrophil activation.
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