Evaluation of the immuno-modulating activity of some active principles isolated from the fruiting bodies of Antrodia camphorata

We have previously isolated some lanostane- and ergostane-type compounds from the fruiting bodies of Antrodia camphorata and Antrodia sp. in our laboratory. In this study, an ergostane-type chemical, named antcin C (Ant C), and three lanostane-type chemicals including sulphurenic acid (SA), eburicoic acid (EA), and dehydroeburicoic acid (DeEA), were examined for their immunomodulating effect against reactive oxygen species (ROS) production induced by N-formyl-meth-ionyl-leucyl-phenylalanine (fMLP) or phorbol-1 2-myristate-1 3-acetate (PMA) in peripheral human neutrophils (PMN) or mononuclear cells (MNC). ROS production by activated-leukocytes is an important inflammatory mediator and also signals immuno-responses. Pretreatment with these four compounds concentration-dependently diminished fMLP- and PMA-induced ROS production in PMN, as measured by lucigenin-amplified chemiluminescence, with IC50 values (jiM) of 16.9±4.2, 43.9±14 and 144.8±13 for Ant C, EA and DeEA, respectively. These compounds were relatively less effective in the inhibition of ROS production by MNC with IC50 values around 200 jiM. The anti-oxidative actions of these drugs were not due to cytotoxic effects because no significant difference in cell viability was observed as compared to the vehicle control group. In summary, our data suggests that inhibition of ROS production in leukocytes by these active principles could be responsible for the immuno-modulating effects of A. camphorata.