Anti-inflammatory effects of water-soluble fractions from Artemisia species using the LPS-induced inflammatory response in primary rat astrocyte cultures

Abstract

Water-soluble fractions have been purified from the crude aqueous extracts of Artemisia species, especially from Artemisia folum (AVF3) and Artemisia iwayomogi Kitam. (AIP1). The herbs are traditionally used as the medicinal plant to prevent or treat a number of liver diseases in Asia [1]. The AIP1 fraction has been shown to have diverse immuno-modulating activities including, anti-apoptosis and anti-cancer effects in our previous works [2, 3]. In this study, we have investigated the anti-inflammatory activity of the fractions using the LPS-induced inflammation model with primary rat astrocyte cultures. The treatment of the astrocyte culture either with AVF3 or AIP1 resulted in the suppression of the NO production by the LPS treatment, which was comparable to that of the dexamethasone treatment. Quantitative real-time PCR analysis revealed that the expression of iNOS gene was significantly suppressed by the samples, indicating that the inhibition of NO production could result from an inhibitory effect on iNOS gene transcription. The treatment also suppressed the up-regulation of the pro-inflammatory IL-6 and MIP-1β genes as the dexamethasone treatment. These results clearly demonstrate that the water-soluble fractions from Artemisia species might modulate the inflammatory response in brain astrocytes. Since NO production in brain astrocytes is important in the pathogenesis of a number of brain inflammatory diseases such as multiple sclerosis and Alzheimer's disease, the anti-inflammatory effect of the fraction could have considerable value for the protection or the treatment of the neurodegenerative diseases.