Flavonoids and a sesquiterpene lactone from Tanacetum microphyllum inhibit anti-inflammatory mediators in LPS-stimulated mouse peritoneal macrophages.

In our ongoing research into anti-inflammatory compounds from Tanacetum microphyllum, four naturally occurring flavonoids (santin, ermanin, centaureidin and 5,3'-dihydroxy-4'-methoxy-7-methoxycarbonylflavonol) and one sesquiterpene lactone (hydroxyachillin) isolated from this plant, were evaluated as potential inhibitors of some macrophage functions involved in the inflammatory process. These five compounds significantly inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E (2) (PGE (2)) in a concentration-dependent manner. In the tumour necrosis factor-alpha (TNF-alpha) assay, only centaureidin and hydroxyachillin significantly inhibited the accumulation of TNF-alpha. These results indicate that these compounds may contribute to the anti-inflammatory properties of T. microphyllum.