Abstract

Schizandrae fructus is a medicinal fruit that has long been used for the treatment of dyspnea, cough, mouth dryness, amnesia, and nocturnal emission. Several studies have reported the anti-asthmatic, anti-hepatotoxic, anti-oxidative, and anti-diabetic effects of Schizandrae fructus; however little is known about the mechanisms by which the anti-inflammatory of this herb. In this study, we evaluated the effects of aqueous extract of Schizandrae fructus on lipopolysaccharide (LPS)-induced inflammation in mouse BV2 microglial cells. To accomplish this, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, reverse transcription-polymerase chain reaction (RT-PCR), Western blot, prostaglandin E₂ (PGE₂) immunoassay, and nitric oxide (NO) detection were conducted. The results revealed that the aqueous extract of Schizandrae fructus suppressed PGE₂ synthesis and NO production by inhibiting the LPS-stimulated enhancement of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression in mouse BV2 microglial cells. This extract also suppressed the expression of phosphorylated forms of mitogen-activated protein kinases (MAPKs). These results demonstrate that Schizandrae fructus may exert anti-inflammatory, and that these effects are associated with the suppression of COX-2 and iNOS expressions via down-regulation of MAPKs. (Korean J Str Res 2009;17:415∼424)

• Keywords: Schizandrae fructus, Mitogen-activated protein kinase, Nitric oxide, Prostaglandin E₂;