Analgesic effect of <i>Centaurium erythraea</i> and molecular docking investigation of the major component swertiamarin

Centaurium erythraea Rafn is employed in Algerian traditional medicine for treating pain. The analgesic activity of the ethanolic extract (EE) from the flowering aerial parts of this plant was examined, and molecular docking of the main bioactive compound was performed. The EE, characterised by the iridoid swertiamarin, was administered to Wistar albino rats in pain models. Peripheral analgesic activity was evaluated using the acetic acid-induced writhing test, and a hot plate test was performed for central antinociceptive activity evaluation. Treatment with EE significantly decreased rats’ writhing induced by acetic acid suggesting peripheral analgesic activity. Furthermore, the elevation of mean basal reaction time in the hot plate method indicated central analgesic activity. Molecular docking studies showed good docking energy with acceptable binding interactions of swertiamarin with cyclooxygenase-2 protein. This supports the analgesic activity of C. erythraea EE, justifying the traditional use of the plant as an analgesic herbal remedy.</p

Glycosyl flavonoid profile, <i>in vivo</i> antidiabetic and <i>in vitro</i> antioxidant properties of <i>Linaria reflexa</i> Desf.

<p>Aerial parts of <i>Linaria reflexa</i>, used in North African folk medicine for treating certain skin diseases, were investigated by HPLC–DAD–ESI/MS technique able to identify the glycosyl flavonoids pectolinarin (<b>1</b>), isolinariin A (<b>2</b>), isolinariin B (<b>3</b>), linariin (<b>4</b>), isolinariin D (<b>5</b>) and isolinariin E (<b>6</b>) as the most abundant components in both hydroalcoholic (HAE) and ultrasound-assisted (UAE) extracts profiles. Metabolite <b>5</b>, isolated and fully characterised by extensive nuclear magnetic resonance (NMR) analysis, has been very recently reported from <i>L. japonica</i> together with the compound <b>6</b>. Good antioxidant activities (DPPH radical scavenging, <i>β</i>-carotene bleaching and reducing power assays) were observed for the extracts. The remarkable antidiabetic activity displayed by UAE (300 mg/kg) has yielded the most marked decrease in blood glucose levels of the alloxan diabetic rats (−72.09%), greater than the effects by the drug glybenclamide (−63.29%). This study reports the first correlation of antidiabetic activity of <i>Linaria</i> sp. extracts with their chemical composition.</p