Anti-inflammatory effect of methoxyflavonoids from <i>Chiliadenus montanus</i> (<i>Jasonia Montana)</i> growing in Egypt

Abstract

<i>Chiliadenus montanus</i> is a medicinal plant that grows in Sinai Peninsula in Egypt. Phytochemical investigation of <i>C. montanus</i> methanolic extract led to the isolation of five methoxy flavonoids; Chrysosplenol-D <b>(1),</b> 5,7,4'-trihydroxy- 3,3'-dimethoxy flavone <b>(2)</b>, 5,7-dihydroxy -3,3',4'-trimethoxyflavone <b>(3)</b>, Bonanzin <b>(4)</b>, 3,5,6,7,4'-pentamethoxy flavone <b>(5),</b> a sesquiterpene, Cryptomeridiol <b>(6)</b> and stigmast-5,22-dien-3-O-β-D-glucopyranoside <b>(7)</b>. The anti-inflammatory activity of compounds <b>2</b> and <b>5</b> was assessed <i>in vitro</i> on CaCo2 cells stimulated by lipopolysaccharide (LPS). Both compounds downregulated LPS-induced expression of inflammatory cytokines; tumor necrosis factor alpha (TNFα), interleukin 1β (IL1β), nuclear factor kappa B (NFκB), cyclooxygenase 1 (Cox1), cyclooxygenase 2 (Cox2), and 5-lipoxygenase (5Lox). In vivo, both compounds significantly decreased paw edema thickness in rats relative to carrageenan, showing better anti-inflammatory activity than celecoxib (36.98%) after 1 h (46.60% and 48.11%, respectively). An <i>in silico</i> study was performed, where both compounds were docked into the active site of the crystal structure of the human Cox2 enzyme.