Anti-inflammatory and membrane-stabilizing stigmastane steroids from Alchornea floribunda leaves.
Alchornea floribunda (Euphorbiaceae) leaves are widely used in African ethnomedicine for the management of acute and chronic inflammatory disorders. In the present study, bioactivity-guided fractionation led to the isolation of two known (1 and 3) and one new (2) stigmastane steroids from the hexane extract of Alchornea floribunda leaves. The anti-inflammatory activities of these compounds were evaluated using IN VITRO and IN VIVO animal models. The compounds 1, 2, and 3 at 50 and 100 microg/ear significantly (p < 0.05) inhibited xylene-induced ear edema in mice in a dose-dependent manner. The topical anti-inflammatory effect of 1 and 2 are significantly (p < 0.05) higher than that of indomethacin and prednisolone. At 20 mg/kg (i. p.), all the compounds significantly (p < 0.05) inhibited acute inflammation induced by subplantar injection of egg albumen in rats. Compound 1 exhibited an anti-inflammatory effect (50.9 % edema inhibition) comparable (p < 0.05) to that of prednisolone (48.0 % edema inhibition) at 3 h. Compounds 1, 2, and 3 (50 microg/mL) significantly (p < 0.05) inhibited heat-induced haemolysis of human erythrocytes in vitro, but had no effect on hypotonicity-induced hemolysis. The compounds were elucidated as (24R)-5alpha-stigmast-3,6-dione ( 1), 5alpha-stigmast - 23-ene-3,6-dione ( 2), and 3beta-hydroxy-5alpha-stigmast-24-ene ( 3) by spectral analysis. The results of this study show that these compounds may, in part, account for the anti-inflammatory effect of Alchornea floribunda leaves. This is the first report on the isolation and structure elucidation of these anti-inflammatory steroids from Alchornea floribunda leaves.
Okoye
Festus B C
FB
Department of Pharmaceutical Chemistry, University of Nigeria, Nsukka, Enugu State, Nigeria. basdenc@yahoo.com
Osadebe
Patience O
PO
Proksch
Peter
P
Edrada-Ebel
Ru Angelie
RA
Nworu
Chukwuemeka S
CS
Esimone
Charles O
CO
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use*; D002462:Cell Membrane / Q000187:drug effects*; D002783:Cholestenones / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004487:Edema / Q000139:chemically induced / Q000188:drug therapy*; D004912:Erythrocytes / Q000187:drug effects; D019665:Euphorbiaceae / Q000737:chemistry*; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D051379:Mice; D015394:Molecular Structure; D010840:Phytosterols / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use*; D008517:Phytotherapy; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use*; D018515:Plant Leaves; D051381:Rats; D017208:Rats, Wistar; D014992:Xylenes
C549090:5alpha-stigmastane-23-ene-3,6-dione; D000893:Anti-Inflammatory Agents; D002783:Cholestenones; D010840:Phytosterols; D010936:Plant Extracts; D014992:Xylenes