Anti-inflammatory activities of two flavanones, sigmoidin A and sigmoidin B, from Erythrina sigmoidea.
Two prenylated flavanones isolated from Erythrina sigmoidea Hua (sigmoidin A and sigmoidin B) were studied for their ability to inhibit the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical and arachidonic acid metabolism. In addition, the compounds were studied in two experimental models of inflammation induced in mouse ears by 12- O-tetradecanoylphorbol 13-acetate (TPA) and the phospholipase A (2)-induced mouse paw oedema. Both sigmoidins A and B proved to be potent scavengers of the DPPH radical, while the study of the inhibition of arachidonic acid metabolism demonstrated that these same compounds were selective inhibitors of 5-lipoxygenase, with no effect on cyclooxygenase-1 activity. Dose-response inhibitor potency was established for sigmoidin A (IC (50) = 31 microM). In the assay of phospholipase A (2)-induced mouse paw oedema, only the sigmoidin B derivative inhibited oedema formation at 60 min, showing a percentage of inhibition below that obtained with cyproheptadine (59 % vs. 74 %). In the TPA test, sigmoidins A and B decreased the induced oedema by 89 % and 83 %, respectively. This is the first time that the anti-inflammatory activity and antioxidant properties of these prenylflavanones have been reported. The results indicate that the compounds have different mechanisms of action depending on whether one or two prenyl groups are present in ring B.
Laboratory of Animal Physiology, Department of Animal Biology and Physiology, Faculty of Science, University of Yaoundé 1, Yaoundé, Cameroon.
Dieudonné
D
Njamen
Joseph Tanyi
JT
Mbafor
Zacharias Tanee
ZT
Fomum
Albert
A
Kamanyi
Jean-Claude
JC
Mbanya
M Carmen
MC
Recio
Rosa M
RM
Giner
Salvador
S
Máñez
José Luis
JL
Ríos
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D001713:Biphenyl Compounds; D004305:Dose-Response Relationship, Drug; D004487:Edema / Q000139:chemically induced / Q000517:prevention & control*; D004895:Erythrina; D005260:Female; D044950:Flavanones / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D005419:Flavonoids / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D016166:Free Radical Scavengers / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D051379:Mice; D010741:Phospholipases A; D008517:Phytotherapy; D010851:Picrates / Q000737:chemistry; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D051381:Rats; D017208:Rats, Wistar; D013755:Tetradecanoylphorbol Acetate
D000894:Anti-Inflammatory Agents, Non-Steroidal; D001713:Biphenyl Compounds; D044950:Flavanones; D005419:Flavonoids; D016166:Free Radical Scavengers; D010851:Picrates; D010936:Plant Extracts; C064222:sigmoidin B; C064221:sigmoidin A; C004931:1,1-diphenyl-2-picrylhydrazyl; D010741:Phospholipases A; D013755:Tetradecanoylphorbol Acetate