Inhibition of glycosidases by Astragalus lusitanicus and correlation with toxicity.
This study determined whether Astragalus lusitanicus inhibits glycosidase enzymes other than alpha-mannosidase. Plasma collected from lambs given fresh A lusitanicus inhibited beta-glucosidase and beta-galactosidase, indicating the presence of inhibitors in their blood. The residual activity of these enzymes was also modified in tissues of dead animals. beta-glucosidase activity was reduced in liver and kidney specimens with pronounced effects in tissues of animal that presented with prominent clinical signs of poisoning; beta-galactosidase activity was decreased by 88.5 to 95% in kidney, while that of liver remained unchanged. Fractions of the plant butanol extract inhibited the gycosidase enzymes. Chemical analysis revealed the presence of hypaphorin in the extract of A lusitanicus. As a tryptophan derivative, this alkaloid may play a role in the toxicity of this legume.
Abdennebi
E H
EH
Département de Pharmacie, Toxicologie et Biochimie, IAV Hasasn II, Rabat Morocco.
Ouazzani
N
N
Jossang
A
A
Benkouka
F
F
Lamnaouer
D
D
D000818:Animals; D027883:Astragalus Plant / Q000737:chemistry*; D006026:Glycoside Hydrolases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D007668:Kidney / Q000187:drug effects / Q000201:enzymology; D008099:Liver / Q000187:drug effects / Q000201:enzymology; D010936:Plant Extracts / Q000494:pharmacology / Q000633:toxicity; D012756:Sheep
D010936:Plant Extracts; D006026:Glycoside Hydrolases