Castanospermine analogues: their inhibition of glycoprotein processing alpha-glucosidases from porcine kidney and B16F10 cells.
We have used a simple and efficient procedure for the synthesis of N-5-carboxypentyl-1-deoxynojirimycin, an affinity ligand for alpha-glucosidase I (Bernotas, R. C. and Ganem, B., Biochem. J., 270, 539-540, 1990). The affinity gel was used to purify alpha-glucosidase I in one step from crude extract. In subsequent steps, partially purified alpha-glucosidase II was obtained. We have synthesized several analogues of castanospermine and studied their inhibition of alpha-glucosidase I in vitro using purified alpha-glucosidase I and in vivo in cultured B16F10 cells. Although the castanospermine analogues were significantly less active against the purified enzyme (IC50 approximately 1-23 micrograms/ml) as compared to castanospermine (IC50 = 0.02 microgram/ml), several compounds had up to 30-fold higher activity than castanospermine against alpha-glucosidase I in B16F10 cells, based on the accumulation of G3M7-9N2 oligosaccharide-containing glycoproteins. These results suggest that these analogues with lipophilic side chains cross the membrane barrier more efficiently than castanospermine. Once inside the cell, they may be converted to their active metabolite, castanospermine, by cellular esterases to give enzyme inhibition.
Kang
M S
MS
Marion Merrell Dow Inc., Cincinnati, OH 45215, USA.
Liu
P S
PS
Bernotas
R C
RC
Harry
B S
BS
Sunkara
P S
PS
D000818:Animals; D002240:Carbohydrate Sequence; D002460:Cell Line; D002846:Chromatography, Affinity; D006020:Glycopeptides / Q000737:chemistry / Q000302:isolation & purification; D006023:Glycoproteins / Q000096:biosynthesis*; D065089:Glycoside Hydrolase Inhibitors; D006031:Glycosylation; D007212:Indolizines / Q000138:chemical synthesis / Q000494:pharmacology*; D007668:Kidney / Q000201:enzymology*; D008969:Molecular Sequence Data; D015394:Molecular Structure; D011499:Protein Processing, Post-Translational; D013329:Structure-Activity Relationship; D013552:Swine; D000520:alpha-Glucosidases / Q000302:isolation & purification; D054836:Indolizidines
D006020:Glycopeptides; D006023:Glycoproteins; D065089:Glycoside Hydrolase Inhibitors; D007212:Indolizines; D000520:alpha-Glucosidases; C037806:castanospermine; D054836:Indolizidines