Glucosamine-induced endoplasmic reticulum (ER) stress was recently shown to specifically reduce apolipoprotein B-100 (apoB-100) secretion by enhancing the proteasomal degradation of apoB-100. Here, we examined the mechanisms linking glucosamine-induced ER stress and apoB-lipoprotein biogenesis. Trypsin sensitivity studies suggested glucosamine-induced changes in apoB-100 conformation. Endoglyco...

Glucosamine is widely used to relieve symptoms from osteoarthritis. Its safety and effects on glucose metabolism are critically evaluated in this review. The LD50 of oral glucosamine in animals is approximately 8000 mg/kg with no adverse effects at 2700 mg/kg for 12 months. Because altered glucose metabolism can be associated with parenteral administration of large doses of glucosamine in anima...

Accelerated atherosclerosis is one of the major vascular complications of diabetes. Factors including hyperglycemia and hyperinsulinemia may contribute to accelerated vascular disease. Among the several mechanisms proposed to explain the link between hyperglycemia and vascular dysfunction is the hexosamine pathway, where glucose is converted to glucosamine. Although some animal experiments sugg...

A model for computing image ow in image sequences containing a very wide range of instantaneous ows is proposed. This model integrates the spatio-temporal image derivatives from multiple temporal scales to provide both reliable and accurate instantaneous ow estimates. The integration employs robust regression and automatic scale weighting in a generalized brightness constancy framework. In addi...

Heart, Emma, Woo S. Choi, and Chin K. Sung. Glucosamine-induced insulin resistance in 3T3-L1 adipocytes. Am. J. Physiol. Endocrinol. Metab. 278: E103–E112, 2000.—To study molecular mechanisms for glucosamine-induced insulin resistance, we induced complete and reversible insulin resistance in 3T3-L1 adipocytes with glucosamine in a doseand time-dependent manner (maximal effects at 50 mM glucosam...

As estimated from initial uptake rates, the uptake of glucosamine-l-14C by cultured Novikoff rat hepatoma cells in glucose-free basal medium follows normal Michaelis-Menten kinetics, with an apparent Km of about 20 mM. Since glucosamine is not accumulated by the cells against a concentration gradient, the main mode of uptake is by facilitated diffusion, but other evidence indicates that glucosa...

OBJECTIVE Pharmacokinetic data on glucosamine are scant, limiting the understanding of glucosamine sulfate mechanism of action in support of its treatment effects in osteoarthritis. This study investigated the oral pharmacokinetics and dose-proportionality of glucosamine after administration of the patented crystalline glucosamine sulfate in man. METHODS Twelve healthy volunteers received thr...

The formation of N-methyl-L-glucosamine moiety of streptomycin from D-glucosamine by Streptomyces griseus was studied. The addition of thymine to the culture medium stimulated the formation of streptomycin and the incorporation of D-glucosamine into N-methyl-L-glucosamine moiety. During a study of sugar nucleotides in the mycelia, a novel UDP-amino sugar was isolated. The compound was formed be...