Lung collagen hydroxyproline, uronic acid, hexosamine, serum sialic acid, [gamma]-glutamyl transpeptidase, vascular endothelial growth factor (VEGF), granulocyte monocyte colony-stimulating factor and other cytokine levels were significantly lowered in the treated group of animals.
Hexosamine was estimated in the presence of Ehrlich's reagent and glucosamine was used as standard (Elson and Morgan 1933).
At biochemical level, during hyperglycemic conditions, several alterations have been described in different pathways as polyol, hexosamine
, protein kinase C, and advanced glycation end-product (AGE) metabolisms .
The latter can be organically synthesized through the hexosamine
pathway, an alternative metabolic route to glycolysis, which is esteemed to consume up to 5% of glucose in adipocyte cultures .
It has been suggested that insulin increases leptin production indirectly via its effects to increase glucose utilization and increased flux of glucose in adipose tissue shown to stimulate the hexosamine
pathway andleptinproduction 45].
The Collagen, Hyxdroxyproline, Hexosamine
and Elastin content of the healing tissue were determined.
The higher amino sugar concentrations may be attributed to a decreased mineralisation of hexosamines
and muramic acid due to more recalcitrant litter and/or to increased contribution of microbial substances at the reforestation site as indicated by the presence of visible fungal hyphae, coupled with an increasing population of bacteria living upon the residues of fungi (Troeh and Thompson 1993).
In the SM of several oysters, hexosamines
or hexoses and uronic acids are found in combination with sulfate (Crenshaw, 1972; Samata and Krampitz, 1982).
Gastric wall mucus, an obligatory component of which is hexosamines
, is thought to play an important role as a defensive factor against gastrointestinal damage (Davenport, 1968).
In oocytes of the amphibians Bufo arenarum, mannose is the most abundant carbohydrate residue in egg jelly, and it is involved in recognition of sperm (Omata & Katagiri 1996), whereas the sulfated glycoproteins rich in hexosamines
, fucose, and galactose found in Xenopus laevis egg jelly act in a similar manner (Yurewicz et al.
It has been proposed that glucosamine sulfate could potentially alter glucose control, specifically interfering with the hexosamine
biosynthesis pathway, (25) and as such down-regulating cellular glucose uptake and leading to hypergylcemia and insulin resistance.
It has been suggested that the hexosamine
biosynthetic pathway is involved in the pathogenesis of insulin resistance in patients with type 2 diabetes mellitus because the activity of the rate-limiting enzyme of this pathway, glutamine:fructose-6-phosphate amidotransferase (EC 188.8.131.52), is increased in skeletal muscle of patients with type 2 diabetes mellitus (1).