Hyperglycemia and non-enzymatic glycation of serum and tissue proteins in chickens

The objectives of these studies were to determine whether elevated plasma glucose concentrations in broiler breeder chickens (200-250 mg/dl) can result in the non-enzymatic attachment of glucose to serum proteins (fructosamine) and eventual cross-linking of tissue proteins (basement membrane thickness), and to investigate the effects of a factor that may influence this cross-linking process. In response to feeding the satiety factor calcium propionate (CaP, 1.7%), plasma glucose and fructosamine concentrations were increased (P < 0.05) from 1 to 9 weeks of age, whereas concentrations of plasma glucose and fructosamine in feed-restricted chicks were reduced for the first 7 weeks after hatch. In a second study, the age-related increase in kidney capillary basement membrane thickness was prevented (P < 0.05) by feeding the cross-linking inhibitor aminoguanidine (AG, 800 ppm) to 30-week-old broiler breeder hens for 34 weeks. The results from these studies suggest that concentrations of plasma glucose in chickens may, in fact, be exerting long-term detrimental effects on tissue proteins, which can be ameliorated by factors that limit the cross-linking reaction.