fructosyl-lysine and Body-Weight

A differing individual expression of fructosyllysine-specific receptors has been found on the monocytes of 90 insulin-dependent diabetic patients and 101 healthy control subjects. The degree of receptor expression is neither age- nor sex-dependent; however, in the diabetic group it correlates significantly with the severity and age of onset of diabetic microangiopathy. To interpret the results of the human study, spontaneously diabetic and non-diabetic BB/OK rats were used to estimate tissue content of glucose-modified proteins and capillary basement membrane thickness in relation to the receptor expression on macrophages. In non-diabetic and diabetic rats no correlation was found between receptor expression and tissue content (i.e. artery, nerve) of fructosyllsine and fluorescent advanced glycation end products. However, animals which express the fructosyllysine receptor showed a greater increase in muscle capillary basement membrane thickness. There are indications that fructosyllysine receptor expression is positively associated with indices of diabetic complications such as microangiopathy and/or capillary basement membrane thickening.

Topics: Adult; Age of Onset; Animals; Blood Glucose; Body Weight; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Diabetic Neuropathies; Diabetic Retinopathy; Female; Fructosamine; Glycated Hemoglobin; Humans; Lysine; Macrophages; Male; Membrane Proteins; Middle Aged; Monocytes; Nuclear Proteins; Probability; Rats; Rats, Inbred BB; Reference Values; RNA-Binding Proteins

Two experiments lasting 10 vs. 8 weeks respectively were conducted in order to determine the effects of feeding heated proteins (casein + glucose, 65 degrees C for 4 days) on histopathological alterations in the kidneys of rats. Histological examinations showed enlarged epithelial cells and cell nuclei in the pars recta of the proximal tubules (inner stripe of the inner kidney cortex zone) beginning after two weeks of the test. The differences in the average size of the nuclei were significant after a feeding period of 6, 8 or 10 weeks (44 rats in the test group vs. 36 rats in the control group respectively). In this way the alterations are very similar to that which are induced by lysinoalanine. The substance causing the lesions seems not to be fructoselysine although it was present in the heat damaged diets in concentrations of 16,000-23,000 ppm but is suggested among the substances formed in the early and advanced stage of Maillard reaction.

Topics: Animals; Body Weight; Dietary Proteins; Hot Temperature; Kidney; Kidney Tubules, Proximal; Lysine; Male; Organ Size; Protein Denaturation; Rats; Rats, Inbred Strains; Time Factors