טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentKarin Kertesz Rosenfeld
SubjectThe Influence of Advanced Glycation End Products (AGEs) on
Cells in Culture
DepartmentDepartment of Biotechnology and Food Engineering
Supervisors Professor Emeritus Yannai Shmuel (Deceased)
Mr. Werman Moshe


Abstract

The non-enzymatic glycation, also named the Maillard reaction, is a posttranslational modification of proteins, caused by the condensation with reducing sugars. It includes an array of spontaneous complex chain reactions, which produces a heterogeneous group of irreversible adducts, called Advanced Glycation End Products (AGEs).

Another mechanism, termed glycoxidation, includes an oxidation reaction of a free sugar and/or protein-bound sugars produced as a result of glycation, in the presence of metallic ions.

Many studies have shown an association between AGEs and many age- and diabetes-related pathologies, including atherosclerosis, cataract, nephropathy, neuropathy, and Alzheimer’s disease.

The characteristics of the reaction are directly related to the type of sugar involved, the sugar concentration and the reactants’ contact time.

The objectives of this study were to prepare and characterize AGEs formed from different reducing sugars (glucose, fructose and glyceraldehyde) and to investigate the influence of AGEs on the normal rat kidney (NRK) epithelial cell line originating from its proximal tubules.

The results indicate that browning rate, typical AGE fluorescence, typical pentosidine fluorescence, carbonyl level and cross-linking, characterized by SDS-PAGE assay, were compatible with the sugar reactivity. Different sugars produce different or similar AGE compositions at different time intervals. 

AGEs elicited a significant inhibitory effect (p<0.05) on the viability of the cell line, in a kind of sugar- and dose- dependent manner.

The effect of oxidative stress on the cells, caused by exposure to AGEs, was reflected in an increase in carbonyl level in the cells and a decrease in glutathione peroxidase activity.