Graded sensitiveness of the various retinal neuron populations on the glyoxal-mediated formation of advanced glycation end products and ways of protection

• Published in: Graefe's archive for clinical and experimental ophthalmology 2003-03, Vol.241 (3), p.213-225
• Main Authors: REBER, Friedemann, GEFFARTH, Romy, KASPER, Michael, REICHENBACH, Andreas, SCHLEICHER, Erwin D, SIEGNER, Axel, FUNK, Richard H. W
• Format: Article
• Language: English
• Subjects: Acetylcysteine - pharmacology; Animals; Apoptosis - drug effects; Associated diseases and complications; bcl-2-Associated X Protein; Biological and medical sciences; Caspase 3; Caspases - metabolism; Diabetes. Impaired glucose tolerance; Dose-Response Relationship, Drug; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Female; Glycation End Products, Advanced - metabolism; Glyoxal - toxicity; Guanidines - pharmacology; Immunoenzyme Techniques; In Situ Nick-End Labeling; Lysine - analogs & derivatives; Lysine - metabolism; Male; Medical sciences; Neurons - drug effects; Neurons - metabolism; Neurons - pathology; Niacinamide - pharmacology; Ophthalmology; Organ Culture Techniques; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-bcl-2; Rats; Rats, Sprague-Dawley; Retina - drug effects; Retina - metabolism; Retina - pathology; Thioctic Acid - pharmacology; Vanadates - pharmacology
• ISSN: 0721-832X; 1435-702X
• DOI: 10.1007/s00417-002-0528-1

The accumulation of advanced glycation end products (AGEs) in retinal cells is known to be associated with the risk of diabetic retinopathy. To develop a model of AGE-related metabolic stress in retinal organ cultures, we investigated the accumulation of a typical glycoxidation product (N(epsilon)-[carboxymethyl] lysine [CML]) and its possible pro-apoptotic effects on different retinal cell populations. Retinal organ cultures (rat) were kept for 9 h in the Ames medium containing 0 (control), 5, 25, 50, 150, 300 and 800 micro M glyoxal. The expression of bax, active caspase-3, and the accumulation of CML were studied by using immunohistochemistry after the paraffin embedding of retinal explants. Apoptosis was studied using the terminal deoxynucleotidyl transferase-mediated dUTP digoxigenin nick end labeling (TUNEL) test and electron microscopy. Alpha lipoic acid (alpha-LA), sodium metavanadate (NaVO(3)), N-acetylcysteine (NAC), aminoguanidine (AG), and nicotinamide (NA) were used to influence glyoxal effects in organ cultures. In cultured normal non-diabetic retinae, small amounts of CML and the apoptosis-promoting factors bax and active caspase-3 were present. CML, bax and active caspase-3 increased after incubation with glyoxal. Incubation with glyoxal (