Advanced glycation end-products in patients with chronic alcohol misuse

Aims: The aim of our study was to determine serum levels of advanced glycation end-products (AGE) in patients with chronic alcohol misuse and to examine their relationship to markers of nutrition and inflammation. Methods: The study group consisted of 23 heavy alcohol drinkers treated for chronic alcohol misuse and 22 healthy controls. Studied parameters included AGE (fluorescence, CML-carboxymethyllysine and pentosidine), lipids, glucose, albumin, leptin, prealbumin, C-reactive protein (CRP) and pregnancy-associated plasma protein A (PAPP-A). Results: AGE fluorescence was significantly higher in chronic alcoholic patients than in healthy subjects (4.3+/-0.7x10(3) vs 3.7+/-0.5x10(3) AU/g protein, P<0.005), while CML was only slightly but not significantly elevated (569.1+/-106.6 vs 545.5+/-85.8 mug/l) and pentosidine levels did not differ (105.4+/-29 vs 102.2+/-23 nmol/l). In alcoholics, AGE correlate significantly negatively with leptin (r=-0.46, P<0.05) and pentosidine with prealbumin (r=-0.43, P<0.05), otherwise there was no relationship between AGE and other biochemical parameters (glucose, cholesterol, albumin, CRP, PAPP-A). Conclusion: Our findings suggest a more complex relationship among advanced glycation, oxidative stress and metabolism of ethanol and their link to nutrition and nutrition-associated parameters. AGE as a result of oxidative stress might be similarly linked to increased cardiovascular risk of heavy alcohol drinkers, as are malnutrition and inflammation; however, further studies are needed to confirm this hypothesis.