Plasma 15-F2t isoprostane concentrations are increased during acute fructose loading in type 2 diabetes

Objective. - Fructose consumption is increasing worldwide and is likely to play a role in metabolic disorders. Dietary fructose is often recommended for diabetic patients, as this form of carbohydrate leads to a lower postprandial rise in plasma glucose and insulin. However, fructose contributes to the generation of free radicals. The aim of this work was to investigate the acute effects of a fructose load in patients with type 2 diabetes mellitus (T2DM), compared with healthy controls, on several metabolic oxidative biomarkers, particularly plasma 15-F-2t isoprostanes (15-F-2t isoPs). Research design and methods. - Six T2DM patients and six healthy subjects were recruited. All patients underwent a single fructose tolerance test (75 a of anhydrous fructose). Plasma 15-F-2t isoPs concentrations, plasma total antioxidant capacity (TAS) and thiobarbituric acid reactive substances (TBARS) were measured at baseline, and at 60, 120, 180 and 240 min after fructose absorption. Results. - Baseline plasma 15-F-2t isoPs concentrations were significantly increased in T2DM patients compared with controls (310 +/- 47 versus 237 +/- 20 pg/mL, respectively; P < 0.01) and rose significantly (P < 0.01) to 414 +/- 45 pg/mL in diabetic patients. No change in TAS or TBARS was observed in either group. Conclusion. - Plasma 15-F-2t isoPs are increased during acute fructose loading in T2DM. Knowing the potentially deleterious effect of plasma 15-F-2t isoPs-in particular. vascular lesions-and in light of our results, it is necessary to reconsider fructose consumption in T2DM patients, as we can now show, for the first time, a possible association between acute fructose loading and deleterious effects in such patients. (C) 2008 Elsevier Masson SAS. All rights reserved.