Tekin YILDIRIM, Elif BÖREKÇİ, Elif TURAN, Yalçın ARAL, Zeynep Tuğba OZAN, Yeşim GÖÇMEN

The effect of hyperglycemic peak induced by oral glucose tolerance test on the oxidant and antioxidant levels

Background/aim: The possibility of adverse effects of the oral glucose tolerance test (OGTT) carried out for the screening of gestationaldiabetes among pregnant women and fetuses is a frequently discussed topic. The purpose of this study was to investigate the effects ofthe hyperglycemia peak during OGTT on the levels of oxidants and antioxidants in the body.Materials and methods: Eighty individuals who applied to the Outpatient Clinic with suspected diabetes and OGTT indication wereincluded in the study. Glucose, total oxidant capacity status (TOS), total antioxidant capacity (TAS), superoxide dismutase (SOD), andlipid hydroperoxide (LOOH) levels were tested on blood samples collected from these individuals at 0, 60, and 120 min during theOGTT carried out with 75 g of glucose. Oxidative stress index (OSI) was calculated as the ratio of TOS to TAS.Results: While the oxidative parameters TOS and LOOH were significantly increased at 60. min of OGTT, only LOOH was significantlyincreased at 120. min of OGTT. Significant decreases in antioxidative parameters (TAS, SOD) were observed at 60. and 120. min of theOGTT and OSI was significantly increased at 60. and 120. min of the OGTT.Conclusion: Oxidative stress parameters were increased and antioxidative parameters were decreased during the OGTT. However,more extended studies are required to determine the effects of the increased oxidative stress on pregnant women and fetuses.

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