Analyzing serum tryptophan metabolites in patients with gestational diabetes mellitus

Abstract

Abstract Introduction: Although pregnancy is a physiological condition, the secretion of diabetogenic hormones such as growth hormone, corticotropin-releasing hormone, placental lactogen hormone, prolactin and progesterone from the placenta could lead to insulin resistance (IR). In Metabolic Syndrome, obesity and Type1&2 diabetes, a shift in the kynurenine pathway (KP) towards IDO activation is observed. The activation of the IDO leads to the activation of the Aryl hydrocarbon receptor (AhR) and Interleukin-6 (IL-6) also, which may also induce some effects like insulin resistance, β-cell disfunction and increased gluconeogenesis. We hypothesized that the overactivation of IDO and some KP enzymes would be observed in GDM patients, in a similar manner to metabolic syndrome, prediabetes, and diabetes patients. Methods: 50 patients and 50 controls, who applied to the Endocrinology outpatient clinic of Selcuk University Faculty of Medicine were included. Serum triptophan metabolite levels were measured with liquid chromatography tandem mass spectrometry. Results: Tryptophan and KYNA values was found to be lower in the patient group diagnosed with GDM (p<0.001 and p<0.001, respectively). The levels of KYN, 3-OH AA, 3-OH-KYN and KTR were significantly higher in the patient group compared to the control group (p=0.008, p<0.001, p=0.05 and p<0.001, respectively). Conclusions: Understanding the changes that occur in this pathway in GDM patients may provide insight into the development of the disease. Also these tests could be used as supplementary tests in gestational diabetes, which could assist in diagnosis and patient follow-up.