Plasma Oxysterols in Type 1 and Type 2 Diabetes Mellitus By a Specific and Sensitive LC-MS/MS Method

Presentation Number: SUN 590
Date of Presentation: April 2nd, 2017

Afshin Samadi*1, Alper Gurlek1, Suleyman Nahit Sendur2, Sevilay Karahan1, Filiz Akbıyık1 and Incilay Lay1
1Hacettepe University, Faculty of Medicine, Ankara, Turkey, 2Hacettepe University Medical School, Ankara, Turkey

Abstract

Oxidative stress plays an important role in the pathophysiology of diabetes mellitus (DM). Oxysterols, which resulted from spontaneous or enzymatic oxidation of cholesterol, are potentially non-invasive biomarkers of oxidative stress in vivo. The aim of the present study was to evaluate oxysterol species (7-ketocholesterol and kolestan-3β,5α,6β-triol) as biomarkers of oxidative stress in diabetic patients. 7-ketocholesterol and kolestan-3β,5α,6β-triol were quantified by using a reliable, sensitive and specific LC-MS/MS method in Type 1 (n=26) and type 2 (n=80) DM patients as well as in healthy controls (n=126). The correlation between oxysterols and clinical/biochemical characteristics of the DM patients were also determined. Plasma 7-ketocholesterol levels in patients with DM Type 1 (42.75±11.54 ng/mL) and DM Type 2 (84.80±43.71 ng/mL) were significantly higher than those in control subjects (18.97±3.83 ng/mL) (p<0.001). DM Type 1 and Type 2 patients also demonstrated high levels of kolestan-3β,5α,6β triol (32.30±8.93 ng/mL and 65.69±35.34 ng/mL) compared to healthy controls (10.106±3.94 ng/mL) (p<0.001). Positive correlations of plasma 7-ketocholesterol and kolestan-3β,5α,6β triol levels with BMI, waist circumference, serum total cholesterol, LDL, VLDL, triglyceride and coronary multiple risk factors were observed (p<0.001). No significant relations between oxysterols and HbA1c as well as microvascular complications were determined. In conclusion, plasma oxysterol levels in DM, particularly type 2 diabetic patients, may yield complementary information in oxidative stress and monitoring of macrovascular complications. Furthermore, our LC-MS/MS method for determining oxysterols is the only study in diabetic patients so far. It is more rapid and reliable method when compared to GC-MS method. More effort is needed to establish the clinical utility of oxysterols as sensitive biomarkers of oxidative stress to foresee and monitor the potential complications of DM.

 

Nothing to Disclose: AS, AG, SNS, SK, FA, IL