L(+)‎ and D(-)‎ Lactate Are Increased in Plasma and Urine Samples of Type 2 Diabetes as Measured by a Simultaneous Quantification of L(+)‎ and D(-)‎ Lactate by Reversed-Phase Liquid Chromatography Tandem Mass Spectrometry

الملخص EN

Plasma and urinary levels of D-lactate have been linked to the presence of diabetes.

Previously developed techniques have shown several limitations to further evaluate D-lactate as a biomarker for this condition.

Methods.

D- and L-lactate were quantified using ultraperformance liquid chromatography tandem mass spectrometry with labelled internal standard.

Samples were derivatized with diacetyl-L-tartaric anhydride and separated on a C18-reversed phase column.

D- and L-lactate were analysed in plasma and urine of controls, patients with inflammatory bowel disease (IBD), and patients with type 2 diabetes (T2DM).

Results.

Quantitative analysis of D- and L-lactate was achieved successfully.

Calibration curves were linear (r2>0.99) over the physiological and pathophysiological ranges.

Recoveries for urine and plasma were between 96% and 113%.

Inter- and intra-assay variations were between 2% and 9%.

The limits of detection of D-lactate and L-lactate in plasma were 0.7 μmol/L and 0.2 μmol/L, respectively.

The limits of detection of D-lactate and L-lactate in urine were 8.1 nmol/mmol creatinine and 4.4 nmol/mmol creatinine, respectively.

Plasma and urinary levels of D- and L-lactate were increased in patients with IBD and T2DM as compared with controls.

Conclusion.

The presented method proved to be suitable for the quantification of D- and L-lactate and opens the possibility to explore the use of D-lactate as a biomarker.