Optimized sensitive and inexpensive method to measure D-lactate as a surrogate marker of methylglyoxal fluxes in metabolically relevant contexts.

Abstract

Plasma D-lactate levels can be considered a surrogate indicator of MG flux. There are commercial methods specifically designed to cover pathological ranges (mmol/l in sepsis or leaky gut) that are not suitable to encompass the metabolically relevant ranges. We modified and optimized the D-lactate Colorimetric Assay kit MAK058 from Sigma adding an ultracentrifugation step, kinetic reading and increasing reaction temperature. We present a modified, optimized and validated method to measure serum D-lactate using a commercial kit to increase the sensitivity of the method to 2 orders of magnitude lower as well as minimizing interferences so that it may be used by researchers to explore the D-lactate pathway in metabolic disorders at a low cost (colorimetric method and a plate reader) and with a much higher specificity.