We hypothesized that serum d-lactate may be increased in vivo in diabetes mellitus as a result of increased glucose flux through the glyoxalase pathway and/or via hepatic ketone metabolism. Levels of d-lactate and related metabolic intermediates were measured in 30 cats with spontaneous diabetes mellitus and in one ketoacidotic nondiabetic cat. Serum d-lactate was significantly (P = .0051) elevated in cats with ketoacidosis (337.2 ± 70.2 μmol/L) as compared with nonketoacidotic diabetic (140.3 ± 58.8) and control (25.0 + 6.5) cats. Two nonketoacidotic cats also had high levels of d-lactate. There was a significant linear correlation (r = .684, P = .0001) between d-lactate and β-hydroxybutyrate concentrations. Serum d-lactate did not correlate with serum glucose (r = .078, P = .6825), and in vitro erythrocyte d-lactate formation did not increase in the presence of hyperglycemia. These data suggest that hepatic ketone metabolism, rather than hyperglycemia, may be a major source of serum d-lactate in diabetics.
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism