Meeting Abstract

P2.112  Wednesday, Jan. 5  Measurement of glycated hemoglobin in rainbow trout SANTIN, AE*; RODNICK, KJ; Idaho State University, Pocatello; Idaho State University, Pocatello rodnkenn@isu.edu

Glycated hemoglobin (GHb) results from glucose binding non-enzymatically over time to the N-terminus of the β-chain (HbA_1c) and to various lysine residues. Elevated GHb is commonly used to identify individuals with diabetes mellitus and sustained hyperglycemia. In contrast to humans, little is known about GHb in other species. The objective of the current study was to measure GHb in male and female rainbow trout (Oncorhynchus mykiss). Knowing that carnivorous fish have low carbohydrate diets and are practically glucose intolerant, we hypothesized lower GHb values compared to humans. The separation of GHb from non-GHb was performed using an affinity chromatography kit (Helena Laboratories), utilizing a boronate column, which binds GHb. GHb values in rainbow trout (0.5-1.5%) were much lower compared with healthy human values (5-7%), despite similar plasma glucose levels (approximately 4-5 mM), with no differences in sex or age. Other species, both mammalian and non-mammalian, have similar values for GHb as seen in rainbow trout. As a result, unlike humans, GHb in rainbow trout and many other species may not be indicative of long-term glycemia. Possible reasons for observing lower values of GHb in rainbow trout are 1) relative impermeability of the erythrocyte membrane to glucose, 2) interspecies differences in hemoglobin’s amino acid sequence and configuration impeding binding of glucose, or 3) a shorter lifespan of erythrocyte limiting glucose exposure to the hemoglobin.