Impact of Exposure to High Concentrations of Fructose on Cell Surface Chemistry and Carbohydrate Metabolism

Abstract

We evaluated the impact high concentrations of fructose have on cell antigenicity and metabolism in vitro. Antigen composition and sugar pools in MEF and bEND‐3 cells were monitored when they were grown in either fructose or glucose. Cell antigenicity was monitored by the expression of ABO blood group antigens. MEF cells cultured in fructose exhibited an increase in A antigen expression compared to glucose. High concentrations of fructose lead to higher concentrations of fructose‐6‐phosphate, which accelerates hexosamine biosynthesis. Metabolic evaluation of carbohydrate pools by mass spectrometry also supports this. While the free sugar pool is similar in MEF cells treated with either sugar, it was noted that the glycoprotein/glycolipid pool is quite different. Cells cultured in fructose posses a 2:1 ratio of hexoses: hexosamines, while cells in glucose contain only hexoses in this pool, showing an increase in hexosamine concentrations in presence of fructose. bEND‐3 cells in fructose and glucose contained similar expression of all antigens monitored as well as carbohydrate pools although less dramatic shifts were also evident. From these results we can observe that fructose does impact hexosamine biosynthesis and therefore, cell antigenicity and carbohydrate metabolism but there is no universal response. While hexosamine production is greatly increased in MEF, which reflects in an increase of A antigens, the effects on bEND‐3 cells were minor. Changes in cell characteristics such as growth rate and tissue function may stem from exposure to different carbohydrates as major energy source.