A high-throughput colorimetric-assay for monitoring glucose consumption by cultured trophoblast cells and placental tissue.

Diabetes mellitus is associated with abnormalities in placental structure and function and significant pregnancy complications. In vitro studies to investigate the effect of hyperglycaemia on trophoblast structure and function require an accurate, inexpensive and reliable assay to monitor the concentration of glucose in culture medium. We have modified and validated an existing protocol for use with a 96-well microplate. This provides a specific, high-throughput assay which accurately measures culture media glucose concentrations between 7 and 30 mM, without spectral interferences by phenol red or sera. Use of this assay revealed that the concentration of glucose in BeWo cell cultures remains stable for 48 h. In contrast placental explants rapidly consume glucose thus the concentration in culture media significantly decreases over 12 h necessitating more frequent replenishment in order to maintain the desired concentration. We therefore advise researchers to monitor glucose concentrations in in vitro investigations modelling the effect of diabetes mellitus on placental structure and function.