Physiology and pathophysiology of polyols

Introduction: Polyols are sugar alcohols linked with the pentose-phosphate pathway (PPP). Recently in two patients, who presented with leucoencephalopathy and hepatopathy, increased concentrations of polyols in body fluids could be measured. In both patients a new enzyme defect within the PPP could be found genetically. So far there is little known about the physiology and pathophysiology of polyols. Therefore we established age-dependent control values, especially of earlyborns and newborns, and tested the neurotoxicity of polyols by using a “neurochip“ in vitro.

Methods: Arabitol, ribitol, xylitol and erythritol were measured in urine samples of healthy controls of different age groups (earlyborns, newborns, toddlers, school-children, adolescents) and in patients with leucoencephalopathies or heptopathies of unknown aetiology. The quantification was performed by gaschromatography. The neuronal network activity of cortical neurons in the presence of D-arabitol and ribitol was tested by using a “neurochip“.

Results: First results indicate differences in the concentrations of poylols depending on age. The patients with leucoencephalopathies or hepatopathies of unknown aetiology did not show any abnormalities in their polyol profile. The polyols D-arabitol and ribitol did not have an acute effect on the spontaneous network activity of cortical neurons.

Conclusion: Polyols can be detected in body fluids by using the gaschromatography. The analysis of polyols should be included in the selective screening of inherited metabolic diseases respecting age-dependent differences in concentrations. Still, the pathophysiology of the polyols in the central nervous system remains unknown and requires more investigation.