ALTERATIONS IN ERYTHROCYTE-MEMBRANE FLUIDITY AND FATTY-ACID COMPOSITION IN GLYCOGEN-STORAGE-DISEASE

Liver glycogen storage diseases (GSD) are disorders associated with se vere dyslipidaemia which can induce cell membrane alterations. Reduced erythrocyte membrane fluidity has been associated with ischaemic card iovascular disease. Our study has been designed to investigate membran e erythrocyte fluidity, and to determine its lipid composition and per oxidation parameters. Membrane erythrocyte fluidity has been studied b y electron spin resonance (ESR) with two fatty acid nitroxide probes ( 5NS and 16NS). Twenty-five GSD cases aged 1-27 years and 15 controls a ged 1-28 years were included. The erythrocyte membrane of GSD patients appeared less fluid with the two probes (P < 0.001). The membrane fat ty acid pattern explained this reduced fluidity. Patients showed a rel ative saturated fatty acid (SFA) increase and polyunsaturated fatty ac id (PUFA) decrease which induced lower PUFA/SFA ratio than in controls . We have provided evidence that the PUFA decrease was independent of the oxidative process. These findings should be taken into account for the management of the dietary treatment of GSD patients.