Plasma gangliosides correlate with disease stages and symptom severity in Huntington disease carriers

BackgroundGangliosides - glycosphingolipids that modulate cell signaling and neuronal functions - are decreased in Huntingtons disease (HD) models and patients brains. Restoring ganglioside GM1 has therapeutic benefits in HD mice, slowing neurodegeneration and improving symptoms. This suggests gangliosides might contribute to HD pathogenesis. However, their link to disease severity and progression in patients remains unclear. ObjectivesThis study examined plasma ganglioside differences between HD gene carriers and controls, and their prognostic potential. MethodsPlasma gangliosides were quantified in 67 HD carriers and 46 healthy participants, using liquid chromatography-tandem mass spectrometry. Statistical modelling assessed associations with clinical measures and prognostic potential. ResultsLevels of most gangliosides were similar between groups, but GM3 was higher and GT1b lower in HD carriers. Within the HD group, higher GM2 levels correlated with better cognition, and higher GM1 and GD1a with greater functional capacity and independence. Higher GM1 predicted HD status, but its decline and an increase in GD3 were strongly associated with disease progression. Individual gangliosides had limited disease classification ability. ConclusionsThe correlation between higher GM2, GD1a and GM1 and milder symptoms suggests a protective role of these gangliosides in HD. The association between higher GM1 levels and HD status, along with its decline predicting disease progression, suggests GM1 increase may be a compensatory neuroprotective mechanism that deteriorates over time. While plasma gangliosides are not strong disease classifiers, our findings provide novel insights into their role in HD progression and prognostic potential.