Figure 4.

Correlation between sialic acid metabolism and Krebs cycle (A) and results of GC-MS/MS analysis of the intermediates of TCA (B). In (B), VP (or primary visits) indicate the serum collected from visit 1 to visit 5, while VT (or secondary visits) indicate the serum collected from visit 6 to visit 12. Compared to the control samples, GNEM patient-derived samples showed the upregulation of Krebs cycle intermediates, except for succinic acid (which was not found to be significant) and oxaloacetic acid, which was found to be downregulated in GNEM patients. Notably, the most significant altered TCA metabolite was malic acid, which was found to be upregulated in patients showing a p value < 0.001, when compared to control samples, at both the first and subsequent visits of the GNEM patients. * p value < 0.05; ** p value < 0.01; *** p value < 0.005; **** p value < 0.001; ns p value > 0.05.