Fig 1: Exercise training differentially alters the serine-sphingolipid muscle metabolite networks in diet-sensitive and diet-resistant women with obesity. (a-e) Enriched metabolite networks reveal differing profiles in vastus lateralis from DR and DS individuals at BL and PET. (a) The correlation network for plasma serine. Shown are partners with distance correlation > 0.7; P<0.02, (n=10). (b) Selection of the most significantly different sphingolipid features in vastus lateralis. Shown are features with ReliefF weight measure over 0.03 (major contributors to a classification model), (n=5). (C) Immunoblot analyses revealed relative protein expression of SPTLC1 did not differ between DR and DS, whereas expression of SPTLC2 was lower in DR skeletal muscle following exercise training. (*P<0.05, Two-way ANOVA for repeated-measures with Holm-Sidak post hoc test, n=9). (d) Heatmap clustering of relative sphingolipid level changes compared to the total sample mean in the DS and DR groups before and after exercise. Data were log-transformed and z-scored. (e) Sphingolipid metabolic pathway indicating network correlations are distinct in DR and DS groups at baseline. Direction of arrows indicates direction of correlation; arrow colours indicate correlations between sphingolipid species at the beginning (serine) or end (O-phosphorylethanolamine (PE)) of the sphingolipid metabolic pathway in either the DR or DS groups. The number of species with significant correlations in each subclass (absolute correlation level over 0.6 with P<0.05) are indicated. Data in bar graphs represent mean ± SEM. (*P< 0.05, t-test with Welch's correction, n=5). See also Figure S4.