Figure legend
Fig 1. LC-MS/MS lipidomics analysis between the mild ICP and control group. (A) The score plot of the supervised orthogonal partial least squares discriminant analysis (OPLS-DA) of mild ICP (yellow) and control (red) group. (B) Permutation analysis. R2x (cum) and R2y (cum) represent the cumulative interpretation rate of the model in the x-axis and y-axis directions, respectively. Cum represents the accumulation of several principal components. Q2 (cum) represents the cumulative prediction rate of the model. (C) Volcano plots of the levels of differentially expressed lipids. Red indicates increased levels, blue indicates decreased levels, and gray indicates no statistical significance. (D) Hierarchical clustering of each sample data set showing the differentially expressed lipids.
Fig 2. LC-MS/MS lipidomics analysis between the severe ICP and control group. (A) The score plot of the OPLS-DA of severe ICP (blue) and control (red) group. (B) Permutation analysis. R2x (cum) and R2y (cum) represent the cumulative interpretation rate of the model in the x-axis and y-axis directions, respectively. Cum represents the accumulation of several principal components. Q2 (cum) represents the cumulative prediction rate of the model. (C) Volcano plots of the levels of differentially expressed lipids. Red indicates increased levels, blue indicates decreased levels, and gray indicates no statistical significance. (D) Hierarchical clustering of each sample data set showing the differentially expressed lipids.
Fig 3. Differentially expressed lipids in the mild and severe group and the pathway analysis. (A) Venn diagram of the differentially expressed lipids in ICP placenta and ICP plasma.(B) Pathway analysis of 44 differentially altered lipids.(C) Intensity of differential lipids expression in the control (blue), mild ICP (red) and severe ICP (green). Data are presented as the means ± SEMs. Significance was assessed using a two-tailed Student’s t-test. *P <0.05, **P <0.01, ***P <0.0001vs. the control group.
Fig 4. WGCNA analysis and identification of lipids associated with the clinical traits of ICP. (A) Pearson correlation analysis of the lipids module and clinical traits, the red color indicates a positive correlation and blue indicates negative correlation. The depth of the color indicates the strength of the correlation. (B) Hub lipids in pink module was screened out by CytoScape. (C) Intensity of differential hub lipids expression in the pink module. Data are presented as the means ± SEMs. Significance was assessed using a two-tailed Student’s t-test. **P <0.01, ***P <0.0001 vs. the control group.
Fig 5. Diagnostic utility of differential lipids in placenta from ICP pregnant women. (A) ROC analysis of SM (d42:1).(B) ROC analysis of SM (d18:1/24:1). (C) ROC analysis of PC (17:0/18:2). (D) ROC analysis of PE (16:0p/22:1).(E) ROC analysis of PE (18:0p/20:1). (F) ROC analysis of dMePE (20:1p/16:0). Multiple logistic regression analysis showed the combined ROC analysis of PE (16:0/20:2)/SM (d42:1)/PC (17:0/18:2)(G) and PE (16:0/20:2)/SM (d42:1)/PC (17:0/18:2)/PE (16:0p/22:1) (H) . AUC, area under the curve; CI, confidence interval; ROC, receiver operating characteristic.