. 2014 Jun 11;9(6):e96969. doi: 10.1371/journal.pone.0096969

Table 2. OPLS-DA coefficients and their variable importance in projection (VIP) for significantly changed metabolites in urine.

Metabolites			Multi-criteria assessment (MCA)^a
No.	Names	δ ¹H (ppm)	HFD vs. Normal			HFD+GAH vs. HFD
			Coefficient value^b	VIP	p value^c	Coefficient value^b	VIP	p value^c
14	Acetate	1.92 (s)	0.662	1.50	–, 0.080	0.594	1.30	↑, 0.044
20	Acetoacetate	2.29 (s)	−0.920	1.38	↓, <0.001	0.519	1.75	↑, 0.040
21	Pyruvate	2.37 (s)	0.863	1.98	↑, <0.001	0.020	0.34	–, 0.801
22	Succinate	2.41 (s)	−0.842	2.43	↓, <0.001	0.653	3.36	–, 0.081
23	Citrate	2.69 (d)	−0.701	3.70	↓, 0.005	0.681	2.48	–, 0.970
26	Creatine	3.93 (s)	−0.750	3.32	↓, 0.001	0.076	1.38	–, 0.564
27	Creatinine	3.05 (s)	0.938	4.14	↑, <0.001	0.641	3.31	↑, 0.048
31	Taurine	3.27 (t)	0.639	3.07	↑, 0.006	−0.653	7.55	↓, 0.019
35	Glycine	3.55 (s)	0.738	2.07	↑, 0.001	−0.312	1.61	–, 0.222
37	Formate	8.46 (s)	0.909	0.42	↑,<0.001	−0.396	0.32	–, 0.179
43	Butyrate	0.90 (t)	0.619	1.90	↑, 0.001	0.311	1.65	–, 0.063
50	2-oxoglutaric acid (2-KG)	2.44 (t)	−0.782	1.66	↓, 0.001	0.267	0.19	–, 0.787
52	Dimethylamine (DMA)	2.72 (s)	−0.412	0.80	–, 0.089	−0.472	1.89	↓, 0.041
53	Trimethylamine (TMA)	2.89 (s)	−0.915	8.43	↓, <0.001	−0.566	5.56	↓, 0.031
57	Guanidoacetate	3.80 (s)	0.951	2.74	↑, <0.001	−0.363	1.61	–, 0.236
58	Trans-aconitate	6.59 (s)	−0.872	1.13	↓, <0.001	0.203	0.12	–, 0.684
60	Glucose (α & β form)	3.90 (dd)	0.835	1.73	↑, <0.001	−0.588	2.40	↓, 0.013
61	Hippurate	7.64 (t)	−0.970	1.58	↓, <0.001	0.516	0.56	↑, 0.035
62	Trigonelline	8.84 (t)	−0.951	0.64	↓, <0.001	0.449	0.30	–, 0.129
63	1-Methylnicotinamide	8.90 (d)	0.975	0.67	↑, <0.001	−0.330	0.42	–, 0.137
70	Nicotinamide N-oxide	8.49 (d)	0.573	0.23	↑, <0.001	−0.549	0.54	–, 0.261
73	Niacinamide	8.94 (d)	−0.635	0.22	↓, 0.005	0.355	0.09	–, 0.543

Multi-criteria assessment (MCA) was performed using the followed criteria: 1. Coefficient value |r| >0.576, 2. VIP>1, 3. p value <0.05.

Coefficient values were calculated using NOESY coefficient-coded loadings plots. The coefficients from the OPLS-DA results; positive and negative signs indicate positive and negative correlations in the concentrations of serum metabolites.

Independent t test (two-tailed).