Table 3.

Impact and significance of arginine/proline metabolism, urea cycle, and bile-acid synthesis

Pathway	Metabolites in SMPD Pathway (m)	Metabolites Analyzed (m)	Pathway Impact	FDR-Adjusted P
Arginine and proline metabolism	53	15	0.21	5.8×10−4
Urea cycle	29	10	0.23	0.002
Bile-acid synthesis	65	12	0.01	0.005

For pathway-enrichment analyses, we used SMPD and included 34 metabolites that had a variable importance in projection score greater than one and P value <0.05. Global tests were used to assess the significance of pathways, and topology analysis with relative betweenness centrality was used to assess pathway impact. SMPD, Small Molecule Pathway Database; FDR, false discovery rate.