Here are the answers to the questions about pathway enrichment analysis:

1. What tool was used for pathway enrichment analysis?
MetaboAnalyst version 4.0 (Xia Lab, McGill University, Montreal, QC, Canada) was used for pathway analysis.

2. Was a tool version number provided?
Yes, the version number of MetaboAnalyst is 4.0.

3. What gene set library was queried (eg: GO, KEGG, Reactome or other)?
Not described.

4. Was a background gene list defined for pathway enrichment analysis?
Not described.

5. What statistical test was used for enrichment analysis?
Not described.

6. Was false discovery rate correction used to control the number of false positives in the pathway enrichment analysis?
Not described, but it is mentioned that FDR (False Discovery Rate) is an abbreviation in the article, however, its relation to pathway analysis is not explicitly stated. 

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