Table 3.

The altered metabolic pathways and the corresponding differential metabolites in AF samples from CON and GDM groups.

Pathway	Metabolites	p-Value	FC
Amino acids metabolism
Phenylalanine, tyrosine, and tryptophan biosynthesis	L-Phenylalanine	0.047	0.67
	L-Tyrosine	0.002	2.97
	3-Dehydroquinate	0.002	0.45
Phenylalanine metabolism	L-Phenylalanine	0.047	0.67
	L-Tyrosine	0.002	2.97
	Phenylacetylglutamine	0.022	0.53
	Phenylacetylglycine	0.050	0.36
	2-Hydroxycinnamic acid	<0.001	3.07
Cysteine and methionine metabolism	5’-Methylthioadenosine	0.002	0.66
	Homocysteine	0.001	11.46
	L-Methionine	0.008	2.61
Histidine metabolism	1-Methylhistamine	0.031	2.23
	Methylimidazole acetaldehyde	0.000	0.40
	3-Methylhistidine	0.037	0.37
D-Arginine and D-ornithine metabolism	D-Ornithine	0.015	0.67
Valine, leucine, and isoleucine biosynthesis	L-Valine	0.044	1.42
Tryptophan metabolism	5-Hydroxyindoleacetic acid	0.021	0.64
	L-Kynurenine	0.026	0.64
	Kynurenic acid	0.002	0.46
	5-Hydroxy-L-tryptophan	0.001	0.56
Lysine degradation	4-Trimethylammoniobutanal	0.028	0.65
Valine, leucine, and isoleucine degradation	L-Valine	0.044	1.42
Tyrosine metabolism	L-Tyrosine	0.002	2.97
	DL-Dopa		0.06
Carbohydrate metabolism
Starch and sucrose metabolism	Trehalose	<0.000	8.34
	D-Maltose	0.010	5.40
Amino sugar and nucleotide sugar metabolism	Glucosamine 6-phosphate	0.004	2.00
Galactose metabolism	myo-Inositol	0.000	0.40
	3’-Sialyllactose	0.000	18.10
	L-Galactose		12.95
Nucleotides metabolism
Aminoacyl-tRNA biosynthesis	L-Phenylalanine	0.047	0.67
	L-Methionine	0.008	2.61
	L-Valine	0.044	1.42
	L-Tyrosine	0.002	2.97
Purine metabolism	Adenine	0.000	0.44
Lipids metabolism
Glycerophospholipid metabolism	Glycerophosphocholine	0.022	1.77
	PS(18:0/22:6(4Z,7Z,10Z,13Z,16Z,19Z))	0.010	0.53
Vitamin metabolism
Nicotinate and nicotinamide metabolism	Niacinamide	0.003	0.35
	N1-Methyl-4-pyridone-3-carboxamide	<0.001	0.37
Vitamin B6 metabolism	Pyridoxal	0.042	1.57
Pantothenate and CoA biosynthesis	L-Valine	0.044	1.42
Choline	Trimethylamine N-oxide	0.031	3.64
Bile acid metabolism
Primary bile acid biosynthesis	Taurochenodesoxycholic acid	0.043	6.67
Others
Caffeine metabolism	Paraxanthine	<0.001	0.44

FC: Fold change was derived from normalized means of metabolites in GDM divided by that in CON.