. 2021 Jun 30;11(7):430. doi: 10.3390/metabo11070430

Table 5.

Metabolic signatures for asthma and its phenotypes.

Significant Metabolic Signatures		Population or Phenotype	Sample	AUC Values	Ref.
Carbohydrates
Glucose		A/H	serum, ↓		[177]
Glucose		O > L/ON	EBC		[193]
Monosaccharide		N > E > H	serum		[180]
Maltose		A/H	plasma, ↑		[182]
Maltotriose		A/H	plasma, ↑		[182]
D-Glyceric acid		O < L	serum		[184]
D-Glucoheptose 1		O > L	sputum		[184]
Amino acid Metabolism
Alanine		A/H	EBC, ↑		[191]
N-Methyl-DL-alanine		O > L	serum		[184]
Arginine		A/H	serum, ↓		[177]
Arginine		A/H	EBC, ↑		[191]
Glutamine		A/H	serum, ↑		[177]
L-glutamic acid		O > L	sputum		[184]
β-glutamic acid 1		O > L	sputum		[184]
Histidine		A/H	serum, ↓		[177]
Isoleucine		O < L	PBMCs		[184]
Isoleucine		A/H	EBC, ↑		[191]
Methionine		A/H	serum, ↑		[177]
Phenylalanine		A/H	EBC, ↑		[191]
Proline		A/H	EBC, ↑		[191]
Tyrosine		A/H	EBC, ↓		[191]
Tyrosine		O < L/ON	EBC		[193]
Valine		O > L	serum		[184]
Valine		A/H	EBC, ↓		[191]
Taurine		A/H	plasma, ↑		[182]
Gly-pro		O > L	sputum		[184]
5-Aminobaleric acid		A/H	serum, ↑	0.948	[178]
N,N-Dimethylglycine		A/H	EBC, ↑		[192]
3-Hydroxynorvaline 2		O < L	PBMCs		[184]
Lipid metabolism
Choline		A/H	serum, ↓		[177]
Glycerolipids	Phosphatidylcholine (20:4/16:1)	H > N > E	serum		[180]
	Phosphatidylcholine (18:1/2:0)	N > E > H	serum		[180]
	Phosphatidylcholine (16:0/18:1)	E > N > H	serum		[180]
	Acyl-alkyl-phosphatidylcholine (C42:4)	A/H	serum, ↑		[176]
	Acyl-alkyl-phosphatidylcholine (C42:5)	A/H	serum, ↑		[176]
	Acyl-alkyl-phosphatidylcholine (C44:5)	A/H	serum, ↑		[176]
	Acyl-alkyl-phosphatidylcholine (C44:6)	A/H	serum, ↑		[176]
	Phosphatidylethanolamine	A/H	plasma, ↑		[182]
	Phosphatidylethanolamine (38:1)	A/H	plasma, ↑	0.746	[183]
	Phosphatidylethanolamine (18:1p/22:6)	A/H	plasma, ↑	0.731	[183]
	Phosphatidylethanolamine (20:0/18:1)	A/H	plasma, ↑	0.710	[183]
	Phosphatidylethanolamine (18:3/14:0)	E > N > H	serum		[180]
	Phosphatidylglycerol (44:0)	A/H	plasma, ↓	0.675	[183]
	Glycerophosphorylcholine	A/H	plasma, ↑		[182]
		H > N > E	serum		[180]
	Β-glycerophosphorate	O > L	serum		[184]
	Lysophosphatidylcholine (18:1)	E > N > H	serum		[180]
	Lysophosphatidylcholine (22:4)	A/H	plasma, ↓	0.689	[183]
	Phosphatidylinositol	A/H	plasma, ↓	0.723	[183]
	Triglyceride (17:0/18:0/18:0)	A/H	plasma, ↑	0.714	[183]
	Triglyceride (16:0/16:0/18:1)	A/H	plasma, ↑	0.661	[183]
	O-phosphocholine	A/H	serum, ↓		[177]
Fatty acids	Saturated fatty acid	A/H	EBC, ↓		[191]
	Saturated fatty acid	O < L/ON	EBC		[193]
	Arachidonic acid	N > E > H	serum		[180]
	Arachidonate (20:4n6)	A/H	plasma, ↑		[182]
	Isobutyrate	A/H	EBC, ↑		[191]
	Linolenic acid	O < L	PBMCs		[184]
	N-palmitoyltaurine	SA	serum, ↓		[179]
	Oleamide	A/H	plasma, ↓		[182]
	n-valerate	O > L	EBC		[193]
	n-valerate	O < ON	EBC		[193]
	Isovalerate	O > L	EBC		[193]
Sphingolipids	Sphingosine	A/H	plasma, ↑		[182]
	Sphingosine-1-phosphate	SA	serum, ↑		[179]
	Sphingomyelin (d18:1/18:1)	A/H	plasma, ↑	0.731	[183]
	Phytosphingosine	H > N > E	serum		[180]
	Phytosphingosine 2	O > L	sputum		[184]
	Sphinganine	H > N > E	serum		[180]
	Ceramide (d16:0/27:2)	A/H	plasma, ↓	0.690	[183]
Eicosanoids	Leukotriene E₄	SA, T2	urine, ↑		[187]
	Tetranor prostaglandin D metabolites	SA, T2	urine, ↑		[187]
	2,3-dinor-11β-PGF_2α	SA, T2	urine, ↑		[187]
	8-iso-PGF_2α	SA	urine, ↑		[187]
	2,3-dinor-8-iso-PGF_2α	SA	urine, ↑		[187]
Sterol/Steroids	Androsterone sulfate	A/H	plasma, ↓		[182]
	Epiandrosterone sulfate	A/H	plasma, ↓		[182]
	Dehydroepiandrosterone sulfate	SA	serum, ↓		[179]
	Glycodeoxycholate	A/H	plasma, ↑		[182]
	Taurocholate	A/H	plasma, ↑		[182]
	Lathosterol	A/H	plasma, ↑		[182]
Retinol		H > N > E	serum		[180]
Carboxylic acid
Acetate		A/H	serum, ↓		[180]
		A/H	EBC, ↑/↓		[180]
		O < L/ON	EBC		[180]
Butyrate		A/H	EBC, ↑		[180]
Butyrate		O > ON	EBC		[180]
Formate		A/H	serum, ↓		[180]
		A/H	EBC, ↓		[180]
		O < L/ON	EBC		[180]
Propionate		A/H’	EBC, ↑		[180]
Propionate		O < L/ON	EBC		[180]
TCA cycle
Succinic acid		A/H	serum, ↑	0.976	[191]
Succinic acid		A/H	EBC, ↑/↓	0.976	[191]
Nucleoside/Nucleotide
Inosine		A/H	serum, ↑	0.962	[178]
Adenosine		A/H	EBC, ↓		[191]
Other organic compounds
Acetoin		O > L/ON	EBC		[193]
Alcohol	Ethanol	A/H	EBC, ↑		[191]
		O < L/ON	EBC		[193]
	Ethylene glycol	O < ON	EBC		[193]
	Isopropanol	A/H	EBC, ↑		[192]
	Methanol	A/H	serum, ↓		[177]
		A/H	EBC, ↑		[177]
		A/H	EBC, ↑		[191]
		O < L/ON	EBC		[191]
	1,2-propanediol	O > L	EBC		[193]
Amines	Trimethylamine	A/H	EBC, ↓		[191]
Ascorbate		A/H	serum, ↑	0.917	[178]
3-aminopropionitrile 1		O > L	sputum		[184]
Benzene	3,4-Dihydroxybenzoic acid	A/H	serum, ↑	0.965	[178]
Benzene	Hippurate	A/H	EBC, ↓		[191]
3-Hydroxybutyric acid		O > L	sputum		[184]
Ketones bodies	Acetone	A/H	serum, ↓		[177]
	Acetone	O < L	EBC		[193]
	2-Ketovaleric acid	A/H	serum, ↑	0.874	[178]
Lactate		O < L	EBC		[193]
Urocanic acid		A/H	EBC, ↓		[191]
Dehydroascorbic acid		A/H	serum, ↑	0.896	[178]
Urea		A/H	plasma, ↓		[182]
Urea		A/H	EBC, ↑		[192]
Uric acid		O > L	serum, ↑		[184]
Xanthine		O > L	sputum		[184]
Inorganic compounds
Ammonia		A/H	EBC, ↓		[192]
Pyrophosphate-3		O > L	sputum		[184]

A, asthmatics; H, healthy controls; O, obese asthmatics; L, lean asthmatics; ON, obese non-asthmatics; E, eosinophilic asthma; N, non-eosinophilic asthma; SA, severe asthma; T2, type 2 inflammation marker; ↓, lower in asthma; ↑, higher in asthma.