Table 1.

13 biomarkers of hyperlipidemia detected by UPLC Q-TOF/MS in negative ion mode in the 4th week.

Number	Mass	Metabolite	i-FITa, elemental composition	Molecular weight	Formula	Trendb	Related pathway
1	284.2934	Octadecanamide	0.9, C18H38NO	283.4925	C18H37NO	↑**	Fatty acid metabolism
2	282.2779	Oleamide	1.2, C18H36NO	281.2718	C18H35NO	↑**	Fatty acid metabolism
3	188.0713	Tryptophan	0.9, C11H10N1O2	204.2252	C11H12N2O2	↑**	Amino acid metabolism
4	193.1235	Citric acid	0.7, C6H9O7	192.1243	C6H8O7	↓**	TCA cycle
5	330.0618	Adenosine 2′,3′-cyclic phosphate	1.0, C10H13N5O6P	329.2059	C10H12N5O6P	↓**	Purine metabolism
6	393.3002	Ursodeoxycholic acid	0.8, C24H41O4	392.5720	C24H40O4	↑**	Bile acid metabolism
7	114.0641	Creatinine	1.2, C4H8N3O	113.1179	C4H7N3O	↑**	Energy metabolism
8	281.0979	Ascorbalamic acid	0.9, C9H17N2O8	263.2014	C9H13NO8	↑**	Carbohydrate metabolism
9	259.0913	3-Methyluridine	1.2, C10H15N2O6	258.228	C10H14N2O6	↑**	Nucleoside metabolism
10	212.1025	3-O-Methyldopa	1.7, C10H14NO4	211.2145	C10H13NO4	↓**	Amino acid metabolism
11	162.1108	Proline	0.7, C7H13O3	115.1305	C7H12O3	↓**	Amino acid metabolism
12	282.1216	1-Methyladenosine	1.2, C11H16N5O4	281.2679	C11H15N5O4	↓**	Nucleoside metabolism
13	162.0538	Indole-3-carboxylic acid	0.8, C9H8NO2	161.1574	C9H7NO2	↑**	Amino acid metabolism
14	368.1594	Tryptophyl-tyrosine	1.2, C20H22N3O4	367.3984	C20H21N3O4	↑**	Amino acid metabolism
15	166.0708	Phenylalanine	0.9, C9H12NO2	165.1891	C9H11NO2	↓**	Amino acid metabolism
16	126.0643	5-Methylcytosine	1.3, C5H8N3O	125.1286	C5H7N3O	↓**	Nucleoside metabolism

^ai-FIT; the i-FIT is the correctness of isotope patterns of elemental composition. The lower i-FIT normalized values mean high precision of the elemental composition; ^bchange trend of hyperlipidemia rats versus control rats. The potential biomarkers were labeled with (↓) downregulated and (↑) upregulated. *P < 0.05 and **P < 0.01.