Table 2

Serum differential metabolites among T2DM, T2DM+HBP and HC

Mode	Mass	Formula	RT	Metabolites	P value	T2DM versus HC	T2DM+HBP versus HC	T2DM+HBP versus T2DM
Positive electrospray ionization mode (ESI+)	129.045	C5 H7 N O3	1.11	Pyroglutamic acid	0.0083	↑	↑	↓
	131.094	C6 H13 N O2	3.73	L-isoleucine	0.0112	↓	↓	↓
	147.055	C5 H9 N O4	1.11	L-glutamic acid	0.0018	↑	↑	↓
	301.301	C18 H39 N O2	7.54	Sphinganine	<0.0001	↓	↑	↑
	539.529	C34 H69 N O3	10.11	Cer(d18:0/16:0)	<0.0001	↓	↓	↑
	567.56	C36 H73 N O3	10.83	Cer(d18:0/18:0)	0.0027	↓	↓	↑
Negative electrospray ionization mode (ESI−)	129.043	C5 H7 N O3	1.55	Pyroglutamic acid	<0.0001	↑	↑	↓
	192.028	C6 H8 O7	1.42	Citric acid	0.0003	↑	↑	↑
	280.22	C18 H32 O2	9.76	Linoleic acid	0.0046	↑	↑	↓

The symbol ↑: rising tendency; the symbol ↓: downtrend.
ESI, electrospray ionization; HBP, high blood pressure; HC, healthy control; T2DM, type 2 diabetes mellitus.