Table 2. List of 32 Significantly Altered Metabolites between OA and RA SF (FDR < 0.05)^a.

metabolite	HMDB ref	higher in OA	higher in RA	fold change OA vs RA	–log10 (p-value)	FDR
2-Hydroxybutyrate	HMDB00008	Y		1.19	3.2495	1.70 × 10–3
3-Hydroxybutyrate	HMDB00357	Y		1.59	2.3288	1.02 × 10–2
3-Hydroxyisovalerate	HMDB00754	Y		2.22	7.6958	6.85 × 10–7
Acetate	HMDB00042		Y	–1.69	2.6401	5.56 × 10–3
Acetylcholine	HMDB00895	Y		1.57	3.9361	5.32 × 10–4
Acetylated-saccharide	None		Y	–1.49	4.5038	1.97 × 10–4
Adenosine	HMDB00050	Y		1.94	1.6375	4.45 × 10–2
Alanine	HMDB00161	Y		1.42	2.79	4.18 × 10–3
Asparagine	HMDB00168	Y		1.31	3.8413	5.83 × 10–4
Citrate	HMDB00094	Y		1.67	5.972	1.65 × 10–5
Creatinine	HMDB00562	Y		1.43	4.0608	4.48 × 10–4
Glucose	HMDB00122	Y		1.82	4.2582	3.03 × 10–4
Glutamine	HMDB00641	Y		1.80	9.7868	9.26 × 10–9
Glycerol	HMDB00131	Y		1.42	2.6897	5.18 × 10–3
Glycine	HMDB00123		Y	–1.64	3.9516	5.28 × 10–4
Guanidoacetate	HMDB00128	Y		1.19	3.283	1.61 × 10–3
Histidine	HMDB00177	Y		1.34	3.3713	1.36 × 10–3
Isoleucine	HMDB00172		Y	–1.39	4.0006	4.88 × 10–4
Leucine	HMDB00687		Y	–1.20	2.1407	1.52 × 10–2
Mannose	HMDB00169	Y		1.73	3.5567	9.85 × 10–4
Methionine	HMDB00696		Y	–1.30	2.8572	3.69 × 10–3
Mobile-lipid	None	Y		1.96	4.7317	1.42 × 10–4
Myoinositol	HMDB00211	Y		1.24	2.48	7.61 × 10–3
n-Acetylamino acid	None	Y		1.11	2.5075	7.24 × 10–3
Proline	HMDB00162	Y		1.26	3.1978	1.85 × 10–3
Pyruvate	HMDB00243	Y		3.44	11.994	8.61 × 10–11
Sarcosine	HMDB00271		Y	–1.56	4.6614	1.51 × 10–4
sn-Glycero-3-phosphocholine	HMDB00086	Y		1.49	3.0967	2.27 × 10–3
Taurine	HMDB00251	Y		1.26	2.2132	1.32 × 10–2
Threonine	HMDB00167		Y	–1.22	1.6233	4.50 × 10–2
Tyrosine	HMDB00158	Y		1.40	2.9942	2.78 × 10–3
Valine	HMDB00883	Y		1.25	2.5638	6.45 × 10–3

^aY = yes.