Table 2.

Linear regression analyses of microbiome-related and linoleic acid-related plasma metabolites (dependent variable) related to bone turnover markers (independent variable).

Plasma Metabolite	m/z	Time (s)	β Estimate ± SE	p-Value
Associations with P1NP
Tryptophan	205.0971	36	−0.03 ± 0.02	0.07
3-Hydroxykynurenine	225.0823	33	−0.02 ± 0.05	0.76
L-Kynurenine	209.092	40	−0.05 ± 0.03	0.06
Indole	118.0652	38	−0.03 ± 0.02	0.11
Indole-3-Acetaldehyde	160.0798	90	0.04 ± 0.02	0.01
5-Hydroxyindoleacetate	192.0655	38	–0.08 ± 0.05	0.09
Indole-3-Ethanol	162.0955	57	0.08 ± 0.05	0.14
3-Methyl-2-Oxindole	148.0732	248	0.16 ± 0.08	0.04
Indole-3-Acetic Acid	176.0705	24	–0.1 ± 0.07	0.17
Methyl Indole-3-Acetate	190.0845	153	–0.14 ± 0.11	0.20
Phenylacetic Acid	137.0551	68	0.03 ± 0.04	0.40
Linoleic Acid (FA 18:2)	281.2475	199	0.01 ± 0.08	0.90
HPODE	313.2373	259	–0.01 ± 0.05	0.80
HODE/EpOME	297.2211	221	–0.03 ± 0.04	0.50
Associations with CTX
Tryptophan	205.0971	36	0.02 ± 0.24	0.93
3-Hydroxykynurenine	225.0823	33	–0.56 ± 0.7	0.43
L-Kynurenine	209.092	40	0.37 ± 0.38	0.33
Indole	118.0652	38	0.22 ± 0.24	0.36
Indole-3-Acetaldehyde	160.0798	90	0.36 ± 0.25	0.16
5-Hydroxyindoleacetate	192.0655	38	0.47 ± 0.66	0.48
Indole-3-Ethanol	162.0955	57	1.47 ± 0.68	0.04
3-Methyl-2-Oxindole	148.0732	248	1.48 ± 0.45	0.58
Indole-3-Acetic Acid	176.0705	24	0.0001 ± 0.99	1.00
Methyl Indole-3-Acetate	190.0845	153	0.65 ± 1.16	0.33
Phenylacetic Acid	137.0551	68	1.02 ± 0.48	0.04
Linoleic Acid (FA 18:2)	281.2475	199	1.88 ± 1.04	0.08
HPODE	313.2373	259	0.64 ± 0.64	0.33
HODE/EpOME	297.2211	221	0.64 ± 0.6	0.29

Bolded p-values indicate significant findings at p < 0.05. All metabolites were matched to positive ions and have a level 1 metabolite identification confidence score. Abbreviations: m/z, mass-to-charge ratio; SE, standard error; HPODE, hydroperoxy-octadecadienoic acid; EpOME, epoxyoctadecenoic acid (a peroxidation product of linoleic acid); HODE, hydroxyoctadecadienoic acid (a derivative of linoleic acid).