Table 1.

Effects of aging and TB supplementation on the butyrate synthesizing potential of gut microbiota in 3×Tg mice.

Gene	Enzyme name	Butyrate Synthesis Pathway	2mo vs. 12mo		2mo vs. 18mo		12mo vs. 18mo		18mo vs. 18mo+TB
			Trend	p-value	Trend	p-value	Trend	p-value	Trend	p-value
puuE or GABA-T	4-aminobutyrate transaminase	4-Aminobutyrate	↓	n.s.	↓	0.023	↓	n.s.	↑	n.s.
4Hbt, cat2, or abfT	butyryl-CoA:4-hydroxybutyrate CoA transferase	Acetyl-CoA	↓	0.055	↓	0.052	↓	n.s.	↑	0.070
phbB	acetoacetyl-CoA reductase	Acetyl-CoA	↓	n.s.	↓	n.s.	↓	0.012	↑	0.049
atoB	thiolase	Acetyl-CoA	↓	0.039	↓	0.032	↓	n.s.	↑	n.s.
ptb	phosphate butyryltransferase	Acetyl-CoA	↓	n.s.	↓	0.051	↓	n.s.	↑	n.s.
buk	butyrate kinase	Acetyl-CoA	↓	0.062	↓	0.037	↓	n.s.	↑	n.s.
crt	crotonase	Acetyl-CoA	↓	0.045	↓	0.039	↓	n.s.	↑	0.061
gctA	glutaconate CoA transferase α	Glutarate	↓	0.041	↓	0.042	↓	n.s.	↑	n.s.
gctB	glutaconate CoA transferase β	Glutarate	↓	0.037	↓	0.038	↓	n.s.	↑	n.s.
kamA	lysine-2.3-aminomutase	Lysine	↓	0.049	↓	0.031	↓	n.s.	↑	n.s.
bcd	butyrate-CoA dehydrogenase (including electron transfer protein α, β subunits)	Common to all	↓	0.047	↓	0.039	↓	n.s.	↑	n.s.
estA	esterase	putative tributyrin esterase	↓	0.036	↓	0.024	↓	n.s.	↑	0.030

Results from Kruskal–Wallis test comparing the abundance of butyrate synthesizing genes in cecal samples of 3×Tg mice at 2, 12 and 18 months of age. TB: tributyrin; n.s.: no significance. Enzyme abbreviations defined in legend for Figure 3.