Table 3.

Changes in metabolites associated with tyrosine and tryptophan metabolism in serum of the Placebo and the 600mg TT groups at 0 and 12 wk.

Sub pathway	Biochemical name	Placebo: Ratio 12 wk/0 wk	600mg TT: Ratio 12 wk/0 wk
Tyrosine	Tyrosine	1.03	0.92*
metabolism	n-Acetyltyrosine	1.03	0.82*
	4-Hydroxyphenylpyruvate	1.07	0.81*
	3-(4-hydroxyphenyl)lactate (HPLA)	1.16*	0.90*
	Vanillactate	1.39*	0.79
	p-Cresol-glucuronide	1.90*	1.72*
Tryptophan	n-acetyltryptophan	1.04	0.79*
metabolism	Kynurenine	1.00	0.88*
	3-indoxyl sulfate	1.15	1.28*
Nicotinate and nicotinamide metabolism	Quinolinate	0.94	0.81*

Metabolite values are expressed as the ratio of Placebo 12 wk/0 wk which is the fold change of the Placebo at 12 wk compared to the Placebo at 0 wk. Similarly, the ratio of 600mg TT 12 wk/0 wk which is the fold change of the 600mg TT at 12 wk compared to the High TT at 0 week. A ratio >1 indicates a value larger for the 12-wk collection (Placebo 12 wk or 600mg TT 12 wk) and <1 the value for the 12-wk collection (Placebo 12 wk or 600mg TT 12 wk) is lower compared to the 0-wk collection (Placebo 0 wk or 600mg TT 0 wk). Statistical differences are indicated for the values at baseline and after 12 weeks within the same treatment group or placebo (n = 20).

^*Indicates p < 0.05.