Molecule Report

Name	Tryptophan
Description	An essential amino acid that is necessary for normal growth in infants and for NITROGEN balance in adults. It is a precursor of INDOLE ALKALOIDS in plants. It is a precursor of SEROTONIN (hence its use as an antidepressant and sleep aid). It can be a precursor to NIACIN, albeit inefficiently, in mammals.
MeSH ID	D014364
No. of Studies (Positive/Negative)	13(13/0)

Name in Literature	Reference	Research Type	Statistical Result	Relation Description
tryptophan	Delgado, 1990	patients only		Fourteen of the 21 remitted depressed patients receiving ant...... Fourteen of the 21 remitted depressed patients receiving antidepressants experienced a depressive relapse after the tryptophan-free amino acid drink, with gradual (24 to 48 hours) return to the remitted state on return to regular food intake. More...
tryptophan	Kurup, 2002	patients and normal controls		There was increase in tyrosine and tyrosine catabolites, and...... There was increase in tyrosine and tyrosine catabolites, and a reduction in tryptophan and its catabolites, in the serum in the depressive phase of bipolar mood disorder and major depressive disorder. More...
tryptophan	Myint, 2007	patients and normal controls	P-value=0.036	The mean tryptophan breakdown index was higher (p=0.036), an...... The mean tryptophan breakdown index was higher (p=0.036), and mean kynurenic acid concentration and mean neuroprotective ratios were lower, in depressed patients (p=0.003 and 0.003, respectively). More...
tryptophan	Hughes MM, 2012	patients and normal controls		A depletion in tryptophan was evident in depressed patients ...... A depletion in tryptophan was evident in depressed patients and was correlated with HAM-D scores More...

Name in Literature	Related Components
	Level	Approved Name(Name in Literature)	Type	Reference	Research Type	Statistical Result	Relation Description	All
tryptophan		TPH1(TPH1)	gene	Porter RJ, 2008	patients only		There was an interaction between 218A>C and gender in determ...... There was an interaction between 218A>C and gender in determining plasma TRP whereby presence of the 218C allele, in women, was associated with markedly reduced plasma TRP. More...
tryptophan		Hydrocortisone(cortisol)	molecule	Price, 1998	patients only		The cortisol response to i.v. TRP (tryptophan) was significa...... The cortisol response to i.v. TRP (tryptophan) was significantly greater during TRP depletion than during sham depletion. More...
tryptophan		Serotonergic system(serotonergic (5-HT) system)	neurobiological system	Morris, 1999	patients only		Neural activity in several 5-HT-related brain areas, e.g., d...... Neural activity in several 5-HT-related brain areas, e.g., dorsal raphe, habenula, septal region, amygdala, and orbitofrontal cortex, covaried significantly with plasma levels of tryptophan. More...
tryptophan		Serotonergic system(serotonergic system)	neurobiological system	Klaassen, 2002	normal people		The influence of acute tryptophan (TRP) depletion, inducing ...... The influence of acute tryptophan (TRP) depletion, inducing low serotonin neurotransmission and a depression of mood. More...
tryptophan		Left amygdala(left amygdala)	brain morphology and function	Morris, 1999	patients only		Task-specific responses in left amygdala and left anterior c...... Task-specific responses in left amygdala and left anterior cingulate were attenuated by tryptophan depletion. More...
tryptophan		left anterior cingulate(left anterior cingulate)	brain morphology and function	Morris, 1999	patients only		Task-specific responses in left amygdala and left anterior c...... Task-specific responses in left amygdala and left anterior cingulate were attenuated by tryptophan depletion. More...
tryptophan		Anterior cingulate cortex(anterior cingulate cortices)	brain morphology and function	Neumeister, 2004	patients and normal controls		Compared with sham depletion, TD (tryptophan depletion) was ...... Compared with sham depletion, TD (tryptophan depletion) was associated with an increase in regional cerebral glucose utilization in the anterior cingulate cortices in patients with remitted MDD but not in controls. More...
tryptophan		medial thalamus(medial thalamus)	brain morphology and function	Neumeister, 2004	patients and normal controls		Compared with sham depletion, TD (tryptophan depletion) was ...... Compared with sham depletion, TD (tryptophan depletion) was associated with an increase in regional cerebral glucose utilization in the medial thalamus in patients with remitted MDD but not in controls. More...
tryptophan		Orbitofrontal cortex(orbitofrontal cortex)	brain morphology and function	Neumeister, 2004	patients and normal controls		Compared with sham depletion, TD (tryptophan depletion) was ...... Compared with sham depletion, TD (tryptophan depletion) was associated with an increase in regional cerebral glucose utilization in the orbitofrontal cortex in patients with remitted MDD but not in controls. More...
tryptophan		Posterior cingulate cortex(posterior cingulate cortices)	brain morphology and function	Neumeister, 2004	patients and normal controls		Compared with sham depletion, TD (tryptophan depletion) was ...... Compared with sham depletion, TD (tryptophan depletion) was associated with an increase in regional cerebral glucose utilization in the posterior cingulate cortices in patients with remitted MDD but not in controls. More...
tryptophan		Ventral striatum(ventral striatum)	brain morphology and function	Neumeister, 2004	patients and normal controls		Compared with sham depletion, TD (tryptophan depletion) was ...... Compared with sham depletion, TD (tryptophan depletion) was associated with an increase in regional cerebral glucose utilization in the ventral striatum in patients with remitted MDD but not in controls. More...
tryptophan		Caudate nucleus(caudate)	brain morphology and function	Roiser, 2009	patients and normal controls		Tryptophan depletion differentially affected the groups in t...... Tryptophan depletion differentially affected the groups in terms of hemodynamic responses to emotional words in a number of structures implicated in the pathophysiology of MDD, including caudate. More...
tryptophan		medial thalamus(medial thalamus)	brain morphology and function	Roiser, 2009	patients and normal controls		Tryptophan depletion differentially affected the groups in t...... Tryptophan depletion differentially affected the groups in terms of hemodynamic responses to emotional words in a number of structures implicated in the pathophysiology of MDD, including medial thalamus. More...
tryptophan		Cognitive processing bias(mood-congruent memory bias)	cognition and behavior	Klaassen, 2002	normal people		TRP (tryptophan) depletion impaired delayed recall of neutra...... TRP (tryptophan) depletion impaired delayed recall of neutral and positive words, but not of negative words. More...
tryptophan		Depressed mood(depressed mood)	symptoms	Delgado, 1990	patients only		Fourteen of the 21 remitted depressed patients receiving ant...... Fourteen of the 21 remitted depressed patients receiving antidepressants experienced a depressive relapse after the tryptophan-free amino acid drink, with gradual (24 to 48 hours) return to the remitted state on return to regular food intake. More...
tryptophan		Depressed mood(depressed mood)	symptoms	Delgado, 1994	patients only		Relative to the control test, 37% of the patients had 10-poi...... Relative to the control test, 37% of the patients had 10-point or greater decrease in Hamilton Depression Rating Scale (Ham-D) score, while 23% had a 10-point or greater increase in Ham-D score on the day after the tryptophan depletion test. More...
tryptophan		Depressed mood(depressed mood)	symptoms	Price, 1998	patients only		Depressive symptoms showed a tendency to decrease after i.v....... Depressive symptoms showed a tendency to decrease after i.v. TRP(tryptophan) following active, but not sham, TRP depletion. More...
tryptophan		Depressed mood(depressed mood)	symptoms	Klaassen, 1999	normal people		Overall, after 6 hours, TRP(tryptophan) depletion lead to a ...... Overall, after 6 hours, TRP(tryptophan) depletion lead to a lowering of mood. More...
tryptophan		Depressed mood(depressed mood)	symptoms	Klaassen, 2002	normal people		The influence of acute tryptophan (TRP) depletion, inducing ...... The influence of acute tryptophan (TRP) depletion, inducing low serotonin neurotransmission and a depression of mood. More...
tryptophan		Depressed mood(depressed mood)	symptoms	O'Reardon, 2004	patients only		The SSRI (selective serotonin re-uptake inhibitors) group ex...... The SSRI (selective serotonin re-uptake inhibitors) group experienced significant mood worsening during depletion compared with sham on both the HDRS (Hamilton Depression Rating Scale) and the BDI (Beck Depression Inventory), More...
tryptophan		Depressed mood(depressed mood)	symptoms	Neumeister, 2004	patients and normal controls	P-value<0.01	Tryptophan depletion induced a transient return of depressiv...... Tryptophan depletion induced a transient return of depressive symptoms in patients with remitted MDD but not in controls (P<.001). More...

---

Note:
1. The different color of the nodes denotes the level of the nodes.

Genetic/Epigenetic Locus	Protein and Other Molecule	Cell and Molecular Pathway	Neural System	Cognition and Behavior	Symptoms and Signs	Environment	MDD

2. User can drag the nodes to rearrange the layout of the network. Click the node will enter the report page of the node. Right-click will show also the menus to link to the report page of the node and remove the node and related edges. Hover the node will show the level of the node and hover the edge will show the evidence/description of the edge.
3. The network is generated using Cytoscape Web