Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We measured plasma neopterin at baseline and after oCRH and ACTH(1-24) stimulation tests in 35 unmedicated, adult major-depressive patients (mean age = 41 +/- 12 years) and in 35 normal control subjects individually matched to the patients. Neopterin is released by gamma-interferon-stimulated macrophages; because gamma-interferon is secreted by activated T-lymphocytes, elevated circulating neopterin is considered to reflect activation of the cell-mediated immune system. Plasma ACTH(1-39) and cortisol also were measured as indicators of pituitary-adrenal axis activity. Baseline plasma neopterin did not differ significantly between patients and controls (medians = 6.25 and 6.57 microg/l, respectively), but the baseline neopterin:creatinine ratio showed a trend toward lower values in the patients (P < 0.07). There was no apparent plasma neopterin change from baseline (area under the curve-AUC) following oCRH or ACTH(1-24) administration in either group of subjects. As with baseline neopterin, there was no significant patient-control difference in neopterin AUC following either hormone challenge, but there were trends toward lower neopterin:creatinine ratios in the patients following both challenges. In the patients, neither baseline neopterin nor neopterin AUCs following hormone challenge were significantly correlated with age, duration of depressive episode, lifetime number of episodes, melancholic subtype, Hamilton Depression Scale total score, Hamilton factor scores, or the Hamilton suicidality item score.
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PMID:Plasma neopterin in major depression: relationship to basal and stimulated pituitary-adrenal cortical axis function. 967 23

The symptom of intolerance to low levels of environmental chemicals (CI, chemical intolerance) is a feature of several controversial polysymptomatic conditions that overlap symptomatically with depression and somatization, i.e., chronic fatigue syndrome, fibromyalgia, multiple chemical sensitivity, and Persian Gulf syndrome. These syndromes can involve many somatic symptoms consistent with possible inflammation. Immunological or neurogenic triggering might account for such inflammation. Serum neopterin, which has an inverse relationship with l-tryptophan availability, may offer a marker of inflammation and macrophage/monocyte activation. This study compared middle-aged women with CI (who had high levels of affective distress; n = 14), depressives without CI (n = 10), and normals (n = 11). Groups did not differ in 4 p.m. resting levels of serum neopterin. However, the CI alone had strong positive correlations between neopterin and all of the scales measuring somatization. These preliminary findings suggest the need for additional research on biological correlates of 'unexplained' multiple somatic symptoms in subtypes of apparent somatizing disorders.
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PMID:Serum neopterin and somatization in women with chemical intolerance, depressives, and normals. 970 17

A phase I study to determine safety, maximum tolerated dose, and biologic response during multiple once-a-week administration of oral imiquimod, an immune response modifier, was conducted in 12 adults with early human immunodeficiency virus (HIV) infection. All completed the dose-escalation phase of weekly dosing at 100-mg increments and received at least one maintenance dose, 100 mg below the patient's toxic dose, for 12 weeks. Dose-limiting toxicity occurred in 3 patients at 200-mg, 5 at 300-mg, and 3 at 400-mg dose levels. One tolerated the 500-mg dose without dose-limiting toxicity. Dose-limiting toxicities included fatigue, fever, malaise, increased transaminases, hypotension, vomiting, and depression. Seven of 12 completed 12 weeks of maintenance. At > or = 200 mg of imiquimod, all patients had biologic responses, measured by elevations in serum interferon, beta2-microglobulin, and neopterin levels. Imiquimod induced pronounced levels of circulating interferon in asymptomatic HIV-infected persons, with variable effect on virus load.
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PMID:Administration of imiquimod, an interferon inducer, in asymptomatic human immunodeficiency virus-infected persons to determine safety and biologic response modification. 972 59

We have previously suggested that colorectal liver metastases might produce 'toxins' that reduce both quality of life (QoL) and survival. In this study we assessed whether QoL in patients with such metastases was related to immune activation, as determined by increased serum levels of interleukin 6 (IL6), soluble tumour necrosis factor receptor 1 (sTNFr1), soluble interleukin 2 receptor alpha (sIL2r alpha) or the interferon-gamma marker neopterin. Serum IL6, sTNFr1, sIL2r alpha, neopterin, alkaline phosphatase and carcinoembryonic antigen levels, liver metastasis volume, and QoL (Hospital Anxiety and Depression [HAD] scale, Rotterdam Symptom Checklist [RSC], and Sickness Impact Profile [SIP]) were measured in 43 patients. There were significant positive correlations between serum sIL2r alpha and HAD depression score (r = 0.66, P = 0.0001), RSC physical symptom score (r = 0.46, P < 0.01), and SIP score (r = 0.47, P = 0.009). Multiple regression analysis suggested that serum sIL2r alpha level was a significant independent predictor of HAD depression score. Although survival was shorter (logrank test P < 0.05) where sIL2r alpha, sTNFr1 and IL6 levels were higher, the ability of sIL2r alpha to predict HAD depression score was independent of survival.
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PMID:Relation between depression and circulating immune products in patients with advanced colorectal cancer. 981 54

Biopterin, neopterin and the large neutral amino acids (LNAA), i.e. phenylalanine, tyrosine, tryptophan, isoleucine, leucine and valine were measured in plasma of 20 severely depressed inpatients before and after a course of electroconvulsive therapy (ECT). These patients showed a significantly lower plasma biopterin concentration at baseline in comparison with healthy controls. After treatment an increase in biopterin was found, which was statistically significant in the depressed patients with psychotic features. The plasma phenylalanine-tyrosine ratio, which previously increased, normalised after ECT. Mean tryptophan concentration was lower in depressed patients than in normal controls. The patients who responded to ECT showed an increase in the tryptophan concentration and its ratio (tryptophan/LNAA) after treatment. Our results suggest that ECT increases biopterin, which probably results in synthesis of amino acids, especially tyrosine. Furthermore, ECT seems to increase cerebral tryptophan availability because of less tryptophan catabolism parallel with biopterin activation. More research is required to see if biopterin could be useful as a biological marker for the depressive state in this subgroup of patients, because this compound seems to play an important role in the etiology and treatment of depression.
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PMID:Effect of electroconvulsive therapy on biopterin and large neutral amino acids in severe, medication-resistant depression. 1154

The cytokine interferon-gamma stimulates human monocytes/macrophages to release large amounts of neopterin. Increased neopterin concentrations in body fluids of patients are observed during diseases with activated cellular (=TH1-type) immune response such as allograft rejection, virus infections, autoimmune disorders, or malignant tumors but also in neurodegenerative diseases or during pregnancy. In various cells interferon-gamma induces indoleamine 2,3-dioxygenase (IDO) which degrades tryptophan via the kynurenine pathway. Therefore like increased neopterin formation, enhanced tryptophan degradation is observed in diseases concomitant with cellular immune activation. Disturbed metabolism of tryptophan affects biosynthesis of neurotransmitter 5-hydroxytryptamine (serotonin), and it appears to be associated with an increased susceptibility for depression. In fact, enhanced neopterin concentrations together with increased degradation of tryptophan and low serum levels of tryptophan correlate with neuropsychiatric abnormalities like cognitive decline and depressive symptoms especially in long-lasting and chronic diseases. Activation of IDO could represent an important link between the immunological network and the pathogenesis of depression.
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PMID:Neopterin production, tryptophan degradation, and mental depression--what is the link? 1240 73

Immunotherapy with interferon-alpha (IFN-alpha) induces neuropsychiatric side effects, most notably depression. One of the presumed pathophysiological mechanisms is an effect on tryptophan metabolism. As tryptophan is the precursor of serotonin, decreased availability of tryptophan to the central nervous system could result in serotonin deficiency. Tetrahydrobiopterin (BH((4))) is a cofactor for one of the enzymes synthesizing serotonin. We conducted an exploratory study into the serum concentrations of large neutral amino acids (AA), biopterin (BIOP) and neopterin (NEOP), of 67 patients with high-risk melanoma, who were either treated with two different doses of IFN-alpha or were part of an observation-only control group. We found evidence for IFN-alpha to decrease concentrations of all AA except phenylalanine. The decrease in tryptophan concentration was most prominent and consistent. These changes persisted throughout a year of maintenance treatment. Concentrations of NEOP rose sharply, whereas, those of BIOP did not change. Except for the increase in NEOP and the increase in the ratio between phenylalanine (PHE) and tyrosine (TYR), no support for derangement in BH((4)) metabolism was found. The increase in the ratio between PHE and TYR suggests inhibition of the enzyme phenylalanine hydroxylase. Patients with IFN-alpha induced anxiety and depression had higher pretreatment concentrations of NEOP. Changes in tryptophan metabolism may play a role in the pathophysiology of the neuropsychiatric side effects of IFN-alpha, and further research into the predictive potential of NEOP is warranted.
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PMID:Serum amino acids, biopterin and neopterin during long-term immunotherapy with interferon-alpha in high-risk melanoma patients. 1286 Mar 66

In mice, activation of indoleamine-(2,3)-dioxygenase (IDO), an enzyme converting tryptophan to N-formyl-kynurenine, is required to achieve immunotolerance against the fetus and thus uncomplicated pregnancy. On the other hand, postpartum blues and depression appear to be related to reduced availability of tryptophan and serotonin. In healthy pregnant women with singleton pregnancies we consecutively analyzed kynurenine and tryptophan concentrations during pregnancy and postpartum. The kynurenine to tryptophan ratio (kyn/trp) was calculated as an estimate of IDO activity, and data were compared to concentrations of neopterin and 55kD soluble tumor necrosis factor receptor, two indicators of immune activation, and to alanineaminotransferase (ALT) levels. Increasing kynurenine and decreasing tryptophan concentrations were found during pregnancy. The data confirm earlier results and suggest significant degradation of tryptophan. In parallel, increasing concentrations of immune activation markers neopterin and sTNF-R55 were found, correlating significantly to the kyn/trp. The data point to an involvement of cytokine-induced IDO activation in the degradation of tryptophan observed during pregnancy. After pregnancy, sTNF-R55 and also neopterin concentrations declined, whereas tryptophan concentrations increased, indicating that immune activation and activation-induced tryptophan degradation has ceased. By contrast, still increased kynurenine concentrations and also increased kyn/trp suggest continuing turnover of tryptophan. Because also ALT was increased postpartum, abnormal activity of hepatic tryptophan pyrrolase and possibly other enzymes could be involved. We conclude that the decrease of tryptophan during pregnancy might be related to immune activation phenomena. Sustained increase of kynurenine postpartum seems independent from immune activation process, rather it seems related to abnormal activity of liver enzymes.
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PMID:Tryptophan degradation during and after gestation. 1520 18

Tetrahydrobiopterin is a cofactor in the synthesis of monoamine neurotransmitters. High neopterin levels generally signal increased immune activation. Both pterins have been investigated in several small clinical studies of depressed patients with conflicting results. Therefore, we examined the relation of plasma biopterin and neopterin with depression in a population-based study. We also studied the association of pterins with folates in depressed persons as this vitamin is required for pterin biosynthesis. We screened 3884 adults aged 60 years and over for depressive symptoms. Screen positive subjects had a psychiatric interview to diagnose DSM-IV disorder. Plasma pterins and serum folate were determined in all persons with depressive symptoms (n=238) and randomly selected non-depressed persons (n=357). We found no association between the concentration of biopterin or neopterin with depressive symptoms or depressive disorders. However, in depressed persons the relation between pterins and folates was different than in the non-depressed, i.e. neopterin concentrations increased with folate levels in persons with depressive symptoms (0.09 per log(nmol/l folate); 95% CI=0.01, 0.18, P=0.03), but not in non-depressed persons (-0.07 per log(nmol/l folate); 95% CI=-0.17, 0.03, P=0.18). The interaction between depressive symptoms, folate and neopterin was significant (P=0.03). The study suggests that the relation between folate and pterins is altered in the depressed elderly.
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PMID:Plasma pterins and folate in late life depression: the Rotterdam Study. 1707 Jun 3

Immunomodulatory therapy with interferon-alpha (IFN-alpha) often leads to neuropsychiatric side effects, especially depression. An activation of the immune system is discussed to trigger neurotransmitter changes and depressive illness. So far, few data are available about biologic markers, who may predict the individual risk for developing depressive symptoms during IFN-alpha therapy. The aim of the present study was to investigate the predictive role of certain immunologic markers for the development of IFN-alpha-induced depression. We hypothesized that patients characterized by a proinflammatory and TH1-accentuated immune response before treatment might have an increased risk for developing depressive mood changes. Thirty-three melanoma patients were prospectively investigated during adjuvant treatment with IFN-alpha-2a/2b (3 x 3 Mio units/wk). Depressive mood changes were assessed with the self-rating depression scale (SDS, Zung-scale) before and during IFN-alpha treatment. Serum concentrations of soluble tumor necrosis factor-R1 (sTNF-R1), soluble interleukin-6R (sIL-6R), sIL-4R, and neopterin were measured before and after 3 months of treatment. sIL-6R, which was negatively associated with SDS scores, significantly predicted higher depression scores in the first 3 months of IFN-alpha treatment. sTNF-R1, which was positively associated with SDS scores, significantly predicted the development of late depressive symptoms after 6 months of therapy. In contrast to the initial hypothesis, patients characterized by high sTNF-R1 and low sIL-6R baseline levels, indicating an anti-inflammatory condition before therapy, had a higher vulnerability for depression during IFN-alpha therapy.
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PMID:Pretreatment levels of sTNF-R1 and sIL-6R are associated with a higher vulnerability for IFN-alpha-induced depressive symptoms in patients with malignant melanoma. 1741 24


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