Background The aim of this cross-sectional study was to identify important biopsychosocial correlates of major depression. Biological mechanisms, including the inflammatory and the tryptophan-serotonin deficiency hypotheses of major depression, were investigated alongside health-related quality of life, life satisfaction, and social support. Methods The concentrations of plasma tryptophan, pl...

Kynurenic acid (KYNA), an astrocyte-derived, endogenous antagonist of α7 nicotinic acetylcholine and excitatory amino acid receptors, regulates glutamatergic, GABAergic, cholinergic and dopaminergic neurotransmission in several regions of the rodent brain. Synthesis of KYNA in the brain and elsewhere is generally attributed to the enzymatic conversion of L-kynurenine (L-KYN) by kynurenine amino...

Indoleamine 2,3-dioxygenase (IDO), a tryptophan-catabolizing intracellular enzyme of the L-kynurenine pathway, causes preneoplastic cells and tumor cells to escape the immune system by inducing immune tolerance; this mechanism might be associated with the development and progression of human malignancies. In the present study, we investigated the role of IDO in diethylnitrosamine (DEN)-induced ...

The two autonomously manifesting mutations, eyeless (el) and white eyes (wh), of Habrobracon juglandis were compared phenotypically with the wild-type. Eyeless reduces the compound eyes in size. The penetrance is 100%, while expressivity ranges from point-shaped ommochrome crumbs over individual facets to a small eye with abundant facets. There is no correlation between the sizes of left and ri...

This report describes the development of a simple, rapid method for the kinetic assay of tryptophan pyrrolase in Drosophila. By means of this method, one can readily make simultaneous measurements of tryptophan pyrrolase activity in as many as 36 samples. INTRODUCTION Tryptophan pyrrolase is essential in Drosophila for the formation of eye pigments. Vermilion eye mutants, for example, have low ...

The responses of female noninbred mouse urinary bladder ornithine decarboxylase (EC 4.1.1.17) (ODC) and S-adenosylu-methionine decarboxylase (EC 4.1.1.50) (SAMD) activities to L-tryptophan feeding and to topical intraurethral administration of L-tryptophan and some of its urinary metabolites were stud ied. Mice fed a diet containing 1% L-tryptophan demonstrated significant increases in vesical ...

The natural course of Chlamydia trachomatis urogenital tract infections varies between individuals. While protective immunity can occur, some women can become reinfected, contributing to the development of severe pathology. While the reasons for these differences are unknown, an individual's response to induced interferon-γ (IFN-γ) is suggested to be critical. IFN-γ induction of the enzyme indo...

The kynurenine pathway (KP) is the principal route of L-tryptophan (TRP) catabolism leading to the production of kynurenine (KYN), the neuroprotectants, kynurenic acid (KYNA) and picolinic acid (PIC), the excitotoxin, quinolinic acid (QUIN) and the essential pyridine nucleotide, nicotinamide adenine dinucleotide (NAD(+)). The enzymes indoleamine 2,3-dioxygenase-1 (IDO-1), indoleamine 2,3-dioxyg...

Successful long-term treatment of type-1 diabetes mainly relies on replacement of β-cells via islet transplantation. Donor shortage is one of the main obstacles preventing transplantation from becoming the treatment of choice. Although animal organs could be an alternative source for transplantation, common immunosuppressive treatments demonstrate low efficacy in preventing xenorejection. Immun...