Full text
| |
| Author(s): |
Ariane Rivellis Julio
Total Authors: 1
|
| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Conjunto das Químicas (IQ e FCF) (CQ/DBDCQ) |
| Defense date: | 2016-02-19 |
| Examining board members: |
Ernani Pinto Junior;
Valdemir Melechco Carvalho;
Jair Ribeiro Chagas;
Eduardo Purgatto
|
| Advisor: | Ernani Pinto Junior; Ana Campa |
| Abstract | |
The tryptophan metabolism (Trp) takes place by means of kynurenine (QUIN), by the serotonin pathway (SER) and by the pathway of trace amines synthesis. The first generates QUIN and a variety of other secondary metabolites. When driven by the enzyme indoleamine 2,3 dioxygenase (IDO) contributes to the phenomena of tolerance and immune escape of tumor cells; and when conducted by tryptophan 2,3 -dioxygenase (TDO) in the liver, participates in the niacin synthesis NAD. The SER pathway leads to the serotonin neurotransmitter (SER) formation, which can generate the hormone melatonin (MEL), respectively and other biologically active metabolites. Another less studied amines trace synthesis pathway produces neuroactive products. Given the scope and importance of Trp metabolic pathways,we developed and validated a robust, sensitive and selective bioanalytical method by high performance liquid chromatography (HPLC) coupled mass spectrometry (MS) for simultaneous determination of TRP and its 16 metabolites. Therefore, we chose to evaluate the three routes, glioma cell lines. The initial choice of this type of cell was due to the great interest in Trp metabolism studies in tumor cells, which glioma cells has been a model. In assays with glioma cells, we followed the effects of an inductor and inhibitors of the first stage of Trp metabolism, via the kynurenine pathway, or IFN -γ (IDO inducer) 1- methyltryptophane (1- MT; competitive IDO inhibitor) and 680C91 (selective TDO inhibitor). We could observe the first step induction or inhibition impact had over the further metabolites and the metabolism differences between the two studied strains, A172 and T98G. The T98G glioma cell has only IDO activity, while the A172 has both IDO and TDO activity as well. The IFN-γ indution showed that this cytokine not only acts in the formation of QUIN route, but has a modest impact on the others routes. Inhibition of IDO showed that the competitive inhibitor has activity in itself than a simple Trp-QUIN relationship. However, our results allow us to show the first time the complete description of these pathways, in particular, in these cell lines that can assume therapeutic strategies in these routes that are related or not with tumor progression. (AU) | |
| FAPESP's process: | 12/00764-8 - Development and validation of bioanalytical methods for monitoring the products of metabolic pathways of tryptophan in human glioma cell line |
| Grantee: | Ariane Rivellis Júlio |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |