In vitro Metabolic Studies of Dopamine Synthesis and the Toxicity of L-DOPA in Human Cells

Delcambre, Sylvie

Reference : In vitro Metabolic Studies of Dopamine Synthesis and the Toxicity of L-DOPA in Human Cells


	Document type :	Dissertations and theses : Doctoral thesis
	Discipline(s) :	Life sciences : Biochemistry, biophysics & molecular biology
	Focus Areas :	Systems Biomedicine
	To cite this reference:	http://hdl.handle.net/10993/28204

Title :	In vitro Metabolic Studies of Dopamine Synthesis and the Toxicity of L-DOPA in Human Cells
Language :	English
Author, co-author :	Delcambre, Sylvie [University of Luxembourg > Luxembourg Centre for Systems Biomedicine (LCSB) > >]
Publication date :	15-Jul-2016
Institution :	University of Luxembourg, Esch sur Alzette, Luxembourg
Name of the degree :	PhD
Number of pages :	207
Supervisor :	Hiller, Karsten
President of the jury :	Haan, Serge
Member of the jury :	Leist, Marcel
	Linster, Carole
	Marcus, Katrin
Keywords :	[en] Dopamine ; Metabolism ; Neurons
Abstract :	[en] This work is divided in two parts. In the first, I investigated the effects of 2,3- dihydroxy-L-phenylalanine (L-DOPA) on the metabolism of human tyrosine hydroxylase (TH)-positive neuronal LUHMES cells. L-DOPA is the gold standard treatment for Parkinson’s disease (PD) and its effects on cellular metabolism are controversial. It induced a re-routing of intracellular carbon supplies. While glutamine contribution to tricarboxylic acid (TCA) cycle intermediates increased, glucose contribution to the same metabolites decreased. Carbon contribution from glucose was decreased in lactate and was compensated by an increased pyruvate contribution. Pyruvate reacted with hydrogen peroxide generated during the auto-oxidation of L-DOPA and lead to an increase of acetate in the medium. In the presence of L-DOPA, this acetate was taken up by the cells. In combination with an increased glutamate secretion, all these results seem to point towards a mitochondrial complex II inhibition. In the second part of this work, I studied and compared dopamine (DA)-producing in vitro systems. First, I compared gene and protein expression of catecholamine (CA)- related genes. Then, I performed molecular engineering to increase TH expression in LUHMES and SH-SY5Y cells. This was sufficient to induce DA production in SH-SY5Y, but not in LUHMES cells, indicating that TH expression is not sufficient to characterize dopaminergic neurons. Therefore I used SH-SY5Y cells overexpressing TH to study substrates for DA production. Upon overexpression of aromatic amino acid decarboxylase (AADC), LUHMES cells produced DA after L-DOPA supplementation. This model was useful to study L-DOPA uptake in LUHMES cells and I showed that L-DOPA is imported via large amino acid transporter (LAT). In conclusion, the expression of TH is not sufficient to obtain a DA-producing cell system and this work opened many and answered some questions about DA metabolism.
Research centres :	Luxembourg Centre for Systems Biomedicine (LCSB): Metabolomics (Hiller Group)
Funders :	Aide à la Formation Recherche PhD (FNR)
Target :	Researchers ; Professionals ; Students
Permalink :	http://hdl.handle.net/10993/28204

File(s) associated to this reference

Fulltext file(s):

	File	Commentary	Version	Size	Access
Open access	DELCAMBRE_Thesis_main_final.pdf		Author postprint	12.62 MB	View/Open

All documents in ORBi^lu are protected by a user license.

University of Luxembourg Library | Feedback | Legal notices