Content and traffic of taurine in hippocampal reactive astrocytes.
Taurine is one of the most abundant free amino acids in the mammalian central nervous system, where it is crucial to proper development. Moreover, taurine acts as a neuroprotectant in various diseases; in epilepsy, for example, it has the capacity to reduce or abolish seizures. In the present study, taurine levels has been determine in mice treated with Kainic Acid (KA) and results showed an increase of this amino acid in hippocampus but not in whole brain after 3 and 7 days of KA treatment. This increase occurs when gliosis was observed. Moreover, taurine transporter (TAUT) was found in astrocytes 3 and 7 days after KA treatment, together with an increase in cysteine sulfinic acid decarboxylase (csd) mRNA, that codifies for the rate-limiting enzyme of taurine synthesis, in the hippocampus at the same times after KA treatment. Glial cultures enriched in astrocytes were developed to demonstrate that these cells are responsible for changes in taurine levels after an injury to the brain. The cultures were treated with proinflammatory cytokines to reproduce gliosis. In this experimental model, an increase in the immunoreactivity of GFAP was observed, together with an increase in CSD and taurine levels. Moreover, an alteration in the taurine uptake-release kinetics was detected in glial cells treated with cytokine. All data obtained indicate that astrocytes could play a key role in taurine level changes induced by neuronal damage. More studies are, therefore, needed to clarify the role taurine has in relation to neuronal death and repair.
Junyent
Fèlix
F
Unitat de Farmacologia i Farmacognòsia Facultat de Farmàcia, Institut de Biomedicina (IBUB), Centros de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Universitat de Barcelona, Spain. felixjunyent@ub.edu
De Lemos
Luisa
L
Utrera
Juana
J
Paco
Sonia
S
Aguado
Fernando
F
Camins
Antoni
A
Pallàs
Mercè
M
Romero
Rafael
R
Auladell
Carme
C
D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000378:metabolism*; D001483:Base Sequence; D001693:Biological Transport, Active / Q000187:drug effects; D002262:Carboxy-Lyases / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D016207:Cytokines / Q000494:pharmacology; D017931:DNA Primers / Q000235:genetics; D005904:Glial Fibrillary Acidic Protein; D005911:Gliosis / Q000139:chemically induced / Q000378:metabolism; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D018836:Inflammation Mediators / Q000494:pharmacology; D007608:Kainic Acid / Q000633:toxicity; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D009419:Nerve Tissue Proteins / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013654:Taurine / Q000378:metabolism*; D000099247:Taurine Transporters
D002262:Carboxy-Lyases; D016207:Cytokines; D017931:DNA Primers; D005904:Glial Fibrillary Acidic Protein; D018836:Inflammation Mediators; D007608:Kainic Acid; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D013654:Taurine; D000099247:Taurine Transporters; C528900:glial fibrillary astrocytic protein, mouse; C019972:sulfoalanine decarboxylase