INVESTIGADORES
CASTILLA LOZANO Maria Del Rocio
artículos
Título:
Neuroprotective effects of hypothermia on synaptic actin cytoskeletal changes induced by perinatal asphyxia.
Autor/es:
MUÑIZ, JAVIER; ROMERO, JUAN IGNACIO; HOLUBIEC, MARIANA; BARRETO, GEORGE; GONZALEZ, JANNET; SAINT MARTIN, MADELAINE; BLANCO, EDUARDO; CAVICCHIA, JUAN CARLOS; CASTILLA, ROCÍO; CAPANI, FRANCISCO
Revista:
BRAIN RESEARCH
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Atlanta; Año: 2014 vol. 1563 p. 81 - 90
ISSN:
0006-8993
Resumen:
Cerebral hypoxia-ischemia damages synaptic proteins, resulting in
cytoskeletal alterations, protein aggregation and neuronal death. In the
previous works, we have shown neuronal and synaptic changes in rat
neostriatum subjected to hypoxia that leads to ubi-protein accumulation.
Recently, we also showed that, changes in F-actin
organization could be related to early alterations induced by hypoxia
in the Central Nervous System. However, little is known about effective
treatment to diminish the damage. The main aim of this work is to study
the effects of birth hypothermia on the actin cytoskeleton of
neostriatal post-synaptic densities (PSD) in 60 days olds rats by
immunohistochemistry, photooxidation and western blot. We used 2
different protocols of hypothermia: (a) intrahypoxic hypothermia at 15°C
and (b) post-hypoxia hypothermia at 32°C. Consistent with previous data
at 30 days, staining with phalloidin-Alexa(488) followed by confocal
microscopy analysis showed an increase of F-actin
fluorescent staining in the neostriatum of hypoxic animals. Correlative
photooxidation electron microscopy confirmed these observations showing
an increment in the number of mushroom-shaped F-actin
staining spines in neostriatal excitatory synapses in rats subjected to
hypoxia. In addition, western blot revealed β-actin increase in PSDs in
hypoxic animals. The optic relative density measurement showed a
significant difference between controls and hypoxic animals. When
hypoxia was induced under hypothermic conditions, the changes observed
in actin cytoskeleton were blocked. Post-hypoxic hypothermia showed
similar answer but actin cytoskeleton modifications were not totally
reverted as we observed at 15°C. These data suggest that the decrease of
the body temperature decreases the actin modifications in dendritic
spines preventing the neuronal death.