title: Apoptosis-related proteins are potential markers of neonatal hypoxic-ischemic encephalopathy (HIE) injury.
abstract: Neonatal hypoxic-ischemic encephalopathy (HIE) causes high mortality and long-term morbidity rates. The magnitude of the neuronal damage depends on the duration and severity of the initial insult combined with the deleterious effects of reperfusion and apoptosis. Currently, a diagnosis of HIE is based largely on the neurological and histological findings. Therefore, the aim of this study was to identify apoptosis-related proteins that might serve as potential markers of HIE injury. As an initial step toward reaching this objective, we analyzed changes in protein levels in an in vitro model of hypoxia using antibody arrays, and we have identified changes in the expression level of two proteins involved in apoptosis, Smac-DIABLO and cathepsin D. We obtained brain sections from eight neonatal HIE patients and performed histological staining, TUNEL assays and Smac-DIABLO and cathepsin D immunolocalization. Our results revealed a high number of TUNEL-positive cells, including neurons, astrocytes and ependymal cells, in the various regions that were analyzed. Interestingly, many of the areas that were positive for TUNEL staining did not appear to be damaged in the histological evaluation. In addition, using immunostaining, we found that Smac-DIABLO and cathepsin D had the same regional distribution pattern. Taken together, these findings indicate that these two proteins could serve as markers to identify injured regions that might not to be detectable using histological observations alone.
authors.affiliation: Servicio de Bioquímica-Investigación, Hospital Ramón y Cajal-IRYCIS, 28034 Madrid, Spain.
authors.forename: Macarena
authors.initials: M
authors.lastname: Hernández-Jiménez
authors.affiliation: Servicio de Neurobiología-Investigación, Hospital Ramón y Cajal-IRYCIS, 28034 Madrid, Spain.
authors.forename: Silvia
authors.initials: S
authors.lastname: Sacristán
authors.affiliation: Servicio de Anatomía Patológica, Hospital Universitario La Paz, 28046 Madrid, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Morales
authors.affiliation: Servicio de Anatomía Patológica, Hospital Ramón y Cajal-IRYCIS, 28034 Madrid, Spain.
authors.forename: Mercedes
authors.initials: M
authors.lastname: García-Villanueva
authors.affiliation: Servicio de Anatomía Patológica, Hospital Universitario La Paz, 28046 Madrid, Spain.
authors.forename: Eugenia
authors.initials: E
authors.lastname: García-Fernández
authors.affiliation: Servicio de Bioquímica-Investigación, Hospital Ramón y Cajal-IRYCIS, 28034 Madrid, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Alcázar
authors.affiliation: Servicio de Bioquímica-Investigación, Hospital Ramón y Cajal-IRYCIS, 28034 Madrid, Spain.
authors.forename: Víctor M
authors.initials: VM
authors.lastname: González
authors.affiliation: Servicio de Bioquímica-Investigación, Hospital Ramón y Cajal-IRYCIS, 28034 Madrid, Spain. Electronic address: m.elena.martin@hrc.es.
authors.forename: M Elena
authors.initials: ME
authors.lastname: Martín
mesh_terms: D000818:Animals; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins; D015415:Biomarkers / Q000378:metabolism; D001921:Brain / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism; D002402:Cathepsin D / Q000378:metabolism*; D015687:Cell Hypoxia; D005260:Female; D006801:Humans; D020925:Hypoxia-Ischemia, Brain / Q000378:metabolism*; D007223:Infant; D007231:Infant, Newborn; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D008297:Male; D024101:Mitochondrial Proteins / Q000378:metabolism*; D016716:PC12 Cells; D051381:Rats
chemical_list: D051017:Apoptosis Regulatory Proteins; D015415:Biomarkers; D002352:Carrier Proteins; C412403:DIABLO protein, human; C489013:DIABLO protein, rat; D047908:Intracellular Signaling Peptides and Proteins; D024101:Mitochondrial Proteins; D002402:Cathepsin D
keywords: Apoptosis; CTSD; Cathepsin D; HI; H–E; Neonatal hypoxia–ischemia; Smac (Second mitochondria-derived activator of caspase)-DIABLO (Direct Inhibitor of Apoptosis-Binding protein with LOw pI); Smac-DIABLO; cathepsin D; hematoxylin and eosin; hypoxia–ischemia