Abstract
Neonatal hypoxic-ischemic encephalopathy (HIE) remains a serious burden in neonatal care. Hypothermia provides a good outcome in some babies with HIE. Here, we investigated the biological mechanisms of its neuroprotective effect and sought for a new therapeutic target. We made neonatal HIE rats and subjected some of them to hypothermia at 28°C for 3 hours. We pathologically confirmed the efficacy of hypothermia against the neonatal HIE brain. To clarify the molecular mechanism of hypothermia's efficacy, we analyzed mRNA expression, immunoassay, and pathology in the brain with or without HIE and/or hypothermia. We selected from these analyses 12 molecules with possible neuroprotective effects. After identification of lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) as a therapeutic target candidate, we examined the efficacy of an anti-LOX-1 neutralizing antibody in neonatal HIE rats. Administration of an anti-LOX-1 neutralizing antibody reduced infarction area, brain edema, and apoptotic cell death to a degree comparable with hypothermia. Protection from those pathological conditions was considered part of the therapeutic mechanism of hypothermia. The efficacy of administering anti-LOX-1 neutralizing antibody was similar to that of hypothermia. LOX-1 is a promising therapeutic target in neonatal HIE, and the inhibition of LOX-1 may become a novel treatment for babies who have experienced asphyxia.