Biomarkers for severity of neonatal hypoxic-ischemic encephalopathy and outcomes in newborns receiving hypothermia therapy

UCH-L1 and GFAP Serum Levels in Neonates with Hypoxic-Ischemic Encephalopathy: A Single Center Pilot Study

Objective: We examined two potential biomarkers of brain damage in hypoxic–ischemic encephalopathy (HIE) neonates: glial fibrillary acidic protein (GFAP; a marker of gliosis) and ubiquitin C-terminal hydrolase L1 (UCH-L1; a marker of neuronal injury). We hypothesized that the biomarkers would be measurable in cord blood of healthy neonates and could serve as a normative reference for brain injury in HIE infants. We further hypothesized that higher levels would be detected in serum samples of HIE neonates and would correlate with brain damage on magnetic resonance imaging (MRI) and later developmental outcomes.?

Study Design: Serum UCH-L1 and GFAP concentrations from HIE neonates (n = 16) were compared to controls (n = 11). The relationship between biomarker concentrations of HIE neonates and brain damage (MRI) and developmental outcomes (Bayley-III) was examined using Pearson correlation coefficients and a mixed model design.

Result: Both biomarkers were detectable in cord blood from control subjects. UCH-L1 concentrations were higher in HIE neonates (p < 0.001), and associated with cortical injury (p < 0.055) and later motor and cognitive developmental outcomes (p < 0.05). The temporal change in GFAP concentrations during (from birth to 96 h of age) predicted motor developmental outcomes (p < 0.05) and injury to the basal ganglia and white matter.

Conclusion: Ubiquitin C-terminal hydrolase L1 and GFAP should be explored further as promising serum biomarkers of brain damage and later neurodevelopmental outcomes in neonates with HIE.

Serum biomarkers to evaluate the integrity of the neurovascular unit

Biomarkers have the potential to enable the clinicians to screen infants for brain injury, monitor progression of disease, identify injured brain regions, assess efficacy of neuroprotective therapies, and offer hope to identify the timing of the injury, thus shedding light on the potential pathophysiology and the most effective therapy. Currently, clinicians do not routinely use biomarkers to care for neonates with Neonatal Encephalopathy (NE) and brain injury due to prenatal hypoxia-asphyxia. This review will cover potential biomarkers of the neurovascular unit in the setting of NE that (i) can help assess the degree or severity of encephalopathy at birth; (ii) can help monitor progression of disease process and efficacy of neuroprotective therapy; (iii) can help assess neurodevelopmental outcome. These biomarkers will be summarized in two categories: 1) Specific biomarkers targeting the neurovascular unit such as glial fibrillary acidic protein (GFAP), ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1), S100B, and neuron specific enolase (NSE) and 2) general inflammatory cytokines, such as interleukin-6 (IL-6), interleukin-1b (IL-1b), and pNF-H, among others.

Inflammatory injury to the neonatal brain - what can we do?

Perinatal brain damage is one of the leading causes of life long disability. This damage could be hypoxic-ischemic, inflammatory, or both. This mini-review discusses different interventions aiming at minimizing inflammatory processes in the neonatal brain, both before and after insult. Current options of anti-inflammatory measures for neonates remain quite limited. We describe current anti-inflammatory intervention strategies such as avoiding perinatal infection and inflammation, and reducing exposure to inflammatory processes. We describe the known effects of anti-inflammatory drugs such as steroids, antibiotics, and indomethacin, and the possible anti-inflammatory role of other substances such as IL-1 receptor antagonists, erythropoietin, caffeine, estradiol, insulin-like growth factor, and melatonin as well as endogenous protectors, and genetic regulation of inflammation. If successful, these may decrease mortality and long-term morbidity among term and pre-term infants.