Erythropoietin (Epo) prevents ischemia and hypoxia-induced neuronal death in vitro. Recent studies have shown that this cytokine also has in vivo neuroprotective effects in cerebral and spinal ischemia in adult rodents. In this study, we aimed to investigate the effect of systemically administered recombinant human Epo on infarct volume and apoptotic neuronal death in a newborn rat hypoxic-ischemic brain injury model. Our results showed that a single dose of intraperitoneal Epo treatment (1,000 U/kg) significantly decreased the mean infarct volume as compared to the control group. In contrast to the Epo-treated group, histopathological examination by positive terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling of the affected brain in control animals revealed widespread neuronal injury associated with numerous apoptotic cells. Morphometric analysis to determine the extent of damage quantitatively ascertained that the mean infarct volume was significantly lower in the Epo-treated group (p < 0.003). These results suggest the beneficial neuroprotective effect of Epo in this model of neonatal hypoxic-ischemic brain injury. To our knowledge, this is the first study that demonstrates a protective effect of Epo against hypoxia-ischemia in the developing brain.

Background: We have previously shown that erythropoietin (Epo) exerts neuroprotective effects in the Rice-Vannucci model of neonatal hypoxic-ischemic brain injury. However, the mechanisms of Epo protection in this model are still unclear. Objectives: In the present study, we studied the effects of systemically administered Epo on lipid peroxidation levels and antioxidant enzyme (superoxide dismutase and glutathione peroxidase) activities following hypoxic-ischemic brain injury in neonatal rats. Methods: Seven-day-old Wistar rat pups were subjected to left carotid artery occlusion followed by 2.5 h of hypoxic exposure. Brain lipid peroxidation levels and antioxidant enzyme activities were measured in the injured hemispheres 24 h after the hypoxic-ischemic insult. Results: Hypoxic-ischemic injury significantly increased the thiobarbituric acid-reactive substance levels in the injured hemispheres as compared to the control group. In addition, glutathione peroxidase activity was significantly elevated in Epo-treated animals compared to saline-treated animals and the control group. Conclusions: These results suggest that Epo exerts neuroprotective effects against hypoxic-ischemic brain injury at least partially via the modulation of antioxidant enzyme activity.

Progressive compromise of antioxidant defenses and free radical-mediated lipid peroxidation, which is one of the major mechanisms of secondary traumatic brain injury (TBI), has also been reported in pediatric head trauma. In the present study, we aimed to demonstrate the effect of melatonin, which is a potent free radical scavenger, on brain oxidative damage in 7-day-old rat pups subjected to contusion injury. Whereas TBI significantly increased thiobarbituric acid reactive substances (TBARS) levels, there was no compensatory increase in the antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GPx) 24 hours after TBI in 7-day-old rats. Melatonin administered as a single dose of 5 mg/kg prevented the increase in TBARS levels in both non-traumatized and traumatized brain hemispheres. In conclusion, melatonin protects against oxidative damage induced by TBI in the immature brain.

Aim: This study aimed to compare the recently published prescriptive INTERGROWTH-21st standards with commonly used intrauterine based Fenton growth standards in terms of birth size classification and extrauterine growth restriction (EUGR) incidence in a sample of very preterm infants. Methods: The anthropometric measures of preterm infants born before 32 weeks of gestation at the Dokuz Eylul University Hospital during the period from January 2012 to February 2016 were obtained at birth, at the 36th gestational weeks or at the time of discharge. Birth and growth data were presented as percentiles according to the two reference standards. Results: A total of 248 infants with mean gestational age of 29.1 ± 2.1 weeks were included. The small for gestational age (SGA) rate was significantly higher (12 versus 15%, p = .004) and the EUGR rate was significantly lower (40.2 versus 31.5%, p < .001) with the INTERGROWTH-21st charts compared with the Fentons’. Twenty-four per cent of the infants who were accepted as SGA according to the INTERGROWTH-21st standards were appropriate for gestational age (AGA) according to the Fenton preterm growth charts. However, these newly identified SGA infants according to the Intergrowth-21st standards did not have increased risks of early morbidities. Furthermore, 77% of the cases who had EUGR due to the Fenton standards were categorized as EUGR when evaluated using the INTERGROWTH-21st standards. Conclusions: Results indicated that almost one out of every five cases assessed as EUGR according to Fenton standards was within the normal interval according to Intergrowth standards. On the contrary, one out of every four cases assessed as SGA according to the INTERGROWTH-21st standards was within the normal interval according to Fentons’. These differences observed with INTERGROWTH-21st standards may affect in-hospital and postdischarge nutrition plan of these vulnerable infants. However, new standards are needed to be evaluated against currently used ones before they are implemented and further studies should be conducted to evaluate the functional impact of these differences on long-term outcomes including neurologic and cardio-metabolic morbidities.

Periventricular leukomalacia (PVL), a common neonatal brain white matter (WM) lesion, is frequently associated with cerebral palsy. Growing evidence has indicated that in addition to ischemia/reperfusion injury, cytokine-induced brain injury associated with maternal or fetal infection may also play an important role in the pathogenesis of PVL. Recent studies have shown that administration of lipopolysaccharide (LPS) to pregnant rats causes enhanced expression of the cytokines, i.e., IL-1β, TNF-α, and IL-6, in fetal brains. In recent years, it has been shown that erythropoietin (EPO) has a critical role in the development, maintenance, protection and repair of the nervous system. In the present study we investigated the effect of EPO on LPS-induced WM injury in Sprague-Dawley rats. LPS (500 µg/kg) suspension in pyrogen-free saline was administered intraperitoneally to pregnant rats at 18 and 19 days of gestation. The control group was treated with pyrogen-free saline. They were given 5,000 U/kg recombinant human EPO. Seven-day-old Sprague-Dawley rat pups were divided into four groups: control group, LPS-treated group, prenatal maternal EPO-treated group (5,000 U/kg, intraperitoneally given to pregnant rats at 18 and 19 days of gestation), and postnatal EPO-treated group (5,000 U/kg, intraperitoneally given to 1-day-old rat pups). Cytokine induction in the postnatal 7-day-old (P7) rat brain after maternal administration of LPS was determined by the ELISA method. The proinflammatory cytokine levels (IL-1β, TNF-α, and IL-6) in P7 rat pup brains were significantly increased in the LPS-treated group as compared with the control group. Prenatal maternal EPO treatment significantly reduced the concentration of TNF-α and IL-6 in the newborn rat brain following LPS injection. The concentration of IL-1β was decreased in the intrauterine EPO treatment group. Postnatal EPO treatment significantly decreased only the IL-6 concentration in the newborn rat brain following LPS injection. The concentration of cytokines, IL-1β and TNF-α, was reduced in the postnatal EPO treatment group. We demonstrated here that LPS administration in pregnant rats at gestational day 18 and 19 induced WM injury in P7 progeny characterized by apoptosis. Prenatal maternal and postnatal EPO treatment significantly reduced the number of apoptotic cells in the periventricular WM. Using immunohistochemistry techniques, we investigated the effects of maternal administration of LPS on myelin basic protein (MBP) staining, as a marker of myelination in the periventricular area in the neonatal rat brain. MBP staining was significantly less and weaker in the brains of the LPS-treated group as compared with the prenatal maternal EPO-treated group. However, the postnatal EPO treatment did not prevent LPS-stimulated loss of MBP-positive staining. In conclusion, especially prenatal maternal EPO treatment attenuates LPS-induced injury by reducing the expression of inflammatory cytokines and sparing MBP in the neonatal rat brain. While the postnatal EPO treatment prevented LPS-induced brain injury this effect was partial. To our knowledge, this is the first study that demonstrates a protective effect of EPO on LPS-induced WM injury in the developing brain. Regarding the wide use of EPO in premature newborns, this agent may be potentially beneficial in treating LPS-induced brain injury in the perinatal period.