Kye Hyang Lee

The neuroprotective effect of recombinant human erythropoietin via an antiapoptotic mechanism on hypoxic-ischemic brain injury in neonatal rats

PURPOSE The neuroprotective effects of erythropoietin (EPO) have been recently shown in many animal models of brain injury, including hypoxic-ischemic (HI) encephalopathy, trauma, and excitotoxicity; however, limited data are available for such effects during the neonatal periods. Therefore, we investigated whether recombinant human EPO (rHuEPO) can protect against perinatal HI brain injury via an antiapoptotic mechanism. METHODS The left carotid artery was ligated in 7-day-old Sprague-Dawley (SD) rat pups (in vivo model). The animals were divided into 6 groups: normoxia control (NC), normoxia sham-operated (NS), hypoxia only (H), hypoxia+vehicle (HV), hypoxia+rHuEPO before a hypoxic insult (HE-B), and hypoxia+rHuEPO after a hypoxic insult (HE-A). Embryonic cortical neuronal cell culture of SD rats at 18 days gestation (in vitro model) was performed. The cultured cells were divided into 5 groups: normoxia (N), hypoxia (H), and 1, 10, and 100 IU/mL rHuEPO-treated groups. RESULTS In the in vivo model, Bcl-2 expressions in the H and HV groups were lower than those in the NC and NS groups, whereas those in the HE-A and HE-B groups were greater than those of the H and HV groups. The expressions of Bax and caspase-3 and the ratio of Bax/Bcl-2 were in contrast to those of Bcl-2. In the in vitro model, the patterns of Bcl-2, Bax, and caspase-3 expression and Bax/Bcl-2 ratio were similar to the results obtained in the in vivo model. CONCLUSION rHuEPO exerts neuroprotective effect against perinatal HI brain injury via an antiapoptotic mechanism.

Transient asymptomatic white matter lesions following Epstein-Barr virus encephalitis

We present the case of a patient with Epstein-Barr virus (EBV) encephalitis who developed abnormal white matter lesions during the chronic phases of the infection. A 2-year-old-boy was admitted for a 2 day history of decreased activity with ataxic gait. The results of the physical examination were unremarkable except for generalized lethargy and enlarged tonsils with exudates. Brain magnetic resonance imaging (MRI) at admission showed multiple high signal intensities in both basal ganglia and thalami. The result of EBV polymerase chain reaction (PCR) of the cerebral spinal fluid was positive, and a serological test showed acute EBV infection. The patient was diagnosed with EBV encephalitis and recovered fully without any residual neurologic complications. Subsequently, follow-up MRI at 5 weeks revealed extensive periventricular white matter lesions. Since the patient remained clinically stable and asymptomatic during the follow-up period, no additional studies were performed and no additional treatments were provided. At the 1-year follow-up, cranial MRI showed complete disappearance of the abnormal high signal intensities previously seen in the white matter. The patient continued to remain healthy with no focal neurologic deficits on examination. This is the first case of asymptomatic self-limited white matter lesions seen in serial MRI studies in a Korean boy with EBV encephalitis.