The possible therapeutic effect of mesenchymal stem cells on experimentally induced brain hypoxic-ischemic encephalopathy in neonatal rats

Background Hypoxic-ischemic encephalopathy (HIE) in neonates is a serious disorder, and till now, no curable treatment is available. Aim The present study was conducted to evaluate the therapeutic effect of bone marrow-derived mesenchymal stem cells (BM-MSCs) in attenuating the experimentally induced brain HIE in neonatal rats. Materials and methods Totally, 45 healthy neonatal rats (7 days old) were divided into three groups: group I was the control group. In group II (encephalopathy group), rats were exposed to surgical induction of hypoxic-ischemic (HI) brain injury and subdivided into two subgroups: group IIa rats were killed 3 days later to evaluate the histopathological changes and group IIb rats were killed after 28 days for recovery. In group III (encephalopathy+stem cell group), rats were exposed to surgical induction of HI brain injury and then underwent infusion with BMSCs through tail vein. Two behavior tests (the righting reflex and the geotaxis reflex) were performed 3, 7, 14, and 28 days after induction of HI brain injury. Cerebral cortex tissue was processed for histological and immunohistochemical (nestin, glial fibrillar acid protein, and neurofilaments) studies and for real-time PCR quantitative expression of vascular endothelial growth factor-receptor 2 and endothelial nitric oxide synthase genes. Results Group IIb (recovery) showed nearly the same picture as group IIa. Group III showed improvement in all parameters (neural function tests, histopathological studies, and genes expression) compared with group II. Conclusion BM-MSCs attenuated the HIE in rats, but compared with the normal control, this effect was still away.