Hippocampal Stem Cell Grafting-Mediated Recovery of Injured Hippocampus in the Rat Model of Temporal Lobe Epilepsy

Abstract

Hippocampal stem cells (HSCs) are considered promising donor cells to promote reorganization of degenerated regions of the injured hippocampus in the epileptic brain. However, the efficacy of HSC grafting for repairing injured hippocampus remains unclear. To address this issue, we transplanted neonatal rat HSCs into the right hippocampus in rats with kainite acid (KA)-induced epilepsy. The activity of the hippocampus and amygdala nucleus was monitored with electroencephalogram (EEG) throughout 24 weeks posttransplantation. Rats with grafted HSCs exhibited reduced frequency of epileptic wave discharge and a 50% decrease in the amplitude of discharge. At 1, 4, 8, and 24 weeks posttransplantation, the aberrant mossy fiber sprouting (MFS) was evaluated with Timm's stain and the number of CA3 pyramidal neurons was analyzed with Nissl staining. Aberrant MFS induced by KA-lesion was notably suppressed by HSC grafts beginning 4 weeks posttransplantation, and was most effective by 8 weeks. In addition, the loss of CA3 pyramidal neurons was partially restored and reached the most recovery at 8 weeks. Taken together, these results suggest that HSCs derived from the postnatal hippocampus offer a promising reparative effect on KA-induced epileptic brain.

Bone marrow mononuclear cells reduce seizure frequency and improve cognitive outcome in chronic epileptic rats

“…Ruschenschmidt et al (2005) have demonstrated that embryonic stem cell-derived neurons display characteristic properties of neurons when transplanted in the hippocampi of chronic epileptic animals. The same grafting technique using striatal precursors, adult neural stem cells or hippocampal stem cells in an acute period of the disease reduced seizure frequency in chronic epilepsy (Hattiangady et al, 2008;Jing et al, 2009;Shen et al, 2010). Choosing a different method of administration, Chu et al (2004) evaluated the effects of intravenously injected neural stem/ progenitor cells on SRS.…”

“…Life Sciences j o u r n a l h o m e p a g e : w w w. e l s ev i e r. c o m / l o c a t e / l i f e s c i e Jing et al, 2009;Li et al, 2009b;Ruschenschmidt et al, 2005;Shen et al, 2010;Zaman et al, 2000). Recently, Costa-Ferro et al (2010) showed that bone marrow mononuclear cells (BMMCs) can prevent the development of chronic seizures, reduce neuronal loss, and influence the reorganization of the hippocampal network in the acute phase of experimental epilepsy.…”

Current Status and Potential Challenges of Cell-Based Therapy for Treating Status Epilepticus and Chronic Epilepsy

“…Hong Shen et al [62] demonstrated that Hippocampal stem cells (HSCs) derived from the postnatal hippocampus have the potential of promoting repairs in the epileptic brain. In this study, Hippocampal stem cells were transplanted into the right hippocampus in rats with kainite acid [KA]-induced epilepsy.…”