Related Experiment Video
Updated: May 8, 2026
Investigations on Alterations of Hippocampal Circuit Function Following Mild Traumatic Brain Injury
Published on: November 19, 2012
Erythropoietin improved cognitive function and decreased hippocampal caspase activity in rat pups after traumatic
Michelle E Schober1, Daniela F Requena, Benjamin Block
11 Department of Pediatrics, Division of Critical Care, University of Utah , Salt Lake City, Utah.
Insights
Erythropoietin (EPO) improved memory and increased neuron survival in young rats after traumatic brain injury (TBI). This study explored EPO
Area of Science:
- Neuroscience
- Developmental Biology
- Pharmacology
Background:
- Traumatic brain injury (TBI) is a major cause of acquired neurological disability in children.
- Erythropoietin (EPO), an anti-apoptotic cytokine, has shown promise in improving cognitive outcomes in adult TBI models.
- However, the effects of EPO in developmental TBI models remain uninvestigated.
Purpose of the Study:
- To investigate the efficacy of Erythropoietin (EPO) in improving cognitive outcomes in young rats subjected to controlled cortical impact (CCI).
- To determine if EPO administration increases the neuron fraction in the hippocampus of developing rats post-TBI.
Main Methods:
- Controlled cortical impact (CCI) was induced in 17-day-old rat pups.
- Erythropoietin (EPO) or vehicle was administered at specific time points post-injury.
- Cognitive function was assessed using Novel Object Recognition (NOR) test.
- Hippocampal EPO levels, apoptosis markers (caspase activity, mRNA of Bcl2, Bax, Bcl-xL, Bad), and neuron fraction were analyzed.
Main Results:
- EPO administration normalized recognition memory in rat pups following CCI.
- EPO treatment blunted the increase in hippocampal caspase activity induced by CCI.
- A significant increase in the neuron fraction within the CA3 region of the hippocampus was observed after EPO treatment.
- Exogenous EPO levels in the brain were relatively low compared to endogenous levels.
Conclusions:
- Erythropoietin (EPO) demonstrates therapeutic potential in improving cognitive function after developmental TBI in rats.
- EPO enhances neuronal survival by inhibiting caspase-dependent apoptosis in the early stages following injury.
- These findings suggest EPO as a potential neuroprotective agent for pediatric TBI.
Unlabelled:
Traumatic brain injury (TBI) is a leading cause of acquired neurologic disability in children. Erythropoietin (EPO), an anti-apoptotic cytokine, improved cognitive outcome in adult rats after TBI. To our knowledge, EPO has not been studied in a developmental TBI model.
Hypothesis:
We hypothesized that EPO would improve cognitive outcome and increase neuron fraction in the hippocampus in 17-day-old (P17) rat pups after controlled cortical impact (CCI).
Methods:
EPO or vehicle was given at 1, 24, and 48 h after CCI and at post injury day (PID) 7. Cognitive outcome at PID14 was assessed using Novel Object Recognition (NOR). Hippocampal EPO levels, caspase activity, and mRNA levels of the apoptosis factors Bcl2, Bax, Bcl-xL, and Bad were measured during the first 14 days after injury. Neuron fraction and caspase activation in CA1, CA3, and DG were studied at PID2.
Results:
EPO normalized recognition memory after CCI. EPO blunted the increased hippocampal caspase activity induced by CCI at PID1, but not at PID2. EPO increased neuron fraction in CA3 at PID2. Brain levels of exogenous EPO appeared low relative to endogenous. Timing of EPO administration was associated with temporal changes in hippocampal mRNA levels of EPO and pro-apoptotic factors. Conclusion/Speculation: EPO improved recognition memory, increased regional hippocampal neuron fraction, and decreased caspase activity in P17 rats after CCI. We speculate that EPO improved cognitive outcome in rat pups after CCI as a result of improved neuronal survival via inhibition of caspase-dependent apoptosis early after injury.
