Preventive effect of erythropoietin on spinal cord cell apoptosis following acute traumatic injury in rats.
METHODS
Using a rat spinal cord injury (SCI) model, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL), anti-active caspase-3 antibody staining, histological examination, and histochemical studies were used to examine the antiapoptotic effect of erythropoietin.


OBJECTIVE
To evaluate in detail the antiapoptotic effect of erythropoietin following SCI.


BACKGROUND
Although some investigators have reported antiapoptotic effects of erythropoietin using the TUNEL method, it has not been determined whether erythropoietin can prevent both acute neuronal death and secondary injury. Therefore, we examined the temporal and spatial effects of erythropoietin using TUNEL and active caspase-3 following SCI.


METHODS
An in vitro study used a cerebrocortical culture in which the antiapoptotic effect of erythropoietin was examined after N-methyl-D-aspartate treatment. Using an in vivo study, rats with SCI received erythropoietin intraperitoneally, and were examined histologically and immunohistochemically with TUNEL, active caspase-3, and cell markers between 6 hours and 7 days after injury.


RESULTS
Cerebrocortical culture confirmed an antiapoptotic effect of erythropoietin. Erythropoietin treatment significantly decreased TUNEL-positive apoptotic neurons and oligodendrocytes as early as 6 hours after SCI in rats. This antiapoptotic effect was observed until 7 days after injury. In addition, erythropoietin treatment significantly decreased the number of active caspase-3 immunoreactive cells within the SCI. In the in vitro study, cerebrocortical culture confirmed an antiapoptotic effect of erythropoietin.


CONCLUSIONS
These findings suggest that exogenous erythropoietin decreases the number of apoptotic cells observed between the very early and subchronic stages following traumatic SCI.
Arishima
Yoshiya
Y
Department of Orthopaedic Surgery, Kagoshima Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
Setoguchi
Takao
T
Yamaura
Ichiro
I
Yone
Kazunori
K
Komiya
Setsuro
S
D000818:Animals; D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology; D002478:Cells, Cultured; D004921:Erythropoietin / Q000494:pharmacology* / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D018696:Neuroprotective Agents / Q000494:pharmacology / Q000627:therapeutic use; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins; D013116:Spinal Cord / Q000187:drug effects / Q000473:pathology* / Q000502:physiology; D013119:Spinal Cord Injuries / Q000188:drug therapy / Q000473:pathology / Q000517:prevention & control*
D018696:Neuroprotective Agents; D011994:Recombinant Proteins; D004921:Erythropoietin