Effects of hydroxyethyl-starch-bound deferoxamine on ischemia/reperfusion injury in chronic nerve compression

The authors have demonstrated previously that pretreatment with deferoxamine, an iron chelator and antioxidant, at the time of release in acute nerve compression, provided protection against ischemia/reperfusion (I/R) injury. In the present study, they evaluated whether therapeutic intervention with hydroxyethyl-starch-bound deferoxamine (HES-DFO) at the time of release of the chronically-compressed peripheral nerve protects the nerve from I/R injury. The sciatic nerves of 43 male Sprague-Dawley rats, weighing 325 to 350 g, were subjected to 8 weeks of compression with Silastic tubing. The treatment group received intravenous HES-DFO (70 mg/kg) at the time of decompression, while the control group received an equal volume of intravenous hetastarch vehicle at the same time schedule and route. Nerve-tissue samples from the compression site, as well as contralateral noncompressed nerves, were assayed for malondialdehyde (MDA), a marker of I/R injury. The control group exhibited MDA levels up to five times normal, and did not return to normal for 21 days. In contrast, the HES-DFO group had MDA levels that were not statistically significantly different from normal levels. The results confirm that pretreatment with HES-DFO prior to the surgical decompression of chronically-compressed nerve provides marked protection against I/R injury.