Effect of granulocyte colony-stimulating factor on the peripheral nerves in streptozotocin-induced diabetic rat

There are controversial reports about the effect of granulocyte colony-stimulating factor (G-CSF) in peripheral nerve protection. Therefore, the present study aimed to investigate the effect of G-CSF on peripheral nerves in streptozotocin (STZ) induced diabetic rats. After STZ or vehicle injection, rats were divided into five groups (n=6) as follows: normal+vehicle, normal+G-CSF (50 µg/kg for 5 days), diabetes mellitus (DM)+vehicle, DM+G-CSF (50 µg/kg for 5 days), and DM+G-CSF extension (50 µg/kg for 5 days and followed by two injections per week up to 24 weeks). Our results showed that the current perception threshold was not significantly different among experimental groups. G-CSF treatment inhibited the loss of cutaneous nerves and gastric mucosal small nerve fibers in morphometric comparison, but statistical significance was not observed. The present results demonstrated that G-CSF has no harmful but minimal beneficial effects with respect to peripheral nerve preservation in diabetic rats.