Fasudil, a Rho-Associated Protein Kinase Inhibitor, Attenuates Traumatic Retinal Nerve Injury in Rabbits.

Inhibition of RhoA/Rock could promote axon growth and alleviate optic nerve injury. However, the role of RhoA/Rock in the traumatic retinal nerve in vivo was not completely clear. In this study, we established a rabbit model of traumatic retinal nerve injury, and primary retinal ganglion cells (RGCs) were isolated and cultured under hypoxia-hypoglycemia condition that was mock to the microenvironment in the injured retinas in vivo. The Rock inhibitor fasudil was used to treat primary RGCs and ear vein injected into the model rabbits in vivo. RhoA/Rock signaling was activated in the injured optic nerve in rabbits. Western blotting analysis showed that RhoA/Rock signaling in the retina was activated during the traumatic optic neuropathy. Data on gene expression examination and Annexin V/PI dual staining combined with flow cytometry analysis displayed that fasudil injection reduced expression of Rho/Rock and apoptotic genes, as well as the apoptosis of RGCs in traumatic retinal nerve injury in vitro and in vivo. Moreover, fasudil injection reduced expression of Rho/Rock and apoptotic genes, as well as the apoptosis of RGCs in the rabbits with traumatic retinal nerve injury in vivo. In conclusion, fasudil treatment could significantly reduce the apoptosis of RGCs and relieved retinal nerve injury in vitro and in vivo.

Fasudil alleviates traumatic optic neuropathy by inhibiting Rho signaling pathway.

OBJECTIVES: The present study is to investigate the pathological changes in rabbits with traumatic optic neuropathy (TON), as well as the effect of fasudil on the lesions. METHODS: A total of 144 New Zealand rabbits were successfully established as TON models. Twelve hours after surgery, the rabbits in control, dexamethasone, and fasudil groups were administrated with saline, dexamethasone, and fasudil via ear veins, respectively. Then, retinas of the rabbits were obtained at 72 h and on days 7, 14 and 21 after surgery. The pathological changes in retina and optic nerves were observed by hematoxylin and eosin staining and transmission electron microscopy. The expression levels of Rho-associated genes were measured using quantitative real-time polymerase chain reaction. RESULTS: In control group, the axons were swelling, and mitochondria showed vacuolation after optic nerve crush. Mitochondria were swelled slightly in dexamethasone group. By contrast, nerves in fasudil group were repaired. Retinal ganglion cells in control group were reduced significantly due to optic nerve crush. The loss of retinal ganglion cells was alleviated in fasudil group. Quantitative real-time polymerase chain reaction showed that the expression of Rho-associated genes were down-regulated. CONCLUSIONS: The present study demonstrates that fasudil inhibits the apoptosis of retinal ganglion cells and ameliorates damages of optic nerves in traumatic optic neuropathy.