Rho/ROCK pathway and neural regeneration: a potential therapeutic target for central nervous system and optic nerve damage.

Rho-associated kinase (ROCK) is a serine/threonine kinase and one of the major downstream effectors of the small GTPase RhoA. The Rho/ROCK pathway is closely related to the pathogenesis of several central nervous system (CNS) disorders, and involved in many aspects of neuronal functions including neurite outgrowth and retraction. In the adult CNS, the damaged neuron regeneration is very difficult due to the presence of myelin-associated axon growth inhibitors such as Nogo, myelin-associated glycoprotein (MAG) and oligodendrocyte-myelin glycoprotein (Omgp), etc. The effects of these axon growth inhibitors are reversed by blocking the Rho/ROCK pathway in vitro, and the inhibition of Rho/ROCK pathway can promote axon regeneration and functional recovery in the injured CNS in vivo. In addition, the therapeutic effects of the Rho/ROCK inhibitors have also been demonstrated in some animal models and the Rho/ROCK pathway becomes an attractive target for the development of drugs for treating CNS disorders. In this review, we summarized on the effect of the Rho and the downstream factor ROCK in neural regeneration, and the potential therapeutic effect of Rho/ROCK inhibitors in the survival and axonal regeneration of retinal ganglion cells was also discussed.