Abstract
Neuroimmunophilin ligands are a class of compounds that hold great promise for the treatment of nerve injuries and neurological disease. In contrast to neurotrophins (e.g., nerve growth factor), these compounds readily cross the blood-brain barrier, being orally effective in a variety of animal models of ischaemia, traumatic nerve injury and human neurodegenerative disorders. A further distinction is that neuroimmunophilin ligands act via unique receptors that are unrelated to the classical neurotrophic receptors (e.g., trk), making it unlikely that clinical trials will encounter the same difficulties found with the neurotrophins. Another advantage is that two neuroimmunophilin ligands (cyclosporin A and FK-506) have already been used in humans (as immunosuppressant drugs). Whereas both cyclosporin A and FK-506 demonstrate neuroprotective actions, only FK-506 and its derivatives have been clearly shown to exhibit significant neuroregenerative activity. Accordingly, the neuroprotective and neuroregenerativ...