CDNF is a member of the ARMET family and acts as a trophic factor for neurons. CDNF inhibits the (6-OHDA)-induced degeneration of neurons. When CDNF controlled after 6-OHDA-lesioning, it reestablishes the function and inhibits the degeneration of neurons in substantia nigra. CDNF is universally expressed in neuronal and non-neuronal tissues. The highest levels in the brain are found in the optic nerve and corpus callosum.