Lithium Alters the Morphology of Neurites Regenerating from Cultured Adult Spiral Ganglion Neurons.

Lithium Alters the Morphology of Neurites Regenerating from Cultured Adult Spiral Ganglion Neurons. Hear Res. 2013 Jul 12; Authors: Shah SM, Patel CH, Feng AS, Kollmar R Abstract The small-molecule drug lithium (as a monovalent ion) promotes neurite regeneration and functional recovery, is easy to administer, and is approved for human use to treat bipolar disorder. Lithium exerts its neuritogenic effect mainly by inhibiting glycogen synthase kinase 3, a constitutively-active serine/threonine kinase that is regulated by neurotrophin and "wingless-related MMTV integration site" (Wnt) signaling. In spiral ganglion neurons of the cochlea, the effects of lithium and the function of glycogen synthase kinase 3 have not been investigated. We, therefore, set out to test whether lithium modulates neuritogenesis from adult spiral ganglion neurons. Primary cultures of dissociated spiral ganglion neurons from adult mice were exposed to lithium at concentrations between 0 and 12.5 mM. The resulting neurite morphology and growth-cone appearance were measured in detail by using immunofluorescence microscopy and image analysis. We found that lithium altered the morphology of regenerating neurites and their growth cones in a differential, concentration-dependent fashion. Low concentrations of 0.5 to 2.5 mM (around the half-maximal inhibitory concentration for glycogen synthase kinase 3 and the recommended therapeutic serum concentration for bipolar disorder) en...
Source: Hearing Research - Category: Audiology Authors: Tags: Hear Res Source Type: research