This treatment is currently in active clinical trials. A γ-secretase inhibitor of Notch signaling was shown to induce new hair cells and partially recover hearing loss. Auditory hair cell loss is permanent damage due to the inability of these cells to regenerate. Therefore, deafness due to this pathology is viewed as irreversible. Hair cell development is mediated by Notch signaling, which exerts lateral inhibition onto hair cells. Notch signaling in supporting hair cells leads to prevention of differentiation in surrounding hair cells. After identifying a potent γ-secretase inhibitor selective for stimulating differentiation in inner ear stem cells, it was administered in acoustically injured mice. The animals who received the injury and treatment displayed an increased hair cell number and stimulated hearing recovery. This suggests that γ-secretase inhibition of Notch signaling can be a potential pharmacological therapy in approaching what was previously viewed as permeant deafness. Stem cell therapy
A fetal thymus graft, or rejuvenation of the recipient immunity by inoculation of young CD4+ T cells, also prevents presbycusis as well as up-regulation of the interleukin 1 receptor type II gene (IL1R2) in CD4+ T cells and degeneration of the spiral ganglion in Samp1 mice, a murine model of human senescence. This technology remains years or even decades away from human application.
U.S. National Library of Medicine.