Therapeutic restoration of miR-96 prevents hearing loss in mice through modulation of noise-induced and genetic pathways

Hearing loss often arises from impairments in multiple genes, complicating therapeutic development. MicroRNAs, as master regulators, offer promising targets for complex diseases. We explored <i>miR-96</i>'s roles in hair cell (HC) function and noise-induced hearing loss (NIHL), finding that <i>miR-96</i> ^-/-, not <i>miR-96</i> ^<i>+/-</i> , mice exhibited progressive hearing loss due to gene regulatory network dysregulation from <i>miR-96</i> loss in HCs not spiral ganglion neurons (SGNs). Viral-mediated delivery of <i>miR-96</i> into the inner ear partially rescued hearing of <i>miR-96</i> ^-/- mice. Tamoxifen-induced depletion of <i>miR-96</i> in adult <i>UBC</i> ^{<i>CreERT2/+</i>} ; <i>miR-96</i> ^<i>fl/fl</i> mice led to hearing loss, with <i>Bach2</i>, <i>Gabra2</i>, <i>Gabra4</i>, and <i>Grk1</i> upregulation and <i>Tnn</i>, <i>Col11a1</i>, <i>Gjb3</i>, and <i>Hnf4a</i> downregulation. Furthermore, noise trauma reduced <i>miR-96</i>, altering <i>Bach2</i>, <i>Bcl2l1</i>, <i>Slc26a9</i>, <i>Gabrb1</i>, <i>Grk1</i>, <i>Nos2</i>, and <i>Cyp1a1</i> expression, whereas <i>miR-96</i> overexpression protected hearing against noise by reversing the expression of <i>Bach2</i>, <i>Bcl2l1</i>, and <i>Cyp1a1</i>. Our findings underscore <i>miR-96</i>'s essential role in adult hearing maintenance and NIHL prevention, presenting it as a promising therapeutic target.