Mitochondrial dysfunction in hearing loss

Mitochondrial pathology plays an important role in both inherited and acquired hearing loss. Inherited mitochondrial DNA mutations have been implicated in both syndromic and non-syndromic hearing loss, as well as in predisposition to aminoglycoside ototoxicity. Acquired mitochondrial dysfunction in the absence of mitochondrial DNA mutations has also been proposed as playing an important role in noise-induced and toxin-induced hearing loss. Presbycusis, the hearing loss associated with aging, may be caused by mitochondrial dysfunction resulting from the accumulation of acquired mitochondrial DNA mutations and other factors. The pathophysiological mechanisms and clinical implications of these findings are discussed. (C) 2004 Published by Elsevier B.V. on behalf of Mitochondria Research Society.