Molecular Basis of Hair Cell Loss

The document from 2015 reviews the molecular mechanisms of hair cell loss, a major cause of hearing impairment, highlighting that outer hair cells and high-frequency cells are particularly vulnerable. It identifies reactive oxygen species (ROS) as a common factor in hair cell death, leading to intrinsic apoptosis via the mitochondrial pathway, and also discusses extrinsic apoptosis, necrosis, and necroptosis as other cell death routes. The review notes that mammals, including humans, cannot regenerate hair cells, making the loss permanent. It also explores the role of micro-RNAs in regulating apoptosis, the damaging effects of ototoxic drugs like aminoglycoside antibiotics and cisplatin, and the involvement of macrophages in clearing debris from necrosis. Despite identifying potential therapeutic agents such as antioxidants and inhibitors of cell-death pathways, the document concludes that effective clinical treatments for cochlear damage have not yet been established, though research continues in hopes of finding a solution to prevent or mitigate hearing loss.