Clin Exp Otorhinolaryngol.  2024 Feb;17(1):1-14. 10.21053/ceo.2023.01382.

Hair Cell Regeneration: From Animals to Humans

• Choi SW
• Abitbol JM
• Cheng AG

• KMID: 2553051
• DOI: http://doi.org/10.21053/ceo.2023.01382

Abstract

Cochlear hair cells convert sound into electrical signals that are relayed via the spiral ganglion neurons to the central auditory pathway. Hair cells are vulnerable to damage caused by excessive noise, aging, and ototoxic agents. Non-mammals can regenerate lost hair cells by mitotic regeneration and direct transdifferentiation of surrounding supporting cells. However, in mature mammals, damaged hair cells are not replaced, resulting in permanent hearing loss. Recent studies have uncovered mechanisms by which sensory organs in non-mammals and the neonatal mammalian cochlea regenerate hair cells, and outlined possible mechanisms why this ability declines rapidly with age in mammals. Here, we review similarities and differences between avian, zebrafish, and mammalian hair cell regeneration. Moreover, we discuss advances and limitations of hair cell regeneration in the mature cochlea and their potential applications to human hearing loss.

Keyword

Hearing Loss; Cochlea; Hair Cells, Regeneration

Figure

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  Fig. 1. Hair cell regeneration in the chicken basilar papilla. (A) Microscopic image of a whole-mount preparation of the basilar papilla. Image courtesy of Nesrine Benkafadar. (B) Schematic image of the cross-sectional anatomy of the basilar papilla. (C) Mechanisms of hair cell regeneration in chicken basilar papilla. VEGF, vascular endothelial growth factor; FGF, fibroblast growth factor; JAK/STAT, Janus kinase/signal transducer and activator of transcription.

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  Fig. 2. Hair cell regeneration in the zebrafish lateral line neuromast. (A) Schematic image of the zebrafish lateral line neuromast. (B) Mechanisms of hair cell regeneration in the zebrafish lateral line neuromast. Fgf, fibroblast growth factor.

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  Fig. 3. Schematic image of the mature organ of Corti. IBC, inner border cell; IPhC, inner phalangeal cell; IPC, inner pillar cell; OPC, outer pillar cell; DC, Deiters’ cell.

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  Fig. 4. Hair cell regeneration in neonatal mammals’ organ of Corti. (A) Schematic image of the neonatal mammalian organ of Corti. (B) Mechanisms of hair cell regeneration in the neonatal mammalian organ of Corti. GER, greater epithelial ridge; IBC, inner border cell; IPhC, inner phalangeal cell; PC, pillar cell; DC, Deiters’ cell; HeC, Hensen cell; LER, lesser epithelial ridge.

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