Role of Wnt and Notch signaling in regulating hair cell regeneration in the cochlea

Abstract

Sensory hair cells in the inner ear are responsible for sound recognition. Damage to hair cells in adult mammals causes permanent hearing impairment because these cells cannot regenerate. By contrast, newborn mammals possess limited regenerative capacity because of the active participation of various signaling pathways, including Wnt and Notch signaling. The Wnt and Notch pathways are highly sophisticated and conserved signaling pathways that control multiple cellular events necessary for the formation of sensory hair cells. Both signaling pathways allow resident supporting cells to regenerate hair cells in the neonatal cochlea. In this regard, Wnt and Notch signaling has gained increased research attention in hair cell regeneration. This review presents the current understanding of the Wnt and Notch signaling pathways in the auditory portion of the inner ear and discusses the possibilities of controlling these pathways with the hair cell fate determiner Atoh1 to regulate hair cell regeneration in the mammalian cochlea.

Keywords

inner ear / cochlea / hair cell / regeneration / Wnt / Notch / signaling pathways

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Acknowledgements

This work was supported by grants from the National Basic Research Program of China (973 Program, No. 2015CB965000), the National Natural Science Foundation of China (Nos. 81570911, 81470692, 81470687, 81371094, 81230019, 81500790, 81570921, 31500852, and 31501194), the Jiangsu Province Natural Science Foundation (Nos. BK20150022, BK20140620, and BK20150598), and the Fundamental Research Funds for the Central Universities (Nos. 2242014R30022, and 021414380037).

Compliance with ethics guidelines

Muhammad Waqas, Shasha Zhang, Zuhong He, Mingliang Tang, and Renjie Chai declare that they have no conflicts of interest. This manuscript is a review article and does not involve a research protocol requiring approval by the relevant institutional review board or ethics committee.

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2016 Higher Education Press and Springer-Verlag Berlin Heidelberg