Autophagy precedes apoptosis during degeneration of the Kölliker’s organ in the development of rat cochlea

Gao

et al. 2021

Front. Cell Dev. Biol.

Self Cite

Greater epithelial ridge cells, a transient neonatal cell group in the cochlear duct, which plays a crucial role in the functional maturation of hair cell, structural development of tectorial membrane, and refinement of audio localization before hearing. Greater epithelial ridge cells are methodologically homogeneous, while whether different cell subtypes are existence in this intriguing region and the degeneration mechanism during postnatal cochlear development are poorly understood. In the present study, single-cell RNA sequencing was performed on the cochlear duct of postnatal rats at day 1 (P1) and day 7 (P7) to identify subsets of greater epithelial ridge cell and progression. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were used to examine genes enriched biological processes in these clusters. We identified a total of 26 clusters at P1 and P7 rats and found that the cell number of five cell clusters decreased significantly, while four clusters had similar gene expression patterns and biological properties. The genes of these four cell populations were mainly enriched in Ribosome and P13K-Akt signal pathway. Among them, Rps16, Rpsa, Col4a2, Col6a2, Ctsk, and Jun are particularly interesting as their expression might contribute to the greater epithelial ridge cells degeneration. In conclusion, our study provides an important reference resource of greater epithelial ridge cells landscape and mechanism insights for further understanding greater epithelial ridge cells degeneration during postnatal rat cochlear development.

Section: Discussionmentioning

confidence: 94%

Single-Cell RNA Sequencing Analysis Reveals Greater Epithelial Ridge Cells Degeneration During Postnatal Development of Cochlea in Rats

Gao

et al. 2021

Front. Cell Dev. Biol.

Self Cite

“…Most cells of the GER and the outer sulcus become post-mitotic 2-4 days after the organ of Corti in the mouse [19]. A large fraction of GER cells will disappear by postnatal day 14 through autophagy [35] and apoptosis [36].…”

Section: Figurementioning

confidence: 99%

Embryonic and Neonatal Mouse Cochleae Are Susceptible to Zika Virus Infection

Munnamalai

Sammudin

Young

et al. 2021

Viruses

Congenital Zika Syndrome (CZS) is caused by vertical transmission of Zika virus (ZIKV) to the gestating human fetus. A subset of CZS microcephalic infants present with reduced otoacoustic emissions; this test screens for hearing loss originating in the cochlea. This observation leads to the question of whether mammalian cochlear tissues are susceptible to infection by ZIKV during development. To address this question using a mouse model, the sensory cochlea was explanted at proliferative, newly post-mitotic or maturing stages. ZIKV was added for the first 24 h and organs cultured for up to 6 days to allow for cell differentiation. Results showed that ZIKV can robustly infect proliferating sensory progenitors, as well as post-mitotic hair cells and supporting cells. Virus neutralization using ZIKV-117 antibody blocked cochlear infection. AXL is a cell surface molecule known to enhance the attachment of flavivirus to host cells. While Axl mRNA is widely expressed in embryonic cochlear tissues susceptible to ZIKV infection, it is selectively downregulated in the post-mitotic sensory organ by E15.5, even though these cells remain infectible. These findings may offer insights into which target cells could potentially contribute to hearing loss resulting from fetal exposure to ZIKV in humans.

“…[42][43][44][45][46] Immunohistochemistry was essential to demonstrate the embryological origin of hemopoietic cells in non-mammalian vertebrates, 47,48 and to describe the interaction of non-myelinating Schwann cells with immune cells in the mouse lymphoid organs. [49][50][51] The basic cell mechanisms of apoptosis and autophagy proved to play key roles during the pre-and postnatal development of the cochlea in rodents 27,52,53 as well as during senescence in culture of sheep neurons and astrocytes. 54 The effect of cadmium was found to alter glial architecture in the lizard brain, 55 and to induce neurodegeneration in zebrafish embryos and adults, 56 while the effects of drug administration on the brain following trauma were studied in rat.…”

Section: A Possible Strategy To Widen the Audience Of A Histochemical Journalmentioning

confidence: 99%

A journal of histochemistry as a forum for non-histochemical scientific societies

2019

Histochemical techniques are widely applied in biomedical research and, during the last twenty years, they were among the methods used in more than 590,000 scientific articles in indexed journals. However, a very small percentage of these papers were published in strictly histochemical journals. A possible strategy to widen the audience of the histochemical journals making them attractive to non-histochemist authors might be to publish and make open-access available the proceedings of the meetings and conferences of valued scientific societies whose fellows use microscopy and histochemistry in their experimental activity. In the last years’ experience of the European Journal of Histochemistry, this approach was effective to increase the number of published articles on stem cells and development, connective tissue and nerve cell biology.