Parity Attenuates Intraepithelial Corneal Sensory Nerve Loss in Female Mice
Aging impacts the ocular surface and reduces intraepithelial corneal nerve (ICN) density in male and female mice. Many researchers use retired breeders to study naturally aged female mice. Yet, the impact of parity and the length of time since breeders were retired on age-related changes in the intr...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-07-01
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| Series: | International Journal of Molecular Sciences |
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| Online Access: | https://www.mdpi.com/1422-0067/21/14/5172 |
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| author | Mary Ann Stepp Sonali Pal-Ghosh Gauri Tadvalkar Cintia S. de Paiva |
| author_facet | Mary Ann Stepp Sonali Pal-Ghosh Gauri Tadvalkar Cintia S. de Paiva |
| author_sort | Mary Ann Stepp |
| collection | DOAJ |
| description | Aging impacts the ocular surface and reduces intraepithelial corneal nerve (ICN) density in male and female mice. Many researchers use retired breeders to study naturally aged female mice. Yet, the impact of parity and the length of time since breeders were retired on age-related changes in the intraepithelial corneal nerves is not known. Here we study 2 month (M) nulliparous (NP) females as well as 9M, 10M, and 11M NP and multiparous (MP) female mice to determine whether parity impacts the age-related decline seen in corneal axon density; 9M male mice are also included in these assessments. After showing that parity attenuates age-related loss in axon density, we also assess the impact of parity on corneal epithelial cell proliferation and find that it impacts cell proliferation and axon density normalized by cell proliferation. Stromal nerve arborization is also impacted by aging with parity enhancing stromal nerves in older mice. qPCR was performed on 20 genes implicated in ICN density using corneal epithelial RNA isolated from 10M NP and MP mice and showed that NGF expression was significantly elevated in MP corneal epithelium. Corneal sensitivity was significantly higher in 9M MP mice compared to NP mice and increased sensitivity in MP mice was accompanied by increased nerve terminals in the apical and middle cell layers. Together, these data show that parity in mice attenuates several aspects of the age-related decline seen on the ocular surface by retaining sensory axons and corneal sensitivity as mice age. |
| first_indexed | 2024-03-10T18:19:08Z |
| format | Article |
| id | doaj.art-ad5a054e8a5243ed8cfaa0951ec0ea41 |
| institution | Directory Open Access Journal |
| issn | 1661-6596 1422-0067 |
| language | English |
| last_indexed | 2024-03-10T18:19:08Z |
| publishDate | 2020-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | International Journal of Molecular Sciences |
| spelling | doaj.art-ad5a054e8a5243ed8cfaa0951ec0ea412023-11-20T07:29:27ZengMDPI AGInternational Journal of Molecular Sciences1661-65961422-00672020-07-012114517210.3390/ijms21145172Parity Attenuates Intraepithelial Corneal Sensory Nerve Loss in Female MiceMary Ann Stepp0Sonali Pal-Ghosh1Gauri Tadvalkar2Cintia S. de Paiva3Department of Anatomy and Regenerative Biology, The George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USADepartment of Anatomy and Regenerative Biology, The George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USADepartment of Anatomy and Regenerative Biology, The George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USAOcular Surface Center, Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, TX 77030, USAAging impacts the ocular surface and reduces intraepithelial corneal nerve (ICN) density in male and female mice. Many researchers use retired breeders to study naturally aged female mice. Yet, the impact of parity and the length of time since breeders were retired on age-related changes in the intraepithelial corneal nerves is not known. Here we study 2 month (M) nulliparous (NP) females as well as 9M, 10M, and 11M NP and multiparous (MP) female mice to determine whether parity impacts the age-related decline seen in corneal axon density; 9M male mice are also included in these assessments. After showing that parity attenuates age-related loss in axon density, we also assess the impact of parity on corneal epithelial cell proliferation and find that it impacts cell proliferation and axon density normalized by cell proliferation. Stromal nerve arborization is also impacted by aging with parity enhancing stromal nerves in older mice. qPCR was performed on 20 genes implicated in ICN density using corneal epithelial RNA isolated from 10M NP and MP mice and showed that NGF expression was significantly elevated in MP corneal epithelium. Corneal sensitivity was significantly higher in 9M MP mice compared to NP mice and increased sensitivity in MP mice was accompanied by increased nerve terminals in the apical and middle cell layers. Together, these data show that parity in mice attenuates several aspects of the age-related decline seen on the ocular surface by retaining sensory axons and corneal sensitivity as mice age.https://www.mdpi.com/1422-0067/21/14/5172corneal sensory nervesagingpregnancymouseparitycorneal sensitivity |
| spellingShingle | Mary Ann Stepp Sonali Pal-Ghosh Gauri Tadvalkar Cintia S. de Paiva Parity Attenuates Intraepithelial Corneal Sensory Nerve Loss in Female Mice International Journal of Molecular Sciences corneal sensory nerves aging pregnancy mouse parity corneal sensitivity |
| title | Parity Attenuates Intraepithelial Corneal Sensory Nerve Loss in Female Mice |
| title_full | Parity Attenuates Intraepithelial Corneal Sensory Nerve Loss in Female Mice |
| title_fullStr | Parity Attenuates Intraepithelial Corneal Sensory Nerve Loss in Female Mice |
| title_full_unstemmed | Parity Attenuates Intraepithelial Corneal Sensory Nerve Loss in Female Mice |
| title_short | Parity Attenuates Intraepithelial Corneal Sensory Nerve Loss in Female Mice |
| title_sort | parity attenuates intraepithelial corneal sensory nerve loss in female mice |
| topic | corneal sensory nerves aging pregnancy mouse parity corneal sensitivity |
| url | https://www.mdpi.com/1422-0067/21/14/5172 |
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