Age-Related RPE Changes in Wildtype C57BL/6J Mice Between 2 and 32 Months

Overview

Journal bioRxiv

Date 2024 Feb 14

PMID 38352604

Authors

Debresha A Shelton

Isabelle Gefke

Vivian Summers

Yong-Kyu Kim

Hanyi Yu

Yana Getz

Salma Ferdous

Kevin Donaldson

Kristie Liao

Jack T Papania

Micah A Chrenek

Jeffrey H Boatright

John M Nickerson

Affiliations

Soon will be listed here.

Abstract

Purpose: This study provides a systematic evaluation of age-related changes in RPE cell structure and function using a morphometric approach. We aim to better capture nuanced predictive changes in cell heterogeneity that reflect loss of RPE integrity during normal aging. Using C57BL6/J mice ranging from P60-P730, we sought to evaluate how regional changes in RPE shape reflect incremental losses in RPE cell function with advancing age. We hypothesize that tracking global morphological changes in RPE is predictive of functional defects over time.

Methods: We tested three groups of C57BL/6J mice (young: P60-180; Middle-aged: P365-729; aged: 730+) for function and structural defects using electroretinograms, immunofluorescence, and phagocytosis assays.

Results: The largest changes in RPE morphology were evident between the young and aged groups, while the middle-aged group exhibited smaller but notable region-specific differences. We observed a 1.9-fold increase in cytoplasmic alpha-catenin expression specifically in the central-medial region of the eye between the young and aged group. There was an 8-fold increase in subretinal, IBA-1-positive immune cell recruitment and a significant decrease in visual function in aged mice compared to young mice. Functional defects in the RPE corroborated by changes in RPE phagocytotic capacity.

Conclusions: The marked increase of cytoplasmic alpha-catenin expression and subretinal immune cell deposition, and decreased visual output coincide with regional changes in RPE cell morphometrics when stratified by age. These cumulative changes in the RPE morphology showed predictive regional patterns of stress associated with loss of RPE integrity.

References

Ferrington D, Sinha D, Kaarniranta K . Defects in retinal pigment epithelial cell proteolysis and the pathology associated with age-related macular degeneration. Prog Retin Eye Res. 2015; 51:69-89. PMC: 4769684. DOI: 10.1016/j.preteyeres.2015.09.002. View

Fritsche L, Igl W, Cooke Bailey J, Grassmann F, Sengupta S, Bragg-Gresham J . A large genome-wide association study of age-related macular degeneration highlights contributions of rare and common variants. Nat Genet. 2015; 48(2):134-43. PMC: 4745342. DOI: 10.1038/ng.3448. View

Nasonkin I, Merbs S, Lazo K, Oliver V, Brooks M, Patel K . Conditional knockdown of DNA methyltransferase 1 reveals a key role of retinal pigment epithelium integrity in photoreceptor outer segment morphogenesis. Development. 2013; 140(6):1330-41. PMC: 3585665. DOI: 10.1242/dev.086603. View

Bumsted K, Barnstable C . Dorsal retinal pigment epithelium differentiates as neural retina in the microphthalmia (mi/mi) mouse. Invest Ophthalmol Vis Sci. 2000; 41(3):903-8. View

Ortolan D, Sharma R, Volkov A, Maminishkis A, Hotaling N, Huryn L . Single-cell-resolution map of human retinal pigment epithelium helps discover subpopulations with differential disease sensitivity. Proc Natl Acad Sci U S A. 2022; 119(19):e2117553119. PMC: 9171647. DOI: 10.1073/pnas.2117553119. View

Zhang N, Zhang X, Girardot P, Chrenek M, Sellers J, Li Y . Electrophysiologic and Morphologic Strain Differences in a Low-Dose NaIO3-Induced Retinal Pigment Epithelium Damage Model. Transl Vis Sci Technol. 2021; 10(8):10. PMC: 8287050. DOI: 10.1167/tvst.10.8.10. View

van Asten F, Simmons M, Singhal A, Keenan T, Ratnapriya R, Agron E . A Deep Phenotype Association Study Reveals Specific Phenotype Associations with Genetic Variants in Age-related Macular Degeneration: Age-Related Eye Disease Study 2 (AREDS2) Report No. 14. Ophthalmology. 2017; 125(4):559-568. PMC: 5866166. DOI: 10.1016/j.ophtha.2017.09.023. View

Biesemeier A, Yoeruek E, Eibl O, Schraermeyer U . Iron accumulation in Bruch's membrane and melanosomes of donor eyes with age-related macular degeneration. Exp Eye Res. 2015; 137:39-49. DOI: 10.1016/j.exer.2015.05.019. View

Gregory C, Converse C, Foulds W . Effect of glycoconjugates on rod outer segment phagocytosis by retinal pigment epithelial explants in vitro assessed by a specific double radioimmunoassay procedure. Curr Eye Res. 1990; 9(1):65-77. DOI: 10.3109/02713689009000056. View

10.

Jiang Y, Qi X, Chrenek M, Gardner C, Boatright J, Grossniklaus H . Functional principal component analysis reveals discriminating categories of retinal pigment epithelial morphology in mice. Invest Ophthalmol Vis Sci. 2013; 54(12):7274-83. PMC: 4086880. DOI: 10.1167/iovs.13-12450. View

11.

Wanner I, Anderson M, Song B, Levine J, Fernandez A, Gray-Thompson Z . Glial scar borders are formed by newly proliferated, elongated astrocytes that interact to corral inflammatory and fibrotic cells via STAT3-dependent mechanisms after spinal cord injury. J Neurosci. 2013; 33(31):12870-86. PMC: 3728693. DOI: 10.1523/JNEUROSCI.2121-13.2013. View

12.

Kemler R . From cadherins to catenins: cytoplasmic protein interactions and regulation of cell adhesion. Trends Genet. 1993; 9(9):317-21. DOI: 10.1016/0168-9525(93)90250-l. View

13.

Liu C, Wang Z, Sun Y, Chen J . Animal models of ocular angiogenesis: from development to pathologies. FASEB J. 2017; 31(11):4665-4681. PMC: 5636695. DOI: 10.1096/fj.201700336R. View

14.

Grossniklaus H, Nickerson J, Edelhauser H, Bergman L, Berglin L . Anatomic alterations in aging and age-related diseases of the eye. Invest Ophthalmol Vis Sci. 2013; 54(14):ORSF23-7. PMC: 3864374. DOI: 10.1167/iovs.13-12711. View

15.

Gullapalli V, Sugino I, Van Patten Y, Shah S, Zarbin M . Impaired RPE survival on aged submacular human Bruch's membrane. Exp Eye Res. 2005; 80(2):235-48. DOI: 10.1016/j.exer.2004.09.006. View

16.

Daruich A, Matet A, Moulin A, Kowalczuk L, Nicolas M, Sellam A . Mechanisms of macular edema: Beyond the surface. Prog Retin Eye Res. 2017; 63:20-68. DOI: 10.1016/j.preteyeres.2017.10.006. View

17.

Fritsche L, Chen W, Schu M, Yaspan B, Yu Y, Thorleifsson G . Seven new loci associated with age-related macular degeneration. Nat Genet. 2013; 45(4):433-9, 439e1-2. PMC: 3739472. DOI: 10.1038/ng.2578. View

18.

Kim Y, Yu H, Summers V, Donaldson K, Ferdous S, Shelton D . Morphometric Analysis of Retinal Pigment Epithelial Cells From C57BL/6J Mice During Aging. Invest Ophthalmol Vis Sci. 2021; 62(2):32. PMC: 7910641. DOI: 10.1167/iovs.62.2.32. View

19.

Xu H, Chen M, Forrester J . Para-inflammation in the aging retina. Prog Retin Eye Res. 2009; 28(5):348-68. DOI: 10.1016/j.preteyeres.2009.06.001. View

20.

Holz F, Bellmann C, Margaritidis M, Schutt F, Otto T, Volcker H . Patterns of increased in vivo fundus autofluorescence in the junctional zone of geographic atrophy of the retinal pigment epithelium associated with age-related macular degeneration. Graefes Arch Clin Exp Ophthalmol. 1999; 237(2):145-52. DOI: 10.1007/s004170050209. View