Date of Award
Medical Doctor (MD)
Purpose: ALDH3A1 is a corneal crystallin that causes a profound retardation in cell proliferation, decreased light scattering in vitro and protection against oxidative stress. Corneal injury decreases ALDH3A1 and triggers cell proliferation and the development of corneal haze due to increase light scattering. Our congenic Aldh3a1 knockout mice exhibit corneal haze. Our aim was to validate a recently generated Aldh3a1 knock-in (KI) mouse model, allowing us to study the non-catalytic functions of ALDH3A1, and to identify new pathways associated with ALDH3A1 using transcriptome analysis.
Methods: Western blot and enzyme activity for ALDH3A1 was performed to validate Aldh3a1 KI mouse model and RNA-seq analysis was performed in 3-6 month old WT and Aldh3a1 KO mice (N=4 per genotype). Differentially expressed genes in KO mice were identified as those with a minimum fold-change of +/− 2 and a Benjamini-Hochberg corrected p-value ≤0.05 relative to WT mice. Ingenuity® Pathway Analysis was used for pathway analyses.
Results: ALDH3A1 was expressed in Aldh3a1 KI mice, but found to be catalytically inactive, validating our model. In addition, RNA-seq analyses revealed 334 differentially regulated genes in Aldh3a1 KO mouse corneas, of which 73 are upregulated and 261 are downregulated (p < 0.05). Pathway analyses revealed neuroinflammation as the most activated pathway in Aldh3a1 KO mice, whereas inhibition of angiogenesis by TSP1 was the most inhibited pathway.
Conclusions: Our results extend our previous studies and support our hypotheses in demonstrating that ALDH3A1 may modulate lens cataractogenesis, corneal transparency, and corneal epithelium homeostasis by regulating cell cycle and metabolism. In addition, by influencing neuroinflammation and angiogenesis, ALDH3A1 may also have an important role in corneal susceptibility to bacterial/parasitic infections and corneal vascularization during graft-versus-host disease.
Apostolopoulos, Nicholas, "An Investigation Into The Role Of Aldehyde Dehydrogenase 3a1 (aldh3a1) In The Mouse Cornea" (2018). Yale Medicine Thesis Digital Library. 3373.