Related Experiment Video
Updated: Jul 1, 2026

Modeling Cataract Surgery in Mice
Published on: December 1, 2023
TGFbeta promotes Wnt expression during cataract development
C C W Chong1, R J W Stump, F J Lovicu
1Save Sight Institute, The University of Sydney, Sydney NSW 2001, Australia.
Abstract:
TGFbeta induces lens epithelial cells to undergo epithelial mesenchymal transition (EMT) and many changes with characteristics of fibrosis including posterior capsular opacification (PCO). Consequently much effort is directed at trying to block the damaging effects of TGFbeta in the lens. To do this effectively it is important to know the key signaling pathways regulated by TGFbeta that lead to EMT and PCO. Given that Wnt signaling is involved in TGFbeta-induced EMT in other systems, this study set out to determine if Wnt signaling has a role in regulating this process in the lens. Using RT-PCR, in situ hybridization and immunolocalization this study clearly shows that Wnts 5a, 5b, 7b, 8a, 8b and their Frizzled receptors are upregulated in association with TGFbeta-induced EMT and cataract development. Both rat in vitro and mouse in vivo cataract models show similar profiles for the Wnt and Frizzled mRNAs and proteins that were assessed. Currently it is not clear if the canonical beta-catenin/TCF signaling pathway, or a non-canonical pathway, is activated in this context. Overall, the results from the current study indicate that Wnt signaling is involved in TGFbeta-induced EMT and development of fibrotic plaques in the lens.
Insights
Transforming growth factor beta (TGFbeta) triggers lens epithelial cells to undergo epithelial mesenchymal transition (EMT), a process implicated in fibrosis and posterior capsular opacification (PCO). This study reveals Wnt signaling is upregulated during TGFbeta-induced EMT in the lens, suggesting a role in cataract development.
Area of Science:
- Ophthalmology
- Cell Biology
- Molecular Biology
Background:
- Transforming growth factor beta (TGFbeta) is known to induce epithelial mesenchymal transition (EMT) in lens epithelial cells, leading to fibrotic changes and posterior capsular opacification (PCO).
- Understanding the signaling pathways regulated by TGFbeta is crucial for developing strategies to block its damaging effects in the lens.
- Wnt signaling pathways are implicated in TGFbeta-induced EMT in various cell types, prompting investigation into their role in the lens.
Purpose of the Study:
- To investigate the potential role of Wnt signaling in regulating TGFbeta-induced epithelial mesenchymal transition (EMT) and subsequent fibrotic changes in the lens.
- To determine if specific Wnt ligands and their Frizzled receptors are upregulated during TGFbeta-induced EMT and cataract development in ocular models.
Main Methods:
- Utilized reverse transcription-polymerase chain reaction (RT-PCR) to assess Wnt and Frizzled gene expression.
- Employed in situ hybridization to localize Wnt and Frizzled mRNAs within lens tissues.
- Used immunolocalization techniques to detect Wnt and Frizzled protein expression.
- Examined both rat in vitro and mouse in vivo cataract models.
Main Results:
- Demonstrated significant upregulation of Wnts 5a, 5b, 7b, 8a, 8b, and their corresponding Frizzled receptors in association with TGFbeta-induced EMT and cataract development.
- Observed similar expression profiles for Wnt and Frizzled mRNAs and proteins in both rat in vitro and mouse in vivo models.
- The study indicates that Wnt signaling is actively involved in the fibrotic processes occurring in the lens.
Conclusions:
- Wnt signaling pathways play a significant role in TGFbeta-induced epithelial mesenchymal transition (EMT) within the lens.
- The observed upregulation of Wnt ligands and Frizzled receptors suggests their involvement in the development of fibrotic plaques and posterior capsular opacification (PCO).
- Further research is needed to elucidate whether canonical (beta-catenin/TCF) or non-canonical Wnt pathways are activated in this context.
Related Concept Videos
Canonical Wnt Signaling Pathway
Canonical Wnt Signaling Pathway
Non-Canonical Wnt Signaling Pathways
Non-Canonical Wnt Signaling Pathways
Catenins
Catenins in Cell Junctions
Catenins bind to cell adhesion molecules such as cadherins and link them to different cytoskeletal proteins depending on the type of cell junction. At the adherens...
TGF - β Signaling Pathway
