# Podocyte specific exon skipping after disease onset improves kidney pathology and function in a mouse model of Alport syndrome

**Authors:** Kentarou Hashikami, Ryosuke Kobayashi, Ryotaro Hori, Kenta Danbayashi, Yasunori Nio

PMC · DOI: 10.1038/s41598-025-25447-w · 2025-11-25

## TL;DR

A new mouse model shows that skipping a specific gene exon after disease onset can improve kidney function and pathology in Alport syndrome.

## Contribution

A tamoxifen-inducible, podocyte-specific exon-skipping model for Alport syndrome enables post-onset therapeutic evaluation.

## Key findings

- Exon skipping restored collagen IV α5 expression and improved kidney function in mice.
- Post-onset treatment reversed glomerular injury and ameliorated kidney pathology.
- The model supports the feasibility of exon-skipping therapies for monogenic kidney diseases.

## Abstract

Alport syndrome (AS) is a hereditary kidney disorder caused by mutations in COL4A3, COL4A4, and COL4A5, which often lead to progressive renal failure. Although angiotensin II receptor blockers are available for symptomatic treatment, no radical or curative therapies currently exist. Given the genetic basis of AS, exon-skipping therapy has the potential to serve as a definitive treatment. In this study, we established a tamoxifen-inducible exon 21–skipping mouse model, enabling the evaluation of post-onset therapeutic intervention. We generated a novel AS mouse model harboring a patient-derived nonsense mutation (R471*) in exon 21 of Col4a5 on a C57BL/6 background. Using this strain, we further developed a tamoxifen-inducible, podocyte-specific exon 21–skipping model. Induction of exon skipping, either before or after disease onset, restored truncated collagen IV α5 expression, improved renal function, and ameliorated glomerular and tubular pathology. Notably, treatment initiated after the onset of proteinuria reversed glomerular injury, underscoring its therapeutic potential even in progressive stages. This model provides a robust platform for evaluating mutation-targeted therapies and supports the feasibility of exon-skipping approaches for AS and other monogenic kidney diseases.

The online version contains supplementary material available at 10.1038/s41598-025-25447-w.

## Linked entities

- **Genes:** COL4A3 (collagen type IV alpha 3 chain) [NCBI Gene 1285], COL4A4 (collagen type IV alpha 4 chain) [NCBI Gene 1286], COL4A5 (collagen type IV alpha 5 chain) [NCBI Gene 1287], COL4A5 (collagen type IV alpha 5 chain) [NCBI Gene 1287]
- **Chemicals:** tamoxifen (PubChem CID 2733526)
- **Diseases:** Alport syndrome (MONDO:0018965), renal failure (MONDO:0001106), proteinuria (MONDO:0003634)

## Full-text entities

- **Genes:** Col4a3 (collagen, type IV, alpha 3) [NCBI Gene 12828] {aka [a]3(IV), alpha3(IV)}, Col4a5 (collagen, type IV, alpha 5) [NCBI Gene 12830], Col4a4 (collagen, type IV, alpha 4) [NCBI Gene 12829] {aka E130010M05Rik, [a]4(IV)}
- **Diseases:** AS (MESH:D009394), glomerular injury (MESH:D007674), renal failure (MESH:D051437), proteinuria (MESH:D011507), hereditary kidney disorder (MESH:D007680)
- **Chemicals:** tamoxifen (MESH:D013629)
- **Species:** Mus musculus (house mouse, species) [taxon 10090], Homo sapiens (human, species) [taxon 9606]
- **Mutations:** R471*
- **Cell lines:** /6 — Homo sapiens (Human), Tongue squamous cell carcinoma, Cancer cell line (CVCL_5985)

## Figures

6 figures with captions in the complete paper: https://tomesphere.com/paper/PMC12647216/full.md

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Source: https://tomesphere.com/paper/PMC12647216