Abstract: FR-PO0784
Transcription Factor ATOH8 Regulates Transforming Growth Factor (TGF)-β Signaling in Podocytes and Acts as a Key Protective Factor Against Glomerulosclerosis
Session Information
- Glomerular Diseases: Cell Homeostasis and Novel Injury Mechanisms
November 07, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1401 Glomerular Diseases: Mechanisms, including Podocyte Biology
Authors
- Hamatani, Hiroko, Gunma University Graduate School of medicine, Maebashi, Gunma, Japan
- Tabei, Akifumi, Fukaya Sekijuji Byoin, Fukaya, Saitama Prefecture, Japan
- Suwa, Junya, Gunma University Graduate School of medicine, Maebashi, Gunma, Japan
- Ogawa, Shinichiro, Gunma University Graduate School of medicine, Maebashi, Gunma, Japan
- Kinoshita, Masato, Gunma University Graduate School of medicine, Maebashi, Gunma, Japan
- Takeuchi, Yoichi, Gunma University Graduate School of medicine, Maebashi, Gunma, Japan
- Sakairi, Toru, Gunma University Graduate School of medicine, Maebashi, Gunma, Japan
- Ikeuchi, Hidekazu, Gunma University Graduate School of medicine, Maebashi, Gunma, Japan
- Kaneko, Yoriaki, Gunma University Graduate School of medicine, Maebashi, Gunma, Japan
- Hiromura, Keiju, Gunma University Graduate School of medicine, Maebashi, Gunma, Japan
Background
Atonal BHLH transcription factor 8 (ATOH8) is a basic helix-loop-helix (bHLH) transcription factor; however, its specific role in glomerular epithelial cells (podocytes) remains unclear. The study aimed to elucidate the function of ATOH8 in podocytes.
Methods
ATOH8 expression in mouse kidneys was analyzed using immunohistochemistry, immunofluorescence staining, and in situ hybridization. ATOH8 expression was knocked down in cultured human podocytes using shRNA, followed by RNA sequencing analysis. Adriamycin (ADR)-induced focal segmental glomerulosclerosis (FSGS) models were developed in Atoh8-deficient and wild-type mice for comparative analysis. In addition, ATOH8 expression was evaluated in the kidneys of rats, mice, and humans with nephropathy.
Results
ATOH8 was localized to a subset of podocytes in the mouse kidney. Transforming growth factor-beta (TGF-β) treatment significantly reduced ATOH8 mRNA expression in cultured human podocytes. RNA sequencing of shRNA-mediated ATOH8-knockdown podocytes revealed upregulation of extracellular matrix components and activation of TGF-β signaling. In ATOH8-knockdown cells, ATOH8 mRNA levels decreased to 0.16 (p = 0.005), while COL1A1, SNAI1, and VIM increased by 3.58-, 2.29-, and 1.55-fold, respectively (p < 0.006). These cells also exhibited SMAD2/3 nuclear translocation and a 2.43-fold increase in SMAD transcriptional activity, as determined by a luciferase assay (p = 0.0044), even in the absence of TGF-β stimulation, confirming constitutive activation of the TGF-β pathway.
At 10 weeks of age, Atoh8-deficient mice showed no overt renal abnormalities; however, following adriamycin-induced nephropathy, they developed significantly more pronounced glomerulosclerosis compared to wild-type mice (17.9% vs. 4.8%, p = 0.00005).
Decreased ATOH8 expression was also observed in ADR-induced FSGS models of wild-type mice and rats. In human kidney biopsies, ATOH8 expression was reduced by 60–76% in IgA nephropathy, diabetic kidney disease, ANCA-associated nephritis, and lupus nephritis compared to normal kidneys.
Conclusion
These findings suggest that ATOH8 suppresses TGF-β signaling in podocytes and may play a critical role as a protective factor against progression of glomerulosclerosis.
Funding
- Government Support – Non-U.S.