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Ac-SDKP modulates apoptosis via HSP27 and the FAS/FASL and mitochondrial axes
Wenxin Guo1,2, Jinyin Yan3, Wenli Li1,2
1School of Basic Medical Sciences, North China University of Science and Technology, Tangshan, China.
Animal Models and Experimental Medicine
|August 6, 2026
Summary
The anti-fibrotic tetrapeptide Ac-SDKP modulates apoptosis via heat shock protein 27 (HSP27) in silicosis. Targeting HSP27 may restore apoptotic-fibrotic balance in lung fibrosis.
Area of Science:
- Pulmonary Medicine
- Cell Biology
- Fibrotic Lung Disease Research
Background:
- Silicosis is a progressive lung fibrosis from crystalline silica exposure.
- The anti-fibrotic tetrapeptide Ac-SDKP shows therapeutic potential.
- Mechanisms of Ac-SDKP in silica-induced lung injury, particularly HSP27's role in apoptosis, require clarification.
Purpose of the Study:
- Investigate Ac-SDKP's modulation of apoptosis in silicosis.
- Elucidate the role of heat shock protein 27 (HSP27) in this process.
- Explore therapeutic strategies targeting HSP27 for pulmonary fibrosis.
Main Methods:
- In vivo studies using Wistar rats with silica exposure, treated with Ac-SDKP.
- In vitro experiments with MEF and A549 cells treated with TGF-β1 and Ac-SDKP.
- Utilized HSP27 interference vectors to assess apoptosis pathways (FAS/FASL, mitochondrial).
Main Results:
- Ac-SDKP alleviated pulmonary fibrosis and reduced apoptosis in vivo.
- In vitro, Ac-SDKP restored apoptosis suppressed by TGF-β1 via HSP27-mediated pathways.
- HSP27 knockdown enhanced apoptosis and reduced fibrosis in vivo, confirming its anti-apoptotic role.
Conclusions:
- Ac-SDKP context-dependently modulates apoptosis via HSP27.
- HSP27 protects lung cells in vivo but promotes survival in vitro.
- Targeting HSP27 offers a potential therapeutic strategy for silicosis and related fibrotic disorders.
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