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Updated: Jul 4, 2025
Use of Animal Model of Sepsis to Evaluate Novel Herbal Therapies
Published on: April 11, 2012
MiR-145 Alleviates Sepsis-Induced Inflammatory Responses and Organ Injury by Targeting ADAM17
Yingying Lin1, Lizhen Liu2, Yao Lin1
1Jieyang Medical Research Center, Jieyang People's Hospital, 522000 Jieyang, Guangdong, China.
Background:
Current studies have demonstrated that disintegrin and metalloproteinase 17 (ADAM17) plays a critical role in the pathogenesis of sepsis. MicroRNA (miR)-145 is known to control immune responses as an anti-inflammatory modulatory molecule. However, a fundamental understanding of how miR-145 regulates ADAM17 and, more broadly, sepsis-induced inflammatory response remains unknown.
Methods:
We used western blotting and quantitative real-time PCR (qRT-PCR) to measure expression levels of ADAM17 and miR-145. Enzyme-linked immunosorbent assays (ELISA) were performed to measure cytokine production. To determine if ADAM17 is a target gene of miR-145, bioinformatics analyses and luciferase reporter assays were conducted. The impacts of ADAM17 and miR-145 on sepsis-induced inflammatory responses were accessed in vitro using human umbilical endothelial cells (HUVECs) treated with lipopolysaccharide (LPS). Sepsis-induced inflammatory response was measured in vivo using a polymicrobial septic mouse model induced by cecal ligation and puncture (CLP) with pre-injection of a miR-145 agomir.
Results:
In HUVECs treated with LPS, miR-145 expression was downregulated and miR-145 negatively regulated ADAM17 expression through direct binding to the ADAM17 transcript 3'-UTR. MiR-145 overexpression markedly reduced LPS-induced inflammatory cytokine production by targeting ADAM17 in HUVECs. In comparison to CLP-induced septic mice treated with a control agomir, treatment with a miR-145 agomir significantly reduced the expression of ADAM17, numerous downstream cytokines such as IL-6, TNF-α, IL-1β and MCP-1, and the endothelial injury factors ICAM-1, VCAM-1. The miR-145 agomir also alleviated acute lung and kidney injury and improved the survival rate of septic mice.
Conclusions:
This study showed that miR-145, by specifically targeting ADAM17, negatively regulates sepsis-induced inflammatory responses and vascular endothelial injury, and ultimately improved organ injury and survival during sepsis. The underlying mechanism for the regulation of ADAM17 expression by miR-145 and sepsis-induced inflammatory reactions may offer sepsis patients a novel therapeutic option.
Insights
MicroRNA-145 (miR-145) targets ADAM17 to reduce sepsis-induced inflammation and organ damage. This finding offers a potential new therapy for sepsis patients by modulating the miR-145/ADAM17 pathway.
Area of Science:
- Molecular Biology
- Immunology
- Pathophysiology
Background:
- Disintegrin and metalloproteinase 17 (ADAM17) is implicated in sepsis pathogenesis.
- MicroRNA-145 (miR-145) acts as an anti-inflammatory molecule, but its role in regulating ADAM17 and sepsis is unclear.
Purpose of the Study:
- To investigate the regulatory relationship between miR-145 and ADAM17.
- To determine the impact of miR-145 on sepsis-induced inflammatory responses and outcomes.
Main Methods:
- Western blotting, qRT-PCR, and ELISA were used to assess ADAM17, miR-145, and cytokine levels.
- Bioinformatics and luciferase reporter assays confirmed ADAM17 as a miR-145 target.
- In vitro (HUVECs) and in vivo (septic mouse model) experiments evaluated the effects of miR-145 modulation.
Main Results:
- miR-145 directly targets ADAM17, suppressing its expression.
- miR-145 overexpression reduced LPS-induced cytokine production and endothelial injury markers (ICAM-1, VCAM-1).
- In vivo, miR-145 agomir treatment decreased inflammatory cytokines, alleviated organ injury, and improved survival in septic mice.
Conclusions:
- miR-145 negatively regulates sepsis-induced inflammation and vascular injury by targeting ADAM17.
- Modulating the miR-145/ADAM17 pathway presents a potential therapeutic strategy for sepsis.
