Moscatilin Inhibits Vascular Calcification by Activating IL13RA2-dependent Inhibition of STAT3 and Attenuating the Wnt3/β-catenin Signaling Pathway

Background

Vascular calcification is a pathological process involving the deposition of hydroxyapatite in the vessel wall, often associated with atherosclerotic cardiovascular disease and chronic kidney disease (CKD). Vascular calcification reduces the elasticity of the vessel wall, increasing the risk of cardiovascular events (such as plaque rupture) and affecting the outcomes of vascular reconstructive surgeries. Despite its association with various diseases, effective therapeutic drugs and strategies for vascular calcification remain limited. Therefore, finding effective treatments has become a major focus of current research.

Moscatilin (also known as Dendrophenol) is a natural compound extracted from Dendrobium huoshanense, a traditional Chinese medicinal herb, and exhibits various biological activities, such as enhancing immunity, anti-tumor effects, and anti-inflammatory properties. Recent studies suggest that Moscatilin may exert its biological effects by inhibiting inflammatory pathways. Given the close relationship between inflammation and vascular calcification, whether Moscatilin can inhibit vascular calcification by modulating inflammatory signaling pathways has become an area of interest.

Source of the Paper

This paper is a collaborative effort by research teams from Hefei University of Technology, University of Science and Technology of China, the University of Queensland (Australia), and the University of Vigo (Spain), among others. The first author is Tingting Zhang, and the corresponding authors are Suowen Xu and Yuanli Chen. The paper was published on February 27, 2024, in the Journal of Advanced Research, titled “Moscatilin inhibits vascular calcification by activating IL13RA2-dependent inhibition of STAT3 and attenuating the Wnt3/β-catenin signalling pathway.”

Research Process and Results

1. Research Design and Experimental Process

The core objective of the study was to explore the role of Moscatilin in inhibiting vascular calcification and its underlying mechanisms. The research was divided into the following steps:

• In vitro experiments: Researchers first established a high-phosphate-induced calcification model using human aortic smooth muscle cells (HASMCs). Through drug screening, Moscatilin was found to significantly reduce calcium deposition in HASMCs. Further transcriptomic analysis and cellular thermal shift assays (CETSA) revealed that Moscatilin binds to IL13RA2 and increases its expression, thereby inhibiting STAT3 activation.

• In vivo experiments: Researchers used C57BL/6J mice to establish a nicotine and vitamin D3 (VD3)-induced vascular calcification model. The mice were divided into a control group, a calcification model group, and a Moscatilin treatment group. Through tissue staining (e.g., Alizarin Red S staining, von Kossa staining) and calcium content measurements, Moscatilin was found to significantly reduce calcium deposition in the mouse aorta.

• Mechanistic studies: Using techniques such as Western blotting, immunofluorescence staining, and ELISA, researchers discovered that Moscatilin increases IL13RA2 expression, inhibits STAT3 activation, and attenuates the Wnt3/β-catenin signaling pathway, thereby suppressing osteogenic differentiation of HASMCs.

2. Key Experimental Results

• Moscatilin inhibits vascular calcification: In vitro experiments showed that Moscatilin significantly reduced calcium deposition in HASMCs and decreased the expression of osteogenic markers (e.g., ALPL, RUNX2, BMP2, and OPN). In vivo experiments demonstrated that Moscatilin significantly reduced calcium deposition in the mouse aorta.

• Role of IL13RA2 in Moscatilin’s anti-calcification effects: Transcriptomic analysis revealed that Moscatilin significantly increased IL13RA2 expression. Further CETSA experiments confirmed that Moscatilin binds to IL13RA2 and enhances its stability. siRNA-mediated inhibition of IL13RA2 expression partially reversed the anti-calcification effects of Moscatilin, indicating that IL13RA2 plays a critical role in Moscatilin’s anti-calcification mechanism.

• Role of STAT3 and the Wnt3/β-catenin signaling pathway: The study found that Moscatilin increases IL13RA2 expression, inhibits STAT3 activation, and attenuates the Wnt3/β-catenin signaling pathway. STAT3 overexpression or activation of the Wnt3/β-catenin pathway weakened the anti-calcification effects of Moscatilin.

3. Conclusions and Significance

This study demonstrates that Moscatilin inhibits vascular calcification by binding to and activating IL13RA2, thereby suppressing STAT3 activation and attenuating the Wnt3/β-catenin signaling pathway. This finding provides a new potential drug target for the treatment of vascular calcification. As a natural product, Moscatilin exhibits good safety and bioactivity, making it a promising candidate for treating vascular calcification.

4. Research Highlights

• Discovery of a novel anti-calcification drug: Moscatilin, a natural compound extracted from traditional Chinese medicine, was found for the first time to exhibit significant anti-vascular calcification effects.
• In-depth mechanistic studies: The study not only revealed the anti-calcification effects of Moscatilin but also detailed its mechanism of action through the IL13RA2/STAT3 and Wnt3/β-catenin signaling pathways.
• Validation across multiple models: The anti-calcification effects of Moscatilin were comprehensively validated through in vitro cell models, in vivo mouse models, and ex vivo aortic ring experiments.

Additional Valuable Information

The research team further validated the binding of Moscatilin to IL13RA2 and its direct regulation of STAT3 through molecular docking experiments and chromatin immunoprecipitation (ChIP) assays. These experiments provided robust evidence for the molecular mechanism of Moscatilin.

Summary

The findings of this study not only offer new insights into the treatment of vascular calcification but also highlight the potential applications of natural products in cardiovascular diseases. Moscatilin, by modulating the IL13RA2/STAT3 and Wnt3/β-catenin signaling pathways, demonstrates significant anti-calcification effects and holds promise as a novel therapeutic agent for vascular calcification.