Related Experiment Video
Updated: Jun 8, 2026
A Mouse Model for Laser-induced Choroidal Neovascularization
Published on: December 27, 2015
Microparticles carrying Sonic hedgehog favor neovascularization through the activation of nitric oxide pathway in
Tarek Benameur1, Raffaella Soleti, Chiara Porro
1CNRS, UMR 6214, INSERM, U771, Université d'Angers, Faculté de Médecine, Angers, France.
Background:
Microparticles (MPs) are vesicles released from plasma membrane upon cell activation and during apoptosis. Human T lymphocytes undergoing activation and apoptosis generate MPs bearing morphogen Shh (MPs(Shh+)) that are able to regulate in vitro angiogenesis.
Methodology/Principal Findings:
Here, we investigated the ability of MPs(Shh+) to modulate neovascularization in a model of mouse hind limb ischemia. Mice were treated in vivo for 21 days with vehicle, MPs(Shh+), MPs(Shh+) plus cyclopamine or cyclopamine alone, an inhibitor of Shh signalling. Laser doppler analysis revealed that the recovery of the blood flow was 1.4 fold higher in MPs(Shh+)-treated mice than in controls, and this was associated with an activation of Shh pathway in muscles and an increase in NO production in both aorta and muscles. MPs(Shh+)-mediated effects on flow recovery and NO production were completely prevented when Shh signalling was inhibited by cyclopamine. In aorta, MPs(Shh+) increased activation of eNOS/Akt pathway, and VEGF expression, being inhibited by cyclopamine. By contrast, in muscles, MPs(Shh+) enhanced eNOS expression and phosphorylation and decreased caveolin-1 expression, but cyclopamine prevented only the effects of MPs(Shh+) on eNOS pathway. Quantitative RT-PCR revealed that MPs(Shh+) treatment increased FGF5, FGF2, VEGF A and C mRNA levels and decreased those of α5-integrin, FLT-4, HGF, IGF-1, KDR, MCP-1, MT1-MMP, MMP-2, TGFβ1, TGFβ2, TSP-1 and VCAM-1, in ischemic muscles.
Conclusions/Significance:
These findings suggest that MPs(Shh+) may contribute to reparative neovascularization after ischemic injury by regulating NO pathway and genes involved in angiogenesis.
Insights
Microparticles bearing Shh (MPs(Shh+)) promote blood flow recovery in ischemic limbs by enhancing nitric oxide production and activating pro-angiogenic pathways. This effect is dependent on Shh signaling and suggests MPs(Shh+) as a therapeutic for neovascularization.
Area of Science:
- Regenerative Medicine
- Molecular Biology
- Cardiovascular Research
Background:
- Microparticles (MPs) are cell-derived vesicles involved in intercellular communication.
- MPs from activated T lymphocytes carry morphogen Shh (MPs(Shh+)) and influence angiogenesis in vitro.
- MPs(Shh+) represent a potential therapeutic for promoting tissue repair.
Purpose of the Study:
- To investigate the efficacy of MPs(Shh+) in promoting neovascularization in a mouse model of hind limb ischemia.
- To elucidate the underlying molecular mechanisms, including Shh signaling, nitric oxide (NO) production, and gene expression.
- To assess the role of Shh signaling inhibition on MPs(Shh+)-mediated effects.
Main Methods:
- In vivo treatment of mice with MPs(Shh+), vehicle, or cyclopamine (Shh inhibitor) for 21 days.
- Laser Doppler analysis to measure blood flow recovery.
- Analysis of Shh pathway activation, NO production, and expression of key angiogenic genes (e.g., eNOS, VEGF, FGF) in aorta and muscles.
- Quantitative RT-PCR to assess mRNA levels of various angiogenic and anti-angiogenic factors.
Main Results:
- MPs(Shh+) treatment significantly increased blood flow recovery (1.4-fold) in ischemic hind limbs.
- MPs(Shh+) enhanced NO production and activated the eNOS/Akt pathway in aorta and muscles.
- Shh inhibition with cyclopamine completely abolished the pro-angiogenic effects of MPs(Shh+).
- MPs(Shh+) modulated the expression of multiple genes involved in angiogenesis, including increased FGF and VEGF, and decreased anti-angiogenic factors.
Conclusions:
- MPs(Shh+) promote reparative neovascularization in ischemic injury models.
- The therapeutic effects are mediated through the regulation of the NO pathway and Shh signaling.
- MPs(Shh+) represent a promising cell-free therapeutic strategy for ischemic diseases.
Related Concept Videos
02:33Hedgehog Signaling Pathway
02:33Hedgehog Signaling Pathway