Peroxisome Proliferator-Activated Receptor γ Agonist Rosiglitazone Protects Blood-Brain Barrier Integrity Following Diffuse Axonal Injury by Decreasing the Levels of Inflammatory Mediators Through a Caveolin-1-Dependent Pathway - PubMed (original) (raw)

Peroxisome Proliferator-Activated Receptor γ Agonist Rosiglitazone Protects Blood-Brain Barrier Integrity Following Diffuse Axonal Injury by Decreasing the Levels of Inflammatory Mediators Through a Caveolin-1-Dependent Pathway

Yonglin Zhao et al. Inflammation. 2019 Jun.

Abstract

Our early experiments confirmed that rosiglitazone (RSG), a peroxisome proliferator-activated receptor γ (PPARγ) agonist, had therapeutic potential for the treatment of diffuse axonal injury (DAI) by inhibiting the expression of amyloid-beta precursor protein and reducing the loss and abnormal phosphorylation of tau, but the underlying mechanisms were not fully defined. In this study, we aimed to investigate a possible role for PPARγ in the protection of blood-brain barrier (BBB) integrity in a rat model of DAI, and the underlying mechanisms. PPAR agonists and antagonists were intraperitoneally injected after DAI. Treatment with RSG ameliorated axonal injury, cell apoptosis, glia activation, and the release of inflammatory factors such as TNF-α, IL-1β, and IL-6. It also increased the expression of tight junction-associated proteins like ZO-1, claudin-5, and occludin-1, whereas the PPARγ antagonist GW9662 had the opposite effects. These effects were also studied in a BBB in vitro model, consisting of a monolayer of human microvascular endothelial cells (HBMECs) subjected to oxygen and glucose deprivation (OGD). Treatment with RSG ameliorated the loss of BBB integrity and the increased permeability induced by OGD by reducing the release of inflammatory factors and maintaining the expression of tight junction-associated proteins. Interestingly, caveolin-1 was found located mainly in endothelial cells, and RSG increased the expression of caveolin-1, which decreased following OGD. In contrast, caveolin-1 siRNA abrogated the protective effects of RSG in the in vitro BBB model. In conclusion, we provide evidence that PPARγ plays an important role in a series of processes associated with DAI, and that the PPARγ agonist RSG can protect BBB integrity by decreasing the levels of inflammatory mediators through a caveolin-1-dependent pathway.

Keywords: Blood–brain barrier; Caveolin-1; Diffuse axonal injury; Peroxisome proliferator-activated receptor γ.

PubMed Disclaimer

Similar articles

Cited by

References

    1. J Neurotrauma. 2014 Mar 1;31(5):505-14 - PubMed
    1. Mol Med Rep. 2015 Nov;12(5):6591-7 - PubMed
    1. Front Biosci (Schol Ed). 2011 Jun 01;3:1216-31 - PubMed
    1. Mech Dev. 2015 Nov;138 Pt 1:8-16 - PubMed
    1. Brain Res. 2013 Jun 4;1513:1-8 - PubMed

MeSH terms

Substances

LinkOut - more resources