Treatment With Methotrexate Associated With Lipid Core Nanoparticles Prevents Aortic Dilation in a Murine Model of Marfan Syndrome

Abstract

In Marfan syndrome (MFS), dilation, dissection, and rupture of the aorta occur. Inflammation can be involved in the pathogenicity of aortic defects and can thus be a therapeutic target for MFS. Previously, we showed that the formulation of methotrexate (MTX) associated with lipid nanoparticles (LDE) has potent anti-inflammatory effects without toxicity. To investigate whether LDEMTX treatment can prevent the development of aortic lesions in the MFS murine model. MgΔloxPneo MFS (n = 40) and wild-type (WT, n = 60) mice were allocated to 6 groups weekly injected with IP solutions of: (1) only LDE; (2) commercial MTX; (3) LDEMTX (dose = 1mg/kg) between 3rd and 6th months of life. After 12 weeks of treatments, animals were examined by echocardiography and euthanatized for morphometric and molecular studies. MFS mice treated with LDEMTX showed narrower lumens in the aortic arch, as well as in the ascending and descending aorta. LDEMTX reduced fibrosis and the number of dissections in MFS but not the number of elastic fiber disruptions. In MFS mice, LDEMTX treatment lowered protein expression of pro-inflammatory factors macrophages (CD68), T-lymphocytes (CD3), tumor necrosis factor-α (TNF-α), apoptotic factor cleaved-caspase 3, and type 1 collagen and lowered the protein expression of the transforming growth factor-β (TGF-β), extracellular signal-regulated kinases ½ (ERK1/2), and SMAD3. Protein expression of CD68 and CD3 had a positive correlation with an area of aortic lumen (r2 = 0.36; p < 0.001), suggesting the importance of inflammation in the causative mechanisms of aortic dilation. Enhanced adenosine availability by LDEMTX was suggested by higher aortic expression of an anti-adenosine A2a receptor (A2a) and lower adenosine deaminase expression. Commercial MTX had negligible effects. LDEMTX prevented the development of MFS-associated aortic defects and can thus be a candidate for testing in clinical studies.

Roles of pyroptosis and immune infiltration in aortic dissection

“…Among the multiple immune cells identified to be activated and infiltrated in AD, the infiltration of macrophages into the aortic wall is considered to be the main pathogenic mechanism of aortic injury ( Guido et al, 2022 ). Amorphous macrophages (M0 macrophages) are driven to differentiate into a pro-inflammatory (M1) or anti-inflammatory (M2) phenotype (also known as macrophage polarization) ( Xiao et al, 2020 ).…”

Inhibition of myeloperoxidase attenuates thoracic aortic aneurysm formation in Marfan disease

“…Accumulating evidence suggests the involvement of an inflammatory response in the pathogenesis of MFS. 18,37,[49][50][51][52][53] However, precise understanding of causes and consequences of inflammation and particularly the role of the innate immune system in MFS is lacking, and previous findings have not yet been translated to clinically available treatment strategies specifically targeting MFS-related immune responses. MPO is one of the most abundant proteins in neutrophils and critically involved in many cardiovascular diseases.…”