Inflammation-induced arterial dysfunction in atherosclerosis; the modulating action of mesenchymal stem cell-derived extracellular vesicles
Authors: Comarita IK , Constantin A , Vilcu A , Procopciuc A , Safciuc F , Alexandru N , Dragan E , Nemecz M , Filippi A , Georgescu A 
Published: June 2022

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – EU funding. Main funding source(s): CNCS-UEFISCDI

Background
Atherosclerosis is a progressive, chronic inflammatory disease of the large arteries caused by the constant accumulation of cholesterol, followed by endothelial dysfunction and vascular inflammation. We hypothesised that delivery of extracellular vesicles (EVs), recognized for their potential as therapeutic targets and tools, could restore vascular function in atherosclerosis.

Purpose
The goal was to evaluate vascular consequences of inflammation along with its key molecular and cellular players as intermediate endpoints for cardiovascular disease (CVD), and to explore ‘in vivo’ the potential beneficial effect of EVs from subcutaneous adipose tissue (EVs-ADSCs) or bone marrow mesenchymal stem cells (EVs-MSCs).

Methods
Our experimental animal model of atherosclerosis (hypertensive-hyperlipidemic hamster-HH) was treated with EVs-ADSCs or EVs-MSCs transfected or not with Smad2/3siRNA. For comparison, healthy animals (control group) or HH group transfected with Smad2/3siRNA alone were used.

Results
The results showed that compared with the control group, HH group displayed: (1) a marked increase of plasmatic parameter levels (cholesterol, LDL-cholesterol, triglycerides); (2) an amplification of expression of inflammatory markers with role in vascular dysfunction (COL1A, α-SMA, Cx43, VCAM-1, MMP-2); (3) a massive infiltration of total/M1 macrophages and T-cells into thoracic aorta and carotid artery; (4) an increased level of cytosolic ROS production; (5) a significant increase in plasma concentration of TGF-β1 and Ang II proteins; (6) significant structural (thickening of the arterial wall and reduction of the inner diameter) and functional changes (reduced distensibility, increased pulse wave velocity and velocity time integral, and diminished contractile responses to noradrenaline (NA) and reduced relaxation to acetylcholine (ACh)) in both thoracic aorta and carotid artery; (7) an altered protein expression profile (Smad2/3, ATF-2, NF-kBp50/p65) and a significant increase in the expression level of the miRNA panel (miR21, miR-29a, miR-192, miR-200b, miR-210, miR-146a) associated with inflammation-induced endothelial dysfunction. In addition, by comparison with the HH group, all treatment groups showed a significant decrease in the levels of plasma parameters, but also a noticeable improvement in the structure and function of the investigated blood vessels along with a decrease in the key molecules that modulate the inflammatory response through soluble mediators and cellular components.

Conclusion
We can conclude that the administration for 4 months of atherogenic diet activated key regulatory molecules in the atherosclerotic process, respectively TGF-β1, Ang II and ROS, modulating main orchestrators of inflammation-mediated atherosclerotic CVD progression. Also, EV-based treatment of inflammation, especially the EV-ADSC-based one, led to regression of arterial dysfunction and its key molecular players.