Microvesicles from the plasma of elderly subjects and from senescent endothelial cells promote vascular calcification.
Alique M, Ruíz-Torres MP, Bodega G, Noci MV, Troyano N, Bohórquez L, Luna C, Luque R, Carmona A, Carracedo J, Ramírez R. Aging (Albany NY). 2017 Mar 8;9(3):778-789. PMID: 28278131
Matilde Alique (Spain)
1) Summarize your work in one sentence.
This work studied if microvesicles produced by senescent cultured endothelial cells, plus those found in the plasma of elderly subjects, promote calcification in vascular smooth muscle cells, thus testing the involvement of microvesicles produced by senescent endothelial cells and from plasma of elderly people in vascular calcification.
2) Summarize your findings in one sentence.
Our results provided mechanistic insights into the observed increase in vascular calcification-related diseases in the elderly, and in younger patients with premature vascular aging, paving the way towards novel therapeutic strategies.
3) Which were the more important methods you used in this work? If it is not a traditional method you can briefly explain the concept of that methodology.
We isolated microvesicles which are a subset of extracellular vesicles with a size between 0.5-1.5 µm across, from plasma (elderly and young subjects) and primary endothelial cell culture (young and senescent cells), using the quantification method previously published (International Society on Thrombosis and Haemostasis). Pooled microvesicles from each condition were characterized in terms of size and also with specific markers using flow cytometer. Moreover, we detected that microvesicles from senescent endothelial cells carry more calcium than young endothelial microvesicles by SEM/EDS (Scanning Electron Microscopy/Energy Dispersive X-Ray). Also, the content of these microvesicles carried calcium-binding annexins (A2 and A6) performed by western blot. Finally, we measured the capacity of these senescent endothelial microvesicles to generate calcifications in vascular smooth muscle cells using alizarin red staining.
4) What did you learn from this paper, what was your take-home message?
Aging is the main unmodifiable cardiovascular risk factor and increases the number of microvesicles in the plasma, more particularly endothelial microvesicles, promoting vascular calcification.