Adipose-derived stromal cell secreted factors induce the elastogenesis cascade within 3D aortic smooth muscle cell constructs

Aneesh K Ramaswamy; Rachel E Sides; Eoghan M Cunnane; Katherine L Lorentz; Leila M Reines; David A Vorp; Justin S Weinbaum

doi:10.1016/j.mbplus.2019.100014

Adipose-derived stromal cell secreted factors induce the elastogenesis cascade within 3D aortic smooth muscle cell constructs

Matrix Biol Plus. 2019 Sep 4:4:100014. doi: 10.1016/j.mbplus.2019.100014. eCollection 2019 Nov.

Authors

Aneesh K Ramaswamy¹, Rachel E Sides¹, Eoghan M Cunnane^{1

2}, Katherine L Lorentz¹, Leila M Reines¹, David A Vorp^{1

3

4

5

6}, Justin S Weinbaum^{1

3

7}

Affiliations

¹ Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States of America.
² Tissue Engineering Research Group, Department of Anatomy, Royal College of Surgeons in Ireland, Dublin, Ireland.
³ McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America.
⁴ Department of Surgery, University of Pittsburgh, Pittsburgh, PA, United States of America.
⁵ Department of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, PA, United States of America.
⁶ Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA, United States of America.
⁷ Department of Pathology, University of Pittsburgh, Pittsburgh, PA, United States of America.

Abstract

Objective: Elastogenesis within the medial layer of the aortic wall involves a cascade of events orchestrated primarily by smooth muscle cells, including transcription of elastin and a cadre of elastin chaperone matricellular proteins, deposition and cross-linking of tropoelastin coacervates, and maturation of extracellular matrix fiber structures to form mechanically competent vascular tissue. Elastic fiber disruption is associated with aortic aneurysm; in aneurysmal disease a thin and weakened wall leads to a high risk of rupture if left untreated, and non-surgical treatments for small aortic aneurysms are currently limited. This study analyzed the effect of adipose-derived stromal cell secreted factors on each step of the smooth muscle cell elastogenesis cascade within a three-dimensional fibrin gel culture platform.

Approach and results: We demonstrate that adipose-derived stromal cell secreted factors induce an increase in smooth muscle cell transcription of tropoelastin, fibrillin-1, and chaperone proteins fibulin-5, lysyl oxidase, and lysyl oxidase-like 1, formation of extracellular elastic fibers, insoluble elastin and collagen protein fractions in dynamically-active 30-day constructs, and a mechanically competent matrix after 30 days in culture.

Conclusion: Our results reveal a potential avenue for an elastin-targeted small aortic aneurysm therapeutic, acting as a supplement to the currently employed passive monitoring strategy. Additionally, the elastogenesis analysis workflow explored here could guide future mechanistic studies of elastin formation, which in turn could lead to new non-surgical treatment strategies.

Keywords: AA, aortic aneurysm; ACA, epsilon-amino caproic acid; ASC, adipose-derived stromal cell; ASC-SF, ASC secreted factors; Aneurysm; Aorta; ECM, extracellular matrix; Elastin; Extracellular matrix; FBS, fetal bovine serum; LOX, lysyl oxidase; LOXL-1, LOX-like 1; LTBP, latent TGF-β binding protein; NCM, non-conditioned media; NT, no treatment; PBS, phosphate buffered saline; RT, reverse transcriptase; SMC, smooth muscle cell; TGF-β, transforming growth factor-β; Vascular regeneration; qPCR, quantitative polymerase chain reaction.

Abstract

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