Calcifying vascular smooth muscle cells and osteoblasts: independent cell types exhibiting extracellular matrix and biomineralization-related mimicries

Rationale: Extracellular matrix (ECM) remodeling is a key function of vascular smooth muscle cells (SMCs). MicroRNAs (miRNAs), in particular the miR-29 family and miR-195, have been implicated in the control of ECM secretion. Objective: To perform a proteomics comparison of miRNA effects on ECM production by vascular SMCs. Methods and Results: Murine SMCs were transfected with miRNA mimics and antimiRs of miR-29b and miR-195, and their conditioned medium was analyzed by mass spectrometry. Both miRNAs targeted a cadre of ECM proteins, including proteoglycans, collagens, proteases, elastin and proteins associated with elastic microfibrils, albeit miR-29 showed a stronger effect. The proteomics findings were subsequently validated at the transcription level using quantitative polymerase chain reaction. Similar to miR-29, in vivo inhibition of miR-195 by intraperitoneal injection of cholesterol bound antagomiRs led to significant alterations of elastin expression in murine aortas. Since elastin degradation is a key event in aortic aneurysm formation, we investigated miR-195 expression in patients. In human aortic aneurysmal tissue, miR-195 expression was reduced compared to non-aneurysmal tissue. In plasma, a comparison between male patients with abdominal aortic aneurysms and controls matched for diabetes and hypertension returned a panel of five highly correlated miRNAs: miR-195, miR-125b, miR-148a, miR-20a and miR-340 showed significant inverse associations with the presence of abdominal aortic aneurysms and aortic diameter, with miR-195 dominating in terms of association strength. Conclusions: Using proteomic analysis, we compared the effect of miR-29 and miR-195 on ECM secretion by vascular SMCs and identified novel miRNA targets. Findings in patients support an important role for miR-195 in vascular remodeling as evidenced by reduced miR-195 expression in human aneurysmal tissue and an inverse correlation between plasma miR-195 levels and aortic diameter.

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Vascular tissue engineering: microtextured scaffold templates to control organization of vascular smooth muscle cells and extracellular matrix

Acta Biomaterialia ◽

10.1016/j.actbio.2004.08.003 ◽

2005 ◽

Vol 1 (1) ◽

pp. 93-100 ◽

Cited By ~ 96

Author(s):

Sumona Sarkar ◽

Manisha Dadhania ◽

Patrick Rourke ◽

Tejal A. Desai ◽

Joyce Y. Wong

Keyword(s):

Tissue Engineering ◽

Extracellular Matrix ◽

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Vascular Smooth Muscle Cells ◽

Vascular Tissue ◽

Muscle Cells ◽

Vascular Tissue Engineering

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Spatially selective myosin regulatory light chain regulation is absent in dedifferentiated vascular smooth muscle cells but is partially induced by fibronectin and Klf4

AJP Cell Physiology ◽

10.1152/ajpcell.00251.2017 ◽

2019 ◽

Vol 316 (4) ◽

pp. C509-C521 ◽

Cited By ~ 2

Author(s):

Tsubasa S. Matsui ◽

Shinji Deguchi

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Smooth Muscle Cells ◽

Vascular Smooth Muscle Cells ◽

Light Chain ◽

Muscle Cells ◽

Cell Types ◽

Myosin Regulatory Light Chain ◽

Phosphorylation State ◽

Spatial Regulation

The phosphorylation state of myosin regulatory light chain (MRLC) is central to the regulation of contractility that impacts cellular homeostasis and fate decisions. Rho-kinase (ROCK) and myosin light chain kinase (MLCK) are major kinases for MRLC documented to selectively regulate MRLC in a subcellular position-specific manner; specifically, MLCK in some nonmuscle cell types works in the cell periphery to promote migration, while ROCK does so at the central region to sustain contractility. However, it remains unclear whether or not the spatially selective regulation of the MRLC kinases is universally present in other cell types, including dedifferentiated vascular smooth muscle cells (SMCs). Here, we demonstrate the absence of the spatial regulation in dedifferentiated SMCs using both cell lines and primary cells. Thus, our work is distinct from previous reports on cells with migratory potential. We also observed that the spatial regulation is partly induced upon fibronectin stimulation and Krüppel-like factor 4 overexpression. To find clues to the mechanism, we reveal how the phosphorylation state of MRLC is determined within dedifferentiated A7r5 SMCs under the enzymatic competition among three major regulators ROCK, MLCK, and MRLC phosphatase (MLCP). We show that ROCK, but not MLCK, predominantly regulates the MRLC phosphorylation in a manner distinct from previous in vitro-based and in silico-based reports. In this ROCK-dominating cellular system, the contractility at physiological conditions was regulated at the level of MRLC diphosphorylation, because its monophosphorylation is already saturated. Thus, the present study provides insights into the molecular basis underlying the absence of spatial MRLC regulation in dedifferentiated SMCs.

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