J Nutr Health.  2016 Feb;49(1):59-62. 10.4163/jnh.2016.49.1.59.

Role of zinc for calcification inhibitor protein in vascular smooth muscle cell plaque formation

• Shin MY
• Kwun IS

• KMID: 2158307
• DOI: http://doi.org/10.4163/jnh.2016.49.1.59

Abstract

PURPOSE
Zinc, a biomineral present within and outside cells, manages various cellular mechanisms. In this study, we examined whether zinc was involved in vascular smooth muscle cell (VSMC) calcification via regulation of calcification inhibitor protein, osteopontin (OPN).
METHODS
Rat aorta cell line (A7r5 cells) and primary vascular smooth muscle cells (pVSMCs) from rat aorta were cultured with phosphate (1-5 mM) and zinc (0-15 microM) as appropriate, along with osteoblasts (MC3T3-E1) as control. The cells were then stained for Ca and P deposition for calcification examination as well as osteopontin expression as calcification inhibitor protein was measured.
RESULTS
Both Ca and phosphate deposition increased as the addition of phosphate increased. In the same manner, the expression of osteopontin was upregulated as the addition of phosphate increased in both cell types. When zinc was added, Ca and P deposition decreased in VSMCs, while it increased in osteoblasts.
CONCLUSION
The results imply that zinc may prevent VSMC calcification by stimulating calcification inhibitor protein OPN synthesis in VSMCs.

Keyword

vascular smooth muscle cells; calcification; osteopontin; osteoblasts

MeSH Terms

Animals
Aorta
Cell Line
Muscle, Smooth, Vascular*
Osteoblasts
Osteopontin
Rats
Zinc*
Osteopontin
Zinc

Figure

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  Fig. 1 The addition of phosphate induced Ca (A) and P (B) deposition in vascular smooth muscle cells (pVSMCs and A7r5 cells) as well as in osteoblasts (MC3T3-E1 cells). Cells were cultured with the designated phosphate levels for 12 days and stained for Ca (A, in red) and P (B, in black) deposition.

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  Fig. 2 Calcification inhibitor protein, osteopontin, upregulated as the addition of P in creased in both VSMCs (A, A7r5) and osteoblasts (B, MC3T3-E1). Cells were cultured with the designated P level for 12 days.

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  Fig. 3 The addition of zinc prevented Ca and P accumulation in vascular smooth muscle cell A7r5 under calcified condition (A. at 3 and 5 mM P addition), while zinc stimulated Ca and P accumulation in osteoblasts. Cells were cultured with the designated Zn and phosphate level for 12 days.

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