J Nutr Health.  2020 Aug;53(4):347-355. 10.4163/jnh.2020.53.4.347.

Zinc modulation of osterix in MC3T3-E1 cells

• Seo HJ
• Jeong JB
• Cho YE
• Kwun IS

• KMID: 2506197
• DOI: http://doi.org/10.4163/jnh.2020.53.4.347

Abstract

Purpose
Zinc is known to be associated with osteoblast proliferation and differentiation. Osterix as zinc-finger transcription factor is also related to osteoblast differentiation and bone formation. In the present study, we aimed to investigate whether zinc modulates osterix gene and protein expression in osteoblastic MC3T3-E1 cells.
Methods
MC3T3-E1 cells were cultured in zinc-dependent concentrations (0, 0.5, 1, 5, or 15 µM Zn), along with osteogenic control (normal osteogenic medium) for 1 and 3 days. The gene and protein expression levels of osterix were analyzed by real-time reverse transcription polymerase chain reaction and Western blotting, respectively.
Results
Zinc increased osteoblast proliferation in a concentration-dependent manner at day 1 and 3. Similarly, zinc increased the activity of osteoblast marker enzyme alkaline phosphatase in cells and media in a zinc concentration-dependent manner. Moreover, our results showed that the pattern of osterix gene expression by zinc was down-regulated within the low levels of zinc treatments (0.5–1 µM) at day 1, but it was up-regulated after extended culture period at day 3. Osterix protein expression by zinc showed the similar pattern of gene expression, which down-regulated by low zinc levels at day 1 and up-regulated back at day 3 as the early stage of osteoblast differentiation.
Conclusion
Our results suggest that zinc modulates osterix gene and protein expression in osteoblasts, particularly in low level of zinc at early stage of osteoblast differentiation period.

Keyword

zinc; osterix; MC3T3-E1 cells; osteoblast differentiation