Intracellular calcium dynamics dependent on defined microtopographical features of titanium

Area of Science:

• Biomaterials Science
• Cell Biology
• Biophysics

Background:

• Cellular responses to biomaterial surface topography are key for implant integration.
• Microtopography influences cell adhesion structures like the actin cytoskeleton.
• The impact of microtopography on intracellular calcium signaling remains largely unknown.

Purpose of the Study:

• To investigate if artificial microtopography affects calcium ion (Ca(2+)) mobilization in osteoblasts.
• To elucidate the relationship between cell phenotype alterations and calcium signaling dynamics.

Main Methods:

• Human MG-63 osteoblast-like cells were cultured on silicon-titanium (Ti) arrays with pillar microtopography (P5) and planar Ti.
• Cells were stained with calcium dye Fluo 3-acetoxymethyl ester.
• Calcium signals were induced and measured upon adenosine 5'-triphosphate (ATP) stimulation.

Main Results:

• Osteoblasts on micropillars exhibited a shortened actin cytoskeleton.
• Calcium mobilization potential, in both signal height and duration, was reduced on micropillars.
• Basal intracellular Ca(2+) concentration and fibronectin synthesis were decreased on micropillars.
• Expression of specific voltage-sensitive calcium channels and signaling proteins remained unaffected.

Conclusions:

• Biomaterial surface microtopography significantly influences osteoblast calcium signaling dynamics.
• Altered actin cytoskeleton on micropillars correlates with impaired calcium mobilization and fibronectin synthesis.
• Topographical cues modulate cell function through intracellular calcium signaling pathways.