Page 126 - Physico-Chemical Niche Conditions for Bone Cells

Regulation of bone cell mitochondrial structure and dynamics
Mitochondria/F-actin filament movement
Before PFF treatment, pre-osteoblast mitochondrial distribution was flat and inactive as observed from side view. During PFF treatment, the apex height of the mitochondrial distribution first decreased, and then went back to its normal height (movie, DOI: 10.6084/m9.figshare.14459904). The dynamic movement process was showing alternating up and down movement (Fig. 5A; movie, DOI: 10.6084/m9.figshare.14459904). F-actin movement showed a similar pattern from side view. Before PFF treatment, the pre-osteoblast was spread well and appeared to be quite flat without showing any movement. During PFF treatment, the apex height of the pre-osteoblast (F-actin) was decreased (first cycle), followed by an increase (second cycle; movie, DOI: 10.6084/m9.figshare.14459904). This process showed alternating movement. From a top view, F-actin fibers could be clearly visualized (Fig. 5A; movie, DOI: 10.6084/m9.figshare.14459904). Without PFF, the green fluorescence area was relative wide (Fig. 5A). After the first cycle of PFF, F-actin fibers could still be observed clearly, but the green fluorescence area was decreased. After the second cycle of PFF, the fluorescence area increased again (Fig. 5A; movie, DOI: 10.6084/m9.figshare.14459904). This process also showed alternating movement. Based on the movies of mitochondria and F-actin, changes in apex height of a live pre-osteoblast subjected to PFF was determined (Fig. 5B). During PFF treatment, the cell with its mitochondria and F-actin moved up and down alternatingly.
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