TY - JOUR
T1 - Pulsating fluid flow affects pre-osteoblast behavior and osteogenic differentiation through production of soluble factors
AU - Jin, Jianfeng
AU - Seddiqi, Hadi
AU - Bakker, Astrid D.
AU - Wu, Gang
AU - Verstappen, Johanna F. M.
AU - Haroon, Mohammad
AU - Korfage, Joannes A. M.
AU - Zandieh-Doulabi, Behrouz
AU - Werner, Arie
AU - Klein-Nulend, Jenneke
AU - Jaspers, Richard T.
N1 - © 2021 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.
PY - 2021/6
Y1 - 2021/6
N2 - Bone mass increases after error-loading, even in the absence of osteocytes. Loaded osteoblasts may produce a combination of growth factors affecting adjacent osteoblast differentiation. We hypothesized that osteoblasts respond to a single load in the short-term (minutes) by changing F-actin stress fiber distribution, in the intermediate-term (hours) by signaling molecule production, and in the long-term (days) by differentiation. Furthermore, growth factors produced during and after mechanical loading by pulsating fluid flow (PFF) will affect osteogenic differentiation. MC3T3-E1 pre-osteoblasts were either/not stimulated by 60 min PFF (amplitude, 1.0 Pa; frequency, 1 Hz; peak shear stress rate, 6.5 Pa/s) followed by 0-6 h, or 21/28 days of post-incubation without PFF. Computational analysis revealed that PFF immediately changed distribution and magnitude of fluid dynamics over an adherent pre-osteoblast inside a parallel-plate flow chamber (immediate impact). Within 60 min, PFF increased nitric oxide production (5.3-fold), altered actin distribution, but did not affect cell pseudopodia length and cell orientation (initial downstream impact). PFF transiently stimulated Fgf2, Runx2, Ocn, Dmp1, and Col1⍺1 gene expression between 0 and 6 h after PFF cessation. PFF did not affect alkaline phosphatase nor collagen production after 21 days, but altered mineralization after 28 days. In conclusion, a single bout of PFF with indirect associated release of biochemical factors, stimulates osteoblast differentiation in the long-term, which may explain enhanced bone formation resulting from mechanical stimuli.
AB - Bone mass increases after error-loading, even in the absence of osteocytes. Loaded osteoblasts may produce a combination of growth factors affecting adjacent osteoblast differentiation. We hypothesized that osteoblasts respond to a single load in the short-term (minutes) by changing F-actin stress fiber distribution, in the intermediate-term (hours) by signaling molecule production, and in the long-term (days) by differentiation. Furthermore, growth factors produced during and after mechanical loading by pulsating fluid flow (PFF) will affect osteogenic differentiation. MC3T3-E1 pre-osteoblasts were either/not stimulated by 60 min PFF (amplitude, 1.0 Pa; frequency, 1 Hz; peak shear stress rate, 6.5 Pa/s) followed by 0-6 h, or 21/28 days of post-incubation without PFF. Computational analysis revealed that PFF immediately changed distribution and magnitude of fluid dynamics over an adherent pre-osteoblast inside a parallel-plate flow chamber (immediate impact). Within 60 min, PFF increased nitric oxide production (5.3-fold), altered actin distribution, but did not affect cell pseudopodia length and cell orientation (initial downstream impact). PFF transiently stimulated Fgf2, Runx2, Ocn, Dmp1, and Col1⍺1 gene expression between 0 and 6 h after PFF cessation. PFF did not affect alkaline phosphatase nor collagen production after 21 days, but altered mineralization after 28 days. In conclusion, a single bout of PFF with indirect associated release of biochemical factors, stimulates osteoblast differentiation in the long-term, which may explain enhanced bone formation resulting from mechanical stimuli.
KW - F-actin stress fiber
KW - finite element modeling
KW - fluid dynamics
KW - osteogenic differentiation
KW - pre-osteoblast
U2 - 10.14814/phy2.14917
DO - 10.14814/phy2.14917
M3 - Article
C2 - 34174021
SN - 2051-817X
VL - 9
SP - 1
EP - 18
JO - Physiological Reports
JF - Physiological Reports
IS - 12
M1 - e14917
ER -