Microgravity (MG) is known to induce bone loss in astronauts during long-duration space mission because of a lack of sufficient mechanical stimulation under MG. It has been demonstrated that mechanical signals are essential for maintaining cell viability and motility, and they possibly serve as a countermeasure to the catabolic effects of MG. The objective of this study was to examine the effects of high-frequency acoustic wave signals on osteoblasts in a simulated microgravity (SMG) environment (created using 1-D clinostat bioreactor) using a modified low-intensity pulsed ultrasound (mLIPUS). Specifically, the authors evaluated the hypothesis that osteoblasts (human fetal osteoblastic cell line) exposure to mLIPUS for 20 min/d at 30 mW/cm2 will significantly reduce the detrimental effects of SMG. Effects of SMG with mLIPUS were analyzed using the MTS proliferation assay for proliferation, phalloidin for F-actin staining, Sirius red stain for collagen, and Alizarin red for mineralization. The data showed that osteoblast exposure to SMG results in significant decreases in proliferation (∼ -38% and ∼ -44% on days 4 and 6, respectively; p < 0.01), collagen content (∼ -22%; p < 0.05) and mineralization (∼ -37%; p < 0.05) and actin stress fibers. In contrast, mLIPUS stimulation in SMG condition significantly increases the rate of proliferation (∼24% by day 6; p < 0.05), collagen content (∼52%; p < 0.05) and matrix mineralization (∼25%; p < 0.001) along with restoring formation of actin stress fibers in the SMG-exposed osteoblasts. These data suggest that the acoustic wave can potentially be used as a countermeasure for disuse osteopenia.
Reversal of the Detrimental Effects of Simulated Microgravity on Human Osteoblasts by Modified Low Intensity Pulsed Ultrasound
Umkehr der schädigenden Wirkung von simulierter Mikrogravität auf humane Osteoblasten mittels modifiziertem gepulstem Ultraschall mit geringer Intensität (LIPUS)
Ultrasound in Medicine and Biology ; 39 , 5 ; 804-812
2013
9 Seiten, 53 Quellen
Aufsatz (Zeitschrift)
Englisch
Effects of Simulated Microgravity on Expression of Integrin Subunits in Osteoblasts
British Library Conference Proceedings | 2008
|Microgravity Sensing, Mechano-Sensing and Osteoblasts
British Library Conference Proceedings | 2001
|Microgravity signal and stress response in rat osteoblasts during spaceflight
British Library Conference Proceedings | 2002
|Effects of simulated microgravity on cell cycle in human endothelial cells
Online Contents | 2014
|