Cyclic Hydrostatic Pressure Suppresses Osteogenic Differentiation via Actomyosin Contractility
Takashi Miyano1, Toshihiro Sera1
1Department of Medical and Robotic Engineering Design, Tokyo University of Science, Tokyo, Japan.
Cellular and Molecular Bioengineering
|December 2, 2025
Summary
Cyclic hydrostatic pressure (HP) more significantly inhibits osteogenic differentiation in periodontal ligament cells than static HP. This effect is mediated by increased actomyosin contractility, highlighting the role of mechanical stress in regulating bone formation.
Area of Science:
- Biomaterials Science
- Cell Biology
- Tissue Engineering
Background:
- The periodontal ligament (PDL) resists mineralization despite its location between mineralized tissues.
- The influence of mechanical forces, like cyclic hydrostatic pressure (HP) during mastication, on PDL osteogenic potential is unclear.
Purpose of the Study:
- To compare the effects of static and cyclic HP on osteogenic differentiation.
- To investigate the underlying mechanisms, particularly actomyosin contractility.
Main Methods:
- MC3T3-E1 pre-osteoblastic cells were subjected to static or cyclic HP using a custom device.
- Osteogenic differentiation was assessed via alkaline phosphatase (ALP) activity.
- Actomyosin contractility was evaluated using vinculin and phosphorylated myosin light chain (p-MLC) staining.
- Myosin II inhibition was achieved using blebbistatin.
Main Results:
- Cyclic HP (0.2 Hz) more potently inhibited ALP activity than static HP (5 MPa).
- HP increased focal adhesion and p-MLC levels, with cyclic HP showing a greater increase.
- Blebbistatin treatment attenuated HP-induced inhibition of osteogenic differentiation, confirming the role of actomyosin contractility.
Conclusions:
- Cyclic HP suppresses osteogenic differentiation more effectively than static HP in pre-osteoblastic cells.
- Enhanced actomyosin contractility, indicated by increased p-MLC, mediates this suppression.
Related Concept Videos
01:10The Role of Actin and Myosin in Non-muscle Cells
4.5K
Actin and myosin or actomyosin filaments also play a significant role in cells other than those involved in muscle contraction (which occurs within the sarcomere of muscle cells). The mechanism of non-muscle cell contractile bundles was first observed in Dictyostelium and Acanthamoeba. In non-muscle cells, two bundles are commonly found: stress fibers and actomyosin adherence belts. These contractile bundles are smaller and less organized than the ones found in muscle cells. They are held...
4.5K
01:17Hormones and Bone Tissue
3.6K
The endocrine system produces and secretes hormones, which interact with the skeletal system. These hormones control bone growth, maintain bone once it is formed, and remodel it.
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
3.6K
01:31Osteoclasts in Bone Remodeling
3.8K
Osteoclasts are cells responsible for bone resorption and remodeling. They originate from hematopoietic progenitor cells present in the bone marrow. Numerous progenitor cells fuse to form multinucleated cells, each with 10-20 nuclei. A single osteoclast has a diameter of 150 to 200 µM. These cells have ruffled borders that break down the underlying bone tissue and release minerals such as calcium into the blood in bone resorption. Osteoclasts cling to bones with their ruffled edges during...
3.8K
01:40Bone Remodeling
40.2K
Bone remodeling is a continuous and balanced process of bone resorption by osteoclasts and bone formation by osteoblasts. In adults, it helps maintain bone mass and calcium homeostasis. While mechanical stress can stimulate turnover as part of the normal maintenance and reparative process, several hormones also regulate bone remodeling.
40.2K
01:25Smooth Muscle Contraction
7.1K
Smooth muscle contraction is a complex process vital for various bodily functions, from maintaining blood vessel tension to facilitating the movement of food through the digestive tract. Unlike striated muscles, smooth muscle contraction begins more slowly and lasts longer.
The onset of contraction is triggered by an increase in calcium ions within the sarcoplasm, similar to the process in striated muscle. However, smooth muscles have a relatively smaller reservoir of the sarcoplasmic...
The onset of contraction is triggered by an increase in calcium ions within the sarcoplasm, similar to the process in striated muscle. However, smooth muscles have a relatively smaller reservoir of the sarcoplasmic...
7.1K
01:27Feedback Regulation of Calcium Concentration
3.9K
Calcium is an essential signaling molecule required for various cellular functions. Calcium pumps and ion channels on cell and organellar membranes, such as those on the endoplasmic reticulum (ER), regulate calcium concentrations inside the cell. They remain closed, keeping the cytosolic calcium levels low at a resting state.
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
3.9K