Signaltransduktionswege der Mechanotransduktion in Knochenzellen

Zusammenfassung

Die Erhaltung der Knochenmasse wird durch die Interaktion von verschiedenen Faktoren, einschließlich systemischen Hormonen, lokalen Wachstumsfaktoren und mechanischer Belastung reguliert. Verantwortlich für die adaptive Antwort von Knochenzellen auf mechanische Belastung sind zelluläre Prozesse der Aufnahme, der Umwandlung des physikalischen Stimulus in strukturelle und biochemische Reaktionen, die als Mechanotransduktion bezeichnet werden. Osteoblasten und vor allem Osteozyten sind die mechanosensorischen Zellen des Knochens. Sie benötigen den mechanischen Stimulus für ihre Vitalität und Funktion. Die in der Mechanotransduktion aktivierten Signalwege wirken anabol auf die Knochenmasse. Hierzu gehören der WNT (wingless integration)/β-Catenin und der Östrogenrezeptor (ER)-Signalweg, die beide eine entscheidende Rolle in der Regulation von Knochenbildung und Knochenresorption spielen. Eine Aufklärung der Interaktion der Signalwege in der Mechanotransduktion durch geeignete In-vitro-und In-vivo-Experimente ist sinnvoll, um in Zukunft effektiv mechanische Signale in der Prävention und Intervention von/bei osteodegenerativen Krankheiten, wie z. B. Osteoporose, nutzen zu können.

Summary

Bone mass homeostasis is regulated by the interaction of various factors, including systemic hormones, local growth factors, and mechanical loading. Prerequisite for the adaptive response of bone cells to mechanical loading are mechanisms of perception and the transduction of mechanical signals into structural and biochemical processes in the cell, a phenomenon that is termed mechanotransduction. Osteoblasts, and in particular osteocytes, are the mechanosensitive cells in bone, and they require the mechanical stimulus for their vitality and function. The activation of signal transduction pathways in mechanotransduction results in an increase of bone mass. Two signal transduction pathways, the WNT (wingless integration)/β−catenin and the oestrogen receptor (ER) signal pathway, have been shown to play a crucial role in regulating bone formation and bone resorption. Studying signal pathways in mechanotransduction using in vitro and in vivo models is of significance for effective application of mechanical stimuli in the prevention of and the intervention in degenerative bone diseases, such as osteoporosis, in the future.

Schlüsselwörter

Mechanotransduktion - mechanische Belastung - WNT/β-Cateninund ÖstrogenrezeptorSignalweg - Knochenzellen

Keywords

Mechanotransduction - mechanical loading - WNT/β-catenin and estrogen receptor signaling pathway - bone cells

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