Knochen und Entzündung

Zusammenfassung

Die Osteoporose ist gekennzeichnet durch geringe Knochendichte und mikroarchitektonische Veränderungen mit konsekutiv erhöhtem Frakturrisiko. Der Knochenumbau zeichnet sich durch ein ausgeglichenes Verhältnis zwischen Knochenresorption und Knochenaufbau aus. Auf zellulärer Ebene sind die Osteoblasten für den Knochenaufbau und die Osteoklasten für den Knochenabbau verantwortlich. Über ein fein abgestimmtes Zusammenspiel von molekularen Mechanismen, Zytokinen, Hormonen und Wachstumsfaktoren wird dabei die Knochenhomöostase gewährleistet. Das RANK/RANKL/OPG-System ist aktiv an der Reifung von Osteoklasten beteiligt und ihm kommt eine wichtige Rolle bezüglich der meisten pathophysiologischen Mechanismen bei der Osteoporose zu. Die vorliegende Übersichtsarbeit beschreibt die bekannten molekularen Mechanismen und pathophysiologischen Stoffwechselwege dieser Remodellingprozesse, insbesondere unter dem Einfluss von Entzündungsmediatoren und zeigt zukünftige innovative Therapieoptionen auf.

Summary

Osteoporosis is characterized by low bone mass and by changes in the microarchitecture of the bone with consecutive high risk for fractures. Bone remodelling is characterized by a balance between bone resorption and bone formation. The osteoblasts are responsible for bone synthesis and the osteoclasts for bone resorption. A finely adjusted interaction between molecular mechanisms leads, via cytokines, hormones and growth factors, to an homeostasis of the bone metabolism. The RANK/RANKL/OPG-system is actively involved in the differentiation and function of osteoclasts and seems to play a central role in most pathophysiological mechanisms that are active in osteoporosis. The present overview describes the known pathophysiological relevant metabolic pathways in this remodelling process especially the effect of inflammation on bone metabolism and present future innovative therapy options.

Schlüsselwörter

Knochenstoffwechsel - Remodelling - Osteoporose - RANK/RANKL/OPG

Keywords

Bone metabolism - remodelling - osteoporosis - RANK/RANKL/OPG

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