EC Orthopaedics

Osteocytes regulate homeostasis and bone turnover, exercise control over calcium and phosphate homeostasis, influence osteoblasts and osteoclasts activity, as well as acting as mechano-sensors in regulating bone responses. One of the substances expressed by Osteocytes is Sclerostin which acts by reducing bone formation through the inhibition of osteoblasts activity. Osteocytes play a role in the repair of bone microdamages by a remodeling of the damaged structure. This last effect is due to the ability to send signals that activate the expression of the nuclear factor RANKL and M-CSF which operate the recruitment and activation of OCs. Abnormalities in osteocytic morphology have been found in osteoporosis, osteoarthritic and osteomalacia bone. Alterations of the canalicular system affect the OCi signals and cause damage to the mechanical properties of the bone. The in-depth knowledge on the role of osteocytes has made it possible to tackle many skeletal pathologies with drugs aimed at influencing their activity and to envisage the possible development of osteometabolic new drugs.

 Keywords: Bone; Osteocytes; Metabolism; Sclerostin

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