Authors: Tamás Karosi Péter Csomor Anita Szalmás József Kónya Mihály Petkó István Sziklai
Publish Date: 2010/10/21
Volume: 268, Issue: 3, Pages: 357-365
Abstract
Otosclerosis is a complex bone dystrophy of the human otic capsule leading to conductive and sensorineural hearing loss Since otosclerosis may at least in part be considered as an autoimmuneinflammatory disease disturbed balance of TNFalpha and osteoprotegerin OPG expression has been implicated in the pathological bone remodeling It has been supposed that active otosclerosis is characterized by decreased or missing local OPG production with invariable OPG sensitivity of the otosclerotic foci Ankylotic stapes footplates n = 41 removed by stapedectomy were processed to histological examination OPGspecific RTPCR tissue culturing and alkalinephosphatase AP activity assessment respectively OPG concentration of serum specimens n = 41 was measured by ELISA Cortical bone fragments harvested from the external ear canal were used as negative controls of otosclerosis Among 41 ankylotic stapes footplates 22 active and 19 inactive otosclerosis cases were histologically diagnosed OPG expression was significantly lower p 0001 in active otosclerosis compared to inactive cases Osteoclast cultures originated from active otosclerotic foci showed a considerable susceptibility against external OPG dosage which resulted in a significant decrease of AP activity p 0001 In contrast OPG serum levels were in the normal range 5–100 ng/ml indicating a nonsystemic bone resorption In conclusion secondary decreased local OPG production might play an important role in the pathogenesis of otosclerotic bone remodeling disorder As to previous and current results decreased OPG sensitivity of lesionforming cells should be excluded These observations may indicate the potential role of recombinant OPG treatment in early stages of otosclerosis
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