No abstract

Our findings support a role for TGFbeta in the physiological and pathological effects of RA on inner ear development.

The transforming growth factor-beta (TGF-beta) superfamily, including TGF-beta1 and bone morphogenetic protein (BmP2, BmP4), participates in the regulation of the developing cartilaginous otic capsule, which prefigures the endochondral bony labyrinth of the inner ear. This study investigates Smad-6 and -7, downstream components of the TGF-beta/BMP signaling pathway, in otic capsule chondrogenic control, and supports a function for these inhibitory Smads as negative regulators of capsule chondrogenesis. The importance of otic capsule chondrogenic control and implications of Smad signaling for otosclerosis, a disease affecting the endochondral bony labyrinth, are indicated.

Rates of activation can be accelerated with the addition of stem cells and growth factors to distraction sites, as could time to full consolidation. The addition of mesenchymal stem cells and deferoxamine and the use of low-intensity ultrasound during distraction are three of the most promising approaches reported in recent studies with potential for future translation from animal models. Computer-assisted presurgical planning offers added accuracy and potential time savings. Newer distraction devices using computer automation are still in preliminary phases, but show promise.