Possible role of Dickkopf-1 protein in the pathogenesis of tympanosclerosis in a rat model

Abstract Objectives: This study aimed to investigate the expression of DKK1 protein in an experimental model of tympanosclerosis and its possible role in the pathogenesis of this disorder. Methods: Forty Sprague Dawley rats were included in the study: 20 in the control group (which received no treatment) and 20 in the experimental group (which received an incision to induce tympanosclerosis). Otomicroscopy was performed to observe the development of myringosclerosis. Haematoxylin and eosin staining was performed to observe the morphological changes. Western blot analysis and immunohistochemistry were performed to assess the expression of DKK1 protein. Results: At day 15, sclerotic lesions were observed in 70 per cent of the tympanic membranes. Inflammatory infiltration and hyaline degeneration markedly appeared in the tympanic membranes and middle-ear mucosa. DKK1 protein was mainly distributed in the cytoplasm of epithelial cells, which were widely distributed in the tympanic membranes and middle-ear mucosa. The expression of DKK1 protein was significantly decreased in the calcified experimental ears. Conclusion: DKK1 protein is involved in the pathogenesis of tympanosclerosis by regulating the Wnt/β-catenin signalling pathway.