Method: Gingival tissue samples were obtained from patients undergoing hypertension therapy with NIF (n=5), and control patients (n=4) who are systematically healthy. Tissues were examined, via immunohistochemistry, for periostin and αSMA proteins. Cultured healthy gingival fibroblasts were treated with NIF (30 ng/ml and 100 ng/ml) then RT-PCR and Western blotting were used to analyze changes in periostin expression. Changes in αSMA expression, as well as FAK and ERK1/2 activations were also examined using western blotting.
Result: All the diseased tissues demonstrated markedly increased periostin immunoreactivity compared to the healthy tissues, particularly in the ECM-rich, deep connective tissue. Furthermore, both periostin mRNA (p < 0.05) and protein expression increased in gingival fibroblasts cultured with NIF. NIF also increases αSMA expression and ERK1/2 activation of the cultured fibroblasts in vitro. However, ERK1/2 inhibition did not attenuate NIF-induced αSMA expression.
Conclusion: These results show that NIF directly induces periostin and αSMA expression in gingival fibroblasts. Considering periostin’s role in other fibrotic diseases and its over-expression in NIGF, this study may suggest a new therapeutic target for blocking development of gingival overgrowth.
Keywords: Extracellular matrix molecules, Fibroblasts, Fibrosis, Molecular biology and Periodontal disease
See more of: Periodontal Research - Pathogenesis