Expression and Function of the Actin-severing Protein Adseverin in the Proliferation, Migration, and Differentiation of Dental Pulp Cells

• We examine the expression and location of adseverin in DPCs and rat tooth germs.
• Adseverin acts as an F-actin regulator during odontoblastic differentiation.
• Knockdown of adseverin decreases the odontoblastic differentiation of DPCs.
• The mechanism may rely on the actin cytoskeleton mediated by adseverin.

IntroductionAdseverin is an actin-severing and actin-capping protein that is primarily expressed in secretory cells, where it regulates the filamentous actin cytoskeleton during cell differentiation and exocytosis. However, little is known regarding its regulatory role in dental pulp cells (DPCs). This study examined the expression and function of adseverin in the proliferation, migration, and odontoblastic differentiation of DPCs.MethodsDPCs were assayed for morphologic changes, proliferation, migration, alkaline phosphatase activity, and dentin sialoprotein and dentin matrix protein-1 protein levels in vitro after knockdown of adseverin by using small interfering RNA. Tooth germs isolated from Sprague-Dawley rats were processed for immunohistochemistry analysis of adseverin.ResultsAdseverin expression was increased in a time-dependent fashion in the early stage of odontoblastic differentiation. When adseverin expression was suppressed in DPCs, their cellular morphology was altered, and their proliferation, migration, and odontoblastic differentiation were substantially decreased in vitro. Secretory odontoblasts in the tooth germ at day 5 post partum expressed a stronger adseverin signal compared with those at days 1 and 3 post partum.ConclusionsAdseverin may play a crucial role in the proliferation, migration, and odontoblastic differentiation of DPCs via filamentous actin cytoskeleton regulation. However, further investigations are required to clarify the underlying mechanisms.