Synthesis and intracellular transportation of type I procollagen during functional differentiation of odontoblasts

Abstract

The expression of type I collagen, the most component of dentin extracellular matrix proteins (ECMs) in odontoblast is correlated with the activity of dentin formation. Since odontoblast possesses a distinct cellular process for protein transport into the dentinal tubule, it is important to examine the intracellular protein localization. However, a study focusing on odontoblast processes has not been performed. Type I collagen is synthesized as procollagen, which is immediately converted to collagen upon secretion. After characterization of antiserum to rat type I procollagen, we investigated the intracellular localization of type I procollagen in odontoblasts during and after dentinogenesis, using immunohistochemistry and in situ hybridization. The level of mRNA expression decreased during dentinogenesis, whereas the intracellular localization of type I procollagen in odontoblast processes become more distinct. The percentage of dentinal tubules with type I procollagen increased significantly with aging. Odontoblasts in pulp horn, in particular, showed moderate expression of type I procollagen after dentinogenesis. Since loss of occlusion also caused a significant decrease in type I procollagen, we concluded that occlusal stimulation activated type I procollagen synthesis in odontoblasts. We also suggest that analysis of intracellular transport of type I procollagen via odontoblast processes may be a new approach to evaluation of odontoblast function.

Wnt5a attenuates Wnt3a-induced alkaline phosphatase expression in dental follicle cells

“…After dehydration using a graded series of ethanol solutions and xylene, specimens were embedded in paraffin tissue blocks as previously described [32]. Serial paraffin sections (5 μm) containing the first molar root were treated with sodium citrate solution (10 mM, pH 6.0) in a microwave oven for 20 min for antigen retreaval.…”

Phosphonocarboxylates Can Protect Mice against the Inflammatory and Necrotic Side Effects of Nitrogen-Containing Bisphosphonates by Inhibiting Their Entry into Cells <i>via</i> Phosphate Transporters

“…Serial sections of 5-µm thickness were cut and used for immunohistochemistry, which was performed by following a previously reported protocol. 18) After deparaffinization, antigen retrieval was performed using proteinase K solution (Roche; 20 µg/ml in Tris-ethylenediaminetetraacetic acid (TE) buffer, pH 8.0) for 5 min at 37°C, and tissue sections were blocked for endogenous peroxidase activity with 0.3% hydrogen peroxide in methanol for 15 min at room temperature (r.t.). Sections were incubated at 4°C overnight with the primary antibody for SLC20a1 (dilution 1 : 1000; abcam, Cat.…”

The Bisphosphonates Clodronate and Etidronate Exert Analgesic Effects by Acting on Glutamate- and/or ATP-Related Pain Transmission Pathways

“…Serial sections of 5-µm thickness were cut and immunostaining was performed as described previously. 26) After deparaffinization, antigen retrieval was performed using proteinase K solution (20 µg/mL in TE buffer, pH 8.0) (Wako Pure Chemical Industries, Ltd.) for 5 min at 37°C. Then, tissue sections were blocked for endogenous peroxidase activity with 0.3% hydrogen peroxide in methanol for 15 min at room temperature.…”