[IPROSI-2] Electrically Charged Tissue-Nonspecific Alkaline Phosphatase Promotes Periodontal Tissue Regeneration for an Optimal Fixed Prosthodontics Treatment
[Abstract]
[Objective]
Maintaining crown-root ratio by cementum and alveolar bone is critical to the success of fixed prosthodontics treatment. Tissue-nonspecific alkaline phosphatase (TNAP), an isoenzyme of alkaline phosphatase (ALP), promotes biological apatite crystallization1). An acidic oligopeptide-tagging approach generated negatively charged TNAP, resulting in more efficient delivery to positively charged mineralized tissue2). Bone sialoprotein knockout (Ibsp-/-) mice exhibit unique phenotype mimicking periodontitis1). This study aimed to determine the effects of TNAP tagged with aspartic acid residues (Asp; Asp-TNAP) on periodontal tissue regeneration.
[Method]
TNAP was generated by removing glycosylphosphatidylinositol-anchoring signal peptide sequence and adding export signal in TNAP sequence. A negatively charged TNAP was provided by adding six Asp codons at C-terminus (Asp6-TNAP). In vitro study was conducted using murine cementoblast-like cell line (OCCM.30) to assess the mineralization effects of Asp6-TNAP with Alizarin Red staining. Ibsp-/- and wild type (WT) mice with mandibular bone defects were locally administered Asp6-TNAP. Histomorphological analyses were performed including micro-computed tomography and histological staining.
[Results and Discussion]
Asp6-TNAP was successfully generated, and ALP enzyme activity was confirmed, suggesting that acidic oligopeptide-tagging approach did not affect enzyme function. Asp6-TNAP promoted mineralization in OCCM.30 cells in WT and Ibsp-/- (4-fold and 11-fold, respectively, compared with control), and these effects were inhibited by TNAP inhibitor. Asp6-TNAP increased alveolar bone volume and mineral density (50 % and 10 %, respectively). Asp6-TNAP significantly induced cementum-like structure formation on the root surface and induced periodontal ligament attachment. These results suggest that Asp6-TNAP substantially promotes periodontal tissue regeneration. Electrically charged TNAP is a promising therapeutic agent that can be applied for adequate tooth abutment and alveolar augmentation for successful prosthodontics treatment.
[References]
1) Nagasaki A, Nagasaki K, Kear BD, et al. Delivery of alkaline phosphatase promotes periodontal regeneration in mice. J Dent Res 2021;100(9):993-1001.
2) Nishioka T, Tomatsu S, Gutierrez MA, et al. Enhancement of drug delivery to bone: characterization of human tissue-nonspecific alkaline phosphatase tagged with an acidic oligopeptide. Mol Genet Metab 2006;88(3):244-55.
[Objective]
Maintaining crown-root ratio by cementum and alveolar bone is critical to the success of fixed prosthodontics treatment. Tissue-nonspecific alkaline phosphatase (TNAP), an isoenzyme of alkaline phosphatase (ALP), promotes biological apatite crystallization1). An acidic oligopeptide-tagging approach generated negatively charged TNAP, resulting in more efficient delivery to positively charged mineralized tissue2). Bone sialoprotein knockout (Ibsp-/-) mice exhibit unique phenotype mimicking periodontitis1). This study aimed to determine the effects of TNAP tagged with aspartic acid residues (Asp; Asp-TNAP) on periodontal tissue regeneration.
[Method]
TNAP was generated by removing glycosylphosphatidylinositol-anchoring signal peptide sequence and adding export signal in TNAP sequence. A negatively charged TNAP was provided by adding six Asp codons at C-terminus (Asp6-TNAP). In vitro study was conducted using murine cementoblast-like cell line (OCCM.30) to assess the mineralization effects of Asp6-TNAP with Alizarin Red staining. Ibsp-/- and wild type (WT) mice with mandibular bone defects were locally administered Asp6-TNAP. Histomorphological analyses were performed including micro-computed tomography and histological staining.
[Results and Discussion]
Asp6-TNAP was successfully generated, and ALP enzyme activity was confirmed, suggesting that acidic oligopeptide-tagging approach did not affect enzyme function. Asp6-TNAP promoted mineralization in OCCM.30 cells in WT and Ibsp-/- (4-fold and 11-fold, respectively, compared with control), and these effects were inhibited by TNAP inhibitor. Asp6-TNAP increased alveolar bone volume and mineral density (50 % and 10 %, respectively). Asp6-TNAP significantly induced cementum-like structure formation on the root surface and induced periodontal ligament attachment. These results suggest that Asp6-TNAP substantially promotes periodontal tissue regeneration. Electrically charged TNAP is a promising therapeutic agent that can be applied for adequate tooth abutment and alveolar augmentation for successful prosthodontics treatment.
[References]
1) Nagasaki A, Nagasaki K, Kear BD, et al. Delivery of alkaline phosphatase promotes periodontal regeneration in mice. J Dent Res 2021;100(9):993-1001.
2) Nishioka T, Tomatsu S, Gutierrez MA, et al. Enhancement of drug delivery to bone: characterization of human tissue-nonspecific alkaline phosphatase tagged with an acidic oligopeptide. Mol Genet Metab 2006;88(3):244-55.