Soo-Kyung Jun1, Ji-Young Yoon2, Chinmaya Mahapatra3, Jeong Hui Park4, Hae-Won Kim5, Hyung-Ryong Kim6, Jung-Hwan Lee7, Hae-Hyoung Lee8. 1. Department of Biomaterials Science, School of Dentistry, Dankook University, Cheonan 330-714, South Korea; Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan 330-714, South Korea. Electronic address: iris979@hanmail.net. 2. Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan 330-714, South Korea; Department of Nanobiomedical Science & BK21 PLUS NBM Global Research Center for Regenerative Medicine Research Center, Dankook University, Cheonan 330-714, South Korea. Electronic address: 72160525@dankook.ac.kr. 3. Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan 330-714, South Korea; Department of Nanobiomedical Science & BK21 PLUS NBM Global Research Center for Regenerative Medicine Research Center, Dankook University, Cheonan 330-714, South Korea. Electronic address: cmbbsr@gmail.com. 4. Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan 330-714, South Korea; UCL Eastman-Korea Dental Medicine Innovation Centre, Dankook University, Cheonan 31116, Republic of Korea. 5. Department of Biomaterials Science, School of Dentistry, Dankook University, Cheonan 330-714, South Korea; Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan 330-714, South Korea; Department of Nanobiomedical Science & BK21 PLUS NBM Global Research Center for Regenerative Medicine Research Center, Dankook University, Cheonan 330-714, South Korea; UCL Eastman-Korea Dental Medicine Innovation Centre, Dankook University, Cheonan 31116, Republic of Korea. Electronic address: kimhw@dku.edu. 6. Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan 330-714, South Korea. 7. Department of Biomaterials Science, School of Dentistry, Dankook University, Cheonan 330-714, South Korea; Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan 330-714, South Korea; Department of Nanobiomedical Science & BK21 PLUS NBM Global Research Center for Regenerative Medicine Research Center, Dankook University, Cheonan 330-714, South Korea; UCL Eastman-Korea Dental Medicine Innovation Centre, Dankook University, Cheonan 31116, Republic of Korea. Electronic address: ducious@gmail.com. 8. Department of Biomaterials Science, School of Dentistry, Dankook University, Cheonan 330-714, South Korea; Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan 330-714, South Korea; UCL Eastman-Korea Dental Medicine Innovation Centre, Dankook University, Cheonan 31116, Republic of Korea. Electronic address: haelee@dankook.ac.kr.
Abstract
OBJECTIVE: Odontoblast differentiation from dental pulp stem cells (DPSCs) is involved in a cascade of key biological events for maintaining pulp-dentin homeostasis, repair and regeneration. A pulp regeneration biomaterial (mineral trioxide aggregate (MTA)) increased intracellular reactive oxygen species (ROS) levels during differentiation, ameliorating the differentiating of DPSCs into odontoblasts. Here, ceria nanoparticles (CNP) were incorporated as an insoluble antioxidant into commercially available MTA (CMTA), and the odontoblastic differentiation of human DPSCs was investigated. METHODS: The CMTA was fabricated from MTA and CNP conjugation up to 4wt%, and the compressive strength, surface morphology after setting and setting time were investigated. Furthermore, the alkaline phosphatase (ALP) assay, Alizarin Red staining (ARS) and quantitative real-time polymerase chain reaction (qPCR) were performed to evaluate odontoblastic differentiation in an indirect co-culture system using inserts with pores. To reveal the underlying mechanism, the ROS levels and ion release were measured. Statistical analysis was performed by one-way analysis of variance with a Tukey post hoc test (P<0.05). RESULTS: CMTA significantly elevated the odontoblastic differentiation of hDPSCs measured by ALP activity, ARS, and odontoblastic gene expression, whereas the other physico-mechanical properties were relatively maintained. Upregulation of gene expression from CMTA was reversed with hydrogen peroxide. CMTA could reduce the increased intracellular ROS levels of hDPSCs by approximately 70% during differentiation, similar to when an antioxidant was used, without changing the ion release and pH of the media. SIGNIFICANCE: CMTA could be useful dental materials for regenerating dentin-pulp complexes by instructing intracellular ROS during differentiation to achieve beneficial biological functions. This study suggests a new direction of dental nanomaterials in treating pulp-dentin complexes.
OBJECTIVE: Odontoblast differentiation from dental pulp stem cells (DPSCs) is involved in a cascade of key biological events for maintaining pulp-dentin homeostasis, repair and regeneration. A pulp regeneration biomaterial (mineral trioxide aggregate (MTA)) increased intracellular reactive oxygen species (ROS) levels during differentiation, ameliorating the differentiating of DPSCs into odontoblasts. Here, ceria nanoparticles (CNP) were incorporated as an insoluble antioxidant into commercially available MTA (CMTA), and the odontoblastic differentiation of human DPSCs was investigated. METHODS: The CMTA was fabricated from MTA and CNP conjugation up to 4wt%, and the compressive strength, surface morphology after setting and setting time were investigated. Furthermore, the alkaline phosphatase (ALP) assay, Alizarin Red staining (ARS) and quantitative real-time polymerase chain reaction (qPCR) were performed to evaluate odontoblastic differentiation in an indirect co-culture system using inserts with pores. To reveal the underlying mechanism, the ROS levels and ion release were measured. Statistical analysis was performed by one-way analysis of variance with a Tukey post hoc test (P<0.05). RESULTS:CMTA significantly elevated the odontoblastic differentiation of hDPSCs measured by ALP activity, ARS, and odontoblastic gene expression, whereas the other physico-mechanical properties were relatively maintained. Upregulation of gene expression from CMTA was reversed with hydrogen peroxide. CMTA could reduce the increased intracellular ROS levels of hDPSCs by approximately 70% during differentiation, similar to when an antioxidant was used, without changing the ion release and pH of the media. SIGNIFICANCE: CMTA could be useful dental materials for regenerating dentin-pulp complexes by instructing intracellular ROS during differentiation to achieve beneficial biological functions. This study suggests a new direction of dental nanomaterials in treating pulp-dentin complexes.