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Journal of Clinical Research in... Jun 2024Osteogenesis imperfecta (OI) is a group of phenotypically and genetically heterogeneous connective tissue disorders that share similar skeletal anomalies causing bone...
INTRODUCTION
Osteogenesis imperfecta (OI) is a group of phenotypically and genetically heterogeneous connective tissue disorders that share similar skeletal anomalies causing bone fragility and deformation. This study aimed to investigate the molecular genetic etiology and determine the relationship between genotype and phenotype in OI patients with targeted next-generation sequencing (NGS).
METHOD
In patients with OI, a targeted NGS analysis panel (Illumina TruSight One) containing genes involved in collagen/bone synthesis was performed on the Illumina Nextseq550 platform.
RESULTS
Fifty-six patients (female/male: 25/31) from 46 different families were enrolled in the study. Consanguinity between parents was noted in 15 (32.6%) families. Clinically according to Sillence classification; 18(33.1%) patients were considered to type I, 1(1.7%) type II, 26(46.4%) type III and 11(19.6%) type IV. Median body weight was -1.1 (-6.8, - 2.5) SDS, and height was -2.3 (-7.6, - 1.2) SDS. Bone deformity was detected in 30 (53.5%) of the patients, while 31 (55.4%) were evaluated as mobile. Thirty-six (60.7%) patients had blue sclera, 13 (23.2%) had scoliosis, 12 (21.4%) had dentinogenesis imperfecta (DI), and 2 (3.6%) had hearing loss. Disease-causing variants in COL1A1 and COL1A2 genes were found in 24 (52.1%) and 6 (13%) families, respectively. In 8 (17.3%) of the remaining 16 (34.7%) families, the NGS panel revealed disease-causing variants in three different genes (FKBP10, SERPINF1, and P3H1). Nine (23.6%) of the variants detected in all investigated genes were not previously reported in the literature and were classified to be pathogenic according to ACMG guidelines pathogenity scores. In ten (21.7%) families, a disease-related variant was not found in a total of 13 OI genes included in the panel.
CONCLUSION
Genetic etiology was found in 38 (82.6%) of 46 families by targeted NGS analysis. In addition, 9 new variants were assessed in known OI genes which is a significant contribution to the literature.
PubMed: 38828893
DOI: 10.4274/jcrpe.galenos.2024.2022-12-8 -
Journal of Nanobiotechnology May 2024Pulp regeneration is a novel approach for the treatment of immature permanent teeth with pulp necrosis. This technique includes the combination of stem cells, scaffolds,...
BACKGROUND
Pulp regeneration is a novel approach for the treatment of immature permanent teeth with pulp necrosis. This technique includes the combination of stem cells, scaffolds, and growth factors. Recently, stem cell-derived extracellular vesicles (EVs) have emerged as a new methodology for pulp regeneration. Emerging evidence has proven that preconditioning is an effective scheme to modify EVs for better therapeutic potency. Meanwhile, proper scaffolding is of great significance to protect EVs from rapid clearance and destruction. This investigation aims to fabricate an injectable hydrogel loaded with EVs from pre-differentiated stem cells from human exfoliated deciduous teeth (SHEDs) and examine their effects on pulp regeneration.
RESULTS
We successfully employed the odontogenic induction medium (OM) of SHEDs to generate functional EV (OM-EV). The OM-EV at a concentration of 20 µg/mL was demonstrated to promote the proliferation and migration of dental pulp stem cells (DPSCs). The results revealed that OM-EV has a better potential to promote odontogenic differentiation of DPSCs than common EVs (CM-EV) in vitro through Alizarin red phalloidin, alkaline phosphatase staining, and assessment of the expression of odontogenic-related markers. High-throughput sequencing suggests that the superior effects of OM-EV may be attributed to activation of the AMPK/mTOR pathway. Simultaneously, we prepared a photocrosslinkable gelatin methacryloyl (GelMA) to construct an OM-EV-encapsulated hydrogel. The hydrogel exhibited sustained release of OM-EV and good biocompatibility for DPSCs. The released OM-EV from the hydrogel could be internalized by DPSCs, thereby enhancing their survival and migration. In tooth root slices that were subcutaneously transplanted in nude mice, the OM-EV-encapsulated hydrogel was found to facilitate dentinogenesis. After 8 weeks, there was more formation of mineralized tissue, as well as higher levels of dentin sialophosphoprotein (DSPP) and dentin matrix protein-1 (DMP-1).
CONCLUSIONS
The effects of EV can be substantially enhanced by preconditioning of SHEDs. The functional EVs from SHEDs combined with GelMA are capable of effectively promoting dentinogenesis through upregulating the odontogenic differentiation of DPSCs, which provides a promising therapeutic approach for pulp regeneration.
Topics: Dental Pulp; Humans; Extracellular Vesicles; Gelatin; Cell Differentiation; Odontogenesis; Animals; Stem Cells; Regeneration; Tooth, Deciduous; Methacrylates; Mice; Cell Proliferation; Mice, Nude; Cells, Cultured; Hydrogels; Cell Movement
PubMed: 38760763
DOI: 10.1186/s12951-024-02542-0 -
Journal of Endodontics May 2024Heparan sulfate (HS) is a major component of dental pulp tissue. We previously reported that inhibiting HS biosynthesis impedes endothelial differentiation of dental...
INTRODUCTION
Heparan sulfate (HS) is a major component of dental pulp tissue. We previously reported that inhibiting HS biosynthesis impedes endothelial differentiation of dental pulp stem cells (DPSCs). However, the underlying mechanisms by which exogenous HS induces DPSC differentiation and pulp tissue regeneration remain unknown. This study explores the impact of exogenous HS on vasculogenesis and dentinogenesis of DPSCs both in vitro and in vivo.
METHODS
Human-derived DPSCs were cultured in endothelial and odontogenic differentiation media and treated with HS. Endothelial differentiation of DPSCs was investigated by real-time polymerase chain reaction and capillary sprouting assay. Odontogenic differentiation was assessed through real-time polymerase chain reaction and detection of mineralized dentin-like deposition. Additionally, the influence of HS on pulp tissue was assessed with a direct pulp capping model, in which HS was delivered to exposed pulp tissue in rats. Gelatin sponges were loaded with either phosphate-buffered saline or 10-10 μg/mL HS and placed onto the pulp tissue. Following a 28-day period, tissues were investigated by histological analysis and micro-computed tomography imaging.
RESULTS
HS treatment markedly increased expression levels of key endothelial and odontogenic genes, enhanced the formation of capillary-like structures, and promoted the deposition of mineralized matrices. Treatment of exposed pulp tissue with HS in the in vivo pulp capping study induced formation of capillaries and reparative dentin.
CONCLUSIONS
Exogenous HS effectively promoted vasculogenesis and dentinogenesis of DPSCs in vitro and induced reparative dentin formation in vivo, highlighting its therapeutic potential for pulp capping treatment.
PubMed: 38719089
DOI: 10.1016/j.joen.2024.04.015 -
European Journal of Dentistry May 2024Dental pulp, a specialized mesenchymal tissue within teeth, is pivotal in dental health and tissue repair. Capsaicin, the primary pungent component of chili peppers,...
OBJECTIVES
Dental pulp, a specialized mesenchymal tissue within teeth, is pivotal in dental health and tissue repair. Capsaicin, the primary pungent component of chili peppers, is known for its diverse pharmacological properties. While capsaicin's effects on various cell types have been studied, its impact on dental pulp cells remains relatively unexplored. This study investigated the influence of pure capsaicin extract on dental pulp cell behavior, focusing on cell viability, proliferation, migration, and alkaline phosphatase (ALP) activity.
MATERIALS AND METHODS
Capsaicin solution was prepared and diluted to various concentrations (1 nM, 0.01 µM, 0.1 µM, 1 µM, 10 µM, and 100 µM), then was tested on rat dental pulp cells (RPC-C2A). Cell viability and proliferation were assessed using the MTT assay. Boyden chamber tests and wound healing were used for evaluating cell migration. The activity of ALP was determined to show cell function during dental pulp repair.
STATISTICAL ANALYSIS
The data were analyzed using a one-way analysis of variance or an independent-sample Kruskal-Wallis, followed by multiple comparison tests.
RESULTS
Capsaicin of 100 µM exhibited cytotoxicity, whereas those with lower concentrations stimulated cell proliferation. Wound healing assays revealed increased cell migration, particularly when cultured with 1 nM capsaicin ( = 0.002). Boyden chamber assays demonstrated enhanced cell invasion without statistical significance. ALP activity of dental pulp cells increased significantly at 1 nM ( < 0.001) and 1 µM ( = 0.021) capsaicin concentrations, indicating potential dentinogenesis and pulp repair.
CONCLUSION
Capsaicin of lower concentrations, less than 10 µM, is likely to promote proliferation, migration, and ALP activity of dental pulp cells. Our findings offer potential applications for capsaicin as a medication for dental pulp repair.
PubMed: 38698615
DOI: 10.1055/s-0044-1782191 -
BMC Oral Health Apr 2024Decellularized extracellular matrix (dECM) from several tissue sources has been proposed as a promising alternative to conventional scaffolds used in regenerative...
BACKGROUND
Decellularized extracellular matrix (dECM) from several tissue sources has been proposed as a promising alternative to conventional scaffolds used in regenerative endodontic procedures (REPs). This systematic review aimed to evaluate the histological outcomes of studies utilizing dECM-derived scaffolds for REPs and to analyse the contributing factors that might influence the nature of regenerated tissues.
METHODS
The PRISMA 2020 guidelines were used. A search of articles published until April 2024 was conducted in Google Scholar, Scopus, PubMed and Web of Science databases. Additional records were manually searched in major endodontic journals. Original articles including histological results of dECM in REPs and in-vivo studies were included while reviews, in-vitro studies and clinical trials were excluded. The quality assessment of the included studies was analysed using the ARRIVE guidelines. Risk of Bias assessment was done using the (SYRCLE) risk of bias tool.
RESULTS
Out of the 387 studies obtained, 17 studies were included for analysis. In most studies, when used as scaffolds with or without exogenous cells, dECM showed the potential to enhance angiogenesis, dentinogenesis and to regenerate pulp-like and dentin-like tissues. However, the included studies showed heterogeneity of decellularization methods, animal models, scaffold source, form and delivery, as well as high risk of bias and average quality of evidence.
DISCUSSION
Decellularized ECM-derived scaffolds could offer a potential off-the-shelf scaffold for dentin-pulp regeneration in REPs. However, due to the methodological heterogeneity and the average quality of the studies included in this review, the overall effectiveness of decellularized ECM-derived scaffolds is still unclear. More standardized preclinical research is needed as well as well-constructed clinical trials to prove the efficacy of these scaffolds for clinical translation.
OTHER
The protocol was registered in PROSPERO database #CRD42023433026. This review was funded by the Science, Technology and Innovation Funding Authority (STDF) under grant number (44426).
Topics: Tissue Scaffolds; Regenerative Endodontics; Animals; Extracellular Matrix; Decellularized Extracellular Matrix; Dental Pulp; Models, Animal; Tissue Engineering; Regeneration
PubMed: 38689279
DOI: 10.1186/s12903-024-04266-x -
Clinical Oral Investigations Apr 2024Dentinogenesis imperfecta (DI) is an inherited dentin defect and may be isolated or associated with disorders such as osteogenesis imperfecta, odontochondrodysplasia...
OBJECTIVE
Dentinogenesis imperfecta (DI) is an inherited dentin defect and may be isolated or associated with disorders such as osteogenesis imperfecta, odontochondrodysplasia Ehler-Danlos and others. Isolated DI is caused mainly by pathogenic variants in DSPP gene and around 50 different variants have been described in this gene. Herein, we report on 19 patients from two unrelated Egyptian families with isolated DI. Additionally, we focused on genetic counselling of the two families.
MATERIALS AND METHODS
The patients were examined clinically and dentally. Panoramic X-rays were done to some patients. Whole exome sequencing (WES) and Sanger sequencing were used.
RESULTS
WES revealed two new nonsense variants in DSPP gene, c.288T > A (p.Tyr96Ter) and c.255G > A (p.Trp85Ter). Segregation analysis by Sanger sequencing confirmed the presence of the first variant in all affected members of Family 1 while the second variant was confirmed to be de novo in the patient of Family 2.
CONCLUSIONS AND CLINICAL RELEVANCE
Our study extends the number of DSPP pathogenic variants and strengthens the fact that DSPP is the most common DI causative gene irrespective of patients' ethnicity. In addition, we provide insights on genetic counseling issues in patients with inherited DSPP variants taking into consideration the variable religion, culture and laws in our society.
Topics: Humans; Dentinogenesis Imperfecta; Genetic Counseling; Ethnicity; Osteochondrodysplasias; Radiography, Panoramic
PubMed: 38630328
DOI: 10.1007/s00784-024-05636-z -
Heliyon Apr 2024Bruck syndrome (BS) is an extremely rare autosomal-recessive connective tissue disorder mainly characterized by bone fragility, congenital joint contracture, and spinal...
BACKGROUND
Bruck syndrome (BS) is an extremely rare autosomal-recessive connective tissue disorder mainly characterized by bone fragility, congenital joint contracture, and spinal deformity. It is also considered as a rare form of osteogenesis imperfecta (OI) due to features of osteopenia and fragility fractures. Its two forms, BS1 and BS2, are caused by pathogenic variations in and , respectively.
OBJECTIVE
We aimed to improve the clinical understanding of BS by presenting a case from China and to identify the genetic variants that led to this case.
METHODS
OI was suspected in a Chinese boy with a history of recurrent long bone fractures, lumbar kyphosis, and dentinogenesis imperfecta (DI). Whole-exome sequencing (WES) was performed to identify pathogenic variations. Sanger sequencing was used to confirm the results of the WES. analysis was used to predict the pathogenicity of genetic variants.
RESULTS
WES and Sanger sequencing revealed a compound heterozygous variation in the gene (NM_021939, c.23dupG in exon 1, and c.825dupC in exon 5). Both variants resulted in a frameshift and premature stop codon. Of these two variants, c.23dupG has not been previously reported. The patient's parents were heterozygous carriers of one variant. In addition, zoledronic acid treatment improved the vertebral deformity and bone mineral density (BMD) significantly in this patient.
CONCLUSIONS
A novel compound heterozygous variation of , c.23dupG/c.825dupC, was identified in a patient with moderately severe OI. Based on these findings, the patient was diagnosed with BS1 without congenital joint contractures or OI type XI. This study expands the spectrum of genetic variants that cause BS and OI.
PubMed: 38590901
DOI: 10.1016/j.heliyon.2024.e28680 -
BioRxiv : the Preprint Server For... Mar 2024Regeneration of dentin and odontoblasts from dental pulp stem cells (DPSCs) is essential for permanent tooth maintenance. However, the identity and role of endogenous...
Regeneration of dentin and odontoblasts from dental pulp stem cells (DPSCs) is essential for permanent tooth maintenance. However, the identity and role of endogenous DPSCs in reparative dentinogenesis are elusive. Here, using pulp single-cell analysis before and after molar eruption, we revealed that endogenous DPSCs are enriched in GFP coronal papilla-like cells with Cre labeling. These GFP cells are long-term repopulating cells that contribute to the majority of pulp cells and new odontoblasts after eruption. Upon molar injury, DPSCs localize into the injury site and differentiate into new odontoblasts, forming -GFP and -GFP dentinal tubules and reparative dentin. Single-cell and FACS analysis showed that GFP DPSCs are the most primitive cells with stem cell marker expression and odontoblast differentiation. Taken together, our findings demonstrate that labels postnatal DSPCs, which are the main source of pulp cells and new odontoblasts with reparative dentinogenesis .
PubMed: 38585950
DOI: 10.1101/2024.03.21.586156 -
Journal of the American Dental... May 2024Orthodontic treatment for patients with dentinogenesis imperfecta (DGI) can be risky because of the fragility of their dental hard tissue. Although the Invisalign (Align...
BACKGROUND
Orthodontic treatment for patients with dentinogenesis imperfecta (DGI) can be risky because of the fragility of their dental hard tissue. Although the Invisalign (Align Technology) clear aligner system should be a suitable orthodontic appliance for patients with DGI, to the authors' knowledge, there has been no related research.
CASE DESCRIPTION
A 28-year-old woman with DGI sought treatment with a 1 mm open bite, edge-to-edge occlusion of the central incisors, and a bilateral Class III cusp-to-cusp molar relationship. Invisalign was applied for her treatment, and after 3 and one-half years of orthodontic therapy, a normal overjet and overbite were achieved, accompanied by retraction of the lower lip as well as a bilateral Class I molar relationship. In addition, there was no iatrogenic injury to the patient's teeth.
PRACTICAL IMPLICATIONS
The Invisalign system may be a suitable orthodontic appliance for patients with DGI because clear aligners lessen the tensile stress to the teeth, decrease the number and area of bonds to the teeth, and offer protective effects through a full wrap of plastic that covers the crowns of the teeth.
Topics: Humans; Female; Adult; Dentinogenesis Imperfecta; Orthodontic Appliances, Removable; Tooth Movement Techniques; Orthodontics, Corrective; Orthodontic Appliance Design
PubMed: 38573273
DOI: 10.1016/j.adaj.2024.01.007 -
A homozygous mutation causes osteogenesis and dentinogenesis imperfecta with craniofacial anomalies.JBMR Plus May 2024Osteogenesis imperfecta (OI) is a heterogeneous spectrum of hereditary genetic disorders that cause bone fragility, through various quantitative and qualitative defects...
Osteogenesis imperfecta (OI) is a heterogeneous spectrum of hereditary genetic disorders that cause bone fragility, through various quantitative and qualitative defects of type 1 collagen, a triple helix composed of two α1 and one α2 chains encoded by and , respectively. The main extra-skeletal manifestations of OI include blue sclerae, opalescent teeth, and hearing impairment. Moreover, multiple genes involved in osteoblast maturation and type 1 collagen biosynthesis are now known to cause recessive forms of OI. In this study a multiplex consanguineous family of two affected males with OI was recruited for genetic screening. To determine the causative, pathogenic variant(s), genomic DNA from two affected family members were analyzed using whole exome sequencing, autozygosity mapping, and then validated with Sanger sequencing. The analysis led to the mapping of a homozygous variant previously reported in SP7/OSX, a gene encoding for Osterix, a transcription factor that activates a repertoire of genes involved in osteoblast and osteocyte differentiation and function. The identified variant (c.946C > T; p.Arg316Cys) in exon 2 of results in a pathogenic amino acid change in two affected male siblings and develops OI, dentinogenesis imperfecta, and craniofacial anomaly. On the basis of the findings of the present study, :c. 946C > T is a rare homozygous variant causing OI with extra-skeletal features in inbred Arab populations.
PubMed: 38562913
DOI: 10.1093/jbmrpl/ziae026