Apigenin, a natural product belonging to the flavone class, affects various cell physiologies, such as cell signaling, inflammation, proliferation, migration, and protease production. In this study, ...apigenin was applied to mouse molar pulp after mechanically pulpal exposure to examine the detailed function of apigenin in regulating pulpal inflammation and tertiary dentin formation.
cell cultivation using human dental pulp stem cells (hDPSCs) and
mice model experiments were employed to examine the effect of apigenin in the pulp and dentin regeneration.
cultivation of hDPSCs with apigenin treatment upregulated bone morphogenetic protein (BMP)- and osteogenesis-related signaling molecules such as BMP2, BMP4, BMP7, bone sialoprotein (BSP), runt-related transcription factor 2 (RUNX2), and osteocalcin (OCN) after 14 days. After apigenin local delivery in the mice pulpal cavity, histology and cellular physiology, such as the modulation of inflammation and differentiation, were examined using histology and immunostainings. Apigenin-treated specimens showed period-altered immunolocalization patterns of tumor necrosis factor (TNF)-α, myeloperoxidase (MPO), NESTIN, and transforming growth factor (TGF)-β1 at 3 and 5 days. Moreover, the apigenin-treated group showed a facilitated dentin-bridge formation with few irregular tubules after 42 days from pulpal cavity preparation. Micro-CT images confirmed obvious dentin-bridge structures in the apigenin-treated specimens compared with the control. Apigenin facilitated the reparative dentin formation through the modulation of inflammation and the activation of signaling regulations. Therefore, apigenin would be a potential therapeutic agent for regenerating dentin in exposed pulp caused by dental caries and traumatic injury.
For hard tissue formation, cellular mechanisms, involved in protein folding, processing, and secretion play important roles in the endoplasmic reticulum (ER). In pathological and regeneration ...conditions, ER stress hinders proper formation and secretion of proteins, and tissue regeneration by unfolded protein synthesis. 4-Phenylbutyric acid (4PBA) is a chemical chaperone that alleviates ER stress through modulation in proteins folding and protein trafficking. However, previous studies about 4PBA only focused on the metabolic diseases rather than on hard tissue formation and regeneration. Herein, we evaluated the function of 4PBA in dentin regeneration using an exposed pulp animal model system via a local delivery method as a drug repositioning strategy. Our results showed altered morphological changes and cellular physiology with histology and immunohistochemistry. The 4PBA treatment modulated the inflammation reaction and resolved ER stress in the early stage of pulp exposure. In addition, 4PBA treatment activated blood vessel formation and TGF-β1 expression in the dentin-pulp complex. Micro-computed tomography and histological examinations confirmed the facilitated formation of the dentin bridge in the 4PBA-treated specimens. These results suggest that proper modulation of ER stress would be an important factor for secretion and patterned formation in dentin regeneration.
FUSE binding protein 1 (
), a regulator of the c-Myc transcription factor and a DNA/RNA-binding protein, plays important roles in the regulation of gene transcription and cellular physiology. In this ...study, to reveal the precise developmental function of
, we examined the detailed expression pattern and developmental function of
during tooth morphogenesis by RT-qPCR, in situ hybridization, and knock-down study using in vitro organ cultivation methods. In embryogenesis,
is obviously expressed in the enamel organ and condensed mesenchyme, known to be important for proper tooth formation. Knocking down
at E14 for two days, showed the altered expression patterns of tooth development related signalling molecules, including
and
. In addition, transient knock-down of
at E14 revealed changes in the localization patterns of c-Myc and cell proliferation in epithelium and mesenchyme, related with altered tooth morphogenesis. These results also showed the decreased amelogenin and dentin sialophosphoprotein expressions and disrupted enamel rod and interrod formation in one- and three-week renal transplanted teeth respectively. Thus, our results suggested that
plays a modulating role during dentinogenesis and amelogenesis by regulating the expression pattern of signalling molecules to achieve the proper structural formation of hard tissue matrices and crown morphogenesis in mice molar development.
Prohibitin (PHB) is an essential scaffold protein that modulates signaling pathways controlling cell survival, metabolism, inflammation, and bone formation. However, its specific role in periodontium ...development remains less understood. This study aims to elucidate the expression pattern and function of PHB in periodontium development and its involvement in alveolar bone formation.
Immunolocalization of PHB in the periodontium of postnatal (PN) mice were examined.
morpholino was micro-injected into the right-side mandible at PN5, corresponding to the position where the alveolar bone process forms in relation to the lower first molar. The micro-injection with a scramble control (PF-127) and the left-side mandibles were used as control groups. Five days post-micro-injection, immunohistochemical analysis and micro-CT evaluation were conducted to assess bone mass and morphological changes. Additionally, expression patterns of signaling molecules were examined following
downregulation using 24-h
cultivation of developing dental mesenchyme at E14.5.
The immunostaining of PHB showed its localization in the periodontium at PN5, PN8, and PN10. The
cultivation of dental mesenchyme resulted in alterations in Bmps, Runx2, and Wnt signalings after
knock-down. At 5 days post-micro-injection,
knocking down showed weak immunolocalizations of runt-related transcription factor (RUNX2) and osteocalcin (OCN). However, knocking down
led to histological alterations characterized by decreased bone mass and stronger localizations of Ki67 and PERIOSTIN in the periodontium compared 1 to control groups. The micro-CT evaluation showed decreased bone volume and increased PDL space in the
knock-down specimens, suggesting its regulatory role in bone formation.
The region-specific localization of PHB in the margin where alveolar bone forms suggests its involvement in alveolar bone formation and the differentiation of the periodontal ligament. Overall, our findings suggest that
plays a modulatory role in alveolar bone formation by harmoniously regulating bone-forming-related signaling molecules during periodontium development.
A 16-year-old male presented with pain in the right posterior mandible on chewing that had lasted for several months. The radiographic features of the lesion included a radiolucent-radiopaque ...mixed-density mass with a radiolucent rim attached to the root of the mandibular right first molar. The preliminary radiographic diagnosis was benign cementoblastoma, which was confirmed by histopathological examination following surgical excision. The lesion recurred 3 years after treatment; radiographically, it consisted of 3 round foci with mixed radiopacity, each with a radiolucent rim near the root of the mandibular right second premolar and the edentulous postoperative region. The lesion was diagnosed as recurrent benign cementoblastoma and a second surgery was scheduled. This report presented an unusual case of recurrent benign cementoblastoma following surgical excision and extraction of the involved tooth, along with a literature review on reported cases of recurrent benign cementoblastoma with a focus on its clinical features and the best treatment options.
This report presents the case of a 49-year-old man who presented with giant masses that had recently grown on the bilateral sides of the tongue. A clinical examination revealed rubbery yellowish ...lesions protruding from the tongue. A panoramic radiograph showed an enlarged soft tissue shadow of the tongue. Computed tomography showed well-defined circumscribed mass exhibiting a homogeneous low density on the bilateral sides of the tongue. On magnetic resonance images, the masses showed a high signal intensity on T1-weighted images and iso-signal intensity with partially hyperintense margin on fat-suppressed T2-weighted images. Surgical excision was performed, and a histopathologic examination confirmed the diagnosis of lipoma. The patient recovered well with no sign of recurrence. A giant lipoma is defined as a lipoma larger than 5 cm in diameter. A literature review of giant lipomas of the tongue is also presented herein.
Background
The tongue is a muscular fleshy organ in the oral cavity that is anatomically divided into the dorsal, ventral, anterior, and posterior part. The intricate tissue organisation and diverse ...origins of the tongue make it a complex organ of the oral cavity.
Objectives
To reveal the signalling molecules involved in the formation of the dorsal and ventral parts of the tongue through microarray analysis.
Methods
Dorsal and ventral tongue tissues were isolated from embryonic day 14 mice by micro-dissection. RNA was extracted from the dorsal and ventral tongue tissues separately for microarray analysis. Microarray data were confirmed by quantitative reverse transcription polymerase chain reaction and whole-mount in situ hybridisation.
Results
Microarray analysis revealed expression of 33,793 genes. Of these, 931 genes were found to be equally expressed in both the dorsal and ventral parts of the tongue. On limiting the fold-change cut-off to over 1.5-fold, 725 genes were expressed over 1.5-fold in the ventral part and 1,672 in the dorsal part of the tongue. The qPCR and whole-mount in situ hybridisation revealed the expressions of angiopoietin 2 (
Angpt2
), fibroblast growth factor 18 (
Fgf18
), mesenchyme homeobox gene1 (
Meox1
), and SPARC-related modular calcium binding 2 (
Smoc2
) in the ventral part of the tongue.
Conclusions
Numerous signalling molecules can be selected from our microarray results to examine their roles in tongue development and disease model systems. In the near future, the selection of candidate genes and their functional evaluations will be performed through loss- and gain-of-function mutation studies.
A 10-year-old boy presented with a swelling on the right side of the jaw. He had undergone excision of the lesion about 10 months ago at a private dental clinic and the swelling began to regrow ...4 months after surgery. A panoramic radiograph revealed 4 sclerotic round masses with radiolucent rims surrounded by sclerosis of the right posterior mandible. Computed tomography scan showed 4 round bony masses centered on the buccal cortex and bone marrow space, sclerosis of the adjacent bone and periosteal reaction. He underwent a marginal resection under general anesthesia and the final histopathological report confirmed the diagnosis of osteoid osteoma. Postoperative course was uneventful, and there was no evidence of recurrence at the 5.5-year follow-up. In the review of the literature, 20 osteoid ostemas were found in the jaw and to the best of our knowledge, the present case is the only one showing multifocal nidi.
Objectives This study aimed to assess the hard and soft tissue changes in osteomyelitis (OM) of the jaws using CT images. Study Design The CT images of 153 patients (59 males and 94 females) with OM ...of the jaws were retrospectively reviewed. The relationships between each space involvement, between space and muscle involvements, between cortical bone defect and space involvement, and between cortical bone defect and muscle involvement were evaluated. Results The cortical bone defect was more common on the buccal side in the maxilla and on the lingual side in the mandible. The most commonly involved muscle was the buccinator muscle in the maxilla and the masseter muscle in the mandible and the most frequently involved space was the buccal space followed by the masticator space. Conclusions CT is a useful tool in evaluating both hard and soft tissue changes of OM of the jaws.
Objectives This study contributes three well-documented cases of multiple simple bone cysts (SBCs) of the jaws and reviews previously published cases. Study Design A comprehensive literature search ...of multiple SBCs was conducted using the PubMed database. Synonyms of SBC were used as search key words in combination with “mandible or jaw,” “bilateral, multiple, multifocal, atypical, and unusual.” Results A total of 34 cases of multiple SBCs (including two asynchronous cases) were identified, including the three new cases reported here. Multiple SBCs primarily occurred in the second decade (52.9%) and bilaterally in the posterior mandible. Lesions demonstrated female predominance (1.8:1) and were frequently accompanied by bony expansion (44.1%) and a multilocular radiolucent appearance (20.6 %). Recurrence was reported in three patients (mean age: 39.3 years old). Conclusion Knowledge of the clinical and radiographic features of multiple SBCs is important in the diagnosis and management of this entity.
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