Eosinophilic granulomatous with polyangiitis complicated by swelling of the oral cavity floor and cervical soft tissue as initial manifestation mimicking IgG4-related disease: A case report.

Eosinophilic granulomatous polyangiitis is a systemic vasculitis associated with bronchial asthma and eosinophilic sinusitis. Here, we describe an unusual presentation of eosinophilic granulomatous polyangiitis that initially manifested as swelling of the oral cavity floor and cervical soft tissue. A 58 year-old Japanese man was diagnosed with bronchial asthma during childhood but did not receive regular medication. Prior to this presentation, he had a persistent cough for over 1 month, and a local physician diagnosed him with bronchial asthma. However, 6 months later, his cough worsened, and a blood test revealed elevated eosinophil levels. Immediately afterward, swelling of the floor of the oral cavity and cervical soft tissue developed. Cellulitis was suspected and antimicrobial treatment was initiated; however, the symptoms persisted and abdominal pain developed. An endoscopic examination revealed duodenitis and a duodenal ulcer. The patient was diagnosed with eosinophilic granulomatous polyangiitis based on three items of the 2022 American College of Rheumatology/European College of Rheumatology classification criteria: obstructive airway disease, blood eosinophil count ≥1 × 109 cells/L, and extravascular eosinophilic infiltration with a score of 10. Oral prednisolone (70 mg/day), intravenous cyclophosphamide (500 mg/m2), and subcutaneous mepolizumab (300 mg every 4 weeks) were administered. The patient's symptoms improved after these treatments, and the eosinophil count and inflammatory marker levels declined. When swelling of the oral cavity floor and cervical soft tissue following an increase in eosinophilia and allergic symptoms occurs, it is crucial to consider the likelihood of eosinophilic granulomatous polyangiitis and collaborate with otolaryngologists and dentists to ensure its prompt identification.

Decrease in Glycosaminoglycan with Aging in Normal Rat Articular Cartilage Is Greater in Females than in Males.

OBJECTIVE: Osteoarthritis (OA) is more prevalent in females. We hypothesized that changes in articular cartilage (AC) constituents with aging may cause differences. Herein, we aimed to compare the changes in AC constituents with aging in male and female normal rats. DESIGN: The glycosaminoglycan (GAG) and collagen (COL) contents of the AC in knee, hip, and shoulder joints of male and female rats were quantified and compared between age groups and sexes. RESULTS: The amount of GAG was decreased in multiple joints in both males and females with aging. In females, it had a significant decrease in all joints measured. The decrease in GAG with aging was more severe in females than in males. Even in young rats, the amount of knee joint GAG was significantly less in females than in males. The amount of COL in the AC was unchanged with aging in both sexes. CONCLUSIONS: The drastic GAG decrease with aging in female normal rats may explain the higher prevalence and more severe OA in females.

Ten-m/Odz3 regulates migration and differentiation of chondrogenic ATDC5 cells via RhoA-mediated actin reorganization.

Tenascin-like molecule major (Ten-m)/odd Oz (Odz), a type II transmembrane molecule, is well known to modulate neural development. We have reported that Ten-m/Odz3 is expressed in cartilaginous tissues and cells. Actin cytoskeleton and its regulator ras homolog gene family member A (RhoA) are closely associated with chondrogenesis. The present study aimed to evaluate the function and molecular mechanism of Ten-m/Odz3 during chondrogenesis, focusing on RhoA and the actin cytoskeleton. Ten-m/Odz3 was expressed in precartilaginous condensing mesenchyme in mouse limb buds. Ten-m/Odz3 knockdown in ATDC5 induced actin cytoskeleton reorganization and change of cell shape through modulation of RhoA activity and FGF2 expression. Ten-m/Odz3 knockdown suppressed ATDC5 migration and expression of genes associated with chondrogenesis, such as Sox9 and type II collagen, via RhoA. On the other hand, Ten-m/Odz3 knockdown inhibited proliferation of ATDC5 in a RhoA-independent manner. These findings suggest that Ten-m/Odz3 plays an important role in early chondrogenesis regulating RhoA-mediated actin reorganization.

Methionine Enkephalin Suppresses Osteocyte Apoptosis Induced by Compressive Force through Regulation of Nuclear Translocation of NFATc1.

Mechanical stress stimulates bone remodeling, which occurs through bone formation and resorption, resulting in bone adaptation in response to the mechanical stress. Osteocytes perceive mechanical stress loaded to bones and promote bone remodeling through various cellular processes. Osteocyte apoptosis is considered a cellular process to induce bone resorption during mechanical stress-induced bone remodeling, but the underlying molecular mechanisms are not fully understood. Recent studies have demonstrated that neuropeptides play crucial roles in bone metabolism. The neuropeptide, methionine enkephalin (MENK) regulates apoptosis positively and negatively depending on cell type, but the role of MENK in osteocyte apoptosis, followed by bone resorption, in response to mechanical stress is still unknown. Here, we examined the roles and mechanisms of MENK in osteocyte apoptosis induced by compressive force. We loaded compressive force to mouse parietal bones, resulting in a reduction of MENK expression in osteocytes. A neutralizing connective tissue growth factor (CTGF) antibody inhibited the compressive force-induced reduction of MENK. An increase in osteocyte apoptosis in the compressive force-loaded parietal bones was inhibited by MENK administration. Nuclear translocation of NFATc1 in osteocytes in the parietal bones was enhanced by compressive force. INCA-6, which inhibits NFAT translocation into nuclei, suppressed the increase in osteocyte apoptosis in the compressive force-loaded parietal bones. NFATc1-overexpressing MLO-Y4 cells showed increased expression of apoptosis-related genes. MENK administration reduced the nuclear translocation of NFATc1 in osteocytes in the compressive force-loaded parietal bones. Moreover, MENK suppressed Ca2+ influx and calcineurin and calmodulin expression, which are known to induce the nuclear translocation of NFAT in MLO-Y4 cells. In summary, this study shows that osteocytes expressed MENK, whereas the MENK expression was suppressed by compressive force via CTGF signaling. MENK downregulated nuclear translocation of NFATc1 probably by suppressing Ca2+ signaling in osteocytes and consequently inhibiting compressive force-induced osteocyte apoptosis, followed by bone resorption. © 2020 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

Insulin-like growth factor 1 modulates bioengineered tooth morphogenesis.

Regenerative therapy to replace missing teeth is a critical area of research. Functional bioengineered teeth have been produced by the organ germ method using mouse tooth germ cells. However, these bioengineered teeth are significantly smaller in size and exhibit an abnormal crown shape when compared with natural teeth. The proper sizes and shapes of teeth contribute to their normal function. Therefore, a method is needed to control the morphology of bioengineered teeth. Here, we investigated whether insulin-like growth factor 1 (IGF1) can regulate the sizes and shapes of bioengineered teeth, and assessed underlying mechanisms of such regulation. IGF1 treatment significantly increased the size of bioengineered tooth germs, while preserving normal tooth histology. IGF1-treated bioengineered teeth, which were developed from bioengineered tooth germs in subrenal capsules and jawbones, showed increased sizes and cusp numbers. IGF1 increased the number of fibroblast growth factor (Fgf4)-expressing enamel knots in bioengineered tooth germs and enhanced the proliferation and differentiation of dental epithelial and mesenchymal cells. This study is the first to reveal that IGF1 increases the sizes and cusp numbers of bioengineered teeth via the induction of enamel knot formation, as well as the proliferation and differentiation of dental epithelial and mesenchymal cells.

In vivo expression and regulation of genes associated with vascularization during early response of sutures to tensile force.

Sutures are fibrous tissues that connect bones in craniofacial skeletal complexes. Cranio- and dentofacial skeletal deformities in infant and adolescent patients can be treated by applying tensile force to sutures to induce sutural bone formation. The early gene expression induced by mechanical stress is essential for bone formation in long bones; however, early gene expression during sutural bone formation induced by tensile force is poorly characterized. In vivo studies are essential to evaluate molecular responses to mechanical stresses in heterogeneous cell populations, such as sutures. In this paper we examined in vivo early gene expression and the underlying regulatory mechanism for this expression in tensile-force-applied cranial sutures, focusing on genes involved in vascularization. Tensile force upregulated expression of vascular factors, such as vascular endothelial growth factor (Vegf) and endothelial cell markers, in sutures within 3 h. The expression of connective tissue growth factor (Ctgf) and Rho-associated coiled-coil containing protein kinase 2 (Rock2) was also upregulated by tensile force. A CTGF-neutralizing antibody and the ROCK inhibitor, Y-27632, abolished tensile-force-induced Vegf expression. Moreover, tensile force activated extracellular signal-related kinase 1/2 (ERK1/2) signaling in sagittal sutures, and the ERK1/2 inhibitor, U0126, partially inhibited tensile-force-induced Ctgf expression. These results indicate that tensile force induces in vivo gene expression associated with vascularization early in tensile-force-induced sutural bone formation. Moreover, the early induction of Vegf gene expression is regulated by CTGF and ROCK2.

Differentiation of Odontoblast-Like Cells From Mouse Induced Pluripotent Stem Cells by Pax9 and Bmp4 Transfection.

UNLABELLED: The field of tooth regeneration has progressed in recent years, and human tooth regeneration could become viable in the future. Because induced pluripotent stem (iPS) cells can differentiate into odontogenic cells given appropriate conditions, iPS cells are a potential cell source for tooth regeneration. However, a definitive method to induce iPS cell-derived odontogenic cells has not been established. We describe a novel method of odontoblast differentiation from iPS cells using gene transfection. We generated mouse iPS cell-derived neural crest-like cells (iNCLCs), which exhibited neural crest markers. Next, we differentiated iNCLCs into odontoblast-like cells by transfection of Pax9 and Bmp4 expression plasmids. Exogenous Pax9 upregulated expression of Msx1 and dentin matrix protein 1 (Dmp1) in iNCLCs but not bone morphogenetic protein 4 (Bmp4) or dentin sialophosphoprotein (Dspp). Exogenous Bmp4 upregulated expression of Msx1, Dmp1, and Dspp in iNCLCs, but not Pax9. Moreover, cotransfection of Pax9 and Bmp4 plasmids in iNCLCs revealed a higher expression of Pax9 than when Pax9 plasmid was used alone. In contrast, exogenous Pax9 downregulated Bmp4 overexpression. Cotransfection of Pax9 and Bmp4 synergistically upregulated Dmp1 expression; however, Pax9 overexpression downregulated exogenous Bmp4-induced Dspp expression. Together, these findings suggest that an interaction between exogenous Pax9- and Bmp4-induced signaling modulated Dmp1 and Dspp expression. In conclusion, transfection of Pax9 and Bmp4 expression plasmids in iNCLCs induced gene expression associated with odontoblast differentiation, suggesting that iNCLCs differentiated into odontoblast-like cells. The iPS cell-derived odontoblast-like cells could be a useful cell source for tooth regeneration. SIGNIFICANCE: It has been reported that induced pluripotent stem (iPS) cells differentiate into odontogenic cells by administration of recombinant growth factors and coculture with odontogenic cells. Therefore, they can be potential cell sources for tooth regeneration. However, these previous methods still have problems, such as usage of other cell types, heterogeneity of differentiated cells, and tumorigenicity. In the present study, a novel method to differentiate iPS cells into odontoblast-like cells without tumorigenicity using gene transfection was established. It is an important advance in the establishment of efficient methods to generate homogeneous functional odontogenic cells derived from iPS cells.