The oral inflammatory diseases are divided into two types: acute and chronic inflammatory disease... more The oral inflammatory diseases are divided into two types: acute and chronic inflammatory diseases. In this review, we summarize the biological efficacy of herbal medicine, natural products, and their active ingredients against acute and chronic inflammatory diseases in the oral region, especially stomatitis and periodontitis. We review the effects of herbal medicines and a biscoclaurin alkaloid preparation, cepharamthin, as a therapy against stomatitis, an acute inflammatory disease. We also summarize the effects of herbal medicines and natural products against periodontitis, a chronic inflammatory disease, and one of its clinical conditions, alveolar bone resorption. Recent studies show that several herbal medicines such as kakkonto and ninjinto reduce LPS-induced PGE 2 production by human gingival fibroblasts. Among herbs constituting these herbal medicines, shokyo (Zingiberis Rhizoma) and kankyo (Zingiberis Processum Rhizoma) strongly reduce PGE 2 production. Moreover, anti-osteoclast activity has been observed in some natural products with anti-inflammatory effects used against rheumatoid arthritis such as carotenoids, flavonoids, limonoids, and polyphenols. These herbal medicines and natural products could be useful for treating oral inflammatory diseases.
Bone tissues have trabecular bone with a high bone turnover and cortical bone with a low turnover... more Bone tissues have trabecular bone with a high bone turnover and cortical bone with a low turnover. The mechanisms by which the turnover rate of these bone tissues is determined remain unclear. Osteocytes secrete sclerostin, a Wnt/β-catenin signaling antagonist, and inhibit bone formation. We found that sclerostin expression in cortical bone is more marked than in trabecular bone inSostreporter mice. Leukemia inhibitory factor (LIF) secreted from osteoclasts reportedly suppressed sclerostin expression and promoted bone formation. Here, we report that osteoclasts downregulate sclerostin expression in trabecular bone and promote bone turnover. Treatment of C57BL/6 mice with an anti-RANKL antibody eliminated the number of osteoclasts and LIF-positive cells in trabecular bone. The number of sclerostin-positive cells was increased in trabecular bone, while the number of β-catenin-positive cells and bone formation were decreased in trabecular bone. Besides,Tnfsf11heterozygous (Rankl+/−) mi...
Previously, we revealed that several kampo medicines which are used for the patients with excess ... more Previously, we revealed that several kampo medicines which are used for the patients with excess and/or medium patterns [kakkonto (TJ-1), shosaikoto (TJ-9), hangeshashinto (TJ-14), and orento (TJ-120)] decreased prostaglandin (PG)E2 by LPS-treated human gingival fibroblasts (HGFs). Currently, we examined other kampo medicines which are used for the patients with deficiency pattern [bakumondoto (TJ-29), shinbuto (TJ-30), ninjinto (TJ-32), and hochuekkito (TJ-41)] and the herbs which construct shinbuto and ninjinto using the same experimental model. Shinbuto and ninjinto concentration-dependently decreased LPS-induced PGE2 production by HGFs, whereas hochuekkito weakly decreased and bakumondoto did not decrease PGE2 production. Shinbuto and ninjinto did not alter cyclooxygenase (COX) activities and the expressions of molecules involved in arachidonic acid cascade. Next, we examined which herbs constructing shinbuto and ninjinto decrease LPS-induced PGE2 production. Among these herbs, ...
We previously reported that shokyo and kankyo, which are water-extracted fractions of ginger, red... more We previously reported that shokyo and kankyo, which are water-extracted fractions of ginger, reduced LPS-induced PGE2 production in human gingival fibroblasts. In this study, we examined the effects of these herbs on LPS-treated mouse macrophage RAW264.7 cells. Both shokyo and kankyo reduced LPS-induced PGE2 production in a concentration-dependent manner. Shokyo and kankyo did not inhibit cyclooxygenase (COX) activity, nor did they alter the expression of molecules in the arachidonic acid cascade. In addition, these herbs did not alter NF-κB p65 translocation into nucleus, or phosphorylation of p65 or ERK. These results suggest that shokyo and kankyo inhibit cPLA2 activity. Although 6-shogaol produced similar results to those of shokyo and kankyo, the concentration of 6-shogaol required for the reduction of PGE2 production were higher than those of 6-shogaol in shokyo and kankyo. Therefore, several gingerols and shogaols other than 6-shogaol may play a role in the reduction of LPS-...
The chemotactic factors directing interneuron migration during cerebrocortical development are es... more The chemotactic factors directing interneuron migration during cerebrocortical development are essentially unknown. Here we identify the CXC chemokine receptor 4 (CXCR4) in interneuron precursors migrating from the basal forebrain to the neocortex and demonstrate that stromal cell-derived factor-1 (SDF-1) is a potent chemoattractant for isolated striatal precursors. In addition, we show that CXCR4 is present in early generated Cajal-Retzius cells of the cortical marginal zone. In mice with a null mutation in CXCR4 or SDF-1, interneurons were severely underrepresented in the superficial layers and ectopically placed in the deep layers of the neocortex. In contrast, the submeningeal positioning of Cajal-Retzius cells was unaffected. Thus, our findings suggest that SDF-1, which is highly expressed in the embryonic leptomeninx, selectively regulates migration and layer-specific integration of CXCR4-expressing interneurons during neocortical development.
The oral inflammatory diseases are divided into two types: acute and chronic inflammatory disease... more The oral inflammatory diseases are divided into two types: acute and chronic inflammatory diseases. In this review, we summarize the biological efficacy of herbal medicine, natural products, and their active ingredients against acute and chronic inflammatory diseases in the oral region, especially stomatitis and periodontitis. We review the effects of herbal medicines and a biscoclaurin alkaloid preparation, cepharamthin, as a therapy against stomatitis, an acute inflammatory disease. We also summarize the effects of herbal medicines and natural products against periodontitis, a chronic inflammatory disease, and one of its clinical conditions, alveolar bone resorption. Recent studies show that several herbal medicines such as kakkonto and ninjinto reduce LPS-induced PGE 2 production by human gingival fibroblasts. Among herbs constituting these herbal medicines, shokyo (Zingiberis Rhizoma) and kankyo (Zingiberis Processum Rhizoma) strongly reduce PGE 2 production. Moreover, anti-oste...
Objective: A RANKL-binding peptide, WP9QY (W9), is known to inhibit mouse osteoclastogenesis by s... more Objective: A RANKL-binding peptide, WP9QY (W9), is known to inhibit mouse osteoclastogenesis by stimulating the production of autocrine factors such as bone morphogenetic proteins (BMPs) to induce osteoblast differentiation. In the present study, we investigated whether osteoblastic differentiation is mediated by RANKL signaling. Methods: The effect of W9 on the differentiation of osteoclasts and osteoblasts was examined in mouse bone-marrow cultures, and in a mouse co-culture system consisting of primary osteoblasts derived from RANKL-deficient or wild-type (WT) newborn mouse calvariae, with WT-derived bone marrow mononuclear cells. Results: The addition of the W9 peptide to the WT mouse bone-marrow culture simultaneously inhibited RANKL-induced tartrate-resistant acid phosphatase (TRAP)-positive osteoclast differentiation, and stimulated alkaline phosphatase (ALP)-positive osteoblastic calcified nodule formation. RANKL-deficient osteoblasts exhibited weak ALP activity compared to WT osteoblasts. W9 treatment strongly inhibited TRAP-positive osteoclast formation, and stimulated ALP-positive osteoblast differentiation in co-cultures of WT-derived osteoblasts and bone-marrow cells, in the presence of bone-resorbing factors. In contrast, W9 exerted only a weak effect on ALP-positive osteoblast differentiation in co-cultures with RANKLdeficient osteoblasts, even in the presence of the W9 peptide, parathyroid hormone, and/or BMP-2. Conclusions: The W9 peptide inhibited RANKL-mediated osteoclast formation in osteoblasts. It also directly stimulated osteoblast differentiation, both via RANKL signaling-mediated autocrine factors, and alternative mechanisms.
We previously demonstrated that a kampo medicine, kakkonto, decreases lipopolysaccharide- (LPS-) ... more We previously demonstrated that a kampo medicine, kakkonto, decreases lipopolysaccharide- (LPS-) induced prostaglandin E2(PGE2) production by human gingival fibroblasts. In this study, we examined the herbs constituting kakkonto that exhibit this effect. Shokyo strongly and concentration dependently and kanzo and keihi moderately decreased LPS-induced PGE2production. Shokyo did not alter cyclooxygenase-2 (COX-2) activity, cytosolic phospholipase A2(cPLA2), annexin 1 and COX-2 expression, and LPS-induced extracellular signal-regulated kinase (ERK) phosphorylation. Kanzo inhibited COX-2 activity but increased annexin 1 and COX-2 expression and did not alter LPS-induced ERK phosphorylation. Keihi inhibited COX-2 activity and LPS-induced ERK phosphorylation but slightly increased COX-2 expression and did not alter cPLA2and annexin 1 expression. These results suggest that the mechanism of shokyo is through the inhibition of cPLA2activity, and that of kanzo and keihi is through the inhibi...
Metal-binding proteins, metallothioneins (MTs), may play important roles in bone metabolism. Howe... more Metal-binding proteins, metallothioneins (MTs), may play important roles in bone metabolism. However, the contribution of MTs to bone metabolism remains obscure. In the present study, we investigated the expression of MT isoforms in bone cells and mRNA for MT isoforms in the tibiae following ovariectomy (OVX). The results obtained showed that MT-I/II and MT-III were expressed in osteoblasts, osteoclasts, and osteocytes 4 weeks after OVX. Peaks in the mRNA expression ratios (OVX/Sham) of MT-I/II and MT-III changed following OVX. The expression ratio of MT-I/II increased after 1 week, whereas that of MT-III increased 4 weeks after OVX. These results suggest that the contribution of MTs to bone metabolism may depend on the isoforms in the cell types and the stage after OVX.
To study the relationship between the biological and morphological characteristics of oral intrae... more To study the relationship between the biological and morphological characteristics of oral intraepithelial neoplasms (OINs), we examined the localization of desmosome-related proteins. Twentyseven cases of OIN3 were tentatively classified as basaloid (14 cases) or differentiated (13 cases), and the latter were further subdivided into verrucous (five cases) and acanthotic (eight cases) subtypes. All samples were stained using antibodies against desmoglein 1 (DSG1), desmocollin 3 (DSC3), junction plakoglobin (JUP) and serine peptidase inhibitor Kazal type 5 (SPINK5) domain. All variants of OIN3 showed significantly high rates of positivity for DSG1 in the basal layer (basaloid 57%; differentiated 85%), DSC3 in the surface layer (basaloid 93%; differentiated 77%) and JUP in the basal and parabasal layers (basaloid 93%; differentiated 62%). Interestingly, even the basaloid type showed areas of alternating DSG1 positivity and negativity, reflecting keratinocyte maturation. Therefore, most cases of OIN appear to have the characteristics of well differentiated squamous epithelium.
Periodontal disease is accompanied by inflammation of the gingiva and destruction of periodontal ... more Periodontal disease is accompanied by inflammation of the gingiva and destruction of periodontal tissues, leading to alveolar bone loss in severe clinical cases. The chemical mediator prostaglandin E2 (PGE2) and cytokines such as interleukin- (IL-)6 and IL-8 have been known to play important roles in inflammatory responses and tissue degradation. In the present study, we investigated the effects of a kampo medicine, kakkonto (TJ-1), on the production of prostaglandin E2 (PGE2), IL-6, and IL-8 by human gingival fibroblasts (HGFs) treated with lipopolysaccharide (LPS) from Porphyromonas gingivalis. Kakkonto concentration dependently suppressed LPS-induced PGE2 production but did not alter basal PGE2 levels. In contrast, kakkonto significantly increased LPS-induced IL-6 and IL-8 production. Kakkonto decreased cyclooxygenase- (COX-)1 activity to approximately 70% at 1 mg/mL but did not affect COX-2 activity. Kakkonto did not affect cytoplasmic phospholipase A2 (cPLA2), annexin1, or LPS-...
Some kinds of drugs such as calcium (Ca(2+)) channel antagonists, antiepileptics and immunosuppre... more Some kinds of drugs such as calcium (Ca(2+)) channel antagonists, antiepileptics and immunosuppressants cause gingival overgrowth as a side effect, the mechanism of which is still unclear. We have examined the effects of isradipine, one of the dihydropyridine-derivative Ca(2+) channel antagonists, on cultured human gingival fibroblast Gin-1 cells. In the present study, to elucidate the mechanism by which isradipine causes gingival overgrowth, we examined whether tyrosine kinase (TK) and phopholipase Cgamma (PLCgamma) are involved in the isradipine-induced proliferation of gingival fibroblasts. Herbimycin A (1 microM) remarkably inhibited the isradipime (10 microM)-induced proliferation. Both U73122 (5 microM), a PLCgamma inhibitor, and xestospongin C (5 microM), an antagonist of a receptor of inositol 1,4,5-trisphosphate in Ca(2+) stores, significantly reduced the [Ca(2+)]i raised by isradipine (10 microM). Thus, the findings obtained here indicate that TK and PLCgamma are closely i...
Abstract Kampo medicines are clinically used for the treatment of various diseases, and their use... more Abstract Kampo medicines are clinically used for the treatment of various diseases, and their use for oral diseases is desired; however, only a few kampo medicines are adaptable for diseases of the oral region. Against this background, we carried out an investigation into the application of preexisting kampo medicines to diseases of the oral region. Here, we indicate the effects of kampo medicines on periodontal disease, drug-induced gingival overgrowth, and xerostomia using in vitro or animal models. (i) Shosaikoto has an anti-inflammatory effect and is used for the treatment of pneumonia and bronchitis. Because shosaikoto decreases lipopolysaccharide (LPS)-induced prostaglandin E 2 production by gingival fibroblasts, it may be effective to improve inflammation in periodontal tissue. (ii) Saireito has an inhibitory effect on cell proliferation and is used for the treatment of idiopathic retroperitoneal fibrosis. Because saireito suppresses nifedipine-induced gingival fibroblast proliferation, it may be effective for the treatment of drug-induced gingival overgrowth. (iii) Byakkokaninjinto and goreisan are used for the treatment of xerostomia. Because diabetes is accompanied by xerostomia, the effects of these two medicines on salivary secretion have been examined using streptozotocin-induced diabetic mice. Both medicines recover the blood glucose level and secretory rate of saliva to almost normal levels. These results suggest that kampo medicines may be adaptable for periodontal disease, drug-induced gingival overgrowth, and diabetes-mediated xerostomia.
The aim of this study was to examine whether human gingival fibroblasts (HGFs) sustain to produce... more The aim of this study was to examine whether human gingival fibroblasts (HGFs) sustain to produce prostaglandin E 2 (PGE 2) in the presence of lipopolysaccharide (LPS). HGFs were treated with or without 10 ng/ml of LPS from Porphyromonas gingivalis (PgLPS) for 7 days collecting the culture supernatants for every 24 h, and PGE 2 concentration in the supernatants was measured by ELISA. HGFs produced PGE 2 at low level without PgLPS treatment. In contrast, HGFs continuously produce PGE 2 with PgLPS treatment. At each day, the amount of PGE 2 production by HGFs with PgLPS treatment was higher than that without treatment. These results demonstrate that the characteristic of HGFs, which continuously produce PGE 2 in the presence of LPS, sustains inflammatory response in periodontal disease.
Proceedings of the National Academy of Sciences, 2003
Primordial germ cells (PGCs) are the founders of sperm or oocytes. PGCs migrate through the tissu... more Primordial germ cells (PGCs) are the founders of sperm or oocytes. PGCs migrate through the tissues of the embryos and colonize the gonads during development. However, the cytokines essential for colonization of the gonads by PGCs in mammals remain unclear. Stromal cell-derived factor-1 (SDF-1, also called PBSF and CXCL12) is a member of chemokines, a family of structurally related chemoattractive cytokines. SDF-1 and its primary physiologic receptor CXCR4 have multiple essential functions in development including colonization of bone marrow by hematopoietic cells and neuron localization within cerebellum during embryogenesis as well as B lymphopoiesis and cardiovasculogenesis. Here, we have shown that PGCs have cell-surface expression of CXCR4 and that, in SDF-1 −/− mice, PGCs undergo directed migration through tissues of embryos, but the numbers of PGCs in the gonads are significantly reduced. The proliferation of PGCs within the gonads seems normal in the mutant mice. These findi...
Background and Objective: A major factor in the pathogenesis of periodontal disease, which is on... more Background and Objective: A major factor in the pathogenesis of periodontal disease, which is one of the biofilm infectious diseases, is thought to be lipopolysaccharide (LPS), owing to its ability to cause inflammation and promote tissue destruction. Moreover, the elimination of pathogens and their component LPSs is essential for the successful treatment of periodontal disease. Lipopolysaccharide tolerance is a mechanism that prevents excessive and prolonged responses of monocytes and macrophages to LPS. Since persistence of inflammation is necessary for inflammatory cytokine production, cells other than monocytes and macrophages are thought to maintain the production of cytokines in the presence of LPS. In this study, we investigated whether human gingival fibroblasts (HGFs), the most abundant structural cell in periodontal tissue, might be able to maintain inflammatory cytokine production in the presence of LPS by not displaying LPS tolerance.Material and Methods: Human gingiva...
Objective: Periodontal disease is accompanied by inflammation of the gingiva and destruction of p... more Objective: Periodontal disease is accompanied by inflammation of the gingiva and destruction of periodontal tissues, leading to alveolar bone loss in severe clinical cases. Interleukin (IL)-6, IL-8, and the chemical mediator prostaglandin E 2 (PGE 2) are known to play important roles in inflammatory responses and tissue degradation. Recently, we reported that the protein kinase A (PKA) inhibitor H-89 suppresses lipopolysaccharide (LPS)-induced IL-8 production by human gingival fibroblasts (HGFs). In the present study, the relevance of the PKA activity and two PKA-activating drugs, aminophylline and adrenaline, to LPS-induced inflammatory cytokines (IL-6 and IL-8) and PGE 2 by HGFs were examined. Methods: HGFs were treated with LPS from Porphyromonas gingivalis and H-89, the cAMP analog dibutyryl cyclic AMP (dbcAMP), aminophylline, or adrenaline. After 24 h, IL-6, IL-8, and PGE 2 levels were evaluated by ELISA. Results: H-89 did not affect LPS-induced IL-6 production, but suppressed IL-8 and PGE 2 production. In contrast, dbcAMP significantly increased LPS-induced IL-6, IL-8, and PGE 2 production. Up to 10 μg/ml of aminophylline did not affect LPS-induced IL-6, IL-8, or PGE 2 production, but they were significantly increased at 100 μg/ml. Similarly, 0.01 μg/ml of adrenaline did not affect LPS-induced IL-6, IL-8, or PGE 2 production, but they were significantly increased at concentrations of 0.1 and 1 μg/ml. In the absence of LPS, H-89, dbcAMP, aminophylline, and adrenaline had no relevance to IL-6, IL-8, or PGE 2 production. Conclusion: These results suggest that the PKA pathway, and also PKA-activating drugs, enhance LPS-induced IL-6, IL-8, and PGE 2 production by HGFs. However, aminophylline may not have an effect on the production of these molecules at concentrations used in clinical settings (8 to 20 μg/ml in serum). These results suggest that aminophylline does not affect inflammatory responses in periodontal disease.
The functions of a chemokine CXC chemokine ligand (CXCL) 12/stromal cell-derived factor-1/pre-B c... more The functions of a chemokine CXC chemokine ligand (CXCL) 12/stromal cell-derived factor-1/pre-B cell growth stimulating factor and its physiologic receptor CXCR4 in T cell development are controversial. In this study, we have genetically further characterized their roles in fetal and adult T cell development using mutant and chimeric mice. In CXCL12−/− or CXCR4−/− embryos on a C57BL/6 background, accumulation of T cell progenitors in the outer mesenchymal layer of the thymus anlage during initial colonization of the fetal thymus was comparable with that seen in wild-type embryos. However, the expansion of CD3−CD4−CD8− triple-negative T cell precursors at the CD44−CD25+ and CD44−CD25− stages, and CD4+CD8+ double-positive thymocytes was affected during embryogenesis in these mutants. In radiation chimeras competitively repopulated with CXCR4−/− fetal liver cells, the reduction in donor-derived thymocytes compared with wild-type chimeras was much more severe than the reduction in donor...
The oral inflammatory diseases are divided into two types: acute and chronic inflammatory disease... more The oral inflammatory diseases are divided into two types: acute and chronic inflammatory diseases. In this review, we summarize the biological efficacy of herbal medicine, natural products, and their active ingredients against acute and chronic inflammatory diseases in the oral region, especially stomatitis and periodontitis. We review the effects of herbal medicines and a biscoclaurin alkaloid preparation, cepharamthin, as a therapy against stomatitis, an acute inflammatory disease. We also summarize the effects of herbal medicines and natural products against periodontitis, a chronic inflammatory disease, and one of its clinical conditions, alveolar bone resorption. Recent studies show that several herbal medicines such as kakkonto and ninjinto reduce LPS-induced PGE 2 production by human gingival fibroblasts. Among herbs constituting these herbal medicines, shokyo (Zingiberis Rhizoma) and kankyo (Zingiberis Processum Rhizoma) strongly reduce PGE 2 production. Moreover, anti-osteoclast activity has been observed in some natural products with anti-inflammatory effects used against rheumatoid arthritis such as carotenoids, flavonoids, limonoids, and polyphenols. These herbal medicines and natural products could be useful for treating oral inflammatory diseases.
Bone tissues have trabecular bone with a high bone turnover and cortical bone with a low turnover... more Bone tissues have trabecular bone with a high bone turnover and cortical bone with a low turnover. The mechanisms by which the turnover rate of these bone tissues is determined remain unclear. Osteocytes secrete sclerostin, a Wnt/β-catenin signaling antagonist, and inhibit bone formation. We found that sclerostin expression in cortical bone is more marked than in trabecular bone inSostreporter mice. Leukemia inhibitory factor (LIF) secreted from osteoclasts reportedly suppressed sclerostin expression and promoted bone formation. Here, we report that osteoclasts downregulate sclerostin expression in trabecular bone and promote bone turnover. Treatment of C57BL/6 mice with an anti-RANKL antibody eliminated the number of osteoclasts and LIF-positive cells in trabecular bone. The number of sclerostin-positive cells was increased in trabecular bone, while the number of β-catenin-positive cells and bone formation were decreased in trabecular bone. Besides,Tnfsf11heterozygous (Rankl+/−) mi...
Previously, we revealed that several kampo medicines which are used for the patients with excess ... more Previously, we revealed that several kampo medicines which are used for the patients with excess and/or medium patterns [kakkonto (TJ-1), shosaikoto (TJ-9), hangeshashinto (TJ-14), and orento (TJ-120)] decreased prostaglandin (PG)E2 by LPS-treated human gingival fibroblasts (HGFs). Currently, we examined other kampo medicines which are used for the patients with deficiency pattern [bakumondoto (TJ-29), shinbuto (TJ-30), ninjinto (TJ-32), and hochuekkito (TJ-41)] and the herbs which construct shinbuto and ninjinto using the same experimental model. Shinbuto and ninjinto concentration-dependently decreased LPS-induced PGE2 production by HGFs, whereas hochuekkito weakly decreased and bakumondoto did not decrease PGE2 production. Shinbuto and ninjinto did not alter cyclooxygenase (COX) activities and the expressions of molecules involved in arachidonic acid cascade. Next, we examined which herbs constructing shinbuto and ninjinto decrease LPS-induced PGE2 production. Among these herbs, ...
We previously reported that shokyo and kankyo, which are water-extracted fractions of ginger, red... more We previously reported that shokyo and kankyo, which are water-extracted fractions of ginger, reduced LPS-induced PGE2 production in human gingival fibroblasts. In this study, we examined the effects of these herbs on LPS-treated mouse macrophage RAW264.7 cells. Both shokyo and kankyo reduced LPS-induced PGE2 production in a concentration-dependent manner. Shokyo and kankyo did not inhibit cyclooxygenase (COX) activity, nor did they alter the expression of molecules in the arachidonic acid cascade. In addition, these herbs did not alter NF-κB p65 translocation into nucleus, or phosphorylation of p65 or ERK. These results suggest that shokyo and kankyo inhibit cPLA2 activity. Although 6-shogaol produced similar results to those of shokyo and kankyo, the concentration of 6-shogaol required for the reduction of PGE2 production were higher than those of 6-shogaol in shokyo and kankyo. Therefore, several gingerols and shogaols other than 6-shogaol may play a role in the reduction of LPS-...
The chemotactic factors directing interneuron migration during cerebrocortical development are es... more The chemotactic factors directing interneuron migration during cerebrocortical development are essentially unknown. Here we identify the CXC chemokine receptor 4 (CXCR4) in interneuron precursors migrating from the basal forebrain to the neocortex and demonstrate that stromal cell-derived factor-1 (SDF-1) is a potent chemoattractant for isolated striatal precursors. In addition, we show that CXCR4 is present in early generated Cajal-Retzius cells of the cortical marginal zone. In mice with a null mutation in CXCR4 or SDF-1, interneurons were severely underrepresented in the superficial layers and ectopically placed in the deep layers of the neocortex. In contrast, the submeningeal positioning of Cajal-Retzius cells was unaffected. Thus, our findings suggest that SDF-1, which is highly expressed in the embryonic leptomeninx, selectively regulates migration and layer-specific integration of CXCR4-expressing interneurons during neocortical development.
The oral inflammatory diseases are divided into two types: acute and chronic inflammatory disease... more The oral inflammatory diseases are divided into two types: acute and chronic inflammatory diseases. In this review, we summarize the biological efficacy of herbal medicine, natural products, and their active ingredients against acute and chronic inflammatory diseases in the oral region, especially stomatitis and periodontitis. We review the effects of herbal medicines and a biscoclaurin alkaloid preparation, cepharamthin, as a therapy against stomatitis, an acute inflammatory disease. We also summarize the effects of herbal medicines and natural products against periodontitis, a chronic inflammatory disease, and one of its clinical conditions, alveolar bone resorption. Recent studies show that several herbal medicines such as kakkonto and ninjinto reduce LPS-induced PGE 2 production by human gingival fibroblasts. Among herbs constituting these herbal medicines, shokyo (Zingiberis Rhizoma) and kankyo (Zingiberis Processum Rhizoma) strongly reduce PGE 2 production. Moreover, anti-oste...
Objective: A RANKL-binding peptide, WP9QY (W9), is known to inhibit mouse osteoclastogenesis by s... more Objective: A RANKL-binding peptide, WP9QY (W9), is known to inhibit mouse osteoclastogenesis by stimulating the production of autocrine factors such as bone morphogenetic proteins (BMPs) to induce osteoblast differentiation. In the present study, we investigated whether osteoblastic differentiation is mediated by RANKL signaling. Methods: The effect of W9 on the differentiation of osteoclasts and osteoblasts was examined in mouse bone-marrow cultures, and in a mouse co-culture system consisting of primary osteoblasts derived from RANKL-deficient or wild-type (WT) newborn mouse calvariae, with WT-derived bone marrow mononuclear cells. Results: The addition of the W9 peptide to the WT mouse bone-marrow culture simultaneously inhibited RANKL-induced tartrate-resistant acid phosphatase (TRAP)-positive osteoclast differentiation, and stimulated alkaline phosphatase (ALP)-positive osteoblastic calcified nodule formation. RANKL-deficient osteoblasts exhibited weak ALP activity compared to WT osteoblasts. W9 treatment strongly inhibited TRAP-positive osteoclast formation, and stimulated ALP-positive osteoblast differentiation in co-cultures of WT-derived osteoblasts and bone-marrow cells, in the presence of bone-resorbing factors. In contrast, W9 exerted only a weak effect on ALP-positive osteoblast differentiation in co-cultures with RANKLdeficient osteoblasts, even in the presence of the W9 peptide, parathyroid hormone, and/or BMP-2. Conclusions: The W9 peptide inhibited RANKL-mediated osteoclast formation in osteoblasts. It also directly stimulated osteoblast differentiation, both via RANKL signaling-mediated autocrine factors, and alternative mechanisms.
We previously demonstrated that a kampo medicine, kakkonto, decreases lipopolysaccharide- (LPS-) ... more We previously demonstrated that a kampo medicine, kakkonto, decreases lipopolysaccharide- (LPS-) induced prostaglandin E2(PGE2) production by human gingival fibroblasts. In this study, we examined the herbs constituting kakkonto that exhibit this effect. Shokyo strongly and concentration dependently and kanzo and keihi moderately decreased LPS-induced PGE2production. Shokyo did not alter cyclooxygenase-2 (COX-2) activity, cytosolic phospholipase A2(cPLA2), annexin 1 and COX-2 expression, and LPS-induced extracellular signal-regulated kinase (ERK) phosphorylation. Kanzo inhibited COX-2 activity but increased annexin 1 and COX-2 expression and did not alter LPS-induced ERK phosphorylation. Keihi inhibited COX-2 activity and LPS-induced ERK phosphorylation but slightly increased COX-2 expression and did not alter cPLA2and annexin 1 expression. These results suggest that the mechanism of shokyo is through the inhibition of cPLA2activity, and that of kanzo and keihi is through the inhibi...
Metal-binding proteins, metallothioneins (MTs), may play important roles in bone metabolism. Howe... more Metal-binding proteins, metallothioneins (MTs), may play important roles in bone metabolism. However, the contribution of MTs to bone metabolism remains obscure. In the present study, we investigated the expression of MT isoforms in bone cells and mRNA for MT isoforms in the tibiae following ovariectomy (OVX). The results obtained showed that MT-I/II and MT-III were expressed in osteoblasts, osteoclasts, and osteocytes 4 weeks after OVX. Peaks in the mRNA expression ratios (OVX/Sham) of MT-I/II and MT-III changed following OVX. The expression ratio of MT-I/II increased after 1 week, whereas that of MT-III increased 4 weeks after OVX. These results suggest that the contribution of MTs to bone metabolism may depend on the isoforms in the cell types and the stage after OVX.
To study the relationship between the biological and morphological characteristics of oral intrae... more To study the relationship between the biological and morphological characteristics of oral intraepithelial neoplasms (OINs), we examined the localization of desmosome-related proteins. Twentyseven cases of OIN3 were tentatively classified as basaloid (14 cases) or differentiated (13 cases), and the latter were further subdivided into verrucous (five cases) and acanthotic (eight cases) subtypes. All samples were stained using antibodies against desmoglein 1 (DSG1), desmocollin 3 (DSC3), junction plakoglobin (JUP) and serine peptidase inhibitor Kazal type 5 (SPINK5) domain. All variants of OIN3 showed significantly high rates of positivity for DSG1 in the basal layer (basaloid 57%; differentiated 85%), DSC3 in the surface layer (basaloid 93%; differentiated 77%) and JUP in the basal and parabasal layers (basaloid 93%; differentiated 62%). Interestingly, even the basaloid type showed areas of alternating DSG1 positivity and negativity, reflecting keratinocyte maturation. Therefore, most cases of OIN appear to have the characteristics of well differentiated squamous epithelium.
Periodontal disease is accompanied by inflammation of the gingiva and destruction of periodontal ... more Periodontal disease is accompanied by inflammation of the gingiva and destruction of periodontal tissues, leading to alveolar bone loss in severe clinical cases. The chemical mediator prostaglandin E2 (PGE2) and cytokines such as interleukin- (IL-)6 and IL-8 have been known to play important roles in inflammatory responses and tissue degradation. In the present study, we investigated the effects of a kampo medicine, kakkonto (TJ-1), on the production of prostaglandin E2 (PGE2), IL-6, and IL-8 by human gingival fibroblasts (HGFs) treated with lipopolysaccharide (LPS) from Porphyromonas gingivalis. Kakkonto concentration dependently suppressed LPS-induced PGE2 production but did not alter basal PGE2 levels. In contrast, kakkonto significantly increased LPS-induced IL-6 and IL-8 production. Kakkonto decreased cyclooxygenase- (COX-)1 activity to approximately 70% at 1 mg/mL but did not affect COX-2 activity. Kakkonto did not affect cytoplasmic phospholipase A2 (cPLA2), annexin1, or LPS-...
Some kinds of drugs such as calcium (Ca(2+)) channel antagonists, antiepileptics and immunosuppre... more Some kinds of drugs such as calcium (Ca(2+)) channel antagonists, antiepileptics and immunosuppressants cause gingival overgrowth as a side effect, the mechanism of which is still unclear. We have examined the effects of isradipine, one of the dihydropyridine-derivative Ca(2+) channel antagonists, on cultured human gingival fibroblast Gin-1 cells. In the present study, to elucidate the mechanism by which isradipine causes gingival overgrowth, we examined whether tyrosine kinase (TK) and phopholipase Cgamma (PLCgamma) are involved in the isradipine-induced proliferation of gingival fibroblasts. Herbimycin A (1 microM) remarkably inhibited the isradipime (10 microM)-induced proliferation. Both U73122 (5 microM), a PLCgamma inhibitor, and xestospongin C (5 microM), an antagonist of a receptor of inositol 1,4,5-trisphosphate in Ca(2+) stores, significantly reduced the [Ca(2+)]i raised by isradipine (10 microM). Thus, the findings obtained here indicate that TK and PLCgamma are closely i...
Abstract Kampo medicines are clinically used for the treatment of various diseases, and their use... more Abstract Kampo medicines are clinically used for the treatment of various diseases, and their use for oral diseases is desired; however, only a few kampo medicines are adaptable for diseases of the oral region. Against this background, we carried out an investigation into the application of preexisting kampo medicines to diseases of the oral region. Here, we indicate the effects of kampo medicines on periodontal disease, drug-induced gingival overgrowth, and xerostomia using in vitro or animal models. (i) Shosaikoto has an anti-inflammatory effect and is used for the treatment of pneumonia and bronchitis. Because shosaikoto decreases lipopolysaccharide (LPS)-induced prostaglandin E 2 production by gingival fibroblasts, it may be effective to improve inflammation in periodontal tissue. (ii) Saireito has an inhibitory effect on cell proliferation and is used for the treatment of idiopathic retroperitoneal fibrosis. Because saireito suppresses nifedipine-induced gingival fibroblast proliferation, it may be effective for the treatment of drug-induced gingival overgrowth. (iii) Byakkokaninjinto and goreisan are used for the treatment of xerostomia. Because diabetes is accompanied by xerostomia, the effects of these two medicines on salivary secretion have been examined using streptozotocin-induced diabetic mice. Both medicines recover the blood glucose level and secretory rate of saliva to almost normal levels. These results suggest that kampo medicines may be adaptable for periodontal disease, drug-induced gingival overgrowth, and diabetes-mediated xerostomia.
The aim of this study was to examine whether human gingival fibroblasts (HGFs) sustain to produce... more The aim of this study was to examine whether human gingival fibroblasts (HGFs) sustain to produce prostaglandin E 2 (PGE 2) in the presence of lipopolysaccharide (LPS). HGFs were treated with or without 10 ng/ml of LPS from Porphyromonas gingivalis (PgLPS) for 7 days collecting the culture supernatants for every 24 h, and PGE 2 concentration in the supernatants was measured by ELISA. HGFs produced PGE 2 at low level without PgLPS treatment. In contrast, HGFs continuously produce PGE 2 with PgLPS treatment. At each day, the amount of PGE 2 production by HGFs with PgLPS treatment was higher than that without treatment. These results demonstrate that the characteristic of HGFs, which continuously produce PGE 2 in the presence of LPS, sustains inflammatory response in periodontal disease.
Proceedings of the National Academy of Sciences, 2003
Primordial germ cells (PGCs) are the founders of sperm or oocytes. PGCs migrate through the tissu... more Primordial germ cells (PGCs) are the founders of sperm or oocytes. PGCs migrate through the tissues of the embryos and colonize the gonads during development. However, the cytokines essential for colonization of the gonads by PGCs in mammals remain unclear. Stromal cell-derived factor-1 (SDF-1, also called PBSF and CXCL12) is a member of chemokines, a family of structurally related chemoattractive cytokines. SDF-1 and its primary physiologic receptor CXCR4 have multiple essential functions in development including colonization of bone marrow by hematopoietic cells and neuron localization within cerebellum during embryogenesis as well as B lymphopoiesis and cardiovasculogenesis. Here, we have shown that PGCs have cell-surface expression of CXCR4 and that, in SDF-1 −/− mice, PGCs undergo directed migration through tissues of embryos, but the numbers of PGCs in the gonads are significantly reduced. The proliferation of PGCs within the gonads seems normal in the mutant mice. These findi...
Background and Objective: A major factor in the pathogenesis of periodontal disease, which is on... more Background and Objective: A major factor in the pathogenesis of periodontal disease, which is one of the biofilm infectious diseases, is thought to be lipopolysaccharide (LPS), owing to its ability to cause inflammation and promote tissue destruction. Moreover, the elimination of pathogens and their component LPSs is essential for the successful treatment of periodontal disease. Lipopolysaccharide tolerance is a mechanism that prevents excessive and prolonged responses of monocytes and macrophages to LPS. Since persistence of inflammation is necessary for inflammatory cytokine production, cells other than monocytes and macrophages are thought to maintain the production of cytokines in the presence of LPS. In this study, we investigated whether human gingival fibroblasts (HGFs), the most abundant structural cell in periodontal tissue, might be able to maintain inflammatory cytokine production in the presence of LPS by not displaying LPS tolerance.Material and Methods: Human gingiva...
Objective: Periodontal disease is accompanied by inflammation of the gingiva and destruction of p... more Objective: Periodontal disease is accompanied by inflammation of the gingiva and destruction of periodontal tissues, leading to alveolar bone loss in severe clinical cases. Interleukin (IL)-6, IL-8, and the chemical mediator prostaglandin E 2 (PGE 2) are known to play important roles in inflammatory responses and tissue degradation. Recently, we reported that the protein kinase A (PKA) inhibitor H-89 suppresses lipopolysaccharide (LPS)-induced IL-8 production by human gingival fibroblasts (HGFs). In the present study, the relevance of the PKA activity and two PKA-activating drugs, aminophylline and adrenaline, to LPS-induced inflammatory cytokines (IL-6 and IL-8) and PGE 2 by HGFs were examined. Methods: HGFs were treated with LPS from Porphyromonas gingivalis and H-89, the cAMP analog dibutyryl cyclic AMP (dbcAMP), aminophylline, or adrenaline. After 24 h, IL-6, IL-8, and PGE 2 levels were evaluated by ELISA. Results: H-89 did not affect LPS-induced IL-6 production, but suppressed IL-8 and PGE 2 production. In contrast, dbcAMP significantly increased LPS-induced IL-6, IL-8, and PGE 2 production. Up to 10 μg/ml of aminophylline did not affect LPS-induced IL-6, IL-8, or PGE 2 production, but they were significantly increased at 100 μg/ml. Similarly, 0.01 μg/ml of adrenaline did not affect LPS-induced IL-6, IL-8, or PGE 2 production, but they were significantly increased at concentrations of 0.1 and 1 μg/ml. In the absence of LPS, H-89, dbcAMP, aminophylline, and adrenaline had no relevance to IL-6, IL-8, or PGE 2 production. Conclusion: These results suggest that the PKA pathway, and also PKA-activating drugs, enhance LPS-induced IL-6, IL-8, and PGE 2 production by HGFs. However, aminophylline may not have an effect on the production of these molecules at concentrations used in clinical settings (8 to 20 μg/ml in serum). These results suggest that aminophylline does not affect inflammatory responses in periodontal disease.
The functions of a chemokine CXC chemokine ligand (CXCL) 12/stromal cell-derived factor-1/pre-B c... more The functions of a chemokine CXC chemokine ligand (CXCL) 12/stromal cell-derived factor-1/pre-B cell growth stimulating factor and its physiologic receptor CXCR4 in T cell development are controversial. In this study, we have genetically further characterized their roles in fetal and adult T cell development using mutant and chimeric mice. In CXCL12−/− or CXCR4−/− embryos on a C57BL/6 background, accumulation of T cell progenitors in the outer mesenchymal layer of the thymus anlage during initial colonization of the fetal thymus was comparable with that seen in wild-type embryos. However, the expansion of CD3−CD4−CD8− triple-negative T cell precursors at the CD44−CD25+ and CD44−CD25− stages, and CD4+CD8+ double-positive thymocytes was affected during embryogenesis in these mutants. In radiation chimeras competitively repopulated with CXCR4−/− fetal liver cells, the reduction in donor-derived thymocytes compared with wild-type chimeras was much more severe than the reduction in donor...
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Papers by Toshiaki Ara