Injury of the periodontium followed by inflammatory response often leads to mot resorption. Resorption is accomplished by osteoclasts and their generation may depend on an interaction with the cells in direct contact ...Injury of the periodontium followed by inflammatory response often leads to mot resorption. Resorption is accomplished by osteoclasts and their generation may depend on an interaction with the cells in direct contact with the root, the cementoblasts. Our study aimed to investigate the role of human cementoblasts in the formation of osteoclasts and the effect of interleukin （IL）- 1β hereupon. Extracted teeth from healthy volunteers were subjected to sequential digestion by type I collagenase and trypsin. The effect of enzymatic digestion on the presence of cells on the root surface was analyzed by histology. Gene expression of primary human cementoblasts （pHCB） was compared with a human cementoblast cell line （HCEM）. The pHCBs were analyzed for their expression of IL-1 receptors as well as of receptor activator of nuclear factor kappa-B ligand （RANKL） and osteoprotegerin （OPG）. In a co-culture system consisting of osteoclast precursors （blood monocytes） and pHCBs, the formation of osteoclasts and their resorptive activity was assessed by osteo-assay and ivory slices. The cells obtained after a 120 min enzyme digestion expressed the highest level of bone sialoprotein, similar to that of HCEM. This fraction of isolated cells also shared a similar expression pattern of IL-1 receptors （ILl-R1 and ILl-R2）. Treatment with IL-11~ potently upregulated RANKL expression but not of OPG. pHCBs were shown to induce the formation of functional osteoclasts. This capacity was significantly stimulated by pretreating the pHCBs with IL-1β prior to their co-culture with human blood monocytes. Our study demonstrated that cementoblasts have the capacity to induce osteoclastogenesis, a capacity strongly promoted by IL-1β. These results may explain why osteoclasts can be formed next to the root of teeth.展开更多
AIM:To investigate hepcidin expression,interleukin-6(IL-6)production and iron levels in the rat colon in the presence of trinitrobenzene sulfonic acid(TNBS)-induced colitis.METHODS:In rats,we evaluated the severity of...AIM:To investigate hepcidin expression,interleukin-6(IL-6)production and iron levels in the rat colon in the presence of trinitrobenzene sulfonic acid(TNBS)-induced colitis.METHODS:In rats,we evaluated the severity of colitis induced by repeated TNBS administration using macroscopic and microscopic scoring systems and myeloperoxidase activity measurements.The colonic levels of hepcidin,tumor necrosis factor alpha(TNF-α),IL-10 and IL-6 were measured by Enzyme-Linked Immunosorbent Assay,and hepcidin-25 expression and iron deposition were analyzed by immunohistochemistry and the Prussian blue reaction,respectively.Stat-3 phosphorylation was assessed by Western blot analysis.Hematological parameters,iron and transferrin levels,and transferrin saturation were also measured.Additionally,the ability of iron,pathogen-derived molecules and IL-6 to induce hepcidin expression in HT-29 cells was evaluated.RESULTS:Repeated TNBS administration to rats resulted in macroscopically and microscopically detectable colon lesions and elevated colonic myeloperoxidase activity.Hepcidin-25 protein levels were increased in colonic surface epithelia in colitic rats(10.2±4.0pg/mg protein vs 71.0±8.4 pg/mg protein,P<0.01).Elevated IL-6 levels(8.2±1.7 pg/mg protein vs 14.7±0.7 pg/mg protein,P<0.05),TNF-αlevels(1.8±1.2pg/mg protein vs 7.4±2.1 pg/mg protein,P<0.05)and Stat-3 phosphorylation were also observed.Systemic alterations in iron homeostasis,hepcidin levels and anemia were not detected in colitic rats.Iron deposition in the colon was only observed during colitis.Hepcidin gene expression was increased in HT-29 cells after IL-6 and lipopolysaccharide[a toll-like receptor 4(TLR-4)ligand]treatment.Deferoxamine,ferric citrate and peptidoglycan(a TLR-2 ligand)were unable to alter the in vitro expression of hepcidin in HT-29 cells.CONCLUSION:Colitis increased local hepcidin-25 expression,which was associated with the IL-6/Stat-3 signaling pathway.An increase in local iron sequestration was also observed,but additional studies are need展开更多
Background Recent studies have shown that interleukin-3 receptor α （CD123） is highly expressed on leukemia stem cells of patients with acute myeloid leukemia, and is correlated with tumor load and poor prognosis.Th...Background Recent studies have shown that interleukin-3 receptor α （CD123） is highly expressed on leukemia stem cells of patients with acute myeloid leukemia, and is correlated with tumor load and poor prognosis.The expression of CD123 may also be high in patients with myelodysplastic syndrome （MDS）.In this study, the expression and clinical significance of CD123 and granulocyte colony stimulating factor （G-CSF） receptor （CD114） on the bone marrow cells of patients with MDS were investigated to explore the molecular marker of the malignant clone of MDS.Methods Forty-two patients with MDS, who were diagnosed in the Hematological Department of General Hospital of Tianjin Medical University from 2008 to 2009, and twelve normal controls were enrolled in this study.Fluorescence activiated cell sorter （FACS） was used to measure the expression of CD123 on CD34＋CD38- cells and CD114 on CD34＋cells of the bone marrow of these patients and controls and the clinical significance was analyzed.The expression of CD114 on CD123＋CD34＋CD38- cells was further measured to explore the molecular marker of the malignant clone in MDS.Results MDS patients displayed significantly higher proportion of CD34＋CD38-/CD34＋ （（14.03±5.27）%） than normal controls （（7.70±4.36）%, P 〈0.05）.The expression rate of CD123＋CD34＋CD38-/CD34＋CD38- was significantly higher in MDS patients （（48.39±28.15）%） than that in normal controls （（8.75±11.71）%, P 〈0.01）.The expression level of CD123 was significantly correlated with the proportion of bone marrow blasts （r=0.457, P 〈0.05）.The expression rate of CD114＋CD34＋/CD34＋ was lower in MDS patients （（33.05±21.71）%） than that in normal controls （（38.99±19.07）%） but was not statistically significant （P 〉0.05）.The expression of CD114 on CD123＋CD34＋CD38- cells （（34.82±29.58）%） was significantly lower than that on CD123-CD34＋CD38- cells （（53.48±27.41）%） of M DS patients （P 〈0.05）展开更多
In this study the three-dimensional (3-D) model of the ligand-binding domain (V106-P322) of human interleukin-6 receptor (hlL-6 R) was constructed by computer-guided ho-mology modeling technique using the crystal stru...In this study the three-dimensional (3-D) model of the ligand-binding domain (V106-P322) of human interleukin-6 receptor (hlL-6 R) was constructed by computer-guided ho-mology modeling technique using the crystal structure of the ligand-binding domain (K52-L251) of human growth hormone receptor (hGHR) as templet. Furthermore, the active binding region of the 3-D model of hlL-6R with the ligand (hlL-6) was predicted. In light of the structural characteristics of the active region, a hydrophobic pocket shielded by two hydrophilic residues (E115 and E505) of the region was identified by a combination of molecular modelling and the site-directed or double-site mutation of the twelve crucial residues in the ligand-binding domain of hIL-6R (V106-P322). We observed and analyzed the effects of these mutants on the spatial conformation of the pocket-like region of hlL-6 R. The results indicated that any site-directed mutation of the five Cys residues (four conservative Cys residues: Cyst 21, Cys132, Cys165, Cys176; near membrane Cys residue: Cys193) or each double-site mutation of the five residues in WSEWS motif of hIL-6R (V106-P322) makes the corresponding spatial conformation of the pocket region block the linkage between hlL-6 R and hlL-6. However, the influence of the site-directed mutation of Cys211 and Cys277 individually on the conformation of the pocket region benefits the interaction between hlL-6R and hlL-6. Our study suggests that the predicted hydrophobic pocket in the 3-D model of hIL-6R (V106-P322) is the critical molecular basis for the binding of hlL-6R with its ligand, and the active pocket may be used as a target for designing small hlL-6R-inhibiting molecules in our further study.展开更多
基金Ratchadaphiseksomphot Endowment Fund Chulalongkorn University(R/F_2557_021_03_32)Integrated-Innovation Academic Center’Chulalongkorn University Centenary Academic Development Project+1 种基金The 2012 Research Chair GrantThailand National Science and Technology Development Agency(NSTDA)
文摘Injury of the periodontium followed by inflammatory response often leads to mot resorption. Resorption is accomplished by osteoclasts and their generation may depend on an interaction with the cells in direct contact with the root, the cementoblasts. Our study aimed to investigate the role of human cementoblasts in the formation of osteoclasts and the effect of interleukin （IL）- 1β hereupon. Extracted teeth from healthy volunteers were subjected to sequential digestion by type I collagenase and trypsin. The effect of enzymatic digestion on the presence of cells on the root surface was analyzed by histology. Gene expression of primary human cementoblasts （pHCB） was compared with a human cementoblast cell line （HCEM）. The pHCBs were analyzed for their expression of IL-1 receptors as well as of receptor activator of nuclear factor kappa-B ligand （RANKL） and osteoprotegerin （OPG）. In a co-culture system consisting of osteoclast precursors （blood monocytes） and pHCBs, the formation of osteoclasts and their resorptive activity was assessed by osteo-assay and ivory slices. The cells obtained after a 120 min enzyme digestion expressed the highest level of bone sialoprotein, similar to that of HCEM. This fraction of isolated cells also shared a similar expression pattern of IL-1 receptors （ILl-R1 and ILl-R2）. Treatment with IL-11~ potently upregulated RANKL expression but not of OPG. pHCBs were shown to induce the formation of functional osteoclasts. This capacity was significantly stimulated by pretreating the pHCBs with IL-1β prior to their co-culture with human blood monocytes. Our study demonstrated that cementoblasts have the capacity to induce osteoclastogenesis, a capacity strongly promoted by IL-1β. These results may explain why osteoclasts can be formed next to the root of teeth.
基金The Fundacao de Amparo a Pesquisa do Estado de Sao Paulo,No. FAPESP 2010/02991-6
文摘AIM:To investigate hepcidin expression,interleukin-6(IL-6)production and iron levels in the rat colon in the presence of trinitrobenzene sulfonic acid(TNBS)-induced colitis.METHODS:In rats,we evaluated the severity of colitis induced by repeated TNBS administration using macroscopic and microscopic scoring systems and myeloperoxidase activity measurements.The colonic levels of hepcidin,tumor necrosis factor alpha(TNF-α),IL-10 and IL-6 were measured by Enzyme-Linked Immunosorbent Assay,and hepcidin-25 expression and iron deposition were analyzed by immunohistochemistry and the Prussian blue reaction,respectively.Stat-3 phosphorylation was assessed by Western blot analysis.Hematological parameters,iron and transferrin levels,and transferrin saturation were also measured.Additionally,the ability of iron,pathogen-derived molecules and IL-6 to induce hepcidin expression in HT-29 cells was evaluated.RESULTS:Repeated TNBS administration to rats resulted in macroscopically and microscopically detectable colon lesions and elevated colonic myeloperoxidase activity.Hepcidin-25 protein levels were increased in colonic surface epithelia in colitic rats(10.2±4.0pg/mg protein vs 71.0±8.4 pg/mg protein,P<0.01).Elevated IL-6 levels(8.2±1.7 pg/mg protein vs 14.7±0.7 pg/mg protein,P<0.05),TNF-αlevels(1.8±1.2pg/mg protein vs 7.4±2.1 pg/mg protein,P<0.05)and Stat-3 phosphorylation were also observed.Systemic alterations in iron homeostasis,hepcidin levels and anemia were not detected in colitic rats.Iron deposition in the colon was only observed during colitis.Hepcidin gene expression was increased in HT-29 cells after IL-6 and lipopolysaccharide[a toll-like receptor 4(TLR-4)ligand]treatment.Deferoxamine,ferric citrate and peptidoglycan(a TLR-2 ligand)were unable to alter the in vitro expression of hepcidin in HT-29 cells.CONCLUSION:Colitis increased local hepcidin-25 expression,which was associated with the IL-6/Stat-3 signaling pathway.An increase in local iron sequestration was also observed,but additional studies are need
文摘Background Recent studies have shown that interleukin-3 receptor α （CD123） is highly expressed on leukemia stem cells of patients with acute myeloid leukemia, and is correlated with tumor load and poor prognosis.The expression of CD123 may also be high in patients with myelodysplastic syndrome （MDS）.In this study, the expression and clinical significance of CD123 and granulocyte colony stimulating factor （G-CSF） receptor （CD114） on the bone marrow cells of patients with MDS were investigated to explore the molecular marker of the malignant clone of MDS.Methods Forty-two patients with MDS, who were diagnosed in the Hematological Department of General Hospital of Tianjin Medical University from 2008 to 2009, and twelve normal controls were enrolled in this study.Fluorescence activiated cell sorter （FACS） was used to measure the expression of CD123 on CD34＋CD38- cells and CD114 on CD34＋cells of the bone marrow of these patients and controls and the clinical significance was analyzed.The expression of CD114 on CD123＋CD34＋CD38- cells was further measured to explore the molecular marker of the malignant clone in MDS.Results MDS patients displayed significantly higher proportion of CD34＋CD38-/CD34＋ （（14.03±5.27）%） than normal controls （（7.70±4.36）%, P 〈0.05）.The expression rate of CD123＋CD34＋CD38-/CD34＋CD38- was significantly higher in MDS patients （（48.39±28.15）%） than that in normal controls （（8.75±11.71）%, P 〈0.01）.The expression level of CD123 was significantly correlated with the proportion of bone marrow blasts （r=0.457, P 〈0.05）.The expression rate of CD114＋CD34＋/CD34＋ was lower in MDS patients （（33.05±21.71）%） than that in normal controls （（38.99±19.07）%） but was not statistically significant （P 〉0.05）.The expression of CD114 on CD123＋CD34＋CD38- cells （（34.82±29.58）%） was significantly lower than that on CD123-CD34＋CD38- cells （（53.48±27.41）%） of M DS patients （P 〈0.05）
文摘In this study the three-dimensional (3-D) model of the ligand-binding domain (V106-P322) of human interleukin-6 receptor (hlL-6 R) was constructed by computer-guided ho-mology modeling technique using the crystal structure of the ligand-binding domain (K52-L251) of human growth hormone receptor (hGHR) as templet. Furthermore, the active binding region of the 3-D model of hlL-6R with the ligand (hlL-6) was predicted. In light of the structural characteristics of the active region, a hydrophobic pocket shielded by two hydrophilic residues (E115 and E505) of the region was identified by a combination of molecular modelling and the site-directed or double-site mutation of the twelve crucial residues in the ligand-binding domain of hIL-6R (V106-P322). We observed and analyzed the effects of these mutants on the spatial conformation of the pocket-like region of hlL-6 R. The results indicated that any site-directed mutation of the five Cys residues (four conservative Cys residues: Cyst 21, Cys132, Cys165, Cys176; near membrane Cys residue: Cys193) or each double-site mutation of the five residues in WSEWS motif of hIL-6R (V106-P322) makes the corresponding spatial conformation of the pocket region block the linkage between hlL-6 R and hlL-6. However, the influence of the site-directed mutation of Cys211 and Cys277 individually on the conformation of the pocket region benefits the interaction between hlL-6R and hlL-6. Our study suggests that the predicted hydrophobic pocket in the 3-D model of hIL-6R (V106-P322) is the critical molecular basis for the binding of hlL-6R with its ligand, and the active pocket may be used as a target for designing small hlL-6R-inhibiting molecules in our further study.
