RESUMEN
Tissues surrounding dental implants and teeth develop clinical inflammation in response to microbial stimuli. However, the literature suggests that differences exist in the microbial insult and inflammatory responses leading to gingivitis and peri-implant mucositis. In this pilot study, the authors use for the first time a systems biology approach to comprehensively evaluate clinical parameters, selected inflammatory markers, and the microbiome of subject-matched tooth and implant sites during native inflammation and in response to experimental plaque accumulation. Fifteen subjects with 2 posterior implants and corresponding contralateral teeth were examined at enrollment; at day 0, after reinstitution of gingival/mucosal health; at days 7, 14, and 21, during stent-mediated oral hygiene (OH) abstention; and at day 42, after resumption of OH. The subgingival microbiome was evaluated via 16S rRNA gene sequencing and 8 selected inflammatory markers measured in crevicular fluid. Comparison of teeth and implants via general linear models based on orthogonal polynomials showed similar responses in clinical parameters, inflammatory mediators, and proportions of individual microbial taxa during OH abstention. Implants, however, accumulated less plaque and underwent more heterogeneous shifts in microbiome structure. A multilevel, within-group, sparse partial least squares analysis of covariation of microbial, inflammatory, and clinical parameters throughout all study visits found inflammation around teeth and implants positively correlated with IL-1 alpha and IL-1 beta and with the proportions of Selenomonas, Prevotella, and 5 species-level phylotypes. Gingivitis, however, showed a stronger positive correlation with lactoferrin and IL-1ra and a stronger negative correlation with Rothia. Peri-implant mucositis, on the contrary, correlated positively with certain microbial taxa not associated with gingivitis by a previous study or the current one. In summary, differences existed between implants and tooth sites in microbiome evolution during OH abstention and in the correlation of specific inflammatory mediators and microbial taxa with clinical inflammation. Common biological features, however, were also identified for gingivitis and mucositis.
Asunto(s)
Gingivitis/microbiología , Microbiota , Periimplantitis/microbiología , Estomatitis/microbiología , Biomarcadores/análisis , Placa Dental/inmunología , Placa Dental/microbiología , Gingivitis/inmunología , Humanos , Microbiota/genética , Periimplantitis/inmunología , ARN Ribosómico 16S/genética , Estomatitis/inmunologíaRESUMEN
In type 1 diabetes (T1D), a Toll-like receptor (TLR)-hyper-inflammatory monocytic phenotype has been implicated as a mechanism of exacerbated tissue destruction. Other cells of the periodontium, including oral epithelial cells (OECs), express innate immune receptors, including TLRs. To delineate the TLR responses of OECs derived from T1D participants and to determine effects of the anti-inflammatory agent triclosan on the TLR-hyper-inflammatory phenotype, primary human OECs from individuals with T1D and diabetes-free individuals were stimulated with TLR ligands in the presence and/or absence of triclosan. The expression of pro-inflammatory cytokines and micro-RNAs (miRNAs) was evaluated. While the repertoire of TLRs expressed by OECs is similar to that expressed by macrophages (M), the relative amounts and ratios are significantly different. OECs demonstrate a TLR-response profile similar to that of M, yet attenuated. OECs have a unique response to P. gingivalis LPS, where miR146a and miR155 play a regulatory role in responsiveness. OECs from T1D participants are TLR-hyper-responsive, due to dysregulated induction of miR146a and miR155, which is abrogated by pre-treatment with triclosan. The aberrant TLR-activation of OECs in T1D has the potential to contribute to excessive soft- and hard-tissue destruction. Importantly, triclosan's anti-inflammatory property is effective in abrogating TLR-induced OEC hyperactivity.
Asunto(s)
Diabetes Mellitus Tipo 1/inmunología , Mucosa Bucal/inmunología , Receptores Toll-Like/inmunología , Adolescente , Adulto , Anciano , Antiinflamatorios/farmacología , Técnicas de Cultivo de Célula , Células Cultivadas , Células Epiteliales/inmunología , Humanos , Inmunidad Innata/inmunología , Mediadores de Inflamación/análisis , Interleucina-8/análisis , Ligandos , Lipopolisacáridos/inmunología , Macrófagos/inmunología , MicroARNs/análisis , Persona de Mediana Edad , Mucosa Bucal/citología , Fenotipo , Porphyromonas gingivalis/inmunología , Receptor Toll-Like 1/análisis , Receptor Toll-Like 2/análisis , Receptor Toll-Like 4/análisis , Receptor Toll-Like 6/análisis , Factor de Crecimiento Transformador beta1/análisis , Triclosán/farmacología , Adulto JovenRESUMEN
UNLABELLED: Periodontal diseases are a class of pathologies wherein oral microbes induce harmful immune responses in a susceptible host. Therefore, an agent that can both reduce microbial burden and lessen pathogenesis of localized inflammation would have beneficial effects in periodontal disease; 2,4,4-trichloro-2-hydroxydiphenyl-ether [triclosan] is currently used in oral care products owing to broad spectrum antimicrobial and anti-inflammatory properties. OBJECTIVE: To determine effects of triclosan on the response of oral epithelial cells to stimulation with the inflammatory microbial product lipopolysaccharide (LPS), a ligand for toll-like receptor 4 [TLR4]. MATERIALS/METHODS: Primary human oral epithelial cells were stimulated with LPS in the presence and/or absence of triclosan after which expression of pro-inflammatory cytokines, ß-defensins, micro-RNAs [miRNAs], or TLR-signaling pathway proteins were evaluated. RESULTS: Here, we demonstrate that triclosan is a potent inhibitor of oral epithelial cell LPS-induced pro-inflammatory responses by inducing miRNA regulation of the TLR-signaling pathway. Triclosan was not a pan-suppresser of oral epithelial cell responses as ß-defensin 2 [ßD2] and ßD3 were upregulated by triclosan following LPS-stimulation. CONCLUSIONS: These data demonstrate both a novel antimicrobial mechanism by which triclosan improves plaque control and an additional anti-inflammatory property, which could have beneficial effects in periodontal disease resolution.
Asunto(s)
Antiinfecciosos/farmacología , Antiinflamatorios/farmacología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/fisiología , Inflamación/prevención & control , Triclosán/farmacología , Células Cultivadas , Humanos , Lipopolisacáridos/farmacologíaRESUMEN
BACKGROUND: The goal of this study was to assess whether non-smoking patients with type 2 diabetes present with increased levels of local and systemic proinflammatory mediators and, if so, whether such an increase is associated with enhanced clinical gingival inflammation compared to non-smoking patients without diabetes. METHODS: We used a cross-sectional database consisting of 725 self-reported lifelong non-smokers aged 53 to 74 years. Gingival crevicular fluid (GCF) levels of interleukin (IL)-1beta and prostaglandin E(2) (PGE(2)) and serum levels of IL-6 were measured using enzyme-linked immunosorbent assay. No participant had probing depth >3 mm. Participants with bleeding on probing (BOP) in <10% of sites were classified as healthy, whereas those with BOP in >or=10% of sites were defined as having biofilm-gingival interface (BGI) gingivitis. RESULTS: Approximately 53% (n = 385) and 11% (n = 80) of the sample had BGI gingivitis and type 2 diabetes, respectively. The mean age-adjusted level of GCF IL-1beta was significantly elevated in the diabetic group compared to the non-diabetic group (P = 0.048), but serum IL-6 (P = 0.14) and GCF PGE(2) were not (P = 0.98). The mean GCF IL-1beta and PGE(2) levels were significantly elevated in subjects with BGI gingivitis (136.2 +/- 112.9 ng/ml and 277.2 +/- 187.2 ng/ml, respectively) compared to subjects with gingival health (95.9 +/- 82.9 ng/ml and 205.7 +/- 149.6 ng/ml, respectively), regardless of diabetic status (P <0.001 for both). However, serum IL-6 was elevated in subjects with BGI gingivitis compared to subjects with gingival health only among subjects with diabetes (2.9 +/- 3.2 pg/ml versus 1.5 +/- 1.4 pg/ml; P = 0.008). With the exception of serum IL-6 in subjects without diabetes, an increase in the levels of proinflammatory mediators was associated with increased odds of having BGI gingivitis. The associations were stronger in the diabetic group. CONCLUSIONS: Type 2 diabetes may increase the host inflammatory response to oral biofilm, which, in turn, may exacerbate preconditions associated with gingivitis in susceptible individuals. Furthermore, systemic inflammation, as demonstrated by the increased level of serum IL-6, is associated with BGI gingivitis among non-smoking patients with diabetes.
Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/inmunología , Gingivitis/complicaciones , Gingivitis/inmunología , Mediadores de Inflamación/metabolismo , Anciano , Biopelículas , Estudios Transversales , Placa Dental/complicaciones , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/metabolismo , Dinoprostona/análisis , Dinoprostona/metabolismo , Femenino , Líquido del Surco Gingival/inmunología , Gingivitis/sangre , Gingivitis/metabolismo , Humanos , Interleucina-1beta/análisis , Interleucina-1beta/metabolismo , Interleucina-6/sangre , Masculino , Persona de Mediana Edad , FumarRESUMEN
Dental practitioners must be knowledgeable regarding microbial contamination and biofilm formation in dental unit waterlines. Education should stress the need for improvement in the quality of water delivered to patients during treatment. Manufacturers must also play an important role by providing training and education regarding the proper use and maintenance of their systems. Dental facilities, both public and private, need reliable methods to prevent the development of biofilms within DUWs. These methods must be economical and require minimal effort to use on the part of the dental staff. In order for the system to work efficiently, the effluent water that is produced must be compatible with dental materials and be potentially free from toxic or carcinogenic materials. There are numerous models of water filtration units and chemical flushes available to the dental practitioner. However, the Food and Drug Administration have not approved all products currently on the market. Our evaluation of Zerosil, a new waterline-cleaning product, indicates that it is very easy to use and is extremely effective in killing the commonly found microorganisms in dental unit waterlines, as well as eliminating existing biofilms. It is also economical and requires minimum staff time to keep the waterlines clean. Following the initial treatments during week one, the water emanating from the DUWs was free from any viable microorganisms. This effect was present the entire three weeks in which the waterlines were treated. The elimination of viable microorganisms continued into a fourth study week, even though no further treatment of the DUWs was performed. Although the manufacturer recommends weekly treatment of DUWs following the initial treatment regimen, this result indicates that the product has a longer lasting effect than previously thought. Finally, the product can be delivered through any of the commercially available reservoir/bottle water delivery systems. From our study, Zerosil appears to meet the demanding requirements of keeping dental unit waterlines clean. Based on the research that has been done thus far, no universal treatment protocol can be recommended. A combination of approaches may offer the best available assurance of high-quality dental treatment water. Independent water reservoir systems, when used with a periodic chemical treatment protocol, have demonstrated safety and efficacy. Until we reach a point when a recommendation based on thorough evaluations can be made, dental offices should follow current ADA, OSAP, and CDC guidelines: flush waterlines for two to three minutes at the beginning of each day and for 20 to 30 seconds between each patient, and anti-retraction valves should be installed to prevent oral fluids from being drawn into dental waterlines. It is expected that in the near future, the dental practitioner will have a choice of proven systems and products to deal with this issue. Until that time, one should carefully evaluate any product or system being considered to prevent the formation of biofilms in DUWs.
Asunto(s)
Equipo Dental/microbiología , Contaminación de Equipos/prevención & control , Microbiología del Agua , Biopelículas/efectos de los fármacos , Candida albicans/efectos de los fármacos , Recuento de Colonia Microbiana , Desinfectantes/uso terapéutico , Enterococcus faecalis/efectos de los fármacos , Diseño de Equipo , Escherichia coli/efectos de los fármacos , Humanos , Control de Infección Dental , Klebsiella pneumoniae/efectos de los fármacos , Guías de Práctica Clínica como Asunto , Proteus mirabilis/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Control de Calidad , Staphylococcus aureus/efectos de los fármacos , Purificación del Agua/instrumentación , Purificación del Agua/métodosRESUMEN
Gallium, a group IIIa metal salt, has been demonstrated to be an effective immunosuppressive agent. Gallium has also been shown to inhibit the production of inflammatory cytokines, such as IL-1beta, produced by macrophage-like cells in vitro. To further characterize the effects of gallium on the inflammatory process, we examined the effects of gallium nitrate on matrix metalloproteinase (MMP) activity utilizing the rabbit synoviocyte cell line HIG-82. HIG-82 cells were incubated with IL-1beta and TPA, with and without increasing concentrations of gallium nitrate. Conditioned medium was collected and assayed for MMP activity using a synthetic substrate and substrate gel zymography. IL-1beta and TPA alone induced MMP activity in HIG-82 cells. A dose-dependent inhibition of IL-1beta and TPA stimulated MMP activity by gallium nitrate at increasing concentrations was observed. This study demonstrates that gallium nitrate can inhibit the activity of MMPs and may be useful as a modulator of inflammation in arthritis.
Asunto(s)
Galio/farmacología , Inmunosupresores/farmacología , Metaloproteinasas de la Matriz/metabolismo , Membrana Sinovial/enzimología , Animales , Línea Celular , Colagenasas/metabolismo , Gelatina/metabolismo , Interleucina-1/farmacología , Conejos , Membrana Sinovial/citología , Membrana Sinovial/efectos de los fármacos , Acetato de Tetradecanoilforbol/farmacologíaRESUMEN
Recent reports demonstrate that tongue bars can cause damage to the dentition. The first known report of attachment loss associated with the presence of a tongue bar is described.
Asunto(s)
Pérdida de Hueso Alveolar/etiología , Pérdida de la Inserción Periodontal/etiología , Punciones/efectos adversos , Lengua , Adulto , Esmalte Dental/lesiones , Estudios de Seguimiento , Cuerpos Extraños/complicaciones , Encía/trasplante , Humanos , Masculino , Bolsa Periodontal/etiología , Colgajos Quirúrgicos , Fracturas de los Dientes/etiologíaRESUMEN
Studies show that implants exhibiting peri-implantitis contain elevated levels of the cytokine interleukin-1 beta in the gingival crevicular fluid (GCF). This study further evaluated possible mechanisms of osseous loss in peri-implantitis by examining GCF samples for the presence of prostaglandin E2 (PGE2) and proteolytic enzymes, specifically matrix metalloproteinases (MMPs). Results indicated that levels of PGE2 in healthy sites were not significantly different from those at diseased sites. MMP species migrated at 92 kd and 66 kd. No qualitative difference in bands was seen between healthy implants and those diagnosed with early peri-implantitis. Results suggested that PGE2 and MMP levels are not useful biologic markers for distinguishing between healthy and diseased implants.
Asunto(s)
Implantes Dentales/efectos adversos , Dinoprostona/análisis , Líquido del Surco Gingival/química , Metaloendopeptidasas/análisis , Periodontitis/inmunología , Pérdida de Hueso Alveolar/enzimología , Pérdida de Hueso Alveolar/etiología , Pérdida de Hueso Alveolar/metabolismo , Biomarcadores , Estudios de Casos y Controles , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Líquido del Surco Gingival/enzimología , Humanos , Interleucina-1/análisis , Periodontitis/etiologíaRESUMEN
The odontoblast is the cell responsible for dentin formation and mineralization during tooth development. A number of primary pulp cell culture systems have been used to study the mechanism of dentinogenesis in vitro. One of the difficulties in using primary cells is the limited number of cell divisions they will undergo. In this study, this problem was addressed by transfecting primary cultures of human pulp cells with an SV40-adenovirus construct. This resulted in the establishment of transformed human pulp cells, which were named HPC-T. A series of preliminary experiments were performed to characterize these cells, including their morphology, cell proliferation, alkaline phosphatase production, and cytogenetic make-up. The results demonstrate that SV40-transformed human pulp cells retain many of the characteristics of the parent primary cells and may be useful in the study of pulp cell function in vitro.
Asunto(s)
Transformación Celular Viral , Pulpa Dental/citología , Dentinogénesis , Fosfatasa Alcalina/biosíntesis , División Celular , Línea Celular , Células Cultivadas , Pulpa Dental/enzimología , Humanos , Cariotipificación , Virus 40 de los SimiosRESUMEN
Interleukin-1 and tumor necrosis factor-alpha are inflammatory cytokines that are known to be potent stimulators of mineralized tissue resorption. One of the mechanisms by which these cytokines induce this loss is through the stimulation of matrix metalloproteinase (MMP) production and secretion by the host cells present at the inflammatory site. We have previously shown that these cytokines have little effect on MMP production by human pulp cells in short-term culture (24 to 48 h). In this study, we examined the production of MMPs by human pulp cells in the presence and absence of interleukin-1 and tumor necrosis factor-alpha in long-term cultures (2 to 16 days) using substrate gel zymography. The major band present in all samples examined migrated at 68 kDa, corresponding to the migration pattern of MMP-2, whereas a minor band migrated at 90 kDa, corresponding to the migration pattern of MMP-9. In the presence of cytokines, elevated levels of MMP-2 and MMP-9 were apparent at days 9 through 16. In addition, a band migrating at 110 kDa was present. This study demonstrates that cytokines stimulate the production of elevated levels of MMPs by human pulp cells in long-term cultures and that these MMPs may play a role in pulpal inflammation.
Asunto(s)
Colagenasas/biosíntesis , Colagenasas/efectos de los fármacos , Pulpa Dental/efectos de los fármacos , Pulpa Dental/enzimología , Gelatinasas/biosíntesis , Gelatinasas/efectos de los fármacos , Interleucina-1/farmacología , Metaloendopeptidasas/biosíntesis , Metaloendopeptidasas/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Células Cultivadas , Colagenasas/análisis , Pulpa Dental/citología , Electroforesis en Gel de Poliacrilamida/métodos , Gelatinasas/análisis , Humanos , Metaloproteinasa 2 de la Matriz , Metaloproteinasa 9 de la Matriz , Metaloendopeptidasas/análisis , Estimulación Química , Especificidad por Sustrato/efectos de los fármacos , Factores de TiempoRESUMEN
BACKGROUND: Infection control training for predoctoral dental students, dental hygiene students, and dental assistant students has assumed an important role in the educational process at our institution. As part of an ongoing review of the curriculum at our school, we conducted a retrospective analysis of reported percutaneous injuries during the years 1991 through 1994 to determine whether the increase in infection control training introduced at the school in 1990 has had an effect on our rate of percutaneous injuries. METHODS: The population examined in this retrospective study consisted of predoctoral and postdoctoral dental students, dental hygiene students, dental assistant students, and staff. The data for this retrospective study were obtained from annual reports of occupational exposures incurred by students and staff. These annual reports were generated by compiling and summarizing all percutaneous injury incident reports that were prepared for that year. RESULTS: Our results indicate, that except for an increase in 1992, the total number and incidence of reported percutaneous injuries decreased from 1991 to 1994. Statistically significant decreases were seen in the total number of reported percutaneous injuries for all students, staff, and all groups combined. On the basis of data available for 1993 and 1994, the incidence of reported percutaneous injuries per 1000 procedures was fairly constant over these 2 years. Distribution of percutaneous injuries by source varied during the 4-year period. CONCLUSIONS: As part of the outcomes assessment program at our institution, we conducted a retrospective study of reported percutaneous injuries from 1991 to 1994. This study demonstrated that, although the total number of injuries decreased significantly, the rates within certain individual groups remained unchanged. On the basis of this observation, increased emphasis in the prevention of percutaneous injuries through additional training is indicated for these groups.
Asunto(s)
Educación en Odontología/normas , Docentes de Odontología , Control de Infecciones , Lesiones por Pinchazo de Aguja/epidemiología , Facultades de Odontología/estadística & datos numéricos , Estudiantes de Odontología , Curriculum , Humanos , Incidencia , Transmisión de Enfermedad Infecciosa de Paciente a Profesional/prevención & control , Lesiones por Pinchazo de Aguja/etiología , Estudios Retrospectivos , Gestión de RiesgosAsunto(s)
Personal de Odontología , Dermatitis por Contacto/etiología , Dermatitis Profesional/etiología , Goma/efectos adversos , Dermatitis por Contacto/diagnóstico , Dermatitis Profesional/diagnóstico , Humanos , Hipersensibilidad Inmediata/diagnóstico , Hipersensibilidad Inmediata/etiología , Pruebas Cutáneas , Urticaria/diagnóstico , Urticaria/etiologíaRESUMEN
Peri-implantitis has been shown to possess clinical characteristics similar to those of periodontitis. This pilot study was conducted to determine levels of inflammatory cytokines in crevicular fluid from healthy implants and those implants affected by peri-implantitis. Fifty implants from 13 patients were examined. A clinical examination was performed, and gingival crevicular fluid samples were collected and analyzed for cytokines. Implants were categorized clinically as healthy, early peri-implantitis, or advanced peri-implantitis. Interleukin-1 beta was detected in the crevicular fluid of implants in all three groups (healthy = 59.47 +/- 15.55 pg/site; early peri-implantitis = 460.77 +/- 35.67 pg/site; and advanced peri-implantitis = 191.10 +/- 21.60 pg/site [mean +/- SEM]). These results indicate that interleukin-1 beta is present in implant gingival crevicular fluid and may be modulating attachment loss in implants suffering from peri-implantitis. Thus, interleukin-1 beta may be used to monitor disease progression.
Asunto(s)
Citocinas/análisis , Implantación Dental Endoósea , Implantes Dentales , Líquido del Surco Gingival/química , Pérdida de Hueso Alveolar/inmunología , Pérdida de Hueso Alveolar/metabolismo , Biomarcadores/análisis , Diseño de Prótesis Dental , Prótesis Dental de Soporte Implantado , Progresión de la Enfermedad , Estudios de Seguimiento , Líquido del Surco Gingival/inmunología , Humanos , Interleucina-1/análisis , Pérdida de la Inserción Periodontal/inmunología , Pérdida de la Inserción Periodontal/metabolismo , Periodontitis/inmunología , Periodontitis/metabolismo , Proyectos Piloto , Factor de Necrosis Tumoral alfa/análisisRESUMEN
Little information is currently known regarding the effects of cytokines and lipopolysaccharides (LPS's) on matrix metalloproteinase (MMP) production by pulp cells in vitro. In this study, human pulp cells (HPC's) and clonal rat pulp cells RPC-C2A were treated with interleukin (IL)-1 alpha, IL-1 beta, tumor necrosis factor (TNF)-alpha, and LPS for 24 h. Conditioned medium and cell lysates were collected and analyzed by gelatin zymography. RPC-C2A cells treated with IL-1 beta and TNF-alpha displayed elevated levels of MMP's in conditioned medium fractions. LPS's at increasing concentrations had a similar effect. HPC's treated with either cytokines or LPS's had no change in the pattern of MMP's produced or secreted in either cellular or conditioned medium fractions. These studies indicate that the effects of cytokines and LPS's on pulp cells are not identical for cells from different species and requires further investigation to clarify these variations.
Asunto(s)
Pulpa Dental/efectos de los fármacos , Pulpa Dental/enzimología , Interleucina-1/farmacología , Lipopolisacáridos/farmacología , Metaloendopeptidasas/biosíntesis , Factor de Necrosis Tumoral alfa/farmacología , Animales , Células Cultivadas , Células Clonales , Pulpa Dental/citología , Escherichia coli/química , Matriz Extracelular/enzimología , Gelatinasas/biosíntesis , Humanos , Mediadores de Inflamación/farmacología , Metaloproteinasa 2 de la Matriz , Ratas , Ratas WistarRESUMEN
Recent work by a number of investigators has demonstrated that the process of bone matrix formation and mineralization is under the influence of growth factors and cytokines present in the local environment. Utilizing primary and established osteoblast cell culture systems, these studies have examined the regulation of bone matrix protein synthesis and deposition into the extracellular matrix (ECM) and subsequent mineralization. In previous studies, we have utilized the human osteoblastic cell line, HOS TE85, to study the effects of Tumor Necrosis Factor-alpha (TNF-alpha) on the regulation of matrix proteins and proteolytic function in monolayer cultures as well as during the development and calcification of ECM formed by HOS TE85 cells during extended culture. Our studies demonstrate that TNF-alpha inhibited formation and mineralization of nodules. In the study reported here, we evaluated the ultrastructural morphology of the cell-matrix complex formed by HOS TE85 cells in the presence and absence of TNF-alpha at selected time points during the matrix development process utilizing both transmission electron microscopy and light microscopy. In the presence of TNF-alpha, the cell-matrix complex does not develop normally, with a lack of organization and mineralization, when compared to untreated cells. The lack of mineralization appears to result from the lack of normal collagen fibril deposition and formation of an appropriate ECM essential for the mineralization process. These results support our previous observations that TNF-alpha inhibits HOS TE85 cells from forming a mineralizing ECM by inhibiting incorporation of collagen into the ECM and inducing the synthesis of proteolytic enzymes capable of degrading collagen in the ECM.
Asunto(s)
Matriz Extracelular/ultraestructura , Osteoblastos/ultraestructura , Factor de Necrosis Tumoral alfa/farmacología , Calcificación Fisiológica , Colágeno/metabolismo , Matriz Extracelular/efectos de los fármacos , Humanos , Microscopía Electrónica , Microscopía Ultravioleta , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Células Tumorales CultivadasRESUMEN
We have followed the synthesis and secretion of urokinase-type plasminogen activator (u-PA) and its inhibitor, PAI-1, and matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMP-1) during differentiation of a human osteoblastic cell line, HOS TE85, and the effect of TNF-alpha on this process. Our results show that the ratio of u-PA/PAI-1 associated with the cell-matrix components increases during differentiation of these cells over a 14-day period. Although TNF-alpha suppresses the induced increase in steady-state mRNA levels of u-PA and PAI-1 during maturation of extracellular matrix (ECM), the u-PA/PAI-1 ratio is altered in such a way that PA activity associated with the ECM is higher than control cells. The expression of MMP-1 is low and remains essentially invariant over a culture period of 14 days. TNF-alpha enhances MMP-1 transcription nearly 12-fold initially, after which mRNA levels drop off but remain significantly higher than the controls. Activities and steady-state mRNA levels of MMP-2 and MMP-9 increase nearly 15-fold during maturation of the ECM, but the level of TIMP-1 mRNA is not appreciably altered. The presence of TNF-alpha suppresses maturation-induced transcription of MMP-2, enhances TIMP-1 transcription, but has little effect on MMP-9 mRNA levels. The data show that chronic exposure to TNF-alpha alters the balance between u-PA/PAI-1 and MMPs/TIMP-1, which favors higher activity of proteinases. Accordingly, the presence of TNF-alpha in chronic inflammatory episodes would be expected to alter bone remodeling by inhibiting maturation of ECM and formation of bone.
Asunto(s)
Matriz Extracelular/fisiología , Glicoproteínas/biosíntesis , Metaloendopeptidasas/biosíntesis , Osteoblastos/citología , Inhibidor 1 de Activador Plasminogénico/biosíntesis , Factor de Necrosis Tumoral alfa/farmacología , Activador de Plasminógeno de Tipo Uroquinasa/biosíntesis , Diferenciación Celular , Medios de Cultivo Condicionados , Inducción Enzimática/efectos de los fármacos , Gelatinasas/biosíntesis , Humanos , Proteínas de Neoplasias/biosíntesis , Osteoblastos/efectos de los fármacos , Osteoblastos/enzimología , Osteosarcoma/patología , ARN Mensajero/biosíntesis , Inhibidores Tisulares de Metaloproteinasas , Células Tumorales CultivadasRESUMEN
A Physiologic State Severity Classification (PSSC) derived from clustering of 17 cardiorespiratory variables was used to predict cytokine response in critically ill posttrauma patients. The PSSC defined physiologic states: A-State (A), normal stress response; B-State (B), metabolic insufficiency; C2-State (C), respiratory insufficiency. Bayesian analysis of these states defined a probability of death (Pdeath). 416 studies from 60 newly studied multiple trauma patients (70% males, Injury Severity Score = 27.5) were analyzed; 45 (75%) had sepsis (s), 28 (47%) had sepsis-adult respiratory distress syndrome (s-ARDS). Of 35 survivors (66% s, 37% s-ARDS, mean Pdeath = .42) 23% were predominantly A, 66% B, and 11% C. Of 25 deaths (88% s, 60% s-ARDS, mean Pdeath = .64) 0% were A, 44% B, and 56% C. PSSC States were correlated with incidence and mean plasma levels (pl) in picograms/mL of cytokines. 23 samples from recovering nonseptic trauma patients were used as controls.
Asunto(s)
Citocinas/sangre , Traumatismo Múltiple/sangre , Índices de Gravedad del Trauma , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Ensayo de Inmunoadsorción Enzimática , Humanos , Masculino , Persona de Mediana Edad , Traumatismo Múltiple/clasificación , Traumatismo Múltiple/mortalidad , Traumatismo Múltiple/terapia , Estudios Retrospectivos , Tasa de SupervivenciaRESUMEN
Heparin has been identified as a potent modulator of bone resorption. Heparin induces osteoporosis during long-term administration and has been shown in vitro to enhance the effects of other bone resorbing factors, including parathyroid hormone. In this study, we examined the effects of heparin on the bone-resorbing activity of the inflammatory cytokine IL-1 beta. Resorption was determined by measuring release of previously incorporated 45Ca from fetal rat long bones cultured in medium supplemented with either 0.1% bovine serum albumin or 10% heat-inactivated fetal calf serum. Heparin, in the absence of serum, decreased basal resorption at 4 and 10 units/ml, and slightly increased resorption at 30 units/ml. Heparin had no effect on IL-1 beta-stimulated resorption. In the presence of serum, heparin induced a two-fold increase in resorption alone, however, when cocultured with IL-1 beta, heparin failed to further enhance IL-1 beta-stimulated resorption.
Asunto(s)
Resorción Ósea/fisiopatología , Huesos/efectos de los fármacos , Heparina/farmacología , Interleucina-1/farmacología , Animales , Huesos/embriología , Femenino , Humanos , Embarazo , Radio (Anatomía)/efectos de los fármacos , Radio (Anatomía)/embriología , Ratas , Ratas Sprague-Dawley , Tibia/efectos de los fármacos , Tibia/embriología , Cúbito/efectos de los fármacos , Cúbito/embriologíaRESUMEN
Homeostatic turnover of bone is believed to be regulated in part by growth factors present in the surrounding environment. The first step during the bone formation process is the recruitment of osteoblasts from the surrounding intact bone to the resorption site. In this study, the effects of TGF-alpha on osteoblast chemotaxis was investigated. Cultures of rat osteoblasts and human osteoblast-like cells were examined for chemotaxis in response to increasing concentrations of TGF-alpha utilizing a modified Boyden Chamber technique. TGF-alpha stimulated a dose-dependent increase in chemotaxis by both cell populations. These results indicate that TGF-alpha may be playing an important role in the early stages of bone matrix regeneration by stimulating osteoblast chemotaxis.