RESUMEN
The purpose of the present study was to investigate the effect of laser irradiation on calcified nodule formation in human dental pulp (HDP) cells. HDP cells were irradiated once with a Ga-Al-As laser for 5 and 10 min, and calcified nodule formation was determined by von Kossa staining. The laser irradiation increased the number of calcified nodules in a time-dependent manner. The activity of alkaline phosphatase and production of collagen and osteocalcin in conditioned medium were measured. Both were higher in the irradiated group than in the nonirradiated group. These results suggested that formation of calcified nodules in HDP cells, as well as in alkaline phosphatase activity, the production of collagen and osteocalcin were enhanced by laser irradiation.
Asunto(s)
Calcificaciones de la Pulpa Dental/etiología , Pulpa Dental/efectos de la radiación , Fibroblastos/efectos de la radiación , Rayos Láser/efectos adversos , Fosfatasa Alcalina/biosíntesis , Células Cultivadas/efectos de la radiación , Colágeno/biosíntesis , Pulpa Dental/citología , Pulpa Dental/metabolismo , Calcificaciones de la Pulpa Dental/metabolismo , Fibroblastos/metabolismo , Galio , Humanos , Osteocalcina/biosíntesisRESUMEN
The plasminogen activator (PA)-plasmin proteolytic system has recently received considerable attention because of its participation in a wide variety of biological activities and in pathological conditions involving tissue destruction. We examined the effects of interleukin-6 (IL-6) on PA activity and the gene expressions of tissue type (t) PA and PA inhibitor-1 (PAI-1) in human dental pulp (HDP) cells. IL-6 treatment induced significantly high PA activity in the HDP cells in a time- and dose-dependent manner, compared with nontreated controls. Western-blot analysis showed that tPA protein in the conditioned medium was stimulated by IL-6, compared with the control. The tPA and PAI-1 mRNA levels were increased in HDP cells treated with IL-6, as shown by reverse transcriptase-polymerase chain reaction. These results suggest that IL-6 stimulated PA activity through an enhancement of tPA gene expression and may be involved in extracellular matrix degradation through the stimulation of the PA-plasmin system of HDP cells.
Asunto(s)
Pulpa Dental/enzimología , Interleucina-6/farmacología , Inhibidor 1 de Activador Plasminogénico/biosíntesis , Inhibidores de Serina Proteinasa/biosíntesis , Activador de Tejido Plasminógeno/biosíntesis , Western Blotting , Células Cultivadas , Medios de Cultivo Condicionados , Pulpa Dental/citología , Inducción Enzimática/efectos de los fármacos , Humanos , Interleucina-6/fisiología , Inhibidor 1 de Activador Plasminogénico/genética , ARN Mensajero/análisis , Inhibidores de Serina Proteinasa/genética , Activador de Tejido Plasminógeno/efectos de los fármacos , Activador de Tejido Plasminógeno/genética , Regulación hacia ArribaRESUMEN
Interleukin-6 (IL-6), which is a multifunctional cytokine, has an important role in acute and chronic inflammation. The peptidoglycan (PG) was purified from Lactobacillus casei, which was a Gram-positive bacteria frequently isolated from deep carious lesions and suspected to be a pathogen of pulpitis. In this study, the effects of PG on the production of IL-6 in human dental pulp cells were examined. PG stimulated IL-6 production in a time- and dose-dependent manner. Reverse transcriptase-polymerase chain reaction experiments showed that the increase was dependent on the enhancement of IL-6 mRNA levels. These findings suggest that Gram-positive bacteria, such as L. casei, from carious lesions, might be involved in developing pulpitis through the stimulation of IL-6 production.
Asunto(s)
Pulpa Dental/efectos de los fármacos , Interleucina-6/biosíntesis , Lacticaseibacillus casei/metabolismo , Peptidoglicano/farmacología , Células Cultivadas , Pulpa Dental/citología , Pulpa Dental/metabolismo , Relación Dosis-Respuesta a Droga , Humanos , Lacticaseibacillus casei/química , Peptidoglicano/metabolismo , Pulpitis/etiología , ARN Mensajero/análisis , Regulación hacia ArribaRESUMEN
Dental pulpal infection is most commonly caused by extensive dental caries. A principal driving force behind pulpal disease response appears to lie in the immune system's response to bacteria. However, the production of interleukin (IL)-1beta and IL-6 in human dental pulp (HDP) cells in response to lipopolysaccharide (LPS) has not been well characterized. We examined IL-1beta and IL-6 production in HDP cells by challenging with LPS from Porphyromonas endodontalis, which is a Gram-negative bacteria found in root canals. Our results presented here showed that when HDP cells were stimulated by LPS, the production of IL-6 always preceded that of IL-1beta. Since the IL-6 production was observed even in the presence of the IL-1beta receptor antagonist, we concluded IL-6 production was independent of the IL-1beta molecule in LPS-stimulated HDP cells. This idea was further supported by the results obtained from RT-PCR experiments, in which IL-6 mRNA, but not IL-1beta mRNA, was present in the RNA preparation isolated from the early stage of cells.