Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Ultrasound Med Biol ; 47(7): 1775-1784, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33931285

RESUMEN

Modulation of intra-cellular calcium by ultrasound offers a possible means for therapeutic applications. One such possibility is the modulation of nucleus pulposus cells as a preventive measure for inter-vertebral disc degeneration. We report a cellular stimulation device (micro-pipette ultrasound) using a glass micro-pipette as a waveguide to deliver ultrasound through the pipette tip and to elevate intra-cellular calcium in nucleus pulposus cells. The device generates two relevant stimuli at the cellular level: ultrasound propagation throughout the cell and acoustic streaming on the apical side. Ultrasound is radiated from a tip of a few microns, and its amplitude is proportional to the input voltage; acoustic streaming can be controlled by the duty factor. The novelty of the device is to impose a unique cellular loading: shear stress on cell apical surfaces combined with compressional waves propagating through the cells. G protein-coupled receptors and acid-sensing ion channel 3 were shown to play a role in calcium elevation by micro-pipette ultrasound in nucleus pulposus cells. Our results demonstrate that micro-pipette ultrasound can be an effective tool to elevate intra-cellular calcium levels in different cells, facilitating the identification of different mechanoreceptors in action.


Asunto(s)
Calcio/metabolismo , Núcleo Pulposo/metabolismo , Núcleo Pulposo/efectos de la radiación , Ondas Ultrasónicas , Animales , Bovinos , Células Cultivadas , Técnicas Citológicas/instrumentación , Técnicas Citológicas/métodos , Núcleo Pulposo/citología
2.
Sci Rep ; 8(1): 11654, 2018 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-30076336

RESUMEN

Intervertebral disc (IVD) degeneration is associated with imbalances between catabolic and anabolic responses, regulated by extracellular matrix (ECM)-modifying enzymes such as matrix metalloproteinases (MMPs) and their endogenous tissue inhibitors of metalloproteinases (TIMPs). Potential contributing factors, such as interleukin (IL)-1ß and tumor necrosis factor (TNF)-α, derived from infiltrated, activated macrophages within IVD tissues, can trigger abnormal production of ECM-modifying enzymes and progression of IVD degeneration. Novel therapies for regulating ECM-modifying enzymes can prevent or ameliorate IVD degeneration. Photobiomodulation (PBM), known to regulate wound repair, exhibits regenerative potential by modulating biological molecules. This study examined the effects of PBM, administered at various wavelengths (630, 525, and 465 nm) and energy densities (16, 32, and 64 J/cm2), on the production of ECM-modifying enzymes in replicated degenerative IVD. Our results showed that PBM selectively inhibited the production of ECM-modifying enzymes in a dose- and wavelength-dependent manner, suggesting that it could be a novel tool for treating symptomatic IVD degeneration.


Asunto(s)
Matriz Extracelular/enzimología , Degeneración del Disco Intervertebral/terapia , Terapia por Luz de Baja Intensidad , Núcleo Pulposo/enzimología , Progresión de la Enfermedad , Matriz Extracelular/efectos de la radiación , Regulación de la Expresión Génica/efectos de la radiación , Humanos , Interleucina-1beta/genética , Disco Intervertebral/enzimología , Disco Intervertebral/patología , Disco Intervertebral/efectos de la radiación , Degeneración del Disco Intervertebral/genética , Degeneración del Disco Intervertebral/patología , Macrófagos/patología , Macrófagos/efectos de la radiación , Metaloproteinasas de la Matriz/genética , Metaloproteinasas de la Matriz/efectos de la radiación , Núcleo Pulposo/patología , Núcleo Pulposo/efectos de la radiación , Cultivo Primario de Células , Inhibidores Tisulares de Metaloproteinasas/genética , Inhibidores Tisulares de Metaloproteinasas/efectos de la radiación , Factor de Necrosis Tumoral alfa/genética
3.
J Int Med Res ; 45(2): 462-470, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28173722

RESUMEN

Objective To investigate changes in nucleus pulposus cell expression and secretion of interleukin (IL)-1ß and tumour necrosis factor (TNF)-α following stimulation with a low-frequency (LF) pulsed electromagnetic field (PEMF). Methods Primary rat nucleus pulposus cells were isolated and cultured in vitro, followed by stimulation with LF-PEMFs at a frequency of 2 Hz and different intensities, ranging from 0.5-3.0 A/m. Cells were observed for morphological changes, and proliferation rates were measured by cell viability counts. Expression of IL-1ß and TNF-α within the nucleus pulposus cells was measured using western blotting, and levels of IL-1ß and TNF-α secreted in the culture media were measured using enzyme-linked immunosorbent assay. Results Stimulation of nucleus pulposus cells with LF-PEMFs did not appear to affect cell morphology or nucleus pulposus cell IL-1ß and TNF-α expression levels. LF-PEMFs did not significantly affect cell proliferation, however, levels of IL-1ß and TNF-α secreted into the culture media were found to be significantly reduced in an intensity-dependent manner. Conclusion Low-frequency PEMF stimulation may inhibit secretion of IL-1ß and TNF-α in cultured nucleus pulposus cells.


Asunto(s)
Condrocitos/efectos de la radiación , Campos Electromagnéticos , Interleucina-1beta/antagonistas & inhibidores , Núcleo Pulposo/efectos de la radiación , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Animales , Proliferación Celular/efectos de la radiación , Supervivencia Celular/efectos de la radiación , Condrocitos/citología , Condrocitos/metabolismo , Relación Dosis-Respuesta en la Radiación , Radiación Electromagnética , Expresión Génica , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Masculino , Núcleo Pulposo/citología , Núcleo Pulposo/metabolismo , Cultivo Primario de Células , Ratas , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
4.
Spine (Phila Pa 1976) ; 41(5): E248-54, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26571160

RESUMEN

STUDY DESIGN: In vitro experimental study. OBJECTIVE: To investigate the effect of low-intensity pulsed ultrasound (LIPUS) on the extracellular matrix (ECM) synthesis of degenerative human nucleus pulposus cells and explore the molecular mechanism. SUMMARY OF BACKGROUND DATA: LIPUS has been used successfully for bone fracture healing and been proved to be effective in stimulating ECM metabolism in animal intervertebral disc cells. However, whether LIPUS also exerts an anabolic effect on degenerative human nucleus pulposus cells and the possible molecular mechanism is still unclear. METHODS: The degenerative human nucleus pulposus cells were cultured in calcium alginate beads. In the LIPUS group, cells were exposed to an average temporal intensity of 30  mW/cm2 and a frequency of 1.5  MHz of LIPUS 20 minutes daily for 1 week. The control group was cultured in the same way but without LIPUS stimulation. The LY294002 group was stimulated by LIPUS and treated with LY294002 simultaneously. The expression of aggrecan, collagen-II, Sox9, tissue inhibitor of metalloproteinase-,1 and matrix metalloproteinase-3 were evaluated by Enzyme-Linked Immunosorbent Assay, Western blot or RT-PCR. Expression of signaling proteins involved in FAK/PI3K/Akt pathway was studied by Western blot analysis. RESULTS: LIPUS significantly upregulated expression of aggrecan, collagen-II, Sox9, and tissue inhibitor of metalloproteinase-1 compared with control group, but inhibited secretion of matrix metalloproteinase-3. The study further demonstrated that the upregulation of aggrecan, collagen-II, and Sox9 was related to the activation of focal adhesion kinase (FAK)//PI3K/Akt pathway caused by LIPUS. Moreover, inhibition of PI3K/Akt significantly suppressed the special biological effect activated by LIPUS. CONCLUSION: LIPUS promotes the ECM synthesis of degenerative human nucleus pulposus cells through activation of FAK/PI3K/Akt pathway. LEVEL OF EVIDENCE: N/A.


Asunto(s)
Matriz Extracelular/efectos de la radiación , Proteína-Tirosina Quinasas de Adhesión Focal/efectos de la radiación , Núcleo Pulposo/efectos de la radiación , Fosfatidilinositol 3-Quinasas/efectos de la radiación , Proteínas Proto-Oncogénicas c-akt/efectos de la radiación , Ondas Ultrasónicas , Adulto , Células Cultivadas , Matriz Extracelular/metabolismo , Femenino , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Núcleo Pulposo/citología , Núcleo Pulposo/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/fisiología , Transducción de Señal/efectos de la radiación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA