RESUMEN
To investigate the effects of proteins products of endothelial cells (ECs) on the annulus fibrosus (AF) cell metabolism in an in vitro culture. Human AF cells were expanded in monolayer cultures and treated with proteins from the medium of cell line HMEC-1 (Human Microvascular Endothelial Cells) (125µg/ml). After 72h of treatment RNA was isolated from AF cells for analysis of gene expression and the culture medium was collected for protein expression analysis. The qRT-PCR analysis demonstrated increased gene expression of matrix metalloproteinases (MMPs) in AF cells treated with protein products of endothelial cells compared with cells from control group of AF cells: MMP-1 243.10 times (p<0.05), MMP-2 1.37 time (p<0.05), MMP-3 39.83 times (p<0.05) and MMP-13 5.70 times (p<0.05). In contrast, tissue inhibitors of metalloproteinases (TIMPs) were suppressed; TIMP-2 (0.55 time) (p<0.05) and TIMP-3 (0.60 time) (p<0.05) in the exposed groups. The expression of aggrecan gene (0.83 time) (p<0.05), an important extracellular matrix component, was also reduced. MMP-1 and MMP-3 detection was performed, confirming the results of PCR by Western Blot technique. In this study, we observed that the proteins produced by ECs induced the MMPs expression and suppressed the TIMPs as well as the aggrecan in primary cells of the human intervertebral disc, targeting the development of potential treatments for intervertebral disc degeneration and associated discogenic pain.
Analisar o efeito de produtos proteicos de células endoteliais (CEs) sobre o metabolismo de células de ânulo fibroso (AF) em ambiente controlado de cultura celular in vitro. Células de AF humano foram expandidas em camada única e tratadas com proteínas obtidas a partir do meio de cultura de células da linhagem celular HMEC-1 (Human Microvascular Endothelial Cells) (125µg/ml). Após 72h de tratamento, isolou-se RNA das células de AF para análise da expressão gênica e coletou-se meio de cultura para análise de expressão proteica. A análise da qRT-PCR demonstrou aumento da expressão gênica das metaloproteinases de matriz (MMPs) nas células de AF tratadas com produtos proteicos das células endoteliais, em comparação com grupo controle de células de AF: MMP-1 243,10 vezes (p < 0,05), MMP-2 1,37 vezes (p < 0,05), MMP-3 39,83 vezes (p < 0,05) e MMP13 5,70 vezes (p < 0,05). Em contraste, os inibidores teciduais das metaloproteinases (TIMPs) apresentaram supressão da expressão gênica de TIMP-2 (0,55 vezes) (p < 0,05) e TIMP-3 (0,60 vezes) (p < 0,05) nos grupos expostos. A expressão do gene agrecan (0,83 vezes) (p < 0,05), componente importante da matriz extracelular, também estava diminuída. Foi realizada detecção de MMP-1 e MMP-3, confirmando os resultados de PCR através de técnica de Western Blot. Neste estudo observamos que proteínas produzidas pelas CEs induziram a expressão de MMPs e suprimiram a expressão de TIMPs e agrecan nas células primárias do disco intervertebral humano, objetivando desenvolvimento de potenciais terapias no tratamento da degeneração do disco intervertebral e dor discogênica associada.
Analizar el efecto de los productos de proteína de las células endoteliales (CEs) en el metabolismo celular del anillo fibroso (AF) en sistema in vitro de cultivo controlado. Las células del AF humano se ampliaron en monocapa y se las trató con las proteínas obtenidas a partir de los medios de cultivo de la línea de células HMEC-1 (Human Microvascular Endothelial Cells) (125µg/ml). Después de 72h de tratamiento, se aisló el ARN de las células de AF para el análisis de la expresión génica y se recogió el medio de cultivo para el análisis de expresión de la proteína. El análisis de qRT-PCR demostró una mayor expresión génica de las metaloproteinasas de matriz (MMP) en las células tratadas con productos de proteína de AF en las células endoteliales, en comparación con el grupo de control de células AF: MMP-1 243,10 veces (p < 0,05), MMP-2 1,37 veces (p < 0,05), MMP-3 39,83 veces (p < 0,05) y MMP-13 5,70 veces (p < 0,05). En contraste, los inhibidores tisulares de las metaloproteinasas (TIMP), presentaron supresión de la expresión del gen TIMP-2 (0,55 veces) (p < 0,05) y TIMP-3 (0,60 veces) (p < 0,05) en los grupos expuestos. La expresión génica de agrecano (0,83 veces) (p < 0,05), importante componente de la matriz extracelular, también se redujo. La detección de MMP-1 y de MMP-3 fue realizada y se confirmaron los resultados de la PCR mediante la técnica Western Blot. En el presente estudio se observó que las proteínas producidas por las CEs indujeron la expresión de MMP y suprimieron la expresión del TIMP y de agrecano en células primarias del disco intervertebral humano, con el objetivo de desarrollar posibles tratamientos para la degeneración del disco intervertebral y el dolor discogénico asociado.
Asunto(s)
Humanos , Disco Intervertebral/citología , Técnicas de Cultivo de Célula , Metaloproteinasas de la Matriz , Células EndotelialesRESUMEN
Intervertebral disc (IVD) degeneration is implicated as a major cause of low back pain. The alternated phenotypes, reduced cell survival, decreased metabolic activity, loss of matrix production and dystrophic mineralization of nucleus pulposus (NP) cells may be key contributors to progressive IVD degeneration. IVD is the largest avascular structure in the body, characterized by low oxygen tension in vivo. Hypoxia-inducible factor (HIF) is a master transcription factor that is induced upon hypoxia and directs coordinated cellular responses to hypoxic environments. This review summarizes relevant studies concerning the involvement of HIF in the regulation of biological behaviors of NP cells. We describe current data on the expression of HIF in NP cells and further discuss the various roles that HIF plays in the regulation of the phenotype, survival, metabolism, matrix production and dystrophic mineralization of NP cells. Here, we conclude that HIF may be a promising target for the prevention and treatment of IVD degeneration.
Asunto(s)
Animales , Humanos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Supervivencia Celular , Matriz Extracelular/metabolismo , Factor 1 Inducible por Hipoxia/genética , Disco Intervertebral/citología , Degeneración del Disco Intervertebral/metabolismoRESUMEN
To find a new source of seed cells for constructing tissue-engineered intervertebral disc, nucleus pulposus (NP) cells and mesenchymal stem cells (MSCs) were isolated from New Zealand white rabbits. The nucleus pulposus cells population was fluorescence-laelled and co-cultured with MSCs with or without direct contact. Morphological changes were observed every 12 h. Semi-quantitative reverse transcriptase-polymerase chain reaction was performed to assess the expression levels of Sox-9, aggreacan and type II collagen every 24 h after the co-culture. MSCs treated with direct contact rounded up and presented a ring-like appearance. The expression of marker genes was significantly increased when cells were co-cultured with direct contact for 24 h. No significant change was found after coculture without direct contact. Co-culture of NP cells and MSCs with direct contact is a reliable method for generating large amount of NP cells used for cell-based tissue engineering therapy.