The aim of this work was to develop an in vitro model to study mechanical compression effects on cartilage. A pressure-controlled compression device was used in this study. Cartilage explants obtained from human knee ...The aim of this work was to develop an in vitro model to study mechanical compression effects on cartilage. A pressure-controlled compression device was used in this study. Cartilage explants obtained from human knee were compressed at 1MPa/1Hz for 7 hours (30 min ON, 30 min OFF) under normoxia (5% CO2, 21% O2) or hypoxia (5% CO2, 5% O2). Cell viability was analyzed while nitric oxide (NO) and glycosaminoglycans (GAG) release was assayed in culture media. Mechanical stimulation increased NO production and GAG release by human cartilage explants under normoxia and hypoxia culture. In normoxia and hypoxia conditions, mechanical stimulation alters human OA cartilage metabolism. There is also, an increase in matrix degradation after compression, as shown by levels of GAG found in culture media. This study put in evidence the importance of mechanical compression in the progression of the osteoarthritis and present and in vitro model for mechanobiological and pharmacological studies.展开更多
Tissue engineering is an emerging multidisciplinary field involving surgery medicine, biology, chemistry, mechanics and engineering to improve the health and quality of life by restoring, maintaining or enhancing tiss...Tissue engineering is an emerging multidisciplinary field involving surgery medicine, biology, chemistry, mechanics and engineering to improve the health and quality of life by restoring, maintaining or enhancing tissue and organ function?[6;11]. The principle is simple: cells are collected and introduced -with or without modification of their biological properties- into an environment in which physico-chemical and mechanical parameters are kept stable. When they reach maturity, the biotissue or cells can be grafted. The main parameters are: cells, scaffold, biological molecules and mechanical forces. A combination of these parameters can promote cellular differentiation and proliferation. But it should be emphasized that at this time, signalling pathways and the rationale behind the physiological design remain to be elucidated. Among the main medium-term clinical applications are cardiac insufficiency, atherosclerosis, osteoarthritis, diabetes, liver diseases, bladder, and skin. In this paper the examples of cartilage and vascular engineering will be examined.展开更多
1 Introduction The cartilage i s a hydrated connective tissue in joint s that withstands and distributes mechanical forces.Chondrocytes utilize mechanical signals to maintain tissue homeostasis.They regulate their met...1 Introduction The cartilage i s a hydrated connective tissue in joint s that withstands and distributes mechanical forces.Chondrocytes utilize mechanical signals to maintain tissue homeostasis.They regulate their metabolic activity through complex biological and biophysical interactions with the extracellular matrix(ECM).Although some of the mechanisms of mechanotransduction are known today,there are certainly many others left unrevealed.Different topics of chondrocytes mechanobiology have led to the development of tissue engineering.It is the concept of substitute tissue developed in vitro,from bioresorbable or non2bioresorbable scaffolds and from cells harvested in a physiologic mechanical environment.展开更多
文摘The aim of this work was to develop an in vitro model to study mechanical compression effects on cartilage. A pressure-controlled compression device was used in this study. Cartilage explants obtained from human knee were compressed at 1MPa/1Hz for 7 hours (30 min ON, 30 min OFF) under normoxia (5% CO2, 21% O2) or hypoxia (5% CO2, 5% O2). Cell viability was analyzed while nitric oxide (NO) and glycosaminoglycans (GAG) release was assayed in culture media. Mechanical stimulation increased NO production and GAG release by human cartilage explants under normoxia and hypoxia culture. In normoxia and hypoxia conditions, mechanical stimulation alters human OA cartilage metabolism. There is also, an increase in matrix degradation after compression, as shown by levels of GAG found in culture media. This study put in evidence the importance of mechanical compression in the progression of the osteoarthritis and present and in vitro model for mechanobiological and pharmacological studies.
文摘Tissue engineering is an emerging multidisciplinary field involving surgery medicine, biology, chemistry, mechanics and engineering to improve the health and quality of life by restoring, maintaining or enhancing tissue and organ function?[6;11]. The principle is simple: cells are collected and introduced -with or without modification of their biological properties- into an environment in which physico-chemical and mechanical parameters are kept stable. When they reach maturity, the biotissue or cells can be grafted. The main parameters are: cells, scaffold, biological molecules and mechanical forces. A combination of these parameters can promote cellular differentiation and proliferation. But it should be emphasized that at this time, signalling pathways and the rationale behind the physiological design remain to be elucidated. Among the main medium-term clinical applications are cardiac insufficiency, atherosclerosis, osteoarthritis, diabetes, liver diseases, bladder, and skin. In this paper the examples of cartilage and vascular engineering will be examined.
基金This work was partly supported by region de Lorraine(CPER)andFrench embassyin Beijing
文摘1 Introduction The cartilage i s a hydrated connective tissue in joint s that withstands and distributes mechanical forces.Chondrocytes utilize mechanical signals to maintain tissue homeostasis.They regulate their metabolic activity through complex biological and biophysical interactions with the extracellular matrix(ECM).Although some of the mechanisms of mechanotransduction are known today,there are certainly many others left unrevealed.Different topics of chondrocytes mechanobiology have led to the development of tissue engineering.It is the concept of substitute tissue developed in vitro,from bioresorbable or non2bioresorbable scaffolds and from cells harvested in a physiologic mechanical environment.
