AIM: To identify the role of herbal compound 861 (Cpd 861) in the regulation of mRNA expression of collagen synthesis- and degradation-related genes in human hepatic stellate cells (HSCs). METHODS: mRNA levels o...AIM: To identify the role of herbal compound 861 (Cpd 861) in the regulation of mRNA expression of collagen synthesis- and degradation-related genes in human hepatic stellate cells (HSCs). METHODS: mRNA levels of collagen types I and III, matrix metalloproteinase 1 (MMP-1), matrix metalloproteinase 2 (MMP-2), membrane type-1 matrix metalloproteinase (MT1-MMP), tissue inhibitor of metalloproteinase 1 (TIMP-1), and transforming growth factor β1 (TGF-β1) in cultured-activated HSCs treated with Cpd 861 or interferon-γ, (IFN-γ,) were determined by real-time PCR. RESULTS: Both Cpd 861 and IFN-γ reduced the mRNA levels of collagen type Ⅲ, MMP-2 and TGF-β1. Moreover, Cpd 861 significantly enhanced the MMP-1 mRNA levels while down-regulated the TIMP-1 mRNA expression, increasing the ratio of MMP-1 to TIMP-1 to (6.3 + 0.3)- fold compared to the control group. CONCLUSION: The anti-fibrosis function of Cpd 861 may be mediated by both decreased interstitial collagen sythesis by inhibiting the transcription of collagen type Ⅲ and TGF-β1 and increased degradation of these collagens by up-regulating MMP-1 and down-regulating TIMP-1 mRNA levels.展开更多
Biomimetic scaffolds are appealing products for the repair of bone defects using tissue engineering strategies.In the present study,novel biomimetic composite scaffolds,with similar properties to natural bone,were pre...Biomimetic scaffolds are appealing products for the repair of bone defects using tissue engineering strategies.In the present study,novel biomimetic composite scaffolds,with similar properties to natural bone,were prepared,blended and cross-linked with bioactive glass,type I collagen and phosphatidylserine.When exposed to cell culture solution in the absence of a cellular source,the composite scaffolds form crystals with octahedral structure.These crystals are similar to the products derived from MC3T3-E1 cell mineralization within the composite scaffolds,with respect to both composition and morphology.Furthermore,crystals with octahedral structure were observed to develop into plate-like hydroxyapatite.The bio-mineralization behavior of the composite scaffolds is likely influenced by inorganic components.Finally,a rabbit tibia defect model shows that the highly bioactive properties of the investigated composites result in excellent bone repair.展开更多
To study the influence of stress relaxation plate on disorganization and repair of the cortex beneath the plate. Methods: A washer made of viscoelastic polyethylene was placed between the screw and the screw hole o...To study the influence of stress relaxation plate on disorganization and repair of the cortex beneath the plate. Methods: A washer made of viscoelastic polyethylene was placed between the screw and the screw hole of conventional stainless rigid plate (RP) to produce a stress relaxation plate (SRP). Both SRP and RP were applied to osteotomized tibia in 48 New Zealand rabbits. Healing process of the fracture with either SRP or RP fixation (control) was comparatively studied with polarized light microscopy, in situ hybridization of collagen mRNA and immunohistochemical technique from 2 to 36 weeks postoperatively. Results: The study of plated bone remodeling showed that the degree of cortex osteoporosis beneath the plate was similar between the SRP and RP group within 12 weeks postoperatively. In comparison, the disorganization of bone structure in SRP group happened later and milder than that of RP group, and the repair process began at 12 weeks after implantation. As a consequence, the absorption cavities became smaller and the structure of collagen fibers became well oriented along with these changes by polarized light microscopy. In addition to these, the in situ hybridization analysis of collagen genes and the immunohistochemical study of type Ⅰ, Ⅲ collagen showed that the osteoblasts lying on the surface of absorption cavities expressed and synthesized type Ⅰ collagen at 8 to 12 weeks after implantation. From this time on, the changes above became more evident significantly before most of cavities were repaired by 36 weeks. In contrast to the changes in the SRP group, no expression and synthesis of any kind of collagen could be observed during 12 to 36 weeks after implantation in RP group. Conclusions: Without removal of the bone plate, the SRP fixation not only reduces the degree of plated bone osteoporosis, but also makes the disorganized bone structure restored to normal in terms of the expression and synthesis of type Ⅰ collagen mRNA of osteoblasts lying on the surface of absorption cavities.展开更多
The objective of this paper is to design a based on composite membrane with certain mechanical porous polyvinyl alcohol (PVA) strength and biocompatibilities serving as tissue regenerative scaffolds. PVA-glycosamino...The objective of this paper is to design a based on composite membrane with certain mechanical porous polyvinyl alcohol (PVA) strength and biocompatibilities serving as tissue regenerative scaffolds. PVA-glycosaminoglycan (GAG)-type I collagen (COL) composite membrane was fabricated by PVA with different molecular weight (Mw) and alcoholysis degree (AD) being blended with certain amounts of GAG and COL and dried at 38~C for 24 h. The water content of the composite membranes were from 61.9% to 95.1% and swelling ratio ranged from 123.6% to 621.7%. Scanning electron micro- scope (SEM) analysis proved that PVA-GAG-COL composite membrane has porous and homogenous structure. Biocompatibility test results showed that the composite membrane was nontoxic, which could promote adhesion and proliferation of fibroblasts on the com- posite membrane. In conclusion, PVA-GAG-COL composite membrane with high water content and swelling ratio, suitable mechanical strength and good biocompatibility, has potential in tissue engineering and regenerative medicine.展开更多
文摘AIM: To identify the role of herbal compound 861 (Cpd 861) in the regulation of mRNA expression of collagen synthesis- and degradation-related genes in human hepatic stellate cells (HSCs). METHODS: mRNA levels of collagen types I and III, matrix metalloproteinase 1 (MMP-1), matrix metalloproteinase 2 (MMP-2), membrane type-1 matrix metalloproteinase (MT1-MMP), tissue inhibitor of metalloproteinase 1 (TIMP-1), and transforming growth factor β1 (TGF-β1) in cultured-activated HSCs treated with Cpd 861 or interferon-γ, (IFN-γ,) were determined by real-time PCR. RESULTS: Both Cpd 861 and IFN-γ reduced the mRNA levels of collagen type Ⅲ, MMP-2 and TGF-β1. Moreover, Cpd 861 significantly enhanced the MMP-1 mRNA levels while down-regulated the TIMP-1 mRNA expression, increasing the ratio of MMP-1 to TIMP-1 to (6.3 + 0.3)- fold compared to the control group. CONCLUSION: The anti-fibrosis function of Cpd 861 may be mediated by both decreased interstitial collagen sythesis by inhibiting the transcription of collagen type Ⅲ and TGF-β1 and increased degradation of these collagens by up-regulating MMP-1 and down-regulating TIMP-1 mRNA levels.
基金supported by the Science and Technology Plan Project of Fujian Department of Education,China (Grant No. JK2009021)
文摘Biomimetic scaffolds are appealing products for the repair of bone defects using tissue engineering strategies.In the present study,novel biomimetic composite scaffolds,with similar properties to natural bone,were prepared,blended and cross-linked with bioactive glass,type I collagen and phosphatidylserine.When exposed to cell culture solution in the absence of a cellular source,the composite scaffolds form crystals with octahedral structure.These crystals are similar to the products derived from MC3T3-E1 cell mineralization within the composite scaffolds,with respect to both composition and morphology.Furthermore,crystals with octahedral structure were observed to develop into plate-like hydroxyapatite.The bio-mineralization behavior of the composite scaffolds is likely influenced by inorganic components.Finally,a rabbit tibia defect model shows that the highly bioactive properties of the investigated composites result in excellent bone repair.
文摘To study the influence of stress relaxation plate on disorganization and repair of the cortex beneath the plate. Methods: A washer made of viscoelastic polyethylene was placed between the screw and the screw hole of conventional stainless rigid plate (RP) to produce a stress relaxation plate (SRP). Both SRP and RP were applied to osteotomized tibia in 48 New Zealand rabbits. Healing process of the fracture with either SRP or RP fixation (control) was comparatively studied with polarized light microscopy, in situ hybridization of collagen mRNA and immunohistochemical technique from 2 to 36 weeks postoperatively. Results: The study of plated bone remodeling showed that the degree of cortex osteoporosis beneath the plate was similar between the SRP and RP group within 12 weeks postoperatively. In comparison, the disorganization of bone structure in SRP group happened later and milder than that of RP group, and the repair process began at 12 weeks after implantation. As a consequence, the absorption cavities became smaller and the structure of collagen fibers became well oriented along with these changes by polarized light microscopy. In addition to these, the in situ hybridization analysis of collagen genes and the immunohistochemical study of type Ⅰ, Ⅲ collagen showed that the osteoblasts lying on the surface of absorption cavities expressed and synthesized type Ⅰ collagen at 8 to 12 weeks after implantation. From this time on, the changes above became more evident significantly before most of cavities were repaired by 36 weeks. In contrast to the changes in the SRP group, no expression and synthesis of any kind of collagen could be observed during 12 to 36 weeks after implantation in RP group. Conclusions: Without removal of the bone plate, the SRP fixation not only reduces the degree of plated bone osteoporosis, but also makes the disorganized bone structure restored to normal in terms of the expression and synthesis of type Ⅰ collagen mRNA of osteoblasts lying on the surface of absorption cavities.
基金National Natural Science Foundation of China,grant number:51070853Guangzhou Technology Plans,grant number:2010B103315 and 2010J-E041
文摘The objective of this paper is to design a based on composite membrane with certain mechanical porous polyvinyl alcohol (PVA) strength and biocompatibilities serving as tissue regenerative scaffolds. PVA-glycosaminoglycan (GAG)-type I collagen (COL) composite membrane was fabricated by PVA with different molecular weight (Mw) and alcoholysis degree (AD) being blended with certain amounts of GAG and COL and dried at 38~C for 24 h. The water content of the composite membranes were from 61.9% to 95.1% and swelling ratio ranged from 123.6% to 621.7%. Scanning electron micro- scope (SEM) analysis proved that PVA-GAG-COL composite membrane has porous and homogenous structure. Biocompatibility test results showed that the composite membrane was nontoxic, which could promote adhesion and proliferation of fibroblasts on the com- posite membrane. In conclusion, PVA-GAG-COL composite membrane with high water content and swelling ratio, suitable mechanical strength and good biocompatibility, has potential in tissue engineering and regenerative medicine.