Aim Understanding the response of mesenchymal stem cells （MSCs） to mechanical strain and their consequent gene expression patterns will broaden our knowledge of the mechanobiology of distraction osteogenesis. Method...Aim Understanding the response of mesenchymal stem cells （MSCs） to mechanical strain and their consequent gene expression patterns will broaden our knowledge of the mechanobiology of distraction osteogenesis. Methodology In this study, a single period of cyclic mechanical stretch （0.5 Hz, 2,000 με） was performed on rat bone marrow MSCs. Cellular proliferation and alkaline phosphatase （ALP） activity was examined. The mRNA expression of six bone-related genes （Ets-1, bFGF, IGF-Ⅱ, TGF-β, Cbfal and ALP） was detected using real-time quantitative RT-PCR. Results The results showed that mechanical strain can promote MSCs proliferation, increase ALP activity, and up-regulate the expression of these genes. A significant increase in Ets-1 expression was detected immediately after mechanical stimulation, but Cbfal expression became elevated later. The temporal expression pattem of ALP coincided perfectly with Cbfal. Conclusion The results of this study suggest that mechanical strain may act as a stimulator to induce differentiation of MSCs into osteoblasts, and that these bone-related genes may play different roles in the response of MSCs to mechanical stimulation.展开更多
Skin wounds are characterized by injury to the skin due to trauma,tearing,cuts,or contusions.As such injuries are common to all human groups,they may at times represent a serious socioeconomic burden.Currently,increas...Skin wounds are characterized by injury to the skin due to trauma,tearing,cuts,or contusions.As such injuries are common to all human groups,they may at times represent a serious socioeconomic burden.Currently,increasing numbers of studies have focused on the role of mesenchymal stem cell(MSC)-derived extracellular vesicles(EVs)in skin wound repair.As a cell-free therapy,MSC-derived EVs have shown significant application potential in the field of wound repair as a more stable and safer option than conventional cell therapy.Treatment based on MSC-derived EVs can significantly promote the repair of damaged substructures,including the regeneration of vessels,nerves,and hair follicles.In addition,MSC-derived EVs can inhibit scar formation by affecting angiogenesis-related and antifibrotic pathways in promoting macrophage polarization,wound angiogenesis,cell proliferation,and cell migration,and by inhibiting excessive extracellular matrix production.Additionally,these structures can serve as a scaffold for components used in wound repair,and they can be developed into bioengineered EVs to support trauma repair.Through the formulation of standardized culture,isolation,purification,and drug delivery strategies,exploration of the detailed mechanism of EVs will allow them to be used as clinical treatments for wound repair.In conclusion,MSCderived EV-based therapies have important application prospects in wound repair.Here we provide a comprehensive overview of their current status,application potential,and associated drawbacks.展开更多
Liver fibrosis is a significant health burden,marked by the consistent deposition of collagen.Unfortunately,the currently available treatment approaches for this condition are far from optimal.Lysyl oxidase-like prote...Liver fibrosis is a significant health burden,marked by the consistent deposition of collagen.Unfortunately,the currently available treatment approaches for this condition are far from optimal.Lysyl oxidase-like protein 2(LOXL2)secreted by hepatic stellate cells(HSCs)is a crucial player in the cross-linking of matrix collagen and is a significant target for treating liver fibrosis.Mesenchymal stem cell-derived small extracellular vesicles(MSC-sEVs)have been proposed as a potential treatment option for chronic liver disorders.Previous studies have found that MSC-sEV can be used for microRNA delivery into target cells or tissues.It is currently unclear whether microRNA-4465(miR-4465)can target LOXL2 and inhibit HSC activation.Additionally,it is uncertain whether MSC-sEV can be utilized as a gene therapy vector to carry miR-4465 and effectively inhibit the progression of liver fibrosis.This study explored the effect of miR-4465-modified MSC-sEV(MSC-sEVmiR-4465)on LOXL2 expression and liver fibrosis development.The results showed that miR-4465 can bind specifically to the promoter of the LOXL2 gene in HSC.Moreover,MSC-sEVmiR-4465 inhibited HSC activation and collagen expression by downregulating LOXL2 expression in vitro.MSC-sEVmiR-4465 injection could reduce HSC activation and collagen deposition in the CCl4-induced mouse model.MSC-sEVmiR-4465 mediating via LOXL2 also hindered the migration and invasion of HepG2 cells.In conclusion,we found that MSC-sEV can deliver miR-4465 into HSC to alleviate liver fibrosis via altering LOXL2,which might provide a promising therapeutic strategy for liver diseases.展开更多
Cellular strategies remain a crucial component in bone tissue engineering （BTE）. So far, the outcome of cell-based strategies from initial clinical trials is far behind compared to animal studies, which is suggested...Cellular strategies remain a crucial component in bone tissue engineering （BTE）. So far, the outcome of cell-based strategies from initial clinical trials is far behind compared to animal studies, which is suggested to be related to insufficient nutrient and oxygen supply inside the Ussue-engineered constructs. Cocultures, by introducing angiogenic cells into osteogenic cell cultures, might provide a solution for improving vascularization and hence increasing bone formation for cell-based constructs. So far, pre-clinical studies demonstrated that cocultures enhance vascularization and bone formation compared to monocultures. However, there has been no report on the application of cocultures in clinics. Therefore, this mini-review aims to provide an overview regarding （i） critical parameters in cocultures and the outcomes of cocultures compared to monocultures in the currently available pre-clinical studies using human mesenchymal stem cells implanted in orthotopic animal models; and （ii） the usage of monocultures in clinical application in BTE.展开更多
基金supported by grants from the National Nature Science Foundation of China (No. 30772454)Science and Technology Bureau of Sichuan Province (No. 2006z09-013)
文摘Aim Understanding the response of mesenchymal stem cells （MSCs） to mechanical strain and their consequent gene expression patterns will broaden our knowledge of the mechanobiology of distraction osteogenesis. Methodology In this study, a single period of cyclic mechanical stretch （0.5 Hz, 2,000 με） was performed on rat bone marrow MSCs. Cellular proliferation and alkaline phosphatase （ALP） activity was examined. The mRNA expression of six bone-related genes （Ets-1, bFGF, IGF-Ⅱ, TGF-β, Cbfal and ALP） was detected using real-time quantitative RT-PCR. Results The results showed that mechanical strain can promote MSCs proliferation, increase ALP activity, and up-regulate the expression of these genes. A significant increase in Ets-1 expression was detected immediately after mechanical stimulation, but Cbfal expression became elevated later. The temporal expression pattem of ALP coincided perfectly with Cbfal. Conclusion The results of this study suggest that mechanical strain may act as a stimulator to induce differentiation of MSCs into osteoblasts, and that these bone-related genes may play different roles in the response of MSCs to mechanical stimulation.
基金supported by the National Key Research and Development Project Intergovernmental Cooperation in Science and Technology of China(2018YFE0126900)the Key R&D Program of Lishui City(2021ZDYF12)the National Natural Science Foundation of China(82271629)。
文摘Skin wounds are characterized by injury to the skin due to trauma,tearing,cuts,or contusions.As such injuries are common to all human groups,they may at times represent a serious socioeconomic burden.Currently,increasing numbers of studies have focused on the role of mesenchymal stem cell(MSC)-derived extracellular vesicles(EVs)in skin wound repair.As a cell-free therapy,MSC-derived EVs have shown significant application potential in the field of wound repair as a more stable and safer option than conventional cell therapy.Treatment based on MSC-derived EVs can significantly promote the repair of damaged substructures,including the regeneration of vessels,nerves,and hair follicles.In addition,MSC-derived EVs can inhibit scar formation by affecting angiogenesis-related and antifibrotic pathways in promoting macrophage polarization,wound angiogenesis,cell proliferation,and cell migration,and by inhibiting excessive extracellular matrix production.Additionally,these structures can serve as a scaffold for components used in wound repair,and they can be developed into bioengineered EVs to support trauma repair.Through the formulation of standardized culture,isolation,purification,and drug delivery strategies,exploration of the detailed mechanism of EVs will allow them to be used as clinical treatments for wound repair.In conclusion,MSCderived EV-based therapies have important application prospects in wound repair.Here we provide a comprehensive overview of their current status,application potential,and associated drawbacks.
基金supported by the National Natural Science Foundation of China(No.82272421)the Jiangsu Provincial Key Research and Development Program(No.BE2021690)+2 种基金the Changzhou's 14th Five-year Plan Project to Train Highlevel Health Professionals(No.2022CZLJ027)the Scientific Project of Jiangsu Health Commission(No.Z2020038)the Changzhou Sci&Tech Program(No.CJ20220164),China.
文摘Liver fibrosis is a significant health burden,marked by the consistent deposition of collagen.Unfortunately,the currently available treatment approaches for this condition are far from optimal.Lysyl oxidase-like protein 2(LOXL2)secreted by hepatic stellate cells(HSCs)is a crucial player in the cross-linking of matrix collagen and is a significant target for treating liver fibrosis.Mesenchymal stem cell-derived small extracellular vesicles(MSC-sEVs)have been proposed as a potential treatment option for chronic liver disorders.Previous studies have found that MSC-sEV can be used for microRNA delivery into target cells or tissues.It is currently unclear whether microRNA-4465(miR-4465)can target LOXL2 and inhibit HSC activation.Additionally,it is uncertain whether MSC-sEV can be utilized as a gene therapy vector to carry miR-4465 and effectively inhibit the progression of liver fibrosis.This study explored the effect of miR-4465-modified MSC-sEV(MSC-sEVmiR-4465)on LOXL2 expression and liver fibrosis development.The results showed that miR-4465 can bind specifically to the promoter of the LOXL2 gene in HSC.Moreover,MSC-sEVmiR-4465 inhibited HSC activation and collagen expression by downregulating LOXL2 expression in vitro.MSC-sEVmiR-4465 injection could reduce HSC activation and collagen deposition in the CCl4-induced mouse model.MSC-sEVmiR-4465 mediating via LOXL2 also hindered the migration and invasion of HepG2 cells.In conclusion,we found that MSC-sEV can deliver miR-4465 into HSC to alleviate liver fibrosis via altering LOXL2,which might provide a promising therapeutic strategy for liver diseases.
文摘Cellular strategies remain a crucial component in bone tissue engineering （BTE）. So far, the outcome of cell-based strategies from initial clinical trials is far behind compared to animal studies, which is suggested to be related to insufficient nutrient and oxygen supply inside the Ussue-engineered constructs. Cocultures, by introducing angiogenic cells into osteogenic cell cultures, might provide a solution for improving vascularization and hence increasing bone formation for cell-based constructs. So far, pre-clinical studies demonstrated that cocultures enhance vascularization and bone formation compared to monocultures. However, there has been no report on the application of cocultures in clinics. Therefore, this mini-review aims to provide an overview regarding （i） critical parameters in cocultures and the outcomes of cocultures compared to monocultures in the currently available pre-clinical studies using human mesenchymal stem cells implanted in orthotopic animal models; and （ii） the usage of monocultures in clinical application in BTE.
