AIM:To explore the functions of Chordin-like 2,which is encoded by CHRDL2,in the process of retinal pigmented epithelium(RPE)differentiation and damage repair.METHODS:The fetal RPE cells(f RPE)was obtained from aborte...AIM:To explore the functions of Chordin-like 2,which is encoded by CHRDL2,in the process of retinal pigmented epithelium(RPE)differentiation and damage repair.METHODS:The fetal RPE cells(f RPE)was obtained from aborted fetus which obeyed medical ethics.Real-time quantitative polymerase chain reaction was used to measure expression quantity of CHRDL2 and other functional genes expression.Knocking down and overexpression was used to analyze the functions about Chordin-like 2.Enzyme-linked immunosorbent assay(ELISA)was used to detect the secretion of bone morphogenetic proteins 4(BMP4).Flow cytometry was used to analyze cell cycle.Cell morphology was observed by phase contrast microscope(PCM).RESULTS:In normal RPE cells,CHRDL2 was firstly upregulated and followed a downregulation but eventually,it was expressed higher than the cells which undergone epithelial-mesenchymal transition(EMT).After knocking down CHRDL2,the secretion of BMP4 was decreased,RPErelated genes(OTX2,MITF,RPE65)were downregulated while EMT-related genes(SNAI1,VIM)were upregulated.However,the expression of these related genes after overexpression of CHRDL2 had contrary results.Chordin-like 2 also regulated the cell cycle by regulating BMP pathway.When CHRDL2 was knocked down,more f RPE cells stayed in S phase of cell cycle,while adding BMP4 reduced the proportion of the cells in S phase.However,overexpression of CHRDL2 increased more BMP4 secretion,this effect decreased the number of cells in S phase,but exogenous BMP inhibitor also could change this effect.At last,in the process of RPE cells differentiation,adding BMP4 at early stage could intervene normal RPE differentiation.Compared with BMP4,inhibiting BMP pathway had no significant negative effect at early stage,but suppressed differentiation at late stage.CONCLUSION:BMP pathway can be activated in a correct temporal order,otherwise,the cells have incorrect differentiation orientation.And Chordin-like 2 plays a role in dynamic regulation of BMP pathway and it also regulates the differentiation of RPE cells.Therefore,this research enlightens a new direction to inhibit EMT and promote cell redifferentiation after injury.展开更多
Cells have intrinsic mechanisms for cleaning harmful oxidants represented mainly by reactive oxygen species (ROS). Despite the antioxidant defense, ROS can cause serious damage to the retina that with age leads to var...Cells have intrinsic mechanisms for cleaning harmful oxidants represented mainly by reactive oxygen species (ROS). Despite the antioxidant defense, ROS can cause serious damage to the retina that with age leads to various eye diseases and even blindness. Among numerous cell sites of ROS generation, mitochondrial electron transport is of crucial importance. Recently, for the purpose of cleaning ROS in the mitochondrial matrix, powerful mitochondria- targeted antioxidant “SkQ1” has been invented. We studied SkQ1 effects upon tissues of rat posterior eye cup that consisted: retinal pigment epithelium (RPE) ? choroidal coat ? scleral coat. The eye cups were isolated from the eyes of adult albino rats and cultivated in rotary tissue culture system in the presence of 20 nM SkQ1 or without this compound. After 7 days - 1 month in vitro eye cup samples were studied by immunohistochemistry, routine histology, morphometry, and digital image analysis. We have found that under chosen, “in vitro like in vivo” conditions 20 nM SkQ1 effectively reduced cell death in RPE and choroid, protected RPE from disintegration caused by cell phenotypic transformation and withdrawal from the layer, suppressed transmigration of choroidal coat cells. In the ex vivo model we used degenerative processes were more pronounced in the eye cup center where SkQ1 effect was most vivid. All this give us hopes for effectiveness of SkQ1 treatment of retinal central part that is very susceptible to light-induced over-oxidation injury and mostly suffering in many age-related diseases, AMD, in particular.展开更多
Diabetic retinopathy(DR)is a common cause of blindness all over the world.Bone marrow mesenchymal stem cells(BMSCs)have been considered as a promising strategy for retinal regeneration in the treatment of DR.However,t...Diabetic retinopathy(DR)is a common cause of blindness all over the world.Bone marrow mesenchymal stem cells(BMSCs)have been considered as a promising strategy for retinal regeneration in the treatment of DR.However,the poor viability and low levels of BMSCs engraftment limit the therapeutic potential of BMSCs.The present study aimed to examine the direct induction of BMSCs differentiation into the cell types related to retinal regeneration by using soluble cytokine ciliary neurotrophic factor(CNTF).We observed remarkably increased expression of cellular retinaldehyde-binding protein(CRALBP)and retinoid isomerohydrolase(RPE65)in BMSCs treated with CNTF in vitro,indicating the directional differentiation of BMSCs into the retinal pigment epithelium(RPE)cells,which are crucial for retinal healing.In vivo,the diabetic rat model was established by use of streptozotocin(STZ),and animals treated with BMSCs+CNTF exhibited better viability and higher delivery efficiency of the transplanted cells than those treated with BMSCs injection alone.Similar to the in-vitro result,treatment with BMSCs and CNTF combined led to the differentiation of BMSCs into beneficial cells(RPE cells),and accelerated retinal healing characterized by the activation of rod photoreceptor cells and phagocytosis function of RPE cells.In conclusion,CNTF contributes to the differentiation of BMSCs into RPE cells,which may help overcome the current stem cell therapy limitations in the field of retinal regeneration.展开更多
To clarify the effects of zinc on the proliferation and apoptosis of cultured human retinal pigment epithelia (RPE) and the expression of caspase 3 in RPE cells. The effect of Zinc on theproliferation of RPE were exa...To clarify the effects of zinc on the proliferation and apoptosis of cultured human retinal pigment epithelia (RPE) and the expression of caspase 3 in RPE cells. The effect of Zinc on theproliferation of RPE were examined with MTT method. TUNEL method was used to detect the apoptosis of RPE cells. Caspase 3 was detected by immunohistochemistry. A concentration of zinc higher than 0.001 μM could inhibit the proliferation of RPE. And the relationship between concentration of zinc higher than 10 μM and growth prohibition rate of RPE cells was dose dependent. All concentrations of zinc including 0.001 μM enhanced the expression of caspase 3 of RPE. But only the concentration of zinc higher than 0.01 μM could induce apoptosis of RPE. It is concluded that zinc could enhance the expression of caspase 3 of RPE cells and induce apoptosis of RPE cells. Caution should be taken when using zinc supplements for the treatment of ARMD patients without deficiency of zinc.展开更多
BACKGROUND Adipose-derived stem cells(ASCs)have been increasingly explored for cell-based medicine because of their numerous advantages in terms of easy availability,high proliferation rate,multipotent differentiation...BACKGROUND Adipose-derived stem cells(ASCs)have been increasingly explored for cell-based medicine because of their numerous advantages in terms of easy availability,high proliferation rate,multipotent differentiation ability and low immunogenicity.In this respect,they have been widely investigated in the last two decades to develop therapeutic strategies for a variety of human pathologies including eye disease.In ocular diseases involving the retina,various cell types may be affected,such as Müller cells,astrocytes,photoreceptors and retinal pigment epithelium(RPE),which plays a fundamental role in the homeostasis of retinal tissue,by secreting a variety of growth factors that support retinal cells.AIM To test ASC neural differentiation using conditioned medium(CM)from an RPE cell line(ARPE-19).METHODS ASCs were isolated from adipose tissue,harvested from the subcutaneous region of healthy donors undergoing liposuction procedures.Four ASC culture conditions were investigated:ASCs cultured in basal Dulbecco's Modified Eagle Medium(DMEM);ASCs cultured in serum-free DMEM;ASCs cultured in serumfree DMEM/F12;and ASCs cultured in a CM from ARPE-19,a spontaneously arising cell line with a normal karyotype derived from a human RPE.Cell proliferation rate and viability were assessed by crystal violet and MTT assays at 1,4and 8 d of culture.At the same time points,ASC neural differentiation was evaluated by immunocytochemistry and western blot analysis for typical neuronal and glial markers:Nestin,neuronal specific enolase(NSE),protein gene product(PGP)9.5,and glial fibrillary acidic protein(GFAP).RESULTS Depending on the culture medium,ASC proliferation rate and viability showed some significant differences.Overall,less dense populations were observed in serum-free cultures,except for ASCs cultured in ARPE-19 serum-free CM.Moreover,a different cell morphology was seen in these cultures after 8 d of treatment,with more elongated cells,often showing cytoplasmic ramifications.Immunofluorescence results and western blot analysis were indicative of ASC neural differentiation.In fact,basal levels of neural markers detected under control conditions significantly increased when cells were cultured in ARPE-19 CM.Specifically,neural marker overexpression was more marked at 8 d.The most evident increase was observed for NSE and GFAP,a modest increase was observed for nestin,and less relevant changes were observed for PGP9.5.CONCLUSION The presence of growth factors produced by ARPE-19 cells in tissue culture induces ASCs to express neural differentiation markers typical of the neuronal and glial cells of the retina.展开更多
OBJECTIVE: To investigate the proliferation and differentiation of cultured corneal stem cells and determine the effect of corneal stem cells cultured on amniotic membranes on the limbal area for treating corneal burn...OBJECTIVE: To investigate the proliferation and differentiation of cultured corneal stem cells and determine the effect of corneal stem cells cultured on amniotic membranes on the limbal area for treating corneal burns. METHODS: The proliferation and differentiation of corneal stem cells in vitro had been examined using colony-forming efficiency and immunohistochemistry. The stem cells had been cultured on amniotic membranes and transplanted to the limbal area for treating corneal burns. RESULTS: Corneal stem cells had a high proliferation capacity in primary and first passage, cytokeratin 3 was not expressed in primary culture but partly in first passage. The stem cells could proliferate to form cell layer on an amniotic membrane. When transplanted, stem cells could survive on limbus. After transplantation, ocular inflammation resolved, the cornea re-epithelialized, the stromal opacity reduced, the superficial neovascularity was lessened and the conjunctival fornix re-established. CONCLUSIONS: Ocular surface conditions could be improved by allograft of corneal stem cells cultured on amniotic membranes.展开更多
基金National Key Research and Development Project of China(No.2017YFA0104101)Jiangsu Key Medical Disciplines(No.ZDXKC2016008)Technology Development Fund(No.CSE12N1701)。
文摘AIM:To explore the functions of Chordin-like 2,which is encoded by CHRDL2,in the process of retinal pigmented epithelium(RPE)differentiation and damage repair.METHODS:The fetal RPE cells(f RPE)was obtained from aborted fetus which obeyed medical ethics.Real-time quantitative polymerase chain reaction was used to measure expression quantity of CHRDL2 and other functional genes expression.Knocking down and overexpression was used to analyze the functions about Chordin-like 2.Enzyme-linked immunosorbent assay(ELISA)was used to detect the secretion of bone morphogenetic proteins 4(BMP4).Flow cytometry was used to analyze cell cycle.Cell morphology was observed by phase contrast microscope(PCM).RESULTS:In normal RPE cells,CHRDL2 was firstly upregulated and followed a downregulation but eventually,it was expressed higher than the cells which undergone epithelial-mesenchymal transition(EMT).After knocking down CHRDL2,the secretion of BMP4 was decreased,RPErelated genes(OTX2,MITF,RPE65)were downregulated while EMT-related genes(SNAI1,VIM)were upregulated.However,the expression of these related genes after overexpression of CHRDL2 had contrary results.Chordin-like 2 also regulated the cell cycle by regulating BMP pathway.When CHRDL2 was knocked down,more f RPE cells stayed in S phase of cell cycle,while adding BMP4 reduced the proportion of the cells in S phase.However,overexpression of CHRDL2 increased more BMP4 secretion,this effect decreased the number of cells in S phase,but exogenous BMP inhibitor also could change this effect.At last,in the process of RPE cells differentiation,adding BMP4 at early stage could intervene normal RPE differentiation.Compared with BMP4,inhibiting BMP pathway had no significant negative effect at early stage,but suppressed differentiation at late stage.CONCLUSION:BMP pathway can be activated in a correct temporal order,otherwise,the cells have incorrect differentiation orientation.And Chordin-like 2 plays a role in dynamic regulation of BMP pathway and it also regulates the differentiation of RPE cells.Therefore,this research enlightens a new direction to inhibit EMT and promote cell redifferentiation after injury.
文摘Cells have intrinsic mechanisms for cleaning harmful oxidants represented mainly by reactive oxygen species (ROS). Despite the antioxidant defense, ROS can cause serious damage to the retina that with age leads to various eye diseases and even blindness. Among numerous cell sites of ROS generation, mitochondrial electron transport is of crucial importance. Recently, for the purpose of cleaning ROS in the mitochondrial matrix, powerful mitochondria- targeted antioxidant “SkQ1” has been invented. We studied SkQ1 effects upon tissues of rat posterior eye cup that consisted: retinal pigment epithelium (RPE) ? choroidal coat ? scleral coat. The eye cups were isolated from the eyes of adult albino rats and cultivated in rotary tissue culture system in the presence of 20 nM SkQ1 or without this compound. After 7 days - 1 month in vitro eye cup samples were studied by immunohistochemistry, routine histology, morphometry, and digital image analysis. We have found that under chosen, “in vitro like in vivo” conditions 20 nM SkQ1 effectively reduced cell death in RPE and choroid, protected RPE from disintegration caused by cell phenotypic transformation and withdrawal from the layer, suppressed transmigration of choroidal coat cells. In the ex vivo model we used degenerative processes were more pronounced in the eye cup center where SkQ1 effect was most vivid. All this give us hopes for effectiveness of SkQ1 treatment of retinal central part that is very susceptible to light-induced over-oxidation injury and mostly suffering in many age-related diseases, AMD, in particular.
文摘Diabetic retinopathy(DR)is a common cause of blindness all over the world.Bone marrow mesenchymal stem cells(BMSCs)have been considered as a promising strategy for retinal regeneration in the treatment of DR.However,the poor viability and low levels of BMSCs engraftment limit the therapeutic potential of BMSCs.The present study aimed to examine the direct induction of BMSCs differentiation into the cell types related to retinal regeneration by using soluble cytokine ciliary neurotrophic factor(CNTF).We observed remarkably increased expression of cellular retinaldehyde-binding protein(CRALBP)and retinoid isomerohydrolase(RPE65)in BMSCs treated with CNTF in vitro,indicating the directional differentiation of BMSCs into the retinal pigment epithelium(RPE)cells,which are crucial for retinal healing.In vivo,the diabetic rat model was established by use of streptozotocin(STZ),and animals treated with BMSCs+CNTF exhibited better viability and higher delivery efficiency of the transplanted cells than those treated with BMSCs injection alone.Similar to the in-vitro result,treatment with BMSCs and CNTF combined led to the differentiation of BMSCs into beneficial cells(RPE cells),and accelerated retinal healing characterized by the activation of rod photoreceptor cells and phagocytosis function of RPE cells.In conclusion,CNTF contributes to the differentiation of BMSCs into RPE cells,which may help overcome the current stem cell therapy limitations in the field of retinal regeneration.
文摘To clarify the effects of zinc on the proliferation and apoptosis of cultured human retinal pigment epithelia (RPE) and the expression of caspase 3 in RPE cells. The effect of Zinc on theproliferation of RPE were examined with MTT method. TUNEL method was used to detect the apoptosis of RPE cells. Caspase 3 was detected by immunohistochemistry. A concentration of zinc higher than 0.001 μM could inhibit the proliferation of RPE. And the relationship between concentration of zinc higher than 10 μM and growth prohibition rate of RPE cells was dose dependent. All concentrations of zinc including 0.001 μM enhanced the expression of caspase 3 of RPE. But only the concentration of zinc higher than 0.01 μM could induce apoptosis of RPE. It is concluded that zinc could enhance the expression of caspase 3 of RPE cells and induce apoptosis of RPE cells. Caution should be taken when using zinc supplements for the treatment of ARMD patients without deficiency of zinc.
基金Supported by University of Catania,Italy,“Piano Triennale per la Ricerca 2020-2022–Grant PIACERI,project“NanoRet””.
文摘BACKGROUND Adipose-derived stem cells(ASCs)have been increasingly explored for cell-based medicine because of their numerous advantages in terms of easy availability,high proliferation rate,multipotent differentiation ability and low immunogenicity.In this respect,they have been widely investigated in the last two decades to develop therapeutic strategies for a variety of human pathologies including eye disease.In ocular diseases involving the retina,various cell types may be affected,such as Müller cells,astrocytes,photoreceptors and retinal pigment epithelium(RPE),which plays a fundamental role in the homeostasis of retinal tissue,by secreting a variety of growth factors that support retinal cells.AIM To test ASC neural differentiation using conditioned medium(CM)from an RPE cell line(ARPE-19).METHODS ASCs were isolated from adipose tissue,harvested from the subcutaneous region of healthy donors undergoing liposuction procedures.Four ASC culture conditions were investigated:ASCs cultured in basal Dulbecco's Modified Eagle Medium(DMEM);ASCs cultured in serum-free DMEM;ASCs cultured in serumfree DMEM/F12;and ASCs cultured in a CM from ARPE-19,a spontaneously arising cell line with a normal karyotype derived from a human RPE.Cell proliferation rate and viability were assessed by crystal violet and MTT assays at 1,4and 8 d of culture.At the same time points,ASC neural differentiation was evaluated by immunocytochemistry and western blot analysis for typical neuronal and glial markers:Nestin,neuronal specific enolase(NSE),protein gene product(PGP)9.5,and glial fibrillary acidic protein(GFAP).RESULTS Depending on the culture medium,ASC proliferation rate and viability showed some significant differences.Overall,less dense populations were observed in serum-free cultures,except for ASCs cultured in ARPE-19 serum-free CM.Moreover,a different cell morphology was seen in these cultures after 8 d of treatment,with more elongated cells,often showing cytoplasmic ramifications.Immunofluorescence results and western blot analysis were indicative of ASC neural differentiation.In fact,basal levels of neural markers detected under control conditions significantly increased when cells were cultured in ARPE-19 CM.Specifically,neural marker overexpression was more marked at 8 d.The most evident increase was observed for NSE and GFAP,a modest increase was observed for nestin,and less relevant changes were observed for PGP9.5.CONCLUSION The presence of growth factors produced by ARPE-19 cells in tissue culture induces ASCs to express neural differentiation markers typical of the neuronal and glial cells of the retina.
文摘OBJECTIVE: To investigate the proliferation and differentiation of cultured corneal stem cells and determine the effect of corneal stem cells cultured on amniotic membranes on the limbal area for treating corneal burns. METHODS: The proliferation and differentiation of corneal stem cells in vitro had been examined using colony-forming efficiency and immunohistochemistry. The stem cells had been cultured on amniotic membranes and transplanted to the limbal area for treating corneal burns. RESULTS: Corneal stem cells had a high proliferation capacity in primary and first passage, cytokeratin 3 was not expressed in primary culture but partly in first passage. The stem cells could proliferate to form cell layer on an amniotic membrane. When transplanted, stem cells could survive on limbus. After transplantation, ocular inflammation resolved, the cornea re-epithelialized, the stromal opacity reduced, the superficial neovascularity was lessened and the conjunctival fornix re-established. CONCLUSIONS: Ocular surface conditions could be improved by allograft of corneal stem cells cultured on amniotic membranes.
