ObjectiveTo explore an optimized protocol of decellularization to fabricate an ideal scaffold derived from porcine skeletal muscle acellular matrix. MethodsSerial-step protocol of homogenating-milling-detergent method was used to fabricate decellularized porcine muscle tissue (DPMT) derived from native porcine skeletal muscle tissue from adult pig waist. Histological method was used to assess the effects of decellularization and degreasing. Sirius red staining was used to analyze collagen components. Scanning electron microscopy, BCA assay, and PicoGreen assay were used to evaluate the ultrastructure, total protein content, and DNA content in DPMT. The adipose derived stem cells (ADSCs), NIH3T3 cells, and human umbilical vein endothelial cells (HUVECs) were cultured in extraction liquor of DPMT in different concentrations for 1, 3, and 5 days, then the relative growth rate was calculated with cell counting kit 8 to assess the toxicity in vitro. Live/dead cell staining was used to evaluate the cytocompatibility by seeding HUVECs on the surface of DPMT and co-cultured in vitro for 3 days. For in vivo test, DPMT was subcutaneously implanted at dorsal site of male specific-pathogen free Sprague Dawley rats and harvested after 3, 7, 14, and 28 days. Gross obersvation was done and transverse diameter of remained DPMT in vivo was determined. HE staining and immunohistochemical staining of CD31 were used to assess inflammatory response and new capillary rings formation. ResultsDecellularization of the porcine skeletal muscle tissue by homogenating-milling-detergent serial steps protocol was effective, time-saving, and simple, which could be finished within only 1 day. The decellularizarion and degreasing effect of DPMT was complete. The main component of DPMT was collagen type I and type IV. The DNA content in DPMT was (15.902±1.392) ng/mg dry weight, the total protein content was 68.94% of DPMT dry weight, which was significantly less than those of fresh skeletal muscle tissue[(140.727±10.422) ng/mg and 93.14%] (P<0.05). The microstructure of DPMT was homogeneous and porous. The result of cytocompatibility revealed that the cytotoxicity of DPMT was 0-1 grade, and HUVECs could stably grow on DPMT. In vivo study revealed DPMT could almost maintain its structural integrity at 14 days and it degraded completely at 28 days after implantation. The inflammatory response peaked at 3 days after implantation, and reduced obviously at 7 days. Difference was significant in the number of inflammatory cells between 2 time points (P<0.05). Neovascularization was observed at 7 days after implantation and the number of new vessels increased at 14 days, showing significant difference between at 7 and 14 days (P<0.05). ConclusionThe homogenating-milling-detergent serial-steps protocol is effective, time-saving, and reproducible. The DPMT reveals to be cell and lipid free, with highly preserved protein component. DPMT has good biocompatibility both in vitro and in vivo and may also have potential in promoting neovascularization.
ObjectiveTo investigate the ability of autologous peripheral blood endothelial progenitor cells (EPCs) in promoting neovascularization of tissue engineered bone and osteogenesis of bone marrow mesenchymal stem cells (BMSCs). MethodThe peripheral blood EPCs and BMSCs from No. 1-9 New Zealand rabbits were isolated, cultured, and identified. According to the cell types, the third generation of cells were divided into 3 groups:EPCs (group A), BMSCs (group B), and co-cultured cells of EPCs and BMSCs (group C, EPCs:BMSCs=1:2) . Then cells were seeded on the partially deproteinised bone (PDPB) packaged with fibronectin to construct tissue engineered bone. After 4 days, autologous heterotopic transplantation of tissue engineered bone was performed in the rabbit's muscles bag of groups A, B, and C (the right arm, left arm, right lower limb respectively, 2 pieces each part). At 2, 4, and 8 weeks after transplantation, the growth of tissue engineered bone was observed, and the rate of bone ingrowth was calculated by HE staining; the expressions of CD34, CD105, and zonula occludens protein 1(ZO-1) were compared by immunohistochemical staining at each time point in tissue engineered bone among 3 groups. ResultsThe EPCs and BMSCs were isolated and identified successfully; immunofluorescent staining showed that EPCs were positive for CD34, CD133, and von Willebrand factor (vWF), and BMSCs were positive for CD29 and CD90 and were negative for CD34. The tissue engineered bone constructed in 3 groups was transplanted successfully. At 2, 4, and 8 weeks after autologous heterotopic transplantation, the general observations showed that the soft tissue around the tissue engineered bone increased and thickened gradually in each group with time passing; the boundary between bone and soft tissue was not clear; the pore space of tissue engineered bone gradually was filled, especially in group C, the circuitous vascular network could be seen in the tissue engineered bone. HE staining showed capillaries and collagen fibers increased gradually, tissue engineered bone ingrowth rate was significantly higher in group C than groups A and B at 4 and 8 weeks (P<0.05) , and group B was significantly higher than group A (P<0.05) . Immunohistochemical staining showed that the expressions of CD34, CD105, and ZO-1 in tissue engineered bone of 3 groups all increased with the extension of time, showing significant differences between groups at each time point (P<0.05) . At 2 weeks after transplantation, the expression of CD105 in group C was significantly higher than that in groups A and B (P<0.05) ; at 4 and 8 weeks, CD34, CD105, and ZO-1 expressions showed significant differences between 2 groups (P<0.05) ; the expression was the highest in group C, and was the lowest in group B. ConclusionsAutologous peripheral blood EPCs and BMSCs have synergistic effect, and can promote neovascularization and osteogenesis of tissue engineered bone in vivo.
ObjectiveTo review the osteoclasts (OC) function beyond bone resorption. MethodsThe related literature on OC function beyond bone resorption was reviewed, analyzed, and summarized. ResultsOC control the bone formation through releasing of matrix-derived growth factors, bidirectional cell-to-cell signals, and secreting OC-coupling factors, and play an important role in the niche formation, hematopoietic stem cells mobilization, and maintenance of its quantity and function;besides, OCs also regulate angiogenesis. ConclusionThese discoveries greatly enrich the current knowledge of OC function and open up an all-new research domain. However, the exact regulatory mechanism of OC affecting the hematopoiesis is still lack in-depth understood. Additionally, it remains to be elucidated how OC-coupling factors act on osteoblast lineage differentiation and how OC-induced angiogenesis participates in physiological and pathological processes. Unclosing the underlying mechanisms will facilitate providing scientific therapeutic strategies for treatment of many OC-related diseases.
Axon guidance molecules, slit glycoprotein (Slit) and Roundabout receptors (Robo) were firstly identified in the central neural system of Drosophila melanogaster. The Slit-Robo signal plays a crucial role in axon guidance, inflammation, tumor metastasis and angiogenesis, of which the role of Slit2-Robo pathway in angiogenesis has drawn a greater attention and still remains conflicting. Herein, we provide a review on the role of Slit2-Robo pathway in ocular angiogenesis and vascularization of other organs and systems. We hope this review will be the basis of further study on the mechanism of Slit2-Robo signaling on angiogenesis and provide new target for the therapy on ocular vascular disease
The effect and opportunity of argon laser photocoagulation for the retinal neovascularization in branch retinal vein occlusion in 30 patients were investigated with a control group of 34 patients received nonlaser but routine treatment. The results of the therapeutic effect demonstrated that the neovascularization disappeared completely in 23 cases and became smaller in 7 cases after laser photocoagulation. The incidnce of vitreous hemorrhage in laser group was 43.3% before laser treatment and none after treatment in the duration of observation,and 70.6% in control group. The progression of visual acuity after treatment in laser group was much better than in control group(P＜0. 005)at the time of the latest examination. We found the therapeutic effect was relation to the area, location of the neovascularization in retina,as well as whether the new vessels protruding into vitreous or not. （Chin J Ocul Fundus Dis,1994,10:195-198）
Objective To observe the therapeutic effect of ultrasonic microbubble combined with bevacizumab (Avastin) on choroidal neovascularization induced by photocoagulation in rabbits.Methods CNV was induced by photocoagulation with argon laser in 30 rabbits (60 eyes).All of the rabbits underwent fundus fluorecein angiography (FFA) 21 days after photocoagulation; 6-8 hours later, 3 rabbits were randomly chosen to be executed to having the immunohistochemical examination.Twenty one days after photocoagulation, 27 rabbits were divided randomly into 3 groups: bevacizumb, ultrasonic microbubble + bevacizumb,and control group; each group has 9 rabbits (18 eyes).The rabbits in control group had no interference treatment; while the rats in bevacizumb and ultrasonic microbubble + bevacizumb group underwent injection with bevacizumb or ultrasonic microbubble + bevacizumb respectively.FFA was performed on all of the rabbits 7,14,and 28 days after photocoagulation to observe the inhibition of CNV; immunofluorecence and Western blot were used to detect the expression of VEGF in retina and choroid.Twentyeight days is the time point to determine the therapeutic efficacy. The expression of VEGF and the results of FFA were the sdandards of the judgement of therapeutic efficacy.Results Proliferaion of CNV to the retinal inner layer and the obvious leakage of fluoresein in the photocoagulation area indicated that the model of CNV was set up successfully. Twenty eight days after injection,obvious fluorescent leakage was found in the control group, and the average fluorescent leakage in bevacizumab group differed much from the control group（t=16.2952，Plt;0.05）; while the difference between ultrasonic microbubble + bevacizumb group and bevacizumab group was also significant (t=4.7955，Plt;0.05) . At the same time point, the expression of VEGF in bevacizumab group detected by immunofluorecent assay and Western blot differed much from the control group (t=7.0327，9.2596；Plt;0.05),and the difference of VEGF between ultrasonic microbubble + bevacizumb group and bevacizumab group was significant（t=2.9724,17.1937；Plt;0.05）. this experiment show that ultrasound combined bevacizumab intravitreal injection of the therapeutic effect of CNV superior to other groups(Plt;0.01).Conclusion Ultrasound microbubble combined with bevacizumab injection may improve the therapeutic effect on CNV by inhibiting the expression of VEGF.
Purpose To estabalish a quantifying model of retinal neovascularization suitable for the study of pathogenesis and therapeutic intervention for the retinal neovascularization． Methods Sixteen one-week-old C57BL/6 mice were exposed to 75% oxygen for 5 days and then to room air and 16 mice of the same age kept in room air as controls.Ink-perfused retinal flatmount was examined to assess the oxygen-induced changes of retinal vessels.The proliferated neovascular response was quantitated by counting the nuclei of endothelial cells of new vessels extending from the retina into the vitreous in 6 mu;m sagittal cross sections． VEGF and bFGF were determined on the cross-sections after immunohistochemcal stain. Results Constriction and closure of the blood vessels were found under the hyperoxia condition,and dilation and proliferation were found under the relatively hypoxia status.There was a mean of 24 neovascular nuclei per cross-section in the oxygen-treated retina and less than 1 nucleus in the control group (P＜0.001).VEGF stain was found ber in the inner retinal layer of oxygen-treated mouse than in that of the controls. Conclusion The quantifying model of retinal neovascularization may fascilitate the further researches of medical intervention and pathogenesis of retinal neovacularization. (Chin J Ocul Fundus Dis，2000，16：213-284)
Age-related macular degeneration (AMD) is a multifactorial disease affected by environmental factors and genetic variation, which is a major cause of irreversible vision loss in the elderly. miRNA is a kind of endogenous non-coding RNA, which plays an important role in the pathogenesis of AMD, such as oxidative stress, pathological neovascularization and inflammation, by inhibiting or silencing the expression of transcription genes. miRNA has unique advantages in terms of ease synthesis, targeting and additive effect, a large number of experiments have proved the therapeutic potential of miRNA in AMD, which is expected to become a new method for the treatment of AMD in the future. Since the pathogenesis of AMD has not been fully elucidated, it is still necessary to continue to study the pathogenesis of AMD, the biological effects and mechanisms of various miRNA in the occurrence and development of AMD, and observe its therapeutic effects in AMD, so as to provide more effective options for the precise prevention and treatment of AMD.
Objective To investigate auto-cortex of crystalline lens-induced neovascular epiretinal membrane（NVERM）by micro-injuring posterior c apsule of crystalline lens. Methods twenty four C57BL/6 mouse between 4-6 weeks were selected, and divided into two groups randomly: auto-cortex of crystalline group and the control group. The auto-cortex of crystalline group was treated by penetrating the posterior capsule of lens and washing out the lens cortex into the mouse vitreous using PBS (phosphate buffered solution), while the control group were injected PBS into vitreous merely. Clinical change s were followed by slit-lamp examination and photograph. The eye balls were enu cleated at the day of 3, 7, 14 and 28 after operation. Both HE and immunohistoch emistry were used to detect the pathological changes. Results postoperative one to three days, 11 of 12 mouse in autocortex of crystalline g roup, lens appear to alba turbid at different levels one after another, and then develop into highdensity chinaware white. Postoperative (po) three days, HE s taining shows cortex of lens debris transmigrated in vitreous cavity, and some o f which approached to internal limiting membrane and lead it to rough and discon tinue; Po7-14 days, the capillary in retina expanded, migrated and broke though t internal limiting membrane which got to the pro retina and became the new ves sels. And typical NVERM were observed. Po28 days, some vascularslike structure formed in vitreous cavity. None of mouse in control group developed NVERM. Conclusion Auto-cortex of crystalline lens can induced neovascular epiretinal membrane in C57BL/6 mouse. (Chin J Ocul Fundus Dis,2008,24:118-121)
Purpose To investigate the roles of vascular endothelial growth factor (VEGF),glutamate and gamma;- aminobutyric acid (GABA) in neovascularization of proliferative diabetic retinopathy (PDR). Methods Vitreous samples were collected from 25 patients (27 eyes)with PDR and 14 patients (14 eyes) with idiopathic macular hole.VEGF levels were determined by ELISA.Amino acids analyses were performed by high-performance liquid chromatography. Results Patients with PDR had significantly higher concentrations of VEGF (median 0.41 ng/ml,quartile 0.54 ng/ml) than controls (median 0.017 ng/ml,quartile 0.01 ng/ml)(Plt;0.001).The levels of glutamate [(11.7plusmn;3.0) mu;mol/L] and GABA [(7.2plusmn;3.9mu;mol/L)] were also higher in patients with PDR than glutamate [(5.8plusmn;0.7) mu;mol/L] and GABA [(3.3plusmn;2.9) mu;mol/L) in controls (Plt;0.05).The glutamate level and GABA level had a significantly positive correlation with VEGF level. Conclusions The increased levels of glutamate and GABA indicate retinal ischemia.The correlations of glutamate and GABA levels with an elevated VEGF level provide biochemical support for ischemi induced neovascularization in patients with PDR.The findings present novel modalities in treatment of PDR. (Chin J Ocul Fundus Dis,2000,16:162-165)