ABSTRACT
Objective To evaluate the effects and underlying mechanisms of crocin on glutamate-induced apoptosis of retinal ganglion cells (RGCs) by affecting extracellular calcium influx.Methods Primary rat retinal ganglion cells were isolated and stimulated with glutamate at concentrations of 0.1 mmol/L and 1 mmol/L for 24 h or 48 h,respectively,to establish apoptosis model of RGCs.Afterwards,crocin of different doses (0.1,1.0 and 3.0 μmol/L) was used to treat the glutamate-induced RGCs for 12 h;then cell apoptosis was detected by Annexin V-FITC/PI staining.The intracellular calcium concentration was determined by FIuo-3/AM fluorescent labeling.Western blot was used to examine the effect of crocin on Ca2+-mediated apoptotic signal molecules calpain and CaMKII.The mitochondrial membrane potential was detected by JC-1 staining and mitochondrial apoptosis-related signaling molecules Caspase-3,Caspase-9 and Bcl-2/Bax were evaluated by Western blot,respectively.Results In comparison with the untreated controls,the cell apoptosis of RGCs exposed to 0.1 mmol/L of glutamate for 24 h did not significantly change (P＞ 0.05).However,apoptosis rate of the cells reached (43.050 ± 2.616) ％ when the stimulation time lasted for 48 h and showed a significant increase (P＜0.01).Treatment with higher-dose glutamate (1 mmol/L) significantly increased apoptosis of RGCs at 24 h (46.450±1.061)％ and 48 h (45.500±3.253)％ compared with the controls (P＜0.01).RGCs were induced by 1 mmol/L of glutamate for 12 h,followed by the treatment with crocin at concentrations of 0.1,1.0 and 3.0 μmol/L,respectively.Each dose of crocin could significantly inhibit cell apoptosis in the dose-dependent manner (P＜0.01).In addition,crocin at 1.0 μmol/L blocked glutamate-induced extracellular calcium influx,inhibited the expression of calcium-dependent proteins Calpainl and CaMK Ⅱ.Moreover,crocin at the dose of 1.0 μmol/L also increased mitochondrial membrane potential,suppressed the expressions of Caspase-3 and Caspase-9,and elevated Bcl-2/Bax ratio.Cornclusion Crocin inhibits glutamate-induced apoptosis of retinal ganglion cells through suppressing extracellular calcium influx,thereby blocking calcium-dependent and mitochondria-dependent apoptosis signaling pathways.
ABSTRACT
Objective:To investigate the clinical curative effect of vitreous cavity injection combined with transconjunctival sutureless vitrectomy on the patients with poliferative diabetic retinopathy.Methods:80 patients with diabetic retinopathy were enrolled in our hospital from January 2014 to January 2016,in which contained 83 sicked eyes,and randomly divided into two groups.Group A (n=40,42 sicked eyes) accepted 25G transconjunctival sutureless vitrectomy,and Group B (n=40,41 sicked eyes) adopted intravitreal injection of conbercept based on patients in Group A.The operative conditions,best-corrected visual acuity (BCV) and retinal thickness were compared between two groups,and the incidence of adverse reactions within postoperative 1 month were recorded and analyzed.Results:The operation time of group B was significantly shorter than that of group A (P＜0.05).The percentage of using electric coagulation,operative bleeding and iatrogenic fracture space in group B were significantly lower than of those group A (P＜0.05).The percentage of neovascularization vanish in group B was significantly higher than that of group A (P＜0.05).The BVCA of patients in group B in postoperative 1 month and 3 month were higher than those of group A (P＜0.05).And the thickness of retinal in group B were significantly thinner than those of Group A (P＜0.05).The incidence of vitreous hemorrhage and hyphema in group B were significantly lower than those of Group A (P＜0.05).Conclusions:Vitreous cavity injection combined with transconjunctival sutureless vitrectomy improved the operative conditions and contributed to the recovery of postoperative visual acuity and retinal in the treatment of patients with poliferative diabetic retinopathy.
ABSTRACT
Background Misfolding of Myocilin protein plays an important role in the pathogenesis of primary open angle glaucoma (POAG).GRP78 can transfer the misfolded proteins out endocytoplasmic reticulum and keep the protein synthesis function of endoplasmic reticulum.However the relationship between GRP78 and Myocilin in the pathogenesis of POAG has not been elucidated.Objective This study was to investigate and analyze the coexpressions of GRP78 and Myolicin in trabecular meshwork cells (TMCs) of POAG.Methods The trabecular meshwork tissues were obtained during the surgery of POAG and healthy donor for the isolated and in vitro culture of TMCs,and the morphology of the cells was compared between POAG-derived TMCs and donor-derived TMCs.The expression of specific factors for TMCs were detected by immunochemistry.The cells were divided into normal control group,tunicamycin (Tm)-treated group and staurosporine (STS)-treated group,and the cells were cultured by regular medium,the 1 μ mol/L Tm medium or 0.1 μmol/L STS medium for 24 hours respectively.The co-expression of GRP78 and Myocilin in the cells were detected using immunofluorescence assay.This study was approved by Ethics Committee of Xi'an No.4 Hospital,and written informed consent was obtained from each patient before surgery.Results Primarily cultured cells showed the fiat star-like and irregular appearance with 3-5 processes,round nuclei,abundant cytoplasm and black engulf particles.The 3-7 generations of POAG-derived cells grew well,showing positive expressions of laminin (LN),fibronectin (FN),neuronal specific enolase (NSE) and Vimentin.Immunofluorescence assay showed positive expressions of GRP78 and Myocilin in the cells of the Tm group,STS group and normal control group,with the reddish and green fluorescence separately.Incomplete co-expression of GRP78 and Myocilin was seen in donor-derived TMCs,and complete co-expression of GRP78 and Myocilin was found in the POAG-derived TMCs in the normal control group.Complete co-expression of GRP78 and Myocilin was exhibited in both donor-and POAG-derived TMCs in the Tm group and STS group.In addition,accumulation of GRP78 protein around nucleus was seen in both donor-and POAG-derived TMCs in the Tm group.Conclusions GRP78 and Myocilin proteins are completely co-expressed in POAG-derived TMCs,inferring that GRP78 and Myocilin play an interaction role in the pathogenesis and development of POAG.GRP78 may play a cytoprotective role against the apoptosis of TMCs caused by endoplasmic reticulum stress.
ABSTRACT
Objective To investigate the effects and mechanisms of a disintegrin and metalloproteinase 17 (ADAM17) on high-glucose mediated permeability,proliferation and migration in human retinal microvascular endothelial cells (HRMECs).Methods HRMECs were divided into 4 groups:normal group (5 mmol · L-1 glucose),high glucose group (25 mmol · L-1 glucose),NC (Negative control for siRNA) + high glucose group and siADAM17 (ADAM17 siRNA) + high glucose group.The expression of ADAM17 was detected using real time PCR and Western blot.Horseradish Peroxidase (HRP) was used to detect the permeability of HRMECs.Cell Counting Kit-8 (CCK-8)and BrdU were used to evaluate cell proliferation.Cell migration was determined using Transwell assay.In addition,the expression of p-EGFR,p-ERK and MMP9 was assayed using Western blot.Results Compared with normal group,the mRNA and protein levels of ADAM17 were increased in high glucose group (P ＜ 0.01).ADAM17 expression of siADAM17 + high glucose group was markedly reduced compared with NC + high glucose group.High glucose increased the permeability of HRP comparison to normal group,whereas in siADAM17 + high glucose group the permeability of HRP was reduced compared with NC + high glucose group.The optical density of HRMECs was decreased in siADAM17 + high glucose group 1.53 ± 0.29 in comparison with NC + high glucose group 2.43 ± 0.25,as well as the content of BrdU-incorporation(P ＜ 0.05).The number of migrated cells in high glucose group,NC + high glucose group,siADAM17 + high glucose group and normal group were 157.00 ± 7.93,169.00 ± 10.12,121.00 ± 9.28,110.00 ±8.25,respectively.Moreover,the expression of p-EGFR,p-ERK and MMP9 in siADAM17 +high glucose group was decreased compared with NC + high glucose group (all P ＜0.01).Conclusion SiADAM17 can reduce the cell permeability,suppressed and migration induced by high glucose via EGFR/ERK/MMP9 signaling pathway.
ABSTRACT
Background Ocular alkali burns leads to corneal ulcer and angiogenesis and even corneal opacity.There is still no ideal treatment method.Studies showed that mesenchymal stem cells (MSCs) can repair corneal wound in vivo,but the specific mechanism is still not clear.Objective This study aimed to observe the histopathological change after the early transplatation of bone marrow MSCs (BMSCs) for corneal alkali burn model in rabbits and explore the anti-inflammatory effects of MSCs after corneal alkali burn.Methods Bone marrow of 4 ml was collected from 2-3 month-old Japanese rabbit.BMSCs were isolated and cultured from the bone marrow of rabbits,and the third generation of cells were used in this study.Cultured cells were identified by morphology and the expressions of surface markers.Corneal alkali burn models were extablished in the right eyes of 24 rabbits by attaching the filter paper with 0.1％ NaOH at the central cornea for 30 seconds,and then the models were randomized into 2 groups.BMSCs suspension of 300 μl (concentration 5×l06/μl) was subconjunctivally injected 1 hour after modeling in the BMSCs group,and equal volume of PBS was used in the same way in the PBS group.Corneal opacification was scored under the slim lamp microscope in 3,14 and 28 days after injection.The polymorphonuclear neutrophils (PMNs) were counted by histopathological examination,and the expression of matrix metalloproteinase-2 (MMP-2) in the corneal tissue was evaluated by immunochemistry in various time points.The use and care of the rabbits followed the statement of ARVO.Results The rabbit BMSCs were plastic-adherent cells that exhibited a fibroblastlike shape.Cultrued cells highly expressed surface adhesion molecular markers CD29 and CD90 (99.18％ and 97.94％) and lowly expressed hematopoietic cell markers CD34 and CD31 (0.74％ and 0.15％).Opacification of cornea,defect of corneal epithelium,stromal edema and neovascularization appeared after modeling.In 14 days and 28 days after modeling,the opacification scores in the BMSCs group were 2.37±0.52 and 2.25±0.50,which were significantly lower than 3.00±0.53 and 3.25 ±0.50 in the PBS group (t =2.376,2.828,both at P＜0.05).After subconjunctival injection,the number of PMNs was (34.17 ±1.85) /12 fields and (25.64 ±3.86)/12 fields in the BMSCs group,showing significant decrease in comparison with (42.70 ±1.54) /12 fields and (32.67 ±1.42)/12 fields in the PBS group (t=10.021,4.832,both at P=0.000).The expression levels of MMP-2 (A value) in cornea were 0.388±0.016 and 0.384±0.006 in the BMSCs group,with considerable decreases in comparison with 0.438± 0.006 and 0.412± 0.005 in the PBS group (t=10.205,13.514,both at P=0.000).Conclusions Early transplantation of BMSCs can arrest the occurrance of corneal ulcer by suppressing the infiltration of PMNs,alleviateing the inflammation reaction,downregulating the expression of MMP-2 in cornea and inhibiting the degradation of stromal collagen fibers.
ABSTRACT
<p><b>OBJECTIVE</b>To evaluate the effect of basic fibroblast growth factor (bFGF) treated collagen composite sponge on vascularization of HA orbital implants.</p><p><b>METHODS</b>New Zealand rabbits received three different orbital implants:naked implants, implants wrapped with collagen composite sponge and implants wrapped with bFGF treated collagen composite sponge.Implants were harvested 2, 4, 6, 8 and 12 weeks after surgery. The vascularization of implants was then assessed by light and electron microscopy.</p><p><b>RESULTS</b>At post-surgery weeks of 2, 4 and 6, bFGF treated collagen composite sponge induced the highest degree of vascularization of orbital implants. Collagen composite sponge alone resulted in higher extent of vascularization than naked implants. Complete vascularization of implants was observed at post-surgery 6 weeks by bFGF treated collagen composite sponge, which was not observed in the other two groups until post-surgery 8 weeks. There were significant differences in the average length of fibrovasculature and in the degree of vascularization among each group at post-surgery 2, 4 and 6 weeks (P<0.05), while no statistical difference was observed at post-surgery 8 and 12 weeks (P>0.05).</p><p><b>CONCLUSIONS</b>bFGF treated collagen composite sponge facilitates fibrovascularization of orbital implants, and shortens the time required for complete vascularization. Collagen composite sponge alone promotes early-stage fibrovascularization, but fails to facilitate complete vascularization of orbital implants.</p>
Subject(s)
Animals , Female , Male , Rabbits , Collagen , Pharmacology , Fibroblast Growth Factor 2 , Pharmacology , Neovascularization, Physiologic , Orbital ImplantsABSTRACT
Background Intraorbital implantation of coralline porous hydroxyapatite (CHA) is a favorable cosmetic method after enucleation.However,the low degree of vascularizatiou in implant results in implant infection and exposure.Studies showed that a collagen composite sponge treated by basic fibroblast growth factor (bFGF/ collagen composite sponge) can promote angiogenesis.However,whether bFGF/collagen composite sponge improves the vascularization of CHA implants is unclear.Objective This study was to investigate the accelerating effect of bFGF collagen composite sponge on vascularization of orbital implant made of CHA using 99Tcm-methylene diphosphate (MDP) scan.Methods Forty-five New Zealand rabbits were randomly assigned to 3 groups.Evisceration of eyeball was performed on the left eyes of rabbits,and naked CHA,collagen composite sponge wrapped CHA and bFGF/collagen composite sponge wrapped CHA were implanted into the orbit respectively in 3 groups.99Tcm-MDP of 3 mCi was injected in the rabbits via ear vein in 2,4,6,8 and 12 weeks,and the vascular enhancement intensity on implants was observed 3 hours after injection.The ratio of average radioactive count from the area of interest with the same size between the left eyes and the right eyes was calculated.The implants were extracted for histopathological examination in the 12 weeks.Results As the lapse of postoperative time,the inflammation response gradually disappeared and no exposure of implants was seen during the 12-week duration.A similar vascular development strength was found in the area of interest among the 3 groups 2 weeks after surgery.However,the vascular development was significantly enhanced in the left eyes compared the right eyes from 4 to 6 weeks,with the highest intensity in the 8th week in the naked CHA group and collagen composite sponge wrapped CHA group.In the bFGF/ collagen composite sponge wrapped CHA group,the strongest image was in the 6th week after operation.The ratios of average radioactive count between the left eyes and the right eyes were significantly higher in the bFGF/collagen somposite sponge wrapped CHA group compared with the naked CHA group and collagen composite sponge wrapped CHA group (all at P＜0.05),and ratios of average radioactive count of the collagen composite sponge wrapped CHA group was significantly higher than that of the naked CHA group (all at P＜0.05).New blood vessels ingrowed toward the center of the implants through the coralline porous under the optical microscope.Conclusions Both bFGF (20 μg)/collagen composite sponge and collagen composite sponge can accelerate the ingrowth of vessel in the CHA,but the promoting effect of bFGF collagen composite sponge is prominent.
ABSTRACT
Background Anti-scarring is a focus following glaucoma filtering surgery.It has been verified that expression of heat shock protein 47 (HSP47) is always correlated with that of various types of collagens and closely related with the collagen-related diseases including fibrosis in various organs.However,the relationship between the expression of HSP47 and fibrosis of filtering bleb is unclear.Ohjective Present study was to investigate the dynamic expression of HSP47 in subconjunctival filtering bleb after anti-glaucomatous filtering surgery.Methods Filtering surgery was performed on the right eyes of 10 SPF male Spargue-Dawley(SD) rats.Then the operative eyes were randomized into the postoperative 7-day group and 14-day group according to the randomized number table,and the left eyes of the rats served as the normal control group.The shape of filtering blebs and the ocular anterior segment response were examined under microscope daily.The animals were sacrificed by excessive anesthesia on day 7 and 14 after operation,respectively,and the specimens were prepared of the eyes.Regular histopathological examination was performed to observe the collagen fibrosis change,and immunohistochemistry was carried out to assay the dynamic expression of HSP47 depended on the fibrosis.Percentage of positive cells for HSP47 were calculated.The use and care of the experimental animals complied with the Regulation for the Administration of Affair Concerning the Experimental Animals by State Science and Technology Committee.Results Diffuse subconjunctival blebs were seen postoperatively in t0 eyes after surgery with mild inflammatory response in ocular anterior segment.Hematoxylin-eosin staining showed that compared with the specimens of the normal control group,fibroblasts obviously proliferated and collagenous fibers increased in the specimens of operative group.The HSP47 protein was less expressed in cytoplasm of many fibroblasts and less vascular endothelial cells in the normal rat specimens.The expressing intensity of HSP47 protein was enhanced.However,the expression intensity was weaker in the postoperative 14-day group in comparison with the 7-day group.The percentage of positive cells for HSP47 in the filtering blebs 7 days after operation was (56.40±1.12)％,that in the normal control group was (13.70±0.74)％,with a significant difference between them (P=0.000).In the postoperative 14-day group,the percentage of positive cells for HSP47 reduced from (56.40± 1.12) ％ to (23.90±0.76) ％ (P =0.000),but it was still higher than that of the normal control group (P =0.000).Conclusions Expression intensity of HSP47 alters as the activity of fibroblasts in filtering bleb,suggesting that HSP47 plays a role in collagen-fibrosis following filtering surgery in SD rats.
ABSTRACT
ObjectiveTo analyze the protective effects of heat-shock response on the retinae of the rats after retinal ischemic reperfusion injury. MethodTwenty Wistar rats (20 eyes) were divided into 4 groups: intracameral perfusion group (group P), intracameral perfusion after quercetin injection group (group P+Q), intracameral perfusion after heat shock group (group P+H), and intracameral perfusion after quercetin injection and heat shock group (group P+Q+H). According to the standard program established by International Society for Clinical Visual Electrophysiology, we recorded the results of the dark-adapted electroretinogram (D-ERG),oscillatory potentials (OPs),and light-adapted ERG (L-ERG) of the rats with intraocular hypertension after induced by heat shock response. The expressions of HSP 70 of the rats in all groups were observed by Western blotting.ResultsThe expression of HSP 70 of the rats in group P+H was the highest in all groups, but the expressions of HSP70 in group P+Q and P+Q+H were inhibited significantly. The amplitudes of a and b wave of ERG and O 2 wave of OPs decreased, and the delitescence of them were delayed significantly in rats after intracameral perfusion. The amplitude of b wave of D-ERG and O 2 wave of OPs in group P+H were higher than which in group P. Zero hour after perfusion, the amplitudes of all waves in group P+H increased significantly (P
ABSTRACT
Objective To monitor the release of amino acids of the whole retina during and after experimental glaucoma by increasing the intraocular pressure (IOP). Methods Experimental glaucoma was induced in one of the two eyes of rabbits by increasing IOP at 120 mm Hg for 45 min under infusion of saline in anterior chamber;then the pressure was released and the needle inserted into the anterior chamber was removed,this state was maintained for another 45 min.Every 15 min during the experiment 5 rabbits were killed and experimental eyes were enucleated.Aliquots (20 ?l) of the retinal extracts (see below) were mixed with ophthaldialdehyde reagent and analysed for amino acid content by the HPLC method of Wangwei, using a 150 mm?4.6 mm,5 ?m C18 column. Results A large increase in the release of glutamate,but not of the other three amino acids monitored,occurred during initial experimental ocular hypertension.It reached peak value of (111.73?17.46) 10 -5 mmol/g at 15 min of hypertension.15 min after release of intraocular pressure,again,immediately large and specific increase in the concentration of glutamate was reached to (102.96?51.91) 10 -5 mmol/g.In eyes subjected to paracentesis of anterior chamber,no difference was found between experimental eyes and controls. Conclusion These results suggest that glutamate is triggered by increasing the IOP,and it releases not only during the period of experimental ocular hypertension,but also afterwards.