BACKGROUND: Vascular endothelial growth factors are a family of multifunctional cytokines that can enhance vascular permeability, induce angiogenesis, promote endothelial cel growth and migration, and inhibit cel apoptosis.
OBJECTIVE:To elaborate the latest progress in the role of vascular endothelial growth factor and its receptors in the corneal tissue.
METHODS:A computer-based search of PubMed databases was performed for relevant articles published from 2005 to 2015. The key words were “vascular endothelial growth factor, cornea”. According to the inclusion and exclusion criteria, 43 articles were included in result analysis.
RESULTS AND CONCLUSION:Vascular endothelial growth factor and its receptors are involved in the regulation of corneal neovascularization by causing Tip cel activation that affects the Notch signaling pathways. Corneal lymphatic regeneration mainly relies on macrophages to secrete vascular endothelial growth factor-C or vascular endothelial growth factor-D that further activate vascular endothelial growth factor receptor-3 in the lymphatic endothelial cels to cause cel proliferation and migration, and eventualy lead to the formation of new lymphatic vessels. But herpes simplex keratitis HSK induces the corneal lymphatic regeneration by vascular endothelial growth factor-A/vascular endothelial growth factor receptor-2 pathway. Vascular endothelial growth factor family can significantly improve the damaged corneal nerve endings, epithelium and corneal sensitivity, has the function of nerve nutrition and promote restoration of the corneal epithelium.

Objective To explore the new preservation method of cornea by evaluating the structure and function of rabbit's endothelia on the condition of whole-eye preservation with aqueous removed and recipient's serum tamponaded. Methods Forty New Zealand big white rabbits (80 eyes) were random divided into two groups, 40 eyes in group A (control group) and 40 eyes in group B (experimental group). The vitality of endothelial cell on the condition of tow corneal preservation methods which were the moist chamber preservation (group A) and the whole-eye preservation with aqueous removed and recipient's serum tamponaded (group B) was compared. At the 2nd day, the 5th day, the 7th day, the 10th day, the vitality of endothelial cell was appraised through ultra-microstructure by scanning electron microscope and the trpan biuealizarin red stain. The corneal thickness was measured, and corneal endothelial cells density was calculated, and cell size was observed by image analysis system. Result In group B, the corneas remained transparent for 7 days , and the rate of vitality was 90% for7 days and that was over 80% for 10 days. In group A, the corneas remained transparent for 2 days, and the endothelial cell losing and dying were found after 5 days. Cell vitality, cell density and cell size had no statistical difference between Group B for 7 days and group A for 2 days. (all P＞0. 05). In group A, at the 5th day, the 7th day ,the 10th day, the average corneal thickness were (0.64 ± 0.04) mm, (0. 79 ± 0. 03) mm , (1.06 ± 0. 03) mm. In the group B, at the 5th day, the 7th day ,the l0th day, the average corneal thickness were (0. 55 ±0.03)mm, (0.65 ±0. 02) mm , (0. 85 ± 0. 05) mm. The average corneal thickness had significant difference between group A and group B (all P ＜ 0. 05). Conclusion Recipient serum had the function with supporting the structure and function of rabbit's corneal endothelial cell, and it could prolong the storage time with the moist chamberstorage at the same time.

Recent research found that human umbilical cord is rich in mesenchymal stem cells. These cells have the potencies of expressing many surface markers of mesenchymal stem cell and of differentiating into a variety of cells of three germ layers, synthesizing and secreting a set of trophic factors and other cytokines, and supporting the expansion and function of other cells hematopoietic stem cells and other cells. In addition, immunogenicity of these cells is realatively low.

Objective To construct Nedd4 knockout bone marrow-derived macrophages(BMDM) cell line by CRISPR/Cas9 technology and to provide an effective tool for studying the function and mechanism of Nedd4 in macrophage.Methods First,three high-grade sgRNAs targeting Nedd4 gene exons were screened using the online tool before synthesized sgRNAs were inserted into the PX330 plasmid respectively.Secondly,the recombinant plasmids were transferred into BMDM cells and monoclonal cells were obtained by limiting dilution method.The protein levels of NEDD4 in monoclonal cells were detected by Western blotting.Finally,the DNA sequence of the monoclonal cells was confirmed by sequence analysis.Results One Nedd4 knockout BMDM cell line was obtained.The sequencing result showed that the Nedd4 gene had 16bp deletion mutation in this cell line.Conclusion The Nedd4 knockout BMDM macrophage cell line constructed by CRISPR/Cas9 technology will be a useful tool for studying the function and mechanism of Nedd4 in BMDM cells.

Diabetic keratopathy (DK) is a common ocular complication of diabetes.Long-term hyperglycemia impairs many structures of the cornea, leading to corneal opacity and visual dysfunction.A large number of researches focus on the epithelium and nerve abnormities in DK, but the pathogenesis is not completely elucidated.Dendritic cells (DCs) are specialized antigen-presenting cells, linking innate and adaptive immunity, participating in the occurrence and development of diabetes and its complications.To date, there are many myths in relationship between DCs and DK to be solved, and there are a few researches that investigate the relation between DCs and the occurrence and development of diabetes.In this article, the pathogenesis and pathogenic changes of DK, the types and functions of different DCs, the relationship between DCs and chronic inflammation and delayed healing of corneal epithelium in DK, as well as the role of DCs in corneal neuropathy were reviewed in order to provide some references for further investigations about the pathogenesis and treatment of DK.

Background Diclofenac sodium eye drops,pranoprofen eye drops and bromfenac sodium hydrate eye drops are three clinical commonly used nonsteroidal anti-inflammatory drugs(NSAIDs).The variation of cytoxicity among these drugs and whether the cytoxicity is related to the supplements are also unknown.Objective This study was to compare the cytotoxicity of three non-steroidal anti-inflammatory eye drops and their active components with cultured human corneal epithelial cells (HCECs) in vitro,and to discuss toxic origins of these drugs.Methods HCECs were cultured in different drugs with the final concentration of 0.10％,0.05％,0.02％ and 0.01％.Cell proliferation was evaluated by MTT assay.Then,0.002％ eye drops (1∶50) was added,and the migration and damage of the cells were deceted by transwell migration assay and lactate dehydrogenase (LDH) assay.Results The cytotoxicity of three nonsteroidal anti-inflammatory eye drops on HCECs was concentration-dependent (all at P=0.00).Diclofenac sodium eye drops showed the most dominant effects on the proliferation,migration and damage of HCECs among the three eye drops,while bromfenac sodium eye drops showed the least effect on the cell damage (proliferation:Fdrug =20.25,P=0.00;migration:F =103.43,P =0.00;damage:Fdrug =164.16,P =0.00).Compared with the eye drops,their active components showed less cytoxicity.Pranoprofen appeared the least effects on the proliferation,migration and damage of HCECs (proliferation:Fdrug =332.27,P =0.00;migration:F =332.27,P =0.00;damage:Fdrug=154.83,P=0.00).Conclusions The cytotoxicity ofdiclofenac sodium eye drops is more obvious than that of pranoprofen eye drops or bromfenac sodium hydrate eye drops.The cytotoxicity of the three eye drops originates from their supplements or the interaction between the supplements and active components.

Background Limbal stem cells (LSCs) play an important role on the stability of corneal epithelium and corneal transparency.Rho-associated coiled-coil containing protein kinase (ROCK) inhibitor can promote cell proliferation and reduce apoptosis,such as human embryonic stem cells and karatin epithelial cells.Objective This study was to investigate the improving effect of Y-27632,a ROCK inhibitor,on the activity of rabbit LSCs in corneal preservation medium.Methods Corneal preservation solution was prepared by adding 12.5％ chondroitin sulfate,10.0％ low molecular dextran,20.0 mg/L dexamethasone,100 mg/L tobramycin sulfate,9.5 g/L Hepes and 0.375 mg/L L-glutamine in MEM.The corneas of New Zealand white rabbits were collected and preserved in the corneal preservation solution with or without Y-27632 for 4,7,14 days,and the density and morphology of corneal endothelial cells were examined by using 0.25％ trypan blue staining and 0.2％ alizarin red staining.Isolated corneal epithelial cells were seeded on 3T3 feeder layer and cultured for 7-10 days until colonies formation.Colony shape of LSCs was observed under the light microscope,and colony-formation efficiency was analyzed after Giemsa staining by Image J software.Results The morphology and density of corneal endothelial cells were normal in the corneal preservation solution with and without Y-27632 for 4 days.In the seventh day after preservation,the cells remained the regular hexagon in shape in the preservation solution with Y-27632,however,the cellular membrane was slightly shrinking with the positive staining for alizarin red in the preservation solution without Y-27632.The density of corneal endothelial cells in the corneal preservation solution without Y-27632 was (2 262-± 75) cells /mm2,while in the preservation solution with Y-27632 was (2 425 ±95) cells/mm2(P＜0.001).The cloning spheres of LSCs were similar in preservation solution both with and without Y-27632 in the freshly isolated cornea or preserved corneas and exhibited more cells inside.But in 7 days and 14 days after preservation,the cloning spheres were much smaller in the preservation solution without Y-27632 group than those in the preservation with Y-27632 group.No significant differences were found in the cloning-formation rate and survival rate of corneal epithelial cells in corneas freshly isolated or preserved for 4 days in both groups (all at P＞0.05).In 7 days and 14 days after preservation,the active rates of corneal epitheli.al cells were (73.00±2.12)％ and (56.00±0.71)％ in the preservation solution with Y27632,which were significantly higher than (66.00 ± 4.00) ％ and (49.00 ± 0.71) ％ in the preservation solution without Y-27632,showing statistically significant differences between them (t =3.098,P =0.018;t =9.798,P =0.000).In addition,the cloning-formation rates of LSCs were (11.05±0.21)％ and (3.10±1.97)％ in the preservation solution with Y-27632 in 7 days and 14 days after preservation,revealing significantly elevation in comparison with (2.05 ± 1.20) ％ and (0.40 ±0.14) ％ in the preservation solution without Y-27632 (t =18.107,P =0.000;t=3.184,P=0.017).Conclusions Y-27632 promotes the vitality and cloning-formation ability of LSCs in corneal preservation medium,suggesting its potential use during storage of cornea.

Background Interleukin-6 (IL-6) is a pleiotropic cytokine involving in inflammation and wound healing.Previous report found that IL-6 increases phosphorylated STAT3 (p-STAT3) level and promotes corneal epithelial wound healing by stimulating migration.However,the essential role of IL-6 in corneal epithelial wound healing and the expression changes in diabetic mellitus remains unknown.Objective This study was to explore the roles of IL-6 in corneal epithelial proliferation and wound healing in both normal and diabetic mice.Methods Fifty-two normal C57BL/6 mice were randomized into normal control group (32 mice) and diabetic group (20 mice).Type 1 diabetic mellitus was induced by intraperitoneal injections of 50 mg/kg streptozotocin once per day for consecutive 5 days in the mice of the diabetic group.Whole corneal epithelium was scraped in all mice,and the corneal epithelial defect area was examined by fluorescein staining in 24,48 and 72 hours after corneal epithelium removal.Recombinant mouse IL-6 or anti-IL-6 blocking antibody of 5 μl were subconjunctivally injected according to the grouping and contrasted with PBS injection group or isotype control antibody group,respectively.TKE2 cells,a mouse corneal epithelial stem/progenitor cell line,were trypsinized and incubated in the KSFM with different concentrations of IL-6 or without IL-6,and colony formation efficency (CFE) was examined by crystal violet staining.The expressions of △NP63 and Ki67,specific makers of stem cells,were detected by immunofluorescine technology.The expressions of △NP63,Ki67 and p-STAT3 proteins were assayed in the cells by Western blot,respectively.The expression of IL-6 mRNA and protein in the regenerated corneal epithelium was detected by real time quantitative PCR and ELISA.The use and care of the mice complied with the Statement of Association for Research in Vision and Ophthalmology.Results The percentage of residual corneal epithelium defect area with initial detect area was gradually shrinked over time after PBS and IL-6 injection in both normal control mice and diabetic mice,and the percentage of residual corneal epithelium defect area was significantly reduced in the IL-6 injected group compared with the PBS injected group (normal control group:Fgroup =19.982,P ＜ 0.01;Ftime =589.350,P ＜ 0.01;Diabetic group:Fgroup =25.411,P＜0.01;Ftime =334.807,P＜0.01).The CFE was (13.23± 1.12)％,(15.87± 1.30)％,(21.69±1.62)％,(25.33±1.28)％ and (18.67±1.54)％ in the blank control group and 10,20,50,100 ng/ml IL-6-treated groups,respectively,showing a gradual increase of CFE dependent upon IL-6 concetrations (F =35.547,P＜0.01).The expressions of △NP63,Ki67,p-STAT3 proteins in the cells were gradually increased over time after 50 ng/ml IL-6 treated for 5,10,15,30 and 60 minutes,and the relative expression level of the cytokines was significnatly higher in the IL-6 cultured groups than that without IL-6 culture group (all at P＜0.05).The relative expression of IL-6 mRNA in the regenerated corneal epithelilum was 0.45±0.21 and 1.00±0.16 in the diabetic group and normal control group,respectively,and compared with the normal control group,the expression of IL-6 mRNA reduced by 56％ (t=3.42,P=0.03).The content of IL-6 protein in regenerated corneal epithelium of the diabetic group was (257±12) ng/μl,which was significantly lower than (323 ± 17) ng/μl of the normal control group (t =5.60,P＜0.01).Conclusions IL-6 promotes the proliferation and regeneration of corneal limbal stem cells to repair defected corneal epithelium by activating STAT3 signaling pathway in both normal and diabetic mice,while the blocking of endogenous IL-6 impairs the corneal epithelial cell activation and wound healing.

Objective To study the expression of Notch3 in pancreatic ductal adenocarcinoma (PDAC) and to find out its relationship with clinical features and overall survival in patients with pancreatic ductal adenocarcinoma.Methods PDAC and adjacent non-cancerous tissues from 80 patients who under went surgery for primary PDAC in the Affiliated Tumor Hospital of Zhengzhou University were collected between 2008 and 2015.The specimens were divided into two subgroups by immunohistochemical staining of Notch3:the low expression group (0-4 points) and the high expression group (5-12 points).Correlations between expression of Notch3 with clinical features and prognosis of patients with PDAC were analyzed.Results A high expression of Notch3 gene was significantly associated with tumor grade,metastasis,venous invasion and TNM staging.Univariate Cox regression analysis showed that metastasis,venous invasion,TNM stage and protein expression of Notch3 were strongly correlated with overall survival of patients.Multivariate analysis showed that metastasis,TNM stage and Notch3 were independent risk factors of overall survival in patients with PDAC.Kaplan-Meier survival curves indicated that a high expression of Notch3 was an important risk factor of poor survival.Conclusions A high expression of Notch3 was significantly associated with progression and poor prognosis of PDCA.Notch3 may serve as a new indicator of PDAC progression and patient survival outcomes.

Objective To investigate the effect of miR-10b on migration and invasion of human hepatocellular carcinoma (HCC) cell lines.Methods Transwell assay was used to evaluate the motility and invasiveness in different HCC cell lines,qRT-PCR was then used to detect the expression levels of miR-10b in different HCC cell lines.Artificial mimics of miR-10b were transiently transfected into HepG2 cells,which have low expression of miR-10b,and then the changes in migration and invasion were evaluated by Transwell assay.Antagomirs of miR-10b (miR-10b-AS) were transiently transfected into MHCC97H cells,which have high expression of miR-10b,and then the changes in migration and invasion were evaluated as well.Cell morphology changes were detected by immunofluorescence and electron microscopy,Results There was a significant correlation of miR-10b expression level with cell motility and invasiveness.Low-level expression of miR-10b was observed in HepG2 cells,which exhibited weak motility and invasiveness; whereas high-level expression of miR-10b was observed in MHCC97H cells,which exhibited strong motility and invasiveness.Up-regulation of miR-10b expression in HepG2 cells increased cell motility and invasiveness,whereas inhibition of miR-10b reduced cell motility and invasiveness in MHCC97H cells.Immunofluorescence and electron microscopy results showed that up-regulation of miR-10b in HepG2 cells significantly increased proliferation of filopodia and lamellipodia,whereas inhibition of miR-10b decreased filopodia and lamellipodia amount in MHCC97H cells.Conclusion miR-10b is involved in the invasion and metastasis of HCC cell through regulation of cytoskeleton in vitro and inhibition of miR-10b is likely to be a new molecular target to block metastasis.