The expression of cytokines in aqueous humor of high myopic patients with cataracts.

Purpose: To analyze the expression of 440 human cytokines in aqueous humor of high myopic patients with cataracts. Methods: Eighty-five patients with cataracts were recruited in this study. In the screening stage, the RayBio G-Series Human Cytokine Antibody Array 440 was used to assay the aqueous humor samples collected from nine high myopic patients with cataracts and eight non-myopic patients with cataracts right before the surgery. The array was further used for verification of the screened cytokines, with aqueous humor samples obtained from 34 eyes of high myopic patients with cataracts and 34 eyes of non-myopic patients with cataracts. Results: Compared with the non-myopic patients with cataracts, the expression levels of decorin, receptor activator of NF-kB (RANK), angiopoietin-1 (ANG-1), C-X-C motif ligand 16 (CXCL16), ß-inducible gene-h3 (bIG-H3), insulin-like growth factor-binding protein 2 (IGFBP-2), and interleukin-17B (IL-17B) were statistically significantly higher in high myopic patients with cataracts (all p<0.000114). The matrix metalloproteinase-2 (MMP-2) level also increased in the aqueous humor of high myopic patients with cataracts (p = 0.0034). The concentrations of ANG-1 and MMP-2 were also increased in the aqueous humor of the confirmatory stage (all p<0.05). Conclusions: In this study, numerous cytokines in aqueous humor were detected in high myopic patients with cataracts and non-myopic patients with cataracts, and it was confirmed that the MMP-2 level in the aqueous humor of patients with high myopia was statistically significantly increased. Further verification also revealed the elevation of ANG-1 in the aqueous humor of high myopic patients with cataracts, which suggests that ANG-1 may be related to the pathogenesis of high myopia.

Nrf2 protects human lens epithelial cells against H2O2-induced oxidative and ER stress: The ATF4 may be involved.

Our previous study has shown heme oxygenase-1 (HO-1) protects human lens epithelial cells (LECs) against H2O2-induced oxidative stress and apoptosis. Nrf2, the major regulator of HO-1, is triggered during the mutual induction of oxidative stress and ER stress. In response to ER stress, unfolded protein response (UPR) serves as a program of transcriptional and translational regulation mechanism with PERK involved. Both Nrf2 and ATF4 are activated as the downstream effect of PERK signaling coordinating the convergence of dual stresses. However, the ways in which Nrf2 interacting with ATF4 regulates deteriorated redox state have not yet been fully explored. Here, the transfected LECs with Nrf2 overexpression illustrated enhanced resistance in morphology and viability upon H2O2 treatment condition. Intracellular ROS accumulation arouses ER stress, initiating PERK dependent UPR and inducing the downstream signal Nrf2 and ATF4 auto-phosphorylation. Further, converging at target promoters, ATF4 facilitates Nrf2 with the expression of ARE-dependent phase II antioxidant and detoxification enzymes. According to either Nrf2 or ATF4 gene modification, our data suggests a novel interaction between Nrf2 and ATF4 under oxidative and ER stress, thus drives specific enzymatic and non-enzymatic reactions of antioxidant mechanisms maintaining redox homeostasis. Therapies that restoring Nrf2 or ATF4 expression might help to postpone LECs aging and age-related cataract formation.

Efficacy comparison between manual small incision cataract surgery and phacoemulsification in cataract patients: a meta-analysis.

OBJECTIVE: Systematic review of manual small incision cataract surgery (MSICS) and phacoemulsification (PHACO) on the postoperative visual quality and surgical complications. METHODS: Relevant literatures on clinical efficacy of PHACO and MSICS were included by retrieving in Medline, PubMed, Chinese Biomedical Literature Database (CBM) and Chinese Academic Journal (CNKI) databases. Meta-analysis was conducted by RevMan5.0 software with OR and its 95% CI for the effect size. RESULTS: A total of ten documents were included in the study. Uncorrected visual acuity 1 week after surgery (OR = 0.84, 95% CI: 0.67 ~ 1.06, P=0.15), post-operative capsular rupture (OR = 1.07, 95% CI: 0.73~1.58, P=0.72), and corneal edema (OR = 0.90, 95% CI: 0.70~1.16, P=0.42) between MSICS and PHACO showed no statistical difference (P > 0.05). CONCLUSION: Clinical efficacy and complications of MSICS was similar tothat of PHACO.

IL-33 is induced by amyloid-ß stimulation and regulates inflammatory cytokine production in retinal pigment epithelium cells.

Age-related macular degeneration (AMD) is the predominant cause of irreversible blindness in the elderly population. Despite intensive basic and clinical research, its pathogenesis remains unclear. However, evidence suggests that immunological and inflammatory factors contribute to the pathogenesis of AMD. A newly identified cytokine, IL-33, appears to be an important pro-inflammatory cytokine promoting tissue inflammation. In this study, IL-33 was increased through amyloid-beta(1-40) (Aß(1-40)) stimulation and regulated inflammatory cytokines including IL-6, IL-8, IL-1ß, and TNF-α secretion using different signaling pathways in retinal pigment epithelium (RPE) cells. Furthermore, ST2L, the important component of the IL-33 receptor, was significantly increased following recombinant human IL-33 stimulation in RPE cells. These findings suggest that IL-33-mediated inflammatory responses in RPE cells are involved in the pathogenesis of AMD. Greater understanding of the inflammatory effect of IL-33 and its role in RPE cells should aid the development of future clinical therapeutics and enable novel pharmacological approaches towards the prevention of AMD.

[Protective effects of puerarin on lens epithelial cells in rat diabetic cataract].

OBJECTIVE: The therapeutic effects of general and local applications of puerarin in the treatment of streptozotocin (STZ)-induced rat diabetic model were compared. METHODS: Experimental research. We equally divided normal Sprague-Dawley (SD) rats into a STZ group, a peritoneal injection group, a peribulbar injection group and a control group. STZ, peritoneal injection and peribulbar injection groups were first treated with STZ. Subsequently, the STZ group was injected with normal saline intraperitoneally, while in the later two groups puerarin was injected through peritoneal and peribular routes, respectively. Control group only received peritoneal injection of saline. The morphology of lens epithelial cells (LEC) and their subcellular structure were examined by bright-field microscopy, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) 20, 40 and 60 days after the injection. Nitrogen oxide (NO) and nitric oxide synthase (NOS) were measured by biochemistry methods. Finally, inducible nitric oxide synthase (iNOS) protein and mRNA levels were monitored by Western blot and RT-PCR, respectively. Data was processed with two factorial experiment analysis of variance. RESULTS: Twenty to sixty days after the injection, marked or complete lens opacities appeared in the STZ group, whereas only slight opacities appeared in the lens in peritoneal and peribulbar puerarin groups and the lens in the control group remained clear. At the 20th, 40th and 60th day after the injection, optical microscope detected pathological changes of LEC in the STZ group. The cell volume was decreased with a dense nucleus and many bubbles appeared around the equator area. Under TEM, enlargement of cell gap, vacuoles in the cytoplasm, swelling of mitochondria and unclear structure of rough endoplasmic reticulum appeared in the LEC of the STZ group. Part of the nucleus was in karyopyknosis and peripheral nucleus gap was enlargement. Under SEM, normal fiber conjunction structure of the lens disappeared, fibers were swelling, part of fiber membranes were discontinuous, detached, and accumulated in certain areas. Mild lens opacities detected by bright-field microscope were developed in peritoneal and peribulbar puerarin injection groups. Nucleus and fibers in the lens cells of both groups appeared to be normal, with minor swelling of mitochondria, minor enlargement of endoplasmic reticulum and slight increase of intracellular space. NO, NOS and iNOS protein and mRNA of the lens were increased and up-regulated in STZ group. In the other two groups only minor changes were present and the changes were significantly less than that of the STZ group but greater than that in the control group. CONCLUSION: Peritoneal and peribulbar injection of puerarin have similar therapeutic effects in the treatment of rat diabetic cataract.

[Alternative splicing of vascular endothelial growth factor A and ocular neovascularization].

Ocular neovascularization is the primary cause of blindness in a wide range of ocular diseases. The vascular endothelial growth factor A (VEGF-A) is the key factor involved in ocular angiogenesis, which can cause eye diseases through the development of pathological angiogenesis and increase of vascular permeability. There are two families of VEGF-A isoforms formed by alternative splicing, the angiogenic VEGF-A family (VEGF(xxx)), known to contribute to ocular neovascularization, and the anti-angiogenic VEGF-A family (VEGF(xxx)b), which is found in normal ocular tissues but downregulated in human diabetic retinopathy. The first member of the VEGF(xxx)b family to be isolated was VEGF(165)b. It can significantly reduce preretinal neovascularization without inhibition of physiological intraretinal angiogenesis. As the studies on the VEGF(xxx)b family proceed more deeply, controlling the balance of VEGF(xxx) to VEGF(xxx)b isoforms may be therapeutically valuable in the treatment of angiogenic eye diseases such as diabetic retinopathy and age-related macular degeneration.

Toxicity of endogenous peroxynitrite and effects of puerarin on transplanted retinal pigment epithelial sheets in the subretinal space in mice.

AIM: To evaluate the toxicity of endogeneous peroxynitrite on transplanted retinal pigment epithelial (RPE) sheets and the effect of puerarin on their survival in the C57BL/6 mice after RPE sheets have been transplanted into SD rats' subretinal space . METHODS: C57BL/6 mice eyes were used to culture RPE cells. Ninety-six SD rats were involved in the experiment. They were divided into control (block control), streptozotocin (STZ, negative control), untransplanted RPE (positive control) and transplanted RPE groups respectively. Diabetes was induced in SD rats by intra-peritoneal STZ injection in the latter three groups. Saline was injected into the subretinal space of 24 SD rats in the untransplanted RPE group and primary RPE sheets were injected into the subretinal space of 24 SD rats in the transplanted RPE group. Puerarin (45mg/kg) was administrated into both untransplanted RPE and transplanted RPE groups of diabetic rats through intra-peritoneal injection route after RPE sheets transplantation. At 20, 40, 60 days after surgery, Western blotting analysis, DNA ladder and RT-PCR were used for determining the differences in expression of nitrotyrosine (NT, the foot print of peroxynitrite ), apoptosis and iNOS mRNA in the control, STZ, untransplanted RPE and transplanted RPE groups respectively. HE staining was used for determining the RPE survival in the subretinal space of the transplanted RPE group. RESULTS: Apoptosis and expression of NT and iNOS mRNA were observed in STZ, untransplanted RPE and transplanted RPE groups, but were delayed in untransplanted RPE and transplanted RPE groups in a time-dependent manner compared with control and STZ groups (P<0.01). There were no differences between the two groups (P>0.01). NT, DNA ladder, iNOS mRNA were down-regulated, which were associated with the decrease of expression of peroxynitrite. Numerous pigmented cells emerged and increased in number in the subretinal space during the 60-day observation period after transplantation. On day 20, heavily pigmented cells were visible at the transplant site; On day 40, monolayer and multilayered transplant was visible in the subretinal space; On day 60, heavily pigmented monolayer and multilayered transplants with round apical profile were present along Bruch's membrane. CONCLUSION: Puerarin increased the 60-day survival of C57BL/6 mice RPE xenografts in the SD rats' subretinal space, which may be related to its direct inhibition of apoptosis of RPE cells and antagnism of damage of peroxynitrite to RPE cells.

[Several notable problems in current development of cataract surgery].

The technologies about cataract surgery and intraocular lens has been developing expeditiously. However, some problems have been occurring and should be corrected. Cataract blindness can not restore the sight after surgery has been performed still existed. Some new technologies blindly introduced and applied. The comprehension about individualized selection of intraocular lens still has some bias. To solve the above problems and to hold rhythm of popularizing new techniques and to stick the key points of the technologies may healthily promote and advance the cataract surgery in China.

[MicroRNA and progresses in the region of ophthalmology].

MicroRNAs (miRNAs) consist of a growing class of short non-coding RNAs (ncRNAs) that negatively regulate the expression of genes involved in development, differentiation, proliferation, apoptosis and other important cellular processes. They regulate gene expression at the post-transcriptional level by either degradation or translational repression of a target mRNA. Nowadays more than 400 miRNAs have been identified in the human genome. A growing number of reports have established a link between a specific group of microRNAs and tissues in eyes, including cornea, len, retina. Here, we describe our current understanding of the structure, biogenesis and function of MicroRNAs, as well as their potential as novel therapeutic approaches in eye disease.

[To guard against mistakes in selection of intraocular lenses].

Development of different kinds of new intraocular lenses (IOL) provide more selections to meet various clinical requirements, which may plays an active role in making cataract surgery more perfectible. But there are many misunderstandings about how to select the proper IOL. For example, "the expensive one is the best one", "new product is absolutely perfect", and so on. Some surgeons prefer more practice and ignore the summary of the experiences. Someone unilaterally exaggerates some special function of IOL When selecting the IOL, it is a common challenge for us to fully consider the patients needs, and properly manage the relationship between the basic need and special need, and to avoid fanaticism, and provide the best benefits to the patients.

[The effect of puerarin on prevention of oxidative damage of cultured lens capsule epithelial cells].

OBJECTIVE: To investigate the peroxynitrite damage to the lens epithelial cells (LEC) and the prevention of this damage by puerarin in vitro. METHODS: This paper was experimental study. Rabbit LEC were isolated and cultured and the third or forth passage LEC were used in this experiment The experiment groups included: (1) CONTROL GROUP: Heat-pathogen free saline (NS) 200 microl was added to the medium; (2) ONOO- group: ONOO- 200 microl was added to obtain the terminal concentration at 0. 5 mmol/L; (3) Puerarin group: 5 microg/ml ONOO- and 10 microg/ml puerarin were added simultaneously. Then, the cells were cultured and collected after 6,12 or 24 hours. The nitrotyrosine (NT), a symbol of the ONOO-, was tested with immunofluorescence technique. The expression of NT protein was examined with Western blot method. The cell morphology was observed with light microscope. Cell apoptosis was examined via DNA ladder, flow cytometry and Fas/FasL immunohistochemical staining. These datas were analyzed by one-way-ANOVA and q test. RESULTS: During the 6 to 24 hours of experiment period, green color could be observed in the cell nucleus and cytoplasm of control group. Staining ranged from yellow to brown-yellow, then to brown color were observed in STZ group. Staining ranged from faint green to yellow green or faint green color were observed in puerarin group. Slight expression of nitrotyrosine (NT) could be seen in the control group. A moderate to strong expression of NT was observed at different stages in the STZ group (A = 77.22 +/- 2.44, 145.00 +/- 3.94, 235. 8 +/- 5.97). At 6 hours, a slight expression of NT could be seen in the control group (A = 72.78 +/- 2.64), this increased at 12 hours (A =89. 94 +/- 3.01) and decreased at 24 hours (A = 74. 44 +/- 3.00). With computer photo-analysis, there were significant differences between the control, STZ and puerarin groups at different period during the experiment (q = 78.12, 82.76, 69.98, P <0. 01). In the control group, cell morphology and gene DNA ladder were normal, minor apoptosis could be observed but no expression of Fas/FasL in the membrane and cytoplasm of the cells. Distinctive cell morphology changes and the typical "ladder bands" as well as the expression of Fas/FasL could be observed in STZ group. All of these aspects were comparatively normal in puerarin group. CONCLUSIONS: The LEC apoptosis induced by ONOO- in vitro could be alleviated by puerarin. Fas/FasL cell signal transduction pathway may affect and strengthen the apoptosis process mediated by ONOO-.

[To recognize monovision correctly and matching different types of intraocular lenses in two eyes].

The production of different kinds of novel intraocular lens (IOLs) with various functions plays an active role in improving cataract surgery by providing more choices to meet different clinical demands. However, each type of IOL has its own advantages and disadvantages. Therefore, it is important to implant two different kinds of IOLs into two eyes of a patient, which can optimize the advantages of these two IOLs and can obtain a better mixing vision. But there are many misunderstandings about how to comprehend the principle of monovision and matching two different types of IOLs. When we consider monovision and matching two different types of IOLs, there are many challenges for us, e.g. to explain to the patients about the difference between expected and practical results, and the psychological adaptation requires a long period; and we should to avoid selection the IOLs blindly and to provide the best results and benefits for the patients.

[Research advances of proteome on ophthalmology].

The investigation of proteome can not only show the rules of vital movement, but also play an important role to illuminate the mechanism of genesis and development on certain diseases and that may find a new way to treat those. Using the compare analysis of proteome of physiology and pathology of individual, we can find the specific protein molecule of those diseases, provide identification markers of the diseases for early diagnosis, and point out the molecule target of the new drugs. Here we reviewed the applications of proteomic in the field of ophthalmologic research.

Puerarin decreases lens epithelium cell apoptosis induced partly by peroxynitrite in diabetic rats.

The present study was designed to observe if puerarin decreases lens epithelium cell (LEC) apoptosis induced partly by peroxynitrite (ONOO(-)). One hundred and eight rats were randomly divided into control group (n=36), streptozotocin (STZ) group (n=36) and STZ + puerarin group (n=36). The rats in the control group intraperitoneally (i.p.) received 0.5 ml of saline. The rats in STZ group and STZ + puerarin group received intraperitoneal injection of STZ (45 mg/kg). Three days later, the rats in STZ + puerarin group were given puerarin (140 mg/kg per day, i.p.). On days 20, 40 and 60 of the experiment, morphologic changes of lenses were observed with slit lamp. Then the animals were sacrificed for further analysis. The amount and percentage of apoptotic LECs were determined by flow cytometry. Nitrotyrosine (NT, the foot print of ONOO(-)) was examined by immunohistochemistry. Apoptosis-related genes (iNOS, etc.) were analyzed by gene array. The results showed that in the control group, all the lenses were clear. In STZ group, gradually severe opacity of the lens was observed on days 20, 40 and 60. But in STZ + puerarin group, mild opacity of the lens was observed on day 20 and more severe on day 40, but markedly decreased on day 60. In the control group, mild apoptosis of LECs was observed. In STZ group, time-dependent increase in apoptosis of LECs was observed. In STZ + puerarin group, mild apoptosis of LECs was observed on day 20, significantly increased on day 40, but markedly decreased on day 60. There was no expression of NT in the lens in the control group, but an increased expression of NT in STZ group. In STZ + puerarin group, mild expression of NT was observed on day 20, significantly increased on day 40, but markedly decreased on day 60. There was no expression of iNOS in the lens in the control group, but continuous up-regulation of iNOS expression in STZ group. In STZ + puerarin group, mild expression of iNOS was observed on day 20, significantly increased on day 40, but markedly decreased on day 60. Except the changes of iNOS related to NO production, the other apoptosis-related genes, including BCL-2 and SOD were down-regulated, while NF-kappaB and TNFR1-FADD-caspase signal transduction way were up-regulated in STZ group. The results were opposite in STZ + puerarin group and the control group. These findings show that NT is expressed in diabetic rat lens, which proves that LEC apoptosis in diabetic lens is partly induced by ONOO(-) which may be a new oxidative damage way to form cataract. Puerarin partly decreases LEC apoptosis induced by ONOO(-) and is a potential medicine for therapy of diabetic cataract. The mechanism of puerarin dealing with diabetic cataract may be related to its direct inhibition of LEC apoptosis and antagonism of ONOO(-) in diabetic rats.

[Recent advances of cataract surgery and intraocular lens studies].

Recent advances of cataract surgery and intraocular lens (IOL) studies are reviewed briefly. This article reviews the progress in cataract surgery (technique, instruments and equipments), intraocular refractive surgery, IOL, the advantages and the disadvantages of various new techniques in the last 5 years. The importance of establishment of a patient selection criteria and a standard procedure are important for the development of a new intervention. New technology in the field of ophthalmology should be developed actively and carefully.

[Outline of benefit and disadvantage on intraocular refractive surgery].

The history, classification and current applications of intraocular refractive surgery (IRS) are expatiated. This review emphasizes the importance of the advantages and the disadvantages of IRS and patients selection criteria. Advices is brought forward to advance healthful expansion of IRS.

[Expression of vascular endothelial growth factor and its receptor in experimental choroidal neovascularization in rat].

OBJECTIVE: To study the expressions of vascular endothelial growth factor and its receptor FLK1 in krypton laser-induced choroidal neovascularization (CNV) in Brown Norway rat. METHODS: Thirty anesthetized male Brown Norway rats received krypton laser (647 nm, 360 mW, 50 micro m, 0.05 s) to induce CNV. Fundus fluorescein angiography examinations were performed just before euthanasia on days 3, 7, 14, 21, 28 and 56 after laser photocoagulation. The retina was processed for histopathology analysis. VEGF mRNA, VEGF and FLK1 expressions were demonstrated using in situ hybridization and immunohistochemistry staining respectively. RESULTS: VEGF mRNA expression was mainly observed in the vascular endothelial cells, the ganglion cells, the inner nuclear layers, the retinal pigment epithelial cells in normal retina and the vascular endothelial cells of normal choroid of BN rat. VEGF mRNA expressed in the vascular endothelial cells, the ganglion cells, the inner nuclear layers, lesion of outer nuclear layers in retina on days 3 after photocoagulation, but CNV wasn't detected. The level of VEGF mRNA expression in retina was decreased after 3 days (P < 0.01). CNV was firstly observed on day 7 after photocoagulation by FFA and histopathology. The area and density of positively stained cells for VEGF mRNA in CNV were increased during the development of CNV (P < 0.01) and no significant change after days 21 (P > 0.05). FLK1 was detected in the vascular endothelial cells, the ganglion cells of normal retina and the vascular endothelial cells of choroid. The staining of FLK1 was positive in laser induced CNV after days 7, the level of the receptor expression was increased during the development of CNV (P < 0.01) and was not significantly changed after days 21 (P > 0.05). CONCLUSIONS: VEGF and its receptor FLK1 accumulation and combination in the lesion of retina and choroid are related to choroidal neovascularization induced by laser.