Neuroprotective effects of overexpressed microRNA-200a on activation of glaucoma-related retinal glial cells and apoptosis of ganglion cells via downregulating FGF7-mediated MAPK signaling pathway.

Glaucoma is a progressive optic neuropathy and is one of the leading causes of blindness in the industrialized countries. The involvement of microRNAs (miRs) has been implicated in regulating the complex biological responses to changes in intraocular pressure. However, the therapeutic role of miR-200a on glaucoma has not been well studied yet. In this study, we confirmed the role of miR-200a in glaucoma progression and identified the related mechanism. Microarray expression profiles were used to screen the glaucoma-related genes. The relationship between miR-200a and FGF7 was validated by bioinformatics analysis and dual-luciferase reporter gene assay. Glaucoma-related parameters including the expression of CD11b and iNOS, activation of Muller cells, and apoptosis of retinal ganglion cells (RGCs) in the mouse model were measured by immunohistochemistry, MTT assay and TUNEL assay, respectively. miR-200a was reduced in glaucoma, whereas FGF7 was robustly induced. Thereby, we speculated that FGF7 was negatively regulated by miR-200a. Downregulated miR-200a could activate the MAPK signaling pathway following elevations in ERK, JNK, p38 and Bax expression and reduction in Bcl-2 expression. In the mouse model, downregulated miR-200a increased the expression of CD11b and iNOS and the apoptosis of RGCs, but stimulated the inactivation of Muller cells. However, the above-mentioned alternations induced by downregulated miR-200a were reversed after FGF7 repression. miR-200a can inhibit the FGF7-mediated MAPK signaling pathway and play a protective role on improving the glaucoma-induced optical nerve injury.

A comparison of surgical efficacy between a 1.8-mm microincision and 3.2-mm and 5.5-mm incisions for phacoemulsification.

Phacoemulsification is a commonly used surgical method in cataract surgery. This paper observes and compares the surgical efficacy of three incisions of different length for phacoemulsification to identify the optimal method for cataract surgery. Ninety patients were enrolled in the present study and divided into three groups. The 1.8-mm group received Bausch & Lomb MI60 foldable intraocular lens (IOL) implantation (n=30), 3.2-mm group received Bausch & Lomb Akreos AO foldable lens implantation (n=30), and 5.5-mm group received Alcon TYPE 05 rigid IOL implantation (n=30). Visual acuity, Oculyzer-based anterior segment analysis, and corneal endothelial cell count before surgery, and 3, 7, 30, and 90d after surgery were recorded and compared. Pseudophakic accommodation three days, one week, one month, and three months after surgery was determined. Intraoperative ultrasound time and ultrasonic energy were recorded. It was finally concluded that for phacoemulsification with the same phaco tip, a 1.8-mm microincision can lead to quicker recovery of visual acuity, more stable astigmatism, and higher pseudophakic accommodation than conventional incision.

Comparison of three fluorescence labeling and tracking methods of endothelial progenitor cells in laser-injured retina.

AIM: To compare three kinds of fluorescent probes for in vitro labeling and in vivo tracking of endothelial progenitor cells (EPCs) in a mouse model of laser-induced retinal injury. METHODS: EPCs were isolated from human umbilical cord blood mononuclear cells and labeled with three different fluorescent probes: 5-(and-6)-carboxyfluorescein diacetate succinimidyl ester (CFSE), 1,1'-dilinoleyl-3,3,3',3'-tetramethylindo-carbocyanine perchlorate linked acetylated low-density lipoprotein (DiI-AcLDL), and green fluorescent protein (GFP). The fluorescent intensity of EPCs was examined by confocal microscopy. Survival rate of labeled EPCs was calculated with trypan blue staining, and their adhesive capability was assessed. A mouse model of retinal injury was induced by laser, and EPCs were injected into the vitreous cavity. Frozen section and fluorescein angiography on flat-mounted retinal samples was employed to track the labeled EPCs in vivo. RESULTS: EPCs labeled with CFSE and DiI-AcLDL exhibited an intense green and red fluorescence at the beginning; the fluorescence intensity decreased gradually to 20.23% and 49.99% respectively, after 28d. On the contrary, the florescent intensity of GFP-labeled EPCs increased in a time-dependent manner. All labeled EPCs showed normal morphology and no significant change in survival and adhesive capability. In the mouse model, transplantation of EPCs showed a protective effect against retinal injury. EPCs labeled with CFSE and DiI-AcLDL were successfully tracked in mice during the development of retinal injury and repair; however, GFP-labeled EPCs were not detected in the laser-injured mouse retina. CONCLUSION: The three fluorescent markers used in this study have their own set of advantages and disadvantages. CFSE and DiI-AcLDL are suitable for short-term EPC-labeling, while GFP should be used for long-term labeling. The choice of fluorescent markers should be guided by the purpose of the study.

Nonlethal Levels of Zeaxanthin Inhibit Cell Migration, Invasion, and Secretion of MMP-2 via NF-κB Pathway in Cultured Human Uveal Melanoma Cells.

Zeaxanthin at nonlethal dosages (3-10 µM) significantly inhibited the cell migration of cultured uveal melanoma cells (C918 cell line) as determined by wound healing assay and Boyden chamber assay. Matrigel invasion assay showed that cell invasion of uveal melanoma cells could be significantly inhibited by zeaxanthin. Secretion of MMP-2 by melanoma cells was significantly inhibited by zeaxanthin in a dose-dependent manner as measured by ELISA kit. Zeaxanthin also significantly inhibited the NF-κB levels in nuclear extracts of the UM cells, which is the upstream of the MMP-2 secretion. These results suggest that zeaxanthin might be a potentially therapeutic approach in the prevention of metastasis in uveal melanoma.

Tanezumab for Patients with Osteoarthritis of the Knee: A Meta-Analysis.

OBJECTIVE: Tanezumab is a new therapeutic intervention for patients with osteoarthritis (OA) of the knee. We performed the present meta-analysis to appraise the efficacy and safety of tanezumab for patients with knee OA. METHODS: We systematically searched randomized controlled trials from PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL). The primary outcomes were mean change in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, the WOMAC physical function and patient's global assessment (PGA). Outcomes were reported as the standard mean difference (SMD) or relative risk (RR) with 95% confidence interval (CI). We assessed the pooled data using a random-effects model. RESULTS: Of the identified studies, four were eligible and were included in this meta-analysis (N = 1839 participants). Compared with the placebo groups, tanezumab yielded a significant reduction in mean change in the WOMAC pain (SMD = 0.51, 95% CI 0.34 to 0.69, P<0.00001), the WOMAC physical function (SMD = 0.56, 95% CI 0.38 to 0.74, P<0.00001) and PGA (SMD = 0.34, 95% CI 0.22 to 0.47, P<0.00001). There was no significant difference in serious adverse events (RR = 1.06, 95% CI 0.59 to 1.92, P = 0.84) between the tanezumab and placebo groups. Tanezumab significantly increased discontinuations due to adverse events (RR = 2.89, 95% CI 1.59 to 5.26, P = 0.0005), abnormal peripheral sensations (RR = 3.14, 95% CI 2.12 to 4.66, P<0.00001), and peripheral neuropathy (RR = 6.05, 95% CI 2.32 to 15.81, P = 0.0002). CONCLUSION: Tanezumab can alleviate pain and improve function for patients with OA of the knee. However, considering the limited number of studies, this conclusion should be interpreted cautiously and more clinical randomized controlled trials are needed to verify the efficacy and safety of tanezumab for OA of the knee.

Effect of endothelial progenitor cells derived from human umbilical cord blood on oxygen-induced retinopathy in mice by intravitreal transplantation.

AIM: To investigate the effect of endothelial progenitor cells (EPCs) labeled by carboxy fluorescein diacetate succinimidyl ester (CFSE) on murine oxygen-induced retinopathy (OIR) by intravitreal transplantation. METHODS: After isolated from human umbilical cord blood mononuclear cells, EPCs were cultivated and then labeled with CFSE in vitro. C57BL/6J mice were placed to 75% hyperoxia chamber from P7 to P12 to establish OIR model. At P12, OIR mice were intravitreally injected with 1 µL suspension contained 2×105 EPCs (EPCs group) or isometric phosphate buffered saline (PBS group). The contralateral eye of each mice received no injection (OIR group). Evans blue angiography and frozen section were examined to track the labeled cells in OIR group at P15 and P19. Using retina paraffin sections and adenosinediphos phatase staining at P12 and P19, the effect of EPCs on OIR mice was evaluated quantitatively and qualitatively. RESULTS: The retinas from EPCs group with less non-perfusion area and fewer peripheral tufts were observed at P19, comparing with that from PBS or OIR group. The retinopathy in EPCs group receded earlier with less non-ganglion cells and neovascular nuclei, together with relatively regular distribution. The counts of the neovascular nuclei at P19 were reduced by 44% or 45%, compared with those of OIR group or PBS group respectively. Three days after EPCs injection, a large number of EPCs appeared in the vitreous cavity and adhered to the retinal surface. While at one week, the cells gathered between the internal plexiform layer and the inner limiting membrane, and some EPCs appeared in retinal vessels. CONCLUSION: EPCs transplantation can participate in the reparative procedure of the neovascularization in OIR.

Zeaxanthin Induces Apoptosis in Human Uveal Melanoma Cells through Bcl-2 Family Proteins and Intrinsic Apoptosis Pathway.

The cytotoxic effects of zeaxanthin on two human uveal melanoma cell lines (SP6.5 and C918) and related signaling pathways were studied and compared to effects on normal ocular cells (uveal melanocytes, retinal pigment epithelial cells, and scleral fibroblasts). MTT assay revealed that zeaxanthin reduced the cell viability of melanoma cells in a dose-dependent manner (10, 30, and 100 µ M), with IC50 at 40.8 and 28.7 µ M in SP6.5 and C918 cell lines, respectively. Zeaxanthin did not affect the viability of normal ocular cells even at the highest levels tested (300 µ M), suggesting that zeaxanthin has a selectively cytotoxic effect on melanoma cells. Zeaxanthin induced apoptosis in melanoma cells as indicated by annexin V and ethidium III flow cytometry. Western blot analysis demonstrated that zeaxanthin decreased the expression of antiapoptotic proteins (Bcl-2 and Bcl-xL) and increased the expression of proapoptotic proteins (Bak and Bax) in zeaxanthin-treated melanoma cells. Zeaxanthin increased mitochondrial permeability as determined by JC-1 fluorescein study. Zeaxanthin also increased the level of cytosol cytochrome c and caspase-9 and -3 activities, but not caspase-8, as measured by ELISA assay or colorimetric assay. All of these findings indicate that the intrinsic (mitochondrial) pathway is involved in zeaxanthin-induced apoptosis in uveal melanoma cells.