ADAMTS5 promotes neovascularization via autophagic degradation of PEDF in proliferative diabetic retinopathy.

Proliferative diabetic retinopathy (PDR) adversely affects visual function. Extracellular matrix proteins (ECM) contribute significantly to the development of PDR. A Disintegrin and Metalloproteinase with Thrombospondin motifs 5 (ADAMTS5) is a member of ECM proteins. ADAMTS5 participates in angiogenesis and inflammation in diverse diseases. However, the role of ADAMTS5 in PDR remains elusive. Multiplex beam array technology was used to analyze vitreous humor of PDR patients and normal people. ELISA and Western blot were used to detect the expression of ADAMTS5, PEDF and autophagy related factors. Immunofluorescence assay was used to mark the expression and localization of ADAMTS5 and PEDF. The neovascularization was detected by tube formation test. Our results revealed that ADAMTS5 expression was increased in the vitreous humor of PDR patients and oxygen-induced retinopathy (OIR) mice retinas. Inhibiting ADAMTS5 alleviated pathological angiogenesis and upregulated PEDF expression in the OIR mice. In addition, ADAMTS5 inhibited PEDF secretion in ARPE-19 cells in vitro studies, thereby inhibiting the migration of HMEC-1. Mechanically, ADAMTS5 promoted the autophagic degradation of PEDF. Collectively, inhibition of ADAMTS5 during OIR suppresses pathological angiogenesis. Our study provides a new approach for resolving pathological angiogenesis in PDR.

Systematic review and meta-analysis of the related factors for diabetic retinopathy.

BACKGROUND: The related factors of diabetic retinopathy (DR) had attracted the attention of many scholars, and a large number of articles had been published, but the research results were not consistent. A meta-analysis was conducted to synthesize recent evidence, aiming at exploring the relationship between DR and multiple risk factors. METHODS: The China National Knowledge Infrastructure, VIP, Wanfang, PubMed, Embase, Medline, and Cochrane databases were searched. The English and Chinese keywords included diabetes mellitus, DM, diabetic retinopathy, DR, and risk factors. In case-control study, the subjects are DR patients and NDR patients. In the cohort study, the subjects were diabetic patients. Measures in the intervention and control groups were described in detail. The methodological quality of the included literature was assessed using the Newcastle-Ottawa Scale (NOS). Egger's test is used to identify publication bias. With odds ratio (OR) as the effect index, heterogeneity test was conducted, and fixed effect model or random effect model was selected to calculate the combined OR and 95% CI. RESULTS: The meta-analysis included 12 literatures and 13 related risk factors, of which 4 (33.33%) were cohort studies and 8 (66.66%) were case-control studies. NOS shows that there are 7 references with 8 points (58.33%), 4 references with 7 points (33.33%) and 1 reference with 6 points (8.33%). The risk factors associated with the occurrence of DR were: course of diabetes (OR =1.03, 95% CI: 1.02-1.03), systolic blood pressure (OR =1.01, 95% CI: 1.01-1.02), body mass index (OR =0.96, 95% CI: 0.94-0.99), HbA1c (OR =1.08, 95% CI: 1.06-1.10), total cholesterol (OR =1.20, 95% CI: 0.98-1.46), high-density lipoprotein cholesterol (OR =1.74, 95% CI: 1.19-2.56), fasting blood glucose (OR =1.19, 95% CI: 1.13-1.26), and hypertension (OR =1.25, 95% CI: 1.07-1.47), and the overall effect test results were statistically significant. Sensitivity analysis results show that the random effect model is used for meta-analysis of all Meta, and the combined OR is 1.10, and the 95% CI is (1.05, 1.15). DISCUSSION: The occurrence of DR was related to the course of diabetes, SBP, HbA1c, total cholesterol, high-density lipoprotein cholesterol, fasting blood glucose, and hypertension which provided a more intuitive and comprehensive scientific basis for the prevention and treatment of DR.

Amino-Nogo inhibits optic nerve regeneration and functional recovery via the integrin αv signaling pathway in rats.

BACKGROUND: Nogo-A, a major myelin-associated inhibitor, can inhibit injured optic nerve regeneration. However, whether Amino-Nogo is the most important functional domain of Nogo-A remains unknown. This study aimed to identify the role of Amino-Nogo following optic nerve injury, and the mechanism of the Amino-Nogo-integrin αv signaling pathway in vivo. METHODS: Sprague-Dawley rats with optic nerve crush injury were injected with Nogo-A siRNA (Nogo-A-siRNA), the Nogo-66 functional domain antagonist peptide of Nogo-A (Nep1-40) or a recombinant rat Amino-Nogo-A protein (∆20) into the vitreous cavity to knock down Nogo-A, inhibit Nogo-66 or activate the Amino-Nogo, resparately. Retinal ganglion cell (RGC) density, axon regeneration and the pattern of NPN of visual electrophysiology (flash visual evoked potentials [F-VEP]) at different times post-injury were investigated. RESULTS: Our study revealed a lower RGC survival rate; shorter axonal outgrowth; longer N1, P1 and N2 waves latencies; and lower N1-P1 and P1-N2 amplitudes in the Δ20 group, and Δ20 treatment significantly attenuated integrin αv expression and phosphorylated focal adhesion kinase (p-FAK) levels. In the Nep1-40 and Nogo-A siRNA groups, there were higher RGC survival rates, longer axonal outgrowth, shorter N1 and P1 wave latencies, and higher N1-P1 and P1-N2amplitudes. Nogo-A siRNA treatment significantly increased integrin αv expression and p-FAK levels. Nepl-40 treatment did not alter integrin αv expression. In addition, there was no significant change in integrin α5 in any group. CONCLUSION: These results suggest that the integrin signaling pathway is regulated by Amino-Nogo, which inhibits optic nerve regeneration and functional recovery, and that the integrin subunit involved might be integrin αv but not integrin α5.

Fluctuations in intraocular pressure increase the trabecular meshwork extracellular matrix.

BACKGROUND/AIMS: The trabecular meshwork (TM) tissue is constantly exposed to dynamic stress caused by intraocular pressure (IOP). The effects of such biomechanical stress on the TM have not been analyzed. This study developed an animal model of fluctuating IOP and evaluated the effects of these fluctuations on TM tissue. METHODS: To create fluctuation in the IOP, one eye of adult SD rats was exposed to cyclic stress with IOP fluctuation ranging from 5 mmHg to 45 mmHg at a 1/60 Hz frequency for 30 minutes every day for several weeks. The other eye was not treated and served as the control. Hematoxylin-eosin staining was used to evaluate changes in the ganglion cells and the morphology, thickness and density of the TM; immunohistochemistry was used to detect α-smooth muscle actin (α-SMA), laminin (LA) and fibronectin (FN) expression in the TM. RESULTS: After several weeks of daily IOP fluctuation, the TM thickness remained unchanged, whereas the density dramatically increased. α-SMA, LA and FN were expressed in rat TM tissue, and the percentages of areas with positive expression significantly increased. The IOP was similar in the treated and control eyes and only tended to increase on day 22 of the experiment. Throughout the 28-day experiment, no ganglion cells were lost. CONCLUSIONS: Large fluctuations in IOP promoted the synthesis of α-SMA, LA and FN in the TM and increased the density of the TM, suggesting that fluctuations in IOP can induce pathological changes in the TM.

Inhibition of retinal ganglion cell axonal outgrowth through the Amino-Nogo-A signaling pathway.

Nogo-A is a myelin-derived inhibitor playing a pivotal role in the prevention of axonal regeneration. A functional domain of Nogo-A, Amino-Nogo, exerts an inhibitory effect on axonal regeneration, although the mechanism is unclear. The present study investigated the role of the Amino-Nogo-integrin signaling pathway in primary retinal ganglion cells (RGCs) with respect to axonal outgrowth, which is required for axonal regeneration. Immunohistochemistry showed that integrin αv, integrin α5 and FAK were widely expressed in the visual system. Thy-1 and GAP-43 immunofluorescence showed that axonal outgrowth of RGCs was promoted by Nogo-A siRNA and a peptide antagonist of the Nogo-66 functional domain of Nogo-A (Nep1-40), and inhibited by a recombinant rat Nogo-A-Fc chimeric protein (Δ20). Western blotting revealed increased integrin αv and p-FAK expression in Nogo-A siRNA group, decreased integrin αv expression in Δ20 group and decreased p-FAK expression in Nep1-40 group. Integrin α5 expression was not changed in any group. RhoA G-LISA showed that RhoA activation was inhibited by Nogo-A siRNA and Δ20, but increased by Nep1-40 treatment. These results suggest that Amino-Nogo inhibits RGC axonal outgrowth primarily through the integrin αv signaling pathway.

Association between MTHFR C677T polymorphism and primary open-angle glaucoma: a meta-analysis.

Epidemiological studies have evaluated the association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and primary open-angle glaucoma (POAG) risk. However, the results remain conflicting. The aim of this study was to investigate the association between MTHFRC677T polymorphism and POAG risk. All genetic association studies on MTHFR C677T polymorphism and POAG were systematically searched by the electronic databases PubMed, Embase and Web of Science. Study selection, data abstraction and study quality evaluation were conducted in duplicate independently. The strength of association between MTHFR C677T polymorphism and POAG was measured by odds ratios (ORs) and 95% confidence intervals (CIs). Publication bias was tested by Begg's funnel plot and Egger's regression test. A total of 10 studies including 1224 cases and 1105 controls were included in our final meta-analysis. There was no evidence of significant association of the overall population (for allelic model: OR=1.17, 95% CI=0.94-1.46; for additive model: OR=1.15, 95% CI=0.85-1.57; for dominant model: OR=1.19, 95% CI=0.92-1.55 and for recessive model: OR=1.11, 95% CI=0.83-1.49). Significant associations were found between MTHFR C677T polymorphisms and POAG in allelic model (OR=1.39, 95% CI=1.05-1.83) and additive model (OR=1.88, 95% CI=1.04-3.43) for population-based (PB) subgroup. This meta-analysis suggested that there were significant associations between MTHFR C677T polymorphism and POAG in allelic model and additive model for PB subgroup which indicated that the T allele or TT genotype might increase the risk of POAG, whereas no evidence of significant association was shown of the overall studied population. However, this conclusion should be interpreted cautiously. More large sample-size and multi-ethnicity studies with well-defined POAG patients and well-study design are needed in the future study.

Clinical features of ankylosing spondylitis associated with acute anterior uveitis in Chinese patients.

AIM: To characterize the clinical features, diagnosis, treatment and prognosis of uveitis associated with ankylosing spondylitis (AS) in Chinese patients. METHODS: Two hundred and three patients with uveitis associated with AS followed-up in the Third Military Medical University Daping Hospital between 2005 and 2010 were retrospectively evaluated in this study. Complete ophthalmological examinations were evaluated at baseline and during the follow-up period. The gender, age, follow-up time, mean frequency of uveitis onset, and accompanying eye examination findings, history, demographical parameters were reviewed. All the patients presented complete clinical and radiologic (sacroiliac, lumbar, dorsal and cervical spine, knee, ankle, shoulder, hip, elbow) evaluation. HLA-B27 typing was also searched. RESULTS: There were 203 patients diagnosed with AS associated uveitis. All showed sacroiliac X-ray changes indicative of AS. There were 184 male and 19 female patients. The average age of patients was 35±12 (range 18-50). Mean follow-up period was 2.4 years (1-5 years). Acute anterior uveitis was the most common type of uveitis in both genders. 121 eyes presented unilateral involvement (55.2%), and 92 eyes presented bilateral involvement (45.3%) with onset alternately. 22 eyes occurred hypopyon, 16 eyes were found anterior vitreous cells, 7 eyes were noted reactive macular edema or exudation, 29 eyes presented posterior synechiae of iris, and 14 eyes presented cataract, 9 eyes presented secondary glaucoma, 2 eyes presented bend corneal degeneration and 1 eyes presented atrophy of eyeball. At the final visit, uveitis was well controlled in most patients. CONCLUSION: AS associated with uveitis in Chinese patients mainly manifests as acute anterior uveitis. A combination of corticosteroids with other mydriasis agents is effective for most AS associated with uveitis patients. In general, the prognosis is good in these cases.

Effect of CD4(+)CD25(+) regulatory T cells in the development of anterior chamber-associated immune deviation.

AIM: To investigate whether CD4(+)CD25(+) regulatory T (Treg) cells play a role in the development of anterior chamber-associated immune deviation (ACAID). METHODS: The dynamic changes in the frequency of CD4(+)CD25(+) T cells, CD4(+)CD25(+) FoxP3(+) T cells and CD4(+)CD25(+) PD-1(+) T cells from spleens of mice with ACAID were analyzed by flow cytometry. Foxp3 mRNA expression in purified CD4(+)CD25(+) T cells was analyzed using real-time PCR. The suppressive effect of purified CD4(+)CD25(+) T cells on the proliferation of CD4(+)CD25(-) T cells was evaluated by [(3)H] thymidine incorporation. A blocking experiment was performed to further address the role of CD4(+)CD25(+) T cells in ACAID. The expression of IL-10 in purified CD4(+)CD25(+) T cells was evaluated by ELISA. RESULTS: Increased frequencies of CD4(+)CD25(+) T cells, CD4(+)CD25(+) FoxP3(+) T cells and CD4(+)CD25(+) PD-1(+) T cells were observed in ACAID. The CD4(+)CD25(+) T cells from mice with ACAID showed enhanced suppressive effect on the proliferation of CD4(+)CD25(-) T cells. Treatment of BALB/c mice with anti-CD25 antibody after injection of OVA into the anterior chamber significantly inhibited the induction of ACAID. Furthermore, purified CD4(+)CD25(+) T cells from ACAID mice secreted IL-10. CONCLUSION: Our results demonstrate that Treg cells are induced in the mice undergoing ACAID. These Treg cells may play a role in the development of ACAID.

A case of circumscribed choroidal hemangioma in Sturge-Weber syndrome in China.

We present a case of circumscribed choroidal hemangioma (CCH) in Sturge-Weber syndrome in a 30-year-old woman with congenital port-wine stains on the left side of face involving the upper eyelid, cheek and the nose, and she had undergone facial hemangioma surgery 3 years ago suggestive of Sturge-Weber syndrome. She presented with a 1-month history of rapidly decreased visual acuity (VA) to counting fingers in the left eye which had no prior history of visual problem. And there was no evidence of glaucoma. At 3 months after the treatment of the standard photodynamic therapy (PDT) the VA was 20/200. For some reasons, we have no idea about the changes of tumor thickness and subretinal fluid. We confirmed the curative effect of PDT treatment for CCH because of the significantly improved VA in the bad eye.

Bietti crystalline dystrophy with bilateral macular holes.

OBJECTIVE: Bietti crystalline dystrophy is a rare form of tapetoretinal degeneration associated with retinal crystalline deposits. However, Bietti crystalline dystrophy is extremely unusually associated with macular hole formation. A 32-year-old man with Bietti crystalline dystrophy and bilateral macular holes is described. DESIGN: Case report and literature review. RESULTS: Clinical and angiographic features, optical coherence tomography results, electroretinographic findings, and visual evoked potentials are reported. CONCLUSION: Bietti crystalline dystrophy can occur with bilateral macular holes, but the cause is unclear.

[Collagen synthesis and expression of connective tissue growth factor in the cultured fibroblasts of human hypertrophic scar].

OBJECTIVE: To explore the effect of connective tissue growth factor on the pathogenesis of human hypertrophic scar. METHODS: Normal skin and hypertrophic scar fibroblasts were cultured in vitro. The collagen synthesis of fibroblasts were measured by H3-proline incorporation method. The expression of connective tissue growth factor protein and mRNA of fibroblasts were detected with immunocytochemistry staining and reverse transcription polymerase chain reaction methods. RESULTS: Compared with normal skin fibroblast, the collagen synthesis and the expression of connective tissue growth factor protein and mRNA in the hypertrophic scar fibroblast was higher (P < 0.01). CONCLUSION: Connective tissue growth factor may play an important role in promoting the fibrotic process of hypertrophic scar.

[Effects of antisense oligonucleotides on the expression of connective tissue growth factor gene and on the collagen synthesis in the cultured human keloid fibroblasts].

OBJECTIVE: To study the role of connective tissue growth factor (CTGF) in the pathogenesis of human keloid. METHODS: Human keloid fibroblasts (HKF) were isolated from human keloid and cultured in vitro. The cells were then divided into 3 groups according to different processing, i.e. ASODN treatment (AT), in which phosphorothioate CTGF antisense oligonucleotides (ASODN) labeled by fluorescent isothiocyananate were transfected into the HKFs by liposome; liposome control (LC, with liposome only); control groups (without liposome or ASODN). The distribution of CTGF ASODN in all groups of cells was observed under fluorescent microscope. The CTGF mRNA index (RI) of HKF was assessed by reverse transcription polymerase chain reaction method (RT-PCR). The collagen synthesis of HKF was assessed by (3)H-proline incorporation method. RESULTS: A large amount of fluorescence could be observed in the cytoplasm of HKFs in AT 12 hours after transfection, but not in LC and C groups. The CTGF mRNA index of HKF in AT group 48 hours after transfection was significantly lower than that in LC and C groups (0.12 +/- 0.62 vs 0.51 +/- 0.18 vs 0.54 +/- 0.35, P < 0.01). The (3)H-proline incorporation rate in AT group (108.96 +/- 79.05) was lower than that in LC and C groups (P < 0.01). CONCLUSION: The expression of CTGF gene and collagen synthesis of the cultured HKF could be inhibited by CTGF ASODN, implying that CTGF played a role in the development of excessive fibrosis of human keloid.

[Effects of connective tissue growth factor antisense oligonucleotides on the cultured human keloid fibroblasts in vitro].

OBJECTIVE: To explore the effects of connective tissue growth factor (CTGF) on the pathogenesis of human keloid. METHODS: CTGF antisense oligonucleotides (ASODN) conjugated with isothiocyanate fluorescence was encapsulated by liposome, and then added into the human keloid fibroblast (HKF) culturing media. The intracellular distribution of CTGF ASODN was observed with fluorescence microscopy in the fixed HKF. The proliferation of HKF was measured by MIT test. The apoptosis of HKF was measured with a flow cytometer. The collagen synthesis of HKF was measured by using H3-proline incorporation method. RESULTS: The CTGF ASODN inhibited the proliferation and collagen synthesis of the HKF, compared with the control, but it increased the apoptosis after the transfection (P < 0.01). CONCLUSION: CTGF ASODN may has anti-fibrotic effects on human keloid in vitro, and the CTGF may play an important role in promoting the fibrosis of human keloid.

[Expression of connective tissue growth factor gene in the hypertrophic scar and keloid tissue].

OBJECTIVE: To explore the effect of connective tissue growth factor on the pathogenesis of hypertrophic scar and keloid tissue. METHODS: The content of hydroxyproline was determined and the expression of connective tissue growth factor gene was detected by the reverse transcription-polymerase chain reaction and image analysis technique in 5 normal skins, 15 hypertrophic scars and 7 keloid tissues. RESULTS: The contents of hydroxyproline in the hypertrophic scar (84.10 +/- 1.76) and keloid tissue (92.38 +/- 2.04) were significantly higher than that of normal skin tissue (26.52 +/- 4.10) (P < 0.01). The index of connective tissue growth factor mRNA in the hypertrophic scar (0.78 +/- 0.63) and keloid tissue (0.84 +/- 0.04) were higher than that of normal skin tissue (0.09 +/- 0.25) (P < 0.01). CONCLUSION: Connective tissue growth factor may play an important role in promoting the fibrotic process of hypertrophic scar and keloid tissue.