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1.
Cell Death Discov ; 10(1): 126, 2024 Mar 09.
Article En | MEDLINE | ID: mdl-38461179

Excessive uric acid (UA) is associated with age-related cataract. A previous study showed that a high UA level in the aqueous humor stimulated the senescence of lens epithelial cells (LECs), leading to cataract progression. To better understand the underlying mechanisms, we investigated UA-driven senescence in human lens tissue samples obtained during surgery, rat lens organ cultures, and in vivo experiments, using senescence-associated ß-galactosidase (SA-ß-gal) staining, electronic microscopy, Western blotting, and histological analyses. Initially, we identified markedly higher expressions of NLRP3 and caspase-1 in the lens capsules of hyper-uricemic patients compared to normo-uricemic patients. This increase was accompanied by a significant rise in the SA-ß-gal positive rate. We next built a cataract model in which rat lenses in an organ culture system were treated with an increasing dosage of UA. Notably, opacification was apparent in the lenses treated with 800 µM of UA starting on the fifth day. Mechanistically, UA treatment not only significantly induced the expression of NLRP3, caspase-1, and IL-1ß, but also upregulated the levels of SA-ß-gal and the senescence regulators p53 and p21. These effects were fully reversed, and lens opacification was ameliorated by the addition of MCC950, a selective NLRP3 antagonist. Moreover, an in vivo model showed that intravitreal UA injection rapidly induced cataract phenotypes within 21 days, an effect significantly mitigated by co-injection with MCC950. Together, our findings suggest that targeting the UA-induced NLRP3 inflammasome with MCC950 could be a promising strategy for preventing cataract formation associated with inflammageing.

3.
Retina ; 42(6): 1121-1129, 2022 06 01.
Article En | MEDLINE | ID: mdl-35174802

PURPOSE: To determine the association of uric acid (UA) and glucose in aqueous humor with diabetic macular edema (DME) in patients with Type 2 diabetes. METHODS: Patients with DME or diabetes mellitus without retinopathy were enrolled from August 2016 to December 2020. Nondiabetic patients with age-related cataract or age-related macular degeneration were included as controls. RESULTS: A total of 585 eyes from 585 patients were included for this study. Statistical analysis showed that aqueous UA was associated with central retinal thickness (r = 0.39, P < 0.0001), with higher levels of UA in severe DME and lower levels in mild DME, suggesting an ocular source of UA from the diabetic retina. Aqueous UA {odds ratio (OR), 6.88 (95% confidence interval [CI], 2.61-18.12)}, but not aqueous glucose (0.95 [95% CI, 0.73-1.23]) or serum UA (0.90 [95% CI, 0.66-1.23]), was a stronger predictor for DME than the duration of DM (1.26 [95% CI, 1.12-1.42]) or hemoglobin A1c (1.35 [95% CI, 0.99-1.83]). If aqueous UA (<2.46 mg/dL) and aqueous glucose (<6.43 mmol/L) were used as reference, high UA (≥2.46 mg/dL) alone was associated with 5.83-fold increase in risk of DME, but high glucose (≥6.43 mg/dL) alone was not associated with DME. CONCLUSION: Increased aqueous UA, but not glucose, is an independent risk factor for DME. These data suggest that an intravitreal UA-lowering therapy could be beneficial for DME.


Diabetes Mellitus, Type 2 , Diabetic Retinopathy , Macular Edema , Aqueous Humor , Diabetes Mellitus, Type 2/complications , Diabetic Retinopathy/complications , Diabetic Retinopathy/diagnosis , Glucose , Humans , Macular Edema/complications , Macular Edema/etiology , Risk Factors , Uric Acid
4.
Proc Natl Acad Sci U S A ; 118(28)2021 07 13.
Article En | MEDLINE | ID: mdl-34244423

Optic neuropathies are leading causes of irreversible visual impairment and blindness, currently affecting more than 100 million people worldwide. Glaucoma is a group of optic neuropathies attributed to progressive degeneration of retinal ganglion cells (RGCs). We have previously demonstrated an increase in survival of RGCs by the activation of macrophages, whereas the inhibition of macrophages was involved in the alleviation on endotoxin-induced inflammation by antagonist of growth hormone-releasing hormone (GHRH). Herein, we hypothesized that GHRH receptor (GHRH-R) signaling could be involved in the survival of RGCs mediated by inflammation. We found the expression of GHRH-R in RGCs of adult rat retina. After optic nerve crush, subcutaneous application of GHRH agonist MR-409 or antagonist MIA-602 promoted the survival of RGCs. Both the GHRH agonist and antagonist increased the phosphorylation of Akt in the retina, but only agonist MR-409 promoted microglia activation in the retina. The antagonist MIA-602 reduced significantly the expression of inflammation-related genes Il1b, Il6, and Tnf Moreover, agonist MR-409 further enhanced the promotion of RGC survival by lens injury or zymosan-induced macrophage activation, whereas antagonist MIA-602 attenuated the enhancement in RGC survival. Our findings reveal the protective effect of agonistic analogs of GHRH on RGCs in rats after optic nerve injury and its additive effect to macrophage activation, indicating a therapeutic potential of GHRH agonists for the protection of RGCs against optic neuropathies especially in glaucoma.


Growth Hormone-Releasing Hormone/agonists , Macrophages/pathology , Neuroprotection , Optic Nerve Injuries/pathology , Retinal Ganglion Cells/pathology , Animals , Cell Survival/drug effects , Gene Expression Regulation/drug effects , Growth Hormone/metabolism , Growth Hormone-Releasing Hormone/antagonists & inhibitors , Inflammation/genetics , Inflammation/pathology , MAP Kinase Signaling System/drug effects , Macrophages/drug effects , Macrophages/metabolism , Male , Microglia/drug effects , Microglia/metabolism , Microglia/pathology , Neuroprotection/drug effects , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Rats, Inbred F344 , Receptors, Neuropeptide/metabolism , Receptors, Pituitary Hormone-Regulating Hormone/metabolism , Retinal Ganglion Cells/drug effects , Retinal Ganglion Cells/metabolism , STAT3 Transcription Factor/metabolism , Sermorelin/analogs & derivatives , Sermorelin/pharmacology , Signal Transduction/drug effects , Vitreous Body/drug effects , Vitreous Body/metabolism , Zymosan/pharmacology
5.
Exp Eye Res ; 204: 108447, 2021 03.
Article En | MEDLINE | ID: mdl-33465394

We previously found that epigallocatechin-3-gallate (EGCG) could inhibit the myofibroblast transformation of human Tenon's fibroblasts, however, the underlying mechanism remained unclear. We therefore investigated whether the autophagic regulation involved in the anti-fibrotic function of EGCG. The fibroblasts were subjected to transforming growth factor beta-1 (TGF-ß1) induction followed by EGCG treatments. The autophagic flux was examined by transmission electron microscopy and autophagic flux analysis. The levels of autophagy-related proteins (LC3ß and p62) and alpha-smooth muscle actin (α-SMA) were measured by Western blot and immunofluorescence. Results showed that TGF-ß1 partially inhibited the autophagic function of Tenon's fibroblasts. But this inhibition effect was rescued by LY2157299, a TGF-ßR1 selective inhibitor. Compared with the cells treated with TGF-ß1 alone, EGCG treatments increased the amount of autophagosomes and autolysosomes, evaluated the ratio of LC3-II to LC3-I and decreased p62 level. Our results indicated that EGCG could recover the activity of autophagy in the TGF-ß1-treated cells. Moreover, treatments with EGCG significantly decreased the α-SMA expression. Taken together, these findings revealed that autophagic regulation involved in the action of EGCG against TGF-ß1-induced transformation of Tenon's fibroblasts. Through increasing intracellular autophagy, EGCG could be a potential anti-fibrotic reagent for preventing subconjunctival fibrosis after glaucoma filtration surgery.


Antioxidants/pharmacology , Autophagy/drug effects , Catechin/analogs & derivatives , Myofibroblasts/drug effects , Tenon Capsule/drug effects , Transforming Growth Factor beta1/pharmacology , Actins/metabolism , Adenoviridae/genetics , Blotting, Western , Catechin/pharmacology , Cell Transdifferentiation/drug effects , Cells, Cultured , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Humans , Microscopy, Electron, Transmission , Microscopy, Fluorescence , Microtubule-Associated Proteins/metabolism , Myofibroblasts/metabolism , Myofibroblasts/ultrastructure , Sequestosome-1 Protein/metabolism , Tenon Capsule/metabolism , Tenon Capsule/ultrastructure , Transfection , Transforming Growth Factor beta1/antagonists & inhibitors
6.
J Ophthalmol ; 2020: 6974202, 2020.
Article En | MEDLINE | ID: mdl-32802489

PURPOSE: To compare ocular anatomy differences of lens subluxation between eyes with or without acute angle closure (AAC). METHODS: This is a retrospective and case-control study. Sixty cases with mild lens subluxation were recruited. Among them, 30 eyes with acute angle closure were assigned to the AAC group and 30 eyes without AAC were assigned to the non-AAC group. The anterior segment was quantitatively evaluated by ultrasound biomicroscopy (UBM). The axial length (AL) was measured with IOL Master. All patients underwent lens extraction surgery and were followed up for six months. RESULTS: The history of blunt trauma accounted for 22 (73.3%) cases in the AAC group and 21 (70%) cases in the non-AAC group. Fifteen (50%) patients in the AAC group had iridotomy history, and high intraocular pressure recurred. The UBM analysis showed that the average central chamber depth of the affected eyes in the AAC group was 1.82 mm, which was significantly shallower than that in the fellow eyes (2.58 mm, P < 0.05) or both eyes in the non-AAC group.Both eyes in the AAC group presented a shorter AL and shallower anterior chamber than the eyes in the non-AAC group. CONCLUSIONS: An asymmetrical anterior chamber between bilateral eyes is an important feature in lens subluxation-induced AAC. The crowded anterior chamber and shorter AL might be the anatomic basis for the eye with lens subluxation-induced AAC.

7.
Exp Eye Res ; 197: 108119, 2020 08.
Article En | MEDLINE | ID: mdl-32603658

Myofibroblast transformation of human Tenon's fibroblasts severely challenges the outcome of glaucoma filtration surgery. epigallocatechin-3-gallate (EGCG) is considered as a potential reagent to overcome this issue for its anti-fibrosis effect on various human diseases, but it is unclear on the fibrosis of Tenon's fibroblasts. This study was conducted to investigate the effect of EGCG on TGF-ß1-induced myofibroblast transformation of human Tenon's fibroblasts. The human Tenon's fibroblasts were incubated in the medium containing 10 ng/mL TGF-ß1, and subsequently treated with EGCG or mitomycin C (MMC). The cell proliferation and migration were analyzed. The expression of alpha-smooth muscle actin (α-SMA), type I collagen (Col-I), and p-Smad2/3 were also evaluated. It showed that EGCG and MMC strongly inhibited the elevation in cell number in tissue explants compared to the tissues treated with TGF-ß1 alone. Scratch-Wound assay showed that 48 h after TGF-ß1 induction, only 10% of the wound width remained. But cells treated with EGCG still showed over 93% wound width. Further, EGCG effectively inhibited TGF-ß1-induced expression of α-SMA and Col-I as well as phosphorylation of Smad2/3 in Tenon's fibroblasts. Altogether, we concluded that EGCG suppressed the myofibroblast transformation in Tenon's fibroblasts through inactivating TGF-ß1/Smad signaling. These findings demonstrate that EGCG can be considered as one of the possible antifibrotic reagents for preventing postoperative scarring in glaucoma filtration surgery.


Catechin/analogs & derivatives , Glaucoma/drug therapy , Myofibroblasts/metabolism , Tenon Capsule/metabolism , Catechin/pharmacology , Cell Movement/drug effects , Cell Proliferation/drug effects , Cells, Cultured , Fibroblasts/drug effects , Fibroblasts/metabolism , Fibroblasts/pathology , Glaucoma/metabolism , Glaucoma/pathology , Humans , Myofibroblasts/drug effects , Myofibroblasts/pathology , Neuroprotective Agents/pharmacology , Protease Inhibitors , Signal Transduction , Tenon Capsule/drug effects , Tenon Capsule/pathology
8.
Clin Exp Ophthalmol ; 48(9): 1183-1191, 2020 12.
Article En | MEDLINE | ID: mdl-32713071

IMPORTANCE: Age-related cataract is the leading cause of blindness worldwide. The pathological mechanisms causing this disease remain elusive. BACKGROUND: To examine the involvement of uric acid (UA) in the pathogenesis of posterior subcapsular cataract (PSC). DESIGN: Retrospective study and experimental investigation. PARTICIPANTS: A total of 180 patients with PSC or non-PSC were included. METHODS: Samples obtained from the patients were used to analyse content of UA and for histochemical examinations. The effects of UA on human lens epithelial cells were also investigated. MAIN OUTCOME MEASURES: Aqueous humour UA and urate deposits. RESULTS: The results showed a significant increase of aqueous humour UA in patients with PSC. After adjustment for potential confounders, elevated aqueous humour UA (odds ratio [OR] = 1.45) showed a stronger association with PSC than serum UA (OR = 1.10). Gomori methenamine silver staining revealed in PSC an intense deposit of urates in the lens fibres in equatorial regions, and in subcapsular fibres in posterior regions of the lens. Such staining was not detected in the lens with non-PSC. Treatment with UA-induced senescence and apoptosis in human lens epithelial cells in a dose dependent manner. Our results suggest that the elevated level of UA in aqueous humour causes a deposition of urates in human lens epithelium, which could possibly lead to dysfunction of these cells that generates opacification in PSC. CONCLUSIONS AND RELEVANCE: These findings indicate the local action of excessive UA in the pathogenesis of PSC. Control of serum UA level could delay the progression of PSC.


Cataract , Lens, Crystalline , Aqueous Humor , Humans , Retrospective Studies , Uric Acid
9.
Proc Natl Acad Sci U S A ; 117(11): 6067-6074, 2020 03 17.
Article En | MEDLINE | ID: mdl-32123064

Ocular inflammation is a major cause of visual impairment attributed to dysregulation of the immune system. Previously, we have shown that the receptor for growth-hormone-releasing hormone (GHRH-R) affects multiple inflammatory processes. To clarify the pathological roles of GHRH-R in acute ocular inflammation, we investigated the inflammatory cascades mediated by this receptor. In human ciliary epithelial cells, the NF-κB subunit p65 was phosphorylated in response to stimulation with lipopolysaccharide (LPS), resulting in transcriptional up-regulation of GHRH-R. Bioinformatics analysis and coimmunoprecipitation showed that GHRH-R had a direct interaction with JAK2. JAK2, but not JAK1, JAK3, and TYK2, was elevated in ciliary body and iris after treatment with LPS in a rat model of endotoxin-induced uveitis. This elevation augmented the phosphorylation of STAT3 and production of proinflammatory factors, including IL-6, IL-17A, COX2, and iNOS. In explants of iris and ciliary body, the GHRH-R antagonist, MIA-602, suppressed phosphorylation of STAT3 and attenuated expression of downstream proinflammatory factors after LPS treatment. A similar suppression of STAT3 phosphorylation was observed in human ciliary epithelial cells. In vivo studies showed that blocking of the GHRH-R/JAK2/STAT3 axis with the JAK inhibitor Ruxolitinib alleviated partially the LPS-induced acute ocular inflammation by reducing inflammatory cells and protein leakage in the aqueous humor and by repressing expression of STAT3 target genes in rat ciliary body and iris and in human ciliary epithelial cells. Our findings indicate a functional role of the GHRH-R/JAK2/STAT3-signaling axis in acute anterior uveitis and suggest a therapeutic strategy based on treatment with antagonists targeting this signaling pathway.


Epithelial Cells/pathology , Receptors, Neuropeptide/metabolism , Receptors, Pituitary Hormone-Regulating Hormone/metabolism , Signal Transduction/immunology , Uveitis/pathology , Animals , Cell Line , Ciliary Body/cytology , Disease Models, Animal , Epithelial Cells/drug effects , Epithelial Cells/immunology , Humans , Janus Kinase 2/metabolism , Lipopolysaccharides/immunology , Male , Nitriles , Pyrazoles/pharmacology , Pyrazoles/therapeutic use , Pyrimidines , Rats , Receptors, Neuropeptide/antagonists & inhibitors , Receptors, Neuropeptide/immunology , Receptors, Pituitary Hormone-Regulating Hormone/antagonists & inhibitors , Receptors, Pituitary Hormone-Regulating Hormone/immunology , STAT3 Transcription Factor/metabolism , Sermorelin/analogs & derivatives , Sermorelin/pharmacology , Sermorelin/therapeutic use , Signal Transduction/drug effects , Uveitis/drug therapy , Uveitis/immunology
10.
Am J Ophthalmol ; 215: 81-90, 2020 07.
Article En | MEDLINE | ID: mdl-32061756

PURPOSE: To investigate the involvement of growth hormone-releasing hormone (GHRH) - growth hormone (GH) signaling in pathogenesis of proliferative diabetic retinopathy (PDR). DESIGN: Experimental laboratory study. METHODS: Vitreous humor, aqueous humor, and serum were obtained from 36 eyes of 36 patients with or without type 2 diabetes from 2017 to 2019. For histologic examination, 6 fibrovascular membranes were excised from eyes with active PDR. Three fibrovascular membranes were excised from nondiabetic patients with proliferative vitreoretinopathy (PVR) as controls. RESULTS: In PDR, the fibrovascular tissues consisted of a mature region containing fibrocytes, and an immature region populated by abundant polymorphonuclear leukocytes in a fibrinogen meshwork. Clusters of leukocytes were found adhering to the vascular walls. In PVR, no fibrinogen and polymorphonuclear leukocyte was observed in the fibrovascular membranes. The levels of GHRH and GH in PDR were significantly increased (P < .001), with 1.8-fold and 72.8-fold in vitreous humor, and 2-fold and 4.9-fold in aqueous humor, respectively, when compared with corresponding levels in controls. No significant difference was detected for insulin-like growth factor-1. Immunohistochemistry showed intense expression of GHRH and its receptor GHRH-R in polymorphonuclear leukocytes, vascular endothelial cells, and fibrocytes in fibrovascular membranes of PDR. GHRH staining was not detectable in infiltrating cells within the fibrovascular membrane of PVR. CONCLUSIONS: These findings reveal a possible involvement of GHRH/GHRH-R in fibrinous inflammation that might contribute to the formation of fibrovascular membrane in PDR through mediating activities of leukocytes, vascular endothelial cells, and fibrocytes. Targeting GHRH/GHRH-R may be considered as a potential therapeutic approach for the treatment of PDR.


Aqueous Humor/metabolism , Diabetic Retinopathy/blood , Growth Hormone-Releasing Hormone/blood , Inflammation/blood , Receptors, Neuropeptide/blood , Receptors, Pituitary Hormone-Regulating Hormone/blood , Vitreous Body/metabolism , Adult , Aged , Diabetes Mellitus, Type 2/metabolism , Endothelium, Vascular/metabolism , Enzyme-Linked Immunosorbent Assay , Female , Fibroblasts/metabolism , Humans , Male , Middle Aged , Neutrophils/metabolism
11.
Invest Ophthalmol Vis Sci ; 59(12): 5060-5066, 2018 10 01.
Article En | MEDLINE | ID: mdl-30357400

Purpose: The aim of the study was to investigate the signaling of growth hormone-releasing hormone receptor (GHRH-R) in the pathogenesis of pterygium and determine the apoptotic effect of GHRH-R antagonist on pterygium epithelial cells (PECs). Methods: Fourteen samples of primary pterygium of grade T3 with size of corneal invasion ≥ 4 mm were obtained for investigation by histology, immunofluorescence, electron microscopy, explant culture, and flow cytometry. Results: We found that PECs were localized in the basal layer of the epithelium in advancing regions of the head of pterygium. These cells harbored clusters of rough endoplasmic reticulum, ribosomes, and mitochondria, which were consistent with their aggressive proliferation. Immunofluorescence studies and Western blots showed that GHRH-R and the downstream growth hormone receptor (GH-R) were intensively expressed in PECs. Their respective ligands, GHRH and GH, were also elevated in the pterygium tissues as compared to conjunctival cells. Explanted PECs were strongly immunoreactive to GHRH-R and exhibited differentiation and proliferation that led to lump formation. Treatment with GHRH-R antagonist MIA-602 induced apoptosis of PECs in a dose-dependent manner, which was accompanied by a downregulation of ERK1 and upregulation of Caspase 3 expression. Conclusions: Our results revealed that GHRH-R signaling is involved in survival and proliferation of PECs and suggest a potential therapeutic approach for GHRH-R antagonist in the treatment of pterygium.


Apoptosis/drug effects , Pterygium/pathology , Receptors, Neuropeptide/antagonists & inhibitors , Receptors, Pituitary Hormone-Regulating Hormone/antagonists & inhibitors , Sermorelin/analogs & derivatives , Blotting, Western , Caspase 3/metabolism , Cell Count , Cell Proliferation , Cell Survival , Epithelial Cells/metabolism , Epithelial Cells/pathology , Fluorescent Antibody Technique, Indirect , Growth Hormone/metabolism , Growth Hormone-Releasing Hormone/metabolism , Humans , Microscopy, Electron, Transmission , Mitogen-Activated Protein Kinase 3/metabolism , Pterygium/metabolism , Real-Time Polymerase Chain Reaction , Receptors, Neuropeptide/metabolism , Receptors, Pituitary Hormone-Regulating Hormone/metabolism , Receptors, Somatotropin/metabolism , Sermorelin/pharmacology , Signal Transduction
12.
BMC Ophthalmol ; 18(1): 210, 2018 Aug 28.
Article En | MEDLINE | ID: mdl-30153816

BACKGROUND: To report a case of femtosecond laser-assisted removal of an intracorneal chestnut. CASE PRESENTATION: A chestnut was obliquely protruding to the stroma of cornea and it was localized at the paracentral region on the left eye of a 32-year-old man. The best-corrected visual acuity (BCVA, in decimal values) was 0.6 in the injured eye. The white ulcers with feathery edges or satellite infiltrates were not observed in the lesion, and the anterior chamber was deep and quiet. Anterior segment optical coherence tomography (AS-OCT) demonstrated that the original entry path of the foreign body had been sealed, spanning a thickness of approximate 152 µm. In view of location of the intraocular chestnut at the paracentral region, femtosecond laser was applied according to the procedures of IntraLase Enabled Keratoplasty (IEK) to create an anterior lamellar flap rapidly and precisely. The lamellar flap was easily separated with a flap lifter, and the chestnut was removed entirely using a pair of forceps. In 3 days after surgery, the patient complained of mild pain and blurred vision. These symptoms were relieved after treatment with the eyedrops. At three-month follow-up, the corneal wound was healed well, and the BCVA was greatly improved to 1.2 in the left eye. A dot-like haze was observed corresponding to the scar at the site of foreign body removal. No surgical induction of corneal astigmatism was found in the corneal topography. CONCLUSIONS: Without induction of a visually significant scar and corneal astigmatism, the IEK procedure of femtosecond laser is of particular interest as it provides a unique method for removal of intracorneal foreign bodies impinging on the visual axis.


Corneal Diseases/surgery , Corneal Transplantation/methods , Eye Foreign Bodies/surgery , Lasers, Excimer/therapeutic use , Nuts , Adult , Humans , Male , Treatment Outcome
13.
Int J Ophthalmol ; 9(11): 1555-1560, 2016.
Article En | MEDLINE | ID: mdl-27990356

AIM: To investigate the role of microRNA-34a (miR-34a) in the induction of apoptosis of human lens epithelial (HLE-B3) cells. METHODS: The apoptosis of HLE-B3 cells was detected by Annexin V-PE apoptosis detection kit after the treatment with 200 µmol/L H2O2 for 24h and lentiviral miR-34a vector transfection. The expression of miR-34a in the cells was quantified by quantitative real time polymerase chain reaction (qRT-PCR) in response to H2O2 exposure and the vector transfection. The effects of overexpression of miR-34a on the expression of B-cell lymphoma-2 (Bcl-2) and silent information regulator 1 (SIRT1) was determined by qRT-PCR and Western blot. RESULTS: The expression of miR-34a was up-regulated by the treatment of H2O2 in HLE-B3 cells. The increased expression of miR-34a is accompanied with the cell apoptosis. Consistence with the H2O2 exposure, ectopic overexpression of miR-34a in HLE-B3 cells promoted cells apoptosis. Importantly the anti-apoptosis factors Bcl-2 and SIRT1 were reduced significantly by up-regulation of miR-34a in HLE-B3 cells. CONCLUSION: MiR-34a promotes the apoptosis of HLE-B3 cells by down-regulating Bcl-2 and SIRT1, suggesting that miR-34a may involve in the pathogenesis of cataract formation and targeting miR-34a may be a potentially therapeutic approach for treatment of cataract.

14.
J Ophthalmol ; 2016: 2153723, 2016.
Article En | MEDLINE | ID: mdl-27529032

Purpose. To compare the efficacy of subthreshold and conventional selective laser trabeculoplasty (SLT) in lowering intraocular pressure (IOP) in the patients with primary open-angle glaucoma (POAG). Methods. Fifty-two eyes from fifty-two POAG patients were randomized into two groups, one group treated with subthreshold SLT using two-thirds of the conventional energy and the other one treated with the conventional energy. IOP was measured with the Goldmann tonometer and the anterior chamber inflammation was determined using laser flare meter. Results. The initial energy dosage used in subthreshold SLT group was significantly lower than the amount of the energy used in conventional SLT group (0.4 ± 0.1 mJ versus 0.6 ± 0.1 mJ, P = 0.030). The total energy dosage was also significantly lower in subthreshold SLT group compared to the other group (37.6 ± 3.3 mJ versus 51.8 ± 5.7 mJ, P = 0.036). However, the level of inflammation in aqueous humor, amount of reduction in IOP, and the success rate in controlling IOP was the same in both groups. Conclusion. The efficacy of subthreshold SLT group in reducing IOP in POAG patients is comparable to the efficacy of conventional SLT group.

15.
Sci Rep ; 6: 29546, 2016 07 07.
Article En | MEDLINE | ID: mdl-27383468

Green tea extracts exhibit anti-oxidative and anti-inflammatory actions in different disease conditions. We hypothesized that green tea extract and its catechin constituents ameliorate sodium iodate-induced retinal degeneration in rats by counteracting oxidative stress. In this study, adult Sprague-Dawley rats were intravenously injected with a single dose of sodium iodate. Green tea extract (GTE; Theaphenon-E) or combinations of its catechin constituents, including (-)-epigallocatechin gallate (EGCG), were administered intra-gastrically before injection. Live imaging analysis using confocal scanning laser ophthalmoscopy and spectral-domain optical coherence tomography showed a progressive increase of degenerating profile across the retinal surface and decrease in thickness of outer nuclear layer (ONL) at Day-14 of post-injection. These lesions were significantly ameliorated by Theaphenon-E and catechin combinations with EGCG. Catechins with exclusion of EGCG did not show obvious protective effect. Histological analyses confirmed that Theaphenon-E and catechins containing EGCG protect the retina by reducing ONL disruption. Retinal protective effects were associated with reduced expression of superoxide dismutase, glutathione peroxidase and caspase-3, and suppression of 8-iso-Prostaglandin F2α generation in the retina. In summary, GTE and its catechin constituents are potent anti-oxidants that offer neuroprotection to the outer retinal degeneration after sodium iodate insult, among which EGCG is the most active constituent.


Catechin/pharmacology , Retinal Degeneration/drug therapy , Tea/chemistry , Administration, Oral , Animals , Antioxidants/pharmacology , Catechin/administration & dosage , Catechin/analogs & derivatives , Dinoprost/analogs & derivatives , Dinoprost/metabolism , Gene Expression Regulation/drug effects , Iodates/toxicity , Ophthalmoscopy/methods , Oxidative Stress/drug effects , Rats, Sprague-Dawley , Retinal Degeneration/chemically induced , Retinal Degeneration/pathology , Retinal Pigment Epithelium/drug effects , Retinal Pigment Epithelium/pathology
16.
J Nutr Biochem ; 26(11): 1357-67, 2015 Nov.
Article En | MEDLINE | ID: mdl-26362107

Green tea extract (GTE) exerts antioxidative activities in ocular tissues of rats, but high levels of (-)-epigallocatechin gallate (EGCG) can induce oxidative stress. In this study, pharmacokinetics, diurnal variation of oxidative status, antioxidation and transcription factors changes in ocular tissues of rats were investigated. Rats were fed intragastrically with GTE and catechin mixtures containing different amounts of EGCG. Plasma and various ocular tissues were taken for pharmacokinetic analysis, oxidation marker testings and gene expression assays. Effects of EGCG on ocular oxidation status were assessed by 8-isoprostane level and reduced/oxidized glutathione ratio. Oxidation, inflammation and apoptosis regulations in retina were evaluated by real-time polymerase chain reaction. Epicatechin, epigallocatechin and EGCG were dominant in various ocular tissues except vitreous humor, where gallocatechin was predominant. Diurnal variation of oxidative status was found in some compartments. GTE caused oxidative stress increase in the plasma, aqueous humor, vitreous humor, cornea and retina but decrease in the lens and choroid-sclera. Catechins mixture containing half dose of EGCG lowered 8-isoprostane in the retina and lens. GTE treatment induced superoxide dismutase 1 and glutathione peroxidase-3 expressions but suppressed catalase in the retina. Our results reveal pro-oxidation of GTE with high EGCG content to the ocular tissues. Optimal EGCG level is needed for protection.


Apoptosis/genetics , Catechin/analogs & derivatives , Endophthalmitis/genetics , Tea/chemistry , Animals , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Antioxidants/pharmacology , Apoptosis/drug effects , Catechin/blood , Catechin/pharmacokinetics , Catechin/pharmacology , Dose-Response Relationship, Drug , Endophthalmitis/diet therapy , Eye/drug effects , Eye/physiopathology , Female , Gene Expression Regulation/drug effects , Oxidative Stress/drug effects , Plant Extracts/chemistry , Rats, Sprague-Dawley , Vitreous Body/drug effects
17.
Proc Natl Acad Sci U S A ; 111(51): 18303-8, 2014 Dec 23.
Article En | MEDLINE | ID: mdl-25489106

Disruptions in immunity and occurrence of inflammation cause many eye diseases. The growth hormone-releasing hormone-growth hormone-insulin-like growth factor-1 (GHRH-GH-IGF1) axis exerts regulatory effects on the immune system. Its involvement in ocular inflammation remains to be investigated. Here we studied this signaling in endotoxin-induced uveitis (EIU) generated by LPS. The increase in GHRH receptor (GHRH-R) protein levels was parallel to the increase in mRNA levels of pituitary-specific transcription factor-1, GHRH-R splice variant 1, GHRH, and GH following LPS insult. Elevation of GHRH-R and GH receptor was localized on the epithelium of the iris and ciliary body, and GHRH-R was confined to the infiltrating macrophages and leukocytes in aqueous humor but not to those in stroma. Treatment with GHRH-R antagonist decreased LPS-stimulated surges of GH and IGF1 in aqueous humor and alleviated inflammation by reducing the infiltration of macrophages and leukocytes and the production of TNF-α, IL-1ß, and monocyte chemotactic protein-1. Our results indicate that inflammation in the iris and ciliary body involves the activation of GHRH signaling, which affects the recruitment of immune cells and the production of proinflammatory mediators that contribute to EIU pathogenesis. Moreover, the results suggest that GHRH-R antagonists are potential therapeutic agents for the treatment of acute ocular inflammation.


Growth Hormone-Releasing Hormone/therapeutic use , Receptors, Neuropeptide/antagonists & inhibitors , Receptors, Pituitary Hormone-Regulating Hormone/antagonists & inhibitors , Sermorelin/analogs & derivatives , Uveitis/prevention & control , Animals , Enzyme-Linked Immunosorbent Assay , Growth Hormone/blood , Insulin-Like Growth Factor I/metabolism , Rats , Rats, Sprague-Dawley , Sermorelin/therapeutic use
18.
PLoS One ; 9(8): e103995, 2014.
Article En | MEDLINE | ID: mdl-25093862

Green tea extract (GTE) ingested by rats exerted anti-oxidative activities in various ocular tissues as shown in our previous studies. The present work investigated anti-inflammatory effects of GTE on endotoxin-induced uveitis (EIU). EIU was generated in adult rats by a footpad injection of 1 mg/kg lipopolysaccharide (LPS). Oral administration of GTE (550 mg/kg) was given one, two or four times after LPS injection. Twenty-four hours later, LPS produced severe hyperemia and edema in the iris. Immunocytochemical examinations showed an accumulation of infiltrating cells in the aqueous humor that were immunopositive for cluster of differentiation 43 (CD43) and CD68, markers for leucocytes and macrophages, respectively. Analyses of the aqueous humor showed an increase in pro-inflammatory mediators including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1). GTE treatments improved the clinical manifestations and reduced infiltrating cells and protein exudation in the aqueous humor, which were not observed under half dose of GTE (275 mg/kg). The number of CD68 positive macrophages residing in the iris and ciliary was also reduced. GTE suppressed production of TNF-α, IL-6 and MCP-1 in the aqueous humor, which was associated with a down-regulation of LPS receptor complex subunits, Toll-like receptor 4 (TLR-4) and CD14, and suppression of nuclear factor-kappa Bp65 (NF-κBp65) in the iris and ciliary body. Our findings show that GTE is a potent anti-inflammatory agent against the inflammation of EIU, and suggest a potential use in treatment of acute uveitis.


Plant Extracts/pharmacology , Tea , Uveitis/drug therapy , Animals , Aqueous Humor/cytology , Aqueous Humor/immunology , Catechin/analogs & derivatives , Catechin/pharmacology , Disease Models, Animal , Endotoxins , Inflammation/chemically induced , Inflammation/drug therapy , Lipopolysaccharides , Neutrophil Infiltration , Rats , Rats, Sprague-Dawley , Tea/chemistry , Uveitis/chemically induced
19.
Chem Commun (Camb) ; 49(17): 1699-701, 2013 Feb 28.
Article En | MEDLINE | ID: mdl-23212209

Two MOF-74 analogs with OH groups on 1D channel surfaces have been synthesized through multi-component self-assembly at room temperature. Their guest-free forms demonstrate a potential luminescent probe or sensor for small molecules, and OH-MOF-74 (2a) also showed exceptional fluorescence quenching and enhancement behavior for different types of aromatic molecules.


Metals/chemistry , Organic Chemicals/chemistry , Organometallic Compounds/chemistry , Crystallography, X-Ray , Fluorescent Dyes/chemistry , Molecular Conformation , Solvents/chemistry , Spectrophotometry, Ultraviolet
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