Innate immune responsive inflammation in development of progressive myopia.

PURPOSE: Inflammation has been implicated for development of myopia. It is not clear when inflammation is kicked in during the course of myopia, and what characteristics of the inflammation. In this study, we tested for cytokines from aqueous humour of eyes with wide spectrum of refractive status for profiling the inflammation. METHODS: Aqueous humour of 142 patient eyes were tested for soluble intercellular adhesion molecule 1 (sICAM-1), monocyte chemoattractant protein-1 (MCP-1), and transforming growth factor-beta 2 (TGF-ß2) using an enzyme-linked immunosorbent assay (ELISA). Eye globe axial length of these patients ranged from emmetropia to high myopia. RESULTS: Of 142 patients, an average axial length is 25.51 ± 3.31 mm, with a range of 21.56-34.37 mm. There are 36 cases in lower 25 percentile, 37 cases in upper 25 percentile, and 69 case in the middle 50 percentile. sICAM-1 and MCP-1 were significantly higher in the eyes with staphyloma (407.48 pg/mL, 312.31 pg/mL, n = 33) or macular schisis (445.86 pg/mL,345.33 pg/mL, n = 19) than that in the eyes without these changes (206.44 pg/mL, 244.76 pg/mL, n = 107). All three cytokines level was significantly associated with eye globe axial in a positive mode while adjusting for the age and sex. Strength of the association was the greatest for sICAM-1 and the weakest for TGF- ß2. MCP-1 was in between. CONCLUSION: sICAM-1 and MCP-1 in ocular fluid may be indicative biomarkers for progressive high myopia and the underneath autoimmune inflammation. sICAM-1 may be used as a monitoring biomarker for development of pathologic myopia.

Adenosine A2A receptor antagonist KW6002 protects against A53T mutant alpha-synuclein-induced brain damage and neuronal apoptosis in Parkinson's disease mice by restoring autophagic flux.

BACKGROUND: Protein misfolding and inclusion body aggregation caused by α-Syn mutations in the brain often cause neurodegeneration and cognitive impairment, among which the A53T point mutation is more common. Inhibition of adenosine A2A receptor (A2AR) can alleviate the pathological symptoms of brain dysfunction caused by A53T-α-Syn protofibrils, but the mechanism of action is still unclear. AIM: This studies aimed to investigate the potential therapeutic role of the A2AR inhibitor KW6002 in a mouse model of brain synucleinopathy. METHODS: A53T-α-Syn fibre precursor cell nuclear protein was injected into the bilateral prefrontal cortex of mice to establish a synucleinopathy animal model, and the A2AR inhibitor KW6002 (5 mg/kg) was injected intraperitoneally to intervene. RESULT: The intracerebral injection of A53T-α-Syn protofibrils triggers the formation of inclusion bodies in the brain, leading to astrocyte activation, an increased number of apoptotic cells, and suppression of autophagic flux. The administration of KW6002 significantly reversed these phenomena. In vitro experiments revealed that A53T-α-Syn protofibrils inhibited HT-22 autophagy in mouse hippocampal neuronal cells, whereas KW6002 increased cellular autophagic flux, upregulated the expression of LAMP2A and Hsc70 proteins and inhibited the expression of SQSTM1 protein. The present study suggests that KW6002 reduces the level of α-Syn phosphorylation by inhibiting A2AR protein, at the same time, enhances the autophagic flux of neuronal cells, resulting in the degradation of A53T-α-Syn protofibrils and thus reducing the neuronal toxicity and apoptosis induced by A53T-α-Syn protofibrils. CONCLUSION: KW6002 has a significant protective effect on neuronal injury induced by A53T-α-Syn.

miR-204 suppresses uveal melanoma cell migration and invasion through negative regulation of RAB22A.

Uveal melanoma (UM), a frequently seen adulthood primary ocular malignancy, shows high aggressiveness. Accumulating studies have revealed the crucial effects of microRNAs (miRNAs) on tumorigenesis and development in various human tumors. miR-204, the cancer-associated miRNA, shows dysregulation and is related to several human malignancies, but its effect on UM remains unknown. The present work focused on exploring miR-204's effect on UM and elucidating its possible molecular mechanisms. According to our results, miR-204 expression markedly increased within both UM tissues and cell lines. As revealed by functional analysis, miR-204 suppressed UM cell invasion and migration. Besides, RAB22A expression decreased through directly binding miR-204 into the corresponding 3' untranslated region (3'UTR) in UM cells. Furthermore, the RAB22A mRNA level increased, which was negatively related to the miR-204 level within UM samples. As revealed by mechanical research, miR-204 exerted its inhibition on the invasion and migration of UM cells via RAB22A. Taken together, this study suggested the tumor-suppressing effect of miR-204 on UM through down-regulating RAB22A. Thus, miR-204 may serve as the new anti-UM therapeutic target.

The protective effect of URP20 on ocular Staphylococcus aureus and Escherichia coli infection in rats.

BACKGROUND: Infectious keratitis, a medical emergency with acute and rapid disease progression may lead to severe visual impairment and even blindness. Herein, an antimicrobial polypeptide from Crassostrea hongkongensis, named URP20, was evaluated for its therapeutic efficacy against keratitis caused by Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) infection in rats, respectively. METHODS: A needle was used to scratch the surface of the eyeballs of rats and infect them with S. aureus and E.coli to construct a keratitis model. The two models were treated by giving 100 µL 100 µM URP20 drops. Positive drugs for S. aureus and E. coli infection were cefazolin eye drops and tobramycin eye drops, respectively. For the curative effect, the formation of blood vessels in the fundus was observed by a slit lamp (the third day). At the end of the experiment, the condition of the injured eye was photographed by cobalt blue light using 5 µL of 1% sodium fluorescein. The pathological damage to corneal tissues was assessed using hematoxylin-eosin staining, and the expression level of vascular endothelial growth factor (VEGF) was detected by immunohistochemistry. RESULTS: URP20 alleviated the symptoms of corneal neovascularization as observed by slit lamp and cobalt blue lamp. The activity of S. aureus and E.coli is inhibited by URP20 to protect corneal epithelial cells and reduce corneal stromal bacterial invasion. It also prevented corneal thickening and inhibited neovascularization by reducing VEGF expression at the cornea. CONCLUSION: URP20 can effectively inhibit keratitis caused by E.coli as well as S. aureus in rats, as reflected by the inhibition of corneal neovascularization and the reduction in bacterial damage to the cornea.

Conjunctiva Resident γδ T Cells Expressed High Level of IL-17A and Promoted the Severity of Dry Eye.

Purpose: Conjunctival inflammation promotes ocular surface disorders in dry eye disease (DED). Here we identified γδ T cells as the predominant source of IL-17A in the murine conjunctiva and assessed their contribution to the pathogenesis of DED. Methods: We enrolled 22 patients with DED, and analyzed the proportion of γδ T cells in the conjunctival epithelial samples by flow cytometry. Adult C57Bl/6 wild-type and TCRδ-/- mice were used to induce DED models to investigate the role of γδ T cells. The characteristics of immune cell infiltration and the expression of immune-related cytokines or markers in mouse conjunctiva were analyzed by flow cytometry, Western blot, and quantitative polymerase chain reaction. Results: The proportion of γδ T cells in the human DED conjunctiva is significantly higher in patients with severe corneal epithelial defects than in mild ones, which is consistently observed in the murine DED model. Further, a high level of IL-17A but not IFN-γ is detected in the conjunctiva of mice. The increased murine IL-17A-producing cells on the conjunctiva are identified as γδ T cells predominantly and Th17 cells to a lesser extent. Ablation of γδ T cells by antibody depletion or genetic deletion of TCRδ alleviates ocular surface damage in the murine DED model. Conclusions: Our studies evaluate human and experimental murine DED for evidence of γδ T-cell-mediated inflammation and highlight a potential therapeutic synergy by targeting IL-17 and γδ T cells in DED treatment.

The Connection between High Myopia Patients and MiR-708a or MiR-148 Expression Levels in Aqueous Studies of Visual Acuity.

Myopia goes far beyond the inconvenience it brings. It is a prevailing and vision-threatening eye disease, especially in Asia. Aberrantly expressed miR-708a and miR-148 are critical for accurate diagnosis, good prognosis, and precise response prediction of myopia. In this paper, we aim to examine the potential contributions of miR-708a, miR-148a, and PAX6 to high myopia (HM). First, aqueous samples were taken from 25 exclusively HM eyes and 25 exclusively cataract eyes. For next-generation sequencing and bioinformatics analysis, RNA from sample 30one was used. Twenty more samples were used for RT-qPCR. 341 miRNAs in total were found in HM eyes; 249 mature miRNAs and 17 new miRNAs showed differential expression. The expression of hsa-miR-127-3p, hsa-let-7i-5p, and hsa-miR-98-5p was identified using RT-qPCR. MiR-708a and miR-148, which may be linked to the development of myopia and serve as possible biomarkers, are notably highly expressed in atrial tissues of HM patients. Our findings may help deepen the understanding of the mechanisms behind the high expression of miR-708a and miR-148 in atrial tissues of patients with HM.

Implication of inflammatory cytokines in the aqueous humour for management of macular diseases.

PURPOSE: To characterize profile of cytokines in aqueous humour of common macular diseases during intravitreal anti-VEGF therapy. METHODS: Aqueous humour from eyes with central retinal vein occlusion (CRVO), branch retinal vein occlusion (BRVO), diabetic macular oedema (DME), neovascular age-related macular degeneration (nAMD) or pathologic myopia associated choroidal neovascularization (pmCNV) was sampled prior to 1st (n = 144) and 2nd (n = 48) intravitreal anti-VEGF therapy. Cytokines including vascular endothelium growth factor (VEGF), intercellular adhesion molecule 1 (ICAM-1) and interleukin 6 (IL-6) were quantitated and analysed along with retinal thickness data by optical coherence tomography (OCT) across two intravitreal injections and five macular disease types. RESULTS: ICAM-1, IL-6 and VEGF are positively associated in the aqueous humour of naive eyes (r = 0.39-0.77, p = 0.018 to <0.0001). ICAM-1, VEGF and IL-6 were significantly higher in CRVO and DME while lowest in pmCNV (p < 0.0001). Reduction of central retinal thickness (CRT) as a favourable response to anti-VEGF therapy was in the order of CRVO, BRVO, DME and nAMD/pmCNV (p < 0.0001). The strongest predictor for favourable CRT reduction was baseline CRT (p < 0.0001) followed by baseline ICAM-1 (p = 0.04). After the 1st intravitreal anti-VEGF therapy, VEGF in aqueous humour lowered significantly but ICAM-1 and IL-6 levels remained unchanged. ICAM-1 was not predictive for CRT reduction following 2nd anti-VEGF therapy. CONCLUSION: Rate of cytokine production is disease-dependent and higher in CRVO and DME. Anatomical response to intravitreal anti-VEGF therapy is disease-specific and best in RVO patients. A combination therapy using both anti-VEGF and anti-inflammatory therapeutics may be superior to single anti-VEGF therapy, at least for RVO and DME.

Role of inflammatory factors in the effects of aflibercept or ranibizumab treatment for alleviating wet age-associated macular degeneration.

Aflibercept and ranibizumab are novel drugs for effectively treating wet age-associated macular degeneration (AMD). In the present study, the effect of aflibercept and ranibizumab on wet AMD was compared. A total of 80 AMD patients were intravitreously treated with aflibercept (2.0 mg/dose, 40 participants) or ranibizumab (0.3 mg/dose, 40 participants). The mean visual acuity and central subfield thickness (CTS) were determined at baseline and each follow-up visit (every 4 weeks). ELISA was used to detect the expression of transforming growth factor-ß1 (TGF-ß1), monocyte chemoattractant protein 1 (MCP-1) and interleukin 6 (IL-6). The primary outcome was the mean change in visual acuity letter score (VAS) and CTS at 1 year. The VAS was markedly improved by 13.1 in the aflibercept group and by 11.0 in the ranibizumab group. In a subgroup of patients with an initial VAS of <69, the mean improvement in the VAS was 17.7 in the aflibercept group and 13.2 in the ranibizumab group (P<0.01). The mean CTS was markedly decreased by 141 in the aflibercept group and by 134 in the ranibizumab group. In the subgroup of patients with an initial VAS of <69, the mean CTS was decreased by 171 in the aflibercept group and by 154 in the ranibizumab group (P<0.01). However, the change of VAS and CTS was similar between the ranibizumab and aflibercept groups when the initial VAS was ≥69. No significant differences in serious adverse events were identified between the aflibercept and ranibizumab groups. The levels of TGF-ß1, IL-6 and MCP-1 were decreased by the aflibercept and ranibizumab treatments. The decrease in the levels of the inflammatory factors was more obvious in patients with an initial VAS of <69 in comparison with that in patients with an initial VAS of ≥69. Negative correlations between the levels of TGF-ß1, MCP-1 and IL-6 and the mean change of VAS when patients were treated with aflibercept or ranibizumab were identified among all ages. Positive correlations between the levels of TGF-ß1, MCP-1 and IL-6 and the mean change of CTS were observed when the initial VAS of the patients was <69. In conclusion, the efficacy of aflibercept in treating patients with AMD was better than that of ranibizumab when the initial VAS of the patients was <69. The inhibition of inflammatory factors may be a secondary effect of aflibercept and ranibizumab treatment. The present study provides a useful reference for the clinical treatment of wet AMD (Chinese Clinical Trial Registry no. ChiCTR1800017782).

Inflammatory cytokines in highly myopic eyes.

Currently, myopic retinopathy is the most common irreversible blinding disease but its pathophysiology is not completely clear. A cross-sectional, observational study was conducted in a single center to analyze aqueous samples from highly myopic eyes (axial length >25 mm, n = 92) and ametropic or mild myopic eyes (n = 88) for inflammatory cytokines. Vascular endothelial growth factor (VEGF), Interleukin 6 (IL-6), and matrix metalloproteinase-2 (MMP-2) were measured using an enzyme-linked immunosorbent assay. IL-6 and MMP-2 were significantly higher in the highly myopic eyes than in the non-high myopic eyes (IL-6: 11.90 vs. 4.38 pg/mL, p < 0.0001; MMP-2: 13.10 vs. 8.82 ng/mL, p = 0.0003) while adjusting for age, gender, and intraocular pressure. There was a significant positive association between levels of IL-6 and MMP-2 in aqueous humor and the axial lengths of the eye globes (IL-6, ß = 0.065, p < 0.0001, n = 134; MMP-2, ß = 0.097, p < 0.0001, n = 131). Conversely, VEGF in aqueous humor was significantly lower in the highly myopic eyes than in the non-high myopic eyes (45.56 vs. 96.90 pg/mL, p < 0.0001, n = 153) while age, gender, and intraocular pressure were adjusted. The results suggest that low-grade intraocular inflammation may play an important role in the development and progression of high myopia and myopic retinopathy.

Inhibition of migration and invasion by berberine via inactivation of PI3K/Akt and p38 in human retinoblastoma cell line.

BACKGROUND: As a clinically important natural isoquinoline alkaloid, berberine has been reported to possess various pharmacological effects. OBJECTIVES: This study was aimed to investigate the effect of berberine on cell migration and invasion in human retinoblastoma (Rb) cells. MATERIAL AND METHODS: The cytotoxicity of berberine was estimated by 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay. After being stimulated with berberine under various concentrations, the cell migration and invasion were evaluated by transwell assay. Then, the expression levels of epithelial-mesenchymal transition (EMT) markers were determined by quantitative reverse transcription PCR (qRT-PCR) and western blot analysis. Furthermore, the phosphorylation levels of protein kinase B (Akt) and p38 were detected by western blot analysis. Finally, the effect of phosphatidylinositol-3-kinase (PI3K) and p38 inhibitors on cell migration and invasion was estimated by transwell assay. Untreated cells acted as control for all the experiments. RESULTS: The concentrations of berberine for further studies were controlled in a range of 0 to 100 µM. The cell migration and invasion were both suppressed by berberine in a dose-dependent manner compared to the control (p < 0.05 or p < 0.001). Berberine remarkably down-regulated expression of E-cadherin and up-regulated expression of vimentin and α-SMA compared to the control (p < 0.01 or p < 0.001). Furthermore, the phosphorylation levels of Akt and p38 were both down-regulated by berberine in comparison to the control. Furthermore, the addition of berberine accompanied by LY294002 or SB203580 significantly suppressed cell migration and invasion compared to the addition of berberine alone (p < 0.05). CONCLUSIONS: Berberine suppressed cell migration and invasion via inactivation of PI3K/Akt and p38.

Lysergic acid diethylamide causes photoreceptor cell damage through inducing inflammatory response and oxidative stress.

Lysergic acid diethylamide (LSD), a classical hallucinogen, was used as a popular and notorious substance of abuse in various parts of the world. Its abuse could result in long-lasting abnormalities in retina and little is known about the exact mechanism. This study was to investigate the effect of LSD on macrophage activation state at non-toxic concentration and its resultant toxicity to photoreceptor cells. Results showed that cytotoxicity was caused by LSD on 661 W cells after co-culturing with RAW264.7 cells. Treatment with LSD-induced RAW264.7 cells to the M1 phenotype, releasing more pro-inflammatory cytokines, and increasing the M1-related gene expression. Moreover, after co-culturing with RAW264.7 cells, significant oxidative stress in 661 W cells treated with LSD was observed, by increasing the level of malondialdehyde (MDA) and reactive oxygen species (ROS), and decreasing the level of glutathione (GSH) and the activity of superoxide dismutase (SOD). Our study demonstrated that LSD caused photoreceptor cell damage by inducing inflammatory response and resultant oxidative stress, providing the scientific rationale for the toxicity of LSD to retina.

Metformin inhibits development of diabetic retinopathy through inducing alternative splicing of VEGF-A.

Previous studies have shown that metformin, an AMP-activated protein kinase activator widely prescribed for type 2 diabetes, is especially beneficial in cases of diabetic retinopathy (DR) with undetermined mechanisms. Here, we used a streptozotocin-induced diabetes model in mice to study the effects of metformin on the development of DR. We found that 10 weeks after STZ treatment, DR was induced in STZ-treated mice, regardless treatment of metformin. However, metformin alleviated the DR, seemingly through attenuating the retina neovascularization. The total vascular endothelial cell growth factor A (VEGF-A) in eyes was not altered by metformin, but the phosphorylation of the VEGF receptor 2 (VEGFR2) was decreased, which inhibited VEGF signaling. Further analysis showed that metformin may induce VEGF-A mRNA splicing to VEGF120 isoform to reduce its activation of the VEGFR2. These findings are critical for generating novel medicine for DR treatment.

Safety in Treating Primary Acute Angle-closure Glaucoma under High Intraocular Pressure by Compound Trabeculectomy.

In clinical practice, Primary Acute Angle-closure Glaucoma (APACG) is a common disease with an increasing incidence rate and blind rate, and has attracted attention of medical researchers. When a patient suffers both primary acute glaucoma and high tension glaucoma, drug therapy can achieve limited efficacy, and operative treatment is necessary on this occasion. This research mainly explored the safety in treating high tension APACG by compound trabeculectomy, and observed the clinical treatment effect and incident rate of postoperative complications after compound trabeculectomy. The compound trabeculectomy can effectively control the intraocular pressure and decrease the incident rate of postoperative complications, accelerating the rehabilitation of patients.