Analysis of the epidemiological burden of age-related macular degeneration in China based on the data of global burden of disease. / 基于GBDæ•°æ®åº“ä¸­å›½å¹´é¾„ç›¸å ³æ€§é»„æ–‘å˜æ€§æµè¡Œç— å­¦è´Ÿæ‹ åˆ†æž.

OBJECTIVES: Age-related macular degeneration (AMD) is one of the 3 major eye diseases recognized by WHO to prevent blindness, and which is the main cause of irreversible visual impairment in the elderly. This study aims to analyze the disease epidemiological burden, and provide a theoretical foundation for the prevention and control of AMD in China based on the data in global burden of disease (GBD) 2019. METHODS: The prevalent cases/prevalence, disability-adjusted life year (DALYs)/DALY rate of AMD and socio-demographic index (SDI) for global and China were searched from the GBD 2019 database to analyze the epidemiological trend, age-period-gender trend of AMD in China from 1990 to 2019, and to evaluate the relations between the prevalence and SDI. RESULTS: In 2019, the prevalence of AMD in China was at a high level in the world, and the number of prevalent cases were 1.93 times of that in 1990. The prevalence and DALY rates continued to rise. The age trend of AMD in China was high at the middle of the age stages and low at the two ends, and which was higher in the female than in the male. With the increase of SDI, the prevalence of AMD was increased linearly. CONCLUSIONS: The disease burden of AMD in China is increased significantly and is positively correlated with the social development from 1990 to 2019. It is of great significance to study the relationship between epidemilolgical data of AMD and social development level for diagnosis treatment and policy of AMD.

MiR-423-5p activated by E2F1 promotes neovascularization in diabetic retinopathy by targeting HIPK2.

BACKGROUND: Diabetic retinopathy (DR) is a diabetic complication and the primary cause of blindness in the world. However, the treatments of DR are challenging given its complicated pathogenesis. Here, we investigated the molecular mechanisms of DR by focusing on the function of E2F1/miR-423-5p/HIPK2/HIF1α/VEGF axis. METHODS: Cultured retinal endothelial cells (hRMECs, hRECs) were treated with 25 mM glucose to mimic the high glucose-induced DR in vitro. Streptozotocin (STZ) was injected into mice to induce DR in mice. qRT-PCR, western blotting, immunohistochemistry, and ELISA were employed to measure levels of E2F1, miR-423-5p, HIPK2, HIF1α, and VEGF. H&E staining was utilized to examine retinal neovascularization. CCK-8 assay, transwell assay, and vascular tube formation assay were used to assess the cell viability, migration, and angiogenesis. Dual luciferase assay was performed to validate interactions between E2F1 and miR-423-5p, miR-423-5p and HIPK2. RESULTS: HG treatment increased the cell viability, migration, and angiogenesis accompanied by upregulation of E2F1, miR-423-5p, HIF1α, and VEGF levels, but reduction in HIPK2 expression. Knockdown of E2F1 or miR-423-5p suppressed the HG-induced increases in cell viability, migration, and angiogenesis. E2F1 transcriptionally activated miR-423-5p expression and miR-423-5p mimics blocked the effects of E2F1 knockdown on angiogenesis. Moreover, miR-423-5p directly targeted HIPK2 to disinhibit HIF1α/VEGF signaling. Knockdown of HIPK2 reversed the effects of miR-423-5p inhibitor on cell viability, migration, and angiogenesis. Knockdown of E2F1 suppressed neovascularization during DR in vivo. CONCLUSIONS: E2F1 activates miR-423-5p transcription during DR to promote angiogenesis via suppressing HIPK2 expression to disinhibit HIF1α/VEGF signaling. Strategies targeting E2F1/miR-423-5p/HIPK2 axis could be potentially used for DR treatment.

Receptor-selective interleukin-4 mutein attenuates laser-induced choroidal neovascularization through the regulation of macrophage polarization in mice.

Macrophage polarization has been recognized as an important inflammatory regulator in choroidal neovascularization (CNV). However, the mechanisms regulating macrophage activation and polarization, as well as their effects on angiogenesis and CNV, have not yet been elucidated. IL-4 is implicated in macrophage activation and exerts different functions in various diseases through several receptors. In the current study, the effect of IL-4 muteins on CNV was investigated in vivo. CNV was induced by laser coagulation in wild type mice. IL-4 muteins were recombined into adenoviruses and injected into mice via the tail vein. To evaluate CNV, fluorescein fundus angiography and optical coherence tomography were performed on day 7 after coagulation. Quantitative PCR, western blotting and immunofluorescence staining were used to assess the levels of inflammatory markers. AdIL-4/Q116E, an adenovirus-expressed recombinant IL-4 mutein, selectively activated macrophages, alleviated laser-induced CNV in mice with reduced expression of M2 macrophages and increased the expression of M1 macrophages. Furthermore, the expression of monocyte to macrophage differentiation-associated and delta-like 4 (Dll4) in CNV lesions was upregulated. Employing AdIL-4/Q116E, a IL-4RI-selective mutein, may serve as a new strategy for CNV therapy. Moreover, the results indicated that Dll4 signaling served an important role in the regulation of macrophage polarization.

Neuroprotective role of epigallocatechin-3-gallate in acute glaucoma via the nuclear factor-κB signalling pathway.

Glaucoma is a disease involving impaired visual function accompanied by degeneration and necrosis of the optic nerve. Epigallocatechin-3-gallate (EGCG) exerts a neuroprotective effect against the degeneration of retinal ganglion cells. However, whether EGCG can relieve glaucoma and the possible mechanisms remain unclear. In order to determine the function of EGCG in glaucoma, an acute glaucoma rat model was established. Optic neuropathology was examined by haematoxylin-eosin staining and immunofluorescence staining for class III-ß tubulin. The levels of inflammation-associated cytokines, such as interleukin (IL)-4, IL-6, TNF-α, IL-1ß, IL-13 and IFN-γ were measured by flow cytometry. T cell proliferation was assessed by the carboxyfluorescein diacetate succinimidyl ester method. Finally, the functional role of EGCG in glaucoma was explored. The levels of the inflammation-associated proteins p-IκBα and p-p65 were measured by western blot analysis. The results showed that optic nerve injury occurred, and elevated levels of the inflammatory cytokines IL-4, IL-6, TNF-α, IL-1ß, IL-13 and IFN-γ were observed in the rat model of acute glaucoma. In addition, an increased T lymphocyte proliferation rate and imbalance of Th1/Th2 cytokines were present in the models. Importantly, treatment with EGCG significantly alleviated optic nerve injury. At the molecular level, EGCG decreased the levels of inflammation-associated cytokines, decreased the proliferation rate of T lymphocyte cells, and repaired the imbalance of Th1/Th2 cytokines. Moreover, EGCG inhibited the increase in the phosphorylation of IκBα and p65 caused by modelling and thus suppressed the activation of the nuclear factor (NF)-κB signalling pathway. The findings of the present study indicate that EGCG could attenuate the symptoms of glaucoma and inhibit inflammatory responses by suppressing the NF-κB signalling pathway in a rat glaucoma model.

Astragalus Polysaccharide Regulates miR-182/Bcl-2 Axis to Relieve Metabolic Memory through Suppressing Mitochondrial Damage-Mediated Apoptosis in Retinal Pigment Epithelial Cells.

INTRODUCTION: Metabolic memory is one of the causes of diabetic retinopathy, and astragalus polysaccharide (APS) has great advantages in the treatment of diabetes. However, the effect of APS on metabolic memory remains to be investigated. METHODS: Retinal pigment epithelial cell line ARPE-19 and primary retinal pigment epithelial cells were used to verify the effect of APS on mitochondria damage and apoptosis induced by high glucose-induced metabolic memory. The relationship between miR-182 and Bcl-2 was confirmed by a luciferase activity assay. Western blotting and quantitative reverse-transcriptase polymerase chain reaction were conducted to investigate the changes in mitochondrial damage- and apoptosis-associated markers. The cell mitochondrial membrane potential was assessed by JC-1 fluorescence. Terminal deoxynucleotidyl transferase dUTP nick end labelling staining and flow cytometry assays were performed to determine the occurrence of apoptosis. RESULTS: Treatment with high glucose followed by normal glucose significantly upregulated the expression of miR-182 and downregulated the expression of its target Bcl-2, and APS treatment reversed the above effects. Additionally, APS treatment restored mitochondrial function and inhibited apoptosis in cells in a state of metabolic memory. The effects of APS against mitochondrial damage and apoptosis were partially inhibited after miR-182 overexpression. CONCLUSION: APS alleviated mitochondrial damage and apoptosis induced by metabolic memory by regulating the miR-182/Bcl-2 axis, which might serve as a new strategy for the treatment of diabetic retinopathy.

Impaired 26S Proteasome Assembly Precedes Neuronal Loss in Mutant UBQLN2 Rats.

Proteasomal dysfunction is known to be associated with amyotrophic lateral sclerosis and frontotemporal degeneration (ALS/FTD). Our previous reports have shown that a mutant form of ubiquilin-2 (UBQLN2) linked to ALS/FTD leads to neurodegeneration accompanied by accumulations of the proteasome subunit Rpt1 in transgenic rats, but the precise pathogenic mechanisms of how this mutation impairs the proteasome remains to be elucidated. Here, we reveal that this UBQLN2 mutation in rats disrupted the proteasome integrity prior to neurodegeneration, that it dissociated the 26S proteasome in vitro, and that its depletion did not affect 26S proteasome assembly. During both disease progression and in an age-dependent manner, we found that proteasome subunits were translocated to the nucleus, including both of the 20S core particles (PSMA1 and PSMB7) and the 19S regulatory particles (Rpt1 and Rpn1), suggesting that defective proteasome function may result from the proteasome-subunit mislocalization. Taken together, the present data demonstrate that impaired proteasome assembly is an early event in the pathogenesis of UBQLN2-associated neurodegeneration in mutant UBQLN2 rats.

Mutant UBQLN2P497H in motor neurons leads to ALS-like phenotypes and defective autophagy in rats.

Mutations in ubiquilin2 (UBQLN2) have been linked to abnormal protein aggregation in amyotrophic lateral sclerosis (ALS). The mechanisms underlying UBQLN2-related neurodegenerative diseases remain unclear. Using a tetracycline-regulated gene expression system, the ALS-linked UBQLN2P497H mutant was selectively expressed in either the spinal motor neurons or astrocytes in rats. We found that selectively expressing mutant UBQLN2P497H in the spinal motor neurons caused several core features of ALS, including the progressive degeneration of motor neurons, the denervation atrophy of skeletal muscles, and the abnormal protein accumulation. Furthermore, mutant UBQLN2P497H accumulation was associated with an age-dependent decrease in several core autophagy-related proteins. ALS-like phenotypes were not observed when mutant UBQLN2P497H was overexpressed in the astrocytes, however, even though the expression of the mutant UBQLN2P497H protein was higher in these rats. Our results suggest that selectively expressing mutant UBQLN2P497H in motor neurons is sufficient to trigger the development of ALS in rats. Our results further indicate that the compromised autophagy-lysosomal pathway plays a critical role in the pathogenesis of UBQLN2-related neurodegenerative diseases.

Viability of primary cultured retinal neurons in a hyperglycemic condition.

The retina of Wistar rats within 1-3 days of birth were dissociated into a retinal cell suspension using 0.05% trypsin digestion. The cell suspension was incubated in Dulbecco's modified Eagle's medium for 24 hours, followed by neurobasal medium for 5-7 days. Nissl staining showed that 79.86% of primary cultured retinal cells were positive and immunocytochemical staining showed that the purity of anti-neurofilament heavy chain antibody-positive cells was 71.53%, indicating that the primary culture system of rat retinal neurons was a reliable and stable cell system with neurons as the predominant cell type. The primary cultured retinal neurons were further treated with 0, 5.5, 15, 25, and 35 mM glucose for 24, 48, and 72 hours. The thiazolyl blue tetrazolium bromide test and flow cytometry showed that with increasing glucose concentration and treatment duration, the viability of retinal neurons was reduced, and apoptosis increased. In particular, 35 mM glucose exhibited the most significant effect at 72 hours. Thus, rat retinal neurons treated with 35 mM glucose for 72 hours can be used to simulate a neuronal model of diabetic retinopathy.