bims-mideyd 2025-11-09 papers

Cell Signal. 2025 Nov 01. pii: S0898-6568(25)00621-7. [Epub ahead of print]137 112206

PYGM downregulates necroptosis signaling to attenuate sodium iodate-induced RPE cell degeneration.

Yaqi Cheng, Simin Gu, Huan Yu, Jiayi Jin, Huanhuan Cheng, Huini Zhang, Jiayi Lin, Meng Li, Haocheng Zhu, Tao Wang, Qunai Huang, Yingjie Liu, Pengjie Yue, Weihua Li, Shiqi Ling.

BACKGROUND: Age-related macular degeneration (AMD) causes incurable vision loss in elderly individuals, and there is currently only a rarely effective treatment for dry AMD. Necroptosis is attracting increasing attention in the context of AMD. This study aimed to elucidate the mechanisms underlying the induction of abnormal necroptosis in AMD.
METHODS: Sodium iodate (SI) was used to establish in vitro and in vivo retinal pigment epithelium cell (RPE) degeneration models and to simulate dry AMD-like conditions. Phenotypes and classic necroptosis markers were identified. RNA-seq was performed on the retinas of RPE-degeneration mice and combined with the GSE29801 microarray data of human AMD retinal samples to identify the key genes regulating necroptosis. Key genes were overexpressed both in vivo and in vitro to further validate their function in necroptosis and RPE degeneration.
RESULTS: Necroptosis phenotypes and the expression of the necroptosis markers RIPK1, RIPK3, and MLKL were upregulated in both SI-treated ARPE-19 cells and the RPE layer of mice. Transcriptome data from SI-treated mice and patients with AMD revealed that the reduced expression of PYGM is implicated in the regulation of necroptosis. PYGM overexpression in RPE cells and mouse retinas alleviated SI-induced RPE degeneration.
CONCLUSIONS: This study confirmed that PYGM attenuates necroptosis in cellular and animal models resembling dry AMD, providing a new perspective on exploring novel AMD treatment targets.

Keywords: Age-related macular degeneration; Necroptosis; PYGM

DOI: https://doi.org/10.1016/j.cellsig.2025.112206

J Vis Exp. 2025 Oct 17.

Alu RNA-transfected Primary Mouse Retinal Pigment Epithelium: A Pathologically Relevant In Vitro Model for Age-related Macular Degeneration.

Xinyue Hu, Yuhao Tang, Haoliang Zhang, Zilin Wang, Junran Sun.

Age-related macular degeneration (AMD), particularly non-exudative AMD, requires experimental models that better replicate human pathology. Current in vivo models remain technically demanding and time-intensive, whereas conventional in vitro systems fail to recapitulate disease-specific pathological triggers. Here, we present a method to establish a retinal pigment epithelial (RPE) degeneration model using primary mouse RPE cells transfected with Alu RNA, a retrotransposon directly implicated in geographic atrophy pathology. This protocol details the enzymatic isolation of primary mouse RPE cells, followed by Alu RNA transfection to induce RPE degeneration. Validation integrates morphological (hexagonal architecture), functional (polarity loss and mouse protein ZO-1 disruption), and molecular analysis (quantitative PCR). As a result, we observed multifactorial changes triggered by Alu RNA transfection: inflammatory cytokine secretion (mouse genes Ifn-β, Il-6, Tnf-α; p < 0.05) and cellular senescence (mouse genes p21 and p53 upregulation; p < 0.05). Compared to traditional acute stress models, this system recapitulates chronic inflammatory-degenerative cascades of AMD through standardized techniques, ensuring reproducibility. By combining aspects of simplified in vitro assays and complex in vivo models, this approach could serve as a preliminary platform for exploring retrotransposon-driven mechanisms and screening potential therapeutic candidates.

DOI: https://doi.org/10.3791/68570

Front Physiol. 2025 ;16 1641653

RARRES1 attenuates H2O2-induced RPE cell injury and inhibits choroidal neovascularization.

Yimeng Li, Caixia Wang, Tao Deng, Xuejing Li, Renhao Xu, Qingli Shang.

Introduction: Neovascular age-related macular degeneration (nAMD) is a leading cause of vision loss in the elderly, yet its underlying molecular mechanisms remain incompletely understood, and novel biomarkers and therapeutic targets are urgently needed. This study aimed to identify and functionally characterize potential biomarkers and therapeutic candidates for nAMD, with a focus on retinoic acid receptor responder protein 1 (RARRES1).
Methods: Tandem mass tag (TMT)-based proteomic analysis was performed on aqueous humor samples from patients with nAMD and age-related cataracts. RARRES1 expression was examined in aqueous humor, laser-induced choroidal neovascularization (CNV) model mice, and human ARPE-19 cells exposed to H2O2. Functional studies assessed the effects of RARRES1 on oxidative stress, cell death, inflammatory and angiogenic factor expression, and signaling pathways in ARPE-19 cells. Its effects on proliferation, migration, and tube formation were tested in HUVECs. In vivo, a RARRES1-overexpressing AAV2 vector was injected intraocularly into CNV model mice, and lesion size and vascular leakage were evaluated using fundus fluorescein angiography, hematoxylin and eosin staining, and isolectin B-4 fluorescence staining.
Results: RARRES1 was significantly reduced in the aqueous humor of nAMD patients, in CNV model mice, and in H2O2-treated ARPE-19 cells. Overexpression of RARRES1 in ARPE-19 cells mitigated oxidative stress-induced damage, suppressed inflammatory and angiogenic factor expression, inhibited JNK phosphorylation, and increased Sirtuin 1 and Nrf2 expression. In HUVECs, RARRES1 reduced proliferation, migration, and tube formation. In vivo, intraocular delivery of RARRES1 significantly reduced CNV lesion size and vascular leakage.
Conclusion: RARRES1 protects retinal pigment epithelial cells from oxidative stress, inhibits choroidal neovascularization, and modulates inflammatory and angiogenic pathways. These findings identify RARRES1 as a potential biomarker and therapeutic target for nAMD.

Keywords: RARRES1; choroidal neovascularization; neovascular age-related macular degeneration; oxidative stress; viability

DOI: https://doi.org/10.3389/fphys.2025.1641653

Exp Cell Res. 2025 Oct 30. pii: S0014-4827(25)00413-6. [Epub ahead of print] 114813

The RPE-derived NF-κB/HO-1/MCP-1 pathway mediated Microglia Recruitment Involved in the Outer Blood-Retinal Barrier Breakdown in Experimental Diabetic Retinopathy.

Yiyang Shu, Dandan Liu, Hai Xie, Chaoyang Zhang, Yanlong Bi, Jingfa Zhang.

PURPOSE: To investigate the mechanisms underlying the microglia recruitment and its causal role in the breakdown of the outer blood-retinal barrier (oBRB) in diabetic retinopathy (DR).
METHODS: The Sprague-Dawley rats were adopted to establish diabetic model by intraperitoneal injection of streptozotocin. Twelve weeks later, the retinal pigment epithelium (RPE)-choroid complexes and retinal paraffin sections were examined with immunofluorescence. RNA-sequencing was performed on glyoxal-treated ARPE-19 cells, followed by bioinformatic analysis to identify significant genes and pathways. Transwell assays were employed to establish the co-culture system and investigate the interactions between ARPE-19 and BV2 microglial cells. The results were further validated by the inhibitor or siRNAs targeting NF-κB, HO-1, and MCP-1.
RESULTS: In 12-week diabetic rat retinas, microglia cells were observed to accumulate in the vicinity of the RPE cells, accompanied by the disruption of ZO-1. The expressions of ZO-1 and occludin remained largely unchanged in ARPE-19 cells when treated with glyoxal alone. However, when co-cultured with BV2 microglial cells, the expression levels of ZO-1 and occludin in glyoxal-treated ARPE-19 cells were significantly decreased, which were effectively prevented by siMCP-1. Mechanistically, RNA-sequencing analysis revealed that the activation of the NF-κB/HO-1/MCP-1 pathway in glyoxal-treated ARPE-19 cells significantly contributed to the recruitment of microglia. The above effects were reversed by BAY 11-7082, siHO-1 or siMCP-1.
CONCLUSION: Under diabetic condition, microglia are recruited by RPE cells via the NF-κB/HO-1/MCP-1 pathway, which subsequently result in the oBRB breakdown. This study provides a novel mechanistic insight for the interaction between microglia and RPE cells, and implies a potential therapeutic strategy for the treatment of DR.

Keywords: Diabetic retinopathy; Microglia; NF-κB/HO-1/MCP-1 pathway; Outer blood-retinal barrier; RPE

DOI: https://doi.org/10.1016/j.yexcr.2025.114813

PLoS One. 2025 ;20(11): e0335526

Effect of dopamine on TGF-β2 secretion by human retinal pigment epithelial cells and the underlying mechanism.

Jing Fan, Qiujin Zhang, Liu Zheng, Binbin Yang, He Jin, Tingyu Meng, Zhixiang Ding.

BACKGROUND: Dopamine is known to play a role in the development of myopia. In this study, we investigated the effect of dopamine (DA) on the secretion of transforming growth factor-β2 (TGF-β2) in human retinal pigment epithelial (RPE) cells. Additionally, we examined the effects of SCH23390 (D1 receptor antagonist) and sulpiride (D2 receptor antagonist) on TGF-β2 levels in ARPE-19 cells to elucidate the underlying mechanism of DA in myopia development.
METHODS: Human RPE cells were cultured with or without different concentrations of DA, SCH23390, or sulpiride. Cell proliferation was examined using the CCK-8 assay. Cell migration was assessed by performing a cell scratch (wound healing) assay. The expression of TGF-β2 was evaluated at the mRNA and protein levels by real-time PCR and western blotting, respectively. Furthermore, the secretion of TGF-β2 into the ARPE-19 cell supernatant was quantified using ELISA.
RESULTS: Treatment with 20 μg/mL of DA significantly increased (P < 0.05) the mRNA and protein expression levels of DRD1, DRD2, YAP, and TEAD and decreased TGF-β2 levels compared with that in control group. However, treatment with 24 μg/mL of SCH23390 for 24 h significantly decreased (P < 0.05) DRD1 and TGF-β2 mRNA expression and increased DRD2, YAP, and TEAD mRNA expression in ARPE-19 cells compared with that in the control group. Additionally, the protein expression levels of TGF-β2, YAP, TEAD, and SMAD7 were consistent with the mRNA levels. Notably, treatment with sulpiride (14 μg/mL) increased (P < 0.05) DRD1 and TGF-β2 expression and decreased DRD2, YAP, and TEAD expression in the cells at both the mRNA and protein levels compared with that in the control group.
CONCLUSIONS: Our findings suggest that dopamine suppresses TGF-β2 secretion in human retinal pigment epithelial cells primarily through activation of D2 receptors, which appears to involve the YAP-TGF-β-Smad signaling pathway. This regulatory mechanism may contribute to the control of scleral remodeling and thus influence the development of myopia.

DOI: https://doi.org/10.1371/journal.pone.0335526