Abstract
Patients with neurodegenerative diseases such as retinitis pigmentosa (RP) may engage in maladaptive coping behaviors, including alcohol misuse, which can aggravate disease progression. Neuroinflammation, a hallmark of RP, is largely driven by microglial activation and amplified when cells are primed by oxidative stress. Store-operated calcium entry (SOCE), primarily mediated by Orai1 channels, regulates microglial metabolism and inflammatory signaling. Here, we tested whether ethanol (EtOH) exacerbates RP-related neuroinflammation through SOCE-dependent mechanisms and whether 2-aminoethoxydiphenyl borate (2-APB) mitigates these effects. In mixed retinal cultures, a “double-hit” (oxidative stress + EtOH) triggered pronounced microglial activation, neuronal loss, and altered cytokine expression and correlation patterns, assessed by multiplex bead assays and hierarchical clustering analysis. Indeed, 2-APB restored ramified morphology and improved neuronal survival. Conditioned medium experiments revealed that both microglia and Müller cells responded to the double-hit, but only microglia were sensitive to SOCE inhibition. In vivo, subretinal delivery of EtOH and 2-APB in rd1 mice, a genetic model of RP, altered microglial morphology and reduced pro-inflammatory cytokine levels without affecting photoreceptor density. Notably, in situ assessment of CD86/CD206 showed no change in expression, indicating that microglial activation in vivo is better captured by morphological and cytokine-network alterations than by classical surface markers. These findings show that alcohol misuse amplifies retinal neuroinflammation in RP via calcium-dependent mechanisms and identify SOCE as a therapeutic target for limiting damage from systemic comorbidities in retinal degeneration.
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The datasets generated and/or analyzed during the current study are available from the corresponding author upon reasonable request.
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The authors acknowledge the Multiuser Center Facility (CEM) at UFABC.
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AHK is grateful for grants from Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP, Brazil, #2020/11667-0), Universidade Federal do ABC (UFABC, Brazil), and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, Brazil, 315372/2021-4). The following authors were recipients of fellowships from FAPESP: THLV (#2021/11969-9 and #2024/00828-3), GBS (#2021/14227-3), and GMB (#2024/10858-7). The following authors were recipients of fellowships from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, Brazil): MIM (Finance Code 001, #88887.597402/2021-00). The funders had no role in study design, data collection and analysis, decision to publish, or manuscript preparation.
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Conceived and designed the research: THLV and AHK. Performed experiments: THLV, BAM, GBS, GMB, and WS. Acquired, analyzed, or interpreted data: THLV, MIM, BAM, GBS, GMB, WS, and AHK. Wrote the manuscript: THLV and AHK. Revised the manuscript: THLV, MIM, and AHK.
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Lima-Vasconcellos, T.H.d., Menezes, B.d.A., Móvio, M.I. et al. Store-operated calcium entry drives alcohol-exacerbated neuroinflammation in retinal degeneration. Cell Death Discov. (2026). https://doi.org/10.1038/s41420-026-03074-2
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DOI: https://doi.org/10.1038/s41420-026-03074-2


