{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T21:00:04Z","timestamp":1790802004802,"version":"4.1.0"},"reference-count":12,"publisher":"Springer Science and Business Media LLC","issue":"12","license":[{"start":{"date-parts":[[2025,10,2]],"date-time":"2025-10-02T00:00:00Z","timestamp":1759363200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2025,10,2]],"date-time":"2025-10-02T00:00:00Z","timestamp":1759363200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Northern Ireland Health and Social Care R&D Division","award":["STL\/4748\/13"],"award-info":[{"award-number":["STL\/4748\/13"]}]},{"name":"Randerson Foundation"},{"DOI":"10.13039\/501100000265","name":"Medical Research Council","doi-asserted-by":"publisher","award":["MC_PC_15026"],"award-info":[{"award-number":["MC_PC_15026"]}],"id":[{"id":"10.13039\/501100000265","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Diabetologia"],"published-print":{"date-parts":[[2025,12]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Aims\/hypothesis<\/jats:title>\n                    <jats:p>This study used serial block-face scanning electron microscopy (SBF-SEM), a nanoscale imaging technique in x-y-z planes, to investigate 3D ultrastructural changes in the retinal neurovascular unit (NVU) associated with diabetes. We hypothesised that this approach would reveal previously uncharacterised pathological alterations that contribute to the development of diabetic retinal disease (DRD).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Retinas from male diabetic and non-diabetic mice, as well as from human male donors with and without diabetes, were prepared for SBF-SEM imaging. Retinal tissue was microdissected, fixed and embedded for serial sectioning and 3D reconstruction. Ultrastructural analysis of the NVU was performed in capillary regions exclusively within the superficial vascular plexus of both mouse and human retinas. Image stacks were processed using Microscopy Image Browser for contrast normalisation and segmentation, with 3D visualisation performed in Amira software. Quantitative analyses were conducted on pericyte\u2013endothelial cell peg-and-socket formations, cell\u2013basement membrane (BM) interactions, endothelial tubule formation and vascular BM thickness.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      SBF-SEM revealed novel 3D ultrastructural changes in the retinal NVU of diabetic mice and humans, including: (1) partial detachment and reduced frequency of pericyte\u2013endothelium peg-and-socket formations (\n                      <jats:italic>p<\/jats:italic>\n                      &lt;0.05\u20130.001); (2) localised detachment of endothelial cells and pericytes from the vascular BM (\n                      <jats:italic>p<\/jats:italic>\n                      &lt;0.05\u20130.01), along with macroglial cell retraction from the outer vascular BM; and (3) increased formation of endothelial tubules (\n                      <jats:italic>p<\/jats:italic>\n                      &lt;0.01\u20130.001). These changes were observed in the absence of any obvious vascular BM thickening, as no significant differences in mean or maximum BM thickness were found between diabetic and non-diabetic retinal capillaries analysed in this study.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions\/interpretation<\/jats:title>\n                    <jats:p>This study provides new insights into the early ultrastructural changes in the retinal NVU in DRD, offering a basis for a better understanding of the pathological processes that contribute to the development of this disease.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Data availability<\/jats:title>\n                    <jats:p>\n                      Links to all raw image stacks analysed in this article are available at\n                      <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" xlink:href=\"https:\/\/doi.org\/10.5281\/zenodo.15210333\" ext-link-type=\"uri\">https:\/\/doi.org\/10.5281\/zenodo.15210333<\/jats:ext-link>\n                      . The MATLAB vascular BM thickness measurement script is available at the GitHub link\n                      <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" xlink:href=\"https:\/\/github.com\/Curtis-WWIEM\/BM_thickness\" ext-link-type=\"uri\">https:\/\/github.com\/Curtis-WWIEM\/BM_thickness<\/jats:ext-link>\n                      .\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Graphical Abstract<\/jats:title>\n                  <\/jats:sec>","DOI":"10.1007\/s00125-025-06554-9","type":"journal-article","created":{"date-parts":[[2025,10,2]],"date-time":"2025-10-02T12:35:06Z","timestamp":1759408506000},"page":"2899-2905","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["3D electron microscopy reveals novel ultrastructural changes in the diabetic retinal neurovascular unit"],"prefix":"10.1007","volume":"68","author":[{"given":"Mona J.","family":"Albargothy","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4825-4088","authenticated-orcid":false,"given":"Evan P.","family":"Troendle","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3241-2344","authenticated-orcid":false,"given":"Ross","family":"Laws","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8166-3476","authenticated-orcid":false,"given":"Peter","family":"Barabas","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8734-3089","authenticated-orcid":false,"given":"David H. 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They also express their gratitude to the staff of the Electron Microscopy Unit at Newcastle University for their technical assistance with SBF-SEM and TEM sample preparation and imaging. The authors would like to gratefully acknowledge Professor Evelyne Sernagor, who sadly passed away this year, for her valued support and guidance as a member of MA\u2019s PhD thesis committee. Evelyne\u2019s scientific rigour and friendship will be long remembered. Some of the data presented in this study were previously shared as a platform presentation titled \u2018Investigation of the Retinal Neurovascular Unit in Diabetic Retinopathy Using 3D Electron Microscopy\u2019 at the EAsDEC meeting held in Coimbra, Portugal, 1-3 June 2023. The graphical abstract for this paper was created using BioRender. Curtis, T. (2025)\n                      \n                      .","order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Acknowledgements"}},{"value":"Links to all raw image stacks analysed in this article are available at\n                      \n                      . The MATLAB vascular BM thickness measurement script is available at the GitHub link\n                      \n                      .","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Data availability"}},{"value":"This study was supported by grants from the Randerson Foundation, Newcastle University, the Northern Ireland Health and Social Care R&D Division (STL\/4748\/13) and the Medical Research Council (MC_PC_15026). The funding bodies had no involvement in the study's design, data collection, analysis, interpretation or manuscript writing.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Funding"}},{"value":"The authors declare that there are no relationships or activities that might bias, or be perceived to bias, their work.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Authors\u2019 relationships and activities"}},{"value":"TC, MT and DS conceived the project. MA, ET, RL and PB performed the experiments and analysed the data. ET wrote the MATLAB script. TC and MA drafted the manuscript with input from MT and DS. All authors reviewed the paper for intellectual content and approved the final version for publication. MA, TC, MT and DS are the guarantors of the integrity of the work.","order":5,"name":"Ethics","group":{"name":"EthicsHeading","label":"Contribution statement"}}]}}