{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T05:02:37Z","timestamp":1790830957144,"version":"4.1.0"},"reference-count":32,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T00:00:00Z","timestamp":1790812800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell. Infect. Microbiol."],"abstract":"<jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>\n                      To investigate the antibacterial effects of LED phototherapy on\n                      <jats:italic>Gardnerella vaginalis<\/jats:italic>\n                      (\n                      <jats:italic>Gv<\/jats:italic>\n                      ) and\n                      <jats:italic>Escherichia coli<\/jats:italic>\n                      (\n                      <jats:italic>E. coli<\/jats:italic>\n                      ), optimize key irradiation conditions for LED phototherapy by establishing an\n                      <jats:italic>in vivo<\/jats:italic>\n                      infection model, and evaluate its feasibility for treating bacterial vaginosis.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Bacterial colonies were irradiated with LEDs at different wavelengths (405 nm, 415 nm, 430 nm, 630 nm, 850 nm). Bacterial survival and morphology were assessed via colony counting, SYTO9\/PI fluorescence staining, and scanning electron microscopy. Intracellular oxidative stress and antioxidant systems were quantitatively measured. Genomic DNA integrity was analyzed by agarose gel electrophoresis to validate the bactericidal mechanism. The effects on vaginal epithelial cell (VK2\/E6E7). viability were assessed using CCK-8 assays, ROS detection, and SYTO9\/PI live\/dead staining. A rat model of bacterial vaginosis was established to optimize vaginal LED irradiation parameters, with inflammatory cell infiltration assessed by H&amp;amp;E staining, and expression levels of IL-1\u03b2 and TNF-\u03b1 in vaginal tissues evaluated by immunohistochemistry (IHC) with semi-quantitative image analysis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Among the tested wavelengths, 415 nm LED demonstrated optimal antibacterial efficacy. At 50 mW\/cm\u00b2 intensity for 30\u00a0min, it exhibited the most significant bactericidal effect against\n                      <jats:italic>Gv<\/jats:italic>\n                      and\n                      <jats:italic>E. coli<\/jats:italic>\n                      . This condition induced substantial ROS production in bacteria, inhibited SOD and CAT activity, leading to bacterial cell membrane damage and genomic DNA fragmentation. This irradiation condition exhibited no significant toxicity to vaginal epithelial cells VK2\/E6E7. In a rat model, LED treatment under these conditions significantly improved vaginal inflammation symptoms and pathological histological findings, while reducing IL- 1\u03b2 and TNF-\u03b1 expression.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>\n                      This study established the optimal LED irradiation conditions for BV-associated pathogens as 415 nm wavelength, 50 mW\/cm\u00b2 power, and 30\u00a0min exposure (irradiation dose 90 J\/cm\u00b2). These conditions exert significant antibacterial effects against\n                      <jats:italic>Gv<\/jats:italic>\n                      and\n                      <jats:italic>E. coli<\/jats:italic>\n                      by inducing bacterial ROS production, while maintaining excellent cellular safety. In rat cell models, it simultaneously demonstrated anti-inflammatory and tissue repair potential in both bacterial and\n                      <jats:italic>in vivo<\/jats:italic>\n                      settings, offering a novel therapeutic strategy for the clinical management of bacterial vaginosis.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fcimb.2026.1836549","type":"journal-article","created":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T04:35:28Z","timestamp":1790829328000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Parameter optimization and mechanism of action of Light\u2011Emitting Diode phototherapy in a rat model of bacterial vaginosis"],"prefix":"10.3389","volume":"16","author":[{"given":"Xiuxin","family":"Chen","sequence":"first","affiliation":[{"name":"Ningxia Medical University","place":["Yinchuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xinyi","family":"Qi","sequence":"additional","affiliation":[{"name":"Ningxia Medical University","place":["Yinchuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuan","family":"Ma","sequence":"additional","affiliation":[{"name":"Department of Gynecology, General Hospital of Ningxia Medical University","place":["Yinchuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bowei","family":"Li","sequence":"additional","affiliation":[{"name":"Ningxia Medical University","place":["Yinchuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu\u2011e","family":"Yang","sequence":"additional","affiliation":[{"name":"Ningxia Medical University","place":["Yinchuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhuo","family":"Xiong","sequence":"additional","affiliation":[{"name":"Ningxia Medical University","place":["Yinchuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanhui","family":"Yang","sequence":"additional","affiliation":[{"name":"Ningxia Key Laboratory of Infection and Immunity, School of Basic Medical Sciences, Ningxia Medical University","place":["Yinchuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chunfang","family":"Ha","sequence":"additional","affiliation":[{"name":"Department of Gynecology, General Hospital of Ningxia Medical University","place":["Yinchuan, China"]},{"name":"Key Laboratory of Fertility Preservation and Maintenance of Ministry of Education, Ningxia Medical University","place":["Yinchuan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,10,1]]},"reference":[{"key":"B19","doi-asserted-by":"publisher","first-page":"171","DOI":"10.3390\/antibiotics9040171","article-title":"Visible light as an antimicrobial strategy for inactivation of Pseudomonas fluorescens and Staphylococcus epidermidis biofilms","volume":"9","author":"Angarano","year":"2020","journal-title":"Antibiotics"},{"key":"B27","doi-asserted-by":"publisher","first-page":"e02833","DOI":"10.1128\/spectrum.02833-22","article-title":"New insights into the bacterial targets of antimicrobial blue light","volume":"11","author":"dos Anjos","year":"2023","journal-title":"Microbiol. 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