{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T22:48:15Z","timestamp":1768258095959,"version":"3.49.0"},"reference-count":43,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,23]],"date-time":"2023-01-23T00:00:00Z","timestamp":1674432000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia (FCT), Portugal","doi-asserted-by":"publisher","award":["UID\/DTP\/04138\/2019"],"award-info":[{"award-number":["UID\/DTP\/04138\/2019"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia (FCT), Portugal","doi-asserted-by":"publisher","award":["UIDB\/04138\/2020"],"award-info":[{"award-number":["UIDB\/04138\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia (FCT), Portugal","doi-asserted-by":"publisher","award":["UIDB\/00276\/2020"],"award-info":[{"award-number":["UIDB\/00276\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia (FCT), Portugal","doi-asserted-by":"publisher","award":["LA\/P\/0059\/2020"],"award-info":[{"award-number":["LA\/P\/0059\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"national funds through FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["UID\/DTP\/04138\/2019"],"award-info":[{"award-number":["UID\/DTP\/04138\/2019"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"national funds through FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/04138\/2020"],"award-info":[{"award-number":["UIDB\/04138\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"national funds through FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/00276\/2020"],"award-info":[{"award-number":["UIDB\/00276\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"national funds through FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["LA\/P\/0059\/2020"],"award-info":[{"award-number":["LA\/P\/0059\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceuticals"],"abstract":"<jats:p>The present work investigates the effects of chitosan-hyaluronic acid-epoetin beta (CS\/HA-EPO\u03b2) nanoparticles after topical ocular administration in a rat glaucoma model. Wistar Hannover rats (n = 24) were submitted to a complete ophthalmological examination and electroretinography, followed by glaucoma induction in their right eye on day 1 of the study. Treatment group (T) received CS\/HA-EPO\u03b2 nanocarriers (n = 12), while the control group (C) received only empty ones. Electroretinography was repeated on day 3 (n = 24) and before euthanasia on day 7 (n = 8), 14 (n = 8), and 21 (n = 8), followed by bilateral enucleation and histological assessment. The animals showed good tolerance to the nanoformulation. Maximum IOP values on the right eye occurred shortly after glaucoma induction (T = 62.6 \u00b1 8.3 mmHg; C = 63.6 \u00b1 7.9 mmHg). Animals from the treated group presented a tendency for faster recovery of retinal electrical activity (p &gt; 0.05). EPO\u03b2 was detected on the retina of all treated eyes using immunofluorescence. Control animals presented with thinner retinas compared to the treated ones (p &lt; 0.05). Therefore, topical ocular administration of CS\/HA-EPO\u03b2 nanoparticles enabled EPO\u03b2 delivery to the retina of glaucomatous rats and promoted an earlier retinal recovery, confirming EPO\u03b2\u2019s neuroprotective effects. The encouraging results of this preclinical study pave the way for new strategies for topical ocular administration of neuroprotective compounds.<\/jats:p>","DOI":"10.3390\/ph16020164","type":"journal-article","created":{"date-parts":[[2023,1,23]],"date-time":"2023-01-23T02:27:45Z","timestamp":1674440865000},"page":"164","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Topical Administration of a Nanoformulation of Chitosan-Hyaluronic Acid-Epoetin Beta in a Rat Model of Glaucoma"],"prefix":"10.3390","volume":"16","author":[{"given":"Beatriz","family":"Silva","sequence":"first","affiliation":[{"name":"CIISA\u2014Centre for Interdisciplinary Research in Animal Health, Faculty of Veterinary Medicine, Universidade de Lisboa Avenida da Universidade T\u00e9cnica, 1300-477 Lisbon, Portugal"},{"name":"Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 1300-477 Lisbon, Portugal"},{"name":"Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6799-2740","authenticated-orcid":false,"given":"L\u00eddia M.","family":"Gon\u00e7alves","sequence":"additional","affiliation":[{"name":"Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2688-0459","authenticated-orcid":false,"given":"Berta S\u00e3o","family":"Braz","sequence":"additional","affiliation":[{"name":"CIISA\u2014Centre for Interdisciplinary Research in Animal Health, Faculty of Veterinary Medicine, Universidade de Lisboa Avenida da Universidade T\u00e9cnica, 1300-477 Lisbon, Portugal"},{"name":"Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 1300-477 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9383-1310","authenticated-orcid":false,"given":"Esmeralda","family":"Delgado","sequence":"additional","affiliation":[{"name":"CIISA\u2014Centre for Interdisciplinary Research in Animal Health, Faculty of Veterinary Medicine, Universidade de Lisboa Avenida da Universidade T\u00e9cnica, 1300-477 Lisbon, Portugal"},{"name":"Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 1300-477 Lisbon, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.preteyeres.2011.08.001","article-title":"Understanding glaucomatous damage: Anatomical and functional data from ocular hypertensive rodent retinas","volume":"31","year":"2012","journal-title":"Prog. 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