{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T01:52:18Z","timestamp":1792029138805,"version":"4.4.0"},"reference-count":51,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,11,3]],"date-time":"2021-11-03T00:00:00Z","timestamp":1635897600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antioxidants"],"abstract":"<jats:p>The aim of the present paper is to assess the relationship between oxysterol levels and retinal microvascular function in individuals of various age groups, free of clinically evident diseases. Forty-two apparently healthy individuals were included in the present study (group 1: 19\u201330 years, group 2: 31\u201350 years, and group 3: 51\u201370 years). Retinal microvascular function was assessed using the dynamic retinal vessel analyzer (DVA, IMEDOS GmbH, Jena, Germany). Fasting plasma was obtained from all subjects and quantification of monohydroxy and dihydroxy oxysterols assessment was performed using LC-MS\/MS following reverse phase chromatography. A Griess assay was used to evaluate the Nitric Oxide (NO) concentration in all individuals. The glutathione redox ratio was also analyzed by means of whole blood glutathione recycling assay. In all participants, the levels of 7-Ketocholesterol, 25-hydroxycholesterol and 7\u03b2-hydroxycholesterol correlated significantly and positively with the time to maximum arteriolar dilation. In addition, 25-hydroxycholesterol and 7\u03b2-hydroxycholesterol negatively correlated to the percentage of maximum arteriolar dilation. A negative correlation was observed for 27-hydroxycholesterol and 7\u03b2-hydroxycholesterol with microvascular arteriolar constriction. These results suggest that, with age, abnormal oxysterol levels correlate with early changes in microvascular bed function. This relationship could signal early risk for cardiovascular diseases (CVDs) in an ageing population.<\/jats:p>","DOI":"10.3390\/antiox10111756","type":"journal-article","created":{"date-parts":[[2021,11,3]],"date-time":"2021-11-03T17:59:38Z","timestamp":1635962378000},"page":"1756","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Oxysterols and Retinal Microvascular Dysfunction as Early Risk Markers for Cardiovascular Disease in Normal, Ageing Individuals"],"prefix":"10.3390","volume":"10","author":[{"given":"Hala","family":"Shokr","sequence":"first","affiliation":[{"name":"Vascular Research Laboratory, College of Health and Life Sciences, Aston University, Birmingham B4 7ET, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Irundika HK","family":"Dias","sequence":"additional","affiliation":[{"name":"Aston Medical Research Institute, Aston Medical School, Aston University, Birmingham B4 7ET, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Doina","family":"Gherghel","sequence":"additional","affiliation":[{"name":"Vascular Research Laboratory, College of Health and Life Sciences, Aston University, Birmingham B4 7ET, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"960","DOI":"10.1038\/nature04482","article-title":"Retinal angiogenesis in development and disease","volume":"438","author":"Gariano","year":"2005","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1016\/j.ejvs.2004.12.019","article-title":"A Review of Methods Currently Used for Assessment of In vivo Endothelial Function","volume":"29","author":"Alam","year":"2005","journal-title":"Eur. 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