{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T01:58:18Z","timestamp":1785463098795,"version":"3.56.0"},"reference-count":49,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2020,9,4]],"date-time":"2020-09-04T00:00:00Z","timestamp":1599177600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008015","name":"Agria Djurf\u00f6rs\u00e4kring","doi-asserted-by":"publisher","award":["N2017-0003, N2016-0003"],"award-info":[{"award-number":["N2017-0003, N2016-0003"]}],"id":[{"id":"10.13039\/501100008015","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Sveland Foundation","award":["No grant number allocated"],"award-info":[{"award-number":["No grant number allocated"]}]},{"name":"LifePharm Centre for In Vivo Pharmacology, Copenhagen, Denmark","award":["No grant number allocated"],"award-info":[{"award-number":["No grant number allocated"]}]},{"name":"University of Copenhagen Foundation for Scientific Studies in Companion Animals","award":["No grant number allocated"],"award-info":[{"award-number":["No grant number allocated"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antioxidants"],"abstract":"<jats:p>Coenzyme Q10 (Q10) is a mitochondrial cofactor and an antioxidant with the potential to combat oxidative stress in heart failure. This study aims to determine the pharmacokinetics of repeated oral dosing of Q10 in Cavalier King Charles Spaniels (CKCS) with spontaneous myxomatous mitral valve disease (MMVD) and to evaluate echocardiographic parameters, circulating cardiac biomarkers, and quality of life (QoL) after treatment. The study is a randomized, placebo-controlled, single-blinded crossover study. Nineteen CKCS with MMVD were randomized to receive 100 mg Q10 (ubiquinone) bi-daily for three weeks, then placebo (or in reverse order). Clinical examination, blood sampling, echocardiography, and QoL assessment were performed before and after each treatment phase. Q10 plasma concentrations were determined in plasma using a validated high-performance liquid chromatography method using electrochemical detection (HPLC-ECD). Eighteen CKCS were included in the analyses. Total plasma concentration of Q10 increased significantly (p &lt; 0.0001) from baseline (median, 0.92 \u00b5g\/mL; interquartile range (IQR), 0.70\u20131.26) to after treatment (median, 3.51 \u00b5g\/mL; IQR, 2.30\u20136.88). Thirteen dogs reached the threshold of a total plasma Q10 concentration of \u22652.0 \u00b5g\/mL. The average half-life (T1\/2) of Q10 was 2.95 days (IQR, 1.75\u20134.02). No significant differences were observed in clinical MMVD severity, and the owner perceived QoL between Q10 and placebo treatment. The solubilized Q10 formulation was well-tolerated in the dogs. Individual variation in plasma concentrations was observed following oral treatment. A long-term placebo-controlled trial is warranted in dogs with MMVD to determine long-term efficacy on the clinical severity of MMVD.<\/jats:p>","DOI":"10.3390\/antiox9090827","type":"journal-article","created":{"date-parts":[[2020,9,4]],"date-time":"2020-09-04T11:24:24Z","timestamp":1599218664000},"page":"827","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Pharmacokinetics of Repeated Oral Dosing with Coenzyme Q10 in Cavalier King Charles Spaniels with Myxomatous Mitral Valve Disease"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4834-8482","authenticated-orcid":false,"given":"Liselotte B.","family":"Christiansen","sequence":"first","affiliation":[{"name":"Section for Experimental Animal Models, Department of Veterinary and Animal Sciences, University of Copenhagen, Ridebanevej 9, 1870 Frederiksberg C, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Malene K.","family":"Morsing","sequence":"additional","affiliation":[{"name":"Section for Experimental Animal Models, Department of Veterinary and Animal Sciences, University of Copenhagen, Ridebanevej 9, 1870 Frederiksberg C, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7824-3323","authenticated-orcid":false,"given":"Maria Josefine","family":"Reimann","sequence":"additional","affiliation":[{"name":"Section for Experimental Animal Models, Department of Veterinary and Animal Sciences, University of Copenhagen, Ridebanevej 9, 1870 Frederiksberg C, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Torben","family":"Martinussen","sequence":"additional","affiliation":[{"name":"Section for Biostatistics, Department of Public Health, Faculty of Health and Medical Sciences, University of Copenhagen, \u00d8ster Farimagsgade 5B, 1014 Copenhagen K, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zita","family":"Birlie","sequence":"additional","affiliation":[{"name":"Section for Experimental Animal Models, Department of Veterinary and Animal Sciences, University of Copenhagen, Ridebanevej 9, 1870 Frederiksberg C, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6375-8394","authenticated-orcid":false,"given":"Anne Marie V.","family":"Schou-Pedersen","sequence":"additional","affiliation":[{"name":"Section for Experimental Animal Models, Department of Veterinary and Animal Sciences, University of Copenhagen, Ridebanevej 9, 1870 Frederiksberg C, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6514-8407","authenticated-orcid":false,"given":"Jens","family":"Lykkesfeldt","sequence":"additional","affiliation":[{"name":"Section for Experimental Animal Models, Department of Veterinary and Animal Sciences, University of Copenhagen, Ridebanevej 9, 1870 Frederiksberg C, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lisbeth H.","family":"Olsen","sequence":"additional","affiliation":[{"name":"Section for Experimental Animal Models, Department of Veterinary and Animal Sciences, University of Copenhagen, Ridebanevej 9, 1870 Frederiksberg C, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,9,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"894","DOI":"10.1111\/j.1939-1676.2006.tb01803.x","article-title":"Heart disease as a cause of death in insured Swedish dogs younger than 10 years of age","volume":"20","author":"Egenvall","year":"2006","journal-title":"J. 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