{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T21:27:32Z","timestamp":1775856452966,"version":"3.50.1"},"reference-count":35,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2020,8,5]],"date-time":"2020-08-05T00:00:00Z","timestamp":1596585600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006109","name":"Vedeck\u00e1 Grantov\u00e1 Agent\u00fara M\u0160VVa\u0160 SR a SAV","doi-asserted-by":"publisher","award":["2\/0019\/19"],"award-info":[{"award-number":["2\/0019\/19"]}],"id":[{"id":"10.13039\/501100006109","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100006109","name":"Vedeck\u00e1 Grantov\u00e1 Agent\u00fara M\u0160VVa\u0160 SR a SAV","doi-asserted-by":"publisher","award":["2\/0154\/20"],"award-info":[{"award-number":["2\/0154\/20"]}],"id":[{"id":"10.13039\/501100006109","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Indole derivatives such as isatin (a natural compound), cemtirestat, stobadine, and its derivatives (synthetic compounds) are known to have numerous positive effects on human health due to regulation of oxidative status. The aim of the study was to assess radical scavenging capacities of these compounds and explore their potential protective effects against reactive oxygen species formed during Cu(II) ions and ascorbate-induced degradation of high-molar-mass hyaluronan. Based on the IC50 values determined by the ABTS assay, the most effective compound was SM1M3EC2\u00b7HCl reaching the value \u2248 11 \u00b5mol\/L. The lowest IC50 value reached in the DPPH assay was reported for cemtirestat \u2248 3 \u00b5mol\/L. Great potency of inhibition of hyaluronan degradation was shown by cemtirestat, followed by isatin even at low concentration 10 \u00b5mol\/L. On the other hand, stobadine\u00b72HCl had also a protective effect on hyaluronan degradation, however at greater concentrations compared to cemtirestat or isatin. SME1i-ProC2\u00b7HCl reported to be a less effective compound and SM1M3EC2\u00b7HCl can be considered almost ineffective compared to stobadine\u00b72HCl. In conclusion, our results showed that both isatin and cemtirestat were capable of attenuating the degradation of high-molar-mass hyaluronan due to their ability to complex\/sequester cupric ions.<\/jats:p>","DOI":"10.3390\/ijms21165609","type":"journal-article","created":{"date-parts":[[2020,8,5]],"date-time":"2020-08-05T15:13:18Z","timestamp":1596640398000},"page":"5609","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Oxidative Degradation of High-Molar-Mass Hyaluronan: Effects of Some Indole Derivatives to Hyaluronan Decay"],"prefix":"10.3390","volume":"21","author":[{"given":"Katar\u00edna","family":"Valachov\u00e1","sequence":"first","affiliation":[{"name":"Centre of Experimental Medicine of the Slovak Academy of Sciences, Institute of Experimental Pharmacology &amp; Toxicology, D\u00fabravsk\u00e1 cesta 9, SK-84104 Bratislava, Slovakia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6958-1024","authenticated-orcid":false,"given":"Mojm\u00edr","family":"Mach","sequence":"additional","affiliation":[{"name":"Centre of Experimental Medicine of the Slovak Academy of Sciences, Institute of Experimental Pharmacology &amp; Toxicology, D\u00fabravsk\u00e1 cesta 9, SK-84104 Bratislava, Slovakia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ladislav","family":"\u0160olt\u00e9s","sequence":"additional","affiliation":[{"name":"Centre of Experimental Medicine of the Slovak Academy of Sciences, Institute of Experimental Pharmacology &amp; Toxicology, D\u00fabravsk\u00e1 cesta 9, SK-84104 Bratislava, Slovakia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,8,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"535","DOI":"10.1006\/abbi.1993.1074","article-title":"The pecking order of free radicals and antioxidants: Lipid peroxidation, alpha-tocopherol, and ascorbate","volume":"300","author":"Buettner","year":"1993","journal-title":"Arch. 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