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In our study, we used human hepatoblastoma HepG2 cells exposed to oleic (OA)\/palmitic acid (PA) (2:1 ratio, 24 h) with subsequent treatment with BR or fenofibrate (FF, a clinically used PPAR\u03b1 agonist) at clinically relevant concentrations. A significant increase in total cellular lipid content after OA\/PA treatment (p&lt;0.05) was observed. When treated with BR and FF, intracellular concentrations of OA and PA decreased significantly (p&lt;0.05). Changes in lipid content were attenuated by GW6471 (a PPAR\u03b1 antagonist) indicating the importance of PPAR\u03b1 pathway in a mechanism of action of BR and FF. Furthermore, we observed a significant increase in the gene expression of a pyruvate dehydrogenase kinase 4 after treatment with FF; FF also increased mitochondrial respiration. Collectively, our data indicate that both BR and FF reduce the accumulation of OA\/PA in HepG2 cells exposed to these fatty acids, presumably by up-regulating fatty acid oxidation via PPAR\u03b1 pathway.<\/jats:p>","DOI":"10.33549\/physiolres.935696","type":"journal-article","created":{"date-parts":[[2026,3,11]],"date-time":"2026-03-11T11:07:11Z","timestamp":1773227231000},"page":"99","source":"Crossref","is-referenced-by-count":1,"title":["Bilirubin Ameliorates Oleic and Palmitic Acid Accumulation in an In Vitro Model of MASLD"],"prefix":"10.33549","author":[{"given":"K","family":"Posp\u00ed\u0161ilov\u00e1","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"N","family":"Tulachov\u00e1","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J","family":"Onhajzer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A","family":"Dvo\u0159\u00e1k","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"L","family":"V\u00edtek","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"19169","published-online":{"date-parts":[[2026,3,10]]},"reference":[{"key":"ref0","doi-asserted-by":"crossref","unstructured":"1.\tChan WK, Chuah KH, Rajaram RB, Lim LL, Ratnasingam J, Vethakkan SR. 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