{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,17]],"date-time":"2026-10-17T23:19:32Z","timestamp":1792279172590,"version":"4.4.0"},"reference-count":51,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2023,7,6]],"date-time":"2023-07-06T00:00:00Z","timestamp":1688601600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000066","name":"National Institute of Environmental Health Sciences","doi-asserted-by":"publisher","award":["R01ES032558"],"award-info":[{"award-number":["R01ES032558"]}],"id":[{"id":"10.13039\/100000066","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Microcystin-leucine arginine (MCLR) is one of the most common and toxic microcystin variants, a class of cyanotoxins produced by cyanobacteria. A major molecular mechanism for MCLR-elicited liver toxicity involves the dysregulation of protein phosphorylation through protein phosphatase (PP) inhibition and mitogen-activated protein kinase (MAPK) modulation. In this study, specific pharmacological MAPK inhibitors were used in HepaRG cells to examine the pathways associated with MCLR cytotoxicity. SB203580 (SB), a p38 inhibitor, rescued HepaRG cell viability, whereas treatment with SP600125 (JNK inhibitor), MK2206 (AKT inhibitor), or N-acetylcysteine (reactive oxygen species scavenger) did not. Phosphoproteomic analysis revealed that phosphosites\u2014which were altered by the addition of SB compared to MCLR treatment alone\u2014included proteins involved in RNA processing, cytoskeletal stability, DNA damage response, protein degradation, and cell death. A closer analysis of specific proteins in some of these pathways indicated that SB reversed the MCLR-mediated phosphorylation of the necroptosis-associated proteins, the mixed lineage kinase domain-like protein (MLKL), receptor-interacting serine\/threonine kinase 1 (RIP1), DNA damage response proteins, ataxia telangiectasia and Rad3-related kinase (ATR), and checkpoint kinase 1 (CHK1). Overall, these data implicate p38\/MK2, DNA damage, and necroptosis in MCLR-mediated hepatotoxicity, and suggest these pathways may be targets for prevention prior to, or treatment after, MCLR toxicity.<\/jats:p>","DOI":"10.3390\/ijms241311168","type":"journal-article","created":{"date-parts":[[2023,7,7]],"date-time":"2023-07-07T01:41:36Z","timestamp":1688694096000},"page":"11168","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Involvement of the p38\/MK2 Pathway in MCLR Hepatotoxicity Revealed through MAPK Pharmacological Inhibition and Phosphoproteomics in HepaRG Cells"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0509-7852","authenticated-orcid":false,"given":"Katherine D.","family":"Lynch","sequence":"first","affiliation":[{"name":"Department of Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dayne T.","family":"Iverson","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Namrata K.","family":"Bachhav","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael Ridge","family":"Call","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guihua Eileen","family":"Yue","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bhagwat","family":"Prasad","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3835-7761","authenticated-orcid":false,"given":"John D.","family":"Clarke","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1016\/j.hal.2016.11.006","article-title":"A review of microcystin detections in Estuarine and Marine waters: Environmental implications and human health risk","volume":"61","author":"Preece","year":"2017","journal-title":"Harmful Algae"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"268","DOI":"10.3390\/ijms11010268","article-title":"Molecular mechanisms of microcystin toxicity in animal cells","volume":"11","author":"Campos","year":"2010","journal-title":"Int. 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