{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T00:14:37Z","timestamp":1782260077932,"version":"3.54.5"},"reference-count":46,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2020,10,1]],"date-time":"2020-10-01T00:00:00Z","timestamp":1601510400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NATIONAL UNIVERSITY OF LA PLATA (UNLP)","award":["PPID\/X024"],"award-info":[{"award-number":["PPID\/X024"]}]},{"name":"NATIONAL UNIVERSITY OF LA PLATA (UNLP)","award":["PID\/X762"],"award-info":[{"award-number":["PID\/X762"]}]},{"name":"NATIONAL UNIVERSITY OF LA PLATA (UNLP)","award":["PPID\/X048"],"award-info":[{"award-number":["PPID\/X048"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxins"],"abstract":"<jats:p>Two microcystins, MC-LR and [D-Leu1]MC-LR, present in La Plata Basin blooms, are differentiated by substitution of D-Alanine for D-Leucine at position 1. Our objective was to evaluate acute toxicity of [D-Leu1]MC-LR and MC-LR in mice (N:NIH Swiss) and beans (Phaseolus vulgaris). We observed variations in [D-Leu1]MC-LR lethal doses with respect to those reported for MC-LR (100 \u03bcg\/kg), with an increased liver\/body weight ratio and intrahepatic hemorrhages in mice exposed to 50\u2013200 \u03bcg [D-Leu1]MC-LR\/kg and slight steatosis after a single 25 \u03bcg [D-Leu1]MC-LR\/kg i.p. dose. Our study in the plant model showed alterations in germination, development, morphology and TBARs levels after a single contact with the toxins during imbibition (3.5 and 15 \u00b5g\/mL), those treated with [D-Leu1]MC-LR being more affected than those treated with the same concentration of MC-LR. Protein phosphatase 1 (PP1) IC50 values were 40.6 nM and 5.3 nM for [D-Leu1]MC-LR and MC-LR, respectively. However, the total phosphatase activity test in root homogenate showed 60% inhibition for [D-Leu1]MC-LR and 12% for MC-LR. In mouse liver homogenate, 50% inhibition was observed for [D-Leu1]MC-LR and 40% for MC-LR. Our findings indicate the need for further research into [D-Leu1]MC-LR toxicity since together with oxidative stress, the possible inhibition of other phosphatases could explain the differences detected in the potency of the two toxins.<\/jats:p>","DOI":"10.3390\/toxins12100632","type":"journal-article","created":{"date-parts":[[2020,10,1]],"date-time":"2020-10-01T09:04:12Z","timestamp":1601543052000},"page":"632","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["[D-Leu1]MC-LR Has Lower PP1 Inhibitory Capability and Greater Toxic Potency than MC-LR in Animal and Plant Tissues"],"prefix":"10.3390","volume":"12","author":[{"given":"Daniela","family":"Sedan","sequence":"first","affiliation":[{"name":"Center for Environmental Research (CIM), National Council for Scientific and Technical Research (CONICET), National University of La Plata (UNLP), La Plata 1900, Argentina"},{"name":"Area of Toxicology, School of Exact Sciences, National University of La Plata (UNLP), La Plata 1900, Argentina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luciano","family":"Malaissi","sequence":"additional","affiliation":[{"name":"Center for Environmental Research (CIM), National Council for Scientific and Technical Research (CONICET), National University of La Plata (UNLP), La Plata 1900, Argentina"},{"name":"Area of Toxicology, School of Exact Sciences, National University of La Plata (UNLP), La Plata 1900, Argentina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristian Adri\u00e1n","family":"Vaccarini","sequence":"additional","affiliation":[{"name":"Center for Environmental Research (CIM), National Council for Scientific and Technical Research (CONICET), National University of La Plata (UNLP), La Plata 1900, Argentina"},{"name":"Area of Toxicology, School of Exact Sciences, National University of La Plata (UNLP), La Plata 1900, Argentina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ezequiel","family":"Ventosi","sequence":"additional","affiliation":[{"name":"Area of Toxicology, School of Exact Sciences, National University of La Plata (UNLP), La Plata 1900, Argentina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mart\u00edn","family":"Laguens","sequence":"additional","affiliation":[{"name":"Pathology B Cathedra, School of Medical Sciences, National University of La Plata (UNLP), La Plata 1900, Argentina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lorena","family":"Rosso","sequence":"additional","affiliation":[{"name":"Area of Toxicology, School of Exact Sciences, National University of La Plata (UNLP), La Plata 1900, Argentina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Leda","family":"Giannuzzi","sequence":"additional","affiliation":[{"name":"Research Center in Food Cryotechnology (CIDCA), National Council for Scientific and Technical Research (CONICET), La Plata 1900, Argentina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6593-5294","authenticated-orcid":false,"given":"Dar\u00edo","family":"Andrinolo","sequence":"additional","affiliation":[{"name":"Center for Environmental Research (CIM), National Council for Scientific and Technical Research (CONICET), National University of La Plata (UNLP), La Plata 1900, Argentina"},{"name":"Area of Toxicology, School of Exact Sciences, National University of La Plata (UNLP), La Plata 1900, Argentina"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"57","DOI":"10.1126\/science.1155398","article-title":"Blooms like it hot","volume":"320","author":"Pearl","year":"2008","journal-title":"Science"},{"key":"ref_2","unstructured":"Ownby, C.A., and Odell, G.V. 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