{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,12]],"date-time":"2026-07-12T22:02:03Z","timestamp":1783893723718,"version":"3.55.0"},"reference-count":48,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2020,11,23]],"date-time":"2020-11-23T00:00:00Z","timestamp":1606089600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["SFB1340"],"award-info":[{"award-number":["SFB1340"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["GRK2260"],"award-info":[{"award-number":["GRK2260"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Physiol."],"abstract":"<jats:p>During pregnancy, the body\u2019s hyperestrogenic state alters hepatic metabolism and synthesis. While biochemical changes related to liver function during normal pregnancy are well understood, pregnancy-associated alterations in biophysical properties of the liver remain elusive. In this study, we investigated 26 <jats:italic>ex vivo<\/jats:italic> fresh liver specimens harvested from pregnant and non-pregnant rats by diffusion-weighted imaging (DWI) and magnetic resonance elastography (MRE) in a 0.5-Tesla compact magnetic resonance imaging (MRI) scanner. Water diffusivity and viscoelastic parameters were compared with histological data and blood markers. We found livers from pregnant rats to have (i) significantly enlarged hepatocytes (26 \u00b1 15%, <jats:italic>p<\/jats:italic> &amp;lt; 0.001), (ii) increased liver stiffness (12 \u00b1 15%, <jats:italic>p<\/jats:italic> = 0.012), (iii) decreased viscosity (\u221223 \u00b1 14%, <jats:italic>p<\/jats:italic> &amp;lt; 0.001), and (iv) increased water diffusivity (12 \u00b1 11%, <jats:italic>p<\/jats:italic> &amp;lt; 0.001). In conclusion, increased stiffness and reduced viscosity of the liver during pregnancy are mainly attributable to hepatocyte enlargement. Hypertrophy of liver cells imposes fewer restrictions on intracellular water mobility, resulting in a higher hepatic water diffusion coefficient. Collectively, MRE and DWI have the potential to inform on structural liver changes associated with pregnancy in a clinical context.<\/jats:p>","DOI":"10.3389\/fphys.2020.605205","type":"journal-article","created":{"date-parts":[[2020,11,23]],"date-time":"2020-11-23T06:27:52Z","timestamp":1606112872000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":15,"title":["Changes in Liver Mechanical Properties and Water Diffusivity During Normal Pregnancy Are Driven by Cellular Hypertrophy"],"prefix":"10.3389","volume":"11","author":[{"given":"Karolina","family":"Garczy\u0144ska","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Heiko","family":"Tzsch\u00e4tzsch","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anja A.","family":"K\u00fchl","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna Sophie","family":"Morr","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ledia","family":"Lilaj","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Akvile","family":"H\u00e4ckel","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eyk","family":"Schellenberger","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nikolaus","family":"Berndt","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hermann-Georg","family":"Holzh\u00fctter","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J\u00fcrgen","family":"Braun","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ingolf","family":"Sack","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jing","family":"Guo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2020,11,23]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1326","DOI":"10.1097\/aog.0b013e3181c2bde8","article-title":"Pregnancy and laboratory studies: a reference table for clinicians.","volume":"114","author":"Abbassi-Ghanavati","year":"2009","journal-title":"Obstet Gynecol."},{"key":"B2","doi-asserted-by":"publisher","first-page":"2262","DOI":"10.1093\/jn\/114.12.2262","article-title":"Maternal organ distribution of cardiac output in the diet-restricted pregnant rat.","volume":"114","author":"Ahokas","year":"1984","journal-title":"J Nutr."},{"key":"B3","doi-asserted-by":"publisher","first-page":"4393","DOI":"10.3748\/wjg.v24.i38.4393","article-title":"Liver stiffness reversibly increases during pregnancy and independently predicts preeclampsia.","volume":"24","author":"Ammon","year":"2018","journal-title":"World J. 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