{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T06:14:49Z","timestamp":1791526489343,"version":"4.3.4"},"reference-count":37,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,4,14]],"date-time":"2023-04-14T00:00:00Z","timestamp":1681430400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004040","name":"KU Leuven Internal Funds","doi-asserted-by":"publisher","award":["C24\/17\/076"],"award-info":[{"award-number":["C24\/17\/076"]}],"id":[{"id":"10.13039\/501100004040","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004040","name":"KU Leuven Internal Funds","doi-asserted-by":"publisher","award":["1830517N"],"award-info":[{"award-number":["1830517N"]}],"id":[{"id":"10.13039\/501100004040","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003130","name":"Flanders Research Foundation (FWO Vlaanderen)","doi-asserted-by":"publisher","award":["C24\/17\/076"],"award-info":[{"award-number":["C24\/17\/076"]}],"id":[{"id":"10.13039\/501100003130","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003130","name":"Flanders Research Foundation (FWO Vlaanderen)","doi-asserted-by":"publisher","award":["1830517N"],"award-info":[{"award-number":["1830517N"]}],"id":[{"id":"10.13039\/501100003130","id-type":"DOI","asserted-by":"publisher"}]},{"name":"UCB Biopharma SPRL","award":["C24\/17\/076"],"award-info":[{"award-number":["C24\/17\/076"]}]},{"name":"UCB Biopharma SPRL","award":["1830517N"],"award-info":[{"award-number":["1830517N"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceutics"],"abstract":"<jats:p>Parkinson\u2019s disease, one of the most common neurodegenerative diseases, may not only affect the motor system, but also the physiology of the gastrointestinal tract. Delayed gastric emptying, impaired motility and altered intestinal bacteria are well-established consequences of the disease, which can have a pronounced effect on the absorption of orally administered drugs. In contrast, no studies have been performed into the composition of intestinal fluids. It is not unlikely that Parkinson\u2019s disease also affects the composition of intestinal fluids, a critical factor in the in vitro and in silico simulation of drug dissolution, solubilization and absorption. In the current study, duodenal fluids were aspirated from Parkinson\u2019s disease (PD) patients and age-matched healthy controls (healthy controls, HC) consecutively in fasted and fed conditions. The fluids were then characterized for pH, buffer capacity, osmolality, total protein, phospholipids, bile salts, cholesterol and lipids. In a fasted state, the intestinal fluid composition was highly similar in PD patients and healthy controls. In general, the same was true for fed-state fluids, apart from a slightly slower and less pronounced initial change in factors directly affected by the meal (i.e., buffer capacity, osmolality, total protein and lipids) in PD patients. The absence of a fast initial increase for these factors immediately after meal intake, as was observed in healthy controls, might result from slower gastric emptying in PD patients. Irrespective of the prandial state, a higher relative amount of secondary bile salts was observed in PD patients, potentially indicating altered intestinal bacterial metabolism. Overall, the data from this study indicate that only minor disease-specific adjustments in small intestinal fluid composition should be considered when simulating intestinal drug absorption in PD patients.<\/jats:p>","DOI":"10.3390\/pharmaceutics15041243","type":"journal-article","created":{"date-parts":[[2023,4,14]],"date-time":"2023-04-14T04:54:24Z","timestamp":1681448064000},"page":"1243","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Characterization of Aspirated Duodenal Fluids from Parkinson\u2019s Disease Patients"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6863-7903","authenticated-orcid":false,"given":"Tom","family":"de Waal","sequence":"first","affiliation":[{"name":"Drug Delivery and Disposition, KU Leuven, 3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1478-6174","authenticated-orcid":false,"given":"Joachim","family":"Brouwers","sequence":"additional","affiliation":[{"name":"Drug Delivery and Disposition, KU Leuven, 3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philippe","family":"Berben","sequence":"additional","affiliation":[{"name":"Pharmaceutical Sciences, UCB Pharma SA, 1420 Braine-l\u2019Alleud, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Talia","family":"Flanagan","sequence":"additional","affiliation":[{"name":"Pharmaceutical Sciences, UCB Pharma SA, 1420 Braine-l\u2019Alleud, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jan","family":"Tack","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Hepatology, University Hospitals Leuven, 3000 Leuven, Belgium"},{"name":"Translational Research Center for Gastrointestinal Disorders, TARGID, KU Leuven, 3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wim","family":"Vandenberghe","sequence":"additional","affiliation":[{"name":"Department of Neurology, University Hospitals Leuven, 3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tim","family":"Vanuytsel","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology and Hepatology, University Hospitals Leuven, 3000 Leuven, Belgium"},{"name":"Translational Research Center for Gastrointestinal Disorders, TARGID, KU Leuven, 3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2595-388X","authenticated-orcid":false,"given":"Patrick","family":"Augustijns","sequence":"additional","affiliation":[{"name":"Drug Delivery and Disposition, KU Leuven, 3000 Leuven, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,14]]},"reference":[{"key":"ref_1","first-page":"6762528","article-title":"Gastrointestinal dysfunctions in Parkinson\u2019s disease: Symptoms and treatments","volume":"2016","author":"Poirier","year":"2016","journal-title":"Park. 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