{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T22:30:23Z","timestamp":1792621823860,"version":"4.5.0"},"reference-count":51,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2023,12,22]],"date-time":"2023-12-22T00:00:00Z","timestamp":1703203200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NUTRIM Graduate Program"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The comet assay-based in vitro DNA repair assay has become a common tool for quantifying base excision repair (BER) activity in human lymphocytes or cultured cells. Here, we optimized the protocol for studying BER in human placental tissue because the placenta is a non-invasive tissue for biomonitoring of early-life exposures, and it can be used to investigate molecular mechanisms associated with prenatal disorders. The optimal protein concentration of placental protein extracts for optimal damage recognition and incision was 2 mg protein\/mL. The addition of aphidicolin did not lead to reduced non-specific incisions and was, therefore, not included in the optimized protocol. The interval between sample collection and analysis did not affect BER activity up to 70 min. Finally, this optimized protocol was tested on pre-eclamptic (PE) placental tissues (n = 11) and significantly lower BER activity in PE placentas compared to controls (n = 9) was observed. This was paralleled by a significant reduction in the expression of BER-related genes and increased DNA oxidation in PE placentas. Our study indicates that BER activity can be determined in placentas, and lower activity is present in PE compared with healthy. These findings should be followed up in prospective clinical investigations to examine BER\u2019s role in the advancement of PE.<\/jats:p>","DOI":"10.3390\/ijms25010187","type":"journal-article","created":{"date-parts":[[2023,12,22]],"date-time":"2023-12-22T04:44:40Z","timestamp":1703220280000},"page":"187","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Optimizing the Comet Assay-Based In Vitro DNA Repair Assay for Placental Tissue: A Pilot Study with Pre-Eclamptic Patients"],"prefix":"10.3390","volume":"25","author":[{"given":"Anastasiya","family":"Mircheva","sequence":"first","affiliation":[{"name":"Department of Pharmacology and Toxicology, School for Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0871-7789","authenticated-orcid":false,"given":"Philippe","family":"Vangrieken","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, School of Cardiovascular diseases (CARIM), Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Salwan","family":"Al-Nasiry","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Maastricht University Medical Center+, P. Debyelaan 25, 6229 HX Maastricht, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frederik-Jan","family":"van Schooten","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, School for Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roger W. L.","family":"Godschalk","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, School for Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sabine A. S.","family":"Langie","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, School for Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,12,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1097\/WOX.0b013e3182439613","article-title":"Oxidative stress and antioxidant defense","volume":"5","author":"Birben","year":"2012","journal-title":"World Allergy Organ. J."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"479","DOI":"10.3109\/10715761003667554","article-title":"Reactive oxygen species in cancer","volume":"44","author":"Liou","year":"2010","journal-title":"Free Radic. Res."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"249","DOI":"10.1385\/MB:26:3:249","article-title":"The comet assay for DNA damage and repair: Principles, applications, and limitations","volume":"26","author":"Collins","year":"2004","journal-title":"Mol. 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