{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T00:42:56Z","timestamp":1759970576542,"version":"build-2065373602"},"reference-count":47,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,1,22]],"date-time":"2025-01-22T00:00:00Z","timestamp":1737504000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Purpose: Radiotherapy treatments are known to alter the gut microbiota. However, little is known regarding the effect of nuclear medicine treatments on gut microbiota, and it is established that nuclear medicine is inherently different from radiotherapy. To address this knowledge gap, we conducted a prospective study to identify changes in the gut microbiota of patients treated with [131I]NaI by comparing fecal samples before and after RAIT. Methods: Fecal samples of 64 patients (37 with thyroid cancer and 27 with hyperthyroidism) with indication for RAIT were collected 2 to 3 days before treatment and 8 to 10 days post-treatment. After DNA extraction, the gut microbiota\u2019s richness, diversity, and composition were analyzed by shotgun metagenomics. In addition, LEfSe was performed to compare compositional changes in specific bacteria. Results: Gut microbiome richness and diversity remained unchanged after RAIT, with few changes in its composition identified, especially in patients with hyperthyroidism. Conclusions: This study provides a conceptual and analytical basis for increasing our understanding of the effects of radiopharmaceuticals on gut microbiota. Our preliminary results indicate that RAIT, contrary to radiotherapy, does not cause major disruptions to the human gut microbiota.<\/jats:p>","DOI":"10.3390\/nu17030395","type":"journal-article","created":{"date-parts":[[2025,1,22]],"date-time":"2025-01-22T09:52:20Z","timestamp":1737539540000},"page":"395","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Gut Microbiota Is Not Significantly Altered by Radioiodine Therapy"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4537-5450","authenticated-orcid":false,"given":"Pedro","family":"Barata","sequence":"first","affiliation":[{"name":"RISE-Health, Faculdade de Ci\u00eancias da Sa\u00fade, Universidade Fernando Pessoa, Funda\u00e7\u00e3o Ensino e Cultura Fernando Pessoa, Rua Carlos da Maia 296, 4200-150 Porto, Portugal"},{"name":"Centro Hospitalar de Santo Ant\u00f3nio, Unidade Local de Sa\u00fade de Santo Ant\u00f3nio, Largo do Professor Abel Salazar, 4099-001 Porto, Portugal"}]},{"given":"Ana","family":"Oliveira","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, Centro Hospitalar e Universit\u00e1rio de S\u00e3o Jo\u00e3o, E.P.E., 4200-319 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9157-5541","authenticated-orcid":false,"given":"Raquel","family":"Soares","sequence":"additional","affiliation":[{"name":"Department of Biomedicine, Faculdade de Medicina da Universidade do Porto, 4200-319 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5489-8050","authenticated-orcid":false,"given":"Ana","family":"Fernandes","sequence":"additional","affiliation":[{"name":"RISE-Health, Faculdade de Ci\u00eancias da Sa\u00fade, Universidade Fernando Pessoa, Funda\u00e7\u00e3o Ensino e Cultura Fernando Pessoa, Rua Carlos da Maia 296, 4200-150 Porto, Portugal"},{"name":"Department of Nuclear Medicine, Centro Hospitalar e Universit\u00e1rio de S\u00e3o Jo\u00e3o, E.P.E., 4200-319 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2369","DOI":"10.1056\/NEJMra1600266","article-title":"The Human Intestinal Microbiome in Health and Disease","volume":"375","author":"Lynch","year":"2016","journal-title":"N. 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