{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:49:05Z","timestamp":1760147345999,"version":"build-2065373602"},"reference-count":54,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,30]],"date-time":"2023-01-30T00:00:00Z","timestamp":1675036800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Children"],"abstract":"<jats:p>This pilot repeated measures study aims to evaluate the dynamics of the autonomic nervous system (ANS), the hypothalamic\u2013pituitary\u2013adrenal (HPA) axis, and\/or their interplay with low-level inflammation in healthy schoolchildren during consecutive extrinsic stimuli. Twenty healthy schoolchildren and adolescents aged 11\u201314 years (12.5 \u00b1 1.5) were consecutively exposed to an oral task (#2) and an arithmetic task (#3) (Trier Social Stress Test for Children (TSST-C)), lasting 5 min each, and a three-minute cellular phone call (#4). Salivary cortisol (SC) was sampled at baseline (#1) and immediately after each exposure (#2, 3, and 4). Baseline serum high-sensitivity C-reactive protein (hsCRP) and cortisol levels were also assessed. ANS dynamics and complexity were measured using Sample Entropy (SampEn) at each experimental time period (#1\u20134). Baseline serum hCRP and cortisol correlated negatively to each other, while the ANS and HPA axis acute reactions to the three consecutive stimuli differed over time. The ANS adaptation to these stimuli included complexity modulation, which was not dependent on baseline hsCRP or cortisol, and weakened during the third stimulation. However, baseline hsCRP and cortisol had a weakening and an increasing effect on the HPA axis over time, respectively. We conclude that low-level inflammation and baseline morning cortisol level have no effect on ANS dynamics but influence the HPA axis response to consecutive external stimuli.<\/jats:p>","DOI":"10.3390\/children10020248","type":"journal-article","created":{"date-parts":[[2023,1,30]],"date-time":"2023-01-30T04:31:27Z","timestamp":1675053087000},"page":"248","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Neuroendocrine System Adaptation during Consecutive Extrinsic Stimuli: A Pilot Dynamic Study"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1227-5274","authenticated-orcid":false,"given":"Styliani A.","family":"Geronikolou","sequence":"first","affiliation":[{"name":"Clinical, Translational Research and Experimental Surgery Centre, Biomedical Research Foundation of the Academy of Athens, 4, Soranou Ephessiou Str., 11527 Athens, Greece"},{"name":"First Department of Pediatrics, National and Kapodistrian University of Athens Medical School, \u201cAghia Sophia\u201d Children\u2019s Hospital, Thivon 1, 11527 Athens, Greece"},{"name":"University Research Institute of Maternal and Child Health and Precision Medicine, National and Kapodistrian University of Athens Medical School, Levadias 8, 11527 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vasilis","family":"Vasdekis","sequence":"additional","affiliation":[{"name":"Department of Statistics, Athens University of Economics and Business, Kodrigtonos 12, 11257 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aimilia","family":"Mantzou","sequence":"additional","affiliation":[{"name":"First Department of Pediatrics, National and Kapodistrian University of Athens Medical School, \u201cAghia Sophia\u201d Children\u2019s Hospital, Thivon 1, 11527 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0321-7569","authenticated-orcid":false,"given":"Constantinos","family":"Davos","sequence":"additional","affiliation":[{"name":"Clinical, Translational Research and Experimental Surgery Centre, Biomedical Research Foundation of the Academy of Athens, 4, Soranou Ephessiou Str., 11527 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dennis V.","family":"Cokkinos","sequence":"additional","affiliation":[{"name":"Clinical, Translational Research and Experimental Surgery Centre, Biomedical Research Foundation of the Academy of Athens, 4, Soranou Ephessiou Str., 11527 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3098-5264","authenticated-orcid":false,"given":"George P.","family":"Chrousos","sequence":"additional","affiliation":[{"name":"Clinical, Translational Research and Experimental Surgery Centre, Biomedical Research Foundation of the Academy of Athens, 4, Soranou Ephessiou Str., 11527 Athens, Greece"},{"name":"First Department of Pediatrics, National and Kapodistrian University of Athens Medical School, \u201cAghia Sophia\u201d Children\u2019s Hospital, Thivon 1, 11527 Athens, Greece"},{"name":"University Research Institute of Maternal and Child Health and Precision Medicine, National and Kapodistrian University of Athens Medical School, Levadias 8, 11527 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1056\/NEJM199801153380307","article-title":"Protective and damaging effects of stress mediators","volume":"338","author":"McEwen","year":"1998","journal-title":"N. 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