{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T09:28:03Z","timestamp":1785403683955,"version":"3.56.0"},"reference-count":47,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,6,13]],"date-time":"2026-06-13T00:00:00Z","timestamp":1781308800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003554","name":"Lundbeck Foundation","doi-asserted-by":"publisher","award":["R324-2019-1470"],"award-info":[{"award-number":["R324-2019-1470"]}],"id":[{"id":"10.13039\/501100003554","id-type":"DOI","asserted-by":"publisher"}]},{"award":["R324-2019-1470"],"award-info":[{"award-number":["R324-2019-1470"]}],"id":[{"id":"https:\/\/ror.org\/03hz8wd80","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005747","name":"A.P. M\u00f8ller Foundation","doi-asserted-by":"crossref","award":["19-L-0275"],"award-info":[{"award-number":["19-L-0275"]}],"id":[{"id":"10.13039\/501100005747","id-type":"DOI","asserted-by":"crossref"}]},{"award":["19-L-0275"],"award-info":[{"award-number":["19-L-0275"]}],"id":[{"id":"https:\/\/ror.org\/03kkzdv75","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002808","name":"Carlsberg Foundation","doi-asserted-by":"publisher","award":["CF21-0605"],"award-info":[{"award-number":["CF21-0605"]}],"id":[{"id":"10.13039\/501100002808","id-type":"DOI","asserted-by":"publisher"}]},{"award":["CF21-0605"],"award-info":[{"award-number":["CF21-0605"]}],"id":[{"id":"https:\/\/ror.org\/01kpjmx04","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Metabolites"],"abstract":"<jats:p>Background\/Objectives: Cardiac regenerative ability varies in vertebrates. Adult mammals cannot mount a regenerative response, while fetal mammals and some salamanders and teleosts fully regenerate the heart after a cryoinjury mimicking a myocardial infarction. This contrast is suggested to be regulated in part by metabolism, with high regenerative capacity correlating with a comparatively lower mass-specific metabolic rate, ectothermy rather than endothermy and a metabolic phenotype favoring glycolysis in cardiac muscle. Methods: In this physiological study on axolotl salamanders, we altered the housing temperatures from the standard 20 \u00b0C to 10 \u00b0C, 25 \u00b0C and 30 \u00b0C and assayed key metabolic parameters as well as cardiac function, survival and regenerative capacity. Results: Our study demonstrated that while axolotls could be housed at temperatures ranging from 10 \u00b0C to 30 \u00b0C in an uninjured state, signs of a pathological response involving cardiac and metabolic insufficiency and mortality, especially after cryoinjury, increased progressively with increasing temperatures. We observed several metabolic effects, including differences in oxygen consumption, plasma metabolites and cardiac function. Cardiac regeneration after cryoinjury progressed as expected with only a small remaining injury after 60 days at the standard housing temperature of 20 \u00b0C. Regeneration was highly reduced in a reversible manner at 10 \u00b0C while regenerative rate was not affected at 25 \u00b0C. At 30 \u00b0C, cardiac regeneration could not be evaluated as the majority of animals (five out of six) did not survive the injury, likely reflecting insufficient cardiac reserve capacity to simultaneously sustain thermal metabolic effects and support tissue repair. Conclusions: The ectothermic axolotl undergoes several metabolic changes when exposed to different housing temperatures, with heart regeneration showing a narrower permissive temperature range than survival of the axolotl in an uninjured state.<\/jats:p>","DOI":"10.3390\/metabo16060414","type":"journal-article","created":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T05:59:47Z","timestamp":1781503187000},"page":"414","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Temperature-Dependent Modulation of Cardiac Metabolism, Post-Injury Survival and Regenerative Rate in Axolotls"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-1793-8106","authenticated-orcid":false,"given":"Anita","family":"Dittrich","sequence":"first","affiliation":[{"name":"Comparative Medicine Lab, Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sofie Amalie","family":"Andersson","sequence":"additional","affiliation":[{"name":"Comparative Medicine Lab, Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0084-9122","authenticated-orcid":false,"given":"Aage Kristian Olsen","family":"Alstrup","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, Aarhus University, 8200 Aarhus, Denmark"},{"name":"Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-7286-0653","authenticated-orcid":false,"given":"Pernille Lajer","family":"S\u00f8rensen","sequence":"additional","affiliation":[{"name":"Comparative Medicine Lab, Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mette Irene Theilgaard","family":"Simonsen","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, Aarhus University, 8200 Aarhus, Denmark"},{"name":"Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maibritt Hald","family":"Arildsen","sequence":"additional","affiliation":[{"name":"Comparative Medicine Lab, Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rasmus Roost","family":"Aabling","sequence":"additional","affiliation":[{"name":"Comparative Medicine Lab, Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8833-4456","authenticated-orcid":false,"given":"Henrik","family":"Lauridsen","sequence":"additional","affiliation":[{"name":"Comparative Medicine Lab, Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"22","DOI":"10.1038\/s41536-017-0027-y","article-title":"Heart regeneration in the salamander relies on macrophage-mediated control of fibroblast activation and the extracellular landscape","volume":"2","author":"Godwin","year":"2017","journal-title":"npj Regen. 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