{"doi":"10.1093/milmed/usaf622","title":"Oxylipin Responses during the Yukon Arctic Ultra: The Longest and Coldest Ultramarathon in the World","abstract":"INTRODUCTION: Aerobic exercise and cold exposure modulate lipid mediator production, which may optimize physiological resilience. The Yukon Arctic Ultra (YAU), a 692-km self-provisioned multiday endurance event, offers a unique opportunity to examine lipidomic adaptations to nutrients and environmental and physical stress. This study aimed to identify lipid mediators responsive in YAU athletes compared to control participants. METHODS: Nine athletes and six controls were recruited from the 2017 and 2019 YAU events. Targeted liquid chromatography-tandem mass spectrometry/mass spectrometry-based signaling lipidomic analysis was conducted on serum samples collected from participants at pre-event, during the event, and post-event time points. RESULTS: Athletes and controls did not differ significantly in age, body mass index (BMI), fat mass index (FMI), or fat-free mass index. During the event, athletes exhibited significant reductions in BMI, fat mass, and FMI, whereas no changes were observed in controls. Athletes showed higher baseline levels of anti-inflammatory oxylipins, including resolvin D2 and lipoxin A4 (LXA4), and lower levels of the pro-inflammatory leukotriene E4 compared to controls. Linoleic acid- and α-linolenic acid-derived oxylipins were also elevated in athletes. Notably, these anti-inflammatory lipids remained elevated throughout the event. Certain hydroxy-eicosapentaenoic acids demonstrated a declining trend during the event in athletes. DISCUSSION: YAU athletes exhibit a distinct lipidomic signature marked by persistently elevated anti-inflammatory oxylipins, likely reflecting a complex interplay between adipose tissue and skeletal muscle. Overall, the oxylipin shifts point to anti-inflammatory and thermogenic adaptations that support physiological resilience during physical, nutrient, and environmental stress in austere circumstances.","journal":"Military Medicine","year":2025,"id":537778,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":1,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9519,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":344006,"name":"Tadataka Tsuji","orcid":"0000-0002-2837-8246","position":1,"is_corresponding":false},{"id":1424483,"name":"R. Lucas Thomas","orcid":null,"position":2,"is_corresponding":false},{"id":523818,"name":"Melynda S. Coker","orcid":"0000-0002-9019-6216","position":3,"is_corresponding":false},{"id":294956,"name":"Juan J. Aristizabal‐Henao","orcid":"0000-0002-2085-2396","position":4,"is_corresponding":false},{"id":1424484,"name":"Michael A Kiebish","orcid":null,"position":5,"is_corresponding":false},{"id":1424485,"name":"Camilla Kienest","orcid":null,"position":6,"is_corresponding":false},{"id":1424486,"name":"Adriane Schalt","orcid":null,"position":7,"is_corresponding":false},{"id":60610,"name":"Yu‐Hua Tseng","orcid":"0000-0003-2053-9559","position":8,"is_corresponding":false},{"id":1424034,"name":"Mathias Steinach","orcid":"0000-0002-7457-4301","position":9,"is_corresponding":false},{"id":523821,"name":"Robert H. Coker","orcid":"0000-0002-1037-9339","position":0,"is_corresponding":true}],"reference_count":27,"raw_metadata":null,"created_at":"2026-07-19T02:52:16.891390Z","pmid":"41525801","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}