PR000380 (Project)

Description:Endurance exercise in horses implies adaptive processes involving affective, physiological, biochemical, and cognitive-behavioral response in an attempt to regain homeostasis. We hypothesized that the identification of the relationships between blood metabolome, transcriptome and miRNome during endurance exercise could provide significant insights into the molecular response to intense exercise or prediction of this response at basal status. In this perspective, the serum metabolome and whole-blood transcriptome and miRNome data were obtained from 10 horses before and after a 160 km endurance competition. Results: We obtained a global regulatory network based on 11 unique metabolites, 263 metabolic genes and 5 miRNAs whose expression was significantly altered at T1 (post- endurance competition) relative to T0 (baseline, pre- endurance competition). This network provided new insights into the cross talk between the distinct molecular pathways (e.g. energy and oxygen sensing, oxidative stress, and inflammation) that were not detectable when analyzing single metabolites or transcripts alone. This suggested that single metabolites and transcripts were carrying out multiple roles and thus sharing several biochemical pathways. Using a regulatory impact factor metric analysis, this regulatory network was further confirmed at the transcription factor and miRNA levels. In an extended cohort of 39 animals, multiple factor analysis confirmed the strong associations between lactate, methylene derivatives, miR-21-5p, miR-16-5p, and genes that coded proteins involved in metabolic reactions primarily related to energy, ubiquitin proteasome and lipopolysaccharide immune responses at T1. Multiple factorial analyses also identified potential biomarkers at T0 for an increased possibility of failure to finish an endurance competition.