Background. In high-altitude areas, hypoxic stress can elicit a series of physiological responses in humans. Exosomes play important roles in both local and distal cellular communications. Methods. We used ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) studies to analyze the differentially expressed metabolomics and proteomics in serum exosome of hypoxic preconditioning participants and control subjects in the hypoxic conditions. Results. Fifty-seven military personnel were divided into hypoxic preconditioning group ( n = 27 ) and control group ( n = 30 ). One hundred thirty-six differentially expressed serum exosomal metabolites were found between the hypoxic preconditioning and control groups in the hypoxic conditions, and these differentially expressed metabolites were enriched in pathways related to lysine degradation, butanoate metabolism, GABAergic synapse, histidine metabolism, and linoleic acid metabolism. In addition, hypoxic preconditioning participants showed 102 excellent differential expressions of proteomics compared to controls, which involved actin cytoskeleton organization, hemostasis, complement and coagulation cascades, vesicle-medicated transport, wound healing, etc. Conclusions. We revealed that the expression of exosomal metabolites and proteomics in hypoxic preconditioning participants was significantly different compared to controls in hypoxic conditions.

It remains unclear whether acute unpleasant exercise (AUE) caused by foot shocks leads to gastrointestinal (GI) mucosal injury and bleeding. In this study, we investigated the involvement of inflammatory cytokines in AUE-induced GI mucosal injury/bleeding and oxidative stress by analyzing the expressions of pro-inflammatory (IL-1β, IL-6, TNF-α, and iNOS) and anti-inflammatory (IL-10) cytokines in the hypothalamus and duodenum after foot shocks using PCR. Results showed that the expressions of IL-1β, IL-6, TNF-α, and iNOS were significantly increased following the process, while IL-10 was not activated. These findings suggest that the activation of inflammatory response system (IRS) is closely related to GI mucosal injury/bleeding and oxidative stress induced by AUE caused by foot shocks.