Chronic Hypobaric Hypoxia Stimulates Differential Expression of Cognitive Proteins in Hippocampal Tissue.

Objective: We aimed to determine changes in cognitive function resulting from chronic hypobaric hypoxia through proteomic analysis of hippocampal tissue. We screened cognition-related proteins to provide ideas and directions that could help prevent and treat hypoxia-associated cognitive impairment. Methods: We analyzed hippocampal tissues from mice exposed to high altitudes and control mice using 4 D label-free quantitative proteomics. The data were analyzed by protein quantitative analysis, functional annotation, differential protein screening, clustering analyses, and functional classification and enrichment. Differential protein expression was investigated using targeted quantitative omics based on parallel response monitoring. Results: We identified and quantified 20 target proteins in 12 samples, of which 18 were significant validated proteins that were or might be related to cognitive functions. Signaling pathways that were significantly enriched in differentially expressed proteins were pyrimidine metabolism, 5'-Adenosine Triphosphate-activated protein kinase signaling, phospholipase D signaling, purine metabolism, inflammatory mediator regulation of transient receptor potential channels, hedgehog signaling pathways, dilated cardiomyopathy, platelet activation, insulin resistance, mRNA surveillance pathways, drug metabolism-other enzymes, and drug metabolism-cytochrome P450. Conclusion: Chronic hypoxia alters protein expression in murine hippocampal tissues. Eighteen differentially expressed cognition-related proteins might be related to cognitive impairment in mice exposed to chronic high-altitude hypoxia.