RESUMEN
Acute high-altitude illness seriously threatens the health and lives of people who rapidly ascend to high altitudes, but there is currently no particularly effective method for the prevention or treatment of acute high-altitude illness. In the present study, we found that fasting preconditioning effectively improved the survival rate of rats exposed to a simulated altitude of 7620 m for 24 h, and a novel animal model of rapid adaptation to acute hypoxia was established. Compared with control treatment, fasting preconditioning activated AMPK, induced autophagy, decreased ROS levels, and inhibited NF-κB signaling in the cardiac tissues of rats. Our results suggested that fasting effectively improved the acute hypoxia tolerance of rats, which was gradually enhanced with prolongation of fasting. In addition, the acute hypoxia tolerance of young rats was significantly higher than that of adult rats. These experimental results lay the foundation for achieving rapid adaptation to acute hypoxia in humans.
Asunto(s)
Adaptación Fisiológica/fisiología , Envejecimiento/fisiología , Ayuno/fisiología , Hipoxia/fisiopatología , Proteínas Quinasas Activadas por AMP/metabolismo , Factores de Edad , Animales , Autofagia , Western Blotting , Estimación de Kaplan-Meier , Masculino , Proteínas de la Membrana/metabolismo , Microscopía Electrónica de Transmisión , Proteínas Mitocondriales/metabolismo , Miocardio/citología , Miocardio/metabolismo , Miocardio/ultraestructura , FN-kappa B/metabolismo , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Transducción de SeñalRESUMEN
This study examined the effects of hypoxemia caused by acute high-altitude hypoxia (AHAH) exposure on the human intestinal flora and its metabolites. The changes in the intestinal flora, metabolism, and erythropoietin content in the AHAH population under altitude hypoxia conditions were comprehensively analyzed using 16S rRNA sequencing, metabonomics, and erythropoietin content. The results showed that compared with those in the control group (C group), the flora and metabolites in the hypoxemia group (D group) were altered. We found alterations in the flora according to the metabolic marker tyrosine through random forest and ROC analyses. Fecal and serum metabonomics analyses revealed that microbial metabolites could be absorbed into the blood and participate in human metabolism. Finally, a significant correlation between tyrosine and erythropoietin (EPO) content was found, which shows that human intestinal flora and its metabolites can help to confront altitude stress by regulating EPO levels. Our findings provide new insights into the adaptive mechanism and prevention of AHAH.