Is spaceflight-induced immune dysfunction linked to systemic changes in metabolism?

Area of Science:

• Space biology
• Immunology
• Metabolomics

Background:

• The final Space Shuttle mission (STS-135) provided an opportunity to study spaceflight effects on biological systems.
• Mice were utilized as a model organism to investigate physiological changes during space travel.

Purpose of the Study:

• To characterize the effects of spaceflight on immune cell phenotype, adrenal gland hormones, and liver gene/metabolite profiles.
• To investigate potential links between immune function and metabolic alterations induced by spaceflight.

Main Methods:

• Analysis of splenic leukocyte subsets and phagocytic function.
• Measurement of catecholamine and corticosterone levels in adrenal glands.
• Transcriptomic and metabolomic profiling of liver tissue.
• Comparison of spaceflight samples with ground controls.

Main Results:

• Decreased splenic leukocyte subsets but increased reactive oxygen species (ROS)-related activity.
• Elevated corticosterone levels in adrenals and liver, with no significant change in catecholamines.
• Gene expression and metabolomic data suggested increased phagocytic activity and fatty acid oxidation, with decreased glycolysis, not indicative of oxidative or psychological stress.

Conclusions:

• Spaceflight induces complex changes in immune and metabolic functions in mice.
• The findings suggest a potential link between immune and metabolic dysregulation during spaceflight, similar to ground-based diseases.
• Further research is needed to understand the mechanisms behind these spaceflight-induced adaptations.