AN EVIDENCE BASED COUNTERMEASURE FOR SPACE FLIGHT: NUTRITIONAL NUCLEOTIDE AUGMENTATION OF IMMUNITY

摘要

Spaceflight invokes numerous biological stressors that affect several human physiological systems. Some of these effects may be the result of exposure to the environment of space flights (microgravity, cosmic radiation) or the result of psychoneuroendocrine changes due to physical and psychological stresses involved in spaceflight. Microgravity and stressrnexperienced during space flights results in immune system aberration with decrease in immune function. Preliminary studies in the investigators laboratory documented in two ground-based models (1- mouse hind limb weight unloading model and 2- cell culture in clinostatic bioreactor) that dietary and supplemental nucleotides (NT) restore immune function (Kulkarni et al 2002, Hales et al 2002, Yamauchi et al 2002).rnExisting evidence suggests that space travelers are immunosuppressed, presumably by microgravity environment stressors. Immune-suppression puts space travelers at risk for adverse effects such as infection and cancer by the conditions in their new environment. Maintenance of a healthy immune system goes beyond resistance to infection and it is essential in the homeostasis required for resistance to neoplastic disease, for prevention of autoimmune disease, and tissue repair and wound healing. This report summarizes our observations so far and further documents (Fig. 1) the feasibility of a true countermeasure (CM) for the adverse effects on immune system in microgravity.