PR001288 (Project)

Description:Investigating the metabolic effects of radiation is critical to understand the impact of radiotherapy (e.g., for bone marrow irradiation prior to hematopoietic stem cell transplantation in the clinic or in laboratory studies), space travel, and exposure to environmental radiation. In patients undergoing hemopoietic stem cell transplantation, iron overload is a common risk factor for poor outcomes. Previous studies assert that both irradiation and iron independently modulate tryptophan and indole metabolism of the microbiome, which may in turn impact host immune response. However, no studies have interrogated the multi-organ effects of these treatments concurrently. Herein, we use a model that recapitulate transfusional iron overload, a condition often observed in chronically transfused patients with thalassemia, sickle cell disease, or myelodysplastic syndrome. We applied an omics approach to investigate the impact of both iron load and irradiation on the host metabolome. Our results revealed dose-dependent effects of irradiation in red blood cells (RBC), plasma, spleen, and liver energy and redox metabolism. Increases in polyamines and purine salvage metabolites were observed in organs with high oxygen consumption including the heart, kidney, and brain. Irradiation also impacted the metabolism of the duodenum, colon, and stool, suggesting a potential effect on the microbiome. Iron infusion affected the respose to radiation in the organs and blood, especially in RBC polyamine metabolism and spleen antioxidant metabolism, and affected glucose, sulfur (especially methionine and glutathione systems) and tryptophan metabolism in the liver, stool, and brain. Together, the results suggest that radiation impacts metabolism on a multi-organ level with a significant interaction of host iron status.