If we used higher doses of irradiation the mice will die around day 14 after irradiation due to the development of hematopoietic syndrome

If we used higher doses of irradiation the mice will die around day 14 after irradiation due to the development of hematopoietic syndrome. an anti-ferroptosis radiation mitigator which can mitigate radiation alone or in combination with an anti-apoptosis agent JP4-030 or an anti-necroptosis agent necrostatin [12]. Metformin was the other radiation mitigator we used [24,25,26]. Metformin has antioxidant activity which has been shown to protect normal tissue from irradiation while at the same time making tumor cells more sensitive to irradiation [24,25,26]. 2. Results 2.1. Effect of Gavage of LR-IL-22 on the Ionizing Irradiated Intestine We constructed a paradigm for delivery of whole abdomen irradiation (WAI) followed by gavage of LR-IL-22 alone or combined with systemic administration of each of two small molecule Oxolamine citrate radiation mitigators. The paradigm for administration is outlined in (Figure 1). Both total body irradiation (9.25 Gy) and WAI (15.75 Gy) Oxolamine citrate damage intestinal endothelial cells. At 24 h, there was clearly destruction of the endothelial cells in the ileum following Oxolamine citrate 9.25 Gy TBI (Figure 2A). In the irradiated intestine there were fewer CD31 positive endothelial cells and decreased microvasculature compared to the ileum of the control mice which had more CD31 positive cells with an intact microvasculature. Scanning electron microscopy (SEM) following 15.75 Gy WAI revealed that there was damage to the lamina propria (Figure 2B). While the irradiation dose of 15.75 Gy WAI clearly damaged the intestinal microvasculature, the gavage of LR-IL-22 but not control LR ameliorated the damage (Figure 2B). The magnification of areas of the intestinal villus demonstrated integrity of microvascular endothelial cells (CD31+) in those animals receiving LR-IL-22 at 24 h after WAI compared to those receiving radiation alone. SEM of areas of the villus demonstrated damage to not only the lamina propria by 15.75 Gy WAI but also to the other cells in the villus as seen by cellular swelling in the cells, but preservation of the integrity of this anatomic area by gavage of LR-IL-22, but not LR (Figure 2B). Open in a separate window Figure 1 Experimental Paradigm: Small molecule radiation mitigator and probiotic LR-IL-22 administration prior to and following 15.75 Gy WAI. Small molecule mitigators utilized in survival studies include intramuscular Baicalein administered 15 min prior to WAI and 24 h following WAI, Metformin administered orally in drinking water for 7 day following WAI and LR-IL-22 gavaged 24 h following WAI. Open in a separate window Figure 2 Effect of 9.25 Gy total body irradiation (TBI) or 15.75 Gy Oxolamine citrate whole abdomien irradiation (WAI) observed as destruction of microvascular endothelial cells and cell swelling of the lamina propria including the intestinal multivasculature in the intestinal crypts. (A) Control mouse ileum and at 24 h after 9.25 Gy irradiation: Inserts are green = CD31 positive endothelial cells, red = collagen and blue = DAPI (100). (B) Electron micrographs of intestinal villi at 48 h after 15.75 Gy WAI showing cell swelling of lamina propria (1000). Both 9.25 Gy TBI and 15.75 Gy WAI Cd33 cause destruction of microvascular endothelial cells and cellular Oxolamine citrate swelling of the lamina propria including the intestinal multivasculature within the crypts. The red line in 2B shows the division of the intestinal villus cells from underlying lamina propria. 2.2. LR-IL-22 Produces Variable Alterations in Intestinal and Plasma Inflammatory Cytokines We next evaluated the effects of LR-IL-22 oral gavage alone or in combination with intramuscular (I.M.) administration of a systemic radiation mitigator including.