Mesenchymal stem cells improve survival in a mice model of severe pneumococcal pneumonia

Abstract

Effects of lipopolysaccharide on RBC alteration in mice endotoxemic model Seolju Park, Jeihak Myung, Yeonhee Kim, Sungmook Yoo, Jaekwan Lim, Choonhak Lim Korea University Anam Hospital, Republic of Korea Korea University Ansan Hospital, Republic of Korea Korea University Medicine Graduate School, Republic of Korea Korean Artificial Organ Research Center, Republic of Korea Background/Purpose: Sepsis is a complex pathophysiological process that involves both alterations in the microcirculation (vessels with a diameter b100 m) and changes in the biochemical and physiological characteristics of the blood constituents. Alterations in RBC rheology participate in the alterations of the microcirculation. Early alterations of RBC rheology are reported to be seen commonly in the septic patients. However, time course of RBC alterations is not revealed. Therefore, we evaluated the change of RBC deformability and RBC aggregation in the mice endotoxemic model using lipopolysaccharide (LPS). Methods: Six-week-old male BALB/c mice were used in this study. The LPS-induced sepsis mice received LPS (20 mg/kg) intraperitoneally. Elongation indices (EIs) and aggregation indices (AIs) were tested at shear stresses of 1, 3, 7, 10, and 20 Pa for 0.5, 1, 2, 4, 6, 9, 12, and 24 hours after LPS. Results: There were no difference in AIs on 0.5, 1, 2, 4, 6, 9, 12, and 24 hours after LPS; however, EIs significantly decreased in only 10 and 20 Pa at 24 hours after LPS (P b .05). Conclusions: Our results suggested that change of RBC deformability was revealed on 24 hours after LPS injection, and choice of an appropriate shear stress may detect alterations of RBC deformability in LPS-induced sepsis mice.