Angelica sinensis polysaccharide promotes stress erythropoiesis in mice caused by 5-FU

Aim To investigate the effects of angelica sinensis polysaccharide (ASP) antagonizing 5-fluorouracil (5-FU) on spleen stress erythropoiesis in mice and its related mechanism. Methods C57BL/6J mice aged 6-8 weeks were randomly divided into control group, ASP group, 5-FU group and ASP+5-FU group. The mouse body weight during the modeling period was recorded, and peripheral blood routine and the number of mononuclear cells in the bone marrow of femur were measured. Histopathology of spleen was detected, also the index and cellularity of spleen were analyzed. BFU-E of spleen mononuclear cells was counted. The number of F4/80+ splenic macrophages was detected by flow cytometry. The expression levels of adhesion molecule genes Emp, iron transport genes including Hmox-1, Trf, Fpn and TrfR, endocytosis genes including Tim4 and MerTK were detected by qRT-PCR. Results ASP partially reversed the decrease of mice body weight, erythrocytes number, hemoglobin content, hematocrit and the cellularity of bone marrow mononuclear cells induced by 5-FU. ASP increased spleen volume, spleen index, red pulp area, the number of splenocytes, and promoted spleen BFU-E formation. ASP antagonizing 5-FU, maintained the number of F4/80+ splenic macrophages, and up-regulated the gene expression of Emp, Hmox-1, Trf, Fpn, TrfR, Tim4 and MerTK. Conclusions ASP promotes stress erythropoiesis in spleen of mice by protecting the number and function of central macrophages of splenic erythroblast islands.