Inflammatory biomarker, neopterin, predominantly enhances myelopoiesis, which suppresses erythropoiesis via activated stromal cells.
Neopterin is produced by monocytes and is a useful biomarker for inflammation. We found previously that neopterin enhanced myelopoiesis but suppressed B-lymphopoiesis triggered by the positive and negative regulations of cytokines produced by stromal cells in mice. The effects of neopterin on erythropoiesis during the enhancement of myelopoiesis were determined in the present study using C57BL/6J mice. The intravenous injection of neopterin into mice resulted in a prolonged decrease in the number of femoral erythroid progenitor cells (BFU-Es and CFU-Es), whereas the number of femoral myeloid progenitor cells (CFU-GMs) was increased. Interestingly, the oscillatory changes in the number of erythroid progenitor cells were reciprocal to those of myeloid progenitor cells. The expression of Cdc42, a regulator of the balance between erythropoiesis and myelopoiesis, was down-regulated, implying that the suppression of erythropoiesis is due to myelopoietic predominance. Furthermore, the expression of SDF-1 in stromal cells, a negative regulator of erythropoiesis, was up-regulated. These results suggest that neopterin facilitates myelopoiesis in the bone marrow by suppressing erythropoiesis, thereby contributing to the potential up-regulation of inflammatory process.
Tsuboi
Isao
I
Department of Functional Morphology, Nihon University School of Medicine, 30-1 Ohyaguchi-kami-machi, Itabashiku, Tokyo 173-8610, Japan. tsuboi@med.nihon-u.ac.jp
Harada
Tomonori
T
Hirabayashi
Yoko
Y
Kanno
Jun
J
Inoue
Tohru
T
Aizawa
Shin
S
D000818:Animals; D015415:Biomarkers; D001854:Bone Marrow Cells / Q000166:cytology / Q000378:metabolism*; D002452:Cell Count; D002478:Cells, Cultured; D054377:Chemokine CXCL12 / Q000378:metabolism; D015672:Erythroid Precursor Cells / Q000166:cytology / Q000378:metabolism*; D004920:Erythropoiesis / Q000235:genetics; D005260:Female; D005786:Gene Expression Regulation; D055014:Granulocyte-Macrophage Progenitor Cells / Q000166:cytology / Q000378:metabolism*; D007249:Inflammation / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D038042:Myelopoiesis / Q000235:genetics; D019798:Neopterin / Q000276:immunology* / Q000494:pharmacology; D017154:Stromal Cells / Q000276:immunology*; D020764:cdc42 GTP-Binding Protein / Q000378:metabolism
D015415:Biomarkers; D054377:Chemokine CXCL12; C515256:Cxcl12 protein, mouse; D019798:Neopterin; D020764:cdc42 GTP-Binding Protein