title: Effects of neopterin on the hematopoietic microenvironment of senescence-accelerated mice (SAM).
abstract: The pteridine neopterin (NP) is produced by monocytes and is known to be a useful marker of immunological activation, although, it remains elusive whether neopterin itself exhibits biological functions. Recently, we found that NP stimulates hematopoietic cell proliferation and differentiation by activating bone marrow stromal cell function. In order to elucidate the biological effect of NP on stromal cells, its effects on hematopoiesis was determined in the mouse model of age-related stromal impairment, senescence-accelerated mice (SAMs). An intraperitoneal administration of NP increased the number of peripheral leukocytes and CFU-GM in the bone marrow and spleen of young SAMs, however, no increase of CFU-GM in old SAMs (stromal impairment) was observed when compared with young SAMs. NP also increased the CFU-GM colony formation of bone marrow and spleen cells from young SAMs in a soft agar culture system, but it did not enhance CFU-GM colony formation of cells from old SAMs cultured in this system. Treatment with NP induced the production of hematopoietic stimulating factors, including IL-6 and GM-CSF, by bone marrow stromal cells from young SAMs but stromal cells from old SAMs did not respond to NP stimulation. Further studies will be required to clarify the mechanism by which NP stimulates the production of hematopoietic growth factors from stromal cells, the results of this study indicate that NP is a potent hematopoietic regulatory factor by activating stromal cell function(s).
authors.affiliation: Department of Internal Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Emiko
authors.initials: E
authors.lastname: Kanbe
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Hatta
authors.forename: Isao
authors.initials: I
authors.lastname: Tsuboi
authors.forename: Tomonori
authors.initials: T
authors.lastname: Harada
authors.forename: Morimichi
authors.initials: M
authors.lastname: Koshinaga
authors.forename: Tohru
authors.initials: T
authors.lastname: Inoue
authors.forename: Shin
authors.initials: S
authors.lastname: Aizawa
mesh_terms: D000375:Aging / Q000235:genetics*; D000818:Animals; D001854:Bone Marrow Cells / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000096:biosynthesis; D006410:Hematopoiesis / Q000187:drug effects*; D006412:Hematopoietic Stem Cells / Q000187:drug effects*; D015850:Interleukin-6 / Q000096:biosynthesis; D008297:Male; D051379:Mice; D008806:Mice, Inbred AKR; D019798:Neopterin / Q000494:pharmacology*; D013154:Spleen / Q000166:cytology / Q000187:drug effects; D013234:Stem Cells / Q000187:drug effects; D017154:Stromal Cells / Q000187:drug effects
chemical_list: D015850:Interleukin-6; D019798:Neopterin; D016178:Granulocyte-Macrophage Colony-Stimulating Factor