Effects of notoginosides on proliferation and upregulation of GR nuclear transcription factor in hematopoietic cells.
OBJECTIVE
To investigate the effects of panax notoginosides (PNS) on the proliferation of human hematopoietic stem/progenitor cells, and to explore the signaling pathway of the nuclear transcription factor of the glucocorticoid receptor (GR-NTF) initiated by PNS related with the proliferation.


METHODS
The human CD34+ cells and bone marrow nuclear cells were exposed to PNS at a concentration of 0, 10, 25, 50, and 100 mg/L, respectively, in semi-solid culture system to observe colony forming unite of all lineages, granulocyte, erythrocyte, and megakaryocyte (CFUGEMM, CFU-GM, CFU-E, and CFU-MK). Three lineages of human hematopoietic cell lines, including granulocytic HL-60, erythrocytic K562, megakaryocytic CHRF- 288, and Meg-01 cells were incubated with PNS at 20 mg/L for 14 d. Meanwhile, dexamethasone (Dex) was used as a positive control. The nuclear protein of the cells was analyzed by Western blotting with monoclonal antibodies against the amino or carboxyl terminus of GR-NTF. Electrophoretic mobility shift assay performed by using the 32P-radiolabeled GR-NTF consensus oligonucleotide.


RESULTS
PNS promoted the proliferation of CD34+ cells and significantly raised the colony numbers of CFU-GEMM by 34.7%+/-16.0% over the non-PNS control (P<0.01). PNS also enhanced the proliferation of CFU-GM, CFU-E, and CFU-MK by 39.3%+/- 5.7%, 33.3%+/-7.3%, and 26.2%+/-3.2%, respectively. GR-NTF protein levels of either the amino or carboxyl terminus in K562, CHRF-288, and Meg-01 treated by PNS increased by 2.4-2.8 fold and 1.3- 3.9 fold over the untreated cells. GR-NTF binding activity, initiated by either PNS or Dex, was apparently elevated to form the complex of GR-NTF with DNA as higher density bands in K562 and CHRF-288 cells, and some activity appeared as a band in HL-60 cells induced by PNS.


CONCLUSIONS
PNS displayed the action of hematopoietic growth factor-like or synergistic efficacy to promote proliferation of human progenitor cells, may play a role in the upregulation of gene expression related to proliferation of hematopoietic cells through increasing the GR-NTF synthesis and its DNA binding activity.
Gao
Rui-Lan
RL
Hematology Institution, The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310006, China. zphtcmcn@mail.hz.zj.cn
Chen
Xiao-Hong
XH
Lin
Xiao-Jie
XJ
Qian
Xu-Dai
XD
Xu
Wei-Hong
WH
Chong
Beng Hock
BH
D000818:Animals; D018952:Antigens, CD34 / Q000378:metabolism; D001854:Bone Marrow Cells / Q000166:cytology / Q000502:physiology; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D006801:Humans; D053723:Panax notoginseng / Q000737:chemistry; D011965:Receptors, Glucocorticoid / Q000235:genetics / Q000378:metabolism*; D012503:Saponins / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation / Q000187:drug effects
D018952:Antigens, CD34; D011965:Receptors, Glucocorticoid; D012503:Saponins; D014157:Transcription Factors