OBJECTIVETo observe the role of Panax notoginosides (PNS) in up-regulation of GATA family transcription factors, and explore intracellular signal pathway of PNS in the proliferation of hematopoietic cells.

METHODSHuman bone marrow cells were incubated with different concentrations of PNS for colony-forming assay. Human cell lines HL-60, K562, CHRF-288 and Meg-01 were incubated with PNS (10 mg/L) for 14 days. The cell nuclear proteins were extracted and analyzed by Western blot with antibodies against GATA-1, GATA-2. Electrophoretic mobility shift assay (EMSA) and antibody gel supershift assay was performed using (32)P labeled GATA consensus oligonucleotide which contains binding site for GATA transcription factors.

RESULTSPNS could promote the proliferation of CFU-GM and CFU-E and induce the expression of GATA-1, GATA-2. The nuclear proteins of both GATA-1 and GATA-2 in K562, CHRF-288 and Meg-01 cells treated by PNS were increased by (1.5 - 2.8) and (2.0 - 3.1)-fold over untreated cells respectively. GATA binding activity initiated by PNS was apparently elevated to form higher density band of GATA-DNA complex. While there was no detectable change in HL-60 cells before and after PNS treatment. The predominant GATA binding complex was mainly attributable to both GATA-1 and GATA-2 proteins being in phosphorylated status.

CONCLUSIONPNS can induce the synthesis of transcription factors GATA-1 and GATA-2 and enhance their DNA binding activity, which could play a role in the up-regulation of the expression genes related to proliferation and differentiation in hematopoietic cells.