The Up-regulation Of Nuclear Transcription Factor Of Glucocorticoid Receptor Induced By Panaxadiol Saponin & Panax Notoginosides In Hematopoietic Cells

Objective To observe the action of both Panaxadiol Saponin (PDS) and Panax Notoginosides (PNS) on nuclear transcription factor of Glucocorticoid receptor (GR) by virtue of signaling pathway of Glucocorticoid, and to explore up-regulation of genes expression in relationship with proliferation initiated by PDS and PNS in the hematopoietic cells.Methods Three lineage lines of human myeloid HL-60, erythroid K562, megakaryoid CHRF-288 and Meg-01 cells were incubated in the presence of PDS or PNS for 14 days. The nuclear protein of cells were extracted and analyzed by Western blot with monoclonal antibodies against GR (E-20) or GR (P-20). Electrophoretic mobility shift assay (EMSA) was employed by using 32P radio labeled GR consensus oligonucleotide which contained binding site for GR nuclear transcription factors.Results (1)The nuclear transcription factors of GR could be induced by PDS. Western Blot showed that the nuclear protein of GR (E-20) and GR (P-20) in three cell lines of K562, CHRF-288 and Meg-01 treated by PDS were increased by 2.4~5.7 fold and 1.5~3.3 fold over untreated cells respectively. (2)The nuclear transcription factors of GR could be inducedby PNS. The levels of both GR (E-20) and GR (P-20) nuclear transcription factors were 2.4~2.8 fold and 1.3-3.9 fold respectively more than those of non-PNS in three cell lines of K562, CHRF-288 and Meg-01. While there was no detectable difference in HL-60 cells after being treated by PDS or PNS. (3) PDS could raise the DNA binding activity of GR protein. EMSA results showed that the band density of GR-DNA complex from HL-60, K562 and CHRF-288 cells treated by PDS was obviously higher than that of non-PDS. (4) PNS also could enhance the DNA binding activity of GR protein. The GR binding activity initiated by PNS were apparently elevated to form higher density band of GR-DNA complex in both K562 and CHRF-288. There was somewhat of activity appeared as a band in HL-60 cells induced by PNS although no detectable activity without treatment.Conclusion The action of both PDS and PNS on hematopoietic proliferation was involved in nuclear transcription factor of GR. They could play the role in the up-regulation of genes expression related to proliferation on hematopoietic cells through increasing the synthesis and DNA binding activity of GR. The action of PDS, PNS on GR transcription factor as showed above was resembled to Glucocorticoid.