Ginseng-Derived Panaxadiol Saponins Promote Hematopoiesis Recovery in Cyclophosphamide-Induced Myelosuppressive Mice: Potential Novel Treatment of Chemotherapy-Induced Cytopenias / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the potential efficacy of panaxadiol saponins component (PDS-C), a biologically active fraction isolated from total ginsenosides, to reverse chemotherapy-induced myelosuppression and pancytopenia caused by cyclophamide (CTX).</p><p><b>METHODS</b>Mice with myelosuppression induced by CTX were treated with PDS-C at a low- (20 mg/kg), moderate- (40 mg/kg), or high-dose (80 mg/kg) for 7 consecutive days. The level of peripheral white blood cell (WBC), neutrophil (NEU) and platelet (PLT) were measured, the histopathology and colony formation were observed, the protein kinase and transcription factors in hematopoietic cells were determined by immunohistochemical staining and Western blot.</p><p><b>RESULTS</b>In response to PDS-C therapy, the peripheral WBC, NEU and PLT counts of CTX-induced myelosuppressed mice were significantly increased in a dose-dependent manner. Similarly, bone marrow histopathology examination showed reversal of CTX-induced myelosuppression with increase in overall bone marrow cellularity and the number of hematopoietic cells (P<0.01). PDS-C also promoted proliferation of granulocytic and megakaryocyte progenitor cells in CTX-treated mice, as evidenced by significantly increase in colony formation units-granulocytes/monocytes and -megakaryocytes (P<0.01). The enhancement of hematopoiesis by PDS-C appears to be mediated by an intracellular signaling pathway, this was evidenced by the up-regulation of phosphorylated mitogen-activated protein kinase (p-MEK) and extracellular signal-regulated kinases (p-ERK), and receptor tyrosine kinase (C-kit) and globin transcription factor 1 (GATA-1) in hematopoietic cells of CTX-treated mice (P<0.05).</p><p><b>CONCLUSIONS</b>PDS-C possesses hematopoietic growth factor-like activities that promote proliferation and also possibly differentiation of hematopoietic progenitor cells in myelosuppressed mice, probably mediated by a mechanism involving MEK and ERK protein kinases, and C-kit and GATA-1 transcription factors. PDS-C may potentially be a novel treatment of myelosuppression and pancytopenia caused by chemotherapy.</p>

Screening the active constituents of Chinese medicinal herbs as potent inhibitors of Cdc25 tyrosine phosphatase, an activator of the mitosis-inducing p34cdc2 kinase / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

<p><b>OBJECTIVE</b>To screen and evaluate the active constituents of Chinese medicinal herbs as potent inhibitors of Cdc25 phosphatase.</p><p><b>METHODS</b>The affinity chromatography purified glutashione-S-transferase/Cdc25A phosphatase fusion protein and Cdc2/cyclin B from the extracts of starfish M phase oocytes are used as the cell cycle-specific targets for screening the antimitotic constituents. We tested 9 extracts isolated from the Chinese medicinal herbs and vegetables including the agents currently used in cancer treatment by measuring the inhibition of Cdc25A phosphatase and Cdc2 kinase activity. The antitumor activity of the extracts was also evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and flow cytometry.</p><p><b>RESULTS</b>Cdc25A inhibitory activity and antitumor activity are detected in the extracts isolated from three Chinese medicinal herbs Agrimona pilosa; Herba solani lyrati; Galla chinesis.</p><p><b>CONCLUSION</b>We found three extracts isolated from Chinese medicinal herbs have potential inhibitory activity of Cdc25 phosphatase using a highly specific mechanism-based screen assay for antimitotic drug discovery.</p>