Study on the effect of vibsane-type diterpenoids of Viburnum odoratissimum on human HepG2 cell growth and its underlying mechanism / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To study the antiproliferation effect on HepG2 cells and its underlying mechanism of the active chemical composition of the Viburnum Odoratissimum.</p><p><b>METHODS</b>3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) reduction assay and trypan blue dye exclusion assay were used to assess the effect of vibsane-type diterpenoids on the proliferation of various tumor cells. Alterations in cell cycle and apoptosis were determined by flowcytometry. The enzymatic activity of caspase-3/7 was measured by Apo-ONE homogeneous Caspase-3/7 Assay kit.</p><p><b>RESULTS</b>Compound 1 #, a vibsane-type diterpenoid, was found to significantly inhibit the growth of HepG2 cells by anticancer proliferation activity screening. It was demonstrated that the modified groups on side chain coupled to C11 site affected the cell growth-inhibition activity of compounds by structure-activity analysis. In addition, HepG2 cell line was most sensitive to compound 1 #, which induced growth arrest of HepG2 cells in a dose- and time-dependent manner. Study on the mechanisms underlying these effects indicated that compound 1 # induced significant G0/G1 phase arrest of HepG2 cells in a time- and concentration-dependent manner. Meanwhile, It was found that higher concentrations of compound (5-10 micromol/L) caused evident increase in the unmber of apoptotic cells and dose-dependent activation of caspase-3/7.</p><p><b>CONCLUSION</b>Vibsane-type diterpenoids could significantly inhibit the growth of HCC HepG2 cells. Induction of cell cycle arrest and apoptosis may play important roles in their anticancer effects.</p>

Protective effects of WR2721 on early bone marrow hematopoietic function in mice exposed to 6.5 Gy of (60)Co γ-rays / 中国实验血液学杂志

The aim of this study was to investigate the effect of WR2721(amifostine) against bone marrow hematopoietic damage of mice exposed to 6.5 Gy of (60)Co-γ ray. A total of 60 C57/BL6J mice was divided into 3 groups:normal group (mice were injected with physiological salt solution), irradiation group (mice were injected with physiologic salt solution before irradiation) and WR2721 group (mice were injected with WR2721 before irradiation). The WBC, neutrophil (Neut), Plt and RBC levels in peripheral blood of 3 group mice were counted within 60 days after irradiation; the bone marrow nuclear cells (BMNC) were counted at 2 and 24 hours after irradiation; the hematopoietic stem/progenitor cell (LK/LSK) level and colony formation capability were detected by flow cytometry at 2 and 24 hours after irradiation. The results indicated that the counts of WBC and neut at 4 and 18 days, Plt at 7-18 days and RBC at 10-30 day after irradiation in WR2721 group were higher than those in irradiation group (P < 0.05); the BMNC, LSK and LK levels obviously increased at 24 hours after irradiation (P < 0.05), the CFU-GEMM, CFU-GM, CFU-MK BFU-E and CFU-E all significantly increased at 2 and 24 hours after irradiation (P < 0.01), as compared with irradiation group. It is concluded that WR2721 can effectively alleviate early hematopoietic damage and promote the fast recovery of peripheral blood cells in mice exposed to γ-ray, suggesting that the WR2721 has significant radioprotective effect on hematopoietic system.

High dose granulocyte colony-stimulating factor enhances survival and hematopoietic reconstruction in canines irradiated by 2.3 Gy mixed fission neutron and gamma ray / 中国实验血液学杂志

This study was purposed to evaluate the effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on hematopoietic reconstruction and survival in beagles exposed to mixed fission neutron and γ-ray. 13 beagles were unilaterally exposed to single dose of 2.3 Gy 90% neutrons. The experiments were divided into 3 groups: irradiation control group (no any treatment, n = 4), supportive care group (n = 5) and rhG-CSF plus supportive care group (n = 4, abbreviated as rhG-CSF group) in which the beagles were subcutaneously injected with 200 µg/kg of rhG-CSF early at half an hour and 24 hours post-irradiation respectively. The results showed that 2.3 Gy 90% neutron irradiation induced a severe acute radiation sickness of bone marrow type. The administration of rhG-CSF increased the survival rate from 60% in supportive care group to 100%. Twice injection of rhG-CSF in the first 24 hours reduced duration of neutropenia, enhanced neutrophil nadir and promoted neutrophil recovery when compared with control cohort administered clinical support. The number of colony-forming cells (CFU-GM, CFU-E, and BFU-E) in peripheral blood of rhG-CSF treated canines increased 2-to 5-fold relative to those of the supportive care group on day 3. All canines treated with rhG-CSF achieved hematopoietic reconstruction as evidenced by the pathological section of sternum while severe shortage of hemopoietic cells remained in the cohorts given supportive care alone. It is concluded that the combination of supportive care and high-dose rhG-CSF can accelerate hematopoietic recovery and enhance survival of dogs exposed to 2.3 Gy mixed neutron and gamma ray.

Identification of differentially expressed genes of acute hypoxia-treated HepG2 cells and hypoxia-acclimatized HepG2 cells / 生理学报

To provide necessary information for further understanding of molecular mechanism of hypoxia acclimatization, the differentially expressed genes of HepG2 cells exposed to normoxia, acute hypoxia-treated cells which were exposed to 1% oxygen for 48 h, and hypoxia-acclimatized HepG2 cells which were cultured for 6 circles of alternate low oxygen (1% oxygen for 24 h) and normal oxygen (21% oxygen for 24 h), were identified respectively by combining the suppression subtractive hybridization (SSH) and cDNA microarray. Thirty-seven genes were expressed differentially in cells exposed to 1% oxygen for 48 h compared with those in cells exposed to normoxia. The expression of all these 37 genes was down-regulated, including the genes participating in cell cycle, cell response to stimulus, and cell signal transduction, and cell cytoskeleton formation, the genes associated with transcription and cell metabolism, 4 expressed sequence tags (ESTs), and 12 genes of which the functions are not known. There is a novel gene sequence, which has not been found in existing databases. There were only 6 genes differentially expressed in the hypoxia-acclimatized cells compared with cells exposed to normoxia, including two mitochondrion genes, metalloprotease-1 gene, ferritin gene, thymosin beta-4 and TPT1 genes. The expressions of mitochondrion ND4, ferritin, thymosin beta-4 and TPT1 were up-regulated, while the expressions of mitochondrion ND1 gene and metalloproease-1 gene were down-regulated. Cell tolerance to hypoxia increased after the cells were hypoxia-acclimatized. The different gene expression patterns of the acute hypoxia-treated cells and the hypoxia-acclimatized cells may be related to the increased tolerance of the cells to hypoxia.