Effects of the Combination of Emodin and 3'-Azido-3'-Deoxythymidine on Proliferation and Apoptosis in leukemia KG-1a cells Transfected with Egr-1 siRNA / 中国实验血液学杂志

<p><b>OBJECTIVE</b>This study was aimed to investigate the effects of emodin combined with 3'-azido-3'-deoxythymidine (AZT) on proliferation and apoptosis of leukemia cell line KG-1a cells and its mechanism.</p><p><b>METHODS</b>KG-1a cells were transfected with Egr-1 siRNA by electroporation and divided into blank control (KG-1a), nonspecific control (KG-1a/NC) and Egr-1 siRNA (KG-1a/siRNA) groups. Transfection efficiency was tested through fluorescence microscopy and flow cytometry and the transfection effect was detected by using qPCR. The cell proliferation rate was detected with MTT method. After the cells were treated with 10 µmol/L of emodin, 3200 or 1600 µmol/L of AZT and their combinations, the proliferation inhibition rates and the apoptosis rates of cells in 3 groups were detected with MTT method and FCM, respectively.</p><p><b>RESULTS</b>The transfection efficiency of Egr-1 siRNA was found to reach more than 59.21%; as compared with blank control(KG-1a) and nonspectic control(KG-1a/NC), the cell proliferation in Egr-1 siRNA group significantly reduced (P<0.01). The combination of emodin and AZT had considerable synergistic inhibitory effects on proliferation of normal KG-1a cells and nonspecific control(KG-1a NC) cells, but the synergistic effects disappeared after Egr-1 gene silencing.</p><p><b>CONCLUSION</b>The effects of the combination of emodin and AZT on proliferation and apoptosis may be related with Egr-1.</p>

Effects of AZT on leukemia cell line KG-1a proliferation and telomerase activity / 中国实验血液学杂志

This study was purposed to investigate the effect of 3'-azido-2', 3'-dideoxythymidine (AZT)on the proliferation and telomerase activity of human acute myeloid leukemia cell line KG-1a. The effect of proliferation was detected by MTT assay after the KG-1a cell were stimulated for 24, 48 and 72 h with different concentrations of AZT; telomerase activity was detected with TRAP-PCR-ELISA assay; RT-PCR was used to detect telomerase hTERT mRNA expression. The results showed that the proliferation of KG-1a cells was inhibited in a time and concentration dependent manner after exposure to AZT for 24, 48 and 72 h; the KG-1a cells decreased in S phase and increased in G(2)/M phase with the increasing of the concentration of AZT; telomerase activity and hTERT-mRNA expression in the experimental groups decreased after treated with AZT, which was positively correlated with concentration of AZT. It is concluded that AZT inhibits KG-1a cell proliferation and induces apoptosis, which maybe related with its decreasing the telomerase activity and hTERT mRNA expression.

Effects of Clostridium difficile toxin a on proliferation of K562 cells / 中国实验血液学杂志

This study was aimed to investigate the effect of clostridium difficile toxin A (Tcd A) on proliferation of K562 cells and its mechanism. The proliferative activity of K562 cells exposed to Tcd A was tested by MTT assay; cell cycle distribution and mitochondrial membrane potential were analyzed by flow cytometry; the protein expression of cytochrome C and DNA fragmentation were observed by immunohistochemistry staining and agarose gel electrophoresis respectively. The results indicated that Tcd A inhibited proliferation of K562 cells in a time-and concentration-dependent manner. Cells were arrested at G(0)/G(1) phase. Peak of apoptosis appeared. The protein expression of cytochrome C increased as compared with control group (p < 0.05). Agarose gel electrophoresis of DNA from K562 treated with Tcd A revealed a "ladder" pattern. It is concluded that clostridium difficile toxin A can inhibit proliferation and induce apoptosis of K562 cells. The mechanism may be in relation to decrease of mitochondrial membrane potential and the release of cytochrome C from mitochondria matrix.

Effect of Tangzhiping granule on blood lipids and free fatty acids in rats with insulin resistant diabetes / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To investigate the effects of Tangzhiping Granule (TZPG) on blood lipids and free fatty acids (FFA) in rats with insulin resistant diabetes (IRD).</p><p><b>METHODS</b>A blank control group consisted of randomly selected normal rats was set up. The remaining rats were established to IRD model by high-fat high-sugar diet feeding and streptozotocin injection. Then the 32 successfully modeled rats were randomized into the model group (treated by saline), the Tangmaikang group (treated with Tangmaikang Granule 1.35 g/kg), and the two TZPG groups treated with high dose (2.70 g/kg) and low dose TZPG (1.35 g/kg) respectively through intragastric infusion for 4 weeks. The body weight (BW), fasting blood glucose (FBG), insulin (INS), blood lipids including triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and FFA were detected, and the insulin sensitivity index (ISI) calculated.</p><p><b>RESULTS</b>Compared with the blank control group, BW, FBG and INS increased while ISI decreased in the model group (P < 0.05 or P < 0.01). All the above-mentioned abnormal indices were improved in the three treated groups (Tangmaikang, high and low dose TZPG group), but the improvements in the high dose TZPG group were more significant than those in the other two groups (P < 0.05 or P < 0.01). Similar outcomes were also seen in blood lipids detection, in which TG, TC, LDL-C and FFA were higher and HDL-C were lower in model rats than those in blank controls, they were improved in the three treated groups (P < 0.05), and the best improvements were seen in the high dose TZPG group (P < 0.05).</p><p><b>CONCLUSION</b>TZPG could reduce levels of BW, FBG, INS, TC, TG, LDL-C and FFA, and increase levels of ISI and HDL-C in rat model of insulin resistant type 2 diabetes, so as to improve the insulin resistance in them.</p>