Volatile organic compounds from fungi isolated after hurricane katrina induce developmental defects and apoptosis in a Drosophila melanogaster model

In previous work, our laboratory developed a Drosophila model for studying the adverse effects of fungal volatile organic compounds (VOCs) emitted by growing cultures of molds. In this report, we have extended these studies and compared the toxic effects of fungal VOCs emitted from living cultures of four molds isolated after Hurricane Katrina from a flooded home in New Orleans. Strains of Aspergillus, Mucor, Penicillium, and Trichoderma were grown with wild‐type larvae and the toxic effects of volatile products on the developmental stages of Drosophila larvae were evaluated. Furthermore, heterozygous mutants of Drosophila carrying the apoptotic genes, reaper and dronc, were used to assess the role of apoptosis in fungal VOCs mediated toxicity. Third‐instar larvae of Drosophila carrying these apoptotic genes were exposed to fungal VOCs emitted from growing mold cultures for 10 days. The larval strains carrying apoptopic genes survived longer than the control wild type larvae; moreover, of those that survived, heterozygous reaper and dronc strains progressed to pupae and adult phases more rapidly, suggesting that fungal VOCs may induce apoptotic changes in flies. These data lend support to the use of Drosophila as an inexpensive and genetically versatile toxicological model to investigate the mechanistic basis for some of the human illnesses/symptoms associated with exposure to mold‐contaminated indoor air, especially after hurricanes. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 614–620, 2015.     

肝癌细胞凋亡端粒酶活性和bcl-2基因表达

目的　探讨经肝动脉化疗栓塞 (TACE)后bcl 2蛋白在肝癌细胞凋亡中的作用。方法　应用免疫组织化学法和原位末端标记法 (ISEL)检测 6 5例原发性肝癌患者分组治疗前后bcl 2蛋白表达和肝癌细胞凋亡。结果　肝癌 (HCC)患者不同治疗方法肝细胞凋亡阳性率和bcl 2阳性率均低于对照组 (P <0 0 5～0 0 1) ,端粒酶阳性率高于对照组 (P <0 0 5 ) ;手术 化疗组的有效率和生存率均高于其他两组 ;中晚期肝癌生存率低于早期肝癌 (P <0 0 5～ 0 0 1) ;直径≥ 10cm中晚期肝癌生存率低于直径 <10cm中晚期肝癌 (P <0 0 5～ 0 0 1)。结论　细胞凋亡、端粒酶活性和bcl 2基因表达在肝癌发展过程中有重要作用。     

Investigating the effects of functionalized carbon nanotubes on reproduction and development in Drosophila melanogaster and CD-1 mice

Despite numerous applications for functionalized carbon nanotubes (fCNTs) in consumer products, such as electronics, and food packaging, as well as their development as drug delivery vehicles, the consequence of their uptake by living systems has been understudied. In particular, the impact of fCNTs on early development of different species is largely unknown. Here we investigated the effect of ingested hydroxyl-fCNTs on reproduction and development in two model organisms: Drosophila and CD-1 mice. While fCNTs had no measurable impact on Drosophila, a single oral dose of fCNTs (10 mg/kg) administered to pregnant CD-1 dams during organogenesis significantly increased the number of resorptions and resulted in fetal morphological and skeletal abnormalities. The observed difference between the responses of these two models likely reflects their physiology and/or differences in administration. This research underscores the need to examine the effects of fCNTs on reproductive health and development before the opportunities for maternal exposure by fCNTs increase further.     

细胞凋亡过程中核糖体蛋白质S3a水平变化的研究（三）：——检测细胞凋亡过程中RPS3a水平的变化

目的：检测细胞凋亡过程中RPS3a水平的变化，探讨RPS3a在细胞凋亡中的作用。方法：用放射菌素D（Act D）诱导HL－60细胞发生凋亡。应用WesternBlot法检测细胞凋亡过程中RPS3a水平的变化，结果：HL－60细胞在诱发凋亡1小时后，RPS3a的水平与对照组比较显著升高，之后迅速降低，在诱导2h时其水平已低于正常对照组的水平，并随时间推移逐渐降低，在细胞凋亡的晚期，即诱导6h时，RPS3a已降至不可检测的水平，结论：RPRS3a水平出现的一过性增高随后迅速降低，这可能是发挥其核糖体外的功能，作为信号诱导细胞凋亡；在细胞凋亡的早期RPRS3a的不可逆性降致使核糖体的完整性丧失，从而抑制蛋白质的合成，最终导致细胞凋亡。     

Adverse effect of tannery waste leachates in transgenic Drosophila melanogaster: role of ROS in modulation of Hsp70, oxidative stress and apoptosis

Leachate is a complex chemical mixture of chemicals produced as a result of leaching of solid wastes. The potential toxicity of leachates is a major environmental health concern. The present study evaluated the role of ROS in tannery leachates induced Hsp70 expression, antioxidant enzymes and apoptosis in Drosophila. Different concentrations (0.05-2.0%) of leachates prepared from tannery waste at different pH (7.00, 4.93 and 2.88) were mixed with Drosophila food and fed to the larvae for 2-48 h to examine the different stress and apoptotic markers. A concentration- and time-dependent significant increase in Hsp70 expression, ROS generation, antioxidant enzymes activities and MDA content were observed in the exposed larvae. Activities of antioxidant enzymes were delayed compared with Hsp70 expression and MDA level in the exposed organisms. Apoptotic cell death was observed in the exposed larvae at higher concentrations concurrent with a significant regression in Hsp70 along with a higher level of ROS generation. A positive correlation drawn between ROS generation and apoptotic markers and a negative correlation between apoptotic markers and Hsp70 expression at these concentrations indicated the important role of ROS in the induction of cellular damage in the exposed organisms. There was a significant generation of ROS in the larvae exposed to 0.5% of leachates which did not interfere with the protection of their cells by Hsp70 and antioxidant enzymes. However, generation of significantly higher levels of ROS in the larvae exposed to 1.0% and 2.0% leachates may decrease Hsp70 expression thus leading to mitochondria-mediated caspase-dependent apoptotic cell death.     

X连锁凋亡抑制蛋白通路在白花蛇舌草的有效成分2-羟基-3-甲基蒽醌诱导的人白血病细胞HL-60凋亡中的作用

目的探讨白花蛇舌草的有效成分2-羟基-3-甲基蒽醌诱导人白血病细胞HL-60细胞凋亡的机制。方法以HL-60细胞作为体外细胞模型,当作用时间分别为0、24、48及72 h时,用Hoechst 33258荧光染色技术、Annexin V FITC/PI双染流式细胞仪检测HL-60细胞凋亡率;Western blot检测Survivin、Smac、c IAP1/2、XIAP等蛋白的表达。结果作用24 h时,即可引起HL-60细胞发生凋亡,HL-60细胞凋亡百分率随作用时间的延长而增加。Hoechst 33258荧光染色及流式细胞仪两种方法所得结果一致。随着作用时间的延长,XIAP和c IAP1/2表达逐渐下降,而Smac表达逐渐增加。结论白花蛇舌草的有效成分2-羟基-3-甲基蒽醌能够诱导HL-60细胞凋亡,XIAP信号通路在此过程中起到重要作用。     

Effect of rhodoxanthin from Potamogeton crispus L. on cell apoptosis in Hela cells

Carotenoid, a natural functional pigment, is known to have anti-carcinogenic activity. To verify the anti-cancer effects of rhodoxanthin which is a kind of carotenoids, we investigated the effects of rhodoxanthin from Potamogeton crispus L. on the proliferation rate, cell cycle distribution, apoptosis and the change in mitochondrial membrane potential in Hela cell line. The effects of rhodoxanthin were also tested on the concentration of Ca²⁺ in cells. Rhodoxanthin inhibited cell proliferation in Hela cells in a dose and time-dependent manner. Rhodoxanthin induced an accumulation of cells in the S phase of the cell cycle, reduced the mitochondria transmembrane potential and increased the concentration of intracellular Ca²⁺. In summary, our results suggested that rhodoxanthin-induced apoptosis in Hela cells occured via these pathways.     

Disruption of mitochondrial complexes,cytotoxicity, and apoptosis results from Mancozeb exposure in transformed human colon cells

Ethylene bisdithiocarbamate pesticides, including Mancozeb (MZ), are used as fungicides. Effects of MZ on apoptosis induction and mitochondrial activity of HT-29 colon cells were investigated. MZ exposed cells exhibited blebbing and cellular membrane disruption in scanning electron micrographs. Positive fluorescent staining with Annexin V at doses of 60–140 μM supports apoptosis as the mechanism of cell death. Activity of all electron transport chain complexes were evaluated. Mitochondrial Complex I activity was decreased in 100 μM treated cells. Mitochondrial Complex III activity was decreased in 60 and 100 μM MZ treated cells. Mitochondrial Complex II and Complex IV activities were decreased in cells treated with 60, 100, and 140 μM. Cells treated with 60 μM exhibited a decrease in Complex V enzyme activity. It is concluded that MZ exposure inhibits all mitochondrial complexes of HT-29 cells and that positive fluorescent microscopy and blebbing support previous studies of cell death via apoptosis.     

Induction of apoptosis by isoegomaketone from Perilla frutescens L. in B16 melanoma cells is mediated through ROS generation and mitochondrial-dependent, -independent pathway

We have demonstrated for the first time the mechanism underlying ROS-mediated mitochondria-dependent apoptotic cell death triggered by isoegomaketone (IK) treatment in melanoma cells. We showed that IK induced apoptotic cell death and tumor growth inhibition using tissue culture and in vivo models of B16 melanoma. Furthermore, we observed that IK effectively induced apoptotic cell death, including sub-G1 contents up-regulation, nuclei condensation, DNA fragmentation, and caspase activation in B16 melanoma cells. Pretreatment with caspase inhibitor increased the survival rate of IK-treated B16 cells, implying that caspases play a role in IK-induced apoptosis. Furthermore, IK treatment generated ROS in melanoma cells. We also determined whether or not IK-induced cell death is due to ROS production in B16 cells. N-acetyl cysteine (NAC) inhibitedIK-induced Bcl-2 family-mediated apoptosis. This result indicates that IK-induced apoptosis involves ROS generation as well as up-regulation of Bax and Bcl-2 expression, leading to release of cytochrome c and AIF. Our data suggest that IK inhibits growth and induces apoptosis in melanoma cells via activation of ROS-mediated caspase-dependent and -independent pathways.     

啤酒花中蛇麻酮体外诱导人胃癌SGC-7901细胞凋亡作用研究

目的探讨啤酒花(Humulus LupulusL.)中成分蛇麻酮(Lupulone,LP)体外对人胃癌细胞SGC-7901生长抑制及诱导凋亡作用的研究。方法体外培养人胃癌细胞株SGC-7901,MTT法检测不同浓度蛇麻酮对SGC-7901细胞体外生长的影响;流式细胞仪分析蛇麻酮对SGC-7901细胞的凋亡率的影响。结果蛇麻酮对SGC-7901的生长具有较强的抑制作用,IC50为0.73μg/mL;0、0.2、0.8、3.2μg/mL剂量的蛇麻酮作用SGC-7901细胞48h细胞凋亡率分别为0.1%、7.1%、18.0%、49.3%。结论蛇麻酮对SGC-7901具有较强的抗肿瘤活性,其机制可能与其可诱导肿瘤细胞凋亡有关。     

槐米中槲皮素提纯、鉴定以及诱导人乳腺癌MCF-7细胞凋亡作用

目的:研究从槐米中槲皮素(Quercetin,Que)提取、鉴定和对人乳腺癌MCF-7细胞生长的抑制以及诱导凋亡作用.方法:采用碱溶解酸沉淀法提纯槐米中槲皮素,并进行红外光谱分析;采用体外培养人乳腺癌MCF-7细胞,用不同浓度槲皮素处理;采用四甲基偶氮唑蓝(MTT)比色法测定细胞生长抑制率;采用细胞凋亡DNA Lad　der和FITC-Annexin V/PI荧光标记流式细胞仪检测,槲皮素作用后MCF-7细胞凋亡情况.结果:不同浓度槲皮素对人乳腺癌MCF 7细胞有生长抑制作用,并呈浓度和时间依赖性(P＜0.05);10.0 mmol/L槲皮素作用MCF-7细胞2d,DNA电泳出现特征性的凋亡条带;10.0 mmol/L槲皮素处理MCF-7细胞1d、2d和3d,细胞凋亡率分别为(9.2±1.5)％、(30.0±11.8)％和(60.8±10.6)％.结论:用碱溶解酸沉淀法可从槐米中提纯槲皮素,提取的槲皮素对人乳腺癌MCF-7细胞有生长抑制和诱导凋亡作用.     

Induction of apoptosis in HT-29 colon cancer cells by crude saponin from Platycodi Radix

This study examined the apoptotic effects of crude saponins acquired from the roots of Platycodon grandiflorum (SPR) in HT-29 human colon cancer cells.SPR decreased HT-29 cell proliferation in dose- and time-dependent manners by inducing apoptosis via DNA fragmentation and poly (ADP-ribose) polymerase (PARP) cleavage. The apoptosis induced by SPR was associated with the activation of initiator caspases-8 and -9, as well as the effector caspase-3. SPR stimulated Bid cleavage, indicating that the apoptotic action of caspase-8-mediated Bid cleavage leads to the activation of caspase-9. SPR increased the expression of the pro-apoptotic protein, Bax, and decreased the expression of the anti-apoptotic protein, Bcl-2. SPR also increased the expression of the caspase-independent mitochondrial apoptosis factor, AIF, in HT-29 cells. These results indicate that SPR inhibits HT-29 cell proliferation by inducing apoptosis, which may be mediated via both caspase-dependent and -independent pathways.     

Mechanisms of thiosulfinates from Allium tuberosum L.-induced apoptosis in HT-29 human colon cancer cells

This study was performed to elucidate the apoptotic pathways by thiosulfinates, major biologically active components of Allium tuberosum L., in HT-29 human colon cancer cells. Thiosulfinates significantly induced cell death in dose- and time-dependent manners in HT-29 cells, which is associated with apoptosis. Thiosulfinates activated the initiator caspase-8, and -9, and the effector caspase-3. In the present study, thiosulfinates were found to stimulate Bid cleavage, indicating that the apoptotic action of caspase-8-mediated Bid cleavage leads to the activation of caspase-9. Thiosulfinates down-regulated the expression of the anti-apoptotic protein Bcl-2, and up-regulated the expression of the pro-apoptotic protein Bax. We also found that thiosulfinates increased the expression of AIF, a caspase-independent mitochondrial apoptosis factor, and induced DNA fragmentation and chromatin condensation in HT-29 cells. These results indicate that thiosulfinates from A. tuberosum L. inhibited cell proliferation and activated both the caspase-dependent and caspase-independent apoptotic pathways in HT-29 cells.     

Mechanism of apoptosis induced by a polysaccharide, from the loach Misgurnus anguillicaudatus (MAP) in human hepatocellular carcinoma cells

The biological activities of the polysaccharide have attracted more and more attention in the biochemical and medical areas due to their anti-cancer effects. To estimate the anti-tumor mechanism of MAP, a novel polysaccharide from the loach, Misgurnus anguillicaudatus, the apoptosis effects of the polysaccharide on the human hepatocellular carcinoma cells (SMMC-7721 cells) were studied. The present studies showed that MAP could induce cell apoptosis which was closely accompanied with an increase of intracellular-free calcium concentration ([Ca2+]i), the enhancement of reactive oxygen species (ROS) level, dissipation of mitochondria membrane potential (MMP), up-regulation of p53 mRNA, increase expression of Bax mRNA, and decrease expression of Bcl-2 mRNA. These results suggested that cell apoptosis induced by MAP mainly was mediated by mitochondrial pathways, not involved death receptors (DRs) pathways. The mechanism possibly is that MAP acts on mitochondria and boosts ROS, ROS mediates a release of Ca2+ from the intracellular Ca2+ pool, increasing [Ca2+]i targets the cells a start-up of the apoptosis program. However, further research on the molecular mechanisms of MAP effecting on the cells' mitochondria is necessary.     

^125IUdR对大鼠胶质瘤细胞靶点放疗后的细胞凋亡研究

目的 在建立C6／Wistar胶质瘤大鼠模型的基础上，研究^125IUdR介导俄歇电子释放对大鼠G6胶质瘤DNA靶点放疗后的肿瘤细胞凋亡。方法 建立C6／Wistar胶质瘤大鼠模型后，应用流式细胞仪检测研究C6胶质瘤细胞的增殖动力学指标。结果 实验组肿瘤细胞的S期百分比与对照组相比显著降低（P〈0．001），G2＋M期的细胞也随之减少，肿瘤细胞大量停滞在G0／G1期。实验组增殖指数明显低于对照组（P〈0．001），而凋亡指数则显著增加（P〈0．001）。结论 ^125IUdR通过电离作用导致G1期细胞增殖阻滞及DNA断裂、诱导肿瘤细胞凋亡。     

Oxidative stress induced by destruxin from Metarhizium anisopliae (Metch.) involves changes in glutathione and ascorbate metabolism and instigates ultrastructural changes in the salivary glands of Spodoptera litura (Fab.) larvae.

The cyclodepsipeptidic mycotoxin, destruxin, produced by Metarhizium anisopliae is known for its larvicidal properties. The crude destruxin-treated Spodoptera litura larvae revealed a decrease in thiol content and an increment in oxidation of glutathione to glutathione disulfide and ascorbate to dehydro ascorbate in a dose- and time-dependent manner. An increase in the levels of protein carbonyls and the free radicals, hydrogen peroxide and hydroxyl radical was also observed. These provide a clear indication of oxidative stress. Upon ingestion, destruxin causes serious damage to the epithelial cells of the midgut. We report the ultrastructural effects of crude destruxin on the salivary glands of 9-day-old S. litura larva after 24 h of treatment with the mycotoxin at a dosage of 0.147 microg/g body wt. (LD(50)). The transmission electron microscopic observations revealed characteristic changes in the salivary glands of S. litura which include detachment and damage of the microvilli, epithelial cell vacuolization, bleeding of the epithelial cells into the salivary gland lumen and disruption of the epithelial cell membrane. This investigation focuses salivary glands also as the target organ of destruxin apart from the already known midgut, Malphigian tubules and haemocytes.     

Disruption of the PI3K/AKT/mTOR signaling cascade and induction of apoptosis in HL-60 cells by an essential oil from Monarda citriodora

We have isolated an essential oil from Monarda citriodora (MC) and characterized its 22 chemical constituents with thymol (82%), carvacrol (4.82%), β-myrcene (3.45%), terpinen-4-ol (2.78%) and p-cymene (1.53%) representing the major constituents. We have reported for the first time the chemotherapeutic potential of MC in human promyelocytic leukemia HL-60 cells by means of apoptosis and disruption of the PI3K/AKT/mTOR signaling cascade. MC and its major constituent, thymol, inhibit the cell proliferation in different types of cancer cell lines like HL-60, MCF-7, PC-3, A-549 and MDAMB-231. MC was found to be more cytotoxic than thymol in HL-60 cells with an IC₅₀ value of 22 μg/ml versus 45 μg/ml for thymol. Both MC and thymol induce apoptosis in HL-60 cells, which is evident by Hoechst staining, cell cycle analysis and immuno-expression of Bcl-xL, caspase-3,-8,-9 and PARP-1 cleavage. Both induce apoptosis by extrinsic and intrinsic apoptotic pathways that were confirmed by enhanced expression of death receptors (TNF-R1, Fas), caspase-9, loss of mitochondrial membrane potential and regression of Bcl-2/Bax ratio. Interestingly, both MC and thymol inhibit the downstream and upstream signaling of PI3K/AKT/mTOR pathway. The degree of apoptosis induction and disruption of the PI3K signaling cascade by MC was significantly higher when compared to thymol.     

Effect of microcystin-LR and cyanobacterial extract from Polish reservoir of drinking water on cell cycle progression,mitotic spindle,and apoptosis in CHO-K1 cells

Microcystin-LR is a cyanobacterial toxin possessing a potent tumor-promoting activity mediated through inhibition of protein phosphatases PP1 and PP2A. Because these enzymes are involved in fundamental cell processes, we decided to examine the influence of microcystin-LR on cell cycle progression, onset of anaphase, segregation of chromosomes by the mitotic spindle, and apoptosis in Chinese hamster ovary (CHO-K1) cells. Cells were incubated with 25, 50, and 100 microM of pure microcystin-LR and a cyanobacterial extract for 14, 18, and 22 h. Giemsa staining of cells treated with these toxins revealed a dose- and time-dependent increase of mitotic indices, accumulation of abnormal G(2)/M figures with hypercondensed chromosomes, abnormal anaphases with defective chromosome separation, and polyploid cells. Because spindle checkpoint is a fundamental regulatory mechanism that assures the onset of anaphase and subsequent exit from mitosis, we examined the spindle organization in microcystin-treated cells. The majority of the mitotic cells showed monopolar and multipolar mitotic spindles (multiple asters). Microtubule bundles were present in interphase cells. Our results indicate that microcystin-LR induces apoptosis and necrosis in a dose- and time-dependent manner and that the frequency of dead cells cells is positively correlated with the frequency of polyploid cells.