Cytoplasmic signaling involved in sonoporation-induced apoptosis andmitosis repression of myeloid leukemia cells

Sonoporation is known to be a transient phenomenon that may disrupt thehomeostasis of living cells. In this work, we showed that sonoporation may beartime-lapse impact on cellular viability through up-regulation of cytoplasmicsignaling proteins related to apoptosis and cell-cycle arrest. Our experimentswere done on HL-60 leukemia cells (10 6 cells/ml), and sonoporationwas induced via the use of 1% v/v microbubbles and 1-min. pulsed ultrasoundexposure (0.5MPa peak negative pressure, 1MHz center frequency, 10% duty cycle,1 kHz pulse repetition frequency). The transient nature of sonoporation in thesecells was confirmed by performing scanning electron microscopy on selected cellsamples that were fixed respectively after a few seconds into the ultrasoundexposure and one minute after the end of exposure. Cytoplasmic signaling changesof these cells were studied at four post-sonoporation time points (4h, 8h, 12h,24h) using western blot analysis. Five signaling proteins related to apoptosisand mitosis were analyzed in this work: 1) PARP (for DNA repair); 2)cleaved-PARP (fragments due to cleavage by pro-apoptotic caspase proteins); 3)Bcl-2 (inhibitor for mitochrondrial release of pro-apoptotic molecules); 4) Bax(complement of Bcl-2); 5) Cdc-2 (regulator for cell mitosis). Three key resultswere found from the cytoplasmic signaling analysis. First, PARP levels werereduced over the monitoring period whilst cleaved-PARP had increased inexpression, and in turn they indicate that the cells' anti-apoptotic responseswere dampened following sonoporation and pro-apoptotic caspase proteins werelikely activated. Second, drop in Bcl-2 and rise in Bax were observed, and thesesuggest that the mitochondrion was involved in apoptotic signal transductioninside sonoporated cells. Third, Cdc-2 was seen to decrease, implying thatmitosis was repressed in sonoporated cells. © 2010 IEEE.published_or_final_versionThe 2010 IEEE International Ultrasonics Symposium, San Diego, CA., 11-14 October 2010. In Proceedings of IEEE IUS, 2010, p. 1771-177

Cordyceps cicadae induces G2/M cell cycle arrest in MHCC97H human hepatocellular carcinoma cells: a proteomic study

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Protection of lethal toxicity of endotoxin by Salvia miltiorrhiza BUNGE is via reduction in tumor necrosis factor alpha release and liver injury

Lipopolysaccharide (LPS) has been implicated as one of the major cause of Gram-negative bacteria-induced sepsis that are life-threatening syndromes occurring in intensive care unit patients. Many natural products derived from medicinal plants may contain therapeutic values on protecting endotoxemia-induced sepsis by virtue their ability to modulate multiple pro-inflammatory cytokines. In the present study, we show that Salvia miltiorrhiza (SM) BUNGE or Danshen, used in treatment of various systemic and surgical infections in the hospitals of China, was able to block the lethal toxicity of LPS in mice via suppression of TNF-α release and protection on liver injury. The ability of SM to suppress LPS-induced TNF-α release is further confirmed by in vitro experiments conducted on human peripheral blood leukocytes (PBL) and the RAW 264.7 macrophage cell line. Immunophenotyping by flow cytometry shows improved T-helper cell (CD4) and T-suppressor cells (CD8) ratio in SM-treated PBL and splenocytes of LPS-challenged mice. The drop in plasma glutamate-pyruvate transaminase (GPT) induced by LPS provides evidence that SM can protect hepatic damage. The present study explains some known biological activities of SM, and supports the clinical application of SM in the prevention of inflammatory diseases induced by Gram-negative bacteria. © 2005 Elsevier B.V. All rights reserved.postprin

Antibiotics Increase Gut Metabolism and Antioxidant Proteins and Decrease Acute Phase Response and Necrotizing Enterocolitis in Preterm Neonates

Background: The appropriate use of antibiotics for preterm infants, which are highly susceptible to develop necrotizing enterocolitis (NEC), is not clear. While antibiotic therapy is commonly used in neonates with NEC symptoms and sepsis, it remains unknown how antibiotics may affect the intestine and NEC sensitivity. We hypothesized that broad-spectrum antibiotics, given immediately after preterm birth, would reduce NEC sensitivity and support intestinal protective mechanisms. Methodology/Principal Findings: Preterm pigs were treated with antibiotics for 5 d (oral and systemic doses of gentamycin, ampicillin and metrodinazole; AB group) and compared with untreated pigs. Only the untreated pigs showed evidence of NEC lesions and reduced digestive function, as indicated by lowered villus height and activity of brush border enzymes. In addition, 53 intestinal and 22 plasma proteins differed in expression between AB and untreated pigs. AB treatment increased the abundance of intestinal proteins related to carbohydrate and protein metabolism, actin filaments, iron homeostasis and antioxidants. Further, heat shock proteins and the complement system were affected suggesting that all these proteins were involved in the colonization-dependent early onset of NEC. In plasma, acute phase proteins (haptoglobin, complement proteins) decreased, while albumin, cleaved C3, ficolin and transferrin increased. Conclusions/Significance: Depressed bacterial colonization following AB treatment increases mucosal integrity and reduces bacteria-associated inflammatory responses in preterm neonates. The plasma proteins C3, ficolin, and transferrin are potential biomarkers of the colonization-dependent NEC progression in preterm neonates. © 2012 Jiang et al.published_or_final_versio

2017 HRS/EHRA/ECAS/APHRS/SOLAECE expert consensus statement on catheter and surgical ablation of atrial fibrillation: executive summary.

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Activation of caspase is independent to cyclin E expression in camptothecin-induced apoptosis in HL-60 cells

Introduction: In response to the DNA topoisomerase I inhibitor camptothecin(CAM), leukemia HL-60 cells undergo characteristic morphological changes,caspase activation, and DNA fragmentation typical of apoptosis. The sequence ofapoptotic phenomena in an individual CAM-treated HL-60 cell is said to dependon the stage of proliferation of that cells when it encounters the CAM. This studydescribes further investigation on the dose and time effect of CAM on the apop-totic phenomena using the broad-spectrum caspase inhibitor Z-VAD-FMK. Therelationship between caspase and cyclin E in CAM-induced apoptosis was alsoinvestigated. Methods: The dose-response (10 nM, 50 nM and 1000 nM) of CAMon cell cycle progression and cell death on HL-60 cells in the presence andabsence of the caspase inhibitor was monitored by flow cytometry during 24-hcultures. Cell death was monitored by changes in cell light scatter and binding ofannexin V-fluorescein isothiocyanate to PS. Results: High doses (50, 1000 nM)of CAM executed all S-phase cells to undergo apoptosis after 4h whereas low (10nM) dose perturbed the whole cell cycle progression resulted with late apoptoticcell death after 12h. Caspase inhibition prevented PS exposure mainly from S-phase cells but had no effect on the cell death pathway of the non-S-phase cells.Cyclin E expression appeared earlier than activation of PS exposure and contin-ued to rise with treatment time; independent to concentrations of CAM and thepresence of general caspase inhibitor. Conclusion: The apoptotic phenomena inan individual HL-60 cell depend on the stage of proliferation of that cells, doseand time of CAM added. Our data show that caspases are only required for PSexposure-related cell death. The overexpression of cyclin E by CAM aims to sen-sitize the HL-60 cells to undergo apoptosis.link_to_subscribed_fulltex

Polysaccharopeptide enhances the anticancer activity of doxorubicin and etoposide on human breast cancer cells ZR-75-30

In search of natural bioactive microbial compounds with adjuvant properties, we have previously showed that the polysaccharopeptide (PSP), isolated from Chinese medicinal mushroom Coriolus versicolor, was able to enhance the cytotoxicity of certain S-phase targeted-drugs on human leukemic HL-60 cells via some cell-cycle and apoptotic-dependent pathways. The present study aimed to investigate whether the synergism of mechanisms of PSP with certain chemotherapeutic drugs also applies to human breast cancer. PSP treatment enhanced the cytotoxicity of doxorubicin (Doxo), etoposide (VP-16) but not cytarabine (Ara-C). Bivariate bromodeoxyuridine (BrdUrd)/DNA flow cytometry analysis estimated a longer DNA synthesis time (Ts) for the PSP treated cancerous cells suggesting that PSP enhanced the apoptotic effect of Doxo and VP-16 via creating an S-phase trap in the human breast cancer cell line ZR-75-30. The participation of PSP in the apoptotic machinery of the chemotherapeutic agents was further supported by a reduced ratio of protein expression of Bcl-xL/Bax of the cancer cells. This study provides further insight into the synergistic mechanisms of PSP and supports the hypothesis that the anti-cancer potentials of PSP is not limited to leukemia but may also be used as an adjuvant therapy for breast cancers.link_to_OA_fulltex