A highly selective fluorescent nanoprobe based on AIE and ESIPT for imaging hydrogen sulfide in live cells and zebrafish

2017 ◽  
Vol 1 (5) ◽  
pp. 838-845 ◽  
Author(s):  
Peisheng Zhang ◽  
Xuezheng Nie ◽  
Meng Gao ◽  
Fang Zeng ◽  
Anjun Qin ◽  
...  
Keyword(s):  
Hydrogen Sulfide ◽  
Live Cells ◽  
Specific Detection ◽  
Fluorescent Nanoprobe

An AIE/ESIPT-based nanoprobe has been developed for the specific detection and imaging of H2Sin vitroandin vivo.

Multi-mode light microscopy of microtubule assembly dynamics and chromosome movement in vivo and In vitro

1996 ◽  
Vol 54 ◽  
pp. 730-731
Author(s):  
E. D. Salmon ◽  
J. C. Waters ◽  
C. Waterman-Storer
Keyword(s):  
Imaging System ◽  
Ccd Camera ◽  
Transmitted Light ◽  
Microtubule Assembly ◽  
Live Cells ◽  
Optical Efficiency ◽  
Multiple Band ◽  
Multi Mode

We have developed a multi-mode digital imaging system which acquires images with a cooled CCD camera (Figure 1). A multiple band pass dichromatic mirror and robotically controlled filter wheels provide wavelength selection for epi-fluorescence. Shutters select illumination either by epi-fluorescence or by transmitted light for phase contrast or DIC. Many of our experiments involve investigations of spindle assembly dynamics and chromosome movements in live cells or unfixed reconstituted preparations in vitro in which photodamage and phototoxicity are major concerns. As a consequence, a major factor in the design was optical efficiency: achieving the highest image quality with the least number of illumination photons. This principle applies to both epi-fluorescence and transmitted light imaging modes. In living cells and extracts, microtubules are visualized using X-rhodamine labeled tubulin. Photoactivation of C2CF-fluorescein labeled tubulin is used to locally mark microtubules in studies of microtubule dynamics and translocation. Chromosomes are labeled with DAPI or Hoechst DNA intercalating dyes.

Endogenous hydrogen sulfide sulfhydrates IKKβ at cysteine 179 to control pulmonary artery endothelial cell inflammation

2019 ◽  
Vol 133 (20) ◽  
pp. 2045-2059 ◽  
Author(s):  
Da Zhang ◽  
Xiuli Wang ◽  
Siyao Chen ◽  
Selena Chen ◽  
Wen Yu ◽  
...  
Keyword(s):  
Hydrogen Sulfide ◽  
Endothelial Cell ◽  
Pulmonary Artery ◽  
Cell Model ◽  
Site Directed Mutagenesis ◽  
Critical Event ◽  
Hypertensive Rats ◽  
Pulmonary Artery Endothelial Cell

Abstract Background: Pulmonary artery endothelial cell (PAEC) inflammation is a critical event in the development of pulmonary arterial hypertension (PAH). However, the pathogenesis of PAEC inflammation remains unclear. Methods: Purified recombinant human inhibitor of κB kinase subunit β (IKKβ) protein, human PAECs and monocrotaline-induced pulmonary hypertensive rats were employed in the study. Site-directed mutagenesis, gene knockdown or overexpression were conducted to manipulate the expression or activity of a target protein. Results: We showed that hydrogen sulfide (H2S) inhibited IKKβ activation in the cell model of human PAEC inflammation induced by monocrotaline pyrrole-stimulation or knockdown of cystathionine γ-lyase (CSE), an H2S generating enzyme. Mechanistically, H2S was proved to inhibit IKKβ activity directly via sulfhydrating IKKβ at cysteinyl residue 179 (C179) in purified recombinant IKKβ protein in vitro, whereas thiol reductant dithiothreitol (DTT) reversed H2S-induced IKKβ inactivation. Furthermore, to demonstrate the significance of IKKβ sulfhydration by H2S in the development of PAEC inflammation, we mutated C179 to serine (C179S) in IKKβ. In purified IKKβ protein, C179S mutation of IKKβ abolished H2S-induced IKKβ sulfhydration and the subsequent IKKβ inactivation. In human PAECs, C179S mutation of IKKβ blocked H2S-inhibited IKKβ activation and PAEC inflammatory response. In pulmonary hypertensive rats, C179S mutation of IKKβ abolished the inhibitory effect of H2S on IKKβ activation and pulmonary vascular inflammation and remodeling. Conclusion: Collectively, our in vivo and in vitro findings demonstrated, for the first time, that endogenous H2S directly inactivated IKKβ via sulfhydrating IKKβ at Cys179 to inhibit nuclear factor-κB (NF-κB) pathway activation and thereby control PAEC inflammation in PAH.

scholarly journals H2S in acute lung injury: a therapeutic dead end(?)

2020 ◽  
Vol 8 (S1) ◽  
Author(s):  
Tamara Merz ◽  
Nicole Denoix ◽  
Martin Wepler ◽  
Holger Gäßler ◽  
David A. C. Messerer ◽  
...  
Keyword(s):  
Hydrogen Sulfide ◽  
Acute Lung Injury ◽  
Lung Injury ◽  
Circulatory Shock ◽  
Therapeutic Window ◽  
Pharmacokinetics And Pharmacodynamics ◽  
Clinical Reality ◽  
Dead End

AbstractThis review addresses the plausibility of hydrogen sulfide (H2S) therapy for acute lung injury (ALI) and circulatory shock, by contrasting the promising preclinical results to the present clinical reality. The review discusses how the narrow therapeutic window and width, and potentially toxic effects, the route, dosing, and timing of administration all have to be balanced out very carefully. The development of standardized methods to determine in vitro and in vivo H2S concentrations, and the pharmacokinetics and pharmacodynamics of H2S-releasing compounds is a necessity to facilitate the safety of H2S-based therapies. We suggest the potential of exploiting already clinically approved compounds, which are known or unknown H2S donors, as a surrogate strategy.

scholarly journals Insights in Behavior of Variably Formulated Alginate-Based Microcapsules for Cell Transplantation

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Pia Montanucci ◽  
Silvia Terenzi ◽  
Claudio Santi ◽  
Ilaria Pennoni ◽  
Vittorio Bini ◽  
...  
Keyword(s):  
Divalent Cations ◽  
Chemical Properties ◽  
Live Cells ◽  
High Performing ◽  
Physical Chemical ◽  
Degenerative Disorders ◽  
Selection Of ◽  
Better Than

Alginate-based microencapsulation of live cells may offer the opportunity to treat chronic and degenerative disorders. So far, a thorough assessment of physical-chemical behavior of alginate-based microbeads remains cloudy. A disputed issue is which divalent cation to choose for a high performing alginate gelling process. Having selected, in our system, high mannuronic (M) enriched alginates, we studied different gelling cations and their combinations to determine their eventual influence on physical-chemical properties of the final microcapsules preparation,in vitroandin vivo. We have shown that used of ultrapure alginate allows for high biocompatibility of the formed microcapsules, regardless of gelation agents, while use of different gelling cations is associated with corresponding variable effects on the capsules’ basic architecture, as originally reported in this work. However, only the final application which the capsules are destined to will ultimately guide the selection of the ideal, specific gelling divalent cations, since in principle there are no capsules that are better than others.

scholarly journals Hydrogen Sulfide–Releasing Aspirin Derivative ACS14 Exerts Strong Antithrombotic Effects In Vitro and In Vivo

2012 ◽  
Vol 32 (12) ◽  
pp. 2884-2891 ◽  
Author(s):  
Joachim Pircher ◽  
Franziska Fochler ◽  
Thomas Czermak ◽  
Hanna Mannell ◽  
Bjoern F. Kraemer ◽  
...  
Keyword(s):  
Hydrogen Sulfide ◽  
Antithrombotic Effects

scholarly journals SIMILARITY OF THE KINETICS OF INVERTASE ACTION IN VIVO AND IN VITRO. II

1932 ◽  
Vol 16 (2) ◽  
pp. 233-242 ◽  
Author(s):  
B. G. Wilkes ◽  
Elizabeth T. Palmer
Keyword(s):  
Physiological Activity ◽  
Outer Region ◽  
Living Cells ◽  
Yeast Cells ◽  
Live Cells ◽  
Intracellular Enzyme ◽  
Relationship Of ◽  
Kinetics Of

1. The pH-activity relationship of invertase has been studied in vivo and in vitro under identical external environmental conditions. 2. The effect of changing (H+) upon the sucroclastic activity of living cells of S. cerevisiae and of invertase solutions obtained therefrom has been found, within experimental error, to be identical. 3. The region of living yeast cells in which invertase exerts its physiological activity changes its pH freely and to the same extent as that of the suspending medium. It is suggested that this may indicate that this intracellular enzyme may perform its work somewhere in the outer region of the cell. 4. In using live cells containing maltase, no evidence of increased sucroclastic activity around pH 6.9, due to the action of Weidenhagen's α-glucosidase (maltase), was found.

scholarly journals Overexpressed Pituitary Tumor-Transforming Gene Causes Aneuploidy in Live Human Cells

Endocrinology ◽  
2003 ◽  
Vol 144 (11) ◽  
pp. 4991-4998 ◽  
Author(s):  
Run Yu ◽  
Wenge Lu ◽  
Jiandong Chen ◽  
Chris J. McCabe ◽  
Shlomo Melmed
Keyword(s):  
Cancer Cells ◽  
Chromosome Segregation ◽  
Pituitary Tumor ◽  
Fluorescent Protein ◽  
Human Cancer ◽  
Live Cells ◽  
Pituitary Tumor Transforming Gene ◽  
Transforming Gene

Abstract The mammalian securin, pituitary tumor-transforming gene (PTTG), is overexpressed in several tumors and transforms cells in vitro and in vivo. To test the hypothesis that PTTG overexpression causes aneuploidy, enhanced green fluorescent protein (EGFP)-tagged PTTG (PTTG-EGFP) was expressed in human H1299 cancer cells (with undetectable endogenous PTTG expression) and mitosis of individual live cells observed. Untransfected cells and cells expressing EGFP alone exhibited appropriate mitosis. PTTG-EGFP markedly prolonged prophase and metaphase, indicating that PTTG blocks progression of mitosis to anaphase. In cells that underwent apparently normal mitosis (35 of 65 cells), PTTG-EGFP was degraded about 1 min before anaphase onset. Cells that failed to degrade PTTG-EGFP exhibited asymmetrical cytokinesis without chromosome segregation (18 of 65 cells) or chromosome decondensation without cytokinesis (9 of 65 cells), resulting in appearance of a macronucleus. Fifty-one of 55 cells expressing a nondegradable mutant PTTG exhibited asymmetrical cytokinesis without chromosome segregation, and some (4 of 55) decondensed chromosomes, both resulting in macronuclear formation. During this abnormal cytokinesis, all chromosomes and spindles and both centrosomes moved to one daughter cell, suggesting potential chaos in the subsequent mitosis. In conclusion, failure of PTTG degradation or enhanced PTTG accumulation, as a consequence of overexpression, inhibits mitosis progression and chromosome segregation but does not directly affect cytokinesis, resulting in aneuploidy. These results demonstrate that PTTG induces aneuploidy in single, live, human cancer cells.

scholarly journals Interaction between Acetylated MyoD and the Bromodomain of CBP and/or p300

2001 ◽  
Vol 21 (16) ◽  
pp. 5312-5320 ◽  
Author(s):  
Anna Polesskaya ◽  
Irina Naguibneva ◽  
Arnaud Duquet ◽  
Eyal Bengal ◽  
Philippe Robin ◽  
...  
Keyword(s):  
Transcriptional Activation ◽  
Protein Function ◽  
Live Cells ◽  
Regulation Of Transcription ◽  
Muscle Creatine Kinase ◽  
Nonhistone Protein ◽  
Myogenic Factor ◽  
First Time

ABSTRACT Acetylation is emerging as a posttranslational modification of nuclear proteins that is essential to the regulation of transcription and that modifies transcription factor affinity for binding sites on DNA, stability, and/or nuclear localization. Here, we present both in vitro and in vivo evidence that acetylation increases the affinity of myogenic factor MyoD for acetyltransferases CBP and p300. In myogenic cells, the fraction of endogenous MyoD that is acetylated was found associated with CBP or p300. In vitro, the interaction between MyoD and CBP was more resistant to high salt concentrations and was detected with lower doses of MyoD when MyoD was acetylated. Interestingly, an analysis of CBP mutants revealed that the interaction with acetylated MyoD involves the bromodomain of CBP. In live cells, MyoD mutants that cannot be acetylated did not associate with CBP or p300 and were strongly impaired in their ability to cooperate with CBP for transcriptional activation of a muscle creatine kinase-luciferase construct. Taken together, our data suggest a new mechanism for activation of protein function by acetylation and demonstrate for the first time an acetylation-dependent interaction between the bromodomain of CBP and a nonhistone protein.

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