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Chemical Science Feb 2018The emerging power of thiol-mediated uptake with strained disulfides called for a move from sulfur to selenium. We report that according to results with fluorescent...
The emerging power of thiol-mediated uptake with strained disulfides called for a move from sulfur to selenium. We report that according to results with fluorescent model substrates, cellular uptake with 1,2-diselenolanes exceeds uptake with 1,2-dithiolanes and epidithiodiketopiperazines with regard to efficiency as well as intracellular localization. The diselenide analog of lipoic acid performs best. This 1,2-diselenolane delivers fluorophores efficiently to the cytosol of HeLa Kyoto cells, without detectable endosomal capture as with 1,2-dithiolanes or dominant escape into the nucleus as with epidithiodiketopiperazines. Diselenolane-mediated cytosolic delivery is non-toxic (MTT assay), sensitive to temperature but insensitive to inhibitors of endocytosis (chlorpromazine, methyl-β-cyclodextrin, wortmannin, cytochalasin B) and conventional thiol-mediated uptake (Ellman's reagent), and to serum. Selenophilicity, the extreme CSeSeC dihedral angle of 0° and the high but different acidity of primary and secondary selenols might all contribute to uptake. Thiol-exchange affinity chromatography is introduced as operational mimic of thiol-mediated uptake that provides, in combination with rate enhancement of DTT oxidation, direct experimental evidence for existence and nature of the involved selenosulfides.
PubMed: 29675232
DOI: 10.1039/c7sc05151d -
Autophagy 2015Mitochondrial autophagy, also known as mitophagy, is an autophagosome-based mitochondrial degradation process that eliminates unwanted or damaged mitochondria after cell...
Mitochondrial autophagy, also known as mitophagy, is an autophagosome-based mitochondrial degradation process that eliminates unwanted or damaged mitochondria after cell stress. Most studies dealing with mitophagy rely on the analysis by fluorescence microscopy of mitochondrial-autophagosome colocalization. However, given the fundamental role of mitophagy in the physiology and pathology of organisms, there is an urgent need for novel quantitative methods with which to study this process. Here, we describe a flow cytometry-based approach to determine mitophagy by using MitoTracker Deep Red, a widely used mitochondria-selective probe. Used in combination with selective inhibitors it may allow for the determination of mitophagy flux. Here, we test the validity of the use of this method in cell lines and in primary cell and tissue cultures.
Topics: Amino Acids; Animals; Carbonyl Cyanide m-Chlorophenyl Hydrazone; Disease Models, Animal; Down-Regulation; Embryo, Mammalian; Fibroblasts; Flavonoids; Flavonols; Flow Cytometry; HeLa Cells; Humans; Lysosomes; Mice, Inbred C57BL; Mitochondria; Mitophagy; Niacinamide; Retina; Retinitis Pigmentosa
PubMed: 25945953
DOI: 10.1080/15548627.2015.1034403 -
Cell Reports Dec 2023Selective autophagy mediates the removal of harmful material from the cytoplasm. This cargo material is selected by cargo receptors, which orchestrate its sequestration...
Selective autophagy mediates the removal of harmful material from the cytoplasm. This cargo material is selected by cargo receptors, which orchestrate its sequestration within double-membrane autophagosomes and subsequent lysosomal degradation. The cargo receptor p62/SQSTM1 is present in cytoplasmic condensates, and a fraction of them are constantly delivered into lysosomes. However, the molecular composition of the p62 condensates is incompletely understood. To obtain insights into their composition, we develop a method to isolate these condensates and find that p62 condensates are enriched in components of the translation machinery. Furthermore, p62 interacts with translation initiation factors, and eukaryotic initiation factor 2α (eIF2α) and eIF4E are degraded by autophagy in a p62-dependent manner. Thus, p62-mediated autophagy may in part be linked to down-regulation of translation initiation. The p62 condensate isolation protocol developed here may facilitate the study of their contribution to cellular quality control and their roles in health and disease.
Topics: Humans; HEK293 Cells; RNA-Binding Proteins; Biomolecular Condensates; Eukaryotic Initiation Factor-2; Eukaryotic Initiation Factor-4E; Autophagy; Wortmannin
PubMed: 38096057
DOI: 10.1016/j.celrep.2023.113583 -
Frontiers in Pharmacology 2022Viral myocarditis is caused by infection with viruses or bacteria, including coxsackievirus B3 (CVB3), and is characterized by acute or chronic inflammatory responses in... (Review)
Review
Viral myocarditis is caused by infection with viruses or bacteria, including coxsackievirus B3 (CVB3), and is characterized by acute or chronic inflammatory responses in the heart. The mortality associated with severe viral myocarditis is considerable. In some patients, viral myocarditis may develop into dilated cardiomyopathy or heart failure. Autophagy is involved in a wide range of physiological processes, including viral infection and replication. In the present review, we focus on the responses of cardiac tissues, cardiomyocytes, and cardiac fibroblasts to CVB3 infection. Subsequently, the effects of altered autophagy on the development of viral myocarditis are discussed. Finally, this review also examined and assessed the use of several popular autophagy modulating drugs, such as metformin, resveratrol, rapamycin, wortmannin, and 3-methyladenine, as alternative treatment strategies for viral myocarditis.
PubMed: 35479306
DOI: 10.3389/fphar.2022.843103 -
Frontiers in Molecular Neuroscience 2023Despite its role in inflammation and the redox system under hypoxia, the effects and molecular mechanisms of hypoxia-inducible factor (HIF) in...
BACKGROUND
Despite its role in inflammation and the redox system under hypoxia, the effects and molecular mechanisms of hypoxia-inducible factor (HIF) in neuroinflammation-associated depression are poorly explored. Furthermore, Prolyl hydroxylase domain-containing proteins (PHDs) regulate HIF-1; however, whether and how PHDs regulate depressive-like behaviors under Lipopolysaccharides (LPS)-induced stress conditions remain covered.
METHODS
To highlight the roles and underlying mechanisms of PHDs-HIF-1 in depression, we employed behavioral, pharmacological, and biochemical analyses using the LPS-induced depression model.
RESULTS
Lipopolysaccharides treatment induced depressive-like behaviors, as we found, increased immobility and decreased sucrose preference in the mice. Concurrently, we examined increased cytokine levels, HIF-1 expression, mRNA levels of PHD1/PHD2, and neuroinflammation upon LPS administration, which Roxadustat reduced. Furthermore, the PI3K inhibitor wortmannin reversed Roxadustat-induced changes. Additionally, Roxadustat treatment attenuated LPS-induced synaptic impairment and improved spine numbers, ameliorated by wortmannin.
CONCLUSION
Lipopolysaccharides-dysregulates HIF-PHDs signaling may contribute to neuroinflammation-coincides depression PI3K signaling.
PubMed: 37008780
DOI: 10.3389/fnmol.2023.1048985 -
Pathogens (Basel, Switzerland) Aug 2023() is an infectious parasite that is prevalent worldwide in poultry and can cause death in both poultry and wild birds. Although studies have shown that damages host...
() is an infectious parasite that is prevalent worldwide in poultry and can cause death in both poultry and wild birds. Although studies have shown that damages host cells through direct contact, the mechanism is still unclear. In this study, we found that can kill host cells by ingesting fragments of the host cells, that is, by trogocytosis. Moreover, we found that the PI3K inhibitor wortmannin and the cysteine protease inhibitor E-64D prevented from destroying host cells. To the best of our knowledge, our study has demonstrated for the first time that uses trogocytosis to kill host cells. Understanding this mechanism is crucial for the prevention and control of avian trichomoniasis and will contribute to the development of vaccines and drugs for the prevention and control of avian trichomoniasis.
PubMed: 37623968
DOI: 10.3390/pathogens12081008 -
Frontiers in Oncology 2022The anti-tumour effect of Huaier has been demonstrated in a variety of tumours. Ferroptosis is a newly identified type of programmed cell death accompanied by the...
PURPOSE
The anti-tumour effect of Huaier has been demonstrated in a variety of tumours. Ferroptosis is a newly identified type of programmed cell death accompanied by the accumulation of reactive oxygen species (ROS) and iron in cells and plays a key role in the therapeutic process against malignant tumours. We aimed to explore the potential therapeutic role of Huaier in pancreatic cancer and uncover the relationship between Huaier and ferroptosis.
METHODS
CCK8 and colony formation assays were used to determine the proliferation of pancreatic cancer cells (PCs). The levels of cellular ROS were analysed by a fluorescence probe, and the accumulation of cellular iron was showed by Prussian blue staining. The autophagosomes and mitochondrial morphology were characterised by transmission electron microscopy (TEM). The levels of intracellular glutathione (GSH) and lipid peroxidation were measured by the corresponding kits.
RESULTS
The growth inhibitory effect of Huaier on PCs was concentration- and time-dependent, but this effect was significantly attenuated by ferroptosis inhibitors. In addition, Huaier effectively inhibited the GSH-GPX4 antioxidation system and resulted in the massive accumulation of ROS in PCs As shown by TEM, Huaier-treated PCs exhibited a decrease in mitochondrial cristae and a smaller mitochondrion, accompanied by an increase in autophagosomes. Indeed, we found that autophagy can induce ferroptosis in PCs and that Huaier-induced ferroptosis can be suppressed by the autophagosome inhibitor, Wortmannin.
CONCLUSION
Huaier can activate ferroptosis by inducing autophagy in PCs.
PubMed: 36248959
DOI: 10.3389/fonc.2022.960858 -
World Journal of Clinical Oncology Oct 2016The Akt signal transduction pathway controls most hallmarks of cancer. Activation of the Akt cascade promotes a malignant phenotype and is also widely implicated in drug... (Review)
Review
The Akt signal transduction pathway controls most hallmarks of cancer. Activation of the Akt cascade promotes a malignant phenotype and is also widely implicated in drug resistance. Therefore, the modulation of Akt activity is regarded as an attractive strategy to enhance the efficacy of cancer therapy and irradiation. This pathway consists of phosphatidylinositol 3 kinase (PI3K), mammalian target of rapamycin, and the transforming serine-threonine kinase Akt protein isoforms, also known as protein kinase B. DNA-targeted agents, such as platinum agents, taxanes, and antimetabolites, as well as radiation have had a significant impact on cancer treatment by affecting DNA replication, which is aberrantly activated in malignancies. However, the caveat is that they may also trigger the activation of repairing mechanisms, such as upstream and downstream cascade of Akt survival pathway. Thus, each target can theoretically be inhibited in view of improving the potency of conventional treatment. Akt inhibitors, ., MK-2206 and perifosine, or PI3K modulators, ., LY294002 and Wortmannin, have shown some promising results in favor of sensitizing the cancer cells to the therapy and , which have provided the rationale for incorporation of these novel agents into multimodality treatment of different malignancies. Nevertheless, despite the acceptable safety profile of some of these agents in the clinical studies, with regard to the efficacy, the results are still too preliminary. Hence, we need to wait for the upcoming data from the ongoing trials before utilizing them into the standard care of cancer patients.
PubMed: 27777878
DOI: 10.5306/wjco.v7.i5.352 -
Medicinal Research Reviews Sep 2015Although fungi produce highly structurally diverse metabolites, many of which have served as excellent sources of pharmaceuticals, no fungi-derived agent has been... (Review)
Review
Although fungi produce highly structurally diverse metabolites, many of which have served as excellent sources of pharmaceuticals, no fungi-derived agent has been approved as a cancer drug so far. This is despite a tremendous amount of research being aimed at the identification of fungal metabolites with promising anticancer activities. This review discusses the results of clinical testing of fungal metabolites and their synthetic derivatives, with the goal to evaluate how far we are from an approved cancer drug of fungal origin. Also, because in vivo studies in animal models are predictive of the efficacy and toxicity of a given compound in a clinical situation, literature describing animal cancer testing of compounds of fungal origin is reviewed as well. Agents showing the potential to advance to clinical trials are also identified. Finally, the technological challenges involved in the exploitation of fungal biodiversity and procurement of sufficient quantities of clinical candidates are discussed, and potential solutions that could be pursued by researchers are highlighted.
Topics: Androstadienes; Animals; Antineoplastic Agents; Aphidicolin; Biological Products; Clinical Trials as Topic; Cyclohexanes; Diketopiperazines; Disease Models, Animal; Drug Design; Drug Resistance, Neoplasm; Fatty Acids, Unsaturated; Female; Fungi; Humans; Macrolides; Male; Mice; Neoplasms; Polycyclic Sesquiterpenes; Sesquiterpenes; Trichothecenes; Wortmannin
PubMed: 25850821
DOI: 10.1002/med.21348 -
American Journal of Translational... 2021The aim of this study was to show the effects of autophagy inhibitor Wortmannin and antiangiogenic-proapoptotic Thalidomide on autophagy and apoptosis markers in 4T1...
The aim of this study was to show the effects of autophagy inhibitor Wortmannin and antiangiogenic-proapoptotic Thalidomide on autophagy and apoptosis markers in 4T1 breast cancer cells in vitro and in vivo. The half-maximal inhibitory concentration (IC50) values of 4T1 cells for Wortmannin and Thalidomide were evaluated by Methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay. After cancer formation in 28 BALB/C female mice, drugs were administered for seven days. Cells and tissue sections were evaluated for anti-phosphoinositide 3-kinase (PI3K), anti- the microtubule-associated protein 1 light chain3 (MAPLC3β), anti-caspase 8, anti-caspase 9, and anti-caspase 3 immunoreactivities by immunohistochemical staining and apoptosis by Terminal Transferase dUTP Nick End Labeling (TUNEL) assay. Both PI3K and MAPLC3β immunoreactivities decreased in all treatments when compared to control group except Thalidomide treatment in primary cancer tissue. The caspase 3, 8, and 9 immunoreactivities were increased in all treatment groups and TUNEL positive cells were the highest in the Wortmannin and Thalidomide group. Our findings suggest that autophagy is an important mechanism for 4T1 cells and both Wortmannin and Thalidomide treatments inhibit autophagy and induce apoptosis. In primary cancer tissues, autophagy was not effective as in vitro. The treatment of Wortmannin and Thalidomide increased the apoptotic cells in vivo independent from autophagy inhibition. Different results may be because of microenvironment. Further studies must be done to elucidate the effect of microenvironment.
PubMed: 34306363
DOI: No ID Found