Bilirubin enhances the activity of ASIC channels to exacerbate neurotoxicity in neonatal hyperbilirubinemia in mice

2020 ◽  
Vol 12 (530) ◽  
pp. eaax1337 ◽  
Author(s):  
Ke Lai ◽  
Xing-Lei Song ◽  
Hao-Song Shi ◽  
Xin Qi ◽  
Chun-Yan Li ◽  
...  
Keyword(s):  
Cell Death ◽  
Cerebrospinal Fluid ◽  
Lactate Dehydrogenase ◽  
Neonatal Hyperbilirubinemia ◽  
Bilirubin Concentration ◽  
Acid Sensing Ion Channels ◽  
Intracellular Ca ◽  
Prevailing View

Neonatal hyperbilirubinemia is a common clinical condition that can lead to brain encephalopathy, particularly when concurrent with acidosis due to infection, ischemia, and hypoxia. The prevailing view is that acidosis increases the permeability of the blood-brain barrier to bilirubin and exacerbates its neurotoxicity. In this study, we found that the concentration of the cell death marker, lactate dehydrogenase (LDH) in cerebrospinal fluid (CSF), is elevated in infants with both hyperbilirubinemia and acidosis and showed stronger correlation with the severity of acidosis rather than increased bilirubin concentration. In mouse neonatal neurons, bilirubin exhibits limited toxicity but robustly potentiates the activity of acid-sensing ion channels (ASICs), resulting in increases in intracellular Ca2+ concentration, spike firings, and cell death. Furthermore, neonatal conditioning with concurrent hyperbilirubinemia and hypoxia-induced acidosis promoted long-term impairments in learning and memory and complex sensorimotor functions in vivo, which are largely attenuated in ASIC1a null mice. These findings suggest that targeting acidosis and ASICs may attenuate neonatal hyperbilirubinemia complications.

scholarly journals Formation of Mallory Body-like Inclusions and Cell Death Induced by Deregulated Expression of Keratin 18

2002 ◽  
Vol 13 (10) ◽  
pp. 3441-3451 ◽  
Author(s):  
Ikuo Nakamichi ◽  
Shigetsugu Hatakeyama ◽  
Keiichi I. Nakayama
Keyword(s):  
Cell Death ◽  
Important Determinant ◽  
Cellular Model ◽  
Microtubule Network ◽  
Cytoplasmic Inclusions ◽  
Mallory Bodies ◽  
Keratin 18 ◽  
Intracellular Aggregates

Mallory bodies (MBs) are cytoplasmic inclusions that contain keratin 8 (K8) and K18 and are present in hepatocytes of individuals with alcoholic liver disease, nonalcoholic steatohepatitis, or benign or malignant hepatocellular neoplasia. Mice fed long term with griseofulvin are an animal model of MB formation. However, the lack of a cellular model has impeded understanding of the molecular mechanism of this process. Culture of HepG2 cells with griseofulvin has now been shown to induce both the formation of intracellular aggregates containing K18 as well as an increase in the abundance of K18 mRNA. Overexpression of K18 in HepG2, HeLa, or COS-7 cells also induced the formation of intracellular aggregates that stained with antibodies to ubiquitin and with rhodamine B (characteristics of MBs formed in vivo), eventually leading to cell death. The MB-like aggregates were deposited around centrosomes and disrupted the microtubular array. Coexpression of K8 with K18 restored the normal fibrous pattern of keratin distribution and reduced the toxicity of K18. In contrast, an NH2-terminal deletion mutant of K8 promoted the formation of intracellular aggregates even in the absence of K18 overexpression. Deregulated expression of K18, or an imbalance between K8 and K18, may thus be an important determinant of MB formation, which compromises the function of centrosomes and the microtubule network and leads to cell death.

scholarly journals Efficacy, long-term toxicity, and mechanistic studies of gold nanorods photothermal therapy of cancer in xenograft mice

2017 ◽  
Vol 114 (15) ◽  
pp. E3110-E3118 ◽  
Author(s):  
Moustafa R. K. Ali ◽  
Mohammad Aminur Rahman ◽  
Yue Wu ◽  
Tiegang Han ◽  
Xianghong Peng ◽  
...  
Keyword(s):  
Cell Death ◽  
Mechanism Of Action ◽  
Gold Nanorods ◽  
Photothermal Therapy ◽  
Near Infrared ◽  
Infrared Light ◽  
Mouse Tumor ◽  
Maximal Induction

Gold nanorods (AuNRs)-assisted plasmonic photothermal therapy (AuNRs-PPTT) is a promising strategy for combating cancer in which AuNRs absorb near-infrared light and convert it into heat, causing cell death mainly by apoptosis and/or necrosis. Developing a valid PPTT that induces cancer cell apoptosis and avoids necrosis in vivo and exploring its molecular mechanism of action is of great importance. Furthermore, assessment of the long-term fate of the AuNRs after treatment is critical for clinical use. We first optimized the size, surface modification [rifampicin (RF) conjugation], and concentration (2.5 nM) of AuNRs and the PPTT laser power (2 W/cm2) to achieve maximal induction of apoptosis. Second, we studied the potential mechanism of action of AuNRs-PPTT using quantitative proteomic analysis in mouse tumor tissues. Several death pathways were identified, mainly involving apoptosis and cell death by releasing neutrophil extracellular traps (NETs) (NETosis), which were more obvious upon PPTT using RF-conjugated AuNRs (AuNRs@RF) than with polyethylene glycol thiol-conjugated AuNRs. Cytochrome c and p53-related apoptosis mechanisms were identified as contributing to the enhanced effect of PPTT with AuNRs@RF. Furthermore, Pin1 and IL18-related signaling contributed to the observed perturbation of the NETosis pathway by PPTT with AuNRs@RF. Third, we report a 15-month toxicity study that showed no long-term toxicity of AuNRs in vivo. Together, these data demonstrate that our AuNRs-PPTT platform is effective and safe for cancer therapy in mouse models. These findings provide a strong framework for the translation of PPTT to the clinic.

In vivo imaging of myocardial cell death using a peptide probe and assessment of long-term heart function

2013 ◽  
Vol 172 (1) ◽  
pp. 367-373 ◽  
Author(s):  
Bodhraj Acharya ◽  
Kai Wang ◽  
In-San Kim ◽  
WoongChol Kang ◽  
Chanil Moon ◽  
...  
Keyword(s):  
Cell Death ◽  
In Vivo Imaging ◽  
Heart Function ◽  
Myocardial Cell ◽  
Peptide Probe

Programmed cell death with a necrotic-like phenotype

2013 ◽  
Vol 4 (3) ◽  
pp. 259-275 ◽  
Author(s):  
Michael J. Morgan ◽  
Zheng-gang Liu
Keyword(s):  
Cell Death ◽  
Programmed Cell Death ◽  
Mammalian Development ◽  
Programmed Necrosis ◽  
Physiological Processes ◽  
Molecular Events ◽  
Regulated Necrosis

AbstractProgrammed cell death is the process by which an individual cell in a multicellular organism commits cellular ‘suicide’ to provide a long-term benefit to the organism. Thus, programmed cell death is important for physiological processes such as development, cellular homeostasis, and immunity. Importantly, in this process, the cell is not eliminated in response to random events but in response to an intricate and genetically defined set of internal cellular molecular events or ‘program’. Although the apoptotic process is generally very well understood, programmed cell death that occurs with a necrotic-like phenotype has been much less studied, and it is only within the past few years that the necrotic program has begun to be elucidated. Originally, programmed necrosis was somewhat dismissed as a nonphysiological phenomenon that occurs in vitro. Recent in vivo studies, however, suggest that regulated necrosis is an authentic classification of cell death that is important in mammalian development and other physiological processes, and programmed necrosis is now considered a significant therapeutic target in major pathological processes as well. Although the RIP1-RIP3-dependent necrosome complex is recognized as being essential for the execution of many instances of programmed necrosis, other downstream and related necrotic molecules and pathways are now being characterized. One of the current challenges is understanding how and under what conditions these pathways are linked together.

scholarly journals Mouse Hippocampal Organotypic Tissue Cultures Exposed to In Vitro “Ischemia” Show Selective and Delayed CA1 Damage that is Aggravated by Glucose

2003 ◽  
Vol 23 (1) ◽  
pp. 23-33 ◽  
Author(s):  
Anna Rytter ◽  
Tobias Cronberg ◽  
Fredrik Asztély ◽  
Sailasree Nemali ◽  
Tadeusz Wieloch
Keyword(s):  
Cell Death ◽  
Cerebrospinal Fluid ◽  
Cell Damage ◽  
Extracellular Fluid ◽  
Oxygen Deprivation ◽  
Tissue Cultures ◽  
Ion Composition ◽  
In Vitro Ischemia

Oxygen and glucose deprivation (OGD) in cell cultures is generally studied in a medium, such as artificial cerebrospinal fluid (CSF), with an ion composition similar to that of the extracellular fluid of the normal brain (2 to 4 mmol/L K+, 2 to 3 mmol/L Ca2+; pH 7.4). Because the distribution of ions across cell membranes dramatically shifts during ischemia, the authors exposed mouse organotypic hippocampal tissue cultures to OGD in a medium, an ischemic cerebrospinal fluid, with an ion composition similar to the extracellular fluid of the brain during ischemia in vivo (70 mmol/L K+, 0.3 mmol/L Ca2+; pH 6.8). In ischemic CSF, OGD induced a selective and delayed cell death in the CA1 region, as assessed by propidium iodide uptake. Cell death was glutamate receptor dependent since blockade of the N-methyl-D-aspartate and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors mitigated cell damage. Hyperglycemia aggravates ischemic brain damage in vivo, whereas in vitro glucose in artificial CSF prevents oxygen deprivation-induced damage. The authors demonstrate that glucose in ischemic CSF significantly exacerbates cell damage after oxygen deprivation. This new model of in vitro “ischemia” can be useful in future studies of the mechanisms and treatment of ischemic cell death, including studies using genetically modified mice.

Effects of prostaglandin F2α and other potential secretagogues on oxytocin secretion and second messenger metabolism in the ovine corpus luteum in vitro

1990 ◽  
Vol 126 (1) ◽  
pp. 89-98 ◽  
Author(s):  
T. J. McCann ◽  
A. P. F. Flint
Keyword(s):  
Arachidonic Acid ◽  
Lactate Dehydrogenase ◽  
Calcium Ionophore ◽  
Prostaglandin F2α ◽  
Calcium Ionophore A23187 ◽  
Ionophore A23187 ◽  
Lactate Dehydrogenase Release ◽  
Intracellular Ca

ABSTRACT Release of oxytocin by sliced or minced sheep luteal tissue in vitro was stimulated up to 1·6- and 2·3-fold by arachidonic acid and the calcium ionophore A23187 respectively. Prostaglandin (PG) F2α and the PGF2α analogue cloprostenol, and other potential agonists known to be active in vivo, including noradrenaline and acetylcholine, were ineffective, as was the phorbol ester tetradecanoylphorbol acetate (TPA). The ineffectiveness of PGF2α was not due to a general unresponsiveness of the tissue in vitro, as PGF2α reduced LH stimulation of tissue concentrations of cyclic AMP and activated inositol lipid hydrolysis. The effect of arachidonic acid was accompanied by release from the tissue of the cytosolic enzyme lactate dehydrogenase (at arachidonic acid concentrations below those required to release oxytocin) and its effect on oxytocin and lactate dehydrogenase release was mimicked by oleic and linolenic acids; arachidonic acid was concluded to act by a non-physiological physicochemical effect without conversion to an eicosanoid. As PGF2α in vitro is known to raise intracellular Ca2+ concentrations in the large luteal cells that secrete oxytocin, and as A23187 stimulates oxytocin release in vitro in the presence and absence of TPA, it is concluded that in-vitro incubation results in an artifactual blockade of the oxytocin-releasing action of PGF2α at an unidentified point distal to the effect on intracellular Ca2+. Journal of Endocrinology (1990) 126, 89–98

scholarly journals Fructose-a double edged sword for cell death versus differentiation and long-term survival of NSC-34 motor neuron like cells in vitro

2021 ◽  
Author(s):  
Divya Lodha ◽  
Jamuna R. Subramaniam
Keyword(s):  
Cell Proliferation ◽  
Cell Death ◽  
Motor Neurons ◽  
Response Regulator ◽  
Nuclear Staining ◽  
Term Survival ◽  
High Fructose

Abstract In various neurological and neurodegenerative diseases (ND), motor neurons (MN) of the spinal cord are affected leading to movement impairments. The ND, Amyotrophic Lateral Sclerosis (ALS), is caused due to MN degeneration. ALS afflicts athletes and other major sports personalities, who generally consume fructose enriched sports drinks. Recently, we have reported that high fructose (F5%) impairs the metabolic activity in the NSC-34, MN cell line and reduces the healthspan of C. elegans. But how fructose impacts the MNs either in vitro or in vivo in the long term is not understood. Here we report, to our surprise, that high fructose (F5%) treatment of NSC-34 leads to differentiation of 1-2% of cells with progressive neurite extension. They could be maintained for 80 days in vitro with 5% CO2 and O2 at 18.8%. On the contrary, 5% fructose significantly reduced cell viability by ~85% and inhibited cell proliferation by Day10. Nuclear staining displayed multiple nuclei in the cells indicative of cytokinesis inhibition which led to the lack of cell proliferation. Further, F5% significantly increased ROS levels (^~34%), the potential cause for reduced viability. In addition, no induction of expression of the master oxidative stress response regulator, the transcription factor, nrf-2, or the downstream effector, sod1, was evident. Despite the adverse effects, in the absence of any, F5% is a potential strategy to maintain at least a small percentage of MNs for a long time, ~45 days in vitro, which also reinforces the Redox-Cell death versus cell survival conundrum.

The HIF-1 response to simulated ischemia in mouse skeletal muscle cells neither enhances glycolysis nor prevents myotube cell death

2007 ◽  
Vol 293 (4) ◽  
pp. R1693-R1701 ◽  
Author(s):  
Nathalie Dehne ◽  
Uta Kerkweg ◽  
Teresa Otto ◽  
Joachim Fandrey
Keyword(s):  
Skeletal Muscle ◽  
Cell Death ◽  
Lactate Dehydrogenase ◽  
Pyruvate Kinase ◽  
Muscle Cells ◽  
Skeletal Muscle Cells ◽  
Vegf Mrna ◽  
Isolated Cells ◽  
Simulated Ischemia

Hypoxia-inducible factor (HIF) plays an important role in regulating gene expression in response to ischemia. Although activation of HIF-1 in muscle tissue was found during ischemia in vivo, the meaning and mechanisms in isolated cells are still incompletely understood. We studied activation of HIF-1 in skeletal muscle cells cultured in either their undifferentiated myoblast state or differentiated into myotubes. HIF-1 was activated in myoblasts and myotubes by hypoxia and simulated ischemia. Induction of adrenomedullin mRNA and, to a lesser extent, VEGF mRNA correlated well with the induction of HIF-1α protein in both cell types. Enzymes of glycolysis-like lactate dehydrogenase and pyruvate kinase showed upregulation of their mRNA only under hypoxic conditions but not during simulated ischemia. Phosphofructokinase mRNA showed no significant upregulation at all. Although HIF-1 was activated in myotubes during simulated ischemia, myotubes died preceded by a loss of ATP. Myoblasts survived simulated ischemia with no decrease in ATP or ATP turnover. Furthermore, pharmacological inhibition of HIF-1 hydroxylases by dimethyloxalylglycine (DMOG) increased HIF-1α accumulation and significantly upregulated the expression of adrenomedullin, VEGF, lactate dehydrogenase, and pyruvate kinase in myoblasts and myotubes. However, DMOG provided no protection from cell death. Our data indicate that HIF-1, although activated in myotubes during simulated ischemia, cannot protect against the loss of ATP and cell viability. In contrast, myoblasts survive ischemia and thus may play an important role during regeneration and HIF-1-induced revascularization.

scholarly journals Genipin Reverses HFD-Induced Liver Damage and Inhibits UCP2-Mediated Pyroptosis in Mice

2018 ◽  
Vol 49 (5) ◽  
pp. 1885-1897 ◽  
Author(s):  
Hong Zhong ◽  
Mengting Liu ◽  
Yaya Ji ◽  
Minjuan Ma ◽  
Kun Chen ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Death ◽  
Lactate Dehydrogenase ◽  
Liver Damage ◽  
Lipid Accumulation ◽  
Water Soluble ◽  
Morbidly Obese ◽  
Ldh Release

Background/Aims: Liver damage is a typical manifestation of nonalcoholic fatty liver disease (NAFLD). It originates from excessive fat accumulation, leading to hepatocyte death, inflammation, and fibrosis. Nonalcoholic steatohepatitis (NASH) is a type of NAFLD with a prevalence of 49% in morbidly obese patients. Pyroptosis plays an important role in the development of NASH; thus, it is important to elucidate the effect of lipid accumulation on pyroptosis. Genipin (GNP), a natural water-soluble cross-linking agent, has hepatoprotective effects and decreases lipid accumulation in the liver; however, the mechanisms underlying these effects are unknown. Methods: In this study, qPCR and Western blot were used to examine pyroptotic gene expression in high-fat diet (HFD) induced obese mice and free fatty acids (FFAs) treated hepatocytes. At the same time, relative lactate dehydrogenase (LDH) release and Hoechst & propidium iodide (PI) staining were done to verify cell death. To explore the molecular mechanism, cell transfection were constructed with siRNA or plasmid to obtain knockdown or overexpression hepatocytes. Results: We found that HFD-fed mice and FFAs-treated hepatocytes had obvious pyroptosis, and addition of GNP reversed liver damage and inhibited pyroptosis both in vitro and in vivo. Besides, UCP2 knockdown cells showed suppressed FFAs-mediated pyroptosis, as determined by decreased pyroptotic gene expression, reduced lactate dehydrogenase (LDH) release, and reduced cell death. Consistent with this, cells transfected with UCP2 had upregulated pyroptotic gene expression, increased LDH release, and increased cell death. Conclusion: GNP reverses HFD-induced liver damage and inhibits UCP2-mediated pyroptosis. Thus, GNP may serve as a potential therapeutic candidate for NAFLD.

Cerebrospinal fluid hydrodynamics after placement of a shunt with an antisiphon device: a long-term study

2001 ◽  
Vol 94 (5) ◽  
pp. 750-756 ◽  
Author(s):  
Bo Lundkvist ◽  
Anders Eklund ◽  
Bo Kristensen ◽  
Markku Fagerlund ◽  
Lars-Owe D. Koskinen ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Csf Shunt ◽  
Content Type ◽  
Long Term Study ◽  
Before And After ◽  
Cerebrospinal Fluid Hydrodynamics ◽  
Antisiphon Device ◽  
Fine Print

Object. Few studies have been performed to investigate the cerebrospinal fluid (CSF) hydrodynamic profile in patients with idiopathic adult hydrocephalus syndrome (IAHS) before and after shunt implantation. The authors compared the in vivo CSF hydrodynamic properties, including the degree of gravity-induced CSF flow, of a shunt with an antisiphon device with a standard shunt. Methods. Twelve patients with IAHS underwent insertion of shunts with Delta valves. Clinical testing, magnetic resonance imaging, and CSF hydrodynamic investigations were conducted with intracranial pressure (ICP), gravity effect, and pressure—flow curve of the shunt estimated at baseline and at 3 and 12 months postoperatively. No shunt was revised. Despite postoperative clinical improvement in all patients who received Delta valves, the mean ICP was only moderately reduced (mean decrease at 3 months 0.3 kPa [p = 0.02], at 12 months 0.2 kPa [not significant]). Patients with the greatest increase in ICP preoperatively had the most pronounced decrease postoperatively. The hydrostatic effect of the Delta valves was significantly lower than with the Hakim shunts (0.1–0.2 kPa compared with 0.6 kPa). The increased conductance (that is, lowered resistance) was up to 14 times higher with the Delta valves compared with preoperative levels. Conclusions. The function of a CSF shunt may be more complicated than previously thought; the subcutaneous pressure acting on the antisiphon device can modify the shunt characteristics. A compensatory increase in CSF production may counteract the increased outflow through the shunt. The improved CSF outflow conductance may increase the intracranial compliance and thereby dampen a pathological ICP waveform.

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