scholarly journals LPS Mediates Bovine Endometrial Epithelial Cell Pyroptosis Directly Through Both NLRP3 Classical and Non-Classical Inflammasome Pathways

2021 ◽  
Vol 12 ◽  
Author(s):  
Xiaoyu Ma ◽  
Yajuan Li ◽  
Wenxiang Shen ◽  
Ayodele Olaolu Oladejo ◽  
Jie Yang ◽  
...  
Keyword(s):  
Cell Death ◽  
Plasma Membrane ◽  
Epithelial Cell ◽  
Cell Swelling ◽  
Endometrial Epithelial Cell ◽  
Membrane Rupture ◽  
Caspase 1 ◽  
Vector Construction ◽  
Mrna And Protein Expression

As a highly inflammatory form of programmed cell death, pyroptosis is triggered by pro-inflammatory signals and associated with inflammation. It is characterized by cell swelling and large bubbles emerging from the plasma membrane, which release cytokines during inflammation. Compared with other types of cell death, pyroptosis has a distinct morphology and mechanism and involves special inflammasome cascade pathways. However, the inflammasome mechanism through which endometrial epithelial cell pyroptosis occurs in LPS-mediated inflammation remains unclear. We confirmed that there was an increased mRNA and protein expression of the IL-6, TNF-α, IL-1β, IL-18 cytokines, the inflammasome molecules NLRP3, CASPASE-1, CASPASE-4, and GSDMD in LPS-induced primary bovine endometrial epithelial cells (BEECs) in an in vitro established inflammatory model using ELISA, real-time PCR (RT-PCR), vector construction and transfection, and Western blotting. Scanning electron microscopy and lactate dehydrogenase (LDH) activity assays revealed induced cell membrane rupture, which is the main characteristic of pyroptosis. In conclusion, the cytolytic substrate GSDMD’s cleavage by caspase-1 or caspase-4 through the NLRP3 classical and non-classical inflammasome pathways, GSDMD N-terminus bind to the plasma membrane to form pores and release IL -18, IL-1β cause cell death during LPS induced BEECs inflammation.

scholarly journals NINJ1 mediates plasma membrane rupture during lytic cell death

2020 ◽  
Author(s):  
Nobuhiko Kayagaki ◽  
Opher Kornfeld ◽  
Bettina Lee ◽  
Irma Stowe ◽  
Karen O'Rourke ◽  
...  
Keyword(s):  
Cell Death ◽  
Plasma Membrane ◽  
Apoptotic Cell ◽  
High Mobility ◽  
Surface Protein ◽  
Underlying Mechanism ◽  
Cell Swelling ◽  
Membrane Pore ◽  
Membrane Rupture ◽  
Ionic Fluxes

Abstract Plasma membrane rupture (PMR) is the final cataclysmic event in lytic cell death. PMR releases intracellular molecules termed damage-associated molecular patterns (DAMPs) that propagate the inflammatory response. The underlying mechanism for PMR, however, is unknown. Here we show that the ill-characterized nerve injury-induced protein 1 (NINJ1) — a cell surface protein with two transmembrane regions — plays an essential role in the induction of PMR. A forward-genetic screen of randomly mutagenized mice linked NINJ1 to PMR. Ninj1–/– macrophages exhibited impaired PMR in response to diverse inducers of pyroptotic, necrotic and apoptotic cell death, and failed to release numerous intracellular proteins including High Mobility Group Box 1 (HMGB1, a known DAMP) and Lactate Dehydrogenase (LDH, a standard measure of PMR). Ninj1–/– macrophages died, but with a distinctive and persistent ballooned morphology, attributable to defective disintegration of bubble-like herniations. Ninj1–/– mice were more susceptible than wild-type mice to Citrobacter rodentium, suggesting a role for PMR in anti-bacterial host defense. Mechanistically, NINJ1 utilized an evolutionarily conserved extracellular α-helical domain for oligomerization and subsequent PMR. The discovery of NINJ1 as a mediator of PMR overturns the long-held dogma that cell death-related PMR is a passive event. Pyroptosis is a potent inflammatory mode of lytic cell death triggered by diverse infectious and sterile insults1-3. It is driven by the pore-forming fragment of gasdermin D (GSDMD)4-7 and releases two exemplar proteins: interleukin-1β (IL-1β), a pro-inflammatory cytokine, and LDH, a standard marker of PMR and lytic cell death. An early landmark study8 predicted two sequential steps for pyroptosis: (1) initial formation of a small plasma membrane pore causing IL-1β release and non-selective ionic fluxes, and (2) subsequent PMR attributable to oncotic cell swelling. PMR releases LDH (140 kDa) and large DAMPs. While the predicted size of gasdermin pores (~18 nm inner diameter9) is large enough to release IL-1β (17 kDa, ~4.5 nm diameter), the underlying mechanism for subsequent PMR has been considered a passive osmotic lysis event.

scholarly journals Palmitate aggravates proteinuria-induced cell death and inflammation via CD36-inflammasome axis in the proximal tubular cells of obese mice

2018 ◽  
Vol 315 (6) ◽  
pp. F1720-F1731 ◽  
Author(s):  
Lung-Chih Li ◽  
Jenq-Lin Yang ◽  
Wen-Chin Lee ◽  
Jin-Bor Chen ◽  
Chien-Te Lee ◽  
...  
Keyword(s):  
Cell Death ◽  
Tubular Injury ◽  
Proximal Tubular Cells ◽  
Tubular Cells ◽  
Renal Tubular Cells ◽  
Caspase 1 ◽  
Proximal Tubular ◽  
Renal Tubular ◽  
Nlrp3 Inflammasomes

High levels of serum free fatty acids (FFAs) and proteinuria have been implicated in the pathogenesis of obesity-related nephropathy. CD36, a class B scavenger receptor, is highly expressed in the renal proximal tubules and mediates FFA uptake. It is not clear whether FFA- and proteinuria-mediated CD36 activation coordinates NLRP3 inflammasomes to induce renal tubular injury and inflammation. In this study, we investigated the roles of CD36 and NLRP3 inflammasomes in FFA-induced renal injury in high-fat diet (HFD)-induced obesity. HFD-fed C57BL/6 mice and palmitate-treated HK2 renal tubular cells were used as in vivo and in vitro models. Immunohistochemical staining showed that CD36, IL-1β, and IL-18 levels increased progressively in the kidneys of HFD-fed mice. Sulfo- N-succinimidyl oleate (SSO), a CD36 inhibitor, attenuated the HFD-induced upregulation of NLRP3, IL-1β, and IL-18 and suppressed the colocalization of NLRP3 and ASC in renal tubular cells. In vitro, SSO abolished the palmitate-induced activation of IL-1β, IL-18, and caspase-1 in HK2 proximal tubular cells. Furthermore, treatment with SSO and the knockdown of caspase-1 expression by siRNA both inhibited palmitate-induced cell death and apoptosis in HK2 cells. Collectively, palmitate causes renal tubular inflammation, cell death, and apoptosis via the CD36/NLRP3/caspase-1 axis, which may explain, at least in part, the mechanism underlying FFA-related renal tubular injury. The blockade of CD36-induced cellular processes is therefore a promising strategy for treating obesity-related nephropathy.

scholarly journals The Multifaceted Roles of Pyroptotic Cell Death Pathways in Cancer

Cancers ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1313
Author(s):  
Man Wang ◽  
Shuai Jiang ◽  
Yinfeng Zhang ◽  
Peifeng Li ◽  
Kun Wang
Keyword(s):  
Cell Death ◽  
Biological Significance ◽  
Chemotherapeutic Agents ◽  
The Body ◽  
Cell Swelling ◽  
Pathogen Invasion ◽  
Membrane Rupture ◽  
Cancer Management ◽  
Cell Death Pathways ◽  
Cancer Pathogenesis

Cancer is a category of diseases involving abnormal cell growth with the potential to invade other parts of the body. Chemotherapy is the most widely used first-line treatment for multiple forms of cancer. Chemotherapeutic agents act via targeting the cellular apoptotic pathway. However, cancer cells usually acquire chemoresistance, leading to poor outcomes in cancer patients. For that reason, it is imperative to discover other cell death pathways for improved cancer intervention. Pyroptosis is a new form of programmed cell death that commonly occurs upon pathogen invasion. Pyroptosis is marked by cell swelling and plasma membrane rupture, which results in the release of cytosolic contents into the extracellular space. Currently, pyroptosis is proposed to be an alternative mode of cell death in cancer treatment. Accumulating evidence shows that the key components of pyroptotic cell death pathways, including inflammasomes, gasdermins and pro-inflammatory cytokines, are involved in the initiation and progression of cancer. Interfering with pyroptotic cell death pathways may represent a promising therapeutic option for cancer management. In this review, we describe the current knowledge regarding the biological significance of pyroptotic cell death pathways in cancer pathogenesis and also discuss their potential therapeutic utility.

scholarly journals Gadd45α activity is the principal effector of Shigella mitochondria-dependent epithelial cell death in vitro and ex vivo

2011 ◽  
Vol 2 (2) ◽  
pp. e122-e122 ◽  
Author(s):  
L Lembo-Fazio ◽  
G Nigro ◽  
G Noël ◽  
G Rossi ◽  
F Chiara ◽  
...  
Keyword(s):  
Cell Death ◽  
Epithelial Cell ◽  
Ex Vivo ◽  
Epithelial Cell Death

scholarly journals The Card19 locus of murine chromosome 13 regulates terminal cell lysis downstream of caspase activation and Gasdermin-D cleavage

2021 ◽  
Author(s):  
Elisabet Bjanes ◽  
Reyna Garcia Sillas ◽  
Rina Matsuda ◽  
Benjamin Demarco ◽  
Timothée Fettrelet ◽  
...  
Keyword(s):  
Cell Death ◽  
Plasma Membrane ◽  
Cell Lysis ◽  
Terminal Cell ◽  
Snp Analysis ◽  
Caspase Activation ◽  
Chromosome 13 ◽  
Murine Chromosome ◽  
Membrane Rupture ◽  
Yersinia Infection

Cell death plays a critical role in inflammatory responses. During pyroptosis, inflammatory caspases cleave Gasdermin D (GSDMD) to release an N-terminal fragment that generates plasma membrane pores that mediate cell lysis and IL-1 cytokine release. Terminal cell lysis and IL-1β release following caspase activation can be uncoupled in certain cell types or in response to particular stimuli, a state termed hyperactivation. However, the factors and mechanisms that regulate terminal cell lysis downstream of GSDMD cleavage remain poorly understood. In the course of studies to define regulation of pyroptosis during Yersinia infection, we identified a line of Card19-/- mice whose macrophages were protected from cell death and showed reduced pore formation during apoptosis or pyroptosis, yet had wild-type levels of caspase activation, IL-1 secretion, and GSDMD cleavage. Unexpectedly, CARD19, a mitochondrial CARD-containing protein, was not directly responsible for this, as two independently-generated CRISPR/Cas9 Card19 knockout mice showed no defect in macrophage cell lysis. The original Card19-/- line was generated in a 129SvEvBrd background, and SNP analysis revealed a six megabase region of 129 origin co-segregating with the Card19 locus. Card19 is located on chromosome 13, adjacent to Ninj1, which was recently reported to regulate cell lysis downstream of GSDMD activation. Nonetheless, we could not detect major defects in NINJ1 protein expression or mutations in Ninj1 coding sequence in Card19-/- mice. Mice from the original Card19-/- line exhibited significantly increased susceptibility to Yersinia infection, demonstrating that cell lysis itself plays a key role in protection against bacterial infection. Our findings identify a locus on murine chromosome 13 that regulates the ability of macrophages to undergo plasma membrane rupture downstream of gasdermin cleavage, and implicates additional NINJ1-independent factors that control terminal cell lysis.

scholarly journals Genetic targeting of Card19 is linked to disrupted NINJ1 expression, impaired cell lysis, and increased susceptibility to Yersinia infection

2021 ◽  
Vol 17 (10) ◽  
pp. e1009967
Author(s):  
Elisabet Bjanes ◽  
Reyna Garcia Sillas ◽  
Rina Matsuda ◽  
Benjamin Demarco ◽  
Timothée Fettrelet ◽  
...  
Keyword(s):  
Cell Death ◽  
Plasma Membrane ◽  
Inflammatory Responses ◽  
Critical Role ◽  
Cell Lysis ◽  
Terminal Cell ◽  
Caspase Activation ◽  
Membrane Rupture ◽  
Genetic Targeting ◽  
Increased Susceptibility

Cell death plays a critical role in inflammatory responses. During pyroptosis, inflammatory caspases cleave Gasdermin D (GSDMD) to release an N-terminal fragment that generates plasma membrane pores that mediate cell lysis and IL-1 cytokine release. Terminal cell lysis and IL-1β release following caspase activation can be uncoupled in certain cell types or in response to particular stimuli, a state termed hyperactivation. However, the factors and mechanisms that regulate terminal cell lysis downstream of GSDMD cleavage remain poorly understood. In the course of studies to define regulation of pyroptosis during Yersinia infection, we identified a line of Card19-deficient mice (Card19lxcn) whose macrophages were protected from cell lysis and showed reduced apoptosis and pyroptosis, yet had wild-type levels of caspase activation, IL-1 secretion, and GSDMD cleavage. Unexpectedly, CARD19, a mitochondrial CARD-containing protein, was not directly responsible for this, as an independently-generated CRISPR/Cas9 Card19 knockout mouse line (Card19Null) showed no defect in macrophage cell lysis. Notably, Card19 is located on chromosome 13, immediately adjacent to Ninj1, which was recently found to regulate cell lysis downstream of GSDMD activation. RNA-seq and western blotting revealed that Card19lxcn BMDMs have significantly reduced NINJ1 expression, and reconstitution of Ninj1 in Card19lxcn immortalized BMDMs restored their ability to undergo cell lysis in response to caspase-dependent cell death stimuli. Card19lxcn mice exhibited increased susceptibility to Yersinia infection, whereas independently-generated Card19Null mice did not, demonstrating that cell lysis itself plays a key role in protection against bacterial infection, and that the increased infection susceptibility of Card19lxcn mice is attributable to loss of NINJ1. Our findings identify genetic targeting of Card19 being responsible for off-target effects on the adjacent gene Ninj1, disrupting the ability of macrophages to undergo plasma membrane rupture downstream of gasdermin cleavage and impacting host survival and bacterial control during Yersinia infection.

Sign in / Sign up

Export Citation Format

Share Document