Involvement Of Caspase-1 Research Articles

The potency of blumeatin and luteolin as caspase-1 inhibitor by molecular docking

COVID-19 infection induces inflammation by increasing cytokines such as IL-1b, IL-6, IL-18, IFN-γ, and TNF-α. IL-1b is generated by the involvement of caspase-1. Therefore, caspase-1 inhibitor can be potential for inflammation therapy caused by COVID-19 infection. This study aims to determine the potential of blumeatin and luteolin as anti-inflammatory agents by inhibiting caspase-1 using a molecular docking approach. This study was carried out by caspase-1 (PDB ID: 1RWK) preparation, blumeatin and luteolin structure optimization, docking protocol validation, and docking of blumeatin and luteolin on caspase-1. Bluematin and luteolin had a binding affinity of -5,63 kcal/mol and -5,93 kcal/mol, lower than Q158 native ligand (-3.92 kcal/mol). Similar amino acid residues in hydrogen bonds interaction were observed between Q158 native ligand, blumeatin, and luteolin with caspase-1 (GLN 283 and ARG 179). Blumeatin and luteolin are potentially anti-inflammation agents through the inhibition of the caspase-1 in silico.

Involvement of caspase-1 in inflammasomes activation and bacterial clearance in S. aureus-infected osteoblast-like MG-63 cells.

Staphylococcus aureus, a versatile Gram-positive bacterium, is the main cause of bone and joint infections (BJI), which are prone to recurrence. The inflammasome is an immune signaling platform that assembles after pathogen recognition. It activates proteases, most notably caspase-1 that proteolytically matures and promotes the secretion of mature IL-1β and IL-18. The role of inflammasomes and caspase-1 in the secretion of mature IL-1β and in the defence of S. aureus-infected osteoblasts has not yet been fully investigated. We show here that S. aureus-infected osteoblast-like MG-63 but not caspase-1 knock-out CASP1 -/- MG-63 cells, which were generated using CRISPR-Cas9 technology, activate the inflammasome as monitored by the release of mature IL-1β. The effect was strain-dependent. The use of S. aureus deletion and complemented phenole soluble modulins (PSMs) mutants demonstrated a key role of PSMs in inflammasomes-related IL-1β production. Furthermore, we found that the lack of caspase-1 in CASP1 -/- MG-63 cells impairs their defense functions, as bacterial clearance was drastically decreased in CASP1 -/- MG-63 compared to wild-type cells. Our results demonstrate that osteoblast-like MG-63 cells play an important role in the immune response against S. aureus infection through inflammasomes activation and establish a crucial role of caspase-1 in bacterial clearance.

2090 POSSIBLE ROLE OF THE INFLAMMASOME IN ABNORMAL SEMEN QUALITY OF MEN WITH SPINAL CORD INJURY

You have accessJournal of UrologyInfertility: Physiology, Pathophysiology, Basic Research1 Apr 20122090 POSSIBLE ROLE OF THE INFLAMMASOME IN ABNORMAL SEMEN QUALITY OF MEN WITH SPINAL CORD INJURY Emad Ibrahim, Xianyang Zhang, Teodoro Aballa, Juan Pablo De Rivero Vaccari, Robert Keane, W. Dalton Dietrich, Charles Lynne, and Nancy Brackett Emad IbrahimEmad Ibrahim Miami, FL More articles by this author , Xianyang ZhangXianyang Zhang Miami, FL More articles by this author , Teodoro AballaTeodoro Aballa Miami, FL More articles by this author , Juan Pablo De Rivero VaccariJuan Pablo De Rivero Vaccari Miami, FL More articles by this author , Robert KeaneRobert Keane Miami, FL More articles by this author , W. Dalton DietrichW. Dalton Dietrich Miami, FL More articles by this author , Charles LynneCharles Lynne Miami, FL More articles by this author , and Nancy BrackettNancy Brackett Miami, FL More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.2257AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Most men with spinal cord injury (SCI) have normal sperm concentrations but abnormally low sperm motility. Elevated semen concentrations of inflammatory cytokines contribute to this problem. The mechanism leading to elevated semen cytokines in men with SCI is unknown. To understand if inflammasome pathways are part of the mechanism leading to elevated semen cytokines in men with SCI, this study investigated inflammasome complex proteins and end product cytokines in semen of SCI and control subjects. METHODS Semen samples were collected from 37 men with SCI and 39 healthy non-SCI men as control subjects. Penile vibratory stimulation and electroejaculation were utilized to collect semen samples from men with SCI. Control subjects collected semen by masturbation. Semen was divided into two aliquots. One aliquot was centrifuged to obtain seminal plasma (the supernatant). The other aliquot was processed on a density gradient to isolate sperm cells. Western blot analysis was used to detect concentrations of caspase-1 and apoptosis-associated speck-like protein containing a CARD (ASC), while immunocytochemistry with confocal microscopy localized these proteins on the sperm cell. Concentrations of caspase-1, IL-1β and IL-18 in the seminal plasma were determined by ELISA. RESULTS Concentrations of the following were elevated in the seminal plasma of SCI subjects compared to control subjects: caspase-1 (1187.0 ± 220.1 vs. 190.2 ± 39.0 pg/ml, p ≤ 0.0001); ASC (0.9792 ± 0.1340 vs. 0.1155 ± 0.0333 relative intensity, p ≤ 0.0001); IL-1β (92.6 ± 19.9 vs. 15.0 ± 4.1 pg/ml, p ≤ 0.0003); and IL-18 (2045.0 ± 729.1 vs. 64.9 ± 18.8 pg/ml, p ≤ 0.0087). Statistical analysis showed a positive correlation between the levels of caspase-1 and ASC in the seminal plasma (n=61, r2 = 0.42, p < 0.0001) and a negative correlation between sperm motility and the levels of ASC in the seminal plasma (n=62, r2 = 0.29, p < 0.0001). When examining sperm cell extracts by Western blot, ASC and caspase-1 were found to be elevated in SCI subjects compared to controls. The expression of these two proteins was further confirmed by immunocytochemistry with confocal microscopy. Caspase-1 was located in the head and the midpiece whereas ASC was located mainly in the proximal section of the sperm tail. CONCLUSIONS This study provides the first evidence of the inflammasome in human semen. The involvement of caspase-1 and ASC suggests an immunologic basis for abnormal semen quality in men with SCI. Inflammasome inactivation may be a possible target for therapeutic intervention. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e842-e843 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Emad Ibrahim Miami, FL More articles by this author Xianyang Zhang Miami, FL More articles by this author Teodoro Aballa Miami, FL More articles by this author Juan Pablo De Rivero Vaccari Miami, FL More articles by this author Robert Keane Miami, FL More articles by this author W. Dalton Dietrich Miami, FL More articles by this author Charles Lynne Miami, FL More articles by this author Nancy Brackett Miami, FL More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Caspase-1, Caspase-8, and Calpain Are Dispensable for IL-33 Release by Macrophages

In addition to IL-1 and IL-18, IL-33 was recently identified as a member of the IL-1 cytokine family. rIL-33 can promote production of Th2-type cytokines by Th2 cells and mast cells in vitro. Administration of rIL-33 to mice results in increases in IgE secretion and eosinophilic inflammation. However, the precise immune cell source of IL-33 remains unclear. Moreover, although recombinant pro-IL-33 is cleaved by recombinant caspase-1 in vitro, as are pro-IL-1beta and pro-IL-18, the involvement of caspase-1 in pro-IL-33 cleavage remains controversial. In this study, we show that mouse peritoneal macrophages, but not splenic dendritic cells, produced IL-33 upon stimulation with LPS. Likewise, mouse bone marrow cell-derived cultured mast cells also produced a small, but significant amount of IL-33 via FcepsilonRI cross-linking, but not in response to stimulation with LPS. To our surprise, IL-33 release was found even in caspase-1-deficient, caspase-8 inhibitor-treated, and calpain inhibitor-treated macrophages. These observations suggest that caspase-1-, caspase-8-, and calpain-independent IL-33 production by macrophages and/or mast cells may contribute to the pathogenesis of Th2-type allergic inflammation.

304: Evidence of the involvement of caspase-1 under physiologic and pathologic cellular stress during human pregnancy: A link between the inflammasome and parturition

304: Evidence of the involvement of caspase-1 under physiologic and pathologic cellular stress during human pregnancy: A link between the inflammasome and parturition

Caspase-1 activity is required for neuronal differentiation of PC12 cells: Cross-talk between the caspase and calpain systems

Previously, we have found that caspase-1 activity is increased during myoblast differentiation to myotubes. Here we show that caspase-1 activity is required for PC12 differentiation to neuronal-like cells. Caspase-1 is shown to be activated (by immunoblotting and by assessing activity in cell extracts) in the PC12 cells following the initial stage of differentiation. The inhibition of caspase-1 arrests PC12 cells at an intermediate stage of differentiation and prevents neurite outgrowth in these cells; the inhibition is reversed upon the removal of the inhibitor. Calpastatin (calpain endogenous specific inhibitor, and a known caspase substrate) is diminished at the later stages of PC12 cell differentiation, and diminution is prevented by caspase-1 inhibition. The degradation of fodrin (a known caspase and calpain substrate) is found in the advanced stage of differentiation. Caspase-1 has been implicated in the activation of proinflammatory cytokines, and in cell apoptosis. The involvement of caspase-1 in two distinct differentiation processes (myoblast fusion and neuronal differentiation of PC12 cells) indicates a function for this caspase in differentiation processes, and suggests some common mechanisms underlying caspase roles in such processes.

Caspase-1-induced calpastatin degradation in myoblast differentiation and fusion: cross-talk between the caspase and calpain systems

Previously, we found that calpastatin diminished transiently prior to myoblast fusion (rat L8 myoblasts), allowing calpain-induced protein degradation, required for fusion. Here we show that the transient diminution in calpastatin is due to its degradation by caspase-1. Inhibition of caspase-1 prevents calpastatin diminution and prevents myoblast fusion. Caspase-1 activity is transiently increased during myoblast differentiation. Both calpain and caspase appear to be responsible for the fusion-associated membrane protein degradation. Caspase-1 has been implicated in the activation of proinflammatory cytokines, and in cell apoptosis. The involvement of caspase-1 in L8 myoblast fusion represents a novel function for this caspase in a non-apoptotic differentiation process, and points to cross-talk between the calpain and caspase systems in some differentiation processes.

Photo-oxidative Stress Down-modulates the Activity of Nuclear Factor-κB via Involvement of Caspase-1, Leading to Apoptosis of Photoreceptor Cells

The mechanisms of photoreceptor cell death via apoptosis, in retinal dystrophies, are largely not understood. In the present report we show that visible light exposure of mouse cultured 661W photoreceptor cells at 4.5 milliwatt/cm2 caused a significant increase in oxidative damage of 661W cells, leading to apoptosis of these cells. These cells show constitutive expression of nuclear factor-kappaB (NF-kappaB), and light exposure of photoreceptor cells results in lowering of NF-kappaB levels in both the nuclear and cytosolic fractions in a time-dependent manner. Immunoblot analysis of IkappaBalpha and p50, and p65 (RelA) subunits of NF-kappaB, suggested that photo-oxidative stress results in their depletion. Immunocytochemical studies using antibody to RelA subunit of NF-kappaB further revealed the presence of this subunit constitutively both in the nucleus and cytoplasm of the 661W cells. Upon exposure to photo-oxidative stress, a depletion of the cytoplasmic and nuclear RelA subunit was observed. The depletion of NF-kappaB appears to be mediated through involvement of caspase-1. Furthermore, transfection of these cells with a dominant negative mutant IkappaBalpha greatly enhanced the kinetics of down modulation of NF-kappaB, resulting in a faster photo-oxidative stress-induced apoptosis. Taken together, these studies show that the presence of NF-kappaB RelA subunit in the nucleus is essential for protection of photoreceptor cells against apoptosis mediated by an oxidative pathway.

Involvement of Caspase-1 and Caspase-3 in the Production and Processing of Mature Human Interleukin 18 in Monocytic THP.1 Cells

Recently, human interleukin 18 (hIL-18) cDNA was cloned, and the recombinant protein with a tentatively assigned NH2-terminal amino acid sequence was generated. However, natural hIL-18 has not yet been isolated, and its cellular processing is therefore still unclear. To clarify this, we purified natural hIL-18 from the cytosolic extract of monocytic THP.1 cells. Natural hIL-18 exhibited a molecular mass of 18.2 kDa, and the NH2-terminal amino acid was Tyr37. Biological activities of the purified protein were identical to those of recombinant hIL-18 with respect to the enhancement of natural killer cell cytotoxicity and interferon-gamma production by human peripheral blood mononuclear cells. We also found two precursor hIL-18 (prohIL-18)-processing activities in the cytosol of THP.1 cells. These activities were blocked separately by the caspase inhibitors Ac-YVAD-CHO and Ac-DEVD-CHO. Further analyses of the partially purified enzymes revealed that one is caspase-1, which cleaves prohIL-18 at the Asp36-Tyr37 site to generate the mature hIL-18, and the other is caspase-3, which cleaves both precursor and mature hIL-18 at Asp71-Ser72 and Asp76-Asn77 to generate biologically inactive products. These results suggest that the production and processing of natural hIL-18 are regulated by two processing enzymes, caspase-1 and caspase-3, in THP.1 cells.