OBJECTIVE: By exposing mice carrying a deletion of NADPH oxidase isoform 4, NOX4, specifically in pancreatic β cells (βNOX4-/-) to nutrient excess stimulated by a high-fat diet (HFD), this study aimed to elucidate the role of β-cell redox status in the development of meta-inflammation within the diabetic phenotype. METHODS: The authors performed basic phenotyping of βNOX4-/- mice on HFD involving insulin and glycemic analyses, histochemistry of adipocytes, indirect calorimetry, and cytokine analyses. To characterize local inflammation, the study used caspase-1 activity assay, interleukin-1β immunochemistry, and real-time polymerase chain reaction during coculturing of β cells with macrophages. RESULTS: The phenotype of βNOX4-/- mice on HFD was not associated with hyperinsulinemia and hyperglycemia but showed accumulation of excessive lipids in epididymal fat and β cells. Surprisingly, mice showed significantly reduced systemic inflammation. Decreased interleukin-1β protein levels and downregulated NLRP3-inflammasome activity were observed on chronic glucose overload in βNOX4-/- isolated islets and NOX4-silenced INS1-E cells resulting in attenuated proinflammatory polarization of macrophages/monocytes in vitro and in situ and reduced local islet inflammation. CONCLUSIONS: Experimental evidence suggests that NOX4 pro-oxidant activity in β cells is involved in NLRP3-inflammasome activation during chronic nutrient overload and participates in local inflammatory signaling and perhaps toward peripheral tissues, contributing to a diabetic inflammatory phenotype.
Trimethylamine N-oxide (TMAO), a bioactive metabolite of gut microbes, plays a pivotal role in the pathogenesis of kidney diseases by activating programmed cell death (PCD) pathways. However, whether trimethylamine (TMA) contributes to chronic kidney injury and which kind of PCD is involved in TMA-induced chronic kidney injury has not been previously evaluated. To observe the effect of TMA, male C57BL/6J mice were randomly divided into two groups: the Control group and the TMA group. The mice in the TMA group were intraperitoneally injected with 100 micromol/kg/day TMA for three months, whereas the mice in the Control group were injected with normal saline for the same period. After three months, plasma creatinine and blood urea nitrogen levels, indicators of kidney function, increased significantly in the TMA group as compared with those in the Control group. Furthermore, Masson staining assay showed that TMA treatment led to a larger area of fibrosis than the Control group. TMA treatment did not change the Bax/Bcl-2 ratio, RIP1, RIP3 and MLKL phosphorylation, or iron and malondialdehyde levels in kidney tissues, indicating that apoptosis, ferroptosis and necroptosis were not involved in TMA-induced chronic kidney injury. However, compared with the Control group, TMA treatment significantly upregulated NLRP3, Caspase-1, IL-1beta, cleaved-Caspase 8, Caspase-8, and ZBP1 protein expression in kidney tissues. These results indicated that the ZBP1-NLRP3 inflammasome pathway was involved in TMA-induced chronic kidney injury. In conclusion, our studies revealed that the ZBP1-NLRP3 inflammasome may take part in the progression of TMA induced chronic kidney injury.
- MeSH
- chronická renální insuficience * metabolismus chemicky indukované patologie MeSH
- inflamasomy * metabolismus MeSH
- ledviny metabolismus účinky léků patologie MeSH
- methylaminy * metabolismus MeSH
- myši inbrední C57BL * MeSH
- myši MeSH
- protein NLRP3 * metabolismus MeSH
- signální transdukce * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Lipidome perturbation occurring during meta-inflammation is associated to left ventricle (LV) remodeling though the activation of the NLRP3 inflammasome, a key regulator of chronic inflammation in obesity-related disorders. Little is known about phosphatidylcholine (PC) and phosphatidylethanolamine (PE) as DAMP-induced NLRP3 inflammasome. Our study is aimed to evaluate if a systemic reduction of PC/PE molar ratio can affect NLRP3 plasma levels in cardiovascular disease (CVD) patients with insulin resistance (IR) risk. Forty patients from IRCCS Policlinico San Donato were enrolled, and their blood samples were drawn before heart surgery. LV geometry measurements were evaluated by echocardiography and clinical data associated to IR risk were collected. PC and PE were quantified by ESI-MS/MS. Circulating NLRP3 was quantified by an ELISA assay. Our results have shown that CVD patients with IR risk presented systemic lipid impairment of PC and PE species and their ratio in plasma was inversely associated to NLRP3 levels. Interestingly, CVD patients with IR risk presented LV changes directly associated to increased levels of NLRP3 and a decrease in PC/PE ratio in plasma, highlighting the systemic effect of meta-inflammation in cardiac response. In summary, PC and PE can be considered bioactive mediators associated to both the NLRP3 and LV changes in CVD patients with IR risk.
- MeSH
- fosfatidylcholiny * krev MeSH
- fosfatidylethanolaminy * krev metabolismus MeSH
- inflamasomy * metabolismus MeSH
- inzulinová rezistence * MeSH
- kardiovaskulární nemoci * krev patologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- protein NLRP3 * metabolismus MeSH
- remodelace komor * MeSH
- senioři MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Pyroptosis is a form of cell death associated with inflammation. In the maintenance of airway homeostasis, pyroptosis goes through activation and assembly of Inflammasome. The pyroptosis pathway is mediated by caspase which activates the pore-forming effect of substrate gasdermin family members. It eventually leads to lysis and release of the cell contents and then induces an inflammatory response. In this process, it participates in airway homeostasis regulation by affecting airway immunity, airway epithelial structure and airway microbiota. Therefore, we discussed the correlation between airway immunity, airway epithelial structure, airway microbiota and the mechanism of pyroptosis to describe the role of pyroptosis in airway homeostasis regulation which is of great significance for understanding the occurrence and treatment of airway inflammatory diseases.
- MeSH
- homeostáza MeSH
- inflamasomy * metabolismus MeSH
- kaspasy metabolismus MeSH
- lidé MeSH
- pyroptóza * fyziologie MeSH
- zánět MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Apolipoprotein J (clusterin) is a component of high-density lipoproteins, the high level of which is reversely correlated with the risk of coronary heart disease. In addition, it exerts anti-inflammatory and anti-apoptotic effects on endothelial cells and inhibits smooth muscle cell migration and proliferation, indicating that it may play a protective role in cardiovascular disease. However, the exact mechanisms by which this occurs remain unclear. This study aimed to clarify these underlying protective mechanisms by researching the inhibitory effects of apolipoprotein J via the NOD-like receptor protein 3 pathway on the inflammation induced by cholesterol crystals in THP‐1 macrophages. In culture, THP-1 macrophages were infected with adenoviral vectors containing apolipoprotein J genes and subsequently treated with cholesterol crystals. The inflammatory cytokines interleukin‐1β, interleukin 18 and tumour necrosis factor α were quantitatively measured with ELISA kits. NOD-like receptor protein 3, cysteinyl aspartate specific proteinase 1 and interleukin 1β were evaluated by Western blot and PCR analysis. As a result, apolipoprotein J expression was found to remarkably decrease the levels of inflammatory cytokines, including tumour necrosis factor α, interleukin 18 and interleukin 1β, secreted by THP‐1 macrophages. It was also found capable of inhibiting the levels of NOD-like receptor protein 3, cysteinyl aspartate-specific proteinase 1 and interleukin 1β both at the protein and mRNA levels. In the current study, we revealed that over-expression of apolipoprotein J attenuated the inflammation induced by cholesterol crystals through inhibition of the NOD-like receptor protein 3 inflammasome pathway.
- MeSH
- cholesterol metabolismus MeSH
- cytokiny metabolismus MeSH
- endoteliální buňky metabolismus patologie MeSH
- inflamasomy * metabolismus farmakologie MeSH
- interleukin-18 metabolismus MeSH
- interleukin-1beta metabolismus MeSH
- klusterin metabolismus farmakologie MeSH
- kyselina asparagová metabolismus farmakologie MeSH
- lidé MeSH
- makrofágy metabolismus MeSH
- proteasy metabolismus farmakologie MeSH
- protein NLRP3 * metabolismus MeSH
- TNF-alfa metabolismus MeSH
- zánět patologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Nanodiamonds (ND), especially fluorescent NDs, represent potentially applicable drug and probe carriers for in vitro/in vivo applications. The main purpose of this study was to relate physical-chemical properties of carboxylated NDs to their intracellular distribution and impact on membranes and cell immunity-activation of inflammasome in the in vitro THP-1 cell line model. Dynamic light scattering, nanoparticle tracking analysis, and microscopic methods were used to characterize ND particles and their intracellular distribution. Fluorescent NDs penetrated the cell membranes by both macropinocytosis and mechanical cutting through cell membranes. We proved accumulation of fluorescent NDs in lysosomes. In this case, lysosomes were destabilized and cathepsin B was released into the cytoplasm and triggered pathways leading to activation of inflammasome NLRP3, as detected in THP-1 cells. Activation of inflammasome by NDs represents an important event that could underlie the described toxicological effects in vivo induced by NDs. According to our knowledge, this is the first in vitro study demonstrating direct activation of inflammasome by NDs. These findings are important for understanding the mechanism(s) of action of ND complexes and explain the ambiguity of the existing toxicological data.
- MeSH
- buněčná membrána účinky léků metabolismus ultrastruktura MeSH
- dynamický rozptyl světla MeSH
- elektronová mikroskopie MeSH
- fluorescence MeSH
- inflamasomy účinky léků imunologie metabolismus MeSH
- intravitální mikroskopie metody MeSH
- kathepsin B imunologie metabolismus MeSH
- konfokální mikroskopie MeSH
- lidé MeSH
- lyzozomy účinky léků imunologie metabolismus ultrastruktura MeSH
- mikroskopie atomárních sil MeSH
- nanodiamanty aplikace a dávkování chemie MeSH
- pinocytóza MeSH
- protein NLRP3 imunologie metabolismus MeSH
- THP-1 buňky MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Intracelulární parazitismus je fenomén, který se v přírodě vyskytuje již více než miliardu let. Jeho podstatou je schopnost virů a některých bakterií přežívat uvnitř eukaryotické hostitelské buňky a navíc parazitovat na jejím metabolickém aparátu. Podle klasické definice se mezi intracelulárně parazitické bakterie řadí pouze ty taxony, které jsou schopny přežívat uvnitř makrofágů, nicméně schopnost bakterii přežívat uvnitř dalších typů eukaryotických buněk je v přírodě, jak se ukázalo později, daleko rozšířenějším jevem. Reakce makrofágů na invadujicí mikroby je klíčovým momentem rezistence celého hostitelského organizmu a na její rychlosti a efektivitě závisi jeho další osud. Pokud by například bez zásahu přirozené imunity v organizmu volně přežíval 24 hodin patogen s průměrným zdvojovacim časem 20 min., pak by byl hostitel zaplaven více než 2 x 10²´ bakteriemi, což je neslučitelné se životem. V následujícím textu jsou shrnuty základní momenty v procesu indukce efektivní odpovědi makrofágů zejména ve smyslu jejich protektivity vůči intracelulárním parazitům. Zároveň jsou shrnuty některé obranné mechanizmy bakterií a možnosti klinického využití detekce funkčního stavu buněk přirozené imunity.
Intracellular parasitism is a phenomenon present in nature for more than one billion years. Its keystone is the intriguing ability of viruses and some bacteria to survive and multiply inside eukaryotic host cells and to parasitize on their metabolic machinery. According to the classical definition, germs are classified as intracellular parasites only if they are able to survive inside macrophages. However, the ability of germs to survive inside eukaryotic cells is much more common than it was expected earlier. Reaction of macrophages to invading microbes is the key point in the complex immunological resistance of the host. The outcome of the host is substantially linked to macrophage reactivity. For example, if an evading microbe with a replication time of 20 minutes survived inside a host for 24 hours without reaction of innate immunity, there would be more than 2 x lO²´ microbes at the end of this period. It would be fatal for the host, indeed. The key activities of macrophages in the sense of protection against intracellular parasites are reviewed. Some mechanisms of microbial defence and some new approaches to clinical diagnosis of the functional status of cells of innate immunity are also discussed.
- Klíčová slova
- aktivace, obranné mechanizmy bakterií,
- MeSH
- aktivace makrofágů MeSH
- fyzikální stimulace MeSH
- inflamasomy metabolismus MeSH
- interakce hostitele a patogenu MeSH
- interferon gama metabolismus MeSH
- lidé MeSH
- lipopolysacharidy farmakologie MeSH
- makrofágy imunologie mikrobiologie MeSH
- MAP kinasový signální systém MeSH
- NF-kappa B metabolismus MeSH
- přirozená imunita MeSH
- signální transdukce MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
