mRNA Expression Of Inflammasome Components Research Articles

Transcriptomics and experimental validation-based approach to understand the effect and mechanism of Huangqin tang interfeience with colitis associated colorectal cancer

ContextChronic inflammation is usually caused by persistent irritation or uncontrolled infection and is characterized by ongoing tissue damage, injury-induced cellular proliferation and tissue repair. Colitis-associated colorectal cancer (CAC) isone of the classic examples of tumors that are tightly related to chronic inflammation. BackgroundTo investigated the key pharmacodynamic genes of HQT interventions in CAC by using transcriptome predictions and experiments.Materials & Methods: We used the azoxymethane/dextran sodium sulfate method to induce the mice CAC model. After preventive administration of HQT to the mice model, colonic tissues were taken for transcriptome sequencing and the transcriptome results were then experimentally validated using quantitative Real-Time PCR technique. ResultsTranscriptome sequencing revealed that the effect of the mechanism of HQT on the CAC mice model maybe related to its inhibition of accelerated epithelial mesenchymal transition and induction of pyroptosis. The levels of Matrix-metalloproteinases such as MMP-2, MMP-9 were significantly reduced in CAC mice treated with HQT; The mRNA expression for Krt17, App, CD44 and WNT pathway related sites such as Lrrc15, Cldn-1, Mpc1, Agr2 which are related factors affecting the epithelial mesenchymal transition were significantly reduced in CAC mice treated with HQT; the aberrant mRNA expression of inflammasome components that drive pyroptosis, including Nlrp3, Caspase-1, ASC, GSDMD and its mediated product IL-18 have been improved. ConclusionsOur findings provide preliminary clarification that inhibiting the progression of CAC by using HQT is effective, the mechanism of action may be relatedto the inhibition of epithelial mesenchymal transition and induction of pyroptosis during tumorigenesis.

PS-B06-7: ENDOTHELIAL DYSFUNCTION EXACERBATES KIDNEY DYSFUNCTION IN AGEING KIDNEY VIA ACTIVATION OF INFLAMMASOME

Background: Ageing affects the function of the immune system and leads to immunosenescence, which is characterized by defective immune responses and increased systemic inflammation (also termed inflammageing). Inflammageing is maladaptive and results from multiple mechanisms, including aberrant inflammasome activation. The ASC is an essential component of inflammasomes that activates caspase 1. Endothelial dysfunction is also a common pathophysiologic mechanism of age-related organ damage. Nitric oxide (NO) produced by endothelial nitric oxide synthase (eNOS) is an important mediator in the maintenance of vascular homeostasis. We have reported that the eNOS-NO pathway attenuates the progression of kidney injury via suppression of inflammasomes. However, the relationship between the eNOS-NO pathway and inflammageing in the kidney remains unclear. To determine if the eNOS-NO pathway attenuates kidney damage via the regulation of inflammasome activation in ageing kidneys, we used eNOS-deficient mice (eNOSKO) and eNOS-ASC double-knockout mice (eNOS-ASC-DKO). Methods: Wild-type mice (WT) and eNOSKO were used to determine the role of the eNOS-NO pathway in ageing kidneys. WT and eNOSKO were sacrificed at 18 months of age to harvest kidney tissue. The localization of inflammasome activation in the kidney was evaluated with immunohistochemical analyses. To determine the role of inflammasomes in ageing kidneys, we generated eNOS-ASC-DKO. The mRNA expression of inflammasome components were determined in isolated glomeruli. Results: The glomerular injury was more exacerbated in eNOSKO-18 M than in WT-18 M. In the immunohistochemical analyses, the expression of ASC coexisted with the macrophages detected by F4/80 staining in eNOSKO-18 M. These data suggested that the inflammasome activation was located in the macrophages. In the isolated glomeruli, the mRNA of the inflammasome components was higher in eNOSKO-18 M than in WT-18 M. The glomerular damage and tubulointerstitial damage were ameliorated in eNOS-ASC-DKO-18 M compared to eNOSKO-18 M. In summary, in eNOS-deficient mice, inflammasomes were activated in macrophages, and interstitial fibrosis was exacerbated. However, in eNOS-ASC-DKO-18 M mice, the tubulointerstitial damage was attenuated. Conclusion: Endothelial NOS/NO signaling ameliorates kidney damage in the aging process via the modulation of inflammageing associated with inflammasome-activation.

RIPK3 blockade attenuates tubulointerstitial fibrosis in a mouse model of diabetic nephropathy

Receptor-interacting protein kinase-3 (RIPK3) is a multifunctional regulator of cell death and inflammation. RIPK3 controls cellular signalling through the formation of the domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, which is recognised to mediate renal fibrogenesis. The role of RIPK3 in diabetic kidney disease (DKD) induced renal fibrosis has not been previously determined. To define the action of RIPK3 in the development of diabetic kidney disease, wild-type (WT), RIPK3 -/- and endothelium-derived nitric oxide synthase (eNOS)-/- mice were induced to develop diabetes mellitus using multiple low doses of streptozotocin and maintained for 24 weeks. RIPK3 activity and NLRP3 expression were upregulated and fibrotic responses were increased in the kidney cortex of WT mice with established diabetic nephropathy compared to control mice. Consistently, mRNA expression of inflammasome components, as well as transforming growth factor beta 1 (TGFβ1), α smooth muscle actin (α-SMA) and collagen deposition were increased in diabetic kidneys of WT mice compared to control mice. However, these markers were normalised or significantly reversed in kidneys of diabetic RIPK3 -/- mice. Renoprotection was also observed using the RIPK3 inhibitor dabrafenib in eNOS-/- diabetic mice as demonstrated by reduced collagen deposition and myofibroblast activation. These results suggest that RIPK3 is associated with the development of renal fibrosis in DKD due to the activation of the NLRP3 inflammasome. Inhibition of RIPK3 results in renoprotection. Thus, RIPK3 may be a potential target for therapeutic intervention in patients with diabetic kidney disease.

Characterization of Inflammasome Components in Pig Intestine and Analysis of the Influence of Probiotic Enterococcus Faecium during an Escherichia Coli Challenge

ABSTRACTThe aim of the present study was to investigate systematically the expression of inflammasome components in pig intestine and to analyze the influence of age and long-term supplementation with the probiotic Enterococcus faecium NCIMB 10415 (E. faecium). In order to examine probiotic effects on the inflammasomes during a challenge with pathogens, enterotoxigenic Escherichia coli (ETEC) and E. faecium were directly added to pig jejunum in Ussing chambers.The mRNA expression of inflammasome components generally decreased in an oral-aboral direction in intestinal tissues. In 29-day-old piglets, the expression levels of NLRP3 were significantly higher and ASC (apoptotic speck-like protein containing a caspase recruitment domain) expression were lower compared with those in the ileum of 70-day-old pigs (p ≤ 0.05). Long-term supplementation with E. faecium significantly increased ASC expression levels in the jejunum and ileum of 29-day-old piglets compared to control animals (p ≤ 0.05). Ex vivo addition of ETEC or E. faecium did not affect mRNA expression of inflammasome components significantly, whereas IL-1β protein release was significantly elevated in ETEC-incubated jejunum (p ≤ 0.05), providing evidence for the functional activation of the inflammasome, which was prevented by pre-incubation with E. faecium.We conclude that pre-incubation with E. faecium has a protective effect during ETEC challenge; this effect is probably not located at the inflammasome transcription level. The results of this study of the expression and regulation of inflammasome components in pigs are similar to those obtained in humans, reinforcing the use of pigs as a suitable model for translational inflammasome research.

SRT1720, a sirtuin 1 activator, attenuates organ injury and inflammation in sepsis

BackgroundSepsis affects 800,000 patients in the United States annually with a mortality rate of up to 30%. Recent studies suggest that sepsis-associated metabolic derangements due to hypoxic tissue injury, impaired oxygen utilization, and mitochondrial dysfunction contribute to mortality. Sirtuin 1 (Sirt1) is a crucial modulator of energy metabolism during starvation states and has anti-inflammatory effects. Here, we hypothesized that SRT1720, a Sirt1 activator, could attenuate the severity of sepsis. Materials and methodsMale C57BL/6 mice (20-25 g) were subjected to cecal ligation and puncture (CLP) to induce sepsis. SRT1720 (5 or 20 mg/kg BW) or 10% dimethyl sulfoxide (vehicle) in 0.2-mL saline was injected intravenously at 5 h after CLP. Control animals were not subjected to any surgery. Blood and liver samples were harvested at 20 h after CLP for analysis. ResultsAdministration of SRT1720 markedly reduced the serum levels of tissue injury markers (aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase) and renal injury markers (blood urea nitrogen and creatinine) in a dose-dependent manner after CLP. Furthermore, the levels of proinflammatory cytokines interleukin (IL)-1β and IL-6 in the serum and liver were significantly inhibited by SRT1720 treatment after CLP. SRT1720 treatment resulted in a significantly decreased mRNA expression of inflammasome components (nucleotide oligomerization domain–like receptor protein 3, adapter apoptosis-associated speck-like protein containing caspase-recruitment domain, IL-1β, and IL-18) in the liver, compared with the vehicle group. ConclusionsSRT1720 treatment attenuates multiorgan injury in septic mice. SRT1720 treatment also decreases the production of proinflammatory cytokines and reduces inflammasome activation. Thus, pharmacologic stimulation of Sirt1 may present a promising therapeutic strategy for sepsis.

Beneficial Effect of Fish Oil on Liver Steatosis: Involvement of Kupffer Cell polarization and Inflammasome Inactivation

Background Beneficial effect of marine derived fish oil on liver steatosis has been reported. Recently, a G protein-coupled receptor, FFA4 (aka GPR120) has been elucidated as an omega-3 fatty acid-sensing receptor. FFA4 expression in Kupffer cells and hepatocytes was reported. We investigated effect of polyunsaturated fatty acids on alcoholic fatty liver disease. As a mechanism study, we conducted experiments on inflammasome activation and Kupffer cell polarization. METHODS: Female C57/BL6 mouse were fed an ethanol or control-liquid diet with fish oil polyunsaturated fatty acids or saturated fatty acids for 2 weeks. Plasma transaminase, triglyceride levels, and liver histology were evaluated. Polarization of Kupffer cells and inflammasome activation were investigated by RT-PCR and Western analysis. RESULTS: First we confirmed FFA4 expression in Kupffer cells and hepatocytes. Liver steatosis induced by ethanol-liquid diet was deminished in mouse fed the ethanol plus fish oil diet but not corn oil diet. Fish oil supplementation also decreased plasma transaminase and triglyceride levels. Furthermore, ethanol drinking induced M1 polarization of Kupffer cells. However, fish oil administration polarized Kupffer cells into M2 phenotype. In addition mRNA expression of inflammasome components, such as NLRP3, ASC, and caspase-1 were decreased by fish oil supplementation, which led to reduced IL-1β production. SUMMARY: Supplementation of fish oil alleviated fat accumulation in a mouse model of alcoholic fatty liver disease. Fish oil inducing M2 polarization of Kupffer cells and inhibiting inflammasome activation were involved in anti-inflammatory and anti-steatosis effects of fish oil.