scholarly journals 3β,23-Dihydroxy-12-ene-28-ursolic Acid Isolated from Cyclocarya paliurus Alleviates NLRP3 Inflammasome-Mediated Gout via PI3K-AKT-mTOR-Dependent Autophagy

2022 ◽  
Vol 2022 ◽  
pp. 1-15
Author(s):  
Dongxiao Lou ◽  
Xiaogai Zhang ◽  
Cuihua Jiang ◽  
Fang Zhang ◽  
Chao Xu ◽  
...  
Keyword(s):  
Protein Expression ◽  
Ursolic Acid ◽  
Nlrp3 Inflammasome ◽  
Soft Tissues ◽  
Underlying Mechanism ◽  
Inhibitory Effect ◽  
Expression Level ◽  
Expression Ratio ◽  
Cyclocarya Paliurus ◽  
Caspase 1

Gout is regarded as a painful inflammatory arthritis induced by the deposition of monosodium urate crystals in joints and soft tissues. Nucleotide-binding oligomerization domain (NOD)-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome-mediated IL-1β production plays a crucial role in the pathological process of gout. Cyclocarya paliurus (CP) tea was found to have an effect on reducing the blood uric acid level of people with hyperuricemia and gout. However, its medicinal ingredients and mechanism for the treatment of gout are still unclear. Thus, this study was designed to investigate the effects of the active triterpenoids isolated from C. paliurus on gout and explore the underlying mechanism. The results showed that compound 2 (3β,23-dihydroxy-12-ene-28-ursolic acid) from C. paliurus significantly decreased the protein expression of IL-1β, caspase-1, pro-IL-1β, pro-caspase-1, and NLRP3. Furthermore, the production of ROS in the intracellular was reduced after compound 2 treatment. However, ROS agonist rotenone remarkably reversed the inhibitory effect of compound 2 on the protein expression of NLRP3 inflammasome. Additionally, the expression level of LC3 and the ratio of LC3II/LC3I were increased, but the expression level of p62 was suppressed by compound 2 whereas an autophagy inhibitor 3-methyladenine (3-MA) significantly abolished the inhibitory effects of compound 2 on the generation of ROS and the protein expression of NLRP3 inflammasome. Moreover, compound 2 could ameliorate the expression ratio of p-PI3K/PI3K, p-AKT/AKT, and p-mTOR/mTOR. Interestingly, mTOR activator MHY-1485 could block the promotion effect of compound 2 on autophagy regulation and inhibitory effect of compound 2 on induction of ROS and IL-1β. In conclusion, these findings suggested that compound 2 may effectively improve NLRP3 inflammasome-mediated gout via PI3K-AKT-mTOR-dependent autophagy and could be further investigated as a potential agent against gout.

scholarly journals Selenium ameliorates S. aureus-induced inflammation through ROS-mediated NLRP3 inflammasome in bovine mammary epithelial cells

2020 ◽  
Author(s):  
Chongliang Bi ◽  
Shujiu Zhang ◽  
He Tang ◽  
Hui Li
Keyword(s):  
Protein Expression ◽  
Nlrp3 Inflammasome ◽  
Mammary Epithelial Cells ◽  
Mammary Epithelial ◽  
Expression Level ◽  
Bovine Mammary Epithelial Cells ◽  
Caspase 1 ◽  
Through Flow ◽  
Anti Inflammatory ◽  
Inflammatory Effect

Abstract Background Some research has indicated that selenium (Se) plays a significant role during mastitis. However the intracellular anti-inflammatory effect of Se is not fully clear. Due to the ability of Staphylococcus aureus ( S. aureus ) to internalize into host cell, in this study we explored whether Se could regulate inflammation induced by S. aureus through reactive oxygen species (ROS)-mediated NLRP3 inflammasome in bMECs. Result bMECs were treated with 8 μmol/L Na 2 SeO 3 for 12 h before infected with S. aureus for 2 h. Through flow cytometry, Western blot and qPCR analysis, ROS and NLRP3 imflammasome were detected. Result shown that the production of ROS was increased by S. aureus , Se exerted strong inhibitory effects on the production of ROS; The protein expression of NLRP3 inflammasome including NLRP3, ASC and Caspase-1 increased significantly after S. aureus infection, Se played an important role in regulating the expression of NLRP3, ASC and Caspase-1; To further investigate the anti-inflammatory effect of Se, the expression level of IL-1β associated molecule pro-IL-1β and IL-1β were detected. Result shown that the mRNA expression of IL-1β was up-regulated by S. aureus and after Se treatment the expression level of IL-1β mRNA was markedly down-regulated, meanwhile Se play a regulation effect on the protein expression of Pro-IL-1β and IL-1β. Conclusions Here we show that ROS is involved in bMECs inflammation induced by S. aureus and Se ameliorates S. aureus -induced inflammation through ROS-mediated NLRP3 pathway in bMECs.

scholarly journals Toll-Like Receptor 2 and NLRP3 Cooperate To Recognize a Functional Bacterial Amyloid, Curli

2014 ◽  
Vol 83 (2) ◽  
pp. 693-701 ◽  
Author(s):  
Glenn J. Rapsinski ◽  
Meghan A. Wynosky-Dolfi ◽  
Gertrude O. Oppong ◽  
Sarah A. Tursi ◽  
R. Paul Wilson ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Nlrp3 Inflammasome ◽  
Amyloid Β ◽  
Underlying Mechanism ◽  
Secondary Amyloidosis ◽  
Toll Like Receptor ◽  
Content Type ◽  
Caspase 1 ◽  
Toll Like Receptor 2

Amyloids are proteins with cross-β-sheet structure that contribute to pathology and inflammation in complex human diseases, including Alzheimer's disease, Parkinson's disease, type II diabetes, and secondary amyloidosis. Bacteria also produce amyloids as a component of their extracellular matrix during biofilm formation. Recently, several human amyloids were shown to activate the NLRP3 inflammasome, leading to the activation of caspase 1 and production of interleukin 1β (IL-1β). In this study, we investigated the activation of the NLRP3 inflammasome by bacterial amyloids using curli fibers, produced bySalmonella entericaserovar Typhimurium andEscherichia coli. Here, we show that curli fibers activate the NLRP3 inflammasome, leading to the production of IL-1β via caspase 1 activation. Investigation of the underlying mechanism revealed that activation of Toll-like receptor 2 (TLR2) by curli fibers is critical in the generation of IL-1β. Interestingly, activation of the NLRP3 inflammasome by curli fibers or by amyloid β of Alzheimer's disease does not cause cell death in macrophages. Overall, these data identify a cross talk between TLR2 and NLRP3 in response to the bacterial amyloid curli and generation of IL-1β as a product of this interaction.

Mesoporous silica nanoparticles induced hepatotoxicity via NLRP3 inflammasome activation and caspase-1-dependent pyroptosis

Nanoscale ◽  
2018 ◽  
Vol 10 (19) ◽  
pp. 9141-9152 ◽  
Author(s):  
Xuyao Zhang ◽  
Jingyun Luan ◽  
Wei Chen ◽  
Jiajun Fan ◽  
Yanyang Nan ◽  
...  
Keyword(s):  
Mesoporous Silica ◽  
Silica Nanoparticles ◽  
Nlrp3 Inflammasome ◽  
Mesoporous Silica Nanoparticles ◽  
Silica Nanoparticle ◽  
Underlying Mechanism ◽  
Inflammasome Activation ◽  
Mesoporous Silica Nanoparticle ◽  
Caspase 1 ◽  
Nlrp3 Inflammasome Activation

Novel insights into mesoporous silica nanoparticle (MSN)-induced hepatotoxicity and the underlying mechanism, facilitating an increase of the biosafety of MSNs.

Dual Targeting of Autophagy and NF-κB Pathway by PPARγ Contributes to the Inhibitory Effect of Demethoxycurcumin on NLRP3 Inflammasome Priming

2021 ◽  
Vol 14 ◽  
Author(s):  
Jing Tang ◽  
Xiaoxue Tan ◽  
Xiangmi Huang ◽  
Jie Zhang ◽  
Liang Chen ◽  
...  
Keyword(s):  
Nlrp3 Inflammasome ◽  
Nuclear Translocation ◽  
Inhibitory Effect ◽  
Caspase 1 ◽  
Dual Targeting ◽  
Transmission Electron ◽  
Subsequent Activation ◽  
Natural Derivative ◽  
Pparγ Expression

Background: Demethoxycurcumin (DMC), a natural derivative of curcumin, has anti-inflammatory activities. However, the mechanism has not been fully elucidated. Objective: The aim of the current study was to investigate the role of DMC on NLRP3 inflammasome priming. Methods: Protein expression was quantified by western blotting. Inflammatory cytokines were measured by ELISA. Autophagosomes were evaluated by transmission electron microscopy. Results: DMC inhibited LPS-stimulated NLRP3, pro-caspase-1, and pro-IL-1β expression. Meanwhile, DMC diminished NLRP3-dependent IL-1β maturation, caspase-1 activation, IL-1β and IL-18 production caused by LPS plus ATP. Moreover, DMC induced autophagy and autophagy inhibitor 3-MA abrogated the role of DMC on NLRP3 inflammasome priming and subsequent activation. DMC also inhibited LPS-stimulated phosphorylation and nuclear translocation of p65 NF-κB. Additionally, DMC significantly increased the PPARγ expression and the effects of DMC in NF-κB inhibition, autophagy, and NLRP3 inflammasome priming were abrogated by specific PPARγ antagonist T0070907. Conclusion: The evidence presented here has confirmed that DMC increases PPARγ expression, resulting in autophagy and NF-κB inhibition, and subsequently inhibits LPS-induced NLRP3 inflammasome priming and subsequent activation.

scholarly journals Artificially Cultivated Ophiocordyceps sinensis Alleviates Diabetic Nephropathy and Its Podocyte Injury via Inhibiting P2X7R Expression and NLRP3 Inflammasome Activation

2018 ◽  
Vol 2018 ◽  
pp. 1-16 ◽  
Author(s):  
Chao Wang ◽  
Xiao-xia Hou ◽  
Hong-liang Rui ◽  
Li-jing Li ◽  
Jing Zhao ◽  
...  
Keyword(s):  
Diabetic Nephropathy ◽  
Protein Expression ◽  
Nlrp3 Inflammasome ◽  
Kidney Tissue ◽  
Therapeutic Effects ◽  
Low Grade ◽  
Podocyte Injury ◽  
Ophiocordyceps Sinensis ◽  
Caspase 1 ◽  
Mrna And Protein Expression

Background/Aims. It is known that chronic low-grade inflammation contributes to the initiation and development of both diabetes and diabetic nephropathy (DN), so we designed this study to investigate the role of P2X7R and NLRP3 inflammasome in DN pathogenesis and the antagonistic effects of artificially cultivated Ophiocordyceps sinensis (ACOS). Methods. A rat model of DN caused by high-fat-diet feeding and low-dose streptozotocin injection and a mouse podocyte injury model induced by high-glucose (HG) stimulation were established, and the intervention effects of ACOS on them were observed. The biological parameters of serum and urine and the pathological manifestations of kidney tissue were examined. The expression of mRNA and protein of P2X7R and NLRP3 inflammasome (NLRP3, ASC, and caspase-1) and downstream effectors (IL-1β and IL-18), as well as podocyte-associated molecules, was determined by real-time quantitative PCR and Western blot assay, respectively. Results. The DN rats showed to have developed insulin resistance, elevated fasting blood glucose, increased urinary protein excretion, and serum creatinine level as well as corresponding glomerular pathological alterations including podocyte damages. ACOS significantly antagonized the above changes. The experiments in vivo and in vitro both displayed that the mRNA and protein expression of P2X7R, NLRP3, ASC, caspase1 (procaspase-1 mRNA in the gene level and active caspase-1 subunit P10 in the protein level), IL-1β, and IL-18 was significantly upregulated and the mRNA and protein expression of podocyte-associated molecules was significantly changed (downregulation of nephrin, podocin, and WT-1 expression and upregulation of desmin expression) indicating podocyte injury in the kidney tissue of DN rats and in the HG-stressed mouse podocytes, respectively. ACOS also significantly antagonized all the above changes. Conclusion. Our research work suggests that P2X7R and NLRP3 inflammasome are involved in the pathogenesis of DN, and ACOS can effectively inhibit the high expression of P2X7R and the activation of NLRP3 inflammasome, which may contribute to the therapeutic effects of Ophiocordyceps sinensis.

scholarly journals Role of ASM/Cer/TXNIP signaling module in the NLRP3 inflammasome activation

2020 ◽  
Author(s):  
Jianjun Jiang ◽  
Jin Yang ◽  
Yining Shi ◽  
Jiyu Cao ◽  
Youjin Lu ◽  
...  
Keyword(s):  
Nlrp3 Inflammasome ◽  
Underlying Mechanism ◽  
Acid Sphingomyelinase ◽  
Receptor Protein ◽  
Inflammasome Activation ◽  
Mrna Levels ◽  
Caspase 1 ◽  
Nlrp3 Inflammasome Activation

Abstract Background: The NOD-Like Receptor Protein 3 (NLRP3) inflammasome is a crucial component of an array of inflammatory conditions. It functions by boosting the secretion of pro-inflammatory cytokines: interleukin-1β (IL-1β) and interleukin-18 (IL-18). Previous studies have established the vital role of the acid sphingomyelinase (ASM)/ceramide (Cer) pathway in the functional outcome of cells, with a particular emphasis on the inflammatory processes. This study aimed to explore the effects and associated underlying mechanism of Cer-induced NLRP3 inflammasome activation.Methods: Lipopolysaccharide (LPS)/adenosine triphosphate (ATP)-induced NLRP3 inflammasome activation in J774A.1 cells was used as an in vitro inflammatory model. Western blotting and Real-time PCR (RT-PCR) were used to detect the protein and mRNA levels, respectively. IL-1β and IL-18 levels were evaluated using ELISA kits. ASM assay kit and immunofluorescence were used to detect ASM activity and Cer content.Results: Imipramine, a well-known inhibitor of ASM, significantly inhibited ASM activity and inhibited Cer accumulation, which indicated ASM activation. Besides, it also suppressed the LPS/ATP-induced expression of proteins and mRNA: thioredoxin interacting protein (TXNIP), NLRP3, caspase-1, IL-1β and IL-18. Interestingly verapamil, a TXNIP inhibitor, suppressed LPS/ATP-induced TXNIP/NLRP3 inflammasome activation; however, it did not affect LPS/ATP-induced ASM activation and ceramide production. Further analysis showed that the exogenous C2-Cer treated J774A.1 cells induced the overexpression of TXNIP, NLRP3, caspase-1, IL-1β and IL-18. Besides, TXNIP siRNA or verapamil inhibited C2-Cer-induced TXNIP overexpression and NLRP3 inflammasome activation.Conclusion: This study demonstrated the involvement of the ASM/Cer/TXNIP signaling pathway in NLRP3 inflammasome activation.

scholarly journals Carbon monoxide negatively regulates NLRP3 inflammasome activation in macrophages

2015 ◽  
Vol 308 (10) ◽  
pp. L1058-L1067 ◽  
Author(s):  
Sung-Soo Jung ◽  
Jong-Seok Moon ◽  
Jin-Fu Xu ◽  
Emeka Ifedigbo ◽  
Stefan W. Ryter ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Nlrp3 Inflammasome ◽  
Inflammatory Diseases ◽  
Protein Complexes ◽  
Inhibitory Effect ◽  
Negative Regulator ◽  
Ros Generation ◽  
Inflammasome Activation ◽  
Caspase 1 ◽  
Nlrp3 Inflammasome Activation

Inflammasomes are cytosolic protein complexes that promote the cleavage of caspase-1, which leads to the maturation and secretion of proinflammatory cytokines, including interleukin-1β (IL-1β) and IL-18. Among the known inflammasomes, the nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3)-dependent inflammasome is critically involved in the pathogenesis of various acute or chronic inflammatory diseases. Carbon monoxide (CO), a gaseous molecule physiologically produced in cells and tissues during heme catabolism, can act as an anti-inflammatory molecule and a potent negative regulator of Toll-like receptor signaling pathways. To date, the role of CO in inflammasome-mediated immune responses has not been fully investigated. Here, we demonstrated that CO inhibited caspase-1 activation and the secretion of IL-1β and IL-18 in response to lipopolysaccharide (LPS) and ATP treatment in bone marrow-derived macrophages. CO also inhibited IL-18 secretion in response to LPS and nigericin treatment, another NLRP3 inflammasome activation model. In contrast, CO did not suppress IL-18 secretion in response to LPS and poly(dA:dT), an absent in melanoma 2 (AIM2)-mediated inflammasome model. LPS and ATP stimulation induced the formation of complexes between NLRP3 and apoptosis-associated speck-like protein, or NLRP3 and caspase-1. CO treatment inhibited these molecular interactions that were induced by LPS and ATP. Furthermore, CO inhibited mitochondrial ROS generation and the decrease of mitochondrial membrane potential induced by LPS and ATP in macrophages. We also observed that the inhibitory effect of CO on the translocation of mitochondrial DNA into the cytosol was associated with suppression of cytokine secretion. Our results suggest that CO negatively regulates NLRP3 inflammasome activation by preventing mitochondrial dysfunction.

scholarly journals Exogenous stromal cell-derived factor-1 (SDF-1) suppresses the NLRP3 inflammasome and inhibits pyroptosis in synoviocytes from osteoarthritic joints via activation of the AMPK signaling pathway

2021 ◽  
Author(s):  
Shuya Wang ◽  
Ali Mobasheri ◽  
Yue Zhang ◽  
Yanli Wang ◽  
Tianqi Dai ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Nlrp3 Inflammasome ◽  
Stromal Cell ◽  
Underlying Mechanism ◽  
Inhibitory Effect ◽  
Healthy Individuals ◽  
Mtor Signaling Pathway ◽  
Ampk Signaling ◽  
Stromal Cell Derived Factor

Abstract Objective NLRP3 inflammasome may play a key role in OA pathogenesis. Stromal cell-derived factor-1 (SDF-1) is a homeostatic CXC chemokine. Since the role of SDF-1 in OA has not been explored, this study aimed to examine the effect of SDF-1 on NLRP3 inflammasome and pyroptosis in synoviocytes from OA joints. Materials and methods Human synovium was obtained from OA patients for isolation of primary synoviocytes and a murine model of collagenase-induced OA was established for testing intra-articular injections of SDF-1. Immunoblotting assays were used to examine the effects and underlying mechanism of action of SDF-1 on NLRP3 inflammasome and synoviocyte pyroptosis in synoviocytes. Inhibitors of AMPK and PI3K–mTOR were utilized to investigate the key signaling pathways involved in SDF-1-mediated OA inflammasome formation and pyroptosis. Results Synoviocytes from OA joints exhibited significantly higher expression of NLRP3 inflammasome and biomarkers of synoviocyte pyroptosis relative to healthy individuals. This was confirmed in the collagenase-induced OA model, where OA synoviocytes had a significantly lower SDF-1 expression than healthy ones. SDF-1 treatment in synoviocytes of OA patients and collagenase-induced OA led to significant downregulation in the expression of NLRP3 inflammasome and synoviocyte pyroptosis biomarkers. Inhibition of the AMPK signaling pathway significantly suppressed the inhibitory effect of SDF-1 on NLRP3 inflammasome expression of OA synoviocytes. However, blocking the SDF-1-activated PI3K–mTOR signaling pathway could still suppress the expression of NLRP3 inflammasome and synoviocyte pyroptosis biomarkers. Conclusions SDF-1 ameliorates NLRP3 inflammasome and pyroptosis in OA synoviocytes through activation of the AMPK signaling pathway. Therefore, SDF-1 may be a novel therapeutic target for OA.

scholarly journals SARS-CoV-2 spike glycoprotein S1 induces neuroinflammation in BV-2 microglia

2020 ◽  
Author(s):  
Olumayokun A Olajide ◽  
Victoria U Iwuanyanwu ◽  
Oyinkansola D Adegbola
Keyword(s):  
Protein Expression ◽  
P38 Mapk ◽  
Nlrp3 Inflammasome ◽  
Neuropsychiatric Symptoms ◽  
Spike Glycoprotein ◽  
Caspase 1 ◽  
Global Pandemic ◽  
Protein Expressions ◽  
Pre Treatment ◽  
Culture Supernatants

The emergence of SARS‐CoV‐2 has resulted in a global pandemic. In addition to respiratory complications as a result of SARS‐CoV‐2 illness, accumulating evidence suggests that neurological and neuropsychiatric symptoms are associated with the disease caused by the virus. In this study, we investigated the effects of the SARS‐CoV‐2 spike glycoprotein S1 stimulation on neuroinflammation in BV-2 microglia. Analyses of culture supernatants revealed an increase in the production of TNFα, IL-6, IL-1β and iNOS/NO. SARS‐CoV‐2 spike glycoprotein S1 increased protein expressions of phospho-p65 and phospho-IκB, as well as enhancing DNA binding and transcriptional activity of NF-κB. Pro-inflammatory effects of the glycoprotein effects were reduced in the presence of BAY11-7082 (1 μM). The presence of SARS‐CoV‐2 spike glycoprotein S1 in BV-2 microglia increased the protein expression of NLRP3, as well as caspase-1 activity. However, pre-treatment with CRID3 (1 μM) or BAY11-7082 (1 μM) resulted in the inhibition of NLRP3 inflammasome/caspase-1. It was also observed that CRID3 attenuated SARS‐CoV‐2 spike glycoprotein S1-induced increase in IL-1β production. Increased protein expression of p38 MAPK was observed in BV-2 microglia stimulated with the spike glycoprotein S1, and was reduced in the presence of SKF 86002. These results have provided the first evidence demonstrating SARS-CoV-2 spike S1 glycoprotein-induced neuroinflammation in BV-2 microglia. We propose that promotion of neuroinflammation by this glycoprotein is mediated through activation of NF-κB, NLRP3 inflammasome and p38 MAPK. These results are significant because of their relevance to our understanding of neurological and neuropsychiatric symptoms observed in patients infected with SARS-CoV-2.

scholarly journals Inhibitory effect of black raspberry extract on AGE accumulation and degradation, and ROS production in HUVEC cells

2020 ◽  
Vol 10 (6) ◽  
pp. 242
Author(s):  
Katsuaki Dan ◽  
Atsushi Takada ◽  
Yasunori Kanaho ◽  
Yuko Kusumi ◽  
Harutaka Banno
Keyword(s):  
Protein Expression ◽  
Inhibitory Effect ◽  
Expression Level ◽  
Mrna Levels ◽  
Ros Production ◽  
Black Raspberry ◽  
Cellular Events ◽  
Age Related ◽  
Berry Extracts ◽  
Age Receptors

Background: A critical event in age-related diseases involves the glycation of various proteins in the animal body to generate advanced glycation end products (AGEs). We have previously found that black raspberry extract (BRE) has effects on age-related diseases. From this observation, we expected that berry extracts, specifically BRE, would have positive effects on AGE-stimulated cell events that link to age-related diseases.Objective: To discuss the potency of berry extracts against diseases attributable to the AGE-dependent changes of cellular events, in this study, we examined the effects of berry extracts on the cellular events changed upon AGE stimulation of human umbilical vein endothelial cells (HUVECs) through AGE receptors.Methods: After HUVECs were incubated with AGE-BSA in the presence of serially diluted berry extracts, mRNA and protein levels of AGE receptors, intracellular AGE accumulation, and ROS production in the cell were determined by qRT-PCR and Western blotting, ELISA, and staining with the fluorescent probe, respectively.Results: Although concentration-dependent effects of berry extracts tested on mRNA levels of AGE receptors in HUVECs were not clear, mRNA level of the AGE receptor RAGE that is involved in the intracellular ROS production was increased by Blabina, which contains BRE, and the well-known anti-glycation compound aminoguanidine (AGD). In contrast, the protein expression level of RAGE was decreased by BRE and Blabina, but not by AGD. It was also found that BRE and Blabina suppressed AGE-BSA-stimulated ROS production in HUVECs. The extent of inhibition in the RAGE protein expression by BRE and Blabina was correlated well with the ROS generation measured in these samples.Conclusions: The results obtained in this study demonstrate that BRE has the most potent inhibitory effect on ROS accumulation in the cell, probably due to the suppression in the expression level of the RAGE protein. These observations suggest that black raspberry could be a potential nutraceutical to prevent various age-related diseases.Keywords: AGEs; RAGE; ROS; black raspberry; HUVECs. 

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