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IgA nephropathy is recognized as the most common primary glomerular disease， with up to 20%-40% of patients developing end-stage kidney disease within 20 years of onset. The deposition of IgA1-containing immune complexes targeting glycosylation defects in the mesangial region and the subsequent inflammation caused by T lymphocyte activation are considered as the main causes of IgA nephropathy， and innate immunity is also involved in the pathogenesis. Nucleotide-binding oligomerization domain （NOD）-like receptor protein 3 （NLRP3） is a newly discovered pattern recognition receptor expressed in renal intrinsic cells such as renal tubular epithelial cells， mesangial cells， and podocytes. Activated by external stimuli， NLRP3 can form NLRP3 inflammasomes with apoptosis-associated speck-like protein containing a caspase recruitment domain （ASC）. The NLRP3 inflammasome can activate cysteine aspartate-specific protease-1 （Caspase-1）， causing the maturation and release of interleukin-18 （IL-18） and interleukin-1β （IL-1β） involved in inflammation. Increasing evidence has suggested that NLRP3 inflammasomes are involved in the pathogenesis and progression of IgA nephropathy and associated with the damage of renal intrinsic cells such as podocytes， mesangial cells， endothelial cells， and renal tubular epithelial cells. Chinese medicine can regulate inflammatory cytokines and their signaling pathways by acting on NLRP3 inflammasomes and related molecules， exerting therapeutic effects on IgA nephropathy. This article introduces the role of NLRP3 inflammasomes in IgA nephropathy and reviews the clinical and experimental research progress of Chinese medicine intervention in IgA nephropathy via NLRP3 inflammasomes， aiming to provide a reference for further research and application of Chinese medicine intervention in the NLRP3 inflammasome as a new therapeutic target.
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Aim Excessive cerebral inflammation caused by chronic alcohol intake is an important risk factor for central nervous system injury. The purpose of this study was to explore the protective effect of konjac mannan oligosaccharide (KMOS) on central nervous system inflammation in alcohol-fed mice and its mechanism. Methods The chronic alcohol fed model of C57BL/6J mice was established using Gao-binge method. And the different doses of KMOS were gavaged every day for 6 weeks. The neuronal damage and microglia activation were evaluated in cerebral cortex and hippocampus. The damage of colon tissue was assessed and serum LPS concentrations were measured. In vitro, Caco-2 cells were stimulated with LPS to establish intestinal mucosal injury model. Results Chronic alcohol intake can cause brain neuron damage in mice, and different doses of KMOS effectively reduced the activation state of microglia, decreased the expression of inflammatory factors caused by the activation of the NLRP3 inflammasome and alleviated neuronal damage in the brain tissue of alcohol-fed mice. The results of colon tissue analysis showed that the use of KMOS effectively reduced the concentration of endotoxin LPS in serum of alcohol-fed mice, alleviated the pathological injury and inflammatory response of colon tissue, and enhanced the expression of Occludin in intestinal tissue. In vitro experiments also showed that KMOS significantly inhibited the inflammatory reaction of Caco-2 cells exposed to alcohol and increased the expression of Occludin protein. Conclusions KMOS treatment effectively inhibited intestinal inflammation caused by alcohol intake, repaired intestinal barrier to prevent the entry of intestinal LPS into brain tissue, decreased the activation of microglia, and then improved brain neuron damage. KMOS had the potential to prevent alcoholic nerve injury.
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Aim To explore the effect of berberine (B E) on RSV infected HEp-2 cells and the related mechanism. Methods HEp-2 cells were infected with RSV and treated with BE. Cell viability was assessed using the CCK-8 assay. Protein expression levels of NLRP3, ASC, caspase-1, PINK1, Parkin, Beclinl, p62, LC3 I,LC3 II,and BNIP3 in HEp-2 cells were detected by Western blot. The secretion level of IL-1 p in HEp-2 cells was measured using ELISA. Apoptosis rate and mitochondrial membrane potential of HEp-2 cells were examined by flow cytometry. Mitochondrial ROS (mtROS) in HEp-2 cells was detected through MitoSOX staining. Colocalization of mitochondria and autophagosomes in HEp-2 cells was investigated using immunofluorescence staining. Cyclosporin A was used for validation experiments. Results BE could significantly improve the activity of RSV-infected HEp-2 cells,reduce the apoptosis rate (P < 0. 05), and decrease the activation level of NLRP3 inflammasomes and IL-lp level (P <0. 05); BE improved mitochondrial function by increasing mitochondrial membrane potential and ATP levels,and reduced mtROS. BE significantly promoted the colocalization of mitochondria-autophagosome in RSV infected cells, inducing PINK1/ Parkin and BNIP3 to mediate mitochondrial autophagy; cyclosporine A aggravated RSV infection. Conclusions BE has protective effects on HEp-2 cells infected by RSV. The mechanism may be related to the inhibitory effect of BE on the production of mtROS and the activation of NLRP3 inflammasomes by inducing PINK1/ Parkin and BNIP3-mediated mitochondrial autophagy.
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The NLRP3 inflammasome is a cellular multimeric protein complex that plays a crucial role in inflammation and immune responses. It consists of three main components: Nod-like receptor protein 3(NLRP3), apoptosis-associated speck-like protein containing(ASC)and cysteine protease 1(caspase-1). Uveitis is a broad term encompassing a range of inflammatory diseases that primarily affect the iris, ciliary body, vitreous, retina and choroid. It is considered a major cause of blindness globally. Numerous studies have demonstrated the involvement of NLRP3 inflammasome in the onset and progression of uveitis, indicating its potential as a significant therapeutic target for uveitis in the future. This article provides an overview of the structure, biological functions and activation pathways of the NLRP3 inflammasome, as well as the current research progress on its association with different types of uveitis. Additionally, it discusses the application potential of the NLRP3 inflammasome in the treatment of uveitis.
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ObjectiveTo investigate the therapeutic effect of Scutellariae Radix-Coptidis Rhizoma （SRCR） on atherosclerosis （AS） in mice and the effect of SRCR on macrophage pyroptosis in plaques via NOD-like receptor thermal protein domain-associated protein 3 （NLRP3） inflammasomes. MethodApoE-/- mice were fed with a high-fat diet for the modeling of AS and randomized into model， atorvastatin （5 mg·kg-1）， and low-， medium-， and high-dose （1.95， 3.9， 7.8 g·kg-1， respectively） SRCR groups. Normal C57BL/6J mice were selected as the control group. After 8 weeks of administration， hematoxylin-eosin staining was used to observe the pathological status of the aortic plaque. The lipid accumulation in aortic plaque was observed by oil red O staining. The serum levels of total cholesterol （TC）， triglyceride （TG）， high-density lipoprotein cholesterol （HDL-C）， and low-density lipoprotein cholesterol （LDL-C） in mice were measured. Immunofluorescence double staining was employed to detect the co-localized expression of EGF-like module-containing mucin-like hormone receptor-like 1 （EMR1）/NLRP3 and EMR1/gasdermin D （GSDMD）. The serum levels of interleukin-1β （IL-1β） and interleukin-18 （IL-18） were determined by enzyme-linked immunosorbent assay （ELISA）. The protein levels of NLRP3， apoptosis-associated speck-like protein （ASC）， Caspase-1， cleaved Caspase-1， GSDMD， N-terminus of GSDMD （GSDMD-NT）， pro-IL-1β， IL-1β， and IL-18 were determined by Western blot， and the mRNA levels of NLRP3， ASC， Caspase-1， GSDMD， IL-1β， and IL-18 were determined by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. ResultCompared with the control group， the model group showed obvious plaques， elevated serum levels of TG， TC， LDL-C， IL-1β， and IL-18 （P<0.01）， lowered serum level of HDL-C （P<0.01）， and up-regulated expression of NLRP3 inflammasomes and molecules related to pyroptosis in the aortic plaques （P<0.01）. Compared with the model group， SRCR， especially at the medium and high doses， alleviated the plaque pathology， reduced the lipid content in plaques （P<0.05， P<0.01）， recovered the serum lipid levels （P<0.05）， reduced the macrophage recruitment （P<0.01）， activation of NLRP3 inflammasomes， and pyroptosis in aortic root plaques （P<0.05）， lowered the serum IL-1β and IL-18 levels （P<0.01）， and down-regulated the protein levels of NLRP3， ASC， Caspase-1， cleaved Caspase-1， GSDMD， GSDMD-NT， pro-IL-1β， IL-1β， and IL-18 （P<0.05） and the mRNA levels of NLRP3， ASC， Caspase-1， GSDMD， IL-1β， and IL-18 in the aortic tissue （P<0.05）. ConclusionSRCR exerts a therapeutic effect on high-fat diet-induced AS in mice by inhibiting the activation NLRP3 inflammasomes and reducing the pyroptosis of macrophages in plaques.
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Resumen La cardiomiopatía diabética es una complicación grave de la diabetes causada por estrés oxidativo, inflamación, resistencia a la insulina, fibrosis miocárdica y lipotoxicidad. Se trata de un padecimiento insidioso, complejo y difícil de tratar. El inflamasoma NLRP3 desencadena la maduración y liberación de citoquinas proinflamatorias, participa en procesos fisiopatológicos como la resistencia a la insulina y la fibrosis miocárdica, además de estar estrechamente relacionado con la aparición y progresión de la cardiomiopatía diabética. El desarrollo de inhibidores dirigidos a aspectos específicos de la inflamación sugiere que el inflamasoma NLRP3 puede utilizarse para tratar la cardiomiopatía diabética. Este artículo pretende resumir el mecanismo y las dianas terapéuticas del inflamasoma NLRP3 en la cardiomiopatía diabética, así como aportar nuevas sugerencias para el tratamiento de esta enfermedad.
Abstract Diabetic cardiomyopathy (DCM) is a serious complication of diabetes caused by oxidative stress, inflammation, insulin resistance, myocardial fibrosis, and lipotoxicity; its nature is insidious, complex and difficult to treat. NLRP3 inflammasome triggers the maturation and release of pro-inflammatory cytokines, participates in pathophysiological processes such as insulin resistance and myocardial fibrosis, in addition to being closely related to the development and progression of diabetic cardiomyopathy. The development of inhibitors targeting specific aspects of inflammation suggests that NLRP3 inflammasome can be used to treat diabetic cardiomyopathy. This paper aims to summarize NLRP3 inflammasome mechanism and therapeutic targets in diabetic cardiomyopathy, and to provide new suggestions for the treatment of this disease.
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ObjectiveTo observe the effect of Huanglian Jiedutang on the inflammatory injury in the mouse model of acute gouty arthritis （AGA） and to explore the mechanism of Huanglian Jiedutang in treating AGA. MethodForty male C57BL/6J mice were randomized into blank， model， colchicine （0.83 mg·kg-1）， and Huanglian Jiedutang （5 g·kg-1） groups. The mouse model of AGA was established by injecting monosodium urate （MSU） crystals into the ankle joint. The swelling degree of the right ankle joint of each mouse was measured every day for 7 days， and the pathological changes of the ankle joint were detected by hematoxylin-eosin （HE） staining after 7 days. The other 40 C57BL/6J mice were grouped as above. After 18 hours of modeling， the right ankle joint was collected， and real-time polymerase chain reaction was employed to measure the mRNA levels of interleukin （IL）-1β， tumor necrosis factor （TNF）-α， IL-6， NOD-like receptor protein 3 （NLRP3）， apoptosis-associated speck-like protein containing a CARD （ASC）， and Caspase-1. The expression levels of IL-1β， TNF-α， and IL-6 were measured by the enzyme-linked immunosorbent assay. Western blot was employed to determine the protein levels of NLRP3 inflammasome， Toll-like receptor 4 （TLR4）， and nuclear factor-κB （NF-κB）. ResultCompared with the blank group， the model group showed swelling right ankle joint （P<0.01）， obvious foreign body granuloma in the ankle joint with inflammatory cell infiltration. After the treatment with Huanglian Jiedutang， the ankle joint swelling was relieved （P<0.05， P<0.01）， and the size of foreign body granuloma was reduced. Compared with the blank group， the model group showed up-regulated mRNA levels of IL-1β， TNF-α， and IL-6 in the ankle joint tissue （P<0.01）， up-regulated mRNA levels of NLRP3 and Caspase-1 in the NLRP3 inflammasome （P<0.05， P<0.01）， and up-regulated protein levels of NLRP3， Caspase-1， TLR4， and NF-κB （P<0.05， P<0.01）. Huanglian Jiedutang down-regulated the mRNA levels of IL-1β， TNF-α， IL-6， NLRP3， and Caspase-1 （P<0.05， P<0.01） and the protein levels of IL-1β， TNF-α， IL-6， NLRP3， Caspase-1， TLR4， and NF-κB （P<0.05 or P<0.01）. ConclusionInjecting MSU crystal resulted in local inflammatory injury of the joints in the mouse model of AGA. The treatment with Huanglian Jiedutang may alleviate the inflammatory injury by regulating the NLRP3 inflammasome and TLR4/NF-κB signaling pathway.
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The prevalence of osteoporosis， osteoarthritis， gouty arthritis， rheumatoid arthritis， and intervertebral disc degeneration is increasing year by year with the growing number of elderly people， and the common clinical manifestations of these diseases include severe pain in different areas， which seriously affects the daily life of the patients. Therefore， how to relieve the pain and reduce the prevalence of bone and joint diseases and improve the quality of life of the patients is a hot spot in the medical field. Studies have confirmed that NOD-like receptor family， pyrin domain-containing protein 3 （NLRP3） inflammasomes， as pattern recognition receptors， are involved in the inflammation， chondrocyte proliferation， osteoblast and osteoclast differentiation， intervertebral disc cell inflammation and scorching， extracellular matrix degradation and apoptosis， mitochondrial dysfunction， endoplasmic reticulum stress， and reactive oxygen species damage， demonstrating close link with the development of bone and joint diseases. Chinese medicine has a long history and demonstrates remarkable therapeutic effects in the treatment of bone and joint diseases. It can mitigate the pathological changes of bone and joint diseases by inhibiting NLRP3 inflammasomes to alleviate the pain， playing a role in preventing and treating these diseases. Therefore， this paper briefly describes the relationship between NLRP3 inflammasomes and the development of bone and joint diseases by reviewing the latest research progress at home and abroad. We summarize the latest studies about the active components， extracts， and compound prescriptions of Chinese medicines in the treatment of bone and joint diseases via regulating NLRP3 inflammasomes. This review is expected to offer new insights into the in-depth research on the pathogenesis and drug treatment of bone and joint diseases and provide a basis for the clinical application of Chinese medicine in the prevention and treatment of such diseases.
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Objective:To investigate the effect and regulation of umbilical cord-derived mesenchymal stem cells (UC-MSCs) on islets function and NOD-like receptor family, pyrin domain containing 3 (NLRP3) and autophagy in type 2 diabetic mellitus (T2DM) mice.Methods:Experimental study. Twenty, 8-week-old, male C57BL/6J mice were selected and divided into a normal control group ( n=5) and a high-fat feeding modeling group ( n=15). The model of T2DM was established by high-fat feeding combined with intraperitoneal injection of low-dose streptozotocin. After successful modeling, those mice were divided into a diabetes group ( n=7) and a UC-MSCs treatment group ( n=7). The UC-MSCs treatment group was given UC-MSCs (1×10 6/0.2 ml phosphate buffer solution) by tail vein infusion once a week for a total of 4 weeks; the diabetes group was injected with the same amount of normal saline, and the normal control group was not treated. One week after the treatment, mice underwent intraperitoneal glucose tolerance tests and intraperitoneal insulin tolerance tests, and then the mice were sacrificed to obtain pancreatic tissue to detect the expressions of interleukin-1β (IL-1β) and pancreatic and duodenal homeobox 1 (PDX-1) by immunofluorescence. The bone marrow-derived macrophages were stimulated with lipopolysaccharide and adenosine triphosphate (experimental group) in vitro, then co-cultured with UC-MSCs for 24 h (treatment group). After the culture, enzyme-linked immunosorbent assay was used to detect the secretion level of IL-1β in the supernatant, and immunofluorescence staining was used to detect the expression of NLRP3 inflammasome, and related autophagy proteins. Statistical analysis was performed using unpaired one-way analysis of variance, repeated measure analysis of variance. Results:In vivo experiments showed that compared with the diabetes group, the UC-MSCs treatment group partially repaired islet structure, improved glucose tolerance and insulin sensitivity (all P<0.05), and the expression of PDX-1 increased and IL-1β decreased in islets under confocal microscopy. In vitro experiments showed that compared with the experimental group, the level of IL-1β secreted by macrophages in the treatment group was decreased [(85.9±74.6) pg/ml vs. (883.4±446.2) pg/ml, P=0.001], the expression of NLRP3 inflammasome and autophagy-related protein P62 was decreased, and the expressions of microtubule-associated protein 1 light chain 3β (LC3) and autophagy effector Beclin-1 were increased under confocal microscopy. Conclusions:UC-MSCs can reduce the level of pancreatic inflammation in T2DM mice, preserving pancreatic function. This might be associated with the ability of UC-MSCs to inhibit the activity of NLRP3 inflammasomes in macrophages and enhance autophagy levels.
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OBJECTIVE Alzheimer disease(AD)is a neurodegenerative disease with clinical hallmarks of pro-gressive cognitive impairment.Synergistic effects of Aβ-tau cascade reaction are tightly implicated in AD patholo-gy,and microglial NLRP3 inflammasome activation drives neuronal tauopathy through microglia and neurons cross-talk.However,the underlying mechanism of how Aβ medi-ates NLRP3 inflammasome remains unclear.Shab related potassium channel member 1(Kv2.1)as a voltage gated po-tassium channel widely distributed in the central nervous system and plays an important role in regulating the out-ward potassium flow in neurons and glial cells.In current work,we aimed to explore the underlying mechanism of Kv2.1 in regulating Aβ/NLRP3 inflammasome/tau axis by using a determined Kv2.1 inhibitor drofenine(Dfe).METHODS Cell-based assays including Western blot-ting and immunofluorescence staining against primary microglia or neurons were carried out to expound the role of Kv2.1 channel in NLRP3 inflammasome activa-tion and subsequent neuronal tau hyperphosphorylation.For animal studies,new object recognition,Y-maze and Morris water maze were performed to evaluate the ame-lioration of Kv2.1 inhibition through either Kv2.1 inhibitor Dfe treatment or adeno-associated virus AAV-ePHP-si-Kv2.1injectionon5×FADADmodel mice.Assays of histol-ogy and immunostaining of tissue sections and Western blotting of brain tissues were performed to verify the con-clusion of cellular assays.RESULTS We reported that oligomeric Aβ(o-Aβ)bound to microglial Kv2.1 and pro-moted Kv2.1-dependent potassium leakage to activate NLRP3 inflammasome through JNK/NF-κB pathway sub-sequently resulting in neuronal tauopathy.Treatment of either Kv2.1 inhibitor Dfe or AAV-ePHP-si-Kv2.1 for brain-specific Kv2.1 knockdown deprived o-A β of its capability in inducing microglial NLRP3 inflammasome activation and neuronal tau hyperphosphorylation,while improved the cognitive impairment of 5×FAD AD model mice.CONCLUSION Our results have highly addressed that Kv2.1 channel is required for o-Aβ driving NLRP3 inflammasome activation and neuronal tauopathy in AD model mice and highlighted that Kv2.1 inhibition is a prom-ising therapeutical strategy for AD and Dfe as a Kv2.1 inhibitor shows potential in the treatment of this disease.
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OBJECTIVE In this study,the effects of live Lactobacillus murinus(L.m)and heat-killed L.muri-nus(H-k L.m)on DA neuronal damage in rats and the underlying mechanisms were investigated.METHODS Male SD rats were randomly divided into five groups:vehicle group,L.m/H-k L.m(1×109 cfu)group,6-OHDH group,6-OHDH + L.m/H-k L.m(1×107 cfu)group,and 6-OHDH + L.m/H-k L.m(1×109 cfu)group.Wild-type and NLRP3 knockout mice were divided into three groups:sham(vehicle),6-OHDH,and 6-OHDH + H-k L.m(1×109 cfu).The model was established after five weeks of pre-administration.Motor ability of experimental mice was assessed by rotarod,mine,and stepping experiments;the expression of dopaminergic neuron markers—tyro-sine hydroxylase(TH),microglial cell markers—ionized calnexin 1(IBA-1),and NOD-like receptor family protein 3(NLRP3)in the substantia nigra was detected by immunohistochemistry and immunofluorescence experi-ments.The expression changes of TH,IBA-1,NLRP3,apoptosis-associated microparticle protein(ASC),cas-pase 1,and inflammatory factors such as interleukin-1β(IL-1β),IL-18,and tumor necrosis factor-α(TNF-α)were detected by immunoblotting experiments.RESULTS H-k L.m ameliorated 6-OHDH-induced motor dysfunctions and loss of substantia nigra DA neurons,while no protec-tion was shown in live L.m treatment.At the same time,H-k L.m reduced the activation of NLRP3 inflammasome in microglia and the secretion of pro-inflammatory factors,thus inhibiting the development of neuroinflammation.Fur-thermore,H-k L.m failed to display its original neuropro-tective properties in NLRP3 inflammasome knockout mice.CONCLUSION H-k L.m conferred neuroprotec-tion against DA neuronal loss via the inhibition of microglial NLRP3 inflammasome activation,these findings provide a promising potential for future applications of L.m,and also beneficial strategy for PD treatment.
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OBJECTIVE Alzheimer's disease(AD)is the most common neurodegenerative disease worldwide.Neuroinflammation is a potential target for the patients with AD.It is attributed to activated microglia and the release of various inflammatory mediators from infec-tion,ischemia and toxin accumulation.Accumulating evi-dence has indicated that the cGAS-STING pathway driven neuroinflammation in neurological disease.TSG is a main natural active ingredient that derived from polyg-onum multiflorum.Previous research from our group found that TSG has beneficial effects of anti-aging,anti-inflammatory action and improving memory function in APP/PS1 transgenic AD mice.Here,we investigated the effects of TSG on cognitive impairment and neuroinflam-mation in APP/PS1-AD mice and explore the underly-ing mechanism by which TSG ameliorates memory func-tion in the cGAS-STING-mediated inflammatory response.METHODS The Morris water mace test and the novel object recognition test were performed to test the effects of TSG on spatial learning and cognitive and memory abil-ity in APP/PS1 double transgenic AD mice model.In addi-tion,real-time quantitative PCR,Western blotting,ELISA analysis,and flow cytometry to examine gene and pro-tein expression of cGAS-STING related pro-inflammatory cytokines and chemokines.Statistical analyses were ana-lyzed using the SPSS 25.0 package by analysis of vari-ance(ANOVA).Neuman-Keuls or Tukey's multiple-com-parisons test were conducted as ANOVA justified post hoc comparisons between group means.RESULTS We demonstrated that AD transgenic mice exhibited cognitive deficits accompanied by the elevated serum and brain inflammation.The expressions of serum inflammatory cytokines and the activation of microglia in cerebral cor-tex and hippocampus were suppressed after TSG treat-ment,which was probably attributable to the decrease of cyclic GMP-AMP synthase(cGAS)and stimulator of interferon genes(STING)triggered immune response.Additionally,the data showed that TSG treatment reduced the expression level of inflammatory cytokines(IL-1β,TNF-α,IFN-β,IFN-α)in microglial cells BV2 primed with LPS and IFN-γ.CONCLUSION TSG implicated the health benefits in preventing cognitive disorders by inhib-iting neuroinflammation via cGAS-STING signalling path-way in AD.
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OBJECTIVE To investigate the effects of pharmacological inhibition of STING by C-176,a STING selective inhibitor,in experimental model of Parkinson's disease.METHODS The acute and sub-acute mice mod-els of Parkinson's disease(PD)were established by in-traperitoneal injection of 1-methyl-4-(2′-methylphenyl)-1,2,3,6-tetrahydrophine(MPTP).The selective STING inhibitor C-176 was administered by intraperitoneal injec-tion.The potential neuroprotective effects of C-176 were evaluated by behavioral test,tyrosine hydroxylase(TH)immunostaining,Nissl staining,Western blotting,qPCR and immunofluorescence.For in vitro study,the effects of C-176 on LPS/MPP+-induced inflammatory responses in BV2 microglial cells were determined by real time RT-PCR and Western blotting analysis.RESULTS Our study revealed that C-176 significantly inhibited STING signaling activation,ameliorated MPTP-induced dopami-nergic neurotoxicity,motor deficit and associated neuroin-flammation.Furthermore,pharmacological inhibition of STING in BV2 microglia treated with LPS/MPP+ exhibited decreased inflammatory responses.More importantly,C176 also reduced NLRP3 inflammasome activation both in vitro and in vivo.CONCLUSION The results of our study suggest that pharmacologic inhibition of STING protects against neuroinflammation that may act at least in part through suppressing NLRP3 inflammasome acti-vation and thus ameliorated dopaminergic neurodegener-ation.STING signaling may holds great promise for the development of new treatment strategy for PD as an effective therapeutic target.
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Objective:To investigate the effects of NOD-like receptor protein 3(NLRP3) inflammasome activation on the proliferation, migration and extracellular matrix desposition of activated pancreatic stellate cells(PSCs).Methods:The rat PSCs were isolated, cultured and identified, and were divided into control group or LPS group based on the pretreatment with LPS (10 μg/ml for 24 hours) or without. The expression of NLRP3 inflammasome associated molecules in PSCs culture medium was detected by ELISA. The PSCs with NLRP3 inhibition were constructed by shRNA carrying lentivirus infection and were divided into LPS+ negative control group and LPS+ lentivirus group based on whether the cells were treated with LPS and infected by lentivirus or not. The alteration in cell proliferation and migration were detected by CCK-8 kit and transwell chamber method. The expression of extracellular matrix α-SMA and collagen in PSCs was detected by immunofluorescence staining and the expression of TGF-β mRNA was analyzed by RT-qPCR.Results:The cytoplasm of PSCs which were cultured for 24 hours was rich in bright annular lipid droplets, and the cells expressed desmin. After 7 days of culture, the cell became larger in size, the lipid droplets basically disappeared, and the cells were activated and expressed α-SMA. The expression of caspase-1, IL-1β and IL-18 in the supernatant of PSCs culture medium in LPS group were significantly higher than those in control group (1.55±0.04 vs 0.65±0.03), (2.02±0.04 vs 1.05±0.05) and (1.70±0.05 vs 0.97±0.03), respectively. After inhibiting by lentivirus infection, the expression of NLRP3 in the lentivirus group (0.25±0.04) was significantly lower than that in negative control group (0.68±0.05). In control group, LPS group, LPS+ negative control group and LPS+ lentivirus group, the A490 values was 0.61±0.02, 1.15±0.06, 0.96±0.05, and 0.56±0.01, respectively; the migrating PSCs number was (64.12±4.58), (121.67±8.02), (111.67±4.67) and (69.67±8.08)/HF, respectively; the relative expression of α-SMA was 0.78±0.05, 4.12±0.04, 3.81±0.06 and 0.88±0.05, respectively; the relative expression of collagen was 0.65±0.03, 3.43±0.02, 2.67±0.02 and 0.48±0.03, respectively; and the expression of TGF-β mRNA was 0.22±0.03, 0.89±0.01, 0.86±0.03 and 0.43±0.02, respectively. The A490 value, the migrating cells number, the expression of α-SMA, collagen and the expression of TGF-β mRNA in LPS group and LPS+ negative control group was significantly higher than those in control group and LPS+ lentivirus group, and all the differences were statistically significant (all P value <0.05). Conclusions:NLRP3 inflammasome activation may accelerate the extracellular matrix deposition and pancreatic fibrogenesis by promoting PSCs proliferation and migration ability via regulating the biological functions.
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Acute respiratory infections are the most common infectious diseases in children.Among them, respiratory viruses are the main pathogens that cause many respiratory diseases, system damages or even death.As the first line of defense against pathogens like respiratory viruses, the innate immune system recognizes the structural components of viruses and endogenous danger signals with the pattern recognition receptors on immune cells and epithelial cells.During this process, inflammasomes are assembled and activated, and they participate in the recognition of viruses, inflammatory and immune response against viruses.The present study aims to describe the composition and function of inflammasomes, as well as the activation and negative regulation mechanisms of inflammasomes during common respiratory infections.
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Objective:To observe the effects of different doses of Gegen Qinlian Decoction on nucleotide oligomeric domain-like receptor protein 3 (NLRP3)/Caspase-1/IL1β inflammatory signaling pathway in liver of db/db mice with type 2 diabetes mellitus (T2DM).Methods:Totally 75 SPF male db/db mice were randomly divided into model group, metformin group (0.2 g/kg), Gegen Qinlian Decoction high-, medium-, and low-dosage groups (61.80, 30.90, 15.45 g/kg), with 15 mice in each group. Another 15 db/m male mice were selected as blank control group. Each administration group was given relevant medicine for gavage, while the blank group and model group were given 0.9% sodium chloride solution for gavage, once a day, for 12 weeks. The body weight, fasting blood glucose (FBG) and glycosylated hemoglobin (HbA1c) contents of each group were measured after treatment. The mRNA expression levels of NLRP3, Caspase-1 and interleukin-1β (IL-1β) in liver were detected by real-time quantitative PCR. The expression levels of NLRP3, Caspase-1, IL-1β and IL-18 in liver tissues were detected by Western Blot. HE staining was used to observe the morphology of liver tissues.Results:Compared with model group, body weight, fasting blood glucose and HbA1c contents of mice in Gegen Qinlian Decoction high- and medium-dosage groups and metformin groups decreased ( P<0.05), the body weight and fasting blood glucose levels of mice in Gegen Qinlian Decoction low-dosage group decreased ( P<0.05); the mRNA levels of NLRP3 and IL-1β in liver tissues of all treatment groups decreased ( P<0.05), the mRNA level of Caspase-1 in liver tissue decreased in Gegen Qinlian Decoction high- and medium-dosage groups ( P<0.05); the expression of NLRP3, Caspase-1, and IL-18 in liver tissue of each treatment group decreased ( P<0.05), while the expression of IL-1β in Gegen Qinlian Decoction high- and medium-dosage groups and the metformin group decreased ( P<0.05); compared with the metformin group, the body weight and fasting blood glucose of mice in the Gegen Qinlian Decoction high-dosage decreased ( P<0.05), while the HbA1c levels in the Qinlian Decoction high- and medium-dosage decreased ( P<0.05); the expressions of NLRP3, Caspase-1 and IL-18 in liver tissues of Gegen Qinlian Decoction high-dosage group decreased ( P<0.05), the expression of IL-1β, NLRP3, Caspase-1, IL-1β, and IL-18 decreased ( P<0.05); HE staining showed that the pathological changes of liver tissue were reduced in all treatment groups. Conclusion:Gegen Qinlian Decoction may reduce blood sugar by inhibiting the activation of NLRP3/Caspase-1/IL-1β inflammatory signaling pathway in liver of db/db mice, thereby improving the inflammatory damage of T2DM.
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Atherosclerosis is a chronic inflammatory disease caused by lipid accumulation and vascular endothelial dysfunction. The Toll-like receptor （TLR）/nuclear transcription factor-κB （NF-κB） pathway and the NOD-like receptor protein 3 （NLRP3） inflammasome pathway play a proinflammatory role， while the transient receptor potential vanilloid subtype 1 （TRPV1） and transient receptor potential ankyrin 1 （TRPA1） play a protective role in the occurrence of atherosclerosis. We reviewed the relevant studies published in the last 10 years. The results showed that activation of TRPV1/TRPA1 could activate endothelial-type nitric oxide synthase （eNOS） and inhibit the generation of reactive oxygen species （ROS） and cholesterol crystal （CC） to modulate the TLR/NF-κB and NLRP3 inflammasome pathways， thereby inhibiting TLR/NLRP3-mediated inflammatory response. A variety of compound prescriptions and active components of Chinese medicinal materials can activate TRPV1/TRPA1 or its downstream pathway to regulate the TLR/NLRP3 pathway in atherosclerosis. This paper introduces the mechanisms of compound prescriptions and active components of Chinese medicinal materials in regulating the TLR/NLRP3 pathway via TRPV1/TRPA1 in atherosclerosis. This review provides new ideas for the research on the interactions between Chinese medicines in the treatment of atherosclerosis and provides a new strategy for the clinical treatment of atherosclerosis with traditional Chinese medicine.
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OBJECTIVE@#To examine the anti-inflammatory effects and potential mechanisms of polypeptide from Moschus (PPM) in lipopolysaccharide (LPS)-induced THP-1 macrophages and BALB/c mice.@*METHODS@#The polypeptide was extracted from Moschus and analyzed by high-performance liquid chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Subsequently, LPS was used to induce inflammation in THP-1 macrophages and BALB/c mice. In LPS-treated or untreated THP-1 macrophages, cell viability was observed by cell counting kit 8 and lactate dehydrogenase release assays; the proinflammatory cytokines and reactive oxygen species (ROS) were measured by enzyme-linked immunosorbent assay and flow cytometry, respectively; and protein and mRNA levels were measured by Western blot and real-time quantitative polymerase chain reaction (qRT-PCR), respectively. In LPS-induced BALB/c mice, the proinflammatory cytokines were measured, and lung histology and cytokines were observed by hematoxylin and eosin (HE) and immunohistochemical (IHC) staining, respectively.@*RESULTS@#The SDS-PAGE results suggested that the molecular weight of purified PPM was in the range of 10-26 kD. In vitro, PPM reduced the production of interleukin 1β (IL-1β), IL-18, tumor necrosis factor α (TNF-α), IL-6 and ROS in LPS-induced THP-1 macrophages (P<0.01). Western blot analysis demonstrated that PPM inhibited LPS-induced nuclear factor κB (NF-κB) pathway and thioredoxin interacting protein (TXNIP)/nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain containing 3 (NLRP3) inflammasome pathway by reducing protein expression of phospho-NF-κB p65, phospho-inhibitors of NF-κB (Iκ Bs) kinase α/β (IKKα/β), TXNIP, NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), and pro-caspase-1 (P<0.05 or P<0.01). In addition, qRT-PCR revealed the inhibitory effects of PPM on the mRNA levels of TXNIP, NLRP3, ASC, and caspase-1 (P<0.05 or P<0.01). Furthermore, in LPS-induced BALB/c mice, PPM reduced TNF-α and IL-6 levels in serum (P<0.05 or P<0.01), decreased IL-1β and IL-18 levels in the lungs (P<0.01) and alleviated pathological injury to the lungs.@*CONCLUSION@#PPM could attenuate LPS-induced inflammation by inhibiting the NF-κB-ROS/NLRP3 pathway, and may be a novel potential candidate drug for treating inflammation and inflammation-related diseases.
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OBJECTIVE@#To observe the effects of electroacupuncture (EA) on NLRP3 inflammasome and its downstream protein gastermin D (GSDMD) in rats with primary dysmenorrhea (PDM), and to explore the potential mechanism of EA on the treatment of PDM.@*METHODS@#Forty healthy female SD rats without pregnancy were randomly divided into a control group, a model group, an EA group and an ibuprofen group, 10 rats in each group. PDM model was prepared by injection of estradiol benzoate and oxytocin. Except the control group, the rats in each group were subcutaneously injected with estradiol benzoate for 10 days, and oxytocin was injected on the 11th day. The rats in the EA group were intervened with EA (dense wave, frequency of 50 Hz) at "Guanyuan" (CV 4) and "Sanyinjiao" (SP 6) at the same time of modeling, once a day, 20 min each time, for 10 consecutive days. The rats in the ibuprofen group were treated with 0.8 mL of ibuprofen by gavage (concentration of ibuprofen solution was 1.25 mg/mL) for 10 consecutive days. After modeling, the writhing reaction was observed. After intervention, the HE staining method was used to observe the histological morphology of uterus and evaluate the pathological damage score of uterus; ELISA method was used to detect the serum levels of prostaglandin E2 (PGE2) and prostaglandin F2α (PGF2α); Western blot method was used to detect the protein expression of NLRP3, apoptosis related spot like protein (ASC), caspase-1, GSDMD, GSDMD-N and inflammatory factors (interleukin [IL]-1β, IL-18) in uterine tissue.@*RESULTS@#In the model group, a large number of vacuolar degeneration and death of endometrial epithelial cells, spiral arterioles congestion in lamina propria and neutrophil infiltration were observed. In the EA group, there was a small amount of vacuolar degeneration and death of endometrial epithelial cells, a small amount of spiral arterioles congestion in the lamina propria, and a small amount of neutrophils infiltration. In the ibuprofen group, there was very small number of degeneration and death of endometrial epithelial cells, and no obvious arterial congestion was found in lamina propria, and neutrophil infiltration was occasionally seen. Compared with the control group, in the model group the number of writhing was increased (P<0.01), the writhing reaction score and serum level of PGF2α and PGF2α/PGE2 value were increased (P<0.01), the level of PGE2 was decreased (P<0.01). Compared with the model group, in the EA group and the ibuprofen group the number of writhing were decreased (P<0.05), the latency of writhing was prolonged (P<0.01), the writhing reaction scores and serum levels of PGF2α and PGF2α/PGE2 values were decreased (P<0.05, P<0.01), the levels of PGE2 were increased (P<0.01). Compared with the control group, the protein expression of NLRP3, ASC, caspase-1, GSDMD, GSDMD-N, IL-1β and IL-18 in the uterine tissues of rats was increased in the model group (P<0.01). Compared with the model group, the protein expression of NLRP3, ASC, caspase-1, GSDMD, GSDMD-N, IL-1β and IL-18 in the uterine tissues of rats was decreased in the EA group and the ibuprofen group (P<0.01, P<0.05). There was no significant difference between the EA group and the ibuprofen group in the above indexes (P>0.05).@*CONCLUSION@#EA could alleviate pain and uterine tissue injury in rats with PDM. The mechanism may be related to the inhibition of the activation of NLRP3 inflammasome in rat uterine tissues, thereby inhibiting pyroptosis and its inflammatory factors release.
Subject(s)
Animals , Female , Pregnancy , Rats , Caspases , Dinoprost , Dinoprostone , Dysmenorrhea , Electroacupuncture , Ibuprofen , Inflammasomes , Interleukin-18 , NLR Family, Pyrin Domain-Containing 3 Protein , Oxytocin , Phosphate-Binding Proteins , Pyroptosis , Rats, Sprague-Dawley , UterusABSTRACT
Background: Pyroptosis is involved in the occurrence of acute pancreatitis, but its role in remote organ injury remains unclear. Aims: To investigate the role and mechanism of NLRP3 inflammasome-dependent pyroptosis in acute pancreatitis- related lung injury. Methods: Thirty-two male Sprague-Dawley rats were randomly divided into four groups: control group, severe acute pancreatitis (SAP) group, Z-WEHD-FMK (caspase-1 inhibitor) group and disulfiram (GSDMD inhibitor) group. Experimental SAP was constructed by using 5% sodium taurocholate in the latter 3 groups. Serum levels of amylase, lipase, procalcitonin, and the myeloperoxidase (MPO) activity were determined; the severity of pancreatic and lung injuries was assessed by histopathology and lung wet/dry weight ratio; serum levels of pyroptosis-related inflammatory cytokines and the expressions of proteins involved in pyroptosis pathway in lung tissue were measured by ELISA method and immunohisto- chemistry and Western blotting, respectively. Results: Compared with the control group, the serum biochemical indices, MPO activity, and interleukin (IL)-1β, IL-18 levels in SAP group were significantly increased with aggravated pancreatic and lung tissue injuries; meanwhile, the expressions of NLRP3, caspase-1 and GSDMD in lung tissue were significantly up- regulated (all P<0.05). Pretreatment with caspase-1 or GSDMD inhibitors reduced the severity of pancreatic and lung tissue injuries, improved the serum biochemical indices and MPO activity, and ameliorated the increased pyroptosis - related inflammatory cytokines and pyroptosis pathway - related proteins (all P<0.05). Conclusions: NLRP3/caspase - 1/GSDMD pathway mediated pyroptosis plays an important role in acute pancreatitis-related lung injury, and inhibition of pyroptosis pathways might be a new direction for its treatment.