scholarly journals Withaferin A alleviates fulminant hepatitis by targeting macrophage and NLRP3

2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Yangliu Xia ◽  
Ping Wang ◽  
Nana Yan ◽  
Frank J. Gonzalez ◽  
Tingting Yan
Keyword(s):  
Fulminant Hepatitis ◽  
Gene Knockout ◽  
Specific Inhibitor ◽  
Hepatoprotective Effect ◽  
Withaferin A ◽  
Inflammasome Activation ◽  
Therapeutic Effects ◽  
Related Factor ◽  
Wild Type

AbstractFulminant hepatitis (FH) is an incurable clinical syndrome where novel therapeutics are warranted. Withaferin A (WA), isolated from herb Withania Somnifera, is a hepatoprotective agent. Whether and how WA improves D-galactosamine (GalN)/lipopolysaccharide (LPS)-induced FH is unknown. This study was to evaluate the hepatoprotective role and mechanism of WA in GalN/LPS-induced FH. To determine the preventive and therapeutic effects of WA, wild-type mice were dosed with WA 0.5 h before or 2 h after GalN treatment, followed by LPS 30 min later, and then killed 6 h after LPS treatment. To explore the mechanism of the protective effect, the macrophage scavenger clodronate, autophagy inhibitor 3-methyladenine, or gene knockout mouse lines NLR family pyrin domain containing 3 (Nlrp3)-null, nuclear factor-erythroid 2-related factor 2 (Nrf2)-null, liver-specific AMP-activated protein kinase (Ampk)a1 knockout (Ampka1ΔHep) and liver-specific inhibitor of KB kinase β (Ikkb) knockout (IkkbΔHep) mice were subjected to GalN/LPS-induced FH. In wild-type mice, WA potently prevented GalN/LPS-induced FH and inhibited hepatic NLRP3 inflammasome activation, and upregulated NRF2 and autophagy signaling. Studies with Nrf2-null, Ampka1ΔHep, and IkkbΔHep mice demonstrated that the hepatoprotective effect was independent of NRF2, hepatic AMPKα1, and IκκB. Similarly, 3-methyladenine cotreatment failed to abolish the hepatoprotective effect of WA. The hepatoprotective effect of WA against GalN/LPS-induced FH was abolished after macrophage depletion, and partially reduced in Nlrp3-null mice. Consistently, WA alleviated LPS-induced inflammation partially dependent on the presence of NLRP3 in primary macrophage in vitro. Notably, WA potently and therapeutically attenuated GalN/LPS-induced hepatotoxicity. In conclusion, WA improves GalN/LPS-induced hepatotoxicity by targeting macrophage partially dependent on NLRP3 antagonism, while largely independent of NRF2 signaling, autophagy induction, and hepatic AMPKα1 and IκκB. These results support the concept of treating FH by pharmacologically targeting macrophage and suggest that WA has the potential to be repurposed for clinically treating FH as an immunoregulator.

scholarly journals 650 Target the activin receptor 1c on CD4+ T cells to achieve anti-tumor therapeutic effects

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A679-A679
Author(s):  
Ying Zheng ◽  
Andriana Lebid ◽  
Andrew Pardoll ◽  
Juan Fu ◽  
Chirag Patel ◽  
...  
Keyword(s):  
T Cells ◽  
Regulatory T Cells ◽  
Activin A ◽  
Pcr Analysis ◽  
Therapeutic Effects ◽  
Wild Type ◽  
Cd4 Cells ◽  
Activin Receptor ◽  
Tumor Bearing

BackgroundActivins, members of the transforming growth factor-ß (TGF-ß) superfamily, were isolated and identified in endocrine system, and have been widely studied in endocrine-related cancers,1 2 but not substantially in the context of immune system and endocrine-unrelated cancers.3–5 It has been reported that upon binding to the receptors, activins cause the intracellular recruitment and phosphorylation of smad proteins, which mediate the expression of Foxp3.6–9 Therefore, we hypothesized that the blockade of the interaction of activins and their receptors will inhibit the activins-mediated Foxp3 induction in CD4+ T cells, thus modify the immune suppressive tumor microenvironment and achieve the goal of cancer immunotherapy.MethodsELISA (enzyme-linked immunosorbent assay) has been performed to determine the plasma level of Activin A in tumor-bearing mice and cancer patients. In vitro iTreg (induced regulatory T cells) differentiation has been done to naïve CD4+ cells isolated from wild type mice in the presence or absence of Activin A, and the percentage of Foxp3+ cells was demonstrated by flow cytometric analysis. qRT-PCR analysis has been conducted to determine the mRNA level of activin receptor isotypes in the immune subpopulations sorted from Foxp3-YFP mice. In the end, in vivo subcutaneous transplanted tumor studies have been done to evaluate the anti-tumor therapeutic effects of activin-receptor 1c blockade.ResultsWe show here that tumor-bearing mice had elevated Activin A levels, which correlated directly with tumor burden. Likewise, cancer patients had elevated plasma Activin A compared to healthy controls. Importantly, our in vitro studies suggested that Activin A promoted differentiation of conventional CD4+ cells into Foxp3-expressing induced Tregs, especially when TGF-ß was limited. Database and qRT-PCR analysis of sorted major immune cell subsets in mice revealed that activin receptor 1C (Acvr1c) was uniquely expressed on Tregs and was highly upregulated during iTreg differentiation. Mice deficient in Acvr1c were more resistant to cancer progression compared to wild type mice. This phenotype correlated with reduced expression of the FoxP3 transcription factor in CD4+ cells. Similar phenomena were observed when we treated the mice with anti-Acvr1c antibody after tumor inoculation. This anti-tumor therapeutic effect was more significant when anti-Acvr1c antibody was administrated in combination with anti-PD-1 antibody.ConclusionsBlocking Activin A signaling through its receptor 1c is a promising and disease-specific strategy for preventing the accumulation of immunosuppressive iTregs in cancer. Hence it represents a potential candidate for cancer immunotherapy.AcknowledgementsThis research is supported by the Bloomberg-Kimmel Institute (Immunometabolism Program & Immune Modulation Program), the Melanoma Research Alliance, the NIH (RO1AI099300, RO1AI089830, and R01AI137046), and The DoD (PC130767).ReferencesRisbridger GP, Schmitt JF, Robertson DM. Activins and inhibins in endocrine and other tumors. Endocr Rev 2001;22(6):836–858.Cui X, et al. Perspectives of small molecule inhibitors of activin receptor-like kinase in anti-tumor treatment and stem cell differentiation (Review). Mol Med Rep 2019;19(6):5053–5062.Michael IP, et al. ALK7 signaling manifests a homeostatic tissue barrier that is abrogated during tumorigenesis and metastasis. Dev Cell 2019;49(3):409–424.Wu B, et al. The TGF-ß superfamily cytokine Activin-A is induced during autoimmune neuroinflammation and drives pathogenic Th17 cell differentiation. Immunity 2021;54(2):308–323.Antsiferova M, et al. Activin promotes skin carcinogenesis by attraction and reprogramming of macrophages. MBO Mol Med 2017;9(1):27–45.Tsuchida K, et al. Activin isoforms signal through type I receptor serine/threonine kinase ALK7. Mol Cell Endocrinol 2004;220(1–2):59–65.Khalil AM, et al. Differential binding activity of TGF-ß family proteins to select TGF-ß receptors. J Pharmacol Exp Ther 2016;358(3):423–430.Huber S, et al. Activin a promotes the TGF-beta-induced conversion of CD4+CD25- T cells into Foxp3+ induced regulatory T cells. J Immunol 2009;182(8):4633–4640.Iizuka-Koga M, et al. Induction and maintenance of regulatory T cells by transcription factors and epigenetic modifications. J Autoimmun 2017;83:113–121.Ethics ApprovalAll animal experiments were performed under protocols approved by the Johns Hopkins University Institutional Animal Care and Use Committee (IACUC).

scholarly journals Melatonin enhances porcine embryo development via the Nrf2/ARE signaling pathway

2019 ◽  
Vol 63 (3) ◽  
pp. 175-185 ◽  
Author(s):  
Eui Hyun Kim ◽  
Geon A Kim ◽  
Anukul Taweechaipaisankul ◽  
Seok Hee Lee ◽  
Muhammad Qasim ◽  
...  
Keyword(s):  
Embryonic Development ◽  
Signaling Pathway ◽  
Molecular Mechanisms ◽  
Antioxidant Properties ◽  
Specific Inhibitor ◽  
Treated Group ◽  
Related Factor ◽  
Porcine Embryo ◽  
Responsive Element

Oxidative stress (OS) is a major problem during in vitro culture of embryos. Numerous studies have shown that melatonin, which is known to have antioxidant properties, prevents the occurrence of OS in embryos. However, the molecular mechanisms by which melatonin prevents OS in embryos are still unclear. The present study suggests a possible involvement of the nuclear factor erythroid 2-related factor 2/antioxidant-responsive element (Nrf2/ARE) signaling pathway, which is one of the prominent signals for OS prevention through Nrf2 activation, connecting melatonin, OS prevention and porcine embryonic development. The aim of this study was to investigate the effects of melatonin (10−7 M) on porcine embryonic development via the Nrf2/ARE signaling pathway; brusatol (50 nM; Nrf2 specific inhibitor) was used to validate the mechanism. Treatment of porcine embryo with melatonin significantly increased formation rates of blastocysts and their total cell numbers and also upregulated the expression of Nrf2/ARE signaling and apoptosis-related genes (MT2, NRF2, UCHL, HO-1, SOD1 and BCL-2). Furthermore, the expression of proteins (NRF2 and MT2) was also upregulated in the melatonin-treated group. Concomitantly, brusatol significantly inhibited these effects, upregulating the expression of KEAP1 and BAX, including the expression level of KEAP1 protein. These results provide evidences that melatonin prevents OS through Nrf2/ARE signaling pathway in porcine in vitro fertilization -derived embryos.

scholarly journals A potent CBP/p300-Snail interaction inhibitor suppresses tumor growth and metastasis in wild-type p53-expressing cancer

2020 ◽  
Vol 6 (17) ◽  
pp. eaaw8500
Author(s):  
Hong-Mei Li ◽  
Yan-Ran Bi ◽  
Yang Li ◽  
Rong Fu ◽  
Wen-Cong Lv ◽  
...  
Keyword(s):  
Tumor Growth ◽  
Epithelial Mesenchymal Transition ◽  
Therapeutic Effects ◽  
Creb Binding Protein ◽  
Wild Type ◽  
Mesenchymal Transition ◽  
Patients With Cancer ◽  
Wild Type P53

The zinc finger transcription factor Snail is aberrantly activated in many human cancers and associated with poor prognosis. Therefore, targeting Snail is expected to exert therapeutic benefit in patients with cancer. However, Snail has traditionally been considered “undruggable,” and no effective pharmacological inhibitors have been identified. Here, we found a small-molecule compound CYD19 that forms a high-affinity interaction with the evolutionarily conserved arginine-174 pocket of Snail protein. In aggressive cancer cells, CYD19 binds to Snail and thus disrupts Snail’s interaction with CREB-binding protein (CBP)/p300, which consequently impairs CBP/p300-mediated Snail acetylation and then promotes its degradation through the ubiquitin-proteasome pathway. Moreover, CYD19 restores Snail-dependent repression of wild-type p53, thus reducing tumor growth and survival in vitro and in vivo. In addition, CYD19 reverses Snail-mediated epithelial-mesenchymal transition (EMT) and impairs EMT-associated tumor invasion and metastasis. Our findings demonstrate that pharmacologically targeting Snail by CYD19 may exert potent therapeutic effects in patients with cancer.

scholarly journals Peptide Deformylase in Staphylococcus aureus: Resistance to Inhibition Is Mediated by Mutations in the Formyltransferase Gene

2000 ◽  
Vol 44 (7) ◽  
pp. 1825-1831 ◽  
Author(s):  
Peter S. Margolis ◽  
Corinne J. Hackbarth ◽  
Dennis C. Young ◽  
Wen Wang ◽  
Dawn Chen ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Genomic Library ◽  
Specific Inhibitor ◽  
Peptide Deformylase ◽  
Cross Resistance ◽  
Loss Of Function ◽  
Wild Type ◽  
Chromosomal Dna ◽  
Resistant Mutants

ABSTRACT Peptide deformylase, a bacterial enzyme, represents a novel target for antibiotic discovery. Two deformylase homologs, defA and defB, were identified inStaphylococcus aureus. The defA homolog, located upstream of the transformylase gene, was identified by genomic analysis and was cloned from chromosomal DNA by PCR. A distinct homolog, defB, was cloned from an S. aureus genomic library by complementation of the arabinose-dependent phenotype of a P BAD -def Escherichia coli strain grown under arabinose-limiting conditions. Overexpression in E. coli of defB, but not defA, correlated to increased deformylase activity and decreased susceptibility to actinonin, a deformylase-specific inhibitor. ThedefB gene could not be disrupted in wild-type S. aureus, suggesting that this gene, which encodes a functional deformylase, is essential. In contrast, thedefA gene could be inactivated; the function of this gene is unknown. Actinonin-resistant mutants grew slowly in vitro and did not show cross-resistance to other classes of antibiotics. When compared to the parent, an actinonin-resistant strain produced an attenuated infection in a murine abscess model, indicating that this strain also has a growth disadvantage in vivo. Sequence analysis of the actinonin-resistant mutants revealed that each harbors a loss-of-function mutation in the fmt gene. Susceptibility to actinonin was restored when the wild-type fmt gene was introduced into these mutant strains. An S. aureusΔfmt strain was also resistant to actinonin, suggesting that a functional deformylase activity is not required in a strain that lacks formyltransferase activity. Accordingly, thedefB gene could be disrupted in an fmt mutant.

scholarly journals NLRP3 Inflammasome Activation Attenuates Neuronal Apoptosis by Upregulating Autophagy through AMPK/Beclin-1 Pathway after Intracerebral Hemorrhage with Ventricular Extension in Rats

2021 ◽  
Author(s):  
Zhaoqi Zhang ◽  
Peiwen Guo ◽  
Zhengcai Jia ◽  
Tunan Chen ◽  
Hua Feng
Keyword(s):  
Intracerebral Hemorrhage ◽  
Nlrp3 Inflammasome ◽  
Neuronal Apoptosis ◽  
Specific Inhibitor ◽  
Beclin 1 ◽  
Tunel Staining ◽  
Inflammasome Activation ◽  
Sprague Dawley

Abstract BackgroundIn brain, NLRP3 inflammasome, mainly derived from macrophage/microglia, is involved in proinflammatory and neurodeficits after hemorrhage, and autophagy is vital for neuronal homeostasis and functions. Accumulating evidence suggested that NLRP3 inflammasome and autophagy played an important role in intracerebral hemorrhage (ICH). Thus, this study was designed to further explore the pathogenesis of neurodeficits after in posthemorrhagic hydrocephalus.MethodsAutologous blood injection model was induced to mimic ICH with ventricular extension (ICH-IVH) in Sprague-Dawley rats. To elucidate the underlying mechanism, the NLRP3 inflammasome inhibitor MCC950 was administered abdominally at 1 h after ICH-IVH. Magnetic resonance imaging, neurobehavioral tests, immunofluorescence, western blotting, Fluoro-Jade C- staining, Tunel staining, and Quantitative RNA Sequencing were performed.ResultsIn the acute phase of ICH-IVH, both the expression of NLRP3 inflammasome and the autophagy of neurons were upregulated. The activated NLRP3 in macrophage/microglia promoted the release of IL-1β to extracellular, which contributed to excessive autophagy, leading to neurons apoptosis both in vivo and in vitro. AMPK/Beclin-1 pathway played an important role in NLRP3-related neurons autophagy. Using MCC950(NLRP3 inflammasome specific inhibitor) treatment after ICH-IVH significantly reduced ventricles dilation, improved neurofunction, down-regulated the release of IL-1β, and alleviated neuroinflammation and excessive autophagy.ConclusionsOur finding demonstrated that NLRP3 inflammasome activated in microglia/macrophage aggravated neurological outcomes and neuronal apoptosis by upregulating autophagy after ICH-IVH, which was partly mediated by the AMPK/Beclin-1 pathway. Therefore, inhibiting the activation of NLRP3 may be a potential therapeutic strategy for the neurodeficits of ICH-IVH patients.

scholarly journals The Interleukin-17 Gene of Herpesvirus Saimiri

1998 ◽  
Vol 72 (7) ◽  
pp. 5797-5801 ◽  
Author(s):  
Andrea Knappe ◽  
Christian Hiller ◽  
Henk Niphuis ◽  
François Fossiez ◽  
Mathias Thurau ◽  
...  
Keyword(s):  
T Cell ◽  
Cell Transformation ◽  
Cell Lymphoma ◽  
Gene Knockout ◽  
Herpesvirus Saimiri ◽  
Interleukin 17 ◽  
Wild Type ◽  
Knockout Mutants ◽  
Cottontop Tamarins

ABSTRACT In comparison to wild-type herpesvirus saimiri, viral interleukin-17 gene knockout mutants have unaltered behavior regarding viral replication, T-cell transformation in vitro, and pathogenicity in cottontop tamarins. Thus, this gene is not required for T-cell lymphoma induction but may contribute to apathogenic viral persistence in the natural host, the squirrel monkey.

Validating targets for antiparasite chemotherapy

Parasitology ◽  
1997 ◽  
Vol 114 (7) ◽  
pp. 31-44 ◽  
Author(s):  
C. C. WANG
Keyword(s):  
Drug Targets ◽  
Drug Transport ◽  
Gene Knockout ◽  
Specific Inhibitor ◽  
Selective Inhibition ◽  
Conclusive Evidence ◽  
Gene Encoding ◽  
Multiple Copies ◽  
Antiparasitic Agents

The enzymes and receptors in parasites that can be qualified as targets for antiparasite chemotherapy should perform essential functions in the parasites and demonstrate some feasibility for selective inhibition. They can be tentatively identified through detailed analysis of various aspects of metabolisms in the parasites or elucidation of the mechanisms of action among proven antiparasitic agents. Preliminary verifications of these putative targets can be indicated by in vitro antiparasite activity of an inhibitor of the target. However, before a major long-term effort to pursue in-depth structure-activity analysis of the target is to be committed for specific inhibitor design, further validations of the target are essential to insure that future studies are not misguided. One old-fashioned approach to validate a target in the pharmaceutical industry is by correlating target inhibitions with antiparasitic activities among large numbers of drug derivatives. The results are often indicative but hardly ever conclusive. Another method is by comparing the putative drug targets between the drug-sensitive and the drug-resistant parasites for potential discrepancies. Unfortunately, the latter often result from indirect causes, such as reduced drug transport, instead of an alteration of the drug target itself. The third experimental approach is by disrupting the gene encoding the putative target in parasite, which can provide the most conclusive evidence on whether the target plays an indispensible role in the parasite. But special conditions are needed for the gene knockout mutants to survive to exhibit their phenotypes and to allow genetic complementation studies for further verifications. Furthermore, gene knockout experiments are often difficult to perform on cells of multiple ploidy or genes of multiple copies, and are currently applicable only to a limited number of protozoan parasites. In the current article I have tried to take a cursory look at some eleven putative drug targets among various parasites, each supported by well-established antiparasitic agents identified as its inhibitors. I have also considered the evidence for validity of each of them and the potential means of further verifying their validity.

scholarly journals Interneuron Transplantation Creates New Network States and Rescues Social Behavior Deficits in a Mouse Model of Autism

Neurosurgery ◽  
2019 ◽  
Vol 66 (Supplement_1) ◽  
Author(s):  
Derek Southwell ◽  
Helia Seifikar ◽  
Ruchi Malik ◽  
Karen Lavi ◽  
Daniel Vogt ◽  
...  
Keyword(s):  
Social Behavior ◽  
Neuropsychiatric Disorders ◽  
Inhibitory Interneuron ◽  
Network Activity ◽  
Therapeutic Effects ◽  
Synaptic Inhibition ◽  
Behavioral State ◽  
Wild Type

Abstract INTRODUCTION Inhibitory interneuron transplantation is a prospective treatment for neuropsychiatric disorders, but it is unclear whether transplantation might elicit therapeutic effects by reversing preexisting abnormalities, nonspecifically increasing synaptic inhibition, or engaging mechanisms that vary depending on recipient background and behavioral state. METHODS We transplanted wild-type embryonic interneuron precursors into mice lacking an autism-associated gene, Pten, in inhibitory interneurons. Additionally, we performed transplantation into wild-type recipient mice, and then examined the recipient behavior, cellular physiology in Vitro, and network physiology in Vivo. RESULTS Transplantation rescued social behavior deficits in Pten mutants without normalizing excessive synaptic inhibition in Vitro or reduced baseline gamma oscillatory power in Vivo. However, transplantation altered recipient electroencephalography (EEG) responses observed specifically during periods of social interaction. When transplantation was performed into wild-type recipients, the subtype composition of the transplanted population varied from that observed in Pten mutants, and, moreover, recipients did not exhibit alterations to social behavior or related EEG responses. CONCLUSION Interneuron transplantation elicits recipient- and behavioral state-dependent effects, and normalizes behavior by creating new patterns of network activity, rather than restoring wild-type states. Interneuron transplantation may provide a novel therapeutic approach to the treatment of autism and related neuropsychiatric disorders.

scholarly journals Specific NDM-1 Inhibitor of Isoliquiritin Enhances the Activity of Meropenem against NDM-1-positive Enterobacteriaceae in vitro

2020 ◽  
Vol 17 (6) ◽  
pp. 2162
Author(s):  
Yanling Wang ◽  
Xiaodi Sun ◽  
Fanrong Kong ◽  
Lining Xia ◽  
Xuming Deng ◽  
...  
Keyword(s):  
Antibacterial Effect ◽  
Specific Inhibitor ◽  
Inhibitory Effect ◽  
Therapeutic Effects ◽  
New Delhi ◽  
E Coli ◽  
Class B ◽  
Time Kill ◽  
Growth Of Bacteria

NDM-1-positive Enterobacteriaceae have caused serious clinical infections, with high mortality rates. Carbapenem was the ultimate expectation for the treatment of such infections in clinical practice. However, since the discovery of plasmid-mediated New Delhi metallo-β-lactamase-1 (NDM-1), the efficient therapeutic effects of carbapenems have been increasingly restricted. Here, we identified isoliquiritin, a novel specific inhibitor of the NDM-1 enzyme that restored the activity of carbapenem against NDM-1-producing E. coli isolates and K. pneumoniae isolates without affecting the growth of bacteria. A checkerboard test, growth curve assays and time-kill assays confirmed the significant synergistic effect of isoliquiritin combined with meropenem in vitro. It is worth noting that isoliquiritin only inhibited the activity of NDM-1 and had no obvious inhibitory effect on other class B metallo-β-lactamases (VIM-1) or NDM-1 mutants (NDM-5). The FIC indices of meropenem with isoliquiritin on NDM-1-positive E. coli and K. pneumoniae were all less than 0.5. Isoliquiritin had no influences on the expression of NDM-1-positive strains at concentrations below 64 µg/mL. Collectively, our results show that isoliquiritin is a potential adjuvant therapy drug that could enhance the antibacterial effect of carbapenems, such as meropenem, on NDM-1-positive Enterobacteria and lay the foundation for subsequent clinical trials.

Adiponectin inhibits palmitic acid-induced NLRP3 inflammasome activation in hepatocytes through AMPK-JNK/ErK1/2-NFκB/ROS signaling pathways

2020 ◽  
Author(s):  
Zhixia Dong ◽  
Qian Zhuang ◽  
Xin Ye ◽  
Min Ning ◽  
Shan Wu ◽  
...  
Keyword(s):  
Protein Expression ◽  
Palmitic Acid ◽  
Signaling Pathways ◽  
Nlrp3 Inflammasome ◽  
Inflammasome Activation ◽  
Ros Production ◽  
Wild Type ◽  
Nlrp3 Inflammasome Activation

Abstract Background Adiponectin, an adipose-derived adipokine, possesses a hepatoprotective role in various liver disorders. Inflammasome activation has been recognized to play a major role during the progression of non-alcoholic fatty liver diseases (NAFLD). However, the effect of adiponectin on NLRP3 inflammasome activation in liver and the exact mechanism remains largely unclear. Here, we assessed the effect of adiponectin on NLRP3 inflammasome activation and its potential molecular mechanisms through both in vivo and in vitro experiments. Methods Male adiponectin-knockout (adiponectin-KO) mice and C57BL/6 (wild-type) mice were fed a high-fat-diet (HFD) for 12 weeks as an in vivo model of non-alcoholic steatohepatitis (NASH). Serum biochemical markers, liver histology and inflammasome-related gene and protein expression were determined. In addition, the hepatocytes isolated from SD rats were exposed to palmitic acid(PA) in the absence or presence of adiponectin and/or AMPK inhibitor. The activation of NLRP3 inflammasome was assessed by mRNA and protein expression. Furthermore, ROS production and related signaling pathways were also evaluated. Results In the in vivo experiments, we found that adiponectin deficiency mice fed with HFD presented excessive hepatic steatosis with increased NLRP3 inflammasome activation compared to wild-type mice. Moreover, the expression levels of NLRP3 inflammasome activation pathway molecules (NFκB and ROS) were upregulated, while the phosphorylation levels of AMPK, JNK and Erk1/2 were downregulated in adiponectin-knockout mice compared with wild-type mice. In the in vitro study, PA significantly promoted NLRP3 inflammasome activation in hepatocytes. Additionally, PA increased lipid droplet deposition, NF-kB signaling and ROS production, while adiponectin could abolish PA-mediated NLRP3 inflammasome activation and decrease ROS production, which was reversed by AMPK inhibitor (compound C). The results indicated that the inhibitory effect of adiponectin on PA-mediated NLRP3 inflammasome activation was regulated by AMPK-JNK/ErK1/2-NFκB/ROS signaling pathway. Conclusion Adiponectin inhibited PA-mediated NLRP3 inflammasome activation in hepatocytes. Adiponectin analogs or AMPK agonists could serve as a potential novel agent for preventing or delaying the progression of NASH and NAFLD.

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