NLR Family Pyrin Domain Containing 3 Research Articles

Astragaloside IV attenuates podocyte apoptosis via regulating TXNIP/NLRP3/GSDMD signaling pathway in diabetic nephropathy

ObjectivesAmong all the diabetes complications brought on by persistent inflammation is diabetic kidney disease (DKD). One essential method of the inflammatory response's programmed cell death is anthrax. One of the main causes of diabetic renal disease progression in a high-glycemic environment is the lysis of renal resident cells.MethodThis investigation sought to determine whether Astragaloside IV (AS-IV)'s anti-pyroptosis action provides a protective function for the kidneys. For 12 weeks, db/db mice received 40 mg/kg of AS-IV by transgastric gavage. To validate the possible in vitro mechanism, mouse podocytes were cultivated for additional experiments.ResultsIn vitro, AS-IV led to a significant reduction in blood urea nitrogen (BUN), urine albumen-to-creatinine ratio (UACR), serum creatinine (CREA), and hyperglycemia in db/db mice and lessen the pathological alterations in the kidney. Moreover, pyrin structural domain of the NLR family pyrin domain containing 3 (NLRP3), cleaved-caspase-1, gasdermin D (GSDMD), IL-18, and IL-1β were down-expressed and podocyte markers podocin and nphs1 were up-regulated following AS-IV intervention. By silencing GSDMD, we demonstrated in vitro that HG-stimulated podocytes undergo pyroptosis. We also discovered that AS-IV can mitigate this pyroptosis. To confirm that AS-IV prevented the NLRP3 inflammasome from activating, the NLRP3 inhibitor CY-09 was employed. It was also discovered that AS-IV prevents the expression of TXNIP and NLRP3 as well as their interaction. GSDMD expression was significantly downregulated following TXNIP-siRNA treatment, whereas GSDMD expression was upregulated in TXNIP overexpression cells; this upregulation could be undone with AS-IV.ConclusionsThe anti-pyroptosis effect of AS-IV via the TXNIP-NLRP3-GSDMD axis improves the renal function and podocyte damage of db/db mice and delays the onset of DKD, according to in vivo and in vitro experimental data.

The role of inflammasome dysregulation in obstructive and non-obstructive azoospermia: a comparative molecular analysis of blood, tissue, and seminal plasma

BackgroundTo address knowledge gaps, this study aimed to investigate the involvement of inflammasomes in the etiology of azoospermia. This study focused on the gene expression of key inflammasome components, including NLR family pyrin domain containing 3 (NLRP-3), CASPASE-1, Interleukin-1β (IL-1β), Interleukin-18 (IL-18), NLR family CARD domain-containing protein 4/ice protease-activating factor (NLRC-4/IPAF), and Absent in melanoma 2 (AIM-2).MethodsWe analyzed gene expression in blood and testicular tissue from patients with obstructive azoospermia (OA) and non-obstructive azoospermia (NOA). Additionally, we compared IL-1β and IL-18 expression levels in seminal plasma samples using the Enzyme-Linked Immunosorbent Assay (ELISA) method. For comparison, blood samples from normospermic (NS) individuals were also genetically evaluated.ResultsOur results indicated significantly higher gene expression of inflammasome components in NOA patients than those in OA patients either in blood or in testicular tissue. Both azoospermic groups exhibited higher mRNA levels of inflammasome genes comparing with those from blood samples of NS men. Seminal plasma samples showed significantly increased levels of IL-1β and IL-18 in NOA patients compared to men with OA. The ROC curve analysis indicated strong and significant predictive power of IL-18, AIM-2 and NLRC-4/IPAF gene expression profiles between NOA vs. NS patients and NOA vs. OA.ConclusionsOur findings highlight the role of hidden chronic inflammation in azoospermia, particularly within the NOA group. This study provides a foundation for further detailed research, which could aid in the development of diagnostic panels to differentiate between various azoospermic groups.

NOD3 Reduces Sepsis-Induced Acute Lung Injury by Regulating the Activation of NLRP3 Inflammasome and the Polarization of Alveolar Macrophages.

The pathogenesis of sepsis-induced Acute lung injury (ALI) progresses rapidly, and no effective treatment drugs are known, resulting in a high mortality rate. NLR family pyrin domain containing 3 (NLRP3) inflammasome activation plays an important role in the pathological progression of ALI, and often coincide with the inflammatory activation and polarization of macrophages. NLR family CARD domain-containing protein 3 (NOD3) was reported protecting against sepsis-induced pulmonary pathological injury and inhibiting the inflammatory response in lung tissue. NOD3 can also inhibit NLRP3 inflammasome activation by competitively inhibiting the binding of pro-caspase-1 to apoptosis-related ASC or reducing NLRP3/cryopyrin-induced ASC speckle formation. In this study, we aimed to explore whether NOD3 decrease sepsis-induced lung injury by interfering with NLRP3 inflammasome activation and regulating alveolar macrophages (AMs) polarization. To investigate whether NOD3 reduce sepsis-induced ALI by inhibiting the activation of NLRP3 inflammasome to regulate the polarization of AMs. Sepsis-induced WT (C57BL/6) and NLRC3-/--C57BL/6 mice ALI models were established by intraperitoneal injection of lipopolysaccharide (LPS). In vitro experiments, AMs and bone marrow-derived macrophages (BMDMs) were isolated from WT and NLRC3-/- mice. Using in vivo and in vitro experiments, we found that NOD3 knockout promoted the sepsis-induced inflammatory response in lung tissue. In addition, NOD3 knockout promoted the activation of the TRAF6-NF-κB signaling pathway and the NLRP3 inflammasome in AMs, enhanced the M1-type polarization of AMs and decreased the M2-type polarization of AMs in sepsis-induced lung injury model mice. NOD3 interfered with NLRP3 inflammasome activation by inhibiting NLRP3 inflammasome assembly or negatively regulating the TRAF6-NF-κB signaling pathway, and regulating the polarization of AMs, thereby alleviating sepsis-induced lung injury.

Iodine activates NLRP3 inflammasomesin PBMCs of patients with autoimmune thyroiditis, and regulates Th1 and Th17 cell differentiation.

Inflammasomes are associated with various autoimmune diseases. Herein, we aimed to study the occurrence of inflammasomes in peripheral blood mononuclear cells (PBMCs) from patients with autoimmune thyroiditis (AIT), and the relationship between their abundance and the inflammatory response index of AIT. Furthermore, we examined the effect of iodine on inflammasomes containing NLR family pyrin domain containing 3 (NLRP3) and inflammasome activation of helper T cell (Th) differentiation regulation in cultured PBMCs.

Telomerase RNA component knockout exacerbates Staphylococcus aureus pneumonia by extensive inflammation and dysfunction of T cells.

The telomerase RNA component (Terc) constitutes a non-coding RNA critical for telomerase function, commonly associated with aging and pivotal in immunomodulation during inflammation. Our study unveils heightened susceptibility to pneumonia caused by Staphylococcus aureus (S. aureus) in Terc knockout (Tercko/ko) mice compared to both young and old infected counterparts. The exacerbated infection in Tercko/ko mice correlates with heightened inflammation, manifested by elevated interleukin-1β (IL-1β) levels and activation of the NLR family pyrin domain containing 3 (NLRP3) inflammasome within the lung. Employing mRNA sequencing methods alongside in vitro analysis of alveolar macrophages (AMs) and T cells, our study elucidates a compelling correlation between Tercko/ko, inflammation, and impaired T cell functionality. Terc deletion results in compromised T cell function, characterized by dysregulation of the T cell receptor and absence of CD247, potentially compromising the host's capacity to mount an effective immune response against S. aureus. This investigation provides insights into the intricate mechanisms governing increased vulnerability to severe pneumonia in the context of Terc deficiency, which might also contribute to aging-related pathologies, while also highlighting the influence of Terc on T cell function.

Intranasal dantrolene nanoparticles inhibit inflammatory pyroptosis in 5XFAD mice brains.

This study investigates the effects of intranasal dantrolene nanoparticles on inflammation and programmed cell death by pyroptosis in 5XFAD Alzheimer's Disease (AD) mice. 5XFAD and wild type (WT) B6SJLF1/J mice were treated with intranasal dantrolene nanoparticles (5 mg/kg), daily, Monday to Friday, for 12 weeks continuously, starting at 9 months of age. Blood and brain were harvested at 13 months of age, one month after completion of 12 weeks intranasal dantrolene nanoparticle treatment. Blood biomarkers function of liver (Alanine transaminase, ALT), kidney (Creatinine), and thyroid (TSH: Thyroid-stimulating hormone) were measured using ELISA. The changes of whole brain tissue proteins on Ca 2+ release channels on membrane of endoplasmic reticulum (type 2 ryanodine and type 1 InsP3 receptors, RyR-2 and InsP3R-1), lipid peroxidation byproduct malondialdehyde (MDA)-modified proteins, 4-HNE, pyroptosis regulatory proteins (NLR family pyrin domain containing 3 (NLRP3), cleaved caspase-1, full length or N-terminal of Gasdermin D (GSDMD), cytotoxic (IL-1, IL-18, IL-6, TNF-a) and cytoprotective (IL-10) cytokines, astrogliosis (GFAP), microgliosis (IBA-1) and synapse proteins (PSD-95, Synapsin-1) were determined using immunoblotting. Body weights were monitored regularly. Intranasal dantrolene nanoparticles significantly inhibited the increase of RyR-2 and InsP3R-1 proteins, MDA-modified proteins, 4-NHE, pyroptosis regulatory proteins (NLRP3, cleaved caspase-1, N-terminal GSDMD), cytotoxic cytokine (IL-1β, IL-18, IL-6, TNF-α), biomarkers for astrogliosis (GFAP) and microgliosis (IBA-1), and the decrease of cytoprotective cytokine (IL-10) and synaptic proteins (PSD-95, synpasin-1). Intranasal dantrolene nanoparticles for 12 weeks did not affect blood biomarkers for function of liver, kidney, and thyroid, not did it change body weight significantly. Intranasal dantrolene nanoparticles significantly inhibit the increase of RyR-2 and InsP 3 R-1 Ca 2+ channel receptor proteins, ameliorate activation of the pyroptosis pathway and pathological inflammation, and the associated loss of synapse proteins. Intranasal dantrolene nanoparticles for three months did not affect liver, kidney and thyroid functions or cause other side effects.

MALAT1 promotes colonic epithelial cell apoptosis and pyroptosis by sponging miR-22-3p to enhance NLRP3 expression.

Colonic epithelial cell apoptosis and pyroptosis had a close relationship with the pathological progression of ulcerative colitis (UC). LncRNA play a crucial role in the progression of UC. However, the role of the lncRNA MALAT1 in colonic epithelial cell apoptosis and pyroptosis remains unclear. UC colitis cell model was established through lipopolysaccharide (LPS) treatment. MiR-22-3p and MALAT1 expression in fetal human colon (FHC) cells were analyzed by qRT-PCR. Proliferation and apoptosis of FHCs were measured using CCK-8 assay and flow cytometry, respectively. Pyroptosis indicators including interleukin (IL)-1β, IL-18, tumor necrosis factor-α (TNF-α), NLR family pyrin domain containing 3 (NLRP3), caspase-1, and N-gasdermin D (N-GSDMD) in FHCs were detected using ELISA, qRT-PCR, western blotting, and immunofluorescence. In this study, apoptosis was facilitated, IL-1β, IL-18, and TNF-α levels were enhanced, NLRP3, caspase-1, N-GSDMD protein were increased, and MALAT1 expression was markedly increased in LPS-treated FHCs (LTFs). MALAT1 knockdown remarkably facilitated proliferation and suppressed apoptosis, reduced IL-1β, IL-18, and TNF-α levels, and decreased the protein of NLRP3, caspase-1, N-GSDMD. Furthermore, NLRP3 overexpression remarkably reversed the effect of MALAT1-downexpression in LTFs. In addition, miR-22-3p could bind with MALAT1 and NLRP3 3' UTR. Furthermore, miR-22-3p inhibition remarkably reversed the effect of MALAT1 overexpression in LTFs. These findings suggest that MALAT1 represents a promising therapeutic target for the treatment of UC by modulating the miR-22-3p/NLRP3 pathway, potentially leading to novel strategies for reducing inflammation and cell death in the colon.

Understanding the Role of NLRP3 Inflammasome in Acute Pancreatitis.

Acute pancreatitis (AP) remains a serious clinical condition, with current treatment options being largely supportive. The discovery of inflammasomes, particularly the NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, has significantly advanced our knowledge regarding many inflammatory diseases' pathogenesis, including AP. The NLRP3 inflammasome is central in mediating the inflammatory process in AP through its diverse activation mechanisms and its involvement in multiple signal transduction pathways. This has made NLRP3 an appealing target for novel therapeutic strategies aimed at modulating inflammation in AP. Despite the growing interest in NLRP3 as a therapeutic target, there remains a notable gap in clinical research, with few clinical trials exploring the efficacy of NLRP3 inhibitors in AP. Results of several preclinical studies and animal models are promising and suggest that the use of NLRP3 inhibitors could result in reduced inflammation and improved patient outcomes in AP. Further research is urgently needed to assess their potential benefits, safety, and applicability in human patients and address the underlying inflammatory processes driving AP.

Mesenchymal Stem Cell-Derived Extracellular Vesicles Carrying Circ-Tulp4 Attenuate Diabetes Mellitus with Nonalcoholic Fatty Liver Disease by Inhibiting Cell Pyroptosis through the HNRNPC/ABHD6 Axis.

Diabetes mellitus with nonalcoholic fatty liver disease (DM-NAFLD) represents a complex metabolic syndrome with significant clinical challenges. This study explores the therapeutic potential and underlying mechanisms of umbilical cord-derived mesenchymal stem cells (UCMSCs)-derived extracellular vesicles (EVs) in DM-NAFLD. UCMSCs-EVs were isolated and characterized. DM-NAFLD mouse model was developed through high-energy diet and streptozotocin injection. Additionally, primary mouse hepatocytes were exposed to high glucose to simulate cellular conditions. Hepatic tissue damage, body weight changes, lipid levels, glucose and insulin homeostasis, and hepatic lipid accumulation were evaluated. The interaction between UCMSCs-EVs and hepatocytes was assessed, focusing on the localization and function of circ-Tulp4. The study also investigated the expression of circularRNA TUB-like protein 4 (circ-Tulp4), heterogeneous nuclear ribonucleoprotein C (HNRNPC), abhydrolase domain containing 6 (ABHD6), cleaved Caspase-1, NLR family pyrin domain containing 3 (NLRP3) and cleaved N-terminal gasdermin D (GSDMD-N). The binding of circ-Tulp4 to lysine demethylase 6B (KDM6B) and the subsequent epigenetic regulation of ABHD6 by H3K27me3 were analyzed. Circ-Tulp4 was reduced, while HNRNPC and ABHD6 were elevated in DM-NAFLD models. UCMSCs-EVs attenuated hepatic steatosis and inhibited the NLRP3/cleaved Caspase-1/GSDMD-N pathway. EVs delivered circ-Tulp4 into hepatocytes, thereby restoring circ-Tulp4 expression. Elevated circ-Tulp4 enhanced the recruitment of H3K27me3 to the HNRNPC promoter through interaction with KDM6B, thus suppressing HNRNPC and ABHD6. Overexpression of HNRNPC or ABHD6 counteracted the protective effects of UCMSCs-EVs, exacerbating pyroptosis and hepatic steatosis in DM-NAFLD. UCMSCs-EVs deliver circ-Tulp4 into hepatocytes, where circ-Tulp4 inhibits the HNRNPC/ABHD6 axis, thereby reducing pyroptosis and alleviating DM-NAFLD. These findings provide a novel therapeutic avenue for targeting DM-NAFLD through modulation of cell pyroptosis.

Diosmin alleviates NLRP3 inflammasome-dependent cellular pyroptosis after stroke through RSK2/CREB pathway

In the context of our previous analyses on the main active ingredients of Jieyudan, a classic formula targeting aphasia in stroke, we further delve into the function and mechanisms of its active ingredient, Diosmin (DM), which may exert neuroprotective effects, in ischemic stroke. Herein, bioinformatics analysis revealed targets of DM and their intersection with differentially expressed genes in ischemic stroke. Middle cerebral artery occlusion (MCAO) rats and oxygen-glucose deprivation (OGD) cells were used to construct in vivo and in vitro models of ischemic stroke. The effects of DM on MCAO rats were assessed by Zea-Longa score, Morris water maze, TTC staining, Nissl staining, immunohistochemistry, and Western blot. At the cellular level, cell counting kit-8 assay and Western blot were carried out to verify the mechanism of DM in ischemic stroke. In vivo, DM decreased neurological deficit score, cerebral infarct volume and neuronal damage, and improved cognitive function in MCAO rats. In vitro, DM increased the viability of OGD-treated cells. In addition, DM down-regulated the expressions of NLR family pyrin domain containing 3 (NLRP3) and pyroptosis-associated proteins, while up-regulating ribosomal protein S6 kinase A3 (RSK2) level and activating cyclic-AMP response element-binding protein (CREB) signaling. Conversely, RSK2 inhibitor LJH685 reduced the viability and promoted pyroptosis-associated protein levels, which also partially reversed the effects of DM in vitro. Collectively, DM plays a therapeutic role in ischemic stroke by inhibiting NLRP3 inflammasome-mediated cellular pyroptosis via the RSK2/CREB pathway.

Taraxerone inhibits M1 polarization and alleviates sepsis-induced acute lung injury by activating SIRT1

BackgroundAcute lung injury (ALI) is the most lethal disease associated with sepsis, and there is a lack of effective drug treatment. As the major cells of sepsis-induced ALI, macrophages polarize toward the proinflammatory M1 phenotype and secrete multiple inflammatory cytokines to accelerate the disease process through nuclear factor kappa-B (NF-κB) and NLR family pyrin domain containing 3 (NLRP3) inflammasome signaling pathways. Taraxerone, the main component of the Chinese medicinal Sedum, possesses numerous biological activities. However, uncertainty remains regarding the potential of taraxerone to protect against sepsis-induced ALI. This study aimed to investigate the effects and mechanisms of taraxerone against ALI.MethodsAn animal model for ALI was established by cecal ligation and puncture and treated with taraxerone via intraperitoneal administration. The protective effect of taraxerone on the lungs was analyzed using H&E staining, dihydroethidium staining, ELISA kits, cell counting, myeloperoxidase kit, malondialdehyde kit, glutathione kit, superoxide dismutase kit and flow cytometry. Western blotting, RT-PCR, flow cytometry, co-immunoprecipitation, and immunofluorescence were used to investigate the regulatory of taraxerone on SIRT1.ResultsOur study demonstrates for the first time that taraxerone can activate SIRT1 in macrophages, promoting SIRT1 activity. This activation inhibited the NF-κB signaling pathway primarily through the dephosphorylation and deacetylation of p65. Simultaneously, taraxerone disrupted the NLRP3 inflammasome signaling pathway, thereby alleviating M1 polarization of macrophages and mitigating sepsis-induced pulmonary inflammation and oxidative stress. In vivo, EX527 was used to validate the anti-inflammatory and anti-oxidative stress effects of taraxerone mediated by SIRT1.ConclusionSIRT1-mediated anti-inflammatory and anti-oxidative stress effects may be important targets for taraxerone in treating ALI.

Oxidative stress and mitochondrial dysfunction contributes to postoperative cognitive dysfunction in elderly rats dependent on NLRP3 activation.

Postoperative cognitive dysfunction (POCD), a complication following procedures such as orthopedic surgery, is associated with a worsened prognosis, especially in the elderly population. Several mechanisms have been proposedfor communication between the immune system and the brain after surgery. In an experimental tibial fracture (TF) model, we aimed to understand the role of the NLR family pyrin domain containing 3 (NLRP3) on oxidative stress and mitochondrial dysfunction as mechanisms underlying POCD in aged and adult rats.Adult or aged male Wistar rats were subjected to the TF model and receivedintracerebroventricularsaline or MCC950 (140ng/kg), a specific small-molecule inhibitor that selectively blocks activation of the NLRP3 inflammasome.We followed the control (sham) and TF groups treated with MCC950 or saline for seven days to determine cognitive function and survival.The prefrontal cortex and hippocampus were isolated for NLRP3 evaluation, cytokine analysis, oxidative stress measurements, myeloperoxidase activity, nitric oxide formation, mitochondrial respiratory chain enzymes, and succinate dehydrogenase (SDH) activity. Seven days after TF induction, NLRP3 levels increased in the hippocampus and prefrontal cortex in both ages, showed an enhancement in aged rats compared to adults, and experienced a reversal with MCC950 administration.The administration of MCC950 restored memory, IL-1β and IL-10 levels, nitrite/nitrate, lipid peroxidation in the hippocampus and prefrontal cortex, and preserved catalase activity in the prefrontal cortex in aged rats. At the same age, the complex I activity alteration in both regions and complex II, IV, and SDH in the prefrontal cortex werereversed. In conclusion, NLRP3 activation contributes to POCD development because it is intrinsically involved in mitochondrial dysfunction and oxidative stress after orthopedic surgery in aged rats.

PINK1-deficiency facilitates mitochondrial iron accumulation and colon tumorigenesis

ABSTRACT Mitophagy, the process by which cells eliminate damaged mitochondria, is mediated by PINK1 (PTEN induced kinase 1). Our recent research indicates that PINK1 functions as a tumor suppressor in colorectal cancer by regulating cellular metabolism. Interestingly, PINK1 ablation activated the NLRP3 (NLR family pyrin domain containing 3) inflammasome, releasing IL1B (interleukin 1 beta). However, inhibiting the NLRP3-IL1B signaling pathway with an IL1R (interleukin 1 receptor) antagonist or NLRP3 inhibitor did not hinder colon tumor growth after PINK1 loss. To identify druggable targets in PINK1-deficient tumors, ribonucleic acid sequencing analysis was performed on colon tumors from pink1 knockout and wild-type mice. Gene Set Enrichment Analysis highlighted the enrichment of iron ion transmembrane transporter activity. Subsequent qualitative polymerase chain reaction and western blot analysis revealed an increase in mitochondrial iron transporters, including mitochondrial calcium uniporter, in PINK1-deficient colon tumor cells and tissues. Live-cell iron staining demonstrated elevated cellular and mitochondrial iron levels in PINK1-deficient cells. Clinically used drugs deferiprone and minocycline reduced mitochondrial iron and superoxide levels, resulting in decreased colon tumor cell growth in vitro and in vivo. Manipulating the mitochondrial iron uptake protein MCU (mitochondrial calcium uniporter) also affected cell and xenograft tumor growth. This study suggests that therapies aimed at reducing mitochondrial iron levels may effectively inhibit colon tumor growth, particularly in patients with low PINK1 expression.

Deficiency of muscle-generated brain-derived neurotrophic factor causes inflammatory myopathy through reactive oxygen species-mediated necroptosis and pyroptosis

Idiopathic inflammatory myopathy (commonly known as myositis) is a group of immune-related diseases characterized by muscle damage, weakness, and fatigue with unknown causes. Although overactivated innate immunity is a widely believed cause of myositis onset, the mechanism that provokes and maintains a high immune response in myositis patients is still unclear. This study aims to test if brain-derived neurotrophic factor (BDNF) deficiency per se is sufficient to cause myositis and determine its underlying mechanism. We found that ablating BDNF production in skeletal muscle is sufficient to trigger myositis development in mice. Muscle-specific Bdnf knockout (MBKO) mice displayed extensive myocyte necrosis, mononuclear cell infiltration, and myophagocytosis. In association with these damages, elevated production of pro-inflammatory cytokines such as interleukin (IL) 23, IL-1β, IL-18, and tumor necrosis factor α (TNFα) was found in the muscle of MBKO mice. Disruption of sarcolemma integrity was also detected in MBKO mice, which is a result of necroptosis executioner Mixed lineage kinase domain-like protein (MLKL) and pyroptosis executioner Gasdermin D (GSDMD) activation. Mechanistically, diminishing BDNF synthesis in myotubes enhances the accumulation of mitochondrial reactive oxygen species (mtROS), which sensitizes the cells towards TNFα-induced receptor-interacting protein kinase (RIPs) activation and promotes the formation of NLR family pyrin domain containing 3 (NLRP3)-containing inflammasome. BDNF deficiency-induced cell death could be alleviated by scavenging mtROS, suppressing the activity of GSDMD, or inhibiting receptor-interacting kinase 3 (RIP3). Similarly, supplementation of BDNF mimetics, suppression of RIP3 activity, increasing the intramyocellular antioxidant, or enhancing mitophagy ameliorated the myopathies of MBKO mice and improved their muscle strength. Together, our study demonstrates that insufficient BDNF production in mouse muscle causes the development of pathological features of myositis via enhancing oxidative stress, necroptosis, and pyroptosis in myofibers.

Caspase-8-and Gasdermin D (GSDMD)-Dependent PANoptosis Participate in the Seasonal Atrophy of Scented Glands in Male Muskrats.

The muskrat (Ondatra zibethicus) is an animal with special economic significance whose scented glands rapidly atrophy during the non-breeding season, but the mechanism of atrophy is not clear, with significant differences in apoptotic and pyroptotic signaling pathway expression according to transcriptome sequencing. During the non-breeding season, key apoptosis-related genes such as Tnfr1 (TNF Receptor Superfamily Member 1A), TRADD (TNFRSF1A Associated via Death Domain), FADD (Fas Associated via Death Domain), Casp-8 (Cysteine-aspartic proteases-8), and Bax (Bcl-associated X protein) were upregulated in the scented glands, while Bcl2 (B-cell lymphoma-2) expression was downregulated. In the classical pyroptosis pathway, the mRNA expression levels of key genes including Nlrp3 (the Nod-like receptor family pyrin domain-containing 3), ASC (the apoptosis-associated speck-like protein), Casp-1 (Cysteine-aspartic proteases-1), Gsdmd (Gasdermin D), and IL-1β (Interleukin 1 Beta) were higher during the non-breeding season, similar to the transcription level of Ripk1 (Receptor Interacting Serine/Threonine Kinase 1) in the non-canonical pyroptosis pathway, while TAK1 (transforming growth factor kinase) expression was downregulated in this latter pathway. TUNEL assays and immunofluorescence analysis indicated increased apoptosis and GSDMD and Caspase-8 protein levels during the non-breeding season. Indeed, the protein levels of GSDMD-N, Caspase-8 p43, and Caspase-8 p18 were significantly higher during the non-breeding season, while the GSDMD levels were significantly lower compared to the secretion season. These results suggest that apoptosis and pyroptosis play regulatory roles in scented gland atrophy and that there is an interplay between them during this process.

Quercetin Boosts Pulsatile Gonadotropin-Releasing Hormone Release to Improve Luteal Function via Inhibiting NF-κB/NLRP3-Mediated Neuron Pyroptosis.

Luteal phase deficiency (LPD) is the main cause of infertility without an effective cure. Quercetin (QUE) is a bioactive flavonoid with antioxidant properties, while its role in treating LPD remains unclear. This study aims to investigate the therapeutic effects of QUE on infertility and menstrual disorders induced by LPD, thus further exploring the underlying mechanism. Mifepristone-induced rats are used to explore the protective effects of QUE against LPD. QUE stimulates the spontaneous secretion of progesterone to improve luteal function and endometrial receptivity in LPD rats by activating the kisspeptin/GPR54 system to facilitate the gonadotropin-releasing hormone (GnRH) pulsatility. Bioinformatics analysis reveals that the core mechanism of QUE in treating LPD is to attenuate the GnRH neuron pyroptosis by inhibiting the NF-κB pathway, which is further verified in LPD rats and lipopolysaccharide (LPS)-treated GT1-7, as QUE significantly reduces the expression of key factors concerning NF-κB pathway and NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome. This study first proposes that neuron pyroptosis-induced GnRH pulsatility disruption accounts for the pathogenesis of LPD, and QUE facilitates the pulse secretion of GnRH to boost the spontaneous progesterone secretion by inhibiting NF-κB/NLRP3-mediated neuron pyroptosis, which provides a new therapeutic target and strategy for LPD.

Expression of NLRP3 in serum and induced sputum of children with asthma and their relationship with disease severity

ObjectivesThe aim of this cross-sectional study is to investigate the levels of NLRP3 in the serum and induced sputum of children with asthma and their potential association with lung function and disease severity.MethodsThis cross-sectional study included 83 children with bronchial asthma who sought medical care at our hospital from May 2023 to February 2024. Portable spirometry was used to monitor lung function parameters, including forced vital capacity, forced expiratory volume in 1 s, peak expiratory flow. The expression of C-reactive protein (CRP), interleukin (IL)-6, IL-1β, TNF-α, and Nod-like receptor family pyrin domain-containing 3 (NLRP3) in the serum and induced sputum were measured by enzyme-linked immunosorbent assay. Data analysis was performed using SPSS 25.0 and differences with P < 0.05 were considered statistically significant.ResultsChildren with asthma exhibited significantly elevated levels of serum NLRP3, CRP, IL-6, IL-1β, and TNF-α compared to healthy controls. In addition, children with moderate–severe asthma had significantly higher levels of serum and induced sputum NLRP3 and IL-1β compared to children with mild asthma. Spearman’s correlation analysis revealed a positive correlation between induced sputum NLRP3 and IL-6. Moreover, induced sputum NLRP3 was negatively correlated with lung function parameters. The results of receiver operating characteristic curves showed that induced sputum NLRP3 could be used for diagnosing children with moderate–severe asthma, with an AUC was 0.758, cutoff value of 3.33 ng/mL, sensitivity of 66.1%, and specificity of 70.8%. Furthermore, the logistic regression analysis revealed that serum and induced sputum NLRP3, induced sputum IL-6 and IL-1β were risk factors for children with moderate–severe asthma.ConclusionsIn this cross-sectional study, we found a significant increase in NLRP3 levels in induced sputum of children with asthma, which further increased in those with moderate–severe disease. The levels of NLRP3 in induced sputum could serve as potential biomarkers for assessing disease severity.

Radish red protects against early diabetic kidney disease through inhibiting inflammation, pyroptosis and insulin resistance via IRAK1 signaling suppression

Diabetic kidney disease (DKD) is a major diabetic complication and a leading cause of end-stage renal disease (ESRD), but the therapeutic strategies for DKD are still limited. Red radishes (Raphanus sativus L.) are a rich source of natural anthocyanins that have antioxidant, anti-apoptotic and anti-inflammatory activities. In this study, we attempted to explore the effects of natural pigment anthocyanin called radish red (RR) extracted from red radishes on DKD progression and the underlying molecular mechanisms. RR dose-dependently reduced the tubular cell injury, indicated by the decreased expression of kidney injury molecule 1 (KIM1). Furthermore, releases of pro-inflammatory cytokines including interleukin-1β (IL-1β), IL-6 and tumor necrosis factor-α (TNF-α) stimulated by HF were strongly relieved by RR. Inflammatory response and pyroptosis were also identified to be induced by HF stimulation but were mitigated by RR in HK2 cells through repressing nuclear factor-κB (NF-κB) activation and NLR family, pyrin domain-containing 3 (NLRP3) inflammasome. IR and lipogenesis due to HF exposure were also significantly ameliorated by RR in HK2 cells. Mechanistically, RNA-Seq analysis showed that RR strongly depressed interleukin-1 receptor-associated kinase-1 (IRAK1)-mediated NLRP3 inflammasome, pyroptosis, IR and lipid deposition. Importantly, IRAK1 overexpression almost diminished the beneficial effects of RR, while being rescued upon NLRP3 knockdown in HF-treated HK2 cells, revealing that RR performed its nephroprotective functions in diabetic kidney via inactivating the IRAK1-NLRP3 signaling pathway. Similarly, animal studies confirmed that RR supplementation efficiently ameliorated HFF-caused metabolic disturbance, IR, renal dysfunctions in mice and improved structural kidney damage. Consistently, RR consumption dramatically reduced lipid accumulation, inflammatory response and pyroptosis in kidney tissues of HFF-challenged mice mainly through repressing IRAK1-NLRP3 axis. Our results demonstrated that dietary supplementation with RR may serve as an IRAK1-NLRP3 inhibitor for preventing and treating diabetic nephropathy.

Korean Red Ginseng relieves the inflammation and oxidative stress induced by pseudo-typed SARS-CoV-2

BackgroundDeveloping antiviral agents against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been a global goal since the Coronavirus Disease 2019 (COVID-19) pandemic emerged in 2019. Korean Red Ginseng (KRG), recognized for its immunomodulating and antiviral properties, may be effective against SARS-CoV-2. Therefore, we aimed to investigate the efficiency of KRG in a human angiotensin-converting enzyme 2 (hACE2)-expressing mouse model infected with pseudo-typed SARS-CoV-2 (PSV). MethodsThe lung injury score was assessed using H&E staining, and the immune cell population shift in the lung and spleen was observed through flow cytometry. Serum IgM and IgG concentrations were quantified using enzyme-linked immunoassay (ELISA). Pro-inflammatory cytokine levels were measured by cytometric bead assay (CBA) and polymerase chain reaction (PCR). Additionally, the expression of NLR family pyrin domain containing 3 (NLRP3) and inflammation-related transcription factors was detected by immunoblotting. RNA-sequencing and antibody array assays reconfirmed gene expression in inflammation and oxidation. ResultsKRG extract was most effective in treating lung injuries and serum IgM and IgG levels. Also, immune cells, including neutrophils, were regulated in the lungs, and tumor necrosis factor-alpha (TNF-a) levels were reduced. NLRP3 and phosphorylated nuclear factor-κB (NF-kB) and activator protein 1 (AP-1) were downregulated. Heme oxygenase-1 (HO-1) expression was increased, indicating that KRG extract has antioxidant properties. RNA-sequencing and antibody array assays revealed that KRG extract regulates the expression of genes associated with inflammation and oxidative damage. ConclusionsThis study demonstrates that KRG extract may suppress PSV-induced inflammation and oxidative stress, making it a viable antiviral functional food.

Metasilicate-based alkaline mineral water improves the growth performance of weaned piglets by maintaining gut-liver axis homeostasis through microbiota-mediated secondary bile acid pathway

Weaning stress causes substantial economic loss in the swine industry. Moreover, weaning-induced intestinal barrier damage and dysfunction of the gut-liver axis are associated with reduced growth performance in piglets. Metasilicate-based alkaline mineral water (AMW) has shown potential therapeutic effects on gastrointestinal disorders; however, the mechanisms involved and their overall effects on the gut-liver axis have not been explored. Here, sodium metasilicate (SMS) was used to prepare metasilicate-based AMW (basal water + 500 mg/L SMS). A total of 240 newly weaned piglets were allocated to the Control and SMS groups (6 replicate pens per group and 20 piglets per pen) for a 15-day trial period. Histopathological evaluations were conducted using hematoxylin and eosin staining. To analyze the composition of the gut microbiota, 16S rRNA PacBio SMRT Gene Full-Length Sequencing was performed. Western blotting and immunofluorescence were employed to assess protein expression levels. Our results indicated that metasilicate-based AMW effectively alleviated weaning-induced colonic or liver morphological injury and inflammatory response, as well as liver cholesterol metabolism disorders. Further analysis showed that metasilicate-based AMW promoted deoxycholic acid (DCA) biosynthesis by increasing the abundance of Lactobacillus_delbrueckii in the colon (P < 0.001). This consequently improved weaning-induced colon and liver injury and dysfunction through the DCA-secondary bile acid (SBA) receptors (SBAR)-nuclear factor-kappaB (NF-κB)/NOD-like receptor family pyrin domain-containing 3 (NLRP3) pathways. Growth performance parameters, including final body weight (P = 0.034) and average daily gain (P < 0.001), in the SMS group were significantly higher than those in the Control group. Therefore, metasilicate-based AMW maintains gut-liver axis homeostasis by regulating the microbiota-mediated SBA-SBAR pathway in piglets under weaning stress. Our research provides a new strategy for mitigating stress-induced gut-liver axis dysfunction in weaned piglets.