Search Results (2,128)

Traditional treatments of autoimmune diseases relying on systemic immunosuppression often lack curative potential and have severe side effects. Mesenchymal stem cells (MSCs) are a promising alternative due to their immunomodulatory properties; however, whole-cell therapies have certain limitations. MSC-derived extracellular vesicles (EVs), including small vesicles—exosomes—have emerged as a safe cell-free therapeutic platform capable of crossing biological barriers and delivering bioactive cargo with low immunogenicity. Various types of RNAs abundantly produced by host MSCs represent a key element of EV content. In particular, EVs carry small RNAs, which essentially determine cellular life and fate. Our review provides a comprehensive mechanistic framework for the use of RNA-loaded EVs, specifically those carrying microRNAs (miRNAs), small interfering RNAs (siRNAs), and messenger RNAs (mRNAs), in restoring immune homeostasis. We detail the biogenesis and molecular mechanisms governing sorting of RNA into EVs, along with endogenous and exogenous engineering strategies to enhance therapeutic potency. We examine how RNA-loaded EVs modulate immunological processes like reprogramming of macrophage M1-M2 polarization, Th17/Treg balance, and suppression of inflammatory signaling pathways such as NF-κB and the NLRP3 inflammasome. We address critical translational challenges—EV heterogeneity, manufacturing scalability, and need for standardized quality control—while outlining future opportunities for RNA-loaded EV-based therapeutics. Full article

This study explored the regulatory role of nuclear factor E2-related factor 2 (Nrf2) in aerobic exercise improving oxidative stress and inflammatory responses in mice with insulin resistance (IR) induced by a high-fat diet. We established an IR mouse model through a high-fat diet, then subjected the IR mice to aerobic exercise, intraperitoneal injection of luteolin, or a combined intervention. After 6 weeks of intervention, we measured serum lipid and glucose profiles; evaluated skeletal muscle morphology by H&E staining; quantified mRNA expression levels of Nrf2 and its downstream targets in the skeletal muscle by RT-qPCR; and determined protein abundance, localization, and expression patterns of Nrf2 and NOD-like receptor protein 3 (NLRP3) inflammasome by Western blotting and immunohistochemistry, respectively. In the skeletal muscle of IR mice, Nrf2 and its downstream targets were significantly down-regulated, whereas NLRP3 inflammasome was markedly up-regulated (p < 0.05 or p < 0.01). IR mice subjected to aerobic exercise exhibited reduced serum glucose and lipid levels together with a lower insulin-resistance index (p < 0.05 or p < 0.01); morphologically, inter-myofibrillar spaces were narrowed, intrafiber vacuoles diminished, and cellular integrity restored. Concomitantly, Nrf2 and its downstream targets were up-regulated, whereas NLRP3 inflammasome components were down-regulated in the skeletal muscle (p < 0.05 or p < 0.01). Intraperitoneal administration of luteolin during exercise, however, partially attenuated or reversed these exercise-induced improvements by inhibiting the activation of Nrf2 (p < 0.05 or p < 0.01). These results indicate that aerobic exercise confers protective effects against IR by activating the Nrf2 signaling pathway, thereby attenuating oxidative stress and inflammation; these benefits are markedly attenuated when Nrf2 activity is pharmacologically inhibited. Full article

Background: The gut microbiota and its metabolite short-chain fatty acids (SCFAs) regulate host physiology, but whether butyrate, a key SCFA, protects against myocardial injury via the gut–heart axis remains unclear. Objectives: This study aimed to investigate the cardioprotective effect of butyrate in a rat model of isoproterenol (ISO)-induced myocardial injury and to explore its underlying gut–heart mechanism. Methods: In this experimental study, male Sprague-Dawley rats received intragastric butyrate pre-treatment followed by ISO injection to induce myocardial injury. Cardiac function, myocardial remodeling, gut–heart homeostasis, intestinal barrier integrity, and the expression of Tas2r, GPR41/43, and NLRP3 pyroptosis pathway components were assessed. Results: Butyrate pre-treatment significantly restored cardiac function (LVEF increased by 19.67 units; 95% CI, 11.17–28.16; p < 0.001) and ameliorated electrophysiological abnormalities (QTc shortened by 63.21 ms; 95% CI, 45.45–80.97; p < 0.0001). Mechanistically, butyrate suppressed aberrant myocardial Tas2r signaling (Tas2r137 reduced by 1.06 units; 95% CI, 0.37–1.74; p < 0.01), upregulated GPR41/43, inhibited NLRP3 inflammasome activation (NLRP3 reduced by 1.23 units; 95% CI, 0.13–2.33; p < 0.05), and repaired intestinal barrier integrity, thereby reducing bacterial translocation and secondary injury. Conclusions: Butyrate ameliorates ISO-induced myocardial injury through a simultaneous gut–heart mechanism, acting on both the cardiac Tas2r137/GPR41/43-NLRP3 pathway and intestinal barrier protection. These findings identify butyrate as a key functional molecule in gut–heart crosstalk and suggest its potential as a therapeutic agent for myocardial injury. Full article

Diabetic kidney disease (DKD) is a primary cause of end-stage renal disease (ESRD), and while ferroptosis is known to contribute to DKD pathogenesis, the regulatory role of the NLRP3 inflammasome in this process remains elusive. To address this research gap, we explored whether NLRP3 inhibition alleviates DKD by suppressing ferroptosis using streptozotocin-induced diabetic wild-type and NLRP3-knockout C57BL/6 mice, alongside high-glucose-cultured (30 mM) human renal tubular epithelial (HK-2) cells with or without siNLRP3 transfection. Inflammatory cytokines (IL-6, TNF-α, and IL-1β) were measured using an ELISA; oxidative stress markers (CSSG, MDA, GSH, and ROS) and the iron ion content via colorimetric assays; mitochondrial morphology by transmission electron microscopy (TEM); and ferroptosis-related proteins (ACSL4, COX2, and GPX4) through Western blotting. Our findings demonstrate that NLRP3-knockout diabetic mice displayed markedly reduced urinary albumin excretion and serum creatinine levels (p < 0.01) compared with wild-type diabetic controls, concurrent with suppressed renal iron overload and ferroptosis, diminished inflammatory cytokine levels, and attenuated oxidative stress. Pathological assessments further revealed ameliorated renal fibrosis and preserved mitochondrial ultrastructure in NLRP3-deficient mice. In vitro, siNLRP3 transfection abrogated high-glucose-induced inflammation, oxidative stress, and ferroptosis in HK-2 cells, effects that were reversed by the ferroptosis inducer erastin (p < 0.01). Mechanistically, NLRP3 deficiency was associated with upregulated GPX4 expression and downregulated ACSL4 and COX2 expression. Collectively, these results indicate that inhibition of the NLRP3 inflammasome mitigates DKD progression by suppressing ferroptosis, underscoring its translational potential as a therapeutic target for this condition. Full article

The innate immune system serves as the primary barrier against viral invasion, utilizing pattern recognition receptors (PRRs) to orchestrate a rapid defense. Among these, the nucleotide-binding domain and leucine-rich repeat (NLR) containing proteins function as central signaling scaffolds, assembling into multiprotein complexes known as inflammasomes. These complexes drive the maturation of pro-inflammatory cytokines IL-1β and IL-18, and initiate gasdermin D (GSDMD)-mediated pyroptosis, a lytic cell death pathway that eliminates intracellular replication niches. This comprehensive review synthesizes the diversified landscape of inflammasome activation during viral infections, extending beyond the canonical NLRP3 inflammasome to include specialized sensors such as NLRP6, NLRP9, NLRP1, NLRP12, and NLRC4. We critically evaluate the evolutionary “arms race” between host defenses and viral pathogens, detailing the sophisticated immune evasion strategies employed by viruses—ranging from the expression of decoy proteins and direct proteolytic cleavage of immune sensors to the manipulation of post-translational modifications (PTMs). Furthermore, we discuss the dual nature of inflammasome activation, which balances protective viral clearance against pathological hyperinflammation, and provide an exhaustive analysis of novel therapeutic strategies, including direct NLR inhibitors and downstream cytokine blockers, currently navigating clinical transition. Full article

Background/Objectives: Clinical application of Doxorubicin (Doxo) is limited by cardiotoxicity, a process strongly associated with an interplay between oxidative stress and inflammatory signaling, particularly Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation and Nucleotide oligomerization domain-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome engagement. Identifying strategies capable of mitigating these interconnected pathways is of critical importance in cardio-oncology. Simvastatin (SIM) is a promising option since it modulates oxidative stress, inflammation, and cell death through its pleiotropic effects, so this study aimed to evaluate whether SIM attenuates Doxo-induced inflammatory responses. Methods: Human Cardiomyocyte (HCM) cells were pre-treated with SIM (10 µM) for 4 h and then co-exposed to SIM and Doxo (1 µM) for 20 h. Cytofluorimetric analysis was used to evaluate inducible nitric oxide synthase (iNOS), Connexin 43 (Cx43), and Cx43 phosphorylated at Serine 368 (p^S368Cx43) levels. Real-time qPCR was performed to evaluate iNOS gene expression, while Nitric oxide (NO) release was evaluated by spectrophotometric analysis. Interleukin (IL)-1β, IL-18, IL-6, tumor necrosis factor alpha (TNF-α) production, and NLRP3 levels were evaluated by means of ELISA assay. Expression levels of inhibitor of nuclear factor kappa B alpha (IκB-α), Caspase-1, and Gasdermin D (GSDMD) were evaluated by Western Blot analysis. Nuclear translocation of NF-κB was evaluated by immunofluorescence assay. Results: In our experimental model, SIM significantly (p < 0.01) reduced Doxo-induced nitrite release, as well as iNOS gene expression (p < 0.05) and protein levels (p < 0.01). SIM also markedly attenuated Doxo-induced NF-κB signaling, pro-inflammatory cytokines production (TNF-α and IL-6, p < 0.01), and inflammosome-related responses (cleaved caspase-1, IL-1β, N-terminal domain of GSDMD), and NLRP3 expression p < 0.05). Additionally, SIM significantly attenuated the overexpression of Cx43 and its phosphorylated form (p^S368Cx43), which are responsible for impairing intercellular communication and electrical coupling in cardiomyocytes and contribute to arrhythmias and conduction abnormalities characteristic of acute Doxo-induced cardiotoxicity. Conclusions: Overall, these findings demonstrate that SIM exerts a multifaceted cardioprotective effect against Doxo-induced injury, thereby targeting interconnected inflammatory and pro-arrhythmic pathways implicated in Doxo cardiotoxicity. Full article

Background: Mushrooms have gained attention for their potential to improve brain health. We evaluated extracts of king oyster mushroom, as well as two of its bioactive compounds—ergothioneine (ERG) and N-acetyltryptamine (NAT)—for their ability to prevent microglia activation by reducing neuroinflammation and oxidative stress. Methods: HAPI microglial cells were pretreated with king oyster extracts (crude powder, acetone, ethanol, and methanol extracts at 100 μg/mL) and pure bioactive molecules of ergothioneine (ERG, 500 μM) and N-acetyl-tryptamine (NAT,50 μM) before stimulation with LPS. The effects on nitrite; TNF-α; and expressions of the inflammatory proteins iNOS, NOX2, and NLRP3 were compared with those of a blueberry extract (BB, 500 μg/mL) as a positive control. Results: All extracts and bioactive molecules significantly reduced nitrite production, similar to the BB. Overall, the best results for reducing inflammation and inflammatory protein expression were obtained with the extracts rich in NAT (acetone and ethanol), as well as pure NAT. Furthermore, through their inhibitory target effect on NLRP3, these two extracts and the bioactive compounds (NAT and ERG), like BB, are attractive therapeutic molecules to reduce mood disorders related to brain aging, due to evidence of enhanced Nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing-3 (NLRP3) inflammasome activity in common neurodegenerative diseases. Further interventional studies are needed to confirm mushrooms’ brain health properties. Full article

Background/Objectives: Chronic low-grade inflammation, underpinned by persistent activation of the NLRP3 inflammasome, is a central pathological mechanism in non-communicable diseases including cardiovascular disease, type 2 diabetes, inflammatory bowel disease, and neurodegeneration. Dietary polyphenols have been consistently associated with reduced inflammatory burden; however, the mechanisms underlying these effects remain incompletely understood. This review aims to characterize the gut microbiota–polyphenol–NLRP3 inflammasome axis as a central regulatory network through which diet modulates innate immune signaling and chronic inflammatory tone. Methods: A comprehensive narrative review of the available literature was conducted, integrating evidence from mechanistic studies in cell culture and animal models, microbiome research, metabolomics, and human epidemiological and interventional data. Results: The gut microbiota emerges as a critical biochemical intermediary that transforms dietary polyphenols into bioactive metabolites, including urolithins, phenyl-γ-valerolactones, protocatechuic acid, and short-chain fatty acids, with enhanced bioavailability and potent inflammasome-modulating properties. These compounds suppress NLRP3 activation through multiple converging mechanisms, including inhibition of NF-κB-dependent priming, mitochondrial quality control via mitophagy, Nrf2-mediated antioxidant responses, and HDAC inhibition. Evidence across cardiovascular, metabolic, neurological, and respiratory disease models supports the translational relevance of this axis. Conclusions: The microbiota–polyphenol–NLRP3 axis functions as an integrated, self-regulated network in which each component simultaneously shapes and is shaped by the others: dysbiosis primes NLRP3 and depletes protective metabolites, while inflammasome hyperactivation further destabilises microbial ecology; polyphenol biotransformation by specific taxa interrupts this feed-forward loop at multiple nodes, restoring homeostasis. Full article

Endometriosis is a chronic inflammatory disorder affecting approximately 10% of reproductive-age women, yet non-hormonal therapeutic options remain limited. This study investigates the role of the TLR4/NF-κB/NLRP3 inflammasome axis in endometriosis pathogenesis and evaluates the therapeutic potential of pharmacologic TLR4 inhibition. Ectopic endometriotic tissues, eutopic endometrium, and peritoneal fluid were collected from 15 patients with ovarian endometriosis and 15 control subjects. The endometriotic epithelial cell line 11Z was stimulated with LPS and ATP with or without the TLR4 inhibitor TAK-242. A murine endometriosis model was established in wild-type C57BL/6 and TLR4⁻/⁻ mice treated with TAK-242. Expression of TLR4, p-p65, NLRP3, caspase-1, cleaved caspase-1 (p20), GSDMD-N, IL-1β, PCNA, and CD31 was assessed by qPCR, Western blot, IHC, and ELISA. Ectopic lesions showed significantly elevated TLR4/NF-κB/NLRP3/IL-1β signaling compared with eutopic and control endometrium (all p < 0.05). Peritoneal fluid IL-1β was increased in patients, indicating a localized pelvic inflammatory response. In vitro, TAK-242 suppressed LPS/ATP-induced NF-κB/NLRP3 activation, pyroptosis, and IL-1β secretion (p < 0.05). Furthermore, the NLRP3-specific inhibitor MCC950 confirmed the essential role of NLRP3 inflammasome activation in IL-1β maturation. In vivo, TLR4 deletion or TAK-242 treatment reduced lesion weight, PCNA proliferation, and CD31 microvessel density (all p < 0.05). TLR4 inhibition blocks NF-κB nuclear translocation and subsequent inflammasome activation, suggesting a potential role in attenuating inflammation and angiogenesis. The TLR4/NF-κB/NLRP3 axis may drive endometriosis progression by linking innate immunity, inflammasome activation, pyroptosis, with possible involvement in angiogenesis warranting further investigation. Pharmacological inhibition of TLR4 attenuates lesion growth, supporting TLR4 as a promising non-hormonal therapeutic target for endometriosis. Full article

Substances released by cardiomyocytes after myocardial infarction (MI) lead to inflammasome assembly. Heart failure (HF) is associated with skeletal muscle inflammation. Methotrexate (MTX) reduces cardiovascular outcomes in chronic inflammation patients. Lipid core nanoparticle-associated MTX (MTX-LDE) attenuated cardiac remodeling in MI rats. We investigated the effects of early MTX-LDE administration on cardiac remodeling and inflammasomes in soleus muscle of MI rats. Wistar rats were separated into Sham, MI, and MI-MTX groups. MTX was initiated 24 h after MI at 1 mg/kg/week intraperitoneally for 10 weeks. Soleus protein expression of NLRP1, NLRP3, NLRC4, ASC, procaspase-1, Caspase-1, pro-IL-1β, and IL-1β was quantified by Western blotting; Nlrp1a, Nlrp3, Nlrc4, Pycard (Asc), Casp1, and Il1b gene expression was assessed by qPCR; and statistical analysis used Student’s t test and ANOVA. Rats with infarction size > 35% total left ventricle (LV) area were included in the study; infarction size did not differ between groups. Echocardiogram showed infarcted groups with LV dilation and dysfunction. Diastolic function was worse in MI-MTX than MI. NLRP1 and NLRC4 protein expression was lower in MI-MTX than Sham. Expression of other proteins and gene expression did not differ between groups. Early MTX-LDE administration reduces NLRP1 and NLRC4 protein expression in soleus muscle without improving cardiac remodeling in rats. Full article

Peri-implant inflammatory disease exhibits marked clinical heterogeneity that cannot be explained solely by microbial burden, indicating the involvement of host-driven amplification mechanisms. This review integrates evidence from redox biology, immunometabolism, and biomaterials science to describe a redox amplification interface (RAI) linking immune-derived reactive oxygen species (ROS), mitochondrial dysfunction, and biomaterial electrochemical reactivity at the host–implant interface. Persistent NADPH oxidase activation promotes mitochondrial oxidative damage, including electron transport chain disruption, cardiolipin oxidation, and ROS-induced ROS release, resulting in sustained intracellular oxidative flux. Mitochondrial dysfunction further contributes to inflammatory amplification through release of damage-associated molecular patterns and activation of inflammasome signaling. Concurrent impairment of antioxidant systems, particularly Nrf2-dependent pathways and glutathione depletion, reduces redox buffering capacity and facilitates propagation of oxidative stress. Inflammatory microenvironments also destabilize implant surface electrochemistry, promoting corrosion, ion release, and surface-mediated redox reactions that increase local oxidative burden. These interacting processes form a coupled system capable of sustaining inflammation independently of the initiating microbial stimulus. This framework provides a mechanistic basis for disease heterogeneity and identifies redox-targeted therapeutic and biomaterial design strategies. Full article

Artemisia indica Willd. is widely used in traditional medicine and dietary practices. Phytochemical analysis of Artemisia indica Willd. aqueous extract (AAE) by HPLC–ESI–MS/MS identified isochlorogenic acid C (ICAC) as a major constituent. Angiotensin II (Ang II) disrupts renal tubular epithelial cell homeostasis and contributes to renal injury. In this study, we evaluated the protective effects of AAE and ICAC in Ang II-stimulated NRK52E cells. Both AAE and ICAC significantly reduced reactive oxygen species (ROS) production, mitochondrial dysfunction, and proinflammatory cytokine release. Mechanistic analyses showed that AAE inhibited Ang II type 1 receptor (AT1R)-mediated NF-κB activation and suppressed NLRP3 inflammasome signaling, thereby alleviating inflammatory responses and pyroptosis. In addition, AAE and ICAC restored sodium homeostasis by reactivating neural precursor cell expressed developmentally downregulated gene 4-like (Nedd4-2), promoting epithelial sodium channel (ENaC) ubiquitination and reducing its apical membrane accumulation. Molecular docking suggested that ICAC interacts with the extracellular domain of α-ENaC, supporting its regulatory role. Overall, AAE and ICAC protect renal tubular epithelial cells against Ang II-induced injury by reducing oxidative stress, inflammation, and dysregulated sodium transport, highlighting their potential as plant-derived therapeutic agents for hypertension-associated renal dysfunction. Full article

Mycobacterium bovis, the causative agent of bovine tuberculosis, infects and persists within macrophages, triggering pro-inflammatory responses. While these mechanisms are well characterized for Mycobacterium tuberculosis, less is known about host responses to M. bovis. Inflammasome activation and IL-1β production have been linked to ESAT-6, a substrate of the ESX-1 secretion system present in both species. Here, we examined inflammasome activation in bovine macrophages infected with the virulent M. bovis strain Mb04-303. M. bovis AF2122/97 and NCTC10772 upregulated IL-1β transcription, whereas Mb04-303 and BCG did not. Unexpectedly, deletion of the genes encoding ESAT-6 and CFP-10 from Mb04-303 enhanced inflammasome activation, as evidenced by increased NLRP3 and IL-1β transcription. Complementation with either wild-type ESAT-6/CFP-10 or the T63A ESAT-6 variant restored downregulation of the response, indicating that this substitution does not alter inflammasome modulation. In contrast, deletion of ESAT-6/CFP-10 from an attenuated M. bovis vaccine candidate reduced IL-1β transcription. No differences were observed between M. tuberculosis H37Rv and its ESAT-6-deficient mutant in bovine macrophages. Together, these findings demonstrate that ESAT-6/CFP-10-mediated modulation of inflammasome activation in bovine macrophages is highly dependent on the mycobacterial genetic background. Full article

Intermittent fasting confers protection in diverse diseases through various mechanisms, including the clearance of senescent and pathogenic cells, modulation of tissue inflammation and enhancement of stem/progenitor cell niche and functionality. Our previous study demonstrated the beneficial impact of alternate-day fasting (ADF) on xerostomia and sialadenitis, along with an improvement in salivary gland ductal compartments, where salivary gland progenitor cells reside, in non-obese diabetic mice, a spontaneous model of Sjögren’s syndrome (SS). In the present study, we induced SS-associated hyposalivation in KRT5^CreERT2; R26^tdTomato lineage tracing mice by immunizing them with submandibular gland proteins from wild-type C57BL/6 mice. ADF alleviated salivary gland hypofunction, which was accompanied by decreased expression of the senescent cell marker p16^INK4a, reduced protein levels of anti-apoptotic proteins BCL-2, BCL-XL, and MCL-1, and attenuated NLRP3 inflammasome activity in the submandibular glands, particularly within the ductal compartments, of this inducible model. Furthermore, immunofluorescence staining of submandibular gland sections revealed the expression of the acinar cell marker aquaporin 5 in a small subset of Keratin 5⁺ cells in 2 of 9 mice that were subjected to ADF, whereas no such cells were detected in the control mice. Taken together, these findings indicate that ADF favorably modulates the salivary gland progenitor cell niche, potentially by promoting apoptosis-mediated senescent cell clearance, suppressing NLRP3 inflammasome signaling, and promoting Keratin 5⁺ progenitor cell-derived acinar cell replenishment, thereby contributing to the structural and functional restoration of damaged salivary glands in autoimmune exocrinopathy. Full article

Macrophages harness pattern recognition receptors (PRRs) to detect conserved bacterial components and mount effective immune responses. Many Gram-negative bacteria modify their lipid A structures to limit recognition by Toll-like receptor 4 (TLR4) and cytosolic Caspase-11 lipopolysaccharide sensors. One common evasion strategy is to reduce the lipid A acylation state from hexa- to tetra-acylation. This alteration can limit binding to receptors and dampen subsequent immune signaling responses, yet the proteomic alterations associated with this altered immunogenicity remain incompletely understood. Here, we systematically profiled proteomic alterations induced by extracellular or transfected hexa-acylated Kdo2-lipid A (Kdo2) and tetra-acylated lipid-IVa (IVa) to assess TLR4-dependent, TLR4-independent, and non-canonical inflammasome activation pathways. Kdo2 elicited stronger inflammatory responses in immortalized bone-marrow-derived macrophages (iBMDMs), as evidenced by robust TNF production, Caspase-11 cleavage, and IL-1α/IL-1β release. In contrast, IVa elicited minimal TNF secretion and failed to effectively induce non-canonical inflammasome activation. Global label-free quantitative proteomic analysis of iBMDMs stimulated with a low dose of immunogenic LPS displayed route-specific immune signatures: enrichment of TNF signaling, interferon-associated pathways, and mitochondrial metabolic remodeling. Equimolar amounts of low-acylated LPS failed to effectively induce these immune signatures, supporting a threshold-dependent model in which the lipid A structure and route of exposure define inflammatory progression. Collectively, our findings provide mechanistic insight into how lipid A structural variation modulates macrophage immune programming and cytosolic inflammasome activation. Full article