NF-κB Nuclear Translocation Research Articles

A Novel Quinoline Inhibitor of the Canonical NF-κB Transcription Factor Pathway

The NF-κB family of transcription factors is a master regulator of cellular responses during inflammation, and its dysregulation has been linked to chronic inflammatory diseases, such as inflammatory bowel disease. It is therefore of vital importance to design and test new effective NF-κB inhibitors that have the potential to be utilized in clinical practice. In this study, we used a commercial transgenic HeLa cell line as an NF-κB activation reporter to test a novel quinoline molecule, Q3, as a potential inhibitor of the canonical NF-κB pathway. Q3 inhibited NF-κB-induced luciferase in concentrations as low as 5 μM and did not interfere with cell survival or induced cell death. A real-time PCR analysis revealed that Q3 could inhibit the TNF-induced transcription of the luciferase gene, as well as the TNF gene, a known downstream target gene. Immunocytochemistry studies revealed that Q3 moderately interferes with TNF-induced NF-κB nuclear translocation. Moreover, docking and molecular dynamics analyses confirmed that Q3 could potentially modulate transcriptional activity by inhibiting the interaction of NF-κB and DNA. Therefore, Q3 could be potentially developed for further in vivo studies as an NF-κB inhibitor.

Homocysteine aggravates intestinal inflammation through promotion of 5-LOX and COX-2 in IBD

BackgroundHomocysteine (Hcy) is a pro-inflammatory molecule that has the potential to induce oxidative damage to cells and stimulate the release of inflammatory mediators. Hcy has been observed to enhance the production of inflammatory agents in vascular endothelial cells. However, the impact of Hcy on intestinal mucosal inflammation remains largely unexplored. Therefore, the objective of this study was to examine the potential of Hcy to stimulate the synthesis of inflammatory mediators and elucidate the underlying mechanisms in the intestinal mucosa.MethodsA total of 99 patients diagnosed with inflammatory bowel disease (IBD) and 10 healthy individuals were included in this study to assess the impact of homocysteine (Hcy) on the levels of leukotriene E4 (LTE4) and prostaglandin E2 (PGE2). The underlying mechanism responsible for the generation of LTE4 and PGE2 induced by Hcy was investigated using colitis rats and Caco-2 cells. 32 Sprague–Dawley rats were categorized into four groups: normal control, TNBS model, normal with Hcy injection, and TNBS model with Hcy injection. The mRNA expressions of 5-LOX, COX-2, and NF-κB were assessed using reverse transcription quantitative polymerase chain reaction (RT-qPCR). Caco-2 cells were subjected to treatment with varying concentrations (10, 20, 50, 100 μmol/L) of Hcy and incubated for different durations (1, 3, 6 h). The alterations in NF-κB activity, as well as the levels of Hcy, LTE4, and PGE2, were measured using enzyme-linked immunosorbent assay (ELISA).ResultsThe excretion of Hcy, LTE4, and PGE2 in urine exhibited significant increases in patients with inflammatory bowel disease (IBD), Crohn's disease (CD), and ulcerative colitis (UC). In addition, Hcy demonstrated a significant increase in the expression of 5-LOX, COX-2, and NF-κB, as well as elevated levels of LTE4 and PGE2 in rats with colitis. Furthermore, Hcy was found to induce NF-κB activation and nuclear translocation, thereby contributing to the enhanced synthesis of LTE4 and PGE2 in Caco-2 cells.ConclusionsHcy was found to enhance the expression of 5-LOX and COX-2 by activating NF-κB, thereby augmenting the production of LTE4 and PGE2, which ultimately exacerbates colonic inflammation in individuals with inflammatory bowel disease (IBD).

Prolactin protects hippocampal neurons against H2O2-induced neurotoxicity by suppressing BAX and NOX4 via the NF-κB signaling pathway.

Reactive oxygen species (ROS) are physiological byproducts of neuronal metabolism. However, an imbalance between ROS generation and antioxidant capacity, often driven by dysregulated pro-oxidant enzymes like nicotinamide adenine dinucleotide phosphate oxidases (NOX), can result in deleterious oxidative stress. This oxidative stress is a critical factor in the pathogenesis of neurodegenerative diseases. While interventions with broad-spectrum antioxidants have demonstrated limited efficacy, the modulation of endogenous antioxidant mechanisms presents a promising therapeutic avenue. Here, we investigated the potential of the neuroprotective hormone prolactin to mitigate oxidative stress and subsequent neuronal cell death. Prolactin protected primary mouse hippocampal neurons from hydrogen peroxide (H2O2)-induced oxidative damage. Prolactin reduced ROS levels, lipid peroxidation, and apoptosis, and its effects were occluded by a specific prolactin receptor antagonist (G129R-hPRL). Mechanistically, prolactin suppressed H2O2-induced mRNA upregulation of pro-oxidative Nox4 and pro-apoptotic Bax. Moreover, prolactin induced nuclear factor kappa B (NF-κB) nuclear translocation, and the inhibition of the NF-κB signaling pathway abolished the neuroprotective and transcriptional effects of prolactin, indicating its central role in prolactin-mediated protection. Our findings indicate that prolactin exerts potent antioxidant and neuroprotective effects by modulating the expression of Nox4 and Bax, thereby reducing ROS generation and neuronal apoptosis. This study underscores the therapeutic potential of prolactin in attenuating oxidative stress and suggests a possible role in the treatment of neurodegenerative diseases.

Benzylurea Protects hPDLFs Against LPS-Induced Mitochondrial Dysfunction Through MTCH2.

The aim of this study is to explore the mechanism of benzylurea in the inflammatory injury of human periodontal ligament fibroblasts (hPDLFs). An inflammation model of hPDLFs was established using LPS. Nuclear transport of nuclear transcription factor-κB (NF-κB), secretion of cytokines, and the morphology and distribution of F-actin were determined. Mitochondrial function was assessed by measuring mitochondrial membrane potential (MMP), mitochondrial permeability transition pore (mPTP), and reactive oxygen species (ROS) levels. The expression of mitochondrial carrier homolog 2 (MTCH2) and Cytochrome b5 type B (CYB5B) was detected. Benzylurea alleviated the effects of lipopolysaccharide (LPS) on the proliferation and apoptosis of hPDLFs. It reduced the release of inflammatory cytokines and inhibited NF-κB nuclear translocation. Benzylurea improved mitochondrial function by regulating MMP and preventing excessive mPTP opening. Furthermore, LPS elevated the expression of MTCH2 and reduced the expression of CYB5B in hPDLFs. However, these effects can be inhibited by benzylurea. The altered expression of MTCH2 directly affected CYB5B expression, the release of inflammatory cytokines, and the activation of nuclear translocation of NF-κB. CYB5B may act as an effector of MTCH2, with benzylurea enhancing mitochondrial function and protecting hPDLFs from LPS-induced injury through MTCH2.

Human epicardial adipose tissue-derived factors promote atrial endothelial dysfunction: role of pro-inflammatory cytokines and AT1R/NADPH oxidases/SGLT2 pro-oxidant pathway

Abstract Introduction Epicardial adipose tissue (EAT) has been suggested to contribute to left atrium dysfunction via paracrine mechanisms to induce endothelial dysfunction, pro-arrhythmogenic and pro-remodeling responses thereby favoring atrial fibrillation (AF) onset. Recently, sodium-glucose co-transporter2 inhibitors (SGLT2i) have been shown to reduce AF incidence, EAT volume, differentiation and inflammation, however, the underlying mechanisms are unknown. Purpose This study investigates the impact of human EAT-derived mediators on atrial endothelial cell function and, if so, to characterize the role of SGLT2 using the inhibitor empagliflozin (EMPA). Methods Epicardial and subcutaneous adipose tissues (SAT) were collected from 70 cardiac patients at a university hospital. Conditioned medium (CM, 24 h) from fats were applied to porcine atrial endothelial cells (AECs, first passage) for 24 h. Histology of tissues was assessed by haematoxylin and eosin staining, protein expression by Western blot analysis or immunofluorescence staining, mRNA levels by RT-qPCR, formation of reactive oxygen species (ROS) and nitric oxide (NO) by fluorescent probes, and pro-inflammatory cytokine levels by ELISA. Results Compared to SAT, EATs were more vascularized with increased infiltration of M1-like macrophages, expression of proinflammatory cytokines (IL-1ß, IL-6, TNF-α), markers of ECs VCAM-1 and eNOS, fibrosis TGF-β, NADPH oxidases NOX-1 and SGLT1/2. These effects were associated with a pro-oxidant response that was inhibited by neutralizing Abs directed against IL-1ß or IL-6, and by inhibition of either NOS, NADPH oxidases, ACE, AT1R or SGLT2. Levels of SGLT2 and ROS in EATs were higher in AF compared to non-AF patients and progressively increasing with age. CM of EATs showed higher concentrations of IL-1ß, IL-6, TNF-α and MCP-1 than that of SAT. Exposure of AECs to CM of EATs increased the level of oxidative stress that was positively correlated to the level of pro-inflammatory cytokines, and reduced basal and bradykinin-induced NO formation that was prevented by EMPA. It also resulted in upregulation of p53 and SGLT2 expression, and nuclear translocation of NF-kB by CM of the top quartile inflamed EATs but not by the lowest quartile of EATs or SATs, prevented by EMPA. Conclusion The findings indicate that compared to SATs, the EATs showed higher in situ expression and release of pro-inflammatory cytokines that contributed to oxidative stress involving the AT1R/NADPH oxidases/SGLT2 pro-oxidant pathway. CMs of inflamed EATs induced AECs dysfunction, oxidative stress and activation of NF-kB involving pro-inflammatory cytokines and SGLT2. Thus, SGLT2i appear as an interesting strategy to decrease EAT inflammation and improve endothelial function contributing to prevent cardiac remodeling and fibrotic responses.

Anti-Inflammatory and Autophagy Activation Effects of 7-Methylsulfonylheptyl Isothiocyanate Could Suppress Skin Aging: In Vitro Evidence

Skin inflammation, characterized by redness, swelling, and discomfort, is exacerbated by oxidative stress, where compounds like 7-methylsulfonylheptyl isothiocyanate (7-MSI) from cruciferous plants exhibit promising antioxidant and anti-inflammatory properties, though their effects on skin aging and underlying mechanisms involving the NLRP3 inflammasome and autophagy are not fully elucidated. NLRP3 is a crucial inflammasome involved in regulating inflammatory responses, and our study addresses its activation and associated physiological effects. Using biochemical assays such as ELISA, RT-qPCR, Western blotting, confocal microscopy, and RNA interference, we evaluated 7-MSI’s impact on cytokine production, protein expression, and genetic regulation in Raw 264.7 and RAW-ASC cells. 7-MSI significantly reduced TNF-α, IL-1β, IL-6, COX-2, and PGE transcription levels in LPS-stimulated Raw 264.7 cells, indicating potent anti-inflammatory effects. It also inhibited NF-κB signaling and NLRP3 inflammasome activity, demonstrating its role in preventing the nuclear translocation of NF-κB and reducing caspase-1 and IL-1β production. In terms of autophagy, 7-MSI enhanced the expression of Beclin-1, LC3, and Atg12 while reducing phospho-mTOR levels, suggesting an activation of autophagy. Moreover, it effectively decreased ROS production induced by LPS. The interaction between autophagy and inflammasome regulation was further confirmed through experiments showing that interference with autophagy-related genes altered the effects of 7-MSI on cytokine production. Collectively, this study demonstrates that 7-MSI promotes autophagy, including ROS removal, and to suppress inflammation, we suggest the potential use of 7-MSI as a skin care and disease treatment agent.

Deleting fibroblast growth factor 2 in macrophages aggravates septic acute lung injury by increasing M1 polarization and inflammatory cytokine secretion.

Septic lung injury is strongly associated with polarization of M1 macrophages and excessive cytokine release. Fibroblast growth factor (FGF) signaling plays a role in both processes. However, the impact of FGF2 deficiency on macrophage polarization and septic acute lung injury remains unclear. To investigate this, we obtained macrophages from FGF2 knockout mice and examined their polarization and inflammatory cytokine expression. We also eliminated endogenous macrophages using clodronate liposomes and administered FGF2 knockout or WT macrophages intravenously in conjunction with cecal ligation and puncture (CLP) surgery to induce sepsis. In vitro analysis by flow cytometry and real-time PCR analysis demonstrated that FGF2 deficiency resulted in increased expression of M1 markers (iNOS and CD86) and inflammatory cytokines (CXCL1, IL1β, and IL6), especially after LPS stimulation. Additionally, immunofluorescence demonstrated increased nuclear translocation of p65 NF-κB in FGF2 knockout macrophages and RNA-seq analysis showed enrichment of differentially expressed genes in the IL17 and TNFα inflammatory signaling pathways. Furthermore, in vivo experiments revealed that depletion of FGF2 in macrophages worsened sepsis-induced lung inflammation, lung vascular leak, and lung histological injury, accompanied by an increase in CD86-positive cells and apoptosis. Our study suggests that FGF2 deficiency in macrophages plays a critical role in the pathogenesis of septic ALI, possibly because of the enhanced M1 macrophage polarization and production of proinflammatory cytokines. These findings provide empirical evidence for potential therapeutic interventions targeting FGF2 signaling to modulate the polarization of M1 and M2 macrophages in the management of sepsis-induced acute lung injury.

Scutellarein ameliorates dextran sulfate sodium-induced ulcerative colitis by inhibiting colonic epithelial cell proinflammation and barrier disruption.

Scutellarein (Scu) is a natural occurring flavonoid found in multiple traditional Chinese medicines such as Oroxylum indicum (L.) Kurz and Scutellaria baicalensis, with various pharmacological activities including anti-inflammation, anti-oxidation and myocardial protection. Here, we investigated the therapeutic efficacy of Scu on ulcerative colitis (UC) and the underlying mechanism. Efficacy of Scu on UC was evaluated in dextran sulfate sodium (DSS) induced colitis mouse model. Inflammation in colonic tissues was assessed by myeloperoxidase activity assay and RT-qPCR. Barrier proteins expression was examined using immunostaining and Western blot. IL-1β-treated HT-29 cells was used for mechanical investigation. Gavage of Scu significantly decreased the DAI score, improved colon shortening, ameliorated the pathological score in DSS-treated mice with better efficacy than the positive drug, 5-aminosalicylic acid. Scu also inhibited the expression levels of cytokines (Il-1β, Tnf-α, Il-1α, Il-6, and Cxcl1) as well as barrier proteins (E-cadherin, Occludin, and ZO-1) in colon tissues of DSS mice. In intestinal epithelial HT-29 cells, Scu attenuated the IL-1β-downregulated expression levels of E-cadherin, occludin, and ZO-1, while reduced IL-1β-upregulated IL-6 and IL-8 mRNA levels. Moreover, Scu inhibited the phosphorylation and nuclear translocation of NF-κB and suppression of NF-κB phosphorylation abolished IL-1β-disrupted epithelial barrier integrity and IL-1β-upregulated proinflammatory mediators expression in HT-29 cells. These data demonstrate that Scu is an efficacious therapeutic agent to treat UC. Inhibition of inflammatory responses and maintenance of epithelial barrier integrity through NF-κB signaling pathway underlines Scu therapeutic effect on UC.

Cimifugin Alleviates Chronic Constriction Injury of the Sciatic Nerve by Suppressing Inflammatory Response and Schwann Cell Apoptosis.

Inflammation and Schwann cell apoptosis play critical roles in neuropathic pain after sciatic nerve injury. This study aimed to explore the function and mechanism of cimifugin in lipopolysaccharide (LPS)-stimulated rat Schwann cells and sciatic nerves of rats treated with chronic constriction injury (CCI). Thermal, mechanical and cold hyperalgesia of rats in response to cimifugin or mecobalamin (the positive drug control) treatment were evaluated through behavioral tests. H&E staining of sciatic nerves was performed for pathological observation. ELISA was conducted to assess concentrations of inflammatory cytokines in rat serum and sciatic nerves. The intensity of S100β in sciatic nerves was determined using immunohistochemistry. Flow cytometry analysis was conducted for detection of Schwann cell apoptosis. RT-qPCR was performed to measure mRNA levels of inflammatory factors in Schwann cells. Immunofluorescence staining was performed to detect cellular p65/NF-κB activity. Western blotting was performed to quantify protein levels of apoptotic markers and factors associated with the NF-κB and MAPK pathways in rat nerves and Schwann cells. As shown by experimental data, cimifugin mitigated thermal, mechanical and cold hyperalgesia of CCI rats. Cimifugin repressed inflammatory cell infiltration, reduced proinflammatory cytokine levels while increasing anti-inflammatory factor (IL-10) level in serum or sciatic nerves of CCI rats. Cimifugin enhanced S100β expression and downregulated apoptotic markers in vivo. The anti-inflammatory and anti-apoptotic properties of cimifugin were verified in the LPS-stimulated Schwann cells. Moreover, cimifugin suppressed nuclear translocation of p65 NF-κB in vitro and repressed the phosphorylation of IκB, p65 NF-κB, p38 MAPK, ERK1/2, as well as JNK in CCI rats. In conclusion, cimifugin alleviates neuropathic pain after sciatica by suppressing inflammatory response and Schwann cell apoptosis via inactivation of NF-κB and MAPK pathways.

Change in Nfkb/Nrf2/Bax Levels by High Monomeric Polyphenols Berries Extract (HMPBE) in Acute and Chronic Secondary Brain Damage.

High Monomeric Polyphenols Berries Extract (HMPBE) is a formula highly rich in polyphenols clinically proven to enhance learning and memory. It is currently used to enhances cognitive performance including accuracy, working memory and concentration. Here, we investigated for the first time the beneficial effects of HMPBE in a mouse model of acute and chronic traumatic brain injury (TBI). HMPBE, at the dose of 15 mg/kg was able to reduce histological alteration as well as inflammation and lipid peroxidation. HMPBE ameliorate TBI by improving Nrf-2 pathway, reducing Nf-kb nuclear translocation and apoptosis, and ameliorating behavioral alteration such as anxiety and depression. Moreover, in the chronic model of TBI, HMPBE administration restored the decline of Tyrosine Hydroxylase (TH) and dopamine transporter (DAT) and the accumulation of a-synuclein into the midbrain region. This finding correlates the beneficial effect of HMPBE administration with the onset of parkinsonism related to traumatic brain damage. The data may open a window for developing new support strategies to limit the neuroinflammation event of acute and chronic TBI.

Exploration of Pharmacological Mechanism of Cinnamomum tamala Essential Oil in Treating Inflammation based on Network Pharmacology, Molecular Modelling, and Experimental Validation.

Cinnamomum tamala (Buch.-Ham.) T.Nees & Eberm., also known as Indian Bay leaf, holds a distinctive position in complementary and alternative medicinal systems due to its anti-inflammatory properties. However, the active constituents and key molecular targets by which C. tamala essential oil (CTEO) exerts its anti-inflammatory action remain unclear. The present study used network pharmacology and experimental validation to investigate the mechanism of CTEO in the treatment of inflammation. GC-MS analysis was used to identify the constituents of CTEO. The key constituents and core targets of CTEO against inflammation were obtained by network pharmacology. The binding mechanism between the active compounds and inflammatory genes was ascertained by molecular docking and molecular dynamics simulation analysis. The pharmacological mechanism predicted by network pharmacology was verified in lipopolysaccharide-stimulated murine macrophage (RAW 264.7) cell lines. Forty-nine constituents were identified by GC-MS analysis, with 44 constituents being drug-like candidates. A total of 549 compounds and 213 inflammation-related genes were obtained, revealing 68 overlapping genes between them. Compound target network analysis revealed cinnamaldehyde as the core bioactive compound with the highest degree score. PPI network analysis demonstrated Il-1β, TNF-α, IL8, IL6 and TLR4 as key hub anti-inflammatory targets. KEGG enrichment analysis revealed a Toll-like receptor signalling pathway as the principally regulated pathway associated with inflammation. A molecular docking study showed that cinnamaldehyde strongly interacted with the Il-1β, TNF-α and TLR-4 proteins. Molecular dynamics simulations and MMPBSA analysis revealed that these complexes are stable without much deviation and have better free energy values. In cellular experiments, CTEO showed no cytotoxic effects on RAW 264.7 murine macrophages. The cells treated with LPS exhibited significant reductions in NO, PGE2, IL-6, TNF-α, and IL-1β levels following treatment with CTEO. Additionally, CTEO treatment reduced the ROS levels and increased the antioxidant enzymes such as SOD, GSH, GPx and CAT. Immunofluorescence analysis revealed that CTEO inhibited LPS-stimulated NF-κB nuclear translocation. The mRNA expression of TLR4, MyD88 and TRAF6 in the CTEO group decreased significantly compared to the LPS-treated group. The current findings suggest that CTEO attenuates inflammation by regulating TLR4/MyD88/NF- κB signalling pathway.

Lutein, a versatile carotenoid: Insight on neuroprotective potential and recent advances

BackgroundNeurodegenerative diseases (NDDs) are a diverse group of neurological disorders with progressive neuronal loss at specific brain regions, leading to impaired cognitive functioning, loss of neuroplasticity, severe neurological impairment, and dementia. The incidence of neurodegenerative diseases is increasing at an alarming rate with current treatments struggling to barely prolong the inevitable. The desperation to discover a therapeutic agent to treat neurodegenerative diseases and to aid in the process of healthy recovery has opened a gateway into natural pigments. HypothesisThe xanthophyll pigment lutein may bear the potential as a therapeutic agent against NDDs. ResultsLutein plays an important role in brain development, cognitive functioning, and improving neuroplasticity. In vitro and in vivo studies revealed the neuroprotective properties of lutein against NDDs such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and cerebral ischemia. The neuroprotective effect of lutein is evidenced by the reduction of free radicals and the simultaneous strengthening of the endogenous antioxidant systems by activating the NRF-2/ERK/AKT pathway. Further, it effectively suppressed mitochondrial aberrations, excitotoxicity, overaccumulation of metals, and its resultant complications. The immunomodulatory activity of lutein prevents neuroinflammation by hindering NF-κB nuclear translocation, regulation of NIK/IKK, PI3K/AKT, MAPK/ERK, JNK pathways, and ICAM-1 downregulation. Lutein also rescued the dysregulated cholinergic system and resolved memory defects. Along with its neuroprotective properties, lutein also improved neuroplasticity by enabling neurogenesis through increased GAP-43, NCAM, and BDNF levels. ConclusionLutein exhibits strong neuroprotective activities against various NDDs. Though the investigations are in the exploratory phase, this review presents the consolidation of scattered evidence of the neuroprotective properties of lutein and urges its further exploration in clinical studies.

Alleviation of Copper-Induced Hepatotoxicity by Bergenin: Diminution of Oxidative Stress, Inflammation, and Apoptosis via Targeting SIRT1/FOXO3a/NF-κB Axes and p38 MAPK Signaling.

Despite its biological importance, excess copper induces organ damage, especially to the liver. Disruption of critical signaling cascades that control redox status, inflammatory responses, and cellular apoptosis significantly contributes to the copper-induced hepatotoxicity. The present work explored the hepatoprotective ability of bergenin against the copper-induced hepatotoxicity using male Wistar rats as a mammalian model. The results revealed that bergenin suppressed the copper-evoked histopathological changes and hepatocellular necrosis as indicated by decreased activity of the liver enzymes ALT and AST in the sera of the copper-intoxicated rats. It decreased hepatic copper content and the copper-induced oxidative stress as revealed by reduced lipid peroxidation and improved activity of the antioxidant enzymes thioredoxin reductase, glutathione peroxidase, catalase, and superoxide dismutase. Bergenin downregulated the inflammatory cytokines TNF-α and IL-6, and the inflammatory cell infiltration to the liver tissues. Additionally, it inhibited the copper-induced apoptosis as indicated by significant reduction in caspase-3 activity. At the molecular level, bergenin activated the antioxidant transcription factor FOXO3a, inhibited the nuclear translocation of the inflammatory transcription factor NF-κB, and suppressed the inflammatory signaling molecules p38 MAPK and c-Fos. Interestingly, bergenin improved the expression of the anti-apoptotic protein Bcl2 and reduced the pro-apoptotic protein BAX. Bergenin markedly enhanced the expression of the histone deacetylase protein SIRT1 that regulates activity of NF-κB and FOXO3a. Collectively, these findings highlight the alleviating activity of bergenin against the copper-induced hepatotoxicity via controlling oxidative stress, inflammation, and apoptosis potentially through upregulation of SIRT1, activation of FOXO3a along with suppression of NF-κB and p38 MAPK signaling.

Myricetin-loaded SBA-15 silica nanoparticles for enhanced management of pyrexia, pain, and inflammation through modulation of MAPK/NF-κB and COX-2/PGE-2 pathways: Evidence from the biochemical, histological, and metabolomic analysis

Myricetin (MYR) is a natural flavonoid that has several biological functions. However, some of its beneficial effects are diminished due to low water solubility, stability, and bioavailability. Herein, several kinds of silica nanoparticles (MCM-41 and SBA-15) were loaded with MYR to improve its biological activity as an analgesic, antipyretic, and anti-inflammatory component, thereby overcoming its drawbacks. The nanoparticles (MYR@SBA-15) were formulated optimally, transforming MYR into an amorphous state. This transformation was confirmed via several strategies, including differential scanning calorimetry, Fourier transform infrared spectroscopy, and powder x-ray diffraction. As a result, there was a significant enhancement in the solubility and rate of dissolution in water. The anti-inflammatory benefits as an innovative strategy and the underlying mechanism of action of MYR and its SBA-15 silica nanoparticles (MYR@SBA-15) were investigated based on the biochemical, histological, immunohistochemical, and metabolomic assays alongside their antipyretic and analgesic characteristics. Compared to the usage of raw MYR, the administration of MYR@SBA-15 at doses of 25, 50, and 100 mg/kg significantly decreases pain perception by inhibiting the body’s writhing motions induced by acetic acid. Furthermore, it helps regulate increased body temperature caused by baking yeast and effectively stabilizes it. It reduces the release of NO and PGE-2 in a concentration-dependent manner by down-regulating iNOS and COX-2 expression in the inflammatory model. MYR and MYR@SBA-15 also inhibit the nuclear translocation of NF-κB, downregulate the expression of mitogen-activated protein kinases (MAPKs), such as p38, ERK1/2, and JNK protein, and reduce the generation of proinflammatory cytokines, such as TNF-α. In addition, inflammatory cardinal signs like paw edema caused by carrageenan in rats are greatly suppressed by MYR and MYR@SBA-15 treatment when compared to the untreated group. More noteworthy outcomes are shown in the MYR@SBA-15, particularly at a dose of 100 mg/kg. These results of biochemical and immuno-histochemistry suggest that MYR@SBA-15 may be a useful analgesic antipyretic and may also help reduce inflammation by altering MAPKs/NF-κB and COX-2/PGE-2 signaling cascades. Serum metabolomics study demonstrated modifications in various low molecular weight metabolites with arthritis development. These metabolite levels were restored to normal when MYR@SBA-15 was administered via modulating several metabolic pathways, i.e., pyrimidine, energy metabolism, and proteins. Overall, MYR-loaded SBA-15 silica nanoparticles have demonstrated significant promise in enhancing the disturbed metaboloic pathways and providing a substantial capacity to regulate several oxidative stress and inflammatory mediators.

Osthole attenuates asthma-induced airway epithelial cell apoptosis and inflammation by suppressing TSLP/NF-κB-mediated inhibition of Th2 differentiation

ObjectiveThe aim of this study was to investigate the influence of osthole (OS) on asthma-induced airway epithelial cell apoptosis and inflammation by restraining Th2 differentiation through suppressing TSLP/NF-κB.MethodsAn asthma mouse model and an inflammation cell model were constructed with ovalbumin (OVA) and lipopolysaccharide (LPS), respectively. CD4 + T cells were treated with IL-4 to induce Th2 differentiation. Model mice were treated with OS (15,40 mg/kg) for 7 days, and 10 µg/mL OS was added to cell treatment groups. The levels of relevant indices were detected by RT‒qPCR, HE and Masson staining, Western blotting, ELISA and flow cytometry.ResultsIn a mouse asthma model, TSLP expression was elevated, and the NF-κB pathway was activated. Therefore, OS could restrain the apoptosis and inflammation of airway epithelial cells. Downstream mechanistic studies revealed that OS can suppress Th2 differentiation by restraining the level of TSLP and NF-κB nuclear translocation, thus facilitating the proliferation of airway epithelial cells, restraining their apoptosis and inflammation, and alleviating airway inflammation in asthmatic mice.ConclusionOS can inhibit Th2 differentiation by inhibiting the TSLP and NF-κB pathways, which can reduce the apoptosis and inflammation of airway epithelial cells caused by asthma.

Scar matrix drives Piezo1 mediated stromal inflammation leading to placenta accreta spectrum.

Scar tissue formation is a hallmark of wound repair in adults and can chronically affect tissue architecture and function. To understand the general phenomena, we sought to explore scar-driven imbalance in tissue homeostasis caused by a common, and standardized surgical procedure, the uterine scar due to cesarean surgery. Deep uterine scar is associated with a rapidly increasing condition in pregnant women, placenta accreta spectrum (PAS), characterized by aggressive trophoblast invasion into the uterus, frequently necessitating hysterectomy at parturition. We created a model of uterine scar, recapitulating PAS-like invasive phenotype, showing that scar matrix activates mechanosensitive ion channel, Piezo1, through glycolysis-fueled cellular contraction. Piezo1 activation increases intracellular calcium activity and Protein kinase C activation, leading to NF-κB nuclear translocation, and MafG stabilization. This inflammatory transformation of decidua leads to production of IL-8 and G-CSF, chemotactically recruiting invading trophoblasts towards scar, initiating PAS. Our study demonstrates aberrant mechanics of scar disturbs stroma-epithelia homeostasis in placentation, with implications in cancer dissemination.

MiR-146a-5p engineered hucMSC-derived extracellular vesicles attenuate Dermatophagoides farinae-induced allergic airway epithelial cell inflammation.

Allergic asthma is prevalent in children, with Dermatophagoides farinae as a common indoor allergen. Current treatments for allergic airway inflammation are limited and carry risks. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) show promise as a cell-free therapeutic approach. However, the use of engineered MSC-EVs for D. farinae-induced allergic airway epithelial cell inflammation remains unexplored. We generated miR-146a-5p-engineered EVs from human umbilical cord mesenchymal stem cells (hucMSCs) and established D. farinae-induced mouse and human bronchial epithelial cell allergic models. Levels of IL-1β, IL-18, IL-4, IL-5, IL-6, IL-10, IL-33, TNF-α and IgE were detected using ELISA. The relative TRAF6 and IRAK1 mRNA expression was quantified using qPCR assay and the NLRP3, NF-κB, IRAK1 and TRAF6 protein expression was determined using Western blotting. The regulatory effect of IRAK1 and TRAF6 by miR-146a-5p was examined using a dual luciferase reporter assay, and the nuclear translocation of NF-κB p65 into 16-HBE cells was evaluated using immunofluorescence assay. Treatment with hucMSC-EVs effectively reduced allergic inflammation, while miR-146a-5p engineered hucMSC-EVs showed greater efficacy. The enhanced efficacy in alleviating allergic airway inflammation was attributed to the downregulation of IRAK1 and TRAF6 expression, facilitated by miR-146a-5p. This downregulation subsequently led to a decrease in NF-κB nuclear translocation, which in turn resulted in reduced activation of the NLRP3 inflammasome and diminished production of inflammatory cytokines, including IL-6, TNF-α, IL-1β and IL-18. Our study underscores the potential of miR-146a-5p engineered hucMSC-EVs as a cell-free therapeutic strategy for D. farinae-induced allergic airway inflammation, offering a promising avenue for boosting anti-inflammatory responses.

Protective role of cytosolic prion protein against virus infection in prion-infected cells.

Cytosolic PrP has been detected in prion-infected cells and suggested to be involved in the neurotoxicity of prions. Here, we also detected cytosolic PrP in prion-infected cells. We further found that the nuclear translocation of NF-κB was disturbed in prion-infected cells and that the N-terminal potential nuclear translocation signal of PrP expressed in the cytosol disturbed the nuclear translocation of NF-κB. Thus, the N-terminal nuclear translocation signal of cytosolic PrP might play a role in prion neurotoxicity. Prion-like protein aggregates in other protein misfolding disorders, including Alzheimer's disease were reported to play a protective role against various environmental stimuli. We here showed that prion-infected cells were partially resistant to IAV/WSN infection due to the cytosolic PrP-mediated disturbance of the nuclear translocation of NF-κB, which consequently activated NLRP3 inflammasomes after IAV/WSN infection. It is thus possible that prions could also play a protective role in viral infections.

Dihydromyricetin suppresses endothelial NLRP3 inflammasome activation and attenuates atherogenesis by promoting mitophagy

BackgroundNOD-like receptor protein 3 (NLRP3) inflammasome activation is indispensable for atherogenesis. Mitophagy has emerged as a potential strategy to counteract NLRP3 inflammasome activation triggered by impaired mitochondria. Our previous research has indicated that dihydromyricetin, a natural flavonoid, can mitigate NLRP3-mediated endothelial inflammation, suggesting its potential to treat atherosclerosis. However, the precise underlying mechanisms remain elusive. This study sought to investigate whether dihydromyricetin modulates endothelial mitophagy and inhibits NLRP3 inflammasome activation to alleviate atherogenesis, along with the specific mechanisms involved.MethodsApolipoprotein E-deficient mice on a high-fat diet were administered daily oral gavages of dihydromyricetin for 14 weeks. Blood samples were procured to determine the serum lipid profiles and quantify proinflammatory cytokine concentrations. Aortas were harvested to evaluate atherosclerotic plaque formation and NLRP3 inflammasome activation. Concurrently, in human umbilical vein endothelial cells, Western blotting, flow cytometry, and quantitative real-time PCR were employed to elucidate the mechanistic role of mitophagy in the modulation of NLRP3 inflammasome activation by dihydromyricetin.ResultsDihydromyricetin administration significantly attenuated NLRP3 inflammasome activation and vascular inflammation in mice on a high-fat diet, thereby exerting a pronounced inhibitory effect on atherogenesis. Both in vivo and in vitro, dihydromyricetin treatment markedly enhanced mitophagy. This enhancement in mitophagy ameliorated the mitochondrial damage instigated by saturated fatty acids, thereby inhibiting the activation and nuclear translocation of NF-κB. Consequently, concomitant reductions in the transcript levels of NLRP3 and interleukin-1β (IL-1β), alongside decreased activation of NLRP3 inflammasome and IL-1β secretion, were discerned. Notably, the inhibitory effects of dihydromyricetin on the activation of NF-κB and subsequently the NLRP3 inflammasome were determined to be, at least in part, contingent upon its capacity to promote mitophagy.ConclusionThis study suggested that dihydromyricetin may function as a modulator to promote mitophagy, which in turn mitigates NF-κB activity and subsequent NLRP3 inflammasome activation, thereby conferring protection against atherosclerosis.

The negative feedback loop of NF-κB/miR-202-5p/HMGB2 attenuates sepsis induced acute kidney injury

Sepsis represents a primary cause of acute kidney injury (AKI), yet the underlying mechanisms of septic AKI remain poorly understood. Thus, there exists an urgent need for a deeper understanding of its underlying mechanisms and the development of effective therapeutic strategies. Our study reveals a notable induction in microRNA-202-5p (miR-202-5p) levels within renal tubular cells in septic AKI both in vivo and in vitro models. Treatment of renal tubular cells with LPS induced NF-κB activation, which was linked to the induction of miR-202-5p. ChIP assays confirmed NF-κB binding to the miR-202-5p gene promoter upon LPS stimulation. Functionally, miR-202-5p mimics attenuated tubular cell death, kidney injury, and intra-renal inflammatory cytokine production, whereas inhibition of miR-202-5p conferred injurious effects in septic AKI. Notably, miR-202-5p suppressed the expression of High Mobility Group Box 2 (HMGB2) in both in vitro and in vivo septic AKI models. Luciferase microRNA target assays further validated HMGB2 as a direct target of miR-202-5p. Knockdown of HMGB2 inhibits LPS-induced NF-κB activation in septic AKI, as evidenced by HMGB2 siRNA transfection significantly inhibited the nuclear translocation of NF-κB. Together, these findings elucidate the NF-κB/miR-202-5p/HMGB2 negative feedback loop which can attenuate kidney injury by inhibiting renal inflammation in septic AKI. Our findings open new avenues for developing targeted therapies to manage septic AKI effectively.