Engeletin attenuates the inflammatory response via inhibiting TLR4-NFκB signaling pathway in Crohn's disease-like colitis.

ETHNOPHARMACOLOGICAL RELEVANCE: Smilax glabra rhizome has a long history been used for clinical purposes in traditional Chinese medicinal for treating various inflammatory conditions. Engeletin1 (ENG) is one of the most abundant bioactive compounds found in Smilax glabra rhizome, with anti-inflammatory, antioxidant, and ulcer-preventing activities. AIM OF THE STUDY: The purpose of this study was to investigate the ability of ENG to alleviate inflammatory symptoms and improve epithelial barrier integrity utilize a 2,4,6-trinitrobenzene sulfonic acid2 (TNBS)-induced murine model in Crohn's disease3 (CD)-like colitis, and to characterize the underlying anti-inflammatory mechanisms of action. MATERIALS AND METHODS: A colitis model was established in BALB/c mice and treated with ENG for 7 days. RAW264.7 macrophages were pre-treated with ENG and lipopolysaccharide4 (LPS) stimulation. The mice's weight and colon length were assessed. qPCR and Western blotting were used to analyze gene expression and TLR4-NFκB pathway. Flow cytometry was used to analyze the polarization states of the macrophages. RESULTS: Treatment with ENG was sufficient to significantly alleviate symptoms of inflammation and colonic epithelial barrier integrity in treated mice. Significant inhibition of TNF-α, IL-1ß, and IL-6 expression was observed following ENG treatment in vivo and in vitro. ENG was also determined to be capable of inhibiting the expression of iNOS and CD86, inhibited M1 macrophage polarization in vitro, as well as the TLR4-NFκB signaling pathway. Molecular docking showed a highly stable binding between ENG and TLR4. CONCLUSION: ENG has been proven to alleviate inflammation and ameliorate the damage of epithelial barrier in CD-like colitis. ENG also suppressed the M1 macrophages polarization and the inhibited inflammatory cytokines. TLR4-NFκB signaling pathway, especially TLR4, may be the target of ENG. These data offer a new insight into the therapeutic mechanisms of ENG.

Protein Kinase R (PKR) as a Novel dsRNA Sensor in Antiviral Innate Immunity.

Protein kinase R (PKR), a key double-stranded RNA (dsRNA)-activated sensor, is pivotal for cellular responses to diverse stimuli. This protocol delineates a comprehensive methodological framework employing single luciferase assays, yeast assays, immunoblot assays, and quantitative PCR (qPCR) to discern and validate PKR activities and their downstream impacts on NF-κB-activating signaling pathways. These methodologies furnish a systematic approach to unraveling the role of PKR as a dsRNA sensor and effector in antiviral innate immunity, enabling in-depth analyses of dsRNA sensor activities.

Identifying a Gene Deficiency in the Antiviral Innate Immune Signaling Pathway.

Innate immunity is an important defense barrier for the human body. After viral pathogen-associated molecular patterns (PAMPs) are detected by host-pathogen recognition receptors (PRRs), the associated signaling pathways trigger the activation of the interferon (IFN) regulatory factor (IRF) family members and the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). However, any gene defects among the signaling adaptors will compromise innate immune efficiency. Therefore, investigating genetic defects in the antiviral innate immune signaling pathway is important. We summarize the commonly used research methods related to antiviral immune gene defects and outline the relevant research protocols, which will help investigators study antiviral innate immunity.

Mechanism of inhibition of melanoma by fucoxanthin simulated in vitro digestion products in cell models constructed using human malignant melanoma cells (A375) and keratinocytes (HaCaT).

Recently, the increasing incidence of malignant melanoma has become a major public health concern owing to its poor prognosis and impact on quality of life. Consuming foods with potent antitumor compounds can help prevent melanoma and maintain skin health. Fucoxanthin (FX), a naturally occurring carotenoid found in brown algae, possesses antitumor properties. However, its bioavailability, safety risks, and in vivo effects and mechanisms against melanoma remain unclear. This research focused on evaluating the safety and prospective antimelanoma impact of simulated gastrointestinal digestion products (FX-ID) on HaCaT and A375 cells.The results indicate that FX-ID exerts negative effects on mitochondria in A375 cells, increases Bax expression, releases Cytochrome C, and activates cleaved caspase-3, ultimately promoting apoptosis. Additionally, FX-ID influences the mitogen-activated protein kinase (MAPK) pathway by enhancing cyclooxygenase-2 (COX-2) and nuclear factor kappa B (NF-κB) levels, consequently facilitating apoptosis and inflammation without significantly impacting HaCaT cells. These findings provide insight into inhibitory mechanism of FX-ID against melanoma, guiding the development of functional foods for prevention.

Syzygium cumini (L.) skeels mitigate diabetic nephropathy by regulating Nrf2 pathway and mitocyhondrial dysfunction: In vitro and in vivo studies.

ETHNOPHARMACOLOGICAL PREVALENCE: Hyperglycemia in diabetes increases the generation of advanced glycation end products (AGEs) through non-enzymatic reactions. The interaction between AGEs and their receptors (RAGE) leads to oxidative and inflammatory stress, which plays a pivotal role in developing diabetic nephropathy. Syzygium cumini (SC) L. (DC.) homeopathic preparations viz. 200C, 30C, and mother tincture [MT] are used to treat diabetes. This study aimed to elucidate the regulatory effects of SC preparations (200C, 30C, and MT) on the nuclear factor erythroid 2-related factor 2 (Nrf2) - nuclear factor-κB (NF-κB) pathways and mitochondrial dysfunction in mitigating diabetic nephropathy (DN). MATERIALS AND METHODS: Streptozotocin-induced diabetic rats were treated with SC preparations (200C, 30C, MT; 1:20 dilution in distilled water; 600 µL/kg body weight) and metformin (45 mg/kg body weight) twice daily for 40 days. DN was evaluated through biochemical parameters and histological examination. Renal tissue lysates were analyzed for glycation markers. Protein and gene levels of Nrf2, NF-κB, and mitochondrial dysfunctional signaling were determined via western blotting and RT-qPCR. An immunohistochemical analysis of the kidneys was performed. In vitro, human serum albumin (HSA - 10 mg/ml) was glycated with methylglyoxal (MGO - 55 mM) in the presence of SC preparations (200C, 30C, MT) for eight days. Glycated samples (400 µg/mL) were incubated with renal cells (HEK-293) for 24 h. Further reactive oxygen species production, Nrf2 nuclear translocation, and protein or gene expression of Nrf2 and apoptosis markers were analyzed by western blotting, RT-qPCR, and flow cytometry. Molecular docking of gallic and ellagic acid with the HSA-MGO complex was performed. RESULT: In vivo experiments using streptozotocin-induced diabetic rats treated with SC preparations exhibited improved biochemical parameters, preserved kidney function, and reduced glycation adduct formation in a dose-dependent manner. Furthermore, SC preparations downregulated inflammatory mediators such as RAGE, NF-κB, vascular endothelial growth factor (VEGF), and Tumor necrosis factor α (TNF-α) while upregulating the Nrf2-dependent antioxidant and detoxification pathways. They downregulated B-cell lymphoma 2 (Bcl-2) associated X-protein (BAX), C/EBP homologous protein (CHOP), Dynamin-related protein 1 (DRP1), and upregulated BCL 2 gene expression. Notably, SC preparations facilitated nuclear translocation of Nrf2, leading to the upregulation of antioxidant enzymes and the downregulation of oxidative stress markers. Molecular docking studies revealed favorable interactions between gallic (-5.26 kcal/mol) and ellagic acid (-4.71 kcal/mol) with the HSA-MGO complex. CONCLUSION: SC preparations mitigate renal cell apoptosis and mitochondrial dysfunction through Nrf2-dependent mechanisms.

Piperine, a black pepper compound, induces autophagy and cellular senescence mediated by NF-κB and IL-6 in acute leukemia.

Acute leukemia is characterized by abnormal white blood cell proliferation with rapid onset and severe complications. Natural compounds, which are alternative treatments, are widely used in cancer treatment. Piperine, an alkaloid compound from black pepper, exerts anticancer effects through the cell death signaling pathway. Autophagy and senescence signaling pathways are considered target signaling pathways for cancer treatment. In this study, we investigated the effects of piperine via autophagy and senescence signaling pathways in NB4 and MOLT-4 cells. The MTT assay results demonstrated that piperine significantly decreased the viability of NB4 and MOLT-4 cells. Piperine induced autophagy by increasing LC3, Beclin-1 and ULK1 and decreasing mTOR and NF-κB1 expression in NB4 and MOLT-4 cells. In addition, piperine increased senescence-associated beta-galactosidase fluorescence intensity by increasing p21 and IL-6 expression while decreasing CDK2 expression in NB4 and MOLT-4 cells. In conclusion, our study provides additional information about the induction of autophagy and senescence by piperine in acute leukemia.

Aucklandiae radix targeted PKM2 to alleviate ulcerative colitis: Insights from the photocrosslinking target fishing technique.

BACKGROUND: Inflammatory bowel disease (IBD) is a chronic and relapsing disease marked by chronic tissue inflammation that alters the integrity and function of the gut, seriously impacting patient health and quality of life. Aucklandiae Radix (AR), known as Mu Xiang in Chinese, is a traditional Chinese medicine documented in Chinese Pharmacopoeia with effects of strengthening the intestine and stopping diarrhea. However, the potential of AR in treating intestinal inflammation and its underlying mechanism have yet to be further elucidated. PURPOSE: The objective of this study was to explore the protective effect and the potential mechanism attributable to AR for treating ulcerative colitis (UC). STUDY DESIGN AND METHODS: A murine model of UC was constructed using dextran sulfate sodium (DSS) to examine the therapeutic potential of AR in alleviating inflammation and modulating the immune response. Advanced techniques such as photocrosslinking target fishing technique, click chemistry, Western blot analysis, real-time quantitative PCR, flow cytometry, immunofluorescence, and immunohistochemistry were employed to unveil the therapeutic mechanism of AR for treating IBD. RESULTS: AR decreased disease activity index (DAI) score to alleviate the course of IBD through ameliorating intestinal barrier function in DSS-induced mice. Furthermore, AR suppressed NF-κB and NLRP3 pathways to reduce the release of pro-inflammatory factors interleukin-6 and 1ß (IL-6 and IL-1ß) and tumor necrosis factor α (TNF-α), allowing to alleviate the inflammatory response. Flow cytometry revealed that AR could reduce the accumulation of intestinal macrophages and neutrophils, maintaining intestinal immune balance by regulating the ratio of Treg to Th17 cells. It was worth noting that pyruvate kinase isozyme type M2 (PKM2) served as a potential target of AR using the photocrosslinking target fishing technology, which was further supported by cellular thermal shift assay (CETSA), drug affinity target stability (DARTS), and PKM2 knockdown experiments. CONCLUSION: AR targeted PKM2 to inhibit NF-κB and NLRP3 pathways, thereby modulating the inflammatory response and immunity to alleviate DSS-induced UC. These findings suggested the potential of AR in the treatment of UC and AR as a candidate for developing PKM2 regulators.

Inhibition of Myeloma Cell Function by Cannabinoid-Enriched Product Associated With Regulation of Telomere and TP53.

Multiple myeloma is a hematological cancer caused by the uncontrolled proliferation of abnormal plasma cells in the bone marrow, leading to excessive immunoglobulin production. Our study aimed to examine the anticancer properties of BRF1A, a cannabinoid (CBD)-enriched product, on 2 myeloma cell lines: U266 and ARH-7. We treated U266 and ARH-77 myeloma cells with varying doses of BRF1A and measured the production of IgE and IgG antibodies using ELISA. Cell viability was assessed using trypan blue and CCK-8 assays. We measured the expression of genes related to the production of IgE and IgG antibodies, IgEH, and IgGH. We determined its effect on the expression of telomerase and its phosphorylated form as an indicator of telomere stabilization. Furthermore, we determined its effect on other cancer-related targets such as NF-ĸB, c-Myc, and TP53 in U266 cells using reverse transcription polymerase chain reaction (RT-PCR) and western blotting. BRF1A reduced myeloma cell IgE and IgG production in a time and dose-dependent manner. It also suppressed the expression of p-IκBα, p-NFκB (p65), and total NFκB protein, as well as XBP1u and XBP1s. It increased the gene and protein expression of telomere and hTERT and significantly increased cancer suppressor TP53 gene and p53 protein expression. Additionally, BRF1A decreased the c-Myc gene and protein expression. Our study has shown that a CBD-enriched product can reduce the growth of myeloma cells by suppressing the critical functions of IgE- and IgG-producing cells. This study could help bridge the gap in understanding how cannabinoid-containing products affect cancer, aging, telomere, and cancer-suppressor gene activity.

Basal-to-inflammatory transition and tumor resistance via crosstalk with a pro-inflammatory stromal niche.

Cancer-associated inflammation is a double-edged sword possessing both pro- and anti-tumor properties through ill-defined tumor-immune dynamics. While we previously identified a carcinoma tumor-intrinsic resistance pathway, basal-to-squamous cell carcinoma transition, here, employing a multipronged single-cell and spatial-omics approach, we identify an inflammation and therapy-enriched tumor state we term basal-to-inflammatory transition. Basal-to-inflammatory transition signature correlates with poor overall patient survival in many epithelial tumors. Basal-to-squamous cell carcinoma transition and basal-to-inflammatory transition occur in adjacent but distinct regions of a single tumor: basal-to-squamous cell carcinoma transition arises within the core tumor nodule, while basal-to-inflammatory transition emerges from a specialized inflammatory environment defined by a tumor-associated TREM1 myeloid signature. TREM1 myeloid-derived cytokines IL1 and OSM induce basal-to-inflammatory transition in vitro and in vivo through NF-κB, lowering sensitivity of patient basal cell carcinoma explant tumors to Smoothened inhibitor treatment. This work deepens our knowledge of the heterogeneous local tumor microenvironment and nominates basal-to-inflammatory transition as a drug-resistant but targetable tumor state driven by a specialized inflammatory microenvironment.

Cytosolic Hmgb1 accumulation in mesangial cells aggravates diabetic kidney disease progression via NFκB signaling pathway.

Diabetic kidney disease (DKD) is the predominant type of end-stage renal disease. Increasing evidence suggests thatglomerular mesangial cell (MC) inflammation is pivotal for cell proliferation and DKD progression. However, the exactmechanism of MC inflammation remains largely unknown. This study aims to elucidate the role of inflammatoryfactor high-mobility group box 1 (Hmgb1) in DKD. Inflammatory factors related to DKD progression are screened viaRNA sequencing (RNA-seq). In vivo and in vitro experiments, including db/db diabetic mice model, CCK-8 assay, EdUassay, flow cytometric analysis, Co-IP, FISH, qRT-PCR, western blot, single cell nuclear RNA sequencing (snRNA-seq),are performed to investigate the effects of Hmgb1 on the inflammatory behavior of MCs in DKD. Here, wedemonstrate that Hmgb1 is significantly upregulated in renal tissues of DKD mice and mesangial cells cultured withhigh glucose, and Hmgb1 cytopasmic accumulation promotes MC inflammation and proliferation. Mechanistically,Hmgb1 cytopasmic accumulation is two-way regulated by MC-specific cyto-lncRNA E130307A14Rik interaction andlactate-mediated acetylated and lactylated Hmgb1 nucleocytoplasmic translocation, and accelerates NFκB signalingpathway activation via directly binding to IκBα. Together, this work reveals the promoting role of Hmgb1 on MCinflammation and proliferation in DKD and helps expound the regulation of Hmgb1 cytopasmic accumulation in twoways. In particular, Hmgb1 may be a promising therapeutic target for DKD.

Apocynin alleviates thioacetamide-induced acute liver injury: Role of NOX1/NOX4/NF-κB/NLRP3 pathways.

The liver has a distinctive capacity to regenerate, yet severe acute injury can be life-threatening if not treated appropriately. Inflammation and oxidative stress are central processes implicated in the pathophysiology of acute livery injury. NOX isoforms are important enzymes for ROS generation, NF-κB and NLRP3 activation, its inhibition could be vital in alleviating acute liver injury (ALI). Here in our study, we used apocynin, a natural occurring potent NOX inhibitor, to exploreits potential protective effect against thioacetamide (TAA)-induced ALI through modulating crucial oxidative and inflammatory pathways. Rats were injected once with TAA (500 mg/kg/i.p) and treated with apocynin (10 mg/kg/i.p) twice before TAA challenge. Sera and hepatic tissues were collected for biochemical, mRNA expression, western blot analysis and histopathological assessments. Pretreatment with apocynin improved liver dysfunction evidenced by decreased levels of aminotransferases, ALP, GGT and bilirubin. Apocynin reduced mRNA expression of NOX1 and NOX4 which in turn alleviated oxidative stress, as shown by reduction in MDA and NOx levels, and elevation in GSH levels andcatalase and SOD activities. Moreover, apocynin significantly reduced MPO gene expression. We also demonstrate that apocynin ameliorated inflammation through activating IκBα and suppressing IKKα, IKKß, NF-κBp65 and p-NF-κBp65, IL-6 andTNF-α. Additionally, apocynin potentiated the gene expression of anti-inflammatory IL-10 and reduced levels of hepatic NLRP3, Caspase-1 and IL-1ß. These results suggest that apocynin protects against ALI in association with the inhibition of NOX1 and NOX4 and regulating oxidative and inflammatory pathways.

Perinatal exposure to PBEB aggravates liver injury via macrophage-derived TWEAK in male adult offspring mice under western diet.

Liver injury and inflammation are the most commonly observed adverse outcomes following exposure to penta-brominated flame retardants (penta-BFRs). However, the role of inflammation in the development of liver injury in their alternatives has not yet been explored. Our study aimed to investigate the effects and the underlying mechanism of perinatal exposure to pentabromoethylbenzene (PBEB), a penta-BDE alternative, on liver injury in adult offspring mice under both chow and western diet in later life. Results showed that perinatal exposure to PBEB at 0.2 mg/kg or above led to liver injury in male offspring upon challenge with a western diet, but not in females. Utilizing the Olink immunology panel, our study specifically revealed an upregulation of tumor necrosis factor-related weak inducer of apoptosis (TWEAK) within the livers of male mice. This cytokine was further demonstrated to derive from the secretion by infiltrating macrophages in livers both in vivo and in vitro, which facilitated a shift towards M1 macrophage polarization. TWEAK further activated the hepatic NF-κB and NLRP3 inflammasome pathways, subsequently leading to hepatic pyroptosis in male mice of maternal PBEB exposure. Inhibition of TWEAK signaling mitigated macrophage polarization and inflammasome induction in a co-culture system of macrophages and liver cells. Our findings revealed that perinatal exposure to PBEB precipitated liver injury, partially through an inflammatory pathway mediated by macrophage-derived TWEAK, in male mice offspring under western diet.

Disulfiram attenuates cell and tissue damage and blood‒brain barrier dysfunction after intracranial haemorrhage by inhibiting the classical pyroptosis pathway.

No single treatment significantly reduces the mortality rate and improves neurological outcomes after intracerebral haemorrhage (ICH). New evidence suggests that pyroptosis-specific proteins are highly expressed in the perihaematomal tissues of patients with ICH and that the disulfiram (DSF) inhibits pyroptosis. An ICH model was established in C57BL/6 mice by intracranial injection of collagenase, after which DSF was used to treat the mice. Cell model of ICH was constructed, and DSF was used to treat the cells. HE, TUNEL, Nissl, FJC and IF staining were performed to evaluate the morphology of brain tissues; Western blotting and ELISA were performed to measure the protein expression of NOD-like receptor protein 3 (NLRP3)/Caspase-1/gasdermin D (GSDMD) classical pyroptosis pathway and Toll-likereceptor4 (TLR4)/nuclear factor-kappaB (NF-κB) inflammatory signaling pathway and blood‒brain barrier-associated factoes, and the wet/dry weight method was used to determine the brain water content. The expression of proteins related to the NLRP3/Caspase-1/GSDMD pathway and the TLR4/NF-κB pathway was upregulated in tissues surrounding the haematoma compared with that in control tissues; Moreover, the expression of the blood-brain barrier structural proteins occludin and zonula occludens-1 (ZO-1) was downregulated, and the expression of Aquaporin Protein-4 (AQP4) and matrix metalloprotein 9 (MMP-9) was upregulated. DSF significantly inhibited these changes, reduced the haematoma volume, decreased the brain water content, reduced neuronal death and degeneration and improved neurological function after ICH. ICH activated the classical pyroptosis pathway and TLR4/NF-κB inflammatory pathway, disruped the expression of blood-brain barrier structural proteins, and exacerbated brain injury and neurological dysfunction. DSF inhibited these changes and exerted the therapeutic effects on pathological changes and dysfunction caused by ICH.

Immune system adaptation during gender-affirming testosterone treatment.

Infectious, inflammatory and autoimmune conditions present differently in males and females. SARS-CoV-2 infection in naive males is associated with increased risk of death, whereas females are at increased risk of long COVID1, similar to observations in other infections2. Females respond more strongly to vaccines, and adverse reactions are more frequent3, like most autoimmune diseases4. Immunological sex differences stem from genetic, hormonal and behavioural factors5 but their relative importance is only partially understood6-8. In individuals assigned female sex at birth and undergoing gender-affirming testosterone therapy (trans men), hormone concentrations change markedly but the immunological consequences are poorly understood. Here we performed longitudinal systems-level analyses in 23 trans men and found that testosterone modulates a cross-regulated axis between type-I interferon and tumour necrosis factor. This is mediated by functional attenuation of type-I interferon responses in both plasmacytoid dendritic cells and monocytes. Conversely, testosterone potentiates monocyte responses leading to increased tumour necrosis factor, interleukin-6 and interleukin-15 production and downstream activation of nuclear factor kappa B-regulated genes and potentiation of interferon-γ responses, primarily in natural killer cells. These findings in trans men are corroborated by sex-divergent responses in public datasets and illustrate the dynamic regulation of human immunity by sex hormones, with implications for the health of individuals undergoing hormone therapy and our understanding of sex-divergent immune responses in cisgender individuals.

Specific mode electroacupuncture stimulation opens the blood-brain barrier of the infarcted border zone in rats during MCAO/R recovery via modulation of tight junction protein expression by VEGFA and NF-κB.

The blood-brain barrier (BBB) strictly limits the entry of most exogenous therapeutic drugs into the brain, which brings great challenges to the drug treatment of refractory central diseases, including the treatment of ischemic stroke. Our previous studies have shown that specific mode electroacupuncture stimulation (SMES) can temporarily open the BBB, but with the mechanisms largely unknown. This study explored whether SMES opens the BBB in the infarcted border zone of rats during middle cerebral artery occlusion/reperfusion recovery, and whether this is related to p65 or vascular endothelial growth factor A (VEGFA) modulation of tight junction protein expression through in vivo and in vitro studies. Evans blue, FITC-dextran, mouse-derived nerve growth factor (NGF), and transendothelial electrical resistance values were used to evaluate the permeability of the BBB. Additionally, microvascular endothelial cells and astrocytes were utilized for in vitro study. Immunofluorescence, immunohistochemistry, western blot, and ELISA were employed to assess related protein expression. SMES significantly increased vascular permeability for Evans blue and NGF in the infarcted border zone, and increased the expression of VEGFA by activating p-p65, thereby reducing the expression of tight junction proteins Occludin and ZO-1. Correspondingly, oxygen glucose deprivation/reoxygenation activated p-p65 in and induced VEGFA secretion from astrocytes in vitro. Their conditioned medium reduced the expression of Occludin in bEnd.3 cells and increased the permeability of FITC-dextran. The mechanism of SMES opening infarcted border zone BBB is partly related to its actions on p65, VEGFA, and tight junction proteins.

Glucoraphanin and sulforaphane mitigate TNFα-induced Caco-2 monolayers permeabilization and inflammation.

Intestinal permeabilization is central to the pathophysiology of chronic gut inflammation. This study investigated the efficacy of glucoraphanin (GR), prevalent in cruciferous vegetables, particularly broccoli, and its derivative sulforaphane (SF), in inhibiting tumor necrosis factor alpha (TNFα)-induced Caco-2 cell monolayers inflammation and permeabilization through the regulation of redox-sensitive events. TNFα binding to its receptor led to a rapid increase in oxidant production and subsequent elevation in the mRNA levels of NOX1, NOX4, and Duox2. GR and SF dose-dependently mitigated both these short- and long-term alterations in redox homeostasis. Downstream, GR and SF inhibited the activation of the redox-sensitive signaling cascades NF-κB (p65 and IKK) and MAPK ERK1/2, which contribute to inflammation and barrier permeabilization. GR (1 µM) and SF (0.5-1 µM) prevented TNFα-induced monolayer permeabilization and the associated reduction in the levels of the tight junction (TJ) proteins occludin and ZO-1. Both GR and SF also mitigated TNFα-induced increased mRNA levels of the myosin light chain kinase, which promotes TJ opening. Molecular docking suggests that although GR is mostly not absorbed, it could interact with extracellular and membrane sites in NOX1. Inhibition of NOX1 activity by GR would mitigate TNFα receptor downstream signaling and associated events. These findings support the concept that not only SF, but also GR, could exert systemic health benefits by protecting the intestinal barrier against inflammation-induced permeabilization, in part by regulating redox-sensitive pathways. GR has heretofore not been viewed as a biologically active molecule, but rather, the benign precursor of highly active SF. The consumption of GR and/or SF-rich vegetables or supplements in the diet may offer a means to mitigate the detrimental consequences of intestinal permeabilization, not only in disease states but also in conditions characterized by chronic inflammation of dietary and lifestyle origin.

PDCD4 promotes inflammation/fibrosis by activating the PPAR­Î³/NF­κB pathway in mouse atrial myocytes.

Fibrosis is the basis of structural remodeling in atrial fibrillation (AF), during which inflammation is crucial. Programmed cell death factor 4 (PDCD4) is a newly identified inflammatory gene, with unknown mechanisms of action in AF. The present study aimed to elucidate the effects of PDCD4 on the inflammation and structural remodeling of atrial myocytes. For this purpose, a PDCD4 overexpression plasmid (oePDCD4) and PDCD4 small interfering (si)RNA (siPDCD4) were used to modulate PDCD4 expression in mouse atrial myocytes (HL­1 cells). The expression of PDCD4 was detected using reverse transcription­quantitative PCR and western blot analysis. The optimal drug concentrations of peroxisome proliferator­activated receptor γ (PPARγ) agonist (pioglitazone hydrochloride), NF­κB inhibitor (CBL0137), PPARγ inhibitor (GW9962) and NF­κB agonist (betulinic acid) were screened using a Cell Counting Kit­8 assay. The levels of inflammatory factors were detected using enzyme­linked immunosorbent assays, the expression levels of fibrosis­related proteins and NF­κB subunits were detected using western blot analysis, and the expression of phosphorylated (p­)p65/p65 was detected using immunofluorescence staining. The results revealed that PDCD4 overexpression increased the levels of fibrotic factors (collagen I, collagen III, fibronectin, α­smooth muscle actin and matrix metalloproteinase 2), pro­inflammatory cytokines (IFN­Î³, IL­6, IL­17A and TNF­α) and p­p65, whereas it reduced the levels of anti­inflammatory cytokines (IL­4) in HL­1 cells. Additionally, treatment with the PPARγ agonist and NF­κB inhibitor reversed the levels of fibrotic­, pro­inflammatory and anti­inflammatory factors in oePDCD4­HL­1 cells. By contrast, PDCD4 silencing exerted the opposite effects on fibrotic factors, pro­inflammatory cytokines, anti­inflammatory cytokines and p­p65. In addition, treatment with the PPARγ inhibitor and NF­κB agonist reversed the levels of fibrotic­, pro­inflammatory and anti­inflammatory factors in siPDCD4­HL­1 cells. In conclusion, the present study demonstrated that PDCD4 may induce inflammation and fibrosis by activating the PPARγ/NF­κB signaling pathway, thereby promoting the structural remodeling of atrial myocytes in AF.

ACE2 alleviates sepsis-induced cardiomyopathy through inhibiting M1 macrophage via NF-κB/STAT1 signals.

Angiotensin-converting enzyme 2 (ACE2), a crucial element of the renin-angiotensin system (RAS), metabolizes angiotensin II into Ang (1-7), which then combines with the Mas receptor (MasR) to fulfill its protective role in various diseases. Nevertheless, the involvement of ACE2 in sepsis-induced cardiomyopathy (SIC) is still unexplored. In this study, our results revealed that CLP surgery dramatically impaired cardiac function accompanied with disruption of the balance between ACE2-Ang (1-7) and ACE-Ang II axis in septic heart tissues. Moreover, ACE2 knockin markedly alleviated sepsis induced RAS disorder, cardiac dysfunction and improved survival rate in mice, while ACE2 knockout significantly exacerbates these outcomes. Adoptive transfer of bone marrow cells and in vitro experiments showed the positive role of myeloid ACE2 by mitigating oxidative stress, inflammatory response, macrophage polarization and cardiomyocyte apoptosis by blocking NF-κB and STAT1 signals. However, the beneficial impacts were nullified by MasR antagonist A779. Collectively, these findings showed that ACE2 alleviated SIC by inhibiting M1 macrophage via activating the Ang (1-7)-MasR axis, highlight that ACE2 might be a promising target for the management of sepsis and SIC patients.

Lawsonia intracellularis regulates nuclear factor-κB signalling pathway during infection.

Lawsonia intracellularis is the etiological agent of proliferative enteropathy (PE) in pigs, horses and wide range of mammals. Little is known about the role of innate immune response during L. intracellularis infection. In this study, we investigated the nuclear factor-κB (NF-κB)-regulated immune response against infection of a clinical strain Dkp23 and a live-attenuated Enterisol vaccine strain in PK-15 cells. We found that expression of NF-κB target genes TNF-α, IFN-γ, IL-6 and IL-8 were modulated during the course of infection. At 5 dpi, there was a significant increase in p65 NF-κB activation, including protein nuclear translocation and phosphorylation, synchronous with the induction of IL-6, IFN-γ and IL-8 expression in L. intracellularis infected cells, especially for Enterisol vaccine strain-infected cells. This result suggests that NF-κB signalling level is induced when L. intracellularis bacterial load peaks at 5 dpi. The induction of pro-inflammatory cytokines expression is consistent with the decreased viability of L. intracellularis-infected cells especially that of the vaccine strain. There were no significant changes in NF-κB signalling between vaccine and Dkp23 infection in PK-15 cells, except for moderate levels of differences in NF-κB target genes expression which might be a reflection of differences in intracellular bacterial load. Overall, the data presented here indicate a correlation between the induction of NF-κB signalling and the L. intracellularis bacterial load in PK-15 cells.

Specific cell subclusters of dental pulp stem cells respond to distinct pathogens through the ROS pathway.

Introduction: Microbial pathogens invade various human organs, including the oral cavity. Candida albicans (C.a) and Streptococcus mutans (S.m) served respectively as representative oral pathogenic fungi and bacteria to stimulate dental pulp stem cells (DPSCs) and to screen the DPSC subcluster that specifically responded to fungal infection. Methods: DPSCs were obtained from the impacted third molars of six healthy subjects. Then, cells were mixed and divided into three samples, two of which were stimulated with C.a and S.m, respectively; the third sample was exposed to cell medium only (Ctrl). Single-cell mRNA sequencing analysis of treated DPSCs was performed. Results: DPSCs were composed of four major clusters of which one, DPSC.7, exhibited unique changes compared to those of other subclusters. The DPSC.7 cell percentage of the C.a sample was twice those of the Ctrl and S.m samples. DPSC.7 cells expressed genes associated with the response to reactive oxygen species (ROS) response. DPSC.7 subgroup cells established characteristic aggregation under the stimulation of different pathogens in UMAP. The MAPK/ERK1/2 and NF-κB pathways were up-regulated, DUSP1/5/6 expressions were suppressed, FOS synthesis was activated, the immune-related pathway was induced, and the levels of cytokines, including IL-6 and CCL2, were up-regulated in DPSC.7 cells when stimulated with C.a. Conclusions: Our study analyzed the cellular and molecular properties of DPSCs infected by oral fungi and bacteria with single-cell RNA sequencing. A subcluster of DPSCs responded specifically to infections with different pathogens, activating the MAPK and NF-κB pathways to induce immune responses via the ROS pathway. This suggests novel treatment strategies for fungal infections.