Activation Of NF-κB Signaling Research Articles

Loss of HNRNPU in Skeletal Muscle Increases Intramuscular Infiltration of Ly6C Positive Cells, leading to Muscle Atrophy through Activation of NF-κB Signaling.

Heterogeneous nuclear ribonucleoprotein U (hnRNPU) is known to play multiple biological roles by regulating transcriptional expression, RNA splicing, RNA stability, and chromatin structure in a tissue-dependent manner. The role of hnRNPU in skeletal muscle development and maintenance has not been previously evaluated. In this study, skeletal muscle specific hnRNPU knock out mice is utilized and evaluated skeletal muscle mass and immune cell infiltration through development. By 4 weeks, muscle-specific hnRNPU knockout mice revealed Ly6C+ monocyte infiltration into skeletal muscle, which preceded muscle atrophy. Canonical NF-kB signaling is activated in a myofiber-autonomous manner with hnRNPU repression. Inducible hnRNPU skeletal muscle knockout mice further demonstrated that deletion of hnRNPU in adulthood is sufficient to cause muscle atrophy, suggesting that hnRNPU's role in muscle maintenance is not during development alone. Treatment with salirasib, to inhibit proliferation of immune cells, prevents muscle atrophy in muscle-specific hnRNPU knock out mice, indicating that immune cell infiltration plays causal role in muscle atrophy of hnRNPU knock out mice. Overall, the findings suggest that loss of hnRNPU triggers muscle inflammation and activates NF-κB signaling in a cell-autonomous manner, culminating in muscle atrophy.

Macrophage scavenger receptor-A1 promotes skeletal muscle regeneration after hindlimb ischemia.

Macrophages mediated inflammatory response is crucial for the recovery of skeletal muscle following ischemia. Thus, it's necessary to exploit macrophages based therapeutic targets for ischemic disease. Here, we found mRNA level of SR-A1 was elevated in patients with critical limb ischemia by analysis of gene expression omnibus (GEO) database. Then we investigated the role and the underlined mechanisms of macrophage SR-A1 in a mouse HLI model. Compared with the SR-A1 fl/fl mice, the Lyz Cre/+/SR-A1 flox/flox (SR-A1 ΔMΦ) mice showed significantly lower laser doppler blood flow in the ischemic limb at day 7 after HLI. Consistently, histological analysis exhibited that ischemic limb of SR-A1 ΔMΦ mice displayed more sever and sustained necrotic morphology, inflammation and fibrosis, decreased vessel density and regeneration rate, compared with which of control SR-A1 fl/fl mice. Furthermore, restoration of wild-type myeloid cells to SR-A1 knock-out mice effectively relieved the doppler perfusion in the ischemic limb and restrained skeletal muscle damage 7 days post HLI. In line with in vivo findings, when co-cultivating macrophages with the mouse myoblast line C2C12, SR-A1 -/- bone marrow macrophage significantly inhibited myoblast differentiation in vitro. Mechanically, SR-A1 enhanced skeletal muscle regeneration response to HLI by inhibiting the oncostatin M (OSM) production via suppressed NF-κB signaling activation. These results indicates that SR-A1 is a promising candidate molecule to improve tissue repair and regeneration in peripheral ischemic arterial disease.

Black tea preserves intestinal homeostasis through balancing barriers and microbiota in mice

IntroductionBlack tea, a beverage consumed worldwide, possesses favorable effects on gastrointestinal tract, including nourishing stomach and promoting digestion. Nevertheless, its specific effects on intestinal homeostasis remains inconclusive.MethodsWe applied black tea to mice prior to inducing colitis with DSS and then monitored their body weight and disease activity index (DAI) daily. When sacrificed, we measured intestinal permeability and conducted analyses of mucin and tight junction proteins. We detected inflammatory cytokines, immune cells, and related inflammatory signaling pathways. In addition, the gut microbiota was analyzed through 16S rRNA sequencing, and the concentrations of short-chain fatty acids (SCFAs) were also measured.ResultsThe results showed that black tea-treated group significantly rescued the DSS-disrupted intestinal structure. It reduced the relative abundance of the pathogenic bacterium Turicibacter, while increased the abundance of beneficial bacteria norank_f_Muribaculaceae and restored the contents of SCFAs such as acetate, propionate, and butyrate. It also protected the intestinal barrier by reducing the levels of immune response-related factors (e.g., TNF-α, IL-6, IL-1β) and increasing the expression of tight junction proteins (TJs) (e.g., ZO-1, occludin). Furthermore, black tea exhibited the capacity to suppress the expression of MMP-9 and ICAM-1, as well as to inhibit the activation of NF-κB signaling pathway.DiscussionOur findings provide a theoretical framework that elucidates the mechanisms by which black tea preserves intestinal homeostasis, highlighting its potential as a preventive strategy against intestinal disruptions. This study contributes to the understanding of the dietary effects of black tea on gastrointestinal health.

Proto-oncogene c-Myb potentiates cisplatin resistance of ovarian cancer cells by downregulating lncRNA NKILA and modulating cancer stemness and LIN28A-let7 axis

Ovarian cancer is a major gynecological cancer that has poor prognosis associated mainly to its late diagnosis. Cisplatin is an FDA approved ovarian cancer therapy and even though the therapy is initially promising, the patients mostly progress to resistance against cisplatin. The underlying mechanisms are complex and not very clearly understood. Using two different paired cell lines representing cisplatin-sensitive and the cisplatin-resistant ovarian cancer cells, the ES2 and the A2780 parental and cisplatin-resistant cells, we show an elevated proto-oncogene c-Myb in resistant cells. We further show down-regulated lncRNA NKILA in resistant cells with its de-repression in resistant cells when c-Myb is silenced. NKILA negatively correlates with cancer cell and invasion but has no effect on cellular proliferation or cell cycle. C-Myb activates NF-κB signaling which is inhibited by NKILA. The cisplatin resistant cells are also marked by upregulated stem cell markers, particularly LIN28A and OCT4, and downregulated LIN28A-targeted let-7 family miRNAs. Whereas LIN28A and downregulated let-7s individually de-repress c-Myb-mediated cisplatin resistance, the ectopic expression of let-7s attenuates LIN28A effects, thus underlying a c-Myb-NKILA-LIN28A-let-7 axis in cisplatin resistance of ovarian cancer cells that needs to be further explored for therapeutic intervention.

Mesencephalic astrocyte-derived neurotrophic factor inhibits cervical cancer progression via regulating macrophage phenotype.

Cervical cancer is a common gynecologic malignant tumor, but the critical factors affecting cervical cancer progression are still not well demonstrated. Mesencephalic astrocyte-derived neurotrophic factor (MANF) has been widely recognized as an anti-inflammatory factor to regulate macrophage polarization. In this study, the effect and mechanism of MANF on cervical cancer were preliminarily explored. Kaplan-Meier curve was used to show the overall survival time of the involved cervical cancer patients with high and low MANF expression in cervical cancer tissues. MANF was highly expressed in peritumoral tissues of cervical carcinoma by using immunohistochemistry and western blot. MANF mRNA level was detected by using qRT-PCR. Dual-labeled immunofluorescence showed MANF was mainly expressed in macrophages of cervical peritumoral tissues. Moreover, MANF-silenced macrophages promoted HeLa and SiHa cells survival, migration, invasion and EMT via NF-κB signaling activation. The results of tumor formation in nude mice indicated MANF-silenced macrophages promoted cervical tumor formation in vivo. Our study reveals an inhibitory role of MANF in cervical cancer progression, indicating MANF as a new and valuable therapeutic target for cervical cancer treatment.

MINK1 deficiency stimulates nucleus pulposus cell pyroptosis and exacerbates intervertebral disc degeneration

Intervertebral disc (IVD) degeneration, induced by aging and irregular mechanical strain, is highly prevalent in the elderly population, serving as a leading cause of chronic low back pain and disability. Evolving evidence has revealed the involvement of nucleus pulposus (NP) pyroptosis in the pathogenesis of IVD degeneration, while the precise regulatory mechanisms of NP pyroptosis remain obscure. Misshapen/Nck-interacting kinase (NIK)-related kinase 1 (MINK1), a serine-threonine protein kinase, has the potential to modulate the activation of NLRP3 inflammasome, indicating its pivotal role in governing pyroptosis. In this study, to assess the significance of MINK1 in NP pyroptosis and IVD degeneration, NP tissues from patients with varying degrees of IVD degeneration, and IVD tissues from both aging-induced and lumbar spine instability (LSI) surgery-induced IVD degeneration mouse models, with or without MINK1 ablation, were meticulously evaluated. Our findings indicated a notable decline in MINK1 expression in NP tissues of patients with IVD degeneration and both mouse models as degeneration progresses, accompanied by heightened matrix degradation and increased NP pyroptosis. Moreover, MINK1 ablation led to substantial activation of NP pyroptosis in both mouse models, and accelerating ECM degradation and intensifying the degeneration phenotype in mechanically stress-induced mice. Mechanistically, MINK1 deficiency triggered NF-κB signaling in NP tissues. Overall, our data illustrate an inverse correlation between MINK1 expression and severity of IVD degeneration, and the absence of MINK1 stimulates NP pyroptosis, exacerbating IVD degeneration by activating NF-κB signaling, highlighting a potential innovative therapeutic target in treating IVD degeneration.

LncRNA MTC-p65 Protein Mediates Skin Fibroblast Proliferation in Liaoning Cashmere Goat by Regulating the Nuclear Factor-Kappa B Signaling Pathway.

The aim of this study is to investigate the activation of NF-κB signaling pathway and the regulation of the expression of genes related to chorionic villus growth by the binding of LncRNA MTC (XLOC_005914) and p65 (transcription factor p65 [Capra hircus], XP_017898873.1). In addition, the regulation of LncRNA MTC and p65 binding on the proliferation of Liaoning Cashmere Goat skin fibroblasts is investigated. The upregulation of LncRNA MTC promoted the proliferation of skin fibroblasts, and the NF-κB signaling pathway played an important role in this process. Compared with the negative control (NC group), the expression of TNFα and NFKB2(NF-κB) genes was highly significantly up-regulated (P < 0.001), and NFKBIA(IκBɑ) genes were highly significantly down-regulated (P < 0.01) after LncRNA MTC overexpression (OE group). The expression levels of TNFα and NFκB-P-p65 proteins were upregulated in the OE group; NF-κB-p65 expression levels were upregulated in the nucleus, IκBα expression levels were downregulated in the cytoplasm, and P-IκBα expression levels were upregulated. LncRNA MTC and p65 proteins were co-localized in the cells. Meanwhile, LncRNA MTC and p65 protein showed significant nucleation in the OE group. RNA pull-down and LC-MS/MS verified that p65 protein was indeed an interacting protein of LncRNA MTC. LncRNA MTC binds to p65 protein, upregulates the expression of TNFα protein, nucleates p65 protein, and activates NF-κB signaling pathway to promote the proliferation of skin fibroblasts in Liaoning Cashmere Goat.

Crosstalk between cancer cells and macrophages promotes OSCC cell migration and invasion through a CXCL1/EGF positive feedback loop.

C-X-C motif chemokine ligand 1 (CXCL1) and epithelial growth factor (EGF) are highly secreted by oral squamous cell carcinoma (OSCC) cells and tumor-associated macrophages, respectively. Recent studies have shown that there is intricate "cross-talk" between OSCC cells and macrophages. However, the underlying mechanisms are still poorly elucidated. The expression of CXCL1 was detected by immunohistochemistry in OSCC clinical samples. CXCL1 levels were evaluatedby RT‒PCR and ELISA in an OSCC cell line and a normal epithelial cell line. The expression of EGF was determined by RT‒PCR and ELISA. The effect of EGF on the proliferation of OSCC cells was evaluated by CCK-8 and colony formation assays. The effect of EGF on the migration and invasion ability and epithelial-mesenchymal transition (EMT) of OSCC cells was determined by wound healing, Transwell, RT‒PCR, Western blot and immunofluorescence assays. The polarization of macrophages was evaluated by RT‒PCR and flow cytometry. Western blotting was used to study the molecular mechanism in OSCC. The expression of C-X-C motif chemokine ligand 1 (CXCL1) was higher in the OSCC cell line (Cal27) than in immortalized human keratinocytes (Hacat cells). CXCL1 derived from Cal27 cells upregulates the expression of epithelial growth factor (EGF) in macrophages. Paracrine stimulation mediated by EGF further facilitates the epithelial-mesenchymal transition (EMT) of Cal27 cells and initiates the upregulation of CXCL1 in a positive feedback-manner. Mechanistically, EGF signaling-induced OSCC cell invasion and migration can be ascribed to the activation of NF-κB signaling mediated by the epithelial growth factor receptor (EGFR), as determined by western blotting. OSCC cell-derived CXCL1 can stimulate the M2 polarization of macrophages and the secretion of EGF. Moreover, EGF significantly activates NF-κB signaling and promotes the migration and invasion of OSCC cells in a paracrine manner. A positive feedback loop between OSCC cells and macrophages was formed, contributing to the promotion of OSCC progression.

Poria cocos Attenuated DSS-Induced Ulcerative Colitis via NF-κB Signaling Pathway and Regulating Gut Microbiota.

Ulcerative colitis (UC), as a chronic inflammatory disease, presents a global public health threat. However, the mechanism of Poria cocos (PC) in treating UC remains unclear. Here, LC-MS/MS was carried out to identify the components of PC. The protective effect of PC against UC was evaluated by disease activity index (DAI), colon length and histological analysis in dextran sulfate sodium (DSS)-induced UC mice. ELISA, qPCR, and Western blot tests were conducted to assess the inflammatory state. Western blotting and immunohistochemistry techniques were employed to evaluate the expression of tight junction proteins. The sequencing of 16S rRNA was utilized for the analysis of gut microbiota regulation. The results showed that a total of fifty-two nutrients and active components were identified in PC. After treatment, PC significantly alleviated UC-associated symptoms including body weight loss, shortened colon, an increase in DAI score, histopathologic lesions. PC also reduced the levels of inflammatory cytokines TNF-α, IL-6, and IL-1β, as evidenced by the suppressed NF-κB pathway, restored the tight junction proteins ZO-1 and Claudin-1 in the colon, and promoted the diversity and abundance of beneficial gut microbiota. Collectively, these findings suggest that PC ameliorates colitis symptoms through the reduction in NF-κB signaling activation to mitigate inflammatory damage, thus repairing the intestinal barrier, and regulating the gut microbiota.

ULK1 Mediated Autophagy-Promoting Effects of Rutin-Loaded Chitosan Nanoparticles Contribute to the Activation of NF-κB Signaling Besides Inhibiting EMT in Hep3B Hepatoma Cells.

Liver cancer remains to be one of the leading causes of cancer worldwide. The treatment options face several challenges and nanomaterials have proven to improve the bioavailability of several drug candidates and their applications in nanomedicine. Specifically, chitosan nanoparticles (CNPs) are extremely biodegradable, pose enhanced biocompatibility and are considered safe for use in medicine. CNPs were synthesized by ionic gelation, loaded with rutin (rCNPs) and characterized by ultraviolet-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS) and transmission electron microscopy (TEM). The rCNPs were tested for their cytotoxic effects on human hepatoma Hep3B cells, and experiments were conducted to determine the mechanism of such effects. Further, the biocompatibility of the rCNPs was tested on L929 fibroblasts, and their hemocompatibility was determined. Initially, UV-vis and FTIR analyses indicated the possible loading of rutin on rCNPs. Further, the rutin load was quantitatively measured using Ultra-Performance Liquid Chromatography (UPLC) and the concentration was 88 µg/mL for 0.22 micron filtered rCNPs. The drug loading capacity (LC%) of the rCNPs was observed to be 13.29 ± 0.68%, and encapsulation efficiency (EE%) was 19.55 ± 1.01%. The drug release was pH-responsive as 88.58% of the drug was released after 24 hrs at the lysosomal pH 5.5, whereas 91.44% of the drug was released at physiological pH 7.4 after 102 hrs. The cytotoxic effects were prominent in 0.22 micron filtered samples of 5 mg/mL rutin precursor. The particle size for the rCNPs at this concentration was 144.1 nm and the polydispersity index (PDI) was 0.244, which is deemed to be ideal for tumor targeting. A zeta potential (ζ-potential) value of 16.4 mV indicated rCNPs with good stability. The IC50 value for the cytotoxic effects of rCNPs on human hepatoma Hep3B cells was 9.7 ± 0.19 μg/mL of rutin load. In addition, the increased production of reactive oxygen species (ROS) and changes in mitochondrial membrane potential (MMP) were observed. Gene expression studies indicated that the mechanism for cytotoxic effects of rCNPs on Hep3B cells was due to the activation of Unc-51-like autophagy-activating kinase (ULK1) mediated autophagy and nuclear factor kappa B (NF-κB) signaling besides inhibiting the epithelial-mesenchymal Transition (EMT). In addition, the rCNPs were less toxic on NCTC clone 929 (L929) fibroblasts in comparison to the Hep3B cells and possessed excellent hemocompatibility (less than 2% of hemolysis). The synthesized rCNPs were pH-responsive and possessed the physicochemical properties suitable for tumor targeting. The particles were effectively cytotoxic on Hep3B cells in comparison to normal cells and possessed excellent hemocompatibility. The very low hemolytic profile of rCNPs indicates that the drug could be administered intravenously for cancer therapy.

Chronic Microglia Activation Is Suffcient to Induce Significant Increase in Pulmonary Pressure

Introduction: Microglia, the primary resident immune cells of the brain, can be activated very early in disease. Our previous studies have indicated that microglia activation and neuroinflammation in autonomic brain areas were associated with pulmonary hypertension (PH). Furthermore, we also demonstrated that the attenuation of neuroinflammation by either pharmacological inhibition of microglia with minocycline or genetic disruption of neuro-microglia interaction by CX3CR1 depletion led to protection against pulmonary hypertension. Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) plays a crucial role in controlling inflammatory responses via gene expression regulation. NF-κB signaling in microglia triggers a distinct neuroinflammatory response with increased migration, phagocytosis, and release of proinflammatory cytokines such as IL-6, IL-1β and TNF-α. Thus, in this study we investigated if targeted microglia activation was suffcient to initiate the cascade of events that may contribute to the development of pulmonary hypertension. Study Objective: This study was designed to test the hypothesis that chronic microglia activation is suffcient to induce pulmonary hypertension Methods To evaluate the specific contribution of microglia pro-inflammatory activation to modulate pulmonary pressure, we used a mouse line with inducible expression of the Cre-recombinase directed to the Cx3cr1 promoter crossed with IKKcaflox-flox mice. The breeding scheme CX3CR1creER/+: IKKcaflox-flox allows the Cre-recombination events, as induced by tamoxifen administration, to occur in many myeloid cell types. However, when recombination is followed by at least six weeks of time for the repopulation of cells with high turnover rates, this protocol promotes a relatively selective activation of NF-κB signaling on microglia. First, CX3CR1creER/+:IKKcaflox-flox mice (n=14) were injected with tamoxifen or oil (control) (i.p.) daily at 150 mg/kg body weight for six consecutive days. After 8 weeks, invasive RVSP measurement was performed, and tissues were harvested for following analysis. Briefly, a Millar catheter is inserted into the right ventricle. Ventricle pressures and ECG were recorded and analyzed. PH phenotype also included the measurement of the Fulton index (RV:LV+S) and histological and flow cytometry analyses of lung. Data was collected in two separate experiments with similar results. Results: Activation of NF-κB on microglia was suffcient to induce a slight but significant increase in right ventricular systolic pressure (RVSP), surrogate of pulmonary pressure (RVSP: Tamoxifen: 26.23 ± 0.5861 mmHg; Oil: 23.16 ± 0.4339 mmHg (p = 0.001)), and increased right heart contractility (+dP/dt: Tamoxifen: 1586± 90.18 mmHg/s; Oil: 1250 ± 65.39 mmHg/s (p = 0.0092). Interestingly, activation of NF-κB on microglia also induced a significant increase in lung infiltration of monocytic myeloid-derived suppressor cells (Mo-MDSC, CD11b+Ly6ChiLy6G−) and granulocytic-like MDSCs (PMN-MDSC, CD11b+Ly6Clo Ly6G+). Conclusion: Activation of NF-κB on microglia was suffcient to induce a significant increase in pulmonary pressure and increase lung infiltration of myeloid-derived suppressor cells associated with smooth muscle cell proliferation in pulmonary hypertension. K99 HL165026, R01 HL142776. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Erianin alleviates LPS-induced acute lung injury via antagonizing P-selectin-mediated neutrophil adhesion function

Ethnopharmacological relevanceDendrobium officinale Kimura et Migo, known as "Tiepi Shihu" in traditional Chinese medicine, boasts an extensive history of medicinal use documented in the Chinese Pharmacopoeia. "Shen Nong Ben Cao Jing" records D. officinale as a superior herbal medicine for fortifying "Yin" and invigorating the five viscera. Erianin, a benzidine compound, emerges as a prominent active constituent derived from D. officinale, with the pharmacological efficacy of D. officinale closely linked to the anti-inflammatory properties of erianin. Aim of the studyAcute lung injury (ALI) is a substantial threat to global public health, while P-selectin stands out as a promising novel target for treating acute inflammatory conditions. This investigation aims to explore the therapeutic potential of erianin in ALI treatment and elucidate the underlying mechanisms. Experimental designThe effectiveness of erianin in conferring protection against ALI was investigated through comprehensive histopathological and biochemical analyses of lung tissues and bronchoalveolar lavage fluid (BALF) in an in vivo model of LPS-induced ALI in mice. The impact of erianin on fMLP-induced neutrophil chemotaxis was quantitatively assessed using the Transwell and Zigmond chamber, respectively. To determine the therapeutic target of erianin and elucidate their binding capability, a series of sophisticated assays were employed, including drug affinity responsive target stability (DARTS) assay, cellular thermal shift assay (CETSA), and molecular docking analyses. ResultsErianin demonstrated a significant alleviation of LPS-induced acute lung injury, characterized by reduced total cell and neutrophil counts and diminished total protein contents in BALF. Moreover, erianin exhibited a capacity to decrease proinflammatory cytokine production in both lung tissues and BALF. Notably, erianin effectively suppressed the activation of NF-κB signaling in the lung tissues of LPS- challenged mice; however, it did not exhibit in vitro inhibitory effects on inflammation in LPS-induced human pulmonary microvascular endothelial cells (HPMECs). Additionally, erianin blocked the adhesion and rolling of neutrophils on HPMECs. While erianin did not influence endothelial P-selectin expression or cytomembrane translocation, it significantly reduced the ligand affinity between P-selectin and P-selectin glycoprotein ligand-1 (PSGL-1). ConclusionsErianin inhibits P-selectin-mediated neutrophil adhesion to activated endothelium, thereby alleviating ALI. The present study highlights the potential of erianin as a promising lead for ALI treatment.

Prolonged Antibiotic Use in Gulf War Chronic Multisymptom Illness Induces Renal Fibrosis-Like Pathology Associated with microRNA-21-Mediated PTEN Inhibition

Gulf War veterans afflicted with chronic multisymptom Illness (GWI) often experience unexplained, debilitating symptoms, including microbiome dysbiosis, gastrointestinal and neuroinflammation. Prolonged antibiotic treatments, especially of fluoroquinolone class are commonly employed in these veterans, raising concerns about their potential side effects. To date, no studies have investigated the effects of Gulf War (GW) chemicals- Pyridostigmine bromide (PB) and insecticide, permethrin exposures on renal dysfunction in the veterans. Therefore, this study aimed to investigate the impact of prolonged antibiotic exposure on renal pathology in GWI and to elucidate the underlying molecular mechanisms leading to renal dysfunction. In this study, we used a persistent Gulf War Illness (GWI) mouse model to study the combined effect of prolonged antibiotic regimen involving Neomycin and Enrofloxacin treatment for 5 months (20 weeks). Our results showed that prolonged antibiotic treatment exacerbated renal inflammation leading to elevated levels of pro- inflammatory cytokines and significant activation of NF-κB signaling over Gulf war chemicals treated (GWI) mice (GWI). Further, we hypothesized the involvement of HMGB1 mediated RAGE activation leading to the inflammatory phenotype in the kidneys of GWI+ AB mice. We observed that prolonged antibiotic exposure in GWI- induced mice led to significant increased HMGB1-mediated RAGE activation compared to GWI mice, which was associated with increased TGF-β production in GWI+ AB mice. Furthermore, miR-21, whose expression is reported to be regulated by TGF-β is widely linked to renal fibrosis, was also significantly upregulated in antibiotic-treated GWI-induced mice. This upregulation was associated with decreased PTEN expression, a direct target of miR-21 in GWI+ AB mice over GWI- mice, resulting in the activation of the AKT signaling pathway and increased extracellular matrix (ECM) deposition in GWI+ AB mice. Furthermore, we examined the involvement of AKT signaling activation in the induction of Epithelial-Mesenchymal Transition (EMT) by assessing the immunoreactivity of α-SMA. The renal tissue of GWI+AB mice exhibited an elevated immunoreactivity of α-SMA, suggesting that the cells were undergoing transition from an epithelial to a mesenchymal state. In contrast, GWI- mice displayed no significant expression of α-SMA or increased fibronectin deposition, indicating that exposure to Gulf War chemicals alone was insuffcient to induce renal fibrosis-like pathology. These findings highlight the complex interplay between GWI, antibiotics, and renal pathology, emphasizing that prolonged antibiotic treatment in Gulf War Chronic Multisymptom Illness leads to renal fibrosis like- pathology by activating TGF- β dependent miR-21/ PTEN/ AKT signaling. This study was supported by VA Merit Award I01CX001923-01 awarded to Dr. Saurabh Chatterjee. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

LECs regulate neutrophil clearance through IL-17RC/CMTM4/NF-κB axis at sites of inflammation or infection

The lymphatic system plays a vital role in the regulation of tissue fluid balance and the immune response to inflammation or infection. The effects of lymphatic endothelial cells (LECs) on the regulation of neutrophil migration have not been well studied. In three murine models: imiquimod-induced skin inflammation, S. aureus-induced skin infection, and ligature-induced periodontitis, we show that numerous neutrophils migrate from inflamed or infected tissues to the draining lymph nodes via lymphatic vessels. Moreover, inflamed or infected tissues express a high level of IL-17A and TNF-α, simultaneously with a significant increase in the release of neutrophil attractors, including CXCL1, CXCL2, CXCL3, and CXCL5. Importantly, in vitro stimulation of LECs with IL-17A plus TNF-α synergistically promoted these chemokine secretion. Mechanistically, tetra-transmembrane protein CMTM4 directly binds to IL-17RC in LECs. IL-17A plus TNF-α stimulates CXC chemokine secretion by promoting NF-κB signaling. In contrast, knockdown of CMTM4 abrogates IL-17A plus TNF-α activated NF-κB signaling pathways. Lastly, the local administration of adeno-associated virus for CMTM4 in Prox1-CreERT2 mice, mediating LEC-specific overexpression of CMTM4, promotes the drainage of neutrophils by LECs and alleviates immune pathological responses. Thus, our findings reveal the vital role of LECs-mediated neutrophil attraction and clearance at sites of inflammation or infection.

Rutin encapsulated decellularized earthworm granulation hydrogel promotes angiogenesis in wound healing of diabetic rabbit model by inhibiting TRAF1/NF-κB pathway

Diabetic micro-vasculopathy is induced by accumulation of Reactive Oxygen Species (ROS) which results in delayed wound healing under hyperglycemic conditions. The classical practice of treating diabetic wound includes surgical debridement, hyperbaric oxygen therapy and use of antibiotics to control infection. The therapeutic interventions based on these classical practices have been found ineffective in management of diabetic wound healing and diabetic vasculopathy. Henceforth, engineered biomaterials with anti-oxidant activity have become research hotspots for their high biological activity, due to sustained release of active principles and weak immunogenicity. Based on these postulates, current study was conducted to evaluate diabetic wound healing potential of Rutin encapsulated decellularized earthworm granulation tissue (RdECM) with special reference on angiogenesis. The angiogenetic activity of RdECM was evaluated on cell line under hyperglycemic conditions and we found significant decline in ROS induced Deoxyribonucleic acid (DNA) damage and inhibition of Nuclear factor kappa B (NF-Kβ) pathway with subsequent aggregation of cells in tubular structure. Application of RdECM on diabetic wound resulted in accelerated wound healing, reduction in ROS induced DNA damage and down regulation of TNF receptor associated factor 1 (TRAF1). These changes results in inhibition of TRAF1-mediated NF-κB signal activation and subsequently angiogenesis in hyperglycemic conditions of diabetic wound. These findings support therapeutic utility of RdECM as angiogenetic agent and its potential use against diabetic wound healing.

SERPINB3/B4 Is Increased in Psoriasis and Rosacea Lesions and Has Proinflammatory Effects in Mouse Models of these Diseases

Psoriasis and rosacea are both chronic inflammatory skin disorders resulted from aberrant keratinocyte-immune cell crosstalk, but the common molecular foundations for these two conditions are poorly understood. Here, we reveal that both psoriasis and rosacea patients, as well as their mice models, have significantly elevated expressions of SERPINB3/B4 (members of serine protease inhibitor) in the lesional skin. Skin inflammation in mice that resembles both psoriasis and rosacea is prevented by SERPINB3/B4 deficiency. Mechanistically, we demonstrate that SERPINB3/B4 positively induces NF-κB signaling activation, thereby stimulating disease-characteristic inflammatory chemokines and cytokines production in keratinocytes, and promoting the chemotaxis of CD4+ T cells. Our results suggest that, in keratinocytes, SERPINB3/B4 may be involved in the pathogenesis of both psoriasis and rosacea by stimulating NF-κB signaling, and they indicate a possible treatment overlap between these two diseases.

Circ_PABPC1 promotes the malignancy of gastric cancer through interacting with ILK to activate NF-κB pathway

BackgroundGastric cancer (GC) is a common cancer type with both high incidence and mortality. Recent studies have revealed an important role of circRNA in the development of GC. However, more experiments are needed to reveal the precise molecular mechanisms of circRNA in GC development. MethodsBioinformatics analysis was conducted to predict the potential role of circ_PABPC1 in GC and the target proteins of circ_PABPC1. Quantitative RT-PCR, Western blot and immunohistochemistry assays were conducted to detect the levels of circ_PABPC1, NF-κB p65, NF-κB p65 (Ser536) and ILK. MTT, Edu staining, cell scratch-wound and trans-well assays were carried out to detect cell proliferation, migration and invasion. The interaction between ILK and circ_PABPC1 was confirmed by RNA immunoprecipitation (RIP), RNA pull-down and fluorescence in situ hybridization assays. Genetically modified GC cells were injected into mice to evaluate the tumor growth performance. ResultsThis study found that the high expression of circ_PABPC1 was associated with a poor prognosis of GC. The up-regulation of circ_PABPC1 promoted the proliferation, migration and invasion of GC cells. Circ_PABPC1 bound to ILK protein, thereby preventing the degradation of ILK. ILK mediated the effect of circ_PABPC1 on GC cells through activating NF-κB. Conclusioncirc_PABPC1 promotes the malignancy of GC cells through binding to ILK to activate NF-κB signaling pathway.

The structures of two polysaccharides from Lepidium meyenii and their immunomodulatory effects via activating NF-κB signaling pathway

Lepidium meyenii Walp., also known as the “Peruvian national treasure”, is a popular functional food in the daily lives of Peruvian people due to its bioactive with main polysaccharides. However, studies on polysaccharides isolated from Lepidium meyenii were few. Two new highly heterogeneous polysaccharides, MCP-1a and MCP-2b, were isolated and purified from the tuber of Lepidium meyenii. The structure characterization revealed that MCP-1a primarily consisted of D-Glc and had a molecular weight of 6.6 kDa. Its backbone was composed of 1,4,6-α-D-Glc, while branches feature T-α-L-Ara, 1,5-α-L-Ara, and T-α-D-Glc attached to the O-6 positions. MCP-2b was a rare arabinogalactan with a molecular weight of 49.4 kDa. Interestingly, the backbone of MCP-2b was composed of 1,6-β-D-Gal, 1,3,6-β-D-Gal with a few 1,3-β-D-GlcpA-4-OMe units inserted. Side chains of MCP-2b were mainly composed of 1,3-β-D-Gal, T-β-D-Gal, T-α-L-Ara, 1,5-α-L-Ara, with trace amounts of 1,4-β-D-Glc and T-β-D-Glc. The bioactivity assay results revealed that MCP-1a and MCP-2b increased the release of NO, IL-1β, TNF-α, and IL-6 from RAW 264.7 cells at concentrations ranging from 50 μg/mL to 400 μg/mL. Furthermore, MCP-1a and MCP-2b could promote the expression of key transcription factors (IκB-α, p-IκB-α, p65, and p-p65) in the NF-κB pathway, indicating that MCP-1a and MCP-2b had potential immunomodulatory activities.

TRPV3 promotes sebocyte inflammation via transcriptional modulating TLR2 in acne

Acne is a common chronic inflammatory disease of the pilosebaceous unit. Transient receptor potential vanilloid 3 (TRPV3) is an ion channel that is involved in inflammatory dermatosis development. However, the involvement of TRPV3 in acne-related inflammation remains unclear. Here, we used acne-like mice and human sebocytes to examine the role of TRPV3 in the development of acne. We found that TRPV3 expression increased in the skin lesions of Propionibacterium acnes (P. acnes)-injected acne-like mice and the facial sebaceous glands (SGs) of acne patients. TRPV3 promoted inflammatory cytokines and chemokines secretion in human sebocytes and led to neutrophil infiltration surrounding the SGs in acne lesions, further exacerbating sebaceous inflammation and participating in acne development. Mechanistically, TRPV3 enhanced TLR2 level by promoting transcriptional factor phosphorylated-FOS-like antigen-1 (p-FOSL1) expression and its binding to the TLR2 promoter, leading to TLR2 upregulation and downstream NF-κB signaling activation. Genetic or pharmacological inhibition of TRPV3 both alleviated acne-like skin inflammation in mice via the TLR2-NF-κB axis. Thus, our study revealed the critical role of TRPV3 in sebaceous inflammation and indicated its potential as an acne therapeutic target.

The role of CXCL2-mediated crosstalk between tumor cells and macrophages in Fusobacterium nucleatum-promoted oral squamous cell carcinoma progression

Dysbiosis of the oral microbiota is related to chronic inflammation and carcinogenesis. Fusobacterium nucleatum (Fn), a significant component of the oral microbiota, can perturb the immune system and form an inflammatory microenvironment for promoting the occurrence and progression of oral squamous cell carcinoma (OSCC). However, the underlying mechanisms remain elusive. Here, we investigated the impacts of Fn on OSCC cells and the crosstalk between OSCC cells and macrophages. 16 s rDNA sequencing and fluorescence in situ hybridization verified that Fn was notably enriched in clinical OSCC tissues compared to paracancerous tissues. The conditioned medium co-culture model validated that Fn and macrophages exhibited tumor-promoting properties by facilitating OSCC cell proliferation, migration, and invasion. Besides, Fn and OSCC cells can recruit macrophages and facilitate their M2 polarization. This crosstalk between OSCC cells and macrophages was further enhanced by Fn, thereby amplifying this positive feedback loop between them. The production of CXCL2 in response to Fn stimulation was a significant mediator. Suppression of CXCL2 in OSCC cells weakened Fn’s promoting effects on OSCC cell proliferation, migration, macrophage recruitment, and M2 polarization. Conversely, knocking down CXCL2 in macrophages reversed the Fn-induced feedback effect of macrophages on the highly invasive phenotype of OSCC cells. Mechanistically, Fn activated the NF-κB pathway in both OSCC cells and macrophages, leading to the upregulation of CXCL2 expression. In addition, the SCC7 subcutaneous tumor-bearing model in C3H mice also substantiated Fn’s ability to enhance tumor progression by facilitating cell proliferation, activating NF-κB signaling, up-regulating CXCL2 expression, and inducing M2 macrophage infiltration. However, these effects were reversed by the CXCL2-CXCR2 inhibitor SB225002. In summary, this study suggests that Fn contributes to OSCC progression by promoting tumor cell proliferation, macrophage recruitment, and M2 polarization. Simultaneously, the enhanced CXCL2-mediated crosstalk between OSCC cells and macrophages plays a vital role in the pro-cancer effect of Fn.