30 Years of NF-κB: A Blossoming of Relevance to Human Pathobiology

Integrative and comparative genomic analyses of mammalian macrophage responses to intracellular mycobacterial pathogens

Mycobacterium tuberculosis, the causative agent of human tuberculosis (hTB), is a close evolutionary relative of Mycobacterium bovis, which causes bovine tuberculosis (bTB), one of the most damaging infectious diseases to livestock agriculture. Previous studies have shown that the pathogenesis of bTB disease is comparable to hTB disease, and that the bovine and human alveolar macrophage (bAM and hAM, respectively) transcriptomes are extensively reprogrammed in response to infection with these intracellular mycobacterial pathogens. In this study, a multi-omics integrative approach was applied with functional genomics and GWAS data sets across the two primary hosts (Bos taurus and Homo sapiens) and both pathogens (M. bovis and M. tuberculosis). Four different experimental infection groups were used: 1) bAM infected with M. bovis, 2) bAM infected with M. tuberculosis, 3) hAM infected with M. tuberculosis, and 4) human monocyte-derived macrophages (hMDM) infected with M. tuberculosis. RNA-seq data from these experiments 24 h post-infection (24 hpi) was analysed using three computational pipelines: 1) differentially expressed genes, 2) differential gene expression interaction networks, and 3) combined pathway analysis. The results were integrated with high-resolution bovine and human GWAS data sets to detect novel quantitative trait loci (QTLs) for resistance to mycobacterial infection and resilience to disease. This revealed common and unique response macrophage pathways for both pathogens and identified 32 genes (12 bovine and 20 human) significantly enriched for SNPs associated with disease resistance, the majority of which encode key components of the NF-κB signalling pathway and that also drive formation of the granuloma.

Grass carp (Ctenopharyngodon idella) NIK up-regulates the expression of IL-8 by activating the NF-κB canonical pathway

NIK (NF-κB inducing kinase) belongs to the mitogen-activated protein kinase family, which activates NF-κB and plays a vital role in immunology, inflammation, apoptosis, and a series of pathological responses. In NF-κB noncanonical pathway, NIK and IKKα have been often studied in mammals and zebrafish. However, few have explored the relationship between NIK and other subunits of the IKK complex. As a classic kinase in the NF-κB canonical pathway, IKKβ has never been researched with NIK in fish. In this paper, the full-length cDNA sequence of grass carp (Ctenopharyngodon idella) NIK (CiNIK) was first cloned and identified. The expression level of CiNIK in grass carp cells was increased under GCRV stimuli. Under the stimulation of GCRV, poly (I:C), and LPS, the expression of NIK in various tissues of grass carp was also increased. This suggests that CiNIK responds to viral stimuli. To study the relationship between CiNIK and CiIKKβ, we co-transfected CiNIK-FLAG and CiIKKB-GFP into grass carp cells in coimmunoprecipitation and immunofluorescence experiments. The results revealed that CiNIK interacts with CiIKKβ. Besides, the degree of autophosphorylation of CiNIK was enhanced under poly (I:C) stimulation. CiIKKβ was phosphorylated by CiNIK and then activated the activity of p65. The activity change of p65 indicates that NF-κB downstream inflammatory genes will be functioning. CiNIK or CiIKKβ up-regulated the expression of IL-8. It got higher when CiNIK and CiIKKβ coexisted. This paper revealed that NF-κB canonical pathway and noncanonical pathway are not completely separated in generating benefits.

NF-κB signaling in therapy resistance of breast cancer: Mechanisms, approaches, and challenges

Breast cancer is the most common type of cancer and is the second leading cause of cancer-related mortality in women. Chemotherapy, targeted therapy, endocrine therapy, and radiotherapy are all effective in destroying tumor cells, but they also activate the defense and protection systems of cancer cells, leading to treatment resistance. Breast cancer is characterized by a highly inflammatory tumor microenvironment. The NF-κB pathway is essential for connecting inflammation and cancer, as well as for tumor growth and therapy resistance. An increase in NF-κB signaling boosts the growth potential of breast cancer cells and facilitates the spread of tumors to bone, lymph nodes, lungs, and liver. This review focuses on the mechanisms by which chemotherapy, targeted therapy, endocrine therapy, and radiotherapy induce breast cancer resistance through NF-κB signaling. Additionally, we investigate therapeutic regimens, including single agents or in combination with target inhibitors, plant extracts, nanomedicines, and miRNAs, that have been reported in clinical trials, in vivo, and in vitro to reverse resistance. In particular, NF-κB inhibitors combined with tamoxifen were shown to significantly increase the sensitivity of breast cancer cells to tamoxifen. Combination therapy of miRNA-34a with doxorubicin was also found to synergistically inhibit the progression of doxorubicin-resistant breast cancer by inhibiting Notch/NF-κB signaling.

Targeting Nrf2 signaling pathways in the role of bladder cancer: From signal network to targeted therapy

Bladder cancer (BC) is the most common malignancy of the urinary system and often recurs after tumor removal and/or is resistant to chemotherapy. In cancer cells, the activity of the signaling pathway changes significantly, affecting a wide range of cell activities from growth and proliferation to apoptosis, invasion and metastasis. Nrf2 is a transcription factor that plays an important role in cellular defense responses to a variety of cellular stresses. There is increasing evidence that Nrf2 acts as a tumor driver and that it is involved in the maintenance of malignant cell phenotypes. Abnormal expression of Nrf2 has been found to be common in a variety of tumors, including bladder cancer. Over-activation of Nrf2 can lead to DNA damage and the development of bladder cancer, and is also associated with various pathological phenomena of bladder cancer, such as metastasis, angiogenesis, and reduced toxicity and efficacy of therapeutic anticancer drugs to provide cell protection for cancer cells. However, the above process can be effectively inhibited or reversed by inhibiting Nrf2. Therefore, Nrf2 signaling may be a potential targeting pathway for bladder cancer. In this review, we will characterize this signaling pathway and summarize the effects of Nrf2 and crosstalk with other signaling pathways on bladder cancer progression. The focus will be on the impact of Nrf2 activation on bladder cancer progression and current therapeutic strategies aimed at blocking the effects of Nrf2. To better determine how to promote new chemotherapy agents, develop new therapeutic agents, and potential therapeutic targets.

Xiaoer niuhuang qingxin powder alleviates influenza a virus infection by inhibiting the activation of the TLR4/MyD88/NF-κB signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Xiaoer Niuhuang Qingxin Powder (XNQP) is a classic traditional Chinese medicine formula with significant clinical efficacy for treating febrile convulsions and influenza.

AIM OF THE STUDY

This study aims to explore the potential mechanisms of XNQP in combating combating the influenza A virus, providing a theoretical basis for its clinical application.

MATERIALS AND METHODS

The present investigation employed network pharmacology and bioinformatics analysis to determine the TLR4/MyD88/NF-κB signaling pathway as a viable target for XNQP intervention in IAV infection.Subsequently, a mouse model of influenza A virus infection was established, and different doses of XNQP were used for intervention. The protein expression levels of TLR4/MyD88/NF-κB were detected using HE staining, Elisa, immunohistochemistry, immunofluorescence, and western blot.

RESULTS

The results showed that treatment with XNQP after IAV infection reduced the mortality and prolonged the survival time of infected mice. It reduced the release of TNF-α and IFN-γ in the serum and alleviated pathological damage in the lung tissue following infection. Additionally, the levels of TLR4, MyD88, NF-κB, and p-NF-κB P65 proteins were significantly reduced in lung tissue by XNQP. The inhibitory effect of XNQP on the expression of MyD88 and NF-κB was antagonized when TLR4 signaling was overexpressed. Consequently, the expression levels of MyD88, NF-κB, and p-NF-κB P65 were increased in lung tissue. Conversely, the expression levels of the proteins MyD88, NF-κB, and p-NF-κB P65 were downregulated when TLR4 signaling was inhibited.

CONCLUSIONS

XNQP alleviated lung pathological changes, reduced serum levels of inflammatory factors, reduced mortality, and prolonged survival time in mice by inhibiting the overexpression of the TLR4/MyD88/NF-κB signaling pathway in lung tissues after IAV infection.

Biomimetic NO Scavenging Hyaluronic Acid Nanoparticles Enable Targeted Delivery of MTX and Integrated Management of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a complicated chronic disorder of the immune system, featured with severe inflammatory joints, synovium hyperplasia, articular cartilage, and bone damage. In the RA microenvironment, RA-involved cells, overproduced nitric oxide (NO), and pro-inflammatory cytokines are highly interplayed and mutually reinforced, which form a vicious circle and play crucial roles in the formation and progression of RA. To comprehensively break the vicious circle and obtain the maximum benefits, we have developed neutrophil membrane-camouflaged NO scavenging nanoparticles based on an NO-responsive hyaluronic acid derivative for delivery of MTX. These multifunctional nanoparticles (NNO-NPs/MTX), by inheriting the membrane functions of the source cells, possess prolonged circulation and specific localization at the inflamed sites when administrated in the body. Remarkably, NNO-NPs/MTX can neutralize the pro-inflammatory cytokines via the outer membrane receptors, scavenge NO, and be responsively disassociated to release MTX for RA-involved cell regulation and HA for lubrication in the RA sites. In a collagen-induced arthritis mouse model, NNO-NPs/MTX exhibits a significant anti-inflammation effect and effectively alleviates the characteristic RA symptoms such as synovial hyperplasia and cartilage destruction, realizing the synergistic and boosted therapeutic outcome against intractable RA. Thus, NNO-NPs/MTX provides a promising and potent platform to integrately treat RA.

Physiological skin oxygen levels: An important criterion for skin cell functionality and therapeutic approaches

The skin is made up of different layers with various gradients, which maintain a complex microenvironment, particularly in terms of oxygen levels. However, all types of skin cells are cultured in conventional incubators that do not reproduce physiological oxygen levels. Instead, they are cultured at atmospheric oxygen levels, a condition that is far removed from physiology and may lead to the generation of free radicals known to induce skin ageing. This review aims to summarize the current literature on the effect of physiological oxygen levels on skin cells, highlight the shortcomings of current in vitro models, and demonstrate the importance of respecting skin oxygen levels. We begin by clarifying the terminology used about oxygen levels and describe the specific distribution of oxygen in the skin. We review and discuss how skin cells adapt their oxygen consumption and metabolism to oxygen levels environment, as well as the changes that are induced, particularly, their redox state, life cycle and functions. We examine the effects of oxygen on both simple culture models and more complex reconstructed skin models. Finally, we present the implications of oxygen modulation for a more therapeutic approach.

The COP9 signalosome stabilized MALT1 promotes Non-Small Cell Lung Cancer progression through activation of NF-κB pathway

MALT1 has been implicated as an upstream regulator of NF-κB signaling in immune cells and tumors. This study determined the regulatory mechanisms and biological functions of MALT1 in non-small cell lung cancer (NSCLC). In cell culture and orthotopic xenograft models, MALT1 suppression via gene expression interference or protein activity inhibition significantly impaired malignant phenotypes and enhanced radiation sensitivity of NSCLC cells. CSN5, the core subunit of COP9 signalosome, was firstly verified to stabilize MALT1 via disturbing the interaction with E3 ligase FBXO3. Loss of FBXO3 in NSCLC cells reduced MALT1 ubiquitination and promoted its accumulation, which was reversed by CSN5 interference. An association between CSN5/FBXO3/MALT1 regulatory axis and poor prognosis in NSCLC patients was identified. Our findings revealed the detail mechanism of continuous MALT1 activation in NF-κB signaling, highlighting its significance as predictor and potential therapeutic target in NSCLC.

Adipose-derived stem cell exosomes loaded with icariin attenuated M1 polarization of macrophages via inhibiting the TLR4/Myd88/NF-κB signaling pathway

Abnormal macrophage polarization is one of the common pathological bases of various inflammatory diseases. The current research focus involves targeting macrophages to remodel their phenotype as a treatment approach for inflammatory diseases. Notably, exosomes can be delivered to specific types of cells or tissues or inflammatory area to realize targeted drug delivery. Although icariin (ICA) exhibits regulatory potential in macrophage polarization, the practical application of ICA is impeded by its water insolubility, poor permeability, and low bioavailability. Exploiting the inherent advantages of exosomes as natural drug carriers, we introduce a novel drug delivery system-adipose-derived stem cells-exosomes (ADSCs-EXO)-ICA. High-performance liquid chromatography analysis confirmed a loading rate of 92.7 ± 0.01 % for ADSCs-EXO-ICA, indicating the successful incorporation of ICA. As demonstrated by cell counting kit-8 assays, ADSCs-EXO exerted a significantly higher promotion effect on macrophage proliferation. The subsequent experimental results revealed the superior anti-inflammatory effect of ADSCs-EXO-ICA compared to individual treatments with EXO or ICA in the lipopolysaccharide + interferon-gamma-induced M1 inflammation model. Additionally, results from enzyme-linked immunosorbent assay, quantitative polymerase chain reaction, and western blot analyses revealed that ADSCs-EXO-ICA effectively inhibited macrophage polarization toward the M1-type and concurrently promoted polarization toward the M2-type. The underlying mechanism involved the modulation of macrophage polarization through inhibition of the Toll-like receptor 4/myeloid differentiation factor 88/nuclear transcription factor-kappa B signaling pathway, thereby mitigating inflammation. These findings underscore the potential therapeutic value of ADSCs-EXO-ICA as a novel intervention for inflammatory diseases.

S1PR3 inhibition protects against LPS-induced ARDS by inhibiting NF-κB and improving mitochondrial oxidative phosphorylation

BACKGROUND

Inflammation and endothelial barrier dysfunction are the major pathophysiological changes in acute respiratory distress syndrome (ARDS). Sphingosine-1-phosphate receptor 3 (S1PR3), a G protein-coupled receptor, has been found to mediate inflammation and endothelial cell (EC) integrity. However, the function of S1PR3 in ARDS has not been fully elucidated.

METHODS

We used a murine lipopolysaccharide (LPS)-induced ARDS model and an LPS- stimulated ECs model to investigate the role of S1PR3 in anti-inflammatory effects and endothelial barrier protection during ARDS.

RESULTS

We found that S1PR3 expression was increased in the lung tissues of mice with LPS-induced ARDS. TY-52156, a selective S1PR3 inhibitor, effectively attenuated LPS-induced inflammation by suppressing the expression of proinflammatory cytokines and restored the endothelial barrier by repairing adherens junctions and reducing vascular leakage. S1PR3 inhibition was achieved by an adeno-associated virus in vivo and a small interfering RNA in vitro. Both the in vivo and in vitro studies demonstrated that pharmacological or genetic inhibition of S1PR3 protected against ARDS by inhibiting the NF-κB pathway and improving mitochondrial oxidative phosphorylation.

CONCLUSIONS

S1PR3 inhibition protects against LPS-induced ARDS via suppression of pulmonary inflammation and promotion of the endothelial barrier by inhibiting NF-κB and improving mitochondrial oxidative phosphorylation, indicating that S1PR3 is a potential therapeutic target for ARDS.

Transient interactions modulate the affinity of NF-κB transcription factors for DNA

The dimeric nuclear factor kappa B (NF-κB) transcription factors (TFs) regulate gene expression by binding to a variety of κB DNA elements with conserved G:C-rich flanking sequences enclosing a degenerate central region. Toward defining mechanistic principles of affinity regulated by degeneracy, we observed an unusual dependence of the affinity of RelA on the identity of the central base pair, which appears to be noncontacted in the complex crystal structures. The affinity of κB sites with A or T at the central position is ~10-fold higher than with G or C. The crystal structures of neither the complexes nor the free κB DNAs could explain the differences in affinity. Interestingly, differential dynamics of several residues were revealed in molecular dynamics simulation studies, where simulation replicates totaling 148 μs were performed on NF-κB:DNA complexes and free κB DNAs. Notably, Arg187 and Arg124 exhibited selectivity in transient interactions that orchestrated a complex interplay among several DNA-interacting residues in the central region. Binding and simulation studies with mutants supported these observations of transient interactions dictating specificity. In combination with published reports, this work provides insights into the nuanced mechanisms governing the discriminatory binding of NF-κB family TFs to κB DNA elements and sheds light on cancer pathogenesis of cRel, a close homolog of RelA.

Toll-interacting protein is activated by the transcription factor GATA1 and Sp1 to negatively regulate NF-κB and MAPK pathways in the Japanese eel (Anguilla japonica)

Toll-interacting protein (Tollip) serves as a crucial inhibitory factor in the modulation of Toll-like receptor (TLR)-mediated innate immunological responses. The structure and function of Tollip have been well documented in mammals, yet the information in teleost remained limited. This work employed in vitro overexpression and RNA interference in vivo and in vitro to comprehensively examine the regulatory effects of AjTollip on NF-κB and MAPK signaling pathways. The levels of p65, c-Fos, c-Jun, IL-1, IL-6, and TNF-α were dramatically reduced following overexpression of AjTollip, whereas knocking down AjTollip in vivo and in vitro enhanced those genes' expression. Protein molecular docking simulations showed AjTollip interacts with AjTLR2, AjIRAK4a, and AjIRAK4b. A better understanding of the transcriptional regulation of AjTollip is crucial to elucidating the role of Tollip in fish antibacterial response. Herein, we cloned and characterized a 2.2 kb AjTollip gene promoter sequence. The transcription factors GATA1 and Sp1 were determined to be associated with the activation of AjTollip expression by using promoter truncation and targeted mutagenesis techniques. Collectively, our results indicate that AjTollip suppresses the NF-κB and MAPK signaling pathways, leading to the decreased expression of the downstream inflammatory factors, and GATA1 and Sp1 play a vital role in regulating AjTollip expression.

Regulatory roles of miRNA-530 in the post-transcriptional regulation of NF-κB signaling pathway through targeted modulation of IκBα in Sebastesschlegelii

MicroRNAs (miRNAs) are a crucial type of non-coding RNAs involved in post-transcriptional regulation. The playing essential regulatory roles in the NF-κB signaling pathway and modulate the host immune response to diverse pathogens by targeting IκBα. However, the regulatory mechanism of miRNAs in relation with IκBα in Sebastes schlegelii remains unclear. In our study, we identified two copies of IkBα gene in black rockfish (Sebastes schlegelii), namely IkBα1 and IkBα2. Moreover, we have discovered that miRNA-530 can activate the NF-κB signaling pathway by inhibiting the expression of IκBα, thereby inducing the inflammatory response. This project comprehensively investigated the interactive regulatory roles of miRNA-530 in the NF-κB signaling pathway at both cellular and in vivo levels, while also elucidating the regulatory relationships between miRNA-530 and IκBα. In conclusion, our research confirmed that miRNA-530 can target the 3'UTR region of IκBα, resulting in a decrease in the expression of IκBα at the post-transcriptional level and inhibiting its translation. The findings contribute to the understanding of the regulatory network of non-coding RNA in teleosts and its subsequent regulation of the NF-κB signaling pathway by miRNAs.

Exosomes derived from mesenchymal stem cells attenuate NLRP3-related pyroptosis in autoimmune premature ovarian insufficiency via the NF-κB pathway

RESEARCH QUESTION

What is the effect of exosomes derived from bone marrow mesenchymal stem cells (MSC-Exos) on the pyroptosis and recovery of granulosa cells in autoimmune premature ovarian insufficiency (POI)?

DESIGN

In vitro, KGN cells were exposed to interferon-gamma to simulate immune injury. Samples were collected after a 48 h incubation with MSC-Exos (30 μg/ml). The cell viability, secretion of oestrogen and expression of key molecules in pyroptosis and the nuclear factor kappa B (NF-κB) pathway were tested. In vivo, the BALB/c mouse model of autoimmune POI model induced by zona pellucida glycoprotein 3 was used. Fertility testing and sample collection were applied 4 weeks after the ovarian subcapsular injection of MSC-Exos (150 μg for each ovary). Hormone concentration measurements, follicle counting and pyroptotic pathway analyses were conducted for each group.

RESULTS

In vitro, MSC-Exos significantly promoted the proliferation rate and secretion of oestrogen, while at the same time suppressing apoptosis and pyroptosis. In vivo, exosomal treatment normalized the irregular oestrous cycles, rescued the follicular loss and increased the pregnancy rate and number of offspring in POI mice. Elevated serum concentrations of oestrogen and anti-Müllerian hormone, as well as decreased concentrations of FSH and interleukin-1β, were shown. Furthermore, MSC-Exos down-regulated the expression of the NLRP3/Casp1/GSDMD pathway and inhibited activation of the NF-κB pathway.

CONCLUSIONS

These findings demonstrate for the first time that MSC-Exos exert a significant effect on restoring ovarian function in autoimmune POI in vivo and in vitro by suppressing the NLRP3/Casp1/GSDMD pathway and pyroptosis. The NF-κB pathway may contribute to the regulation of NLRP3-related pyroptosis.

Biochemical and histopathological evaluation of systemic and ocular toxicity of favipiravir in rats

Purpose: Favipiravir (FAV) used against COVID-19 is an antiviral drug that causes adverse reactions, such as hyperuricaemia, liver damage, and hematopoetic toxicity. The aim of the study was to investigate the systemic and ocular side-effects of FAV in rats, for the first time.Materials and methods: A total of 18 albino male Wistar rats were used in the study. The rats were divided into 3 groups as the healthy group (HG), the group given 50 mg/kg/day favipiravir (FAV50), and the group given 200 mg/kg/d favipiravir (FAV200). These doses were given to the experimental groups for one week. At the end of the experiment histopathological examinations were performed on the conjunctiva and sclera of the eye. In addition, malondialdehyde (MDA), total glutathione (tGSH), superoxide dismutase (SOD), interleukin-1β (IL-1β), and tumor necrosis factor alpha (TNF-α) levels were measured in blood samples taken from rats. Results: Compared to HG, the MDA (1.37 ± 0.61 vs. 4.82 ± 1.40 µmol/mL), IL-1β (2.52 ± 1.14 vs. 6.67 ± 1.99 pg/mL), and TNF-α levels (3.28 ± 1.42 vs. 8.53 ± 3.06 pg/mL) of the FAV200 group were higher. The levels of tGSH (7.58 ± 1.98 vs. 2.50 ± 0.98 nmol/mL) and SOD (13.63 ± 3.43 vs. 3.81 ± 1.43 U/mL) the FAV200 group were lower than the HG (p < 0.05, for all). The degree of damage to the cornea and sclera of the FAV200 group was quite high according to HG (p < 0.001). Conclusions: FAV can cause damage to rat conjunctiva and sclera by increasing oxidant stress and inflammation at high dose.

AS1411 binds to nucleolin via its parallel structure and disrupts the exos-miRNA-27a-mediated reciprocal activation loop between glioma and astrocytes

The interaction between glioma cells and astrocytes promotes the proliferation of gliomas. Micro-RNAs (miRNAs) carried by astrocyte exosomes (exos) may be involved in this process, but the mechanism remains unclear. The oligonucleotide AS1411, which consists of 26 bases and has a G-quadruplex structure, is an aptamer that targets nucleolin. In this study, we demonstrate exosome-miRNA-27a-mediated cross-activation between astrocytes and glioblastoma and show that AS1411 reduces astrocytes' pro-glioma activity. The enhanced affinity of AS1411 toward nucleolin is attributed to its G-quadruplex structure. After binding to nucleolin, AS1411 inhibits the entry of the NF-κB pathway transcription factor P65 into the nucleus, then downregulates the expression of miRNA-27a in astrocytes surrounding gliomas. Then, AS1411 downregulates astrocyte exosome-miRNA-27a and upregulates the expression of INPP4B, the target gene of miRNA-27a in gliomas, thereby inhibiting the PI3K/AKT pathway and inhibiting glioma proliferation. These results were verified in mouse orthotopic glioma xenografts and human glioma samples. In conclusion, the parallel structure of AS1411 allows it to bind to nucleolin and disrupt the exosome-miRNA-27a-mediated reciprocal activation loop between glioma cells and astrocytes. Our results may help in the development of a novel approach to therapeutic modulation of the glioma microenvironment.

Ubiquitin-specific protease-7 promotes expression of airway mucin MUC5AC via the NF-κB signaling pathway

Chronic obstructive pulmonary disease (COPD) and other respiratory diseases frequently present with airway mucus hypersecretion, which not only affects the patient's quality of life but also poses a constant threat to their life expectancy. Ubiquitin-specific protease 7 (USP7), a deubiquitinating enzyme, affects cell differentiation, tissue growth, and disease development. However, its role in airway mucus hypersecretion induced by COPD remains elusive. In this study, USP7 expression was significantly upregulated in airway epithelial samples from patients with COPD, and USP7 was also overexpressed in mouse lung and human airway epithelial cells in models of airway mucus hypersecretion. Inhibition of USP7 reduced the expression of nuclear factor kappa B (NF-κB), phosphorylated-NF-κB (p-NF-κB), and phosphonated inhibitor of nuclear factor kappa B (p-IκBα), and alleviated the airway mucus hypersecretion in vivo and in vitro. Further research revealed that USP7 stimulated airway mucus hypersecretion through the activation of NF-κB nuclear translocation. In addition, the expression of mucin 5AC (MUC5AC) was suppressed by the NF-κB inhibitor erdosteine. These findings suggest that USP7 stimulates the NF-κB signaling pathway, which promotes airway mucus hypersecretion. This study identifies one of the mechanisms regulating airway mucus secretion and provides a new potential target for its prevention and treatment.

WSB1/2 target chromatin-bound lysine-methylated RelA for proteasomal degradation and NF-κB termination

Proteasome-mediated degradation of chromatin-bound NF-κB is critical in terminating the transcription of pro-inflammatory genes and can be triggered by Set9-mediated lysine methylation of the RelA subunit. However, the E3 ligase targeting methylated RelA remains unknown. Here, we find that two structurally similar substrate-recognizing components of Cullin-RING E3 ligases, WSB1 and WSB2, can recognize chromatin-bound methylated RelA for polyubiquitination and proteasomal degradation. We showed that WSB1/2 negatively regulated a subset of NF-κB target genes via associating with chromatin where they targeted methylated RelA for ubiquitination, facilitating the termination of NF-κB-dependent transcription. WSB1/2 specifically interacted with methylated lysines (K) 314 and 315 of RelA via their N-terminal WD-40 repeat (WDR) domains, thereby promoting ubiquitination of RelA. Computational modeling further revealed that a conserved aspartic acid (D) at position 158 within the WDR domain of WSB2 coordinates K314/K315 of RelA, with a higher affinity when either of the lysines is methylated. Mutation of D158 abolished WSB2's ability to bind to and promote ubiquitination of methylated RelA. Together, our study identifies a novel function and the underlying mechanism for WSB1/2 in degrading chromatin-bound methylated RelA and preventing sustained NF-κB activation, providing potential new targets for therapeutic intervention of NF-κB-mediated inflammatory diseases.

Disruption of TIGAR-TAK1 alleviates immunopathology in a murine model of sepsis

Macrophage-orchestrated inflammation contributes to multiple diseases including sepsis. However, the underlying mechanisms remain to be defined clearly. Here, we show that macrophage TP53-induced glycolysis and apoptosis regulator (TIGAR) is up-regulated in murine sepsis models. When myeloid Tigar is ablated, sepsis induced by either lipopolysaccharide treatment or cecal ligation puncture in male mice is attenuated via inflammation inhibition. Mechanistic characterizations indicate that TIGAR directly binds to transforming growth factor β-activated kinase (TAK1) and promotes tumor necrosis factor receptor-associated factor 6-mediated ubiquitination and auto-phosphorylation of TAK1, in which residues 152-161 of TIGAR constitute crucial motif independent of its phosphatase activity. Interference with the binding of TIGAR to TAK1 by 5Z-7-oxozeaenol exhibits therapeutic effects in male murine model of sepsis. These findings demonstrate a non-canonical function of macrophage TIGAR in promoting inflammation, and confer a potential therapeutic target for sepsis by disruption of TIGAR-TAK1 interaction.

Pristimerin Exerts Pharmacological Effects Through Multiple Signaling Pathways: A Comprehensive Review

Pristimerin, a natural triterpenoid isolated from the plants of southern snake vine and Maidenwood in the family Weseraceae, is anti-inflammatory, insecticidal, antibacterial, and antiviral substance and has been used for its cardioprotective and antitumor effects and in osteoporosis treatment. These qualities explain Pristimerin's therapeutic effects on different types of tumors and other diseases. More and more studies have shown that pristimerin acts in a wide range of biological activities and has shown great potential in various fields of modern and Chinese medicine. While Pristimerin's wide range of pharmacological effects have been widely studied by others, our comprehensive review suggests that its mechanism of action may be through affecting fundamental cellular events, including blocking the cell cycle, inducing apoptosis and autophagy, and inhibiting cell migration and invasion, or through activating or inhibiting certain key molecules in several cell signaling pathways, including nuclear factor κB (NF-κB), phosphatidylinositol 3-kinase/protein kinase B/mammalian-targeted macromycin (PI3K/Akt/mTOR), mitogen-activated protein kinases (MAPKs), extracellular signal-regulated protein kinase 1/2 (ERK1/2), Jun amino-terminal kinase (JNK1/2/3), reactive oxygen species (ROS), wingless/integrin1 (Wnt)/β-catenin, and other signaling pathways. This paper reviews the research progress of Pristimerin's pharmacological mechanism of action in recent years to provide a theoretical basis for the molecular targeting therapy and further development and utilization of Pristimerin. It also provides insights into improved treatments and therapies for clinical patients and the need to explore pristimerin as a potential facet of treatment.

Compound heterozygous mutations in the kinase domain of IKKα lead to immunodeficiency and immune dysregulation

IKKα, encoded by CHUK , is crucial in the non-canonical NF-κB pathway and part of the IKK complex activating the canonical pathway alongside IKKβ. Absence of IKKα cause fetal encasement syndrome in human, fatal in utero, while an impaired IKKα-NIK interaction was reported in a single patient and cause combined immunodeficiency. Here, we describe compound heterozygous variants in the kinase domain of IKKα in a female patient with hypogammaglobulinemia, recurrent lung infections, and Hay-Wells syndrome-like features. We showed that both variants were loss-of-function. Non-canonical NF-κB activation was profoundly diminished in stromal and immune cells while the canonical pathway was partially impaired. Reintroducing wild-type CHUK restored non-canonical NF-κB activation. The patient had neutralizing autoantibodies against type I IFN, akin to non-canonical NF-κB pathway deficiencies. Thus, this is the first case of bi-allelic CHUK mutations disrupting IKKα kinase function, broadening non-canonical NF-κB defect understanding and suggesting IKKα's role in canonical NF-κB target gene expression in human.

Negative feedback systems for modelling NF-κB transcription factor oscillatory activity

Low-dimensional negative feedback systems (NFSs) were developed within a signal flow model to describe the oscillatory activities of NF-κB caused by interactions with its inhibitor IκBα. The NFSs were established as 3rd- and 4th-order linear systems containing unperturbed and perturbed negative feedback (NF) loops with constant or time-varying NF strengths and a feed-forward loop. NF-related analytical solutions to the NFSs representing the time courses of NF-κB and IκBα were determined and their exact mathematical relationship was found. The NFS's parameters were determined to fit the experimental time courses of NF-κB in TNF-α-stimulated embryonic fibroblasts, rela-/- embryonic fibroblasts reconstituted with RelA, C9L cells, GFP-p65 knock-in embryonic fibroblasts and embryogenic fibroblasts lacking Iκβ and IκBε, LPS-stimulated IC-21 macrophages treated or not with DCPA, and anti-IgM-stimulated DT40 B-lymphocytes. The unperturbed and perturbed NFSs describing the above biosystems generated isochronous and non-isochronous solutions, depending on a constant or time-varying NF strength, respectively. The oscillation period of the NF-coupled solutions, the phase difference between them and the time delays in the appearance of cytoplasmic IκBα after stimulation of NF-κB were determined. A significant divergence between the IκBα solutions to the NFSs and the IκBα experimental courses led to a rejection of the NF coupling between NF-κB and IκBα in the above biosystems. It was shown that neither the linearity nor the low dimensionality of the NFSs altered the NF relationship and the divergence between the IκBα solutions to the NFS and IκBα experimental time courses. Although the NF relationship between IκBα and NF-κB was not confirmed in all the experimental data analyzed, delayed negative feedback was found in some cases.

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 2 conditions are poorly understood. In this study, we reveal that both patients with psoriasis and those with rosacea as well as their mouse 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 2 diseases.

FGFR inhibition blocks NF-ĸB-dependent glucose metabolism and confers metabolic vulnerabilities in cholangiocarcinoma

Genomic alterations that activate Fibroblast Growth Factor Receptor 2 (FGFR2) are common in intrahepatic cholangiocarcinoma (ICC) and confer sensitivity to FGFR inhibition. However, the depth and duration of response is often limited. Here, we conduct integrative transcriptomics, metabolomics, and phosphoproteomics analysis of patient-derived models to define pathways downstream of oncogenic FGFR2 signaling that fuel ICC growth and to uncover compensatory mechanisms associated with pathway inhibition. We find that FGFR2-mediated activation of Nuclear factor-κB (NF-κB) maintains a highly glycolytic phenotype. Conversely, FGFR inhibition blocks glucose uptake and glycolysis while inciting adaptive changes, including switching fuel source utilization favoring fatty acid oxidation and increasing mitochondrial fusion and autophagy. Accordingly, FGFR inhibitor efficacy is potentiated by combined mitochondrial targeting, an effect enhanced in xenograft models by intermittent fasting. Thus, we show that oncogenic FGFR2 signaling drives NF-κB-dependent glycolysis in ICC and that metabolic reprogramming in response to FGFR inhibition confers new targetable vulnerabilities.

Single-cell transcriptome revealed dysregulated RNA-binding protein expression patterns and functions in human ankylosing spondylitis

Objective

To explore the expression characteristics and regulatory patterns of RBPs in different immune cell types of AS, and to clarify the potential key role of RBPs in the occurrence and development of AS disease.

Methods

PBMC sample data from scRNA-seq (HC*29, AS*10) and bulk RNA-seq (NC*3, AS*5) were selected for correlation analysis.

Results

(1) Compared with the HC group, the numbers of B, DC (dendritic cells), CD14+ Mono and CD8+ T cells were increased in AS group, while the numbers of platelet (platelets), CD8+ NKT, CD16+ Mono (non-classical monocytes), Native CD4+ T and NK were decreased. (2) Through the analysis of RBP genes in B cells, some RBPs were found to play an important role in B cell differentiation and function, such as DDX3X, SFPQ, SRRM1, UPF2. (3) It may be related to B-cell receptor, IgA immunity, NOD-like receptor and other signaling pathways; Through the analysis of RBP genes in CD8+ T cells, some RBPs that play an important role in the immune regulation of CD8+ T were found, such as EIF2S3, EIF4B, HSPA5, MSL3, PABPC1 and SRSF7; It may be related to T cell receptor, TNF, IL17 and other signaling pathways. (4) Based on bulk RNA-seq, it was found that compared with HC and AS patients, differentially expressed variable splicing genes (RASGs) may play an important role in the occurrence and development of AS by participating in transcriptional regulation, protein phosphorylation and ubiquitination, DNA replication, angiogenesis, intracellular signal transduction and other related pathways.

Conclusion

RBPs has specific expression characteristics in different immune cell types of AS patients, and has important regulatory functions. Its abnormal expression and regulation may be closely related to the occurrence and development of AS.

Senotherapy, cancer, and aging

INTRODUCTION

We aimed to highlight the effects of senotherapy on the prevention and treatment of cancer in older individuals. The aim of senotherapy is to eliminate senescent cells. These cells express the senescence-associated secretory phenotype (SASP). With production of inflammatory cytokines, growth factors, and different type of proteases, the SASP is responsible for aging-associated disability and diseases. All mammalian cells experience senescence. The main agents of aging include fibroblasts and adipose cells. Senescent tumor cells may undergo genomic reprogramming and re-enter cell cycle with a stem cell phenotype.

MATERIALS AND METHODS

We conducted a Medline search for the following key words: senotherapy, senolysis, senomorphic agents. We provide a narrative review of the finding.

RESULTS

Different agents may eliminate senescent cells from cell cultures and murine models. These include metformin, rapamycin, desatinib, quercitin, fisetin, ruloxitinib, and BCL2 inhibitors. A randomized controlled study of metformin in 3,000 patients aged 65-79 without glucose intolerance aiming to establish whether senotherapy may prevent or reverse disability and aging associated diseases, including cancer, is ongoing. Senotherapy prolongs the life span and decreases the incidence of cancer in experimental animal models, as well as delays and reverses disability. Senescent tumor cells are found prior to treatment and after chemotherapy and radiation. These elements may be responsible for tumor recurrence and treatment refractoriness.

DISCUSSION

Senotherapy may have substantial effects on cancer management including decreased incidence and aggressiveness of cancer, improved tolerance of antineoplastic treatment, and prevention of relapse after primary treatment. Senotherapy may ameliorate several complications of cancer chemotherapy.

Ruscogenin Attenuates Ulcerative Colitis in Mice by Inhibiting Caspase-1-Dependent Pyroptosis via the TLR4/NF-κB Signaling Pathway

Inflammatory bowel diseases (IBD) are chronic inflammatory disorders affecting the digestive tract, including ulcerative colitis and Crohn's disease. Ruscogenin, a prominent steroidal sapogenin present in radix ophiopogon japonicus, has shown a protective effect on attenuating the inflammatory response associated with inflammatory diseases, but the efficacy of ruscogenin in IBD remains unclear. The aim of this study is to explore the effect of ruscogenin on intestinal barrier dysfunction and inflammatory responses as well as the underlying mechanism in ulcerative colitis. A dextran sulfate sodium salt (DSS)-induced C57BL/6 mouse colitis model was employed for the in vivo studies, while in vitro experiments were performed in THP-1 cells and human intestinal epithelial cells involved in inducing inflammatory responses and pyroptosis using LPS/nigericin. The results indicated that ruscogenin treatment attenuated the symptoms of ulcerative colitis, reduced the release of inflammatory cytokines and the expression of pyroptosis-associated proteins, and restored the integrity of the intestinal epithelial barrier in colon tissue in mice. Moreover, ruscogenin inhibited LPS/nigericin-induced pyroptosis in THP-1 cells. Mechanically, ruscogenin inhibited NLRP3 inflammasome activation and canonical pyroptosis, at least in part, through the suppression of the TLR4/NF-κB signaling pathway. These findings might provide new insights and a solid foundation for further exploration into the therapeutic potential of ruscogenin in the treatment of IBD.

From periphery to center stage: 50 years of advancements in innate immunity

Over the past 50 years in the field of immunology, something of a Copernican revolution has happened. For a long time, immunologists were mainly concerned with what is termed adaptive immunity, which involves the exquisitely specific activities of lymphocytes. But the other arm of immunity, so-called "innate immunity," had been neglected. To celebrate Cell's 50th anniversary, we have put together a review of the processes and components of innate immunity and trace the seminal contributions leading to the modern state of this field. Innate immunity has joined adaptive immunity in the center of interest for all those who study the body's defenses, as well as homeostasis and pathology. We are now entering the era where therapeutic targeting of innate immune receptors and downstream signals hold substantial promise for infectious and inflammatory diseases and cancer.

Selective Hypoxia-Sensitive Oxomer Formation by FIH Prevents Binding of the NF-κB Inhibitor IκBβ to NF-κB Subunits

Pharmacologic inhibitors of cellular hydroxylase oxygen sensors are protective in multiple preclinical in vivo models of inflammation. However, the molecular mechanisms underlying this regulation are only partly understood, preventing clinical translation. We previously proposed a new mechanism for cellular oxygen sensing: oxygen-dependent, (likely) covalent protein oligomer (oxomer) formation. Here, we report that the oxygen sensor factor inhibiting HIF (FIH) forms an oxomer with the NF-κB inhibitor β (IκBβ). The formation of this protein complex required FIH enzymatic activity and was prevented by pharmacologic inhibitors. Oxomer formation was highly hypoxia-sensitive and very stable. No other member of the IκB protein family formed an oxomer with FIH, demonstrating that FIH-IκBβ oxomer formation was highly selective. In contrast to the known FIH-dependent oxomer formation with the deubiquitinase OTUB1, FIH-IκBβ oxomer formation did not occur via an IκBβ asparagine residue, but depended on the amino acid sequence VAERR contained within a loop between IκBβ ankyrin repeat domains 2 and 3. Oxomer formation prevented IκBβ from binding to its primary interaction partners p65 and c-Rel, subunits of NF-κB, the master regulator of the cellular transcriptional response to pro-inflammatory stimuli. We therefore propose that FIH-mediated oxomer formation with IκBβ contributes to the hypoxia-dependent regulation of inflammation.

Sesquiterpene Lactones Containing an α-Methylene-γ-Lactone Moiety Selectively Down-Regulate the Expression of Tumor Necrosis Factor Receptor 1 by Promoting Its Ectodomain Shedding in Human Lung Adenocarcinoma A549 Cells

Alantolactone is a eudesmane-type sesquiterpene lactone containing an α-methylene-γ-lactone moiety. Previous studies showed that alantolactone inhibits the nuclear factor κB (NF-κB) signaling pathway by targeting the inhibitor of NF-κB (IκB) kinase. However, in the present study, we demonstrated that alantolactone selectively down-regulated the expression of tumor necrosis factor (TNF) receptor 1 (TNF-R1) in human lung adenocarcinoma A549 cells. Alantolactone did not affect the expression of three adaptor proteins recruited to TNF-R1. The down-regulation of TNF-R1 expression by alantolactone was suppressed by an inhibitor of TNF-α-converting enzyme. Alantolactone increased the soluble forms of TNF-R1 that were released into the culture medium as an ectodomain. The structure-activity relationship of eight eudesmane derivatives revealed that an α-methylene-γ-lactone moiety was needed to promote TNF-R1 ectodomain shedding. In addition, parthenolide and costunolide, two sesquiterpene lactones with an α-methylene-γ-lactone moiety, increased the amount of soluble TNF-R1. Therefore, the present results demonstrate that sesquiterpene lactones with an α-methylene-γ-lactone moiety can down-regulate the expression of TNF-R1 by promoting its ectodomain shedding in A549 cells.

The NFκB Dif is required for behavioral and molecular correlates of sleep homeostasis in Drosophila

The nuclear factor binding the κ light chain in B-cells (NFκB) is involved in a wide range of cellular processes including development, growth, innate immunity, and sleep. However, genetic studies of the role of specific NFκB transcription factors in sleep have been limited. Drosophila fruit flies carry three genes encoding NFκB transcription factors, Dorsal, Dorsal Immunity Factor (Dif), and Relish. We previously found that loss of the Relish gene from fat body suppressed daily nighttime sleep, and abolished infection-induced sleep. Here we show that Dif regulates daily sleep and recovery sleep following prolonged wakefulness. Mutants of Dif showed reduced daily sleep and suppressed recovery in response to sleep deprivation. Pan-neuronal knockdown of Dif strongly suppressed daily sleep, indicating that in contrast to Relish, Dif functions from the central nervous system to regulate sleep. Based on the unique expression pattern of a Dif- GAL4 driver, we hypothesized that its effects on sleep were mediated by the pars intercerebralis (PI). While RNAi knock-down of Dif in the PI reduced daily sleep, it had no effect on the recovery response to sleep deprivation. However, recovery sleep was suppressed when RNAi knock-down of Dif was distributed across a wider range of neurons. Induction of the nemuri (nur) antimicrobial peptide by sleep deprivation was reduced in Dif mutants and pan-neuronal over-expression of nur also suppressed the Dif mutant phenotype by significantly increasing sleep and reducing nighttime arousability. Together, these findings indicate that Dif functions from brain to target nemuri and to promote deep sleep.

Truncating NFKB1 variants cause combined NLRP3 inflammasome activation and type I interferon signaling and predispose to necrotizing fasciitis

In monogenic autoinflammatory diseases, mutations in genes regulating innate immune responses often lead to uncontrolled activation of inflammasome pathways or the type I interferon (IFN-I) response. We describe a mechanism of autoinflammation potentially predisposing patients to life-threatening necrotizing soft tissue inflammation. Six unrelated families are identified in which affected members present with necrotizing fasciitis or severe soft tissue inflammations. Exome sequencing reveals truncating monoallelic loss-of-function variants of nuclear factor κ light-chain enhancer of activated B cells (NFKB1) in affected patients. In patients' macrophages and in NFKB1-variant-bearing THP-1 cells, activation increases both interleukin (IL)-1β secretion and IFN-I signaling. Truncation of NF-κB1 impairs autophagy, accompanied by the accumulation of reactive oxygen species and reduced degradation of inflammasome receptor nucleotide-binding oligomerization domain, leucine-rich repeat-containing protein 3 (NLRP3), and Toll/IL-1 receptor domain-containing adaptor protein inducing IFN-β (TRIF), thus leading to combined excessive inflammasome and IFN-I activity. Many of the patients respond to anti-inflammatory treatment, and targeting IL-1β and/or IFN-I signaling could represent a therapeutic approach for these patients.

Alantolactone derivatives inhibit the tumor necrosis factor α-induced nuclear factor κB pathway by a different mechanism from alantolactone

Alantolactone is a eudesmane-type sesquiterpene lactone that exerts various biological effects, including anti-inflammatory activity. In the present study, screening using the RIKEN Natural Products Depository chemical library identified alantolactone derivatives that inhibited the expression of intercellular adhesion molecule-1 (ICAM-1) on human umbilical vein endothelial cells stimulated with proinflammatory cytokines and Toll-like receptor ligands. In human lung adenocarcinoma A549 cells stimulated with tumor necrosis factor-α (TNF-α), six alantolactone derivatives inhibited ICAM-1 expression in a dose-dependent manner and at IC50 values of 13-21 μM, whereas that of alantolactone was 5 μM. Alantolactone possesses an α-methylene-γ-lactone moiety, whereas alantolactone derivatives do not. In the nuclear factor κB (NF-κB) signaling pathway, alantolactone prevented the TNF-α-induced phosphorylation and degradation of the inhibitor of NF-κB α (IκBα) protein, and its downstream signaling pathway. In contrast, alantolactone derivatives neither reduced TNF-α-induced IκBα degradation nor the nuclear translocation of the NF-κB subunit RelA, but inhibited the binding of RelA to the ICAM-1 promoter. The inhibitory activities of alantolactone and alantolactone derivatives were attenuated by glutathione. These results indicate that alantolactone derivatives inhibit the TNF-α-induced NF-κB pathway by a different mechanism from alantolactone.

Nerve growth factor receptor limits inflammation to promote remodeling and repair of osteoarthritic joints

Osteoarthritis (OA) is a painful, incurable disease affecting over 500 million people. Recent clinical trials of the nerve growth factor (NGF) inhibitors in OA patients have suggested adverse effects of NGF inhibition on joint structure. Here we report that nerve growth factor receptor (NGFR) is upregulated in skeletal cells during OA and plays an essential role in the remodeling and repair of osteoarthritic joints. Specifically, NGFR is expressed in osteochondral cells but not in skeletal progenitor cells and induced by TNFα to attenuate NF-κB activation, maintaining proper BMP-SMAD1 signaling and suppressing RANKL expression in mice. NGFR deficiency hyper-activates NF-κB in murine osteoarthritic joints, which impairs bone formation and enhances bone resorption as exemplified by a reduction in subchondral bone and osteophytes. In human OA cartilage, NGFR is also negatively associated with NF-κB activation. Together, this study suggests a role of NGFR in limiting inflammation for repair of diseased skeletal tissues.

Synthesis, Anti-Inflammatory Activities, and Molecular Docking Study of Novel Pyxinol Derivatives as Inhibitors of NF-κB Activation

Pyxinol, an active metabolite of ginsenosides in human hepatocytes, exhibits various pharmacological activities. Here, a series of C-3 modified pyxinol derivatives was designed and virtually screened by molecular docking with the key inflammation-related proteins of the nuclear factor kappa B (NF-κB) pathway. Some of the novel derivatives were synthesized to assess their effects in inhibiting the production of nitric oxide (NO) and mitochondrial reactive oxygen species (MtROS) in lipopolysaccharide-triggered RAW264.7 cells. Derivative 2c exhibited the highest NO and MtROS inhibitory activities with low cytotoxicity. Furthermore, 2c decreased the protein levels of interleukin 1β, tumor necrosis factor α, inducible nitric oxide synthase, and cyclooxygenase 2 and suppressed the activation of NF-κB signaling. Cellular thermal shift assays indicated that 2c could directly bind with p65 and p50 in situ. Molecular docking revealed that 2c's binding to the p65-p50 heterodimer and p50 homodimer was close to their DNA binding sites. In summary, pyxinol derivatives possess potential for development as NF-κB inhibitors.

Activation of the IKK2/NF-κB pathway in VSMCs inhibits calcified vascular stiffness in CKD

IKK2/NF-κB pathway-mediated inflammation in vascular smooth muscle cells (VSMCs) has been proposed to be an etiologic factor in medial calcification and stiffness. However, the role of the IKK2/NF-κB pathway in medial calcification remains to be elucidated. In this study, we found that chronic kidney disease (CKD) induces inflammatory pathways through the local activation of the IKK2/NF-κB pathway in VMSCs associated with calcified vascular stiffness. Despite reducing the expression of inflammatory mediators, complete inhibition of the IKK2/NF-κB pathway in vitro and in vivo unexpectedly exacerbated vascular mineralization and stiffness. In contrast, activation of NF-κB by SMC-specific IκBα deficiency attenuated calcified vascular stiffness in CKD. Inhibition of the IKK2/NF-κB pathway induced cell death of VSMCs by reducing anti-cell death gene expression, whereas activation of NF-κB reduced CKD-dependent vascular cell death. In addition, increased calcification of extracellular vesicles through the inhibition of the IKK2/NF-κB pathway induced mineralization of VSMCs, which was significantly reduced by blocking cell death in vitro and in vivo. This study reveals that activation of the IKK2/NF-κB pathway in VSMCs plays a protective role in CKD-dependent calcified vascular stiffness by reducing the release of apoptotic calcifying extracellular vesicles.

Functional CRISPR screens in T cells reveal new opportunities for cancer immunotherapies

T cells are fundamental components in tumour immunity and cancer immunotherapies, which have made immense strides and revolutionized cancer treatment paradigm. However, recent studies delineate the predicament of T cell dysregulation in tumour microenvironment and the compromised efficacy of cancer immunotherapies. CRISPR screens enable unbiased interrogation of gene function in T cells and have revealed functional determinators, genetic regulatory networks, and intercellular interactions in T cell life cycle, thereby providing opportunities to revamp cancer immunotherapies. In this review, we briefly described the central roles of T cells in successful cancer immunotherapies, comprehensively summarised the studies of CRISPR screens in T cells, elaborated resultant master genes that control T cell activation, proliferation, fate determination, effector function, and exhaustion, and highlighted genes (BATF, PRDM1, and TOX) and signalling cascades (JAK-STAT and NF-κB pathways) that extensively engage in multiple branches of T cell responses. In conclusion, this review bridged the gap between discovering element genes to a specific process of T cell activities and apprehending these genes in the global T cell life cycle, deepened the understanding of T cell biology in tumour immunity, and outlined CRISPR screens resources that might facilitate the development and implementation of cancer immunotherapies in the clinic.

Shaping the future of preclinical development of successful disease-modifying drugs against Alzheimer's disease: a systematic review of tau propagation models

The transcellular propagation of the aberrantly modified protein tau along the functional brain network is a key hallmark of Alzheimer's disease and related tauopathies. Inoculation-based tau propagation models can recapitulate the stereotypical spread of tau and reproduce various types of tau inclusions linked to specific tauopathy, albeit with varying degrees of fidelity. With this systematic review, we underscore the significance of judicious selection and meticulous functional, biochemical, and biophysical characterization of various tau inocula. Furthermore, we highlight the necessity of choosing suitable animal models and inoculation sites, along with the critical need for validation of fibrillary pathology using confirmatory staining, to accurately recapitulate disease-specific inclusions. As a practical guide, we put forth a framework for establishing a benchmark of inoculation-based tau propagation models that holds promise for use in preclinical testing of disease-modifying drugs.

Enterococcus faecium inhibits NF-κB/NLRP3/Caspase-1 signaling pathway to antagonize enterotoxigenic Escherichia coli-mediated inflammatory response

Enterotoxigenic Escherichia coli (ETEC) can cause intestinal inflammation and diarrhea in yaks, which has a negative impact on their economic value. In recent years, probiotics have gained increasing attention as a pure, natural, nontoxic, harmless, and residue-free additive. However, the underlying mechanisms by which probiotics safeguard against ETEC are not completely elucidated. This study aimed to investigate the protective effect of Enterococcus faecium (E. faecium) against ETEC infection in mice through oral gavage. Morphological changes were examined through light microscopy. The expressions of inflammatory cytokines (IL-1β, IL-6, TNF-α, IL-10, NF-κB, and NLRP3), tight junction protein (ZO-1, Claudin-1), and pyroptosis (Caspase-1, Caspase-4, and gasdermin D (GSDMD)) were detected using immunohistochemistry and quantitative real-time PCR. The results indicate that ETEC infection triggers the activation of inflammation-related pathways (NF-κB) and NLRP3 inflammasome, leading to the expression of a large number of inflammatory cytokines. Additionally, the activation of NLRP3 leads to the release of GSDMD activation through Caspase-1, ultimately resulting in inflammatory injury and pyroptosis. Feeding mice E. faecium early resulted in an increase in the expression of tight junction protein, a reduction in inflammatory cytokines, and alleviation of inflammatory injury and pyroptosis in intestinal tissues. Our research indicates that E. faecium has the ability to antagonize ETEC and provide protection to the gastrointestinal mucosa in mice.

Global Interactome Mapping Reveals Pro-tumorigenic Interactions of NF-κB in Breast Cancer

NF-κB pathway is involved in inflammation; however, recent data shows its role also in cancer development and progression, including metastasis. To understand the role of NF-κB interactome dynamics in cancer, we study the complexity of breast cancer interactome in luminal A breast cancer model and its rearrangement associated with NF-κB modulation. Liquid chromatography-mass spectrometry measurement of 160 size-exclusion chromatography fractions identifies 5460 protein groups. Seven thousand five hundred sixty eight interactions among these proteins have been reconstructed by PrInCE algorithm, of which 2564 have been validated in independent datasets. NF-κB modulation leads to rearrangement of protein complexes involved in NF-κB signaling and immune response, cell cycle regulation, and DNA replication. Central NF-κB transcription regulator RELA co-elutes with interactors of NF-κB activator PRMT5, and these complexes are confirmed by AlphaPulldown prediction. A complementary immunoprecipitation experiment recapitulates RELA interactions with other NF-κB factors, associating NF-κB inhibition with lower binding of NF-κB activators to RELA. This study describes a network of pro-tumorigenic protein interactions and their rearrangement upon NF-κB inhibition with potential therapeutic implications in tumors with high NF-κB activity.

Genome-wide CRISPR activation screen identifies JADE3 as an antiviral activator of NF-kB-dependent IFITM3 expression

The innate immune system features a web of interacting pathways that require exquisite regulation. To identify novel nodes in this immune landscape, we conducted a gain-of-function, genome-wide CRISPR activation screen with influenza A virus. We identified both appreciated and novel antiviral genes, including Jade family PHD zinc finger 3 (JADE3) a protein involved in directing the histone acetyltransferase histone acetyltransferase binding to ORC1 complex to modify chromatin and regulate transcription. JADE3 is both necessary and sufficient to restrict influenza A virus infection. Our results suggest a distinct function for JADE3 as expression of the closely related paralogs JADE1 and JADE2 does not confer resistance to influenza A virus infection. JADE3 is required for both constitutive and inducible expression of the well-characterized antiviral gene interferon-induced transmembrane protein 3 (IFITM3). Furthermore, we find JADE3 activates the NF-kB signaling pathway, which is required for the promotion of IFITM3 expression by JADE3. Therefore, we propose JADE3 activates an antiviral genetic program involving NF-kB-dependent IFITM3 expression to restrict influenza A virus infection.

A large deletion in a non-coding regulatory region leads to NFKB1 haploinsufficiency in two adult siblings

Mutations in NFkB pathway genes can cause inborn errors of immunity (IEI), with NFKB1 haploinsufficiency being a significant etiology for common variable immunodeficiency (CVID). Indeed, mutations in NFKB1 are found in 4 to 5% of in European and United States CVID cohorts, respectively; CVID representing almost ¼ of IEI patients in European countries registries. This case study presents a 49-year-old patient with respiratory infections, chronic diarrhea, immune thrombocytopenia, hypogammaglobulinemia, and secondary lymphoma. Comprehensive genetic analysis, including high-throughput sequencing of 300 IEI-related genes and copy number variation analysis, identified a critical 2.6-kb deletion spanning the first untranslated exon and its upstream region. The region's importance was confirmed through genetic markers indicative of enhancers and promoters. The deletion was also found in the patient's brother, who displayed similar but milder symptoms. Functional analysis supported haploinsufficiency with reduced mRNA and protein expression in both patients. This case underscores the significance of copy number variation (CNV) analysis and targeting noncoding exons within custom gene panels, emphasizing the broader genomic approaches needed in medical genetics.

How inflammation dictates diabetic peripheral neuropathy: An enlightening review

BACKGROUND

Diabetic peripheral neuropathy (DPN) constitutes a debilitating complication associated with diabetes. Although, the past decade has seen rapid developments in understanding the complex etiology of DPN, there are no approved therapies that can halt the development of DPN, or target the damaged nerve. Therefore, clarifying the pathogenesis of DPN and finding effective treatment are the crucial issues for the clinical management of DPN.

AIMS

This review is aiming to summary the current knowledge on the pathogenesis of DPN, especially the mechanism and application of inflammatory response.

METHODS

We systematically summarized the latest studies on the pathogenesis and therapeutic strategies of diabetic neuropathy in PubMed.

RESULTS

In this seminal review, the underappreciated role of immune activation in the progression of DPN is scrutinized. Novel insights into the inflammatory regulatory mechanisms of DPN have been unearthed, illuminating potential therapeutic strategies of notable clinical significance. Additionally, a nuanced examination of DPN's complex etiology, including aberrations in glycemic control and insulin signaling pathways, is presented. Crucially, an emphasis has been placed on translating these novel understandings into tangible clinical interventions to ameliorate patient outcomes.

CONCLUSIONS

This review is distinguished by synthesizing cutting-edge mechanisms linking inflammation to DPN and identifying innovative, inflammation-targeted therapeutic approaches.

Echinacea purpurea root extract mitigates hepatotoxicity, genotoxicity, and ultrastructural changes induced by hexavalent chromium via oxidative stress suppression

Environmental and occupational exposure to hexavalent chromium (CrVI) is mostly renowned as a possible hepatotoxic in mammals. Echinacea purpurea (L.) Moench, a phenolic-rich plant, is recurrently used for its therapeutic properties. Therefore, this investigation was done to explore whether E. purpurea (EP) root extract would have any potential health benefits against an acute dose of CrVI-induced oxidative damage and hepatotoxicity. Results revealed that GC-MS analysis of EP root extract has 26 identified components with a significant amount of total phenolic and flavonoid contents. Twenty-four Male Wistar rats were divided into four groups: control, EP (50 mg/kg BW/day for 21 days), CrVI (15 mg/kg BW as a single intraperitoneal dosage), and EP + CrVI, respectively. Rats treated with CrVI displayed a remarkable rise in oxidative stress markers (TBARS, H2O2, PCC), bilirubin, and lactate dehydrogenase activity, and a marked decrease in enzymatic and non-enzymatic antioxidants, transaminases, and alkaline phosphatase activities, and serum protein level. Also, CrVI administration induced apoptosis and inflammation in addition to histological and ultrastructural abnormalities in the liver tissue. The examined parameters were improved significantly in rats pretreated with EP and then intoxicated with CrVI. Conclusively, EP had a potent antioxidant activity and could be used in the modulation of CrVI-induced hepatotoxicity.

A novel quinoline with airway relaxant effects and anti-inflammatory properties

BACKGROUND

In chronic pulmonary diseases characterized by inflammation and airway obstruction, such as asthma and COPD, there are unmet needs for improved treatment. Quinolines is a group of small heterocyclic compounds that have a broad range of pharmacological properties. Here, we investigated the airway relaxant and anti-inflammatory properties of a novel quinoline (RCD405).

METHODS

The airway relaxant effect of RCD405 was examined in isolated airways from humans, dogs, rats and mice. Murine models of ovalbumin (OVA)-induced allergic asthma and LPS-induced airway inflammation were used to study the effects in vivo. RCD405 (10 mg/kg) or, for comparisons in selected studies, budesonide (3 mg/kg), were administered intratracheally 1 h prior to each challenge. Airway responsiveness was determined using methacholine provocation. Immune cell recruitment to bronchi was measured using flow cytometry and histological analyses were applied to investigate cell influx and goblet cell hyperplasia of the airways. Furthermore, production of cytokines and chemokines was measured using a multiplex immunoassay. The expression levels of asthma-related genes in murine lung tissue were determined by PCR. The involvement of NF-κB and metabolic activity was measured in the human monocytic cell line THP-1.

RESULTS

RCD405 demonstrated a relaxant effect on carbachol precontracted airways in all four species investigated (potency ranking: human = rat > dog = mouse). The OVA-specific IgE and airway hyperresponsiveness (AHR) were significantly reduced by intratracheal treatment with RCD405, while no significant changes were observed for budesonide. In addition, administration of RCD405 to mice significantly decreased the expression of proinflammatory cytokines and chemokines as well as recruitment of immune cells to the lungs in both OVA- and LPS-induced airway inflammation, with a similar effect as for budesonide (in the OVA-model). However, the effect on gene expression of Il-4, IL-5 and Il-13 was more pronounced for RCD405 as compared to budesonide. Finally, in vitro, RCD405 reduced the LPS-induced NF-κB activation and by itself reduced cellular metabolism.

CONCLUSIONS

RCD405 has airway relaxant effects, and it reduces AHR as well as airway inflammation in the models used, suggesting that it could be a clinically relevant compound to treat inflammatory airway diseases. Possible targets of this compound are complexes of mitochondrial oxidative phosphorylation, resulting in decreased metabolic activity of targeted cells as well as through pathways associated to NF-κB. However, further studies are needed to elucidate the mode of action.

Mycobacterial Rv1804c binds to the PEST domain of IκBα and activates macrophage-mediated proinflammatory responses

Recognition of the components of Mycobacterium tuberculosis (Mtb) by macrophages is vital for initiating a cascade of host immune responses. However, the recognition of Mtb-secretory proteins by the receptor-independent pathways of the host remains unclear. Rv1804c is a highly conserved secretory protein in Mtb. However, its exact function and underlying mechanism in Mtb infection remain poorly understood. In the present study, we observed that Rv1804c activates macrophage-mediated proinflammatory responses in an IKKα-independent manner. Furthermore, we noted that Rv1804c inhibits mycobacterial survival. By elucidating the underlying mechanisms, we observed that Rv1804c activates IκBα by directly interacting with its PEST domain. Moreover, Rv1804c was enriched in attenuated but not in virulent mycobacteria and associated with the disease process of tuberculosis. Our findings provide an alternative pathway via which a mycobacterial secretory protein activates macrophage-mediated proinflammatory responses. Our study findings may shed light on the prevention and treatment of tuberculosis.

Elevated Kallistatin promotes the occurrence and progression of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide, and the development of non-alcoholic steatohepatitis (NASH) might cause irreversible hepatic damage. Hyperlipidemia (HLP) is the leading risk factor for NAFLD. This study aims to illuminate the causative contributor and potential mechanism of Kallistatin (KAL) mediating HLP to NAFLD. 221 healthy control and 253 HLP subjects, 62 healthy control and 44 NAFLD subjects were enrolled. The plasma KAL was significantly elevated in HLP subjects, especially in hypertriglyceridemia (HTG) subjects, and positively correlated with liver injury. Further, KAL levels of NAFLD patients were significantly up-regulated. KAL transgenic mice induced hepatic steatosis, inflammation, and fibrosis with time and accelerated inflammation development in high-fat diet (HFD) mice. In contrast, KAL knockout ameliorated steatosis and inflammation in high-fructose diet (HFruD) and methionine and choline-deficient (MCD) diet-induced NAFLD rats. Mechanistically, KAL induced hepatic steatosis and NASH by down-regulating adipose triglyceride lipase (ATGL) and comparative gene identification 58 (CGI-58) by LRP6/Gɑs/PKA/GSK3β pathway through down-regulating peroxisome proliferator-activated receptor γ (PPARγ) and up-regulating kruppel-like factor four (KLF4), respectively. CGI-58 is bound to NF-κB p65 in the cytoplasm, and diminishing CGI-58 facilitated p65 nuclear translocation and TNFα induction. Meanwhile, hepatic CGI-58-overexpress reverses NASH in KAL transgenic mice. Further, free fatty acids up-regulated KAL against thyroid hormone in hepatocytes. Moreover, Fenofibrate, one triglyceride-lowering drug, could reverse hepatic steatosis by down-regulating KAL. These results demonstrate that elevated KAL plays a crucial role in the development of HLP to NAFLD and may be served as a potential preventive and therapeutic target.

Characterizing neuroinflammation and identifying prenatal diagnostic markers for neural tube defects through integrated multi-omics analysis

BACKGROUND

Neural Tube Defects (NTDs) are congenital malformations of the central nervous system resulting from the incomplete closure of the neural tube during early embryonic development. Neuroinflammation refers to the inflammatory response in the nervous system, typically resulting from damage to neural tissue. Immune-related processes have been identified in NTDs, however, the detailed relationship and underlying mechanisms between neuroinflammation and NTDs remain largely unclear. In this study, we utilized integrated multi-omics analysis to explore the role of neuroinflammation in NTDs and identify potential prenatal diagnostic markers using a murine model.

METHODS

Nine public datasets from Gene Expression Omnibus (GEO) and ArrayExpress were mined using integrated multi-omics analysis to characterize the molecular landscape associated with neuroinflammation in NTDs. Special attention was given to the involvement of macrophages in neuroinflammation within amniotic fluid, as well as the dynamics of macrophage polarization and their interactions with neural cells at single-cell resolution. We also used qPCR assay to validate the key TFs and candidate prenatal diagnostic genes identified through the integrated analysis in a retinoic acid-induced NTDs mouse model.

RESULTS

Our analysis indicated that neuroinflammation is a critical pathological feature of NTDs, regulated both transcriptionally and epigenetically within central nervous system tissues. Key alterations in gene expression and pathways highlighted the crucial role of STATs molecules in the JAK-STAT signaling pathway in regulating NTDs-associated neuroinflammation. Furthermore, single-cell resolution analysis revealed significant polarization of macrophages and their interaction with neural cells in amniotic fluid, underscoring their central role in mediating neuroinflammation associated with NTDs. Finally, we identified a set of six potential prenatal diagnostic genes, including FABP7, CRMP1, SCG3, SLC16A10, RNASE6 and RNASE1, which were subsequently validated in a murine NTDs model, indicating their promise as prospective markers for prenatal diagnosis of NTDs.

CONCLUSIONS

Our study emphasizes the pivotal role of neuroinflammation in the progression of NTDs and underlines the potential of specific inflammatory and neural markers as novel prenatal diagnostic tools. These findings provide important clues for further understanding the underlying mechanisms between neuroinflammation and NTDs, and offer valuable insights for the future development of prenatal diagnostics.

The Interplay Between Epilepsy and Parkinson's Disease: Gene Expression Profiling and Functional Analysis

The results of many epidemiological studies suggest a bidirectional causality may exist between epilepsy and Parkinson's disease (PD). However, the underlying molecular landscape linking these two diseases remains largely unknown. This study aimed to explore this possible bidirectional causality by identifying differentially expressed genes (DEGs) in each disease as well as their intersection based on two respective disease-related datasets. We performed enrichment analyses and explored immune cell infiltration based on an intersection of the DEGs. Identifying a protein-protein interaction (PPI) network between epilepsy and PD, and this network was visualised using Cytoscape software to screen key modules and hub genes. Finally, exploring the diagnostic values of the identified hub genes. NetworkAnalyst 3.0 and Cytoscape software were also used to construct and visualise the transcription factor-micro-RNA regulatory and co-regulatory networks, the gene-microRNA interaction network, as well as gene-disease association. Based on the enrichment results, the intersection of the DEGs mainly revealed enrichment in immunity-, phosphorylation-, metabolism-, and inflammation-related pathways. The boxplots revealed similar trends in infiltration of many immune cells in epilepsy and Parkinson's disease, with greater infiltration in patients than in controls. A complex PPI network comprising 186 nodes and 512 edges were constructed. According to node connection degree, top 15 hub genes were considered the kernel targets of epilepsy and PD. The area under curve values of hub gene expression profiles confirmed their excellent diagnostic values. This study is the first to analyse the molecular landscape underlying the epidemiological link between epilepsy and Parkinson's disease. The two diseases are closely linked through immunity-, inflammation-, and metabolism-related pathways. This information was of great help in understanding the pathogenesis, diagnosis, and treatment of the diseases. The present results may provide guidance for further in-depth analysis about molecular mechanisms of epilepsy and PD and novel potential targets.