NF-κB Signal Transduction Pathway Research Articles

Syndecan-3 inhibits LPS-induced Inflammation of Bovine Mammary Epithelial Cells through the NF-κB Signal Transduction Pathway

In mastitis, excessive inflammation caused by lipopolysaccharide (LPS) is an important factor leading to mammary tissue damage. Therefore, exploring the regulatory factors that can inhibit the widespread inflammation caused by LPS is crucial. Syndecan-3 (SDC3) has been found to play an active role in anti-inflammatory infection by inhibiting leukocyte adhesion, reducing the accumulation of inflammatory products, such as reactive oxygen species, and competing with chemokines; however, the role and regulatory mechanism of SDC3 in mastitis remains unknown. Therefore, this study aimed to reveal the effect of SDC3 on LPS-induced inflammation in bovine mammary epithelial cells (BMECs) and explore its possible molecular mechanisms. First, we constructed a BMEC inflammatory model. It was found that cells stimulated with 10 μg/mL LPS for 24 h strongly induced the expression of inflammatory cytokines and had no toxic effect on cells, which was the best condition to simulate the BMECs inflammatory response in vitro. Subsequently, we used overexpression and RNAi interference, Real Time Quantitative PCR (RT-qPCR), and Western blot assays to explore the effects of SDC3 on LPS-induced inflammatory factors and their mechanisms. The results showed that overexpression of SDC3 could inhibit the transcriptional levels of inflammatory cytokines IL-6, IL-1β, and TNFα induced by LPS and inhibit the activation of the NF-κB inflammatory pathway by inhibiting the expression of NF-κB p50 and p-IκBα and promoting the expression of IκBα. Our results suggest that SDC3 inhibits the LPS-induced inflammatory response of BMECs through the NF-κB pathway, in which NF-κB p50 may be an important target of SDC3. These findings lay the foundation for elucidating the molecular regulatory mechanisms of dairy cow mastitis.

Research on the mechanism of shengxian and jinshuiliujun decoction in treating silicosis based on network pharmacology

Objective: To explore the active ingredients of shengxian and jinshuiliujun decoction with the method of network pharmacology, and to verify the experimental mechanism of its treatment of silicosis. Methods: In May 2023, the active ingredients and targets of drugs in shengxian and jinshuiliujun decoction were obtained through the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) database. The target of silicosis disease was screened by databases such as Genecards, Disease Gene Network (DisGeNET), Comparative Toxicogenomics Database (CTD), etc. The screened drug targets and disease targets were intersected to obtain the target set of shengxian and jinshuiliujun decoction for the treatment of silicosis. Protein-protein interaction (PPI) network analysis was performed on the target set through STRING database, and core target genes were screened. GO enrichment analysis and KEGG pathway analysis of intersection genes were performed based on Metascape database, and molecular docking verification of key components and targets of shengxian and jinshuiliujun decoction was carried out. Twenty-four adult male SD rats with SPF grade were randomly divided into control group, model group and TCM intervention group, with 8 rats in each group. The dust-stained rat model was prepared by non-tracheal exposure of 1 ml silica suspension (50 mg/ml) in one go, and TCM intervention group was given shengxian and jinshuiliujun decoction[6 g/ (kg·d) ] on the second day. The CT of the lungs of each group was observed 28 days after the dust-stained rat model. Paraffin sections of rat lung tissues were prepared and stained with Hematoxylin-Eosin (HE) and Masson. Western blot was used to verify the expression of core target-related proteins in rat lung tissues after the intervention of shengxian and jinshuiliujun decoction for 28 days, and the differences in protein expression between groups were compared by one-way analysis of variance. Results: A total of 205 active ingredients and 3345 active compounds were selected from shengxian and jinshuiliujun decoction, corresponding to 281 targets, among which 240 targets were related to silicosis. Serine/threonine kinase 1 (AKT1), tumor protein p53 (TP53), tumor necrosis factor (TNF) and interleukin (IL) 6 may be the key targets of shengxian and jinshuiliujun decoction in the treatment of silicosis. Through enrichment analysis, 30 GO entries and 20 potential signaling pathways were screened according to P-value, including nuclear factor κB (NF-κB), mitogen-activated protein kinase (MAPK) and cancer signaling pathways. Molecular docking showed that the active compounds of shengxian and jinshuiliujun decoction had good binding with the core target proteins, and the strongest binding properties were beta-sitosterol and TNF-α (-10.45 kcal/mol). In animal experiments, the inflammatory infiltration and fibrosis of lung tissue of rats in TCM intervention group were significantly improved. Compared with control group, the levels of TNF-α, IL-1β, IL-6 and NF-κB in lung tissue of model group were significantly increased (P<0.05). Compared with model group, the lung injury of rats in TCM intervention group was significantly improved, and the expressions of TNF-α, IL-1β, IL-6 and NF-κB were significantly decreased (P<0.05) . Conclusion: Shengxian and jinshuiliujun decoction in the treatment of silicosis may play an anti-fibrosis role by inhibiting the NF-κB signal transduction pathway mediated by inflammatory factors such as TNF-α and IL-1β, which provides a reference for further exploring the material basis and mechanism of its action.

CLL Cell-Derived Exosomes Impair Immune Function and Normal Hematopoiesis in CLL

CLL is characterized by immune and hematopoietic abnormalities such as T-cell dysfunction, hypogammaglobulinemia, increased levels of inflammatory cytokines, aberrant monocyte polarity, anemia, neutropenia, and low-grade bone marrow fibrosis. As a result, CLL patients become susceptible to increased rates of infection and/or second neoplasms. Exosomes are nanovesicles that participate in bidirectional communication between neoplastic cells and their microenvironment. Using electron microscopy, we found that CLL cells produce and release CD19 +/CD5 +exosomes, and in agreement with other investigators, we detected high levels of CLL cell-derived exosomes in the plasma of patients with CLL. By using bead-assisted flow cytometry, we found that at least 50% of circulating extracellular vesicles are CLL cell-derived exosomes, identified as CD63 +/CD41a - particles co-expressing CD19 +/CD5 +, whereas only a small proportion of CLL patients' plasma-derived exosomes expressed T-cell or endothelial cell surface markers. Furthermore, we found a positive correlation between levels of CLL cell-derived exosomes in the plasma of patients with CLL and the patients' peripheral white blood cell counts, indicating that CLL cells are the primary source of circulating exosomes. To investigate the effects of CLL cell-derived exosomes, we conducted an analysis of CLL cells and CLL cell-derived exosomes from a cohort of 78 previously untreated patients. To identify the molecular profiles of CLL cell-derived exosomes, we analyzed their RNA transcripts using RNA-seq and qRT-PCR. Our data revealed that CLL cell-derived exosomes expressed significant levels of oncogenic micro-RNAs. Additionally, we identified 1052 differentially expressed genes, and enrichment analysis further unveiled the significant upregulation of gene clusters associated with p53, NF-κB, MAPK, mTOR, and interleukin signal transduction pathways, consistent with their neoplastic cell origin. The distinctive transcriptional profile of CLL cell-derived exosomes led us to explore their effects on normal cell populations. We labeled ultra-centrifuged CLL cell-derived exosomes with fluorescent markers and incubated them with various cell types in culture conditions conducive to their physiological activity. Using confocal microscopy and flow cytometry, we observed significant uptake of CLL cell-derived exosomes by normal monocytes, fibrocytes, B cells, T cells, and CLL cells. Furthermore, incubation with CLL exosomes resulted in notable alterations in normal CD14 + monocyte polarity and subset-specific shifts in the expression of inflammatory cytokines. Remarkably, CLL cell-derived exosomes induced overexpression of the T-cell makers CD5 and CD8 in normal CD19 + cells, suggesting that CLL exosomes may promote immune-evasive reprogramming of normal B cells. Moreover, when normal T cells were incubated with CLL cell-derived exosomes, CyTOF analysis using 46 markers revealed elevated levels of immune checkpoints, including PD1, CTLA4, and LAG3, in both CD4 + and CD8 + subsets, indicating that exosomes derived from CLL cells induce T-cell dysfunction. Given their profound effect on immune cells, we wondered whether CLL exosomes affect hematopoietic cells. We previously found that normal monocyte derived fibrocytes stimulate hematopoietic colony proliferation. In sharp contrast to control fibrocytes, fibrocytes preincubated with CLL exosomes and CLL cell-derived exosomes inhibited normal BFU-E and CFU-GM colony formation, suggesting that CLL exosomes might contribute to CLL patients' anemia or neutropenia. Wondering whether CLL cell-derived exosomes affect the viability of other cell types, we found that they induced a dose-dependent apoptosis of CD19 + B cells, CLL cells but not normal T cells. In summary, CLL cell-derived exosomes exert a profound effect on gene and cell surface protein expression in immune and tissue-remodeling cells, leading to functional modifications, alteration of inflammatory cytokine levels, and suppression of normal hematopoiesis. The impact of CLL exosomes may vary across different cell types; however, as the leukemic cell mass increases, exosome levels escalate, invariably affecting CLL cell environment. The identification of exosomes with distinct molecular signatures holds promising potential for novel therapeutic interventions in future treatment of CLL.

Novel ligustilide derivatives target quorum sensing system LasR/LasB and relieve inflammatory response against Pseudomonas aeruginosa infection

The increasing antibiotic resistance driven by Pseudomonas aeruginosa typically leads to uncontrolled and persistent inflammatory damage, which is primarily attributed to the virulence and biofilms produced by the bacteria. Herein, we present a novel anti-infective drug strategy designed to inhibit the bacterial quorum sensing system, thereby attenuating P. aeruginosa virulence, and modulating inflammation from drug-resistant bacterial infections. We discovered new quorum sensing LasR/LasB inhibitors derived from the structural modification of a ligustilide derivative library. Of these compounds, 5f demonstrated significant inhibitory activity against LasB (LasB-gfp, IC50 = 8.7 μM) and a moderate inhibitory effect on P. aeruginosa biofilms (IC50 = 7.4 μM). Through live image analysis in a fluorescent protein–labeled zebrafish larva model, we observed that compound 5f significantly inhibited the migration of macrophages. Moreover, compound 5f effectively attenuated quorum sensing–mediated virulence factors and biofilm formation by P. aeruginosa. It also alleviated the inflammatory response by P. aeruginosa–infected macrophages through the downregulation of mitogen-activated protein kinase and NF-κB signal-transduction pathways. Notably, in vivo experiments, this compound demonstrated marked therapeutic effects in acute lung injury models induced by lipopolysaccharides from P. aeruginosa. These results indicate that compound 5f has the potential to be a novel anti-infective candidate against drug-resistant infections caused by P. aeruginosa.

Impact of interstitial flow on cartilage matrix synthesis and NF-kB transcription factor mRNA expression in a novel perfusion bioreactor.

This work is focused on designing an easy-to-use novel perfusion system for articular cartilage (AC) tissue engineering and using it to elucidate the mechanism by which interstitial shear upregulates matrix synthesis by articular chondrocytes (AChs). Porous chitosan-agarose (CHAG) scaffolds were synthesized and compared to bulk agarose (AG) scaffolds. Both scaffolds were seeded with osteoarthritic human AChs and cultured in a novel perfusion system with a medium flow velocity of 0.33 mm/s corresponding to 0.4 mPa surfice shear and 40 mPa CHAG interstitial shear. While there were no statistical differences in cell viability for perfusion versus static cultures for either scaffold type, CHAG scaffolds exhibited a 3.3-fold higher (p < 0.005) cell viability compared to AG scaffold cultures. Effects of combined superficial and interstitial perfusion for CHAG showed 150- and 45-fold (p < 0.0001) increases in total collagen (COL) and 13- and 2.2-fold (p < 0.001) increases in glycosaminoglycans (GAGs) over AG non-perfusion and perfusion cultures, respectively, and a 1.5-fold and 3.6-fold (p < 0.005) increase over non-perfusion CHAG cultures. Contrasting CHAG perfusion and static cultures, chondrogenic gene comparisons showed a 3.5-fold increase in collagen type II/type I (COL2A1/COL1A1) mRNA ratio (p < 0.05), and a 1.3-fold increase in aggrecan mRNA. Observed effects are linked to NF-κB signal transduction pathway inhibition as confirmed by a 3.2-fold (p < 0.05) reduction of NF-κB mRNA expression upon exposure to perfusion. Our results demonstrate that pores play a critical role in improving cell viability and that interstitial flow caused by medium perfusion through the porous scaffolds enhances the expression of chondrogenic genes and extracellular matrix through downregulating NF-κB1.

Fish Collagen Peptides Enhance Thymopoietic Gene Expression, Cell Proliferation, Thymocyte Adherence, and Cytoprotection in Thymic Epithelial Cells via Activation of the Nuclear Factor-κB Pathway, Leading to Thymus Regeneration after Cyclophosphamide-Induced Injury.

Prolonged thymic involution results in decreased thymopoiesis and thymic output, leading to peripheral T-cell deficiency. Since the thymic-dependent pathway is the only means of generating fully mature T cells, the identification of strategies to enhance thymic regeneration is crucial in developing therapeutic interventions to revert immune suppression in immunocompromised patients. The present study clearly shows that fish collagen peptides (FCPs) stimulate activities of thymic epithelial cells (TECs), including cell proliferation, thymocyte adhesion, and the gene expression of thymopoietic factors such as FGF-7, IGF-1, BMP-4, VEGF-A, IL-7, IL-21, RANKL, LTβ, IL-22R, RANK, LTβR, SDF-1, CCL21, CCL25, CXCL5, Dll1, Dll4, Wnt4, CD40, CD80, CD86, ICAM-1, VCAM-1, FoxN1, leptin, cathepsin L, CK5, and CK8 through the NF-κB signal transduction pathway. Furthermore, our study also revealed the cytoprotective effects of FCPs on TECs against cyclophosphamide-induced cellular injury through the NF-κB signaling pathway. Importantly, FCPs exhibited a significant capability to facilitate thymic regeneration in mice after cyclophosphamide-induced damage via the NF-κB pathway. Taken together, this study sheds light on the role of FCPs in TEC function, thymopoiesis, and thymic regeneration, providing greater insight into the development of novel therapeutic strategies for effective thymus repopulation for numerous clinical conditions in which immune reconstitution is required.

Crystal structure of Leptospira LSS_01692 reveals a dimeric structure and induces inflammatory responses through Toll-like receptor 2-dependent NF-κB and MAPK signal transduction pathways.

Leptospirosis is a commonly overlooked zoonotic disease that occurs in tropical and subtropical regions. Recent studies have divided the Leptospira spp. into three groups based on virulence, including pathogenic, intermediate, and saprophytic species. Pathogenic species express a protein family with leucine-rich repeat (LRR) domains, which are less expressed or absent in nonpathogenic species, highlighting the importance of this protein family in leptospirosis. However, the role of LRR domain proteins in the pathogenesis of leptospirosis is still unknown and requires further investigation. In this study, the 3D structure of LSS_01692 (rLRR38) was obtained using X-ray crystallography at a resolution of 3.2 Å. The results showed that rLRR38 forms a typical horseshoe structure with 11 α-helices and 11 β-sheets and an antiparallel dimeric structure. The interactions of rLRR38 with extracellular matrix and cell surface receptors were evaluated using ELISA and single-molecule atomic force microscopy. The results showed that rLRR38 interacted with fibronectin, collagen IV, and Toll-like receptor 2 (TLR2). Incubating HK2 cells with rLRR38 induced two downstream inflammation responses (IL-6 and MCP-1) in the TLR2 signal transduction pathway. The TLR2-TLR1 complex showed the most significant upregulation effects under rLRR38 treatment. Inhibitors also significantly inhibited nuclear factor κB and mitogen-activated protein kinases signals transduction under rLRR38 stimulation. In conclusion, rLRR38 was determined to be a novel LRR domain protein in 3D structure and demonstrated as a TLR2-binding protein that induces inflammatory responses. These structural and functional studies provide a deeper understanding of the pathogenesis of leptospirosis.

Current progress on innate immune evasion mediated by Npro protein of pestiviruses.

Interferon (IFN), the most effective antiviral cytokine, is involved in innate and adaptive immune responses and is essential to the host defense against virus invasion. Once the host was infected by pathogens, the pathogen-associated molecular patterns (PAMPs) were recognized by the host pattern recognition receptors (PRRs), which activates interferon regulatory transcription factors (IRFs) and nuclear factor-kappa B (NF-κB) signal transduction pathway to induce IFN expression. Pathogens have acquired many strategies to escape the IFN-mediated antiviral immune response. Pestiviruses cause massive economic losses in the livestock industry worldwide every year. The immune escape strategies acquired by pestiviruses during evolution are among the major difficulties in its control. Previous experiments indicated that Erns, as an envelope glycoprotein unique to pestiviruses with RNase activity, could cleave viral ss- and dsRNAs, therefore inhibiting the host IFN production induced by viral ss- and dsRNAs. In contrast, Npro, the other envelope glycoprotein unique to pestiviruses, mainly stimulates the degradation of transcription factor IRF-3 to confront the IFN response. This review mainly summarized the current progress on mechanisms mediated by Npro of pestiviruses to antagonize IFN production.

Characterization of BV6-Induced Sensitization to the NK Cell Killing of Pediatric Rhabdomyosarcoma Spheroids.

Although the overall survival in pediatric rhabdomyosarcoma (RMS) has increased over the last decades, the most aggressive subtype of alveolar RMS is in dire need of novel treatment strategies. RMS cells evade cell death induction and immune control by increasing the expression of inhibitors of apoptosis proteins (IAPs), which can be exploited and targeted with stimulation with Smac mimetics. Here, we used the Smac mimetic BV6 to re-sensitize RMS spheroids to cell death, which increased killing induced by natural killer (NK) cells. Single BV6 treatment of RMS spheroids did not reduce spheroidal growth. However, we observed significant spheroidal decomposition upon BV6 pre-treatment combined with NK cell co-cultivation. Molecularly, IAPs s are rapidly degraded by BV6, which activates NF-κB signal transduction pathways in RMS spheroids. RNA sequencing analysis validated NF-κB activation and identified a plethora of BV6-regulated genes. Additionally, BV6 released caspases from IAP-mediated inhibition. Here, caspase-8 might play a major role, as knockdown experiments resulted in decreased NK cell-mediated attack. Taken together, we improved the understanding of the BV6 mechanism of RMS spheroid sensitization to cytotoxic immune cells, which could be suitable for the development of novel combinatory cellular immunotherapy with Smac mimetics.

Computational analysis of 4-1BB-induced NFκB signaling suggests improvements to CAR cell design

BackgroundChimeric antigen receptor (CAR)-expressing cells are a powerful modality of adoptive cell therapy against cancer. The potency of signaling events initiated upon antigen binding depends on the costimulatory domain within the structure of the CAR. One such costimulatory domain is 4-1BB, which affects cellular response via the NFκB pathway. However, the quantitative aspects of 4-1BB-induced NFκB signaling are not fully understood.MethodsWe developed an ordinary differential equation-based mathematical model representing canonical NFκB signaling activated by CD19scFv-4-1BB. After a global sensitivity analysis on model parameters, we ran Monte Carlo simulations of cell population-wide variability in NFκB signaling and quantified the mutual information between the extracellular signal and different levels of the NFκB signal transduction pathway.ResultsIn response to a wide range of antigen concentrations, the magnitude of the transient peak in NFκB nuclear concentration varies significantly, while the timing of this peak is relatively consistent. Global sensitivity analysis showed that the model is robust to variations in parameters, and thus, its quantitative predictions would remain applicable to a broad range of parameter values. The model predicts that overexpressing NEMO and disabling IKKβ deactivation can increase the mutual information between antigen levels and NFκB activation.ConclusionsOur modeling predictions provide actionable insights to guide CAR development. Particularly, we propose specific manipulations to the NFκB signal transduction pathway that can fine-tune the response of CD19scFv-4-1BB cells to the antigen concentrations they are likely to encounter.3kX61-hrxkM_LLAPo69ACnVideo

TAK-242 Ameliorates Hepatic Fibrosis by Regulating the Liver-Gut Axis.

Objective The aims of this study were to investigate the impact of TAK-242 on the Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)/nuclear transcription factor-κB (NF-κB) signal transduction pathway in rats with hepatic fibrosis (HF) using the liver gut axis and to investigate the molecular mechanism of its intervention on HF. Methods SPF grade SD male rats were randomly allocated to the control, model, and TAK-242 groups. For 8 weeks, the model and TAK-242 groups received 3 mL·kg−1 (the initial dose 5 mL·kg−1) intraperitoneal injections of 40% CCL4 olive oil solution. TAK-242 (5 mg·kg−1) was administered once a day for 5 days after modeling. The pathological alterations of liver and small intestine tissues in each group were observed using H&E and Masson staining. ELISA was used to measure serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), direct bilirubin (DBIL), total bilirubin (TBIL), interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α). RT-qPCR was utilized to identify the mRNA expression level of IL-1β, IL-6, TNF-α, TLR4, MyD88, and NF-κB in rat liver and small intestine tissues. The protein level of IL-1β, IL-6, TNF-α, TLR4, MyD88, and NF-κB protein in rat liver and small intestine tissues was determined utilizing Western blot and IHC. Results TAK-242 significantly reduced AST, ALT, TBIL, and DBIL expression in HF rats' serum (P < 0.01) and alleviated liver tissue injury. Hematoxylin-eosin (H&E) and Masson staining revealed inflammatory cell infiltration and fibrous proliferation in the liver and small intestine tissue in the model group and partial cell swelling in the TAK-242 group, which indicated a considerable improvement compared to the model group. RT-qPCR, Western blot, and IHC data indicated that TAK-242 reduced the IL-1β, IL-6, TNF-α, TLR4, MyD88, and NF-κB expression in the liver and small intestine tissues of HF rats. Conclusion TAK-242 might downregulate the TLR4/MyD88/NF-κB signal pathway through the liver-gut axis, suppress the inflammatory response, and eventually alleviate HF in rats.

A photo-thermal nanocomposite capable of relieving inflammatory response to compete multidrug-resistant pseudomonas aeruginosa infection

Lung infection associated with drug-resistant P. aeruginosa and their wide spread have become a serious problem to public health. Effective antibacterial strategy without antibiotics must be developed for treatment of these infections. To combat pneumonia infected by multidrug-resistant P. aeruginosa (MRPA), a novel antibacterial nanocomoposite of AuNRs@PBArPEGMA was prepared. AuNRs@PBArPEGMA could bind with P. aeruginosa through the interaction betweeen PBArPEGMA and bacteria proved by alizarin red assay. The nanocomposite could relieve inflammtory response in MRPA-infected macrophages by downregulating MAPK and NFκB signal-transduction pathways. AuNRs@PBArPEGMA showed well photo-thermal conversion capacity leading to the temperature increasing from 20 to 80 °C under near-infrared (NIR) irradiation for 5 min. The photo-thermal capacity endowed the nanocomposites efficient antibacterial activity against MRPA. Simultaneously, AuNRs@PBArPEGMA with NIR irradiation could kill biofilm bacteria while traditional antibiotics were non-effetive. AuNRs@PBArPEGMA with NIR irradiation could treat MRPA-related lung infection. The nanocomposite with NIR reduced the inflammatory cytokines of TNF-α, IL-1β, and IL-6 by downregulating the MAPK signal pathway in bronchoalveolar lavage fluids. The number of P. aeruginosa and expression of NF-κB p65 in lung also decreased. Above all, our study provides a non-antibiotic therapeutic strategy in clinical application and demonstrated that AuNRs@PBArPEGMA with NIR irradiation showed a potential treatment for drug-resistant P. aeruginosa infection in Lung.

Cangma Huadu granules, a new drug with great potential to treat coronavirus and influenza infections, exert its efficacy through anti-inflammatory and immune regulation

Ethnopharmacological relevanceCoronavirus and influenza virus infection seriously threaten human health. Cangma Huadu Granules (CMHD) is an in-hospital preparation composed of eight traditional Chinese medicines (TCM), which has been clinically used against COVID-19 in China and may be a promising candidate for the treatment of influenza. However, the role of its treatment urgently needs to be studied.Aim of the study: To evaluate the therapeutic effects of CMHD on pneumonia induced by coronavirus (HCoV-229E) and influenza A virus (H1N1/FM1) in mice and explore its mechanism of anti-infection. Materials and methodsMice were infected with HCoV-229E or H1N1/FM1 virus through the nasal cavity. CMHD (12.1, 6.05 and 3.03 g/kg/d) or the positive control drugs were administered intragastrically. The lung index and histopathological changes were used to evaluate the therapeutic effect of CMHD. The expression of TNF-α, IL-1β, IL-6 and IL-4 in Serum and the proportion of CD4+ and CD8+ T lymphocytes in peripheral blood were detected to evaluate the anti-inflammatory and immune regulation effects of CMHD, respectively. Furthermore, the levels of p–NF–κBp65/ NF-κB p65, which was the key targets of the NF-κB pathway was analyzed. ResultsIn HCoV-229E-induced pneumonia, the lung index was markedly reduced, and lung pathology was improved in mice that treated with CMHD (12.1, 6.05 g/kg/d). Meanwhile, the expression of TNF-α, IL-6 were obviously inhibited, but the expression of IL-4 was significantly increased in CMHD groups. Compared with the model group, CMHD could also markedly upregulate the level of CD4+ and CD8+. Furthermore, CMHD has a markedly effect on inhibit the expression of p–NF–κB p65/NF-κB p65 in the lung. In H1N1-induced pneumonia, the lung index of mice in the CMHD (12.1 g/kg/d) treatment group was lower than that in the model group, and less inflammatory infiltration could be seen in the lung pathological. Moreover, CMHD could also obviously decrease the expression of TNF-α, IL-1β, IL-6, but significantly increase the expression of IL-4. Except for that, CMHD could also markedly downregulate the level of CD4+ and upregulate the level of CD8+ compared with the model group. In addition, CMHD has a markedly effect on inhibit the expression of p–NF–κB p65/NF-κB p65 in the lung. ConclusionCMHD can significantly combats viral infections caused by HCoV-229E and H1N1, and the mechanism may be related to its multiple functions of anti-inflammatory, immunity regulating and inhibiting NF-κB signal transduction pathway.

Crosstalk between E-Cadherin/β-Catenin and NF-κB Signaling Pathways: The Regulation of Host-Pathogen Interaction during Leptospirosis.

Approximately 1 million cases of leptospirosis, an emerging infectious zoonotic disease, are reported each year. Pathogenic Leptospira species express leucine-rich repeat (LRR) proteins that are rarely expressed in non-pathogenic Leptospira species. The LRR domain-containing protein family is vital for the virulence of pathogenic Leptospira species. In this study, the biological mechanisms of an essential LRR domain protein from pathogenic Leptospira were examined. The effects of Leptospira and recombinant LRR20 (rLRR20) on the expression levels of factors involved in signal transduction were examined using microarray, quantitative real-time polymerase chain reaction, and western blotting. The secreted biomarkers were measured using an enzyme-linked immunosorbent assay. rLRR20 colocalized with E-cadherin on the cell surface and activated the downstream transcription factor β-catenin, which subsequently promoted the expression of MMP7, a kidney injury biomarker. Additionally, MMP7 inhibitors were used to demonstrate that the secreted MMP7 degrades surface E-cadherin. This feedback inhibition mechanism downregulated surface E-cadherin expression and inhibited the colonization of Leptospira. The degradation of surface E-cadherin activated the NF-κB signal transduction pathway. Leptospirosis-associated acute kidney injury is associated with the secretion of NGAL, a downstream upregulated biomarker of the NF-κB signal transduction pathway. A working model was proposed to illustrate the crosstalk between E-cadherin/β-catenin and NF-κB signal transduction pathways during Leptospira infection. Thus, rLRR20 of Leptospira induces kidney injury in host cells and inhibits the adhesion and invasion of Leptospira through the upregulation of MMP7 and NGAL.

Discovery of Phenolic Glycoside from Hyssopus cuspidatus Attenuates LPS-Induced Inflammatory Responses by Inhibition of iNOS and COX-2 Expression through Suppression of NF-κB Activation.

It seems quite necessary to obtain effective substances from natural products against inflammatory response (IR) as there are presently clinical problems regarding accompanying side effects and lowered quality of life. This work aimed to investigate the abilities of hyssopuside (HY), a novel phenolic glycoside isolated from Hyssopus cuspidatus (H. cuspidatus), against IR in lipopolysaccharide (LPS)-induced RAW 264.7 cells and mouse peritoneal macrophages. The results indicated that HY could reduce nitric oxide (NO) production and inhibit the production and secretion of pro-inflammatory mediators including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) in LPS-stimulated macrophages. Moreover, data from the immunofluorescence study showed that HY suppressed nuclear translocation of nuclear factor-kappa B (NF-κB) upon LPS induction. The Western blot results suggested that HY reversed the LPS-induced degradation of IκB (inhibitor of NF-κB), which is normally required for the activation of NF-κB. Meanwhile, the overexpression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) diminished significantly with the presence of HY in response to LPS stimulation. On the other hand, HY had a negligible impact on the activation of mitogen-activated protein kinase (MAPK) pathways. Moreover, an in silico study of HY against four essential proteins/enzymes revealed that COX-2 was the most efficient enzyme for the interaction, and binding of residues Phe179, Asn351, and Ser424 with HY played crucial roles in the observed activity. The structure analysis indicated the typical characterizations with phenylethanoid glycoside contributed to the anti-inflammatory effects of HY. These results indicated that HY manipulated its anti-inflammatory effects mainly through blocking the NF-κB signal transduction pathways. Collectively, we believe that HY could be a potential alternative phenolic agent for alleviating excessive inflammation in many inflammation-associated diseases.

Anti-inflammatory effect of Kaba Sura Kudineer (AYUSH approved COVID-19 drug)-A Siddha poly-herbal formulation against lipopolysaccharide induced inflammatory response in RAW-264.7 macrophages cells

Ethnopharmacological relevanceMedicinal importance and potential activity of Siddha herbal formulations have proved over several centuries against a wide range of causative agents as Influenza, Dengue, Chikungunya, and Tuberculosis. The traditional medicine system of Siddha is a valuable therapeutic approach for treating viral respiratory infections like Coronavirus disease 2019 (COVID-19) and can be effectively employed to target the host response and preventive care to boost the immune system. Kaba Sura Kudineer (KSK), an official polyherbal formulation has been used in Siddha traditional medicine for centuries. However, the role of KSK in regulating inflammation and the underlying molecular mechanisms has remained elusive. Aim of the studyThe goal of this study was to evaluate the anti-inflammatory effect of KSK using lipopolysaccharide (LPS) stimulated RAW 264.7 murine macrophage cells. Materials and methodsRaw 264.7 murine macrophage cells were used for this study. The Inflammatory mediators and cytokines were measured by enzyme-linked immunosorbent assay (ELISA). The NF-κB nulcear translocation and protein expression of iNOS, COX-2 was analyzed with westernblot. ResultsKSK supplementation decreased LPS mediated TLR-4 production and secretion of pro-inflammatory mediators and cytokines including IL-6, TNF-α, COX-2 and PGE-2. Moreover, it inhibited the production of nitric oxide (NO) and thereby inhibited the expression of iNOS in the cell. The Western blot analysis further confirmed that KSK strongly prevented the LPS-induced degradation of IκB which is normally required for the activation of NF-κB and hereby suppressed nuclear translocation of NF-κB. The protein expression of iNOS, COX-2 was significantly decreased with the presence of KSK treatment. Results suggested that KSK manipulates its anti-inflammatory effects mainly through blocking the TLR mediated NF-κB signal transduction pathways. ConclusionsTogether, this study has proven that KSK could be a potential therapeutic drug for alleviating excessive inflammation in many inflammation-associated diseases like COVID-19.

Anticancer Effects of I-BET151, an Inhibitor of Bromodomain and Extra-Terminal Domain Proteins.

I-BET151 is an inhibitor of bromodomain and extra-terminal domain (BET) proteins that selectively inhibits BET family members (BRD2, BRD3, BRD4, and BRDT). Over the past ten years, many studies have demonstrated the potential of I-BET151 in cancer treatment. Specifically, I-BET151 causes cell cycle arrest and inhibits tumor cell proliferation in some hematological malignancies and solid tumors, such as breast cancer, glioma, melanoma, neuroblastoma, and ovarian cancer. The anticancer activity of I-BET151 is related to its effects on NF-κB, Notch, and Hedgehog signal transduction pathway, tumor microenvironment (TME) and telomere elongation. Remarkably, the combination of I-BET151 with select anticancer drugs can partially alleviate the occurrence of drug resistance in chemotherapy. Especially, the combination of forskolin, ISX9, CHIR99021, I-BET151 and DAPT allows GBM cells to be reprogrammed into neurons, and this process does not experience an intermediate pluripotent state. The research on the anticancer mechanism of I-BET151 will lead to new treatment strategies for clinical cancer.

The Potential Role of FREM1 and Its Isoform TILRR in HIV-1 Acquisition through Mediating Inflammation.

FREM1 (Fras-related extracellular matrix 1) and its splice variant TILRR (Toll-like interleukin-1 receptor regulator) have been identified as integral components of innate immune systems. The potential involvement of FREM1 in HIV-1 (human immunodeficiency virus 1) acquisition was suggested by a genome-wide SNP (single nucleotide polymorphism) analysis of HIV-1 resistant and susceptible sex workers enrolled in the Pumwani sex worker cohort (PSWC) in Nairobi, Kenya. The studies showed that the minor allele of a FREM1 SNP rs1552896 is highly enriched in the HIV-1 resistant female sex workers. Subsequent studies showed that FREM1 mRNA is highly expressed in tissues relevant to mucosal HIV-1 infection, including cervical epithelial tissues, and TILRR is a major modulator of many genes in the NF-κB signal transduction pathway. In this article, we review the role of FREM1 and TILRR in modulating inflammatory responses and inflammation, and how their influence on inflammatory responses of cervicovaginal tissue could enhance the risk of vaginal HIV-1 acquisition.

Effects of Enalapril on TLR2/NF-κB Signaling Pathway and Inflammatory Factors in Rabbits with Chronic Heart Failure.

Chronic heart failure (CHF) refers to the state of persistent heart failure, which is a complex clinical syndrome of various advanced heart diseases. The toll-like receptor 2 (TLR2)/nuclear transcription factor-κB (NF-κB) signal transduction pathway is one of the pathological mechanisms of CHF. Adriamycin can significantly induce the upregulation of TLR2 expression. Angiotensin-converting enzyme inhibitors (ACEI) are commonly used drugs for the treatment of CHF. In our study, the CHF model was established by injection of doxorubicin into the rabbit ear vein. The effect of enalapril on the TLR2/NF-κB signaling pathway in CHF rabbits has been analyzed and determined. Our research results showed that enalapril reduced the inflammatory response by inhibiting the activation of the TLR2/NF-κB signaling pathway, thereby improving cardiac structure, myocardial remodeling, and cardiac function.

TRAF3 and NBR1 both influence the effect of the disease-causing CYLD(Arg936X) mutation on NF-κB activity.

Recently described Hungarian and Anglo-Saxon pedigrees that are affected by CYLD cutaneous syndrome (syn: Brooke-Spiegler syndrome (BSS)) carry the same disease-causing mutation (c.2806C>T, p.Arg936X) of the cylindromatosis (CYLD) gene but exhibit striking phenotypic differences. Using whole exome sequencing, missense genetic variants of the TRAF3 and NBR1 genes were identified in the affected family members of the Hungarian pedigree that are not present in the Anglo-Saxon pedigree. This suggested that the affected proteins (TRAF3 and NBR1) are putative phenotype-modifying factors. An in vitro experimental system was set up to clarify how wild type and mutant TRAF3 and NBR1 modify the effect of CYLD on the NF-κB signal transduction pathway. Our study revealed that the combined expression of mutant CYLD(Arg936X) with TRAF3 and NBR1 caused increased NF-κB activity, regardless of the presence or absence of mutations in TRAF3 and NBR1. We concluded that increased expression levels of these proteins further strengthen the effect of the CYLD(Arg936X) mutation on NF-κB activity in HEK293 cells and may explain the phenotype-modifying effect of these genes in CYLD cutaneous syndrome. These results raise the potential that detecting the levels of TRAF3 and NBR1 might help explaining phenotypic differences and prognosis of CCS.