TAK1-TABs Complex: A Central Signalosome in Inflammatory Responses

Associations of TRAF2 (rs867186), TAB2 (rs237025), IKBKB (rs13278372) Polymorphisms and TRAF2, TAB2, IKBKB Protein Levels with Clinical and Morphological Features of Pituitary Adenomas

AIM

The aim of this study was to determine associations of TRAF2 (rs867186), TAB2 (rs237025), IKBKB (rs13278372) gene polymorphisms and TRAF2, TAB2, IKBKB protein levels with clinical and morphological features of pituitary adenomas (PAs).

METHODS

This case-control study included 459 individuals divided into two groups: a control group (n = 320) and a group of individuals with PAs (n = 139). DNA from peripheral blood leukocytes was isolated using salt precipitation and column method. Real-time PCR was used for TRAF2 (rs867186), TAB2 (rs237025), and IKBKB (rs13278372) SNP genotyping, and TRAF2, TAB2, IKBKB protein concentration measurements were performed by immunoenzymatic analysis tests using a commercial ELISA kit according to the manufacturer's recommendations. The labeling index Ki-67 was determined by immunohistochemical analysis using a monoclonal antibody (clone SP6; Spring Bioscience Corporation). Statistical data analysis was performed using the programs "IMB SPSS Statistics 29.0".

RESULTS

We found significant differences in TRAF2 (rs867186) genotypes (AA, AG, GG) between groups: 79.1%, 17.3%, 3.6% vs. 55.3%, 20.9%, 23.8% (p < 0.001). The G allele was less frequent in the PA group than in controls (12.2% vs. 34.2%, p < 0.001). The AG and GG genotypes reduced PA occurrence by 1.74-fold and 9.43-fold, respectively, compared to AA (p < 0.001). In the dominant model, GG and AG genotypes reduced PA odds by 3.07-fold, while in the recessive model, the GG genotype reduced PA odds by 8.33-fold (p < 0.001). Each G allele decreased PA odds by 2.49-fold in the additive model (p < 0.001). Microadenomas had significant genotype differences compared to controls: 81.3%, 18.8%, 0.0% vs. 55.3%, 20.9%, 23.8% (p < 0.001), with the G allele being less frequent (9.4% vs. 34.2%, p < 0.001). In macroadenomas, genotype differences were 78%, 16.5%, 5.5% vs. 55.3%, 20.9%, 23.8% (p < 0.001), and the G allele was less common (13.7% vs. 34.2%, p < 0.001). The dominant model showed that GG and AG genotypes reduced microadenoma odds by 3.5-fold (p = 0.001), and each G allele reduced microadenoma odds by 3.1-fold (p < 0.001). For macroadenomas, the GG genotype reduced odds by 6.1-fold in the codominant model (p < 0.001) and by 2.9-fold in GG and AG genotypes combined compared to AA (p < 0.001). The recessive model indicated the GG genotype reduced macroadenoma odds by 5.3-fold (p < 0.001), and each G allele reduced odds by 2.2-fold in the additive model (p < 0.001).

CONCLUSIONS

The TRAF2 (rs867186) G allele and GG genotype are significantly associated with reduced odds of pituitary adenomas, including both microadenomas and macroadenomas, compared to the AA genotype. These findings suggest a protective role of the G allele against the occurrence of these tumors.

Toll-like receptors and integrins crosstalk

Immune system recognizes invading microbes at both pathogen and antigen levels. Toll-like receptors (TLRs) play a key role in the first-line defense against pathogens. Major functions of TLRs include cytokine and chemokine production. TLRs share common downstream signaling pathways with other receptors. The crosstalk revolving around TLRs is rather significant and complex, underscoring the intricate nature of immune system. The profiles of produced cytokines and chemokines via TLRs can be affected by other receptors. Integrins are critical heterodimeric adhesion molecules expressed on many different cells. There are studies describing synergetic or inhibitory interplay between TLRs and integrins. Thus, we reviewed the crosstalk between TLRs and integrins. Understanding the nature of the crosstalk could allow us to modulate TLR functions via integrins.

A polysaccharide PRCP from Rosa cymosa Tratt fruit: Structural characteristics and immunomodulatory effects via MAPK pathway modulation in vitro

The Rosa cymosa Tratt, an herbal plant from the Rosaceae family, has historically been valued in China for its medicinal and edible properties. In this study, a novel polysaccharide from R. cymosa fruit, termed PRCP (purified R. cymosa polysaccharide), was isolated using water extraction, decolorization, deproteinization, and ion-exchange chromatography. The structural characteristics of PRCP were investigated using monosaccharide composition analysis, methylation, GPC, FTIR, CD, and NMR spectroscopy. The immunomodulatory effect and potential mechanism of PRCP were evaluated in vitro using a macrophage cell model. Results indicated that PRCP (37.28 kDa) is a highly branched polysaccharide (72.61 %) primarily composed of arabinogalactan, rhamnogalacturonan, and galactoglucan domains with 13 types of glycosidic linkage fragments. Furthermore, PRCP appears to modulate immunomodulatory effects by influencing the phosphorylation of P38 and JNK proteins in the MAPK pathway. Collectively, these findings highlight the potential of PRCP as a promising natural functional food ingredient for immunostimulation.

PDTC improves cognitive impairment in LPS-induced ARDS by regulating miR-181c/NF-κB axis-mediated neuroinflammation

BACKGROUND

Cognitive impairment is a severe complication of acute respiratory distress syndrome (ARDS). Emerging studies have revealed the effects of pyrrolidine dithiocarbamate (PDTC) on improving surgery-induced cognitive impairment. The major aim of the study was to investigate whether PDTC protected against ARDS-induced cognitive dysfunction and to identify the underlying mechanisms involved.

METHODS

The rat model of ARDS was established by intratracheal instillation of lipopolysaccharide (LPS), followed by treatment with PDTC. The cognitive function of rats was analyzed by the Morris Water Maze, and pro-inflammatory cytokines were assessed by quantitative real-time PCR, enzyme-linked immunosorbent assay, and western blot assays. A dual-luciferase reporter gene assay was performed to identify the relationship between miR-181c and its target gene, TAK1 binding protein 2 (TAB2).

RESULTS

The results showed that PDTC improved cognitive impairment and alleviated neuroinflammation in the hippocampus in LPS-induced ARDS model. Furthermore, we demonstrated that miR-181c expression was downregulated in the hippocampus of the ARDS rats, which was restored by PDTC treatment. In vitro studies showed that miR-181c alleviated LPS-induced pro-inflammatory response by inhibiting TAB2, a critical molecule in the nuclear factor (NF)-κB signaling pathway.

CONCLUSION

PDTC improves cognitive impairment in LPS-induced ARDS by regulating miR-181c/NF-κB axis-mediated neuroinflammation, providing a potential opportunity for the treatment of this disease.

Mycobacterium tuberculosis Rv1043c regulates the inflammatory response by inhibiting the phosphorylation of TAK1

Mycobacterium tuberculosis can manipulate the host immunity through its effectors to ensure intracellular survival and colonization. Rv1043c has been identified as an effector potentially involved in M. tuberculosis pathogenicity. To explore the function of M. tuberculosis Rv1043c during infection, we overexpressed this protein in M. smegmatis, a non-pathogenic surrogate model in tuberculosis research. Here, we reported that Rv1043c enhanced mycobacterial survival and down-regulated the release of pro-inflammatory cytokines in macrophages and mice. In addition, Rv1043c inhibited the activation of MAPK and NF-κB signaling by preventing the phosphorylation of TAK1 indirectly. In conclusion, these data suggest that Rv1043c regulates the immune response and enhances the survival of recombinant M. smegmatis in vitro and in vivo.

Thrombospondin-1 Regulates Trophoblast Necroptosis via NEDD4-Mediated Ubiquitination of TAK1 in Preeclampsia

Preeclampsia (PE) is considered as a disease of placental origin. However, the specific mechanism of placental abnormalities remains elusive. This study identified thrombospondin-1 (THBS1) is downregulated in preeclamptic placentae and negatively correlated with blood pressure. Functional studies show that THBS1 knockdown inhibits proliferation, migration, and invasion and increases the cycle arrest and apoptosis rate of HTR8/SVneo cells. Importantly, THBS1 silencing induces necroptosis in HTR8/SVneo cells, accompanied by the release of damage-associated molecular patterns (DAMPs). Necroptosis inhibitors necrostatin-1 and GSK'872 restore the trophoblast survival while pan-caspase inhibitor Z-VAD-FMK has no effect. Mechanistically, the results show that THBS1 interacts with transforming growth factor B-activated kinase 1 (TAK1), which is a central modulator of necroptosis quiescence and affects its stability. Moreover, THBS1 silencing up-regulates the expression of neuronal precursor cell-expressed developmentally down-regulated 4 (NEDD4), which acts as an E3 ligase of TAK1 and catalyzes K48-linked ubiquitination of TAK1 in HTR8/SVneo cells. Besides, THBS1 attenuates PE phenotypes and improves the placental necroptosis in vivo. Taken together, the down-regulation of THBS1 destabilizes TAK1 by activating NEDD4-mediated, K48-linked TAK1 ubiquitination and promotes necroptosis and DAMPs release in trophoblast cells, thus participating in the pathogenesis of PE.

Endothelial dysfunction: mechanisms and contribution to diseases

The endothelium, lining the inner surface of blood vessels and spanning approximately 3 m2, serves as the largest organ in the body. Comprised of endothelial cells, the endothelium interacts with other bodily components including the bloodstream, circulating cells, and the lymphatic system. Functionally, the endothelium primarily synchronizes vascular tone (by balancing vasodilation and vasoconstriction) and prevents vascular inflammation and pathologies. Consequently, endothelial dysfunction disrupts vascular homeostasis, leading to vascular injuries and diseases such as cardiovascular, cerebral, and metabolic diseases. In this opinion/perspective piece, we explore the recently identified mechanisms of endothelial dysfunction across various disease subsets and critically evaluate the strengths and limitations of current therapeutic interventions at the pre-clinical level.

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.

Mycobacterium tuberculosis suppresses host antimicrobial peptides by dehydrogenating L-alanine

Antimicrobial peptides (AMPs), ancient scavengers of bacteria, are very poorly induced in macrophages infected by Mycobacterium tuberculosis (M. tuberculosis), but the underlying mechanism remains unknown. Here, we report that L-alanine interacts with PRSS1 and unfreezes the inhibitory effect of PRSS1 on the activation of NF-κB pathway to induce the expression of AMPs, but mycobacterial alanine dehydrogenase (Ald) Rv2780 hydrolyzes L-alanine and reduces the level of L-alanine in macrophages, thereby suppressing the expression of AMPs to facilitate survival of mycobacteria. Mechanistically, PRSS1 associates with TAK1 and disruptes the formation of TAK1/TAB1 complex to inhibit TAK1-mediated activation of NF-κB pathway, but interaction of L-alanine with PRSS1, disables PRSS1-mediated impairment on TAK1/TAB1 complex formation, thereby triggering the activation of NF-κB pathway to induce expression of AMPs. Moreover, deletion of antimicrobial peptide gene β-defensin 4 (Defb4) impairs the virulence by Rv2780 during infection in mice. Both L-alanine and the Rv2780 inhibitor, GWP-042, exhibits excellent inhibitory activity against M. tuberculosis infection in vivo. Our findings identify a previously unrecognized mechanism that M. tuberculosis uses its own alanine dehydrogenase to suppress host immunity, and provide insights relevant to the development of effective immunomodulators that target M. tuberculosis.

TAK1 in Vascular Signaling: "Friend or Foe"?

The maintenance of normal vascular function and homeostasis is largely dependent on the signaling mechanisms that occur within and between cells of the vasculature. TGF-β-activated kinase 1 (TAK1), a multifaceted signaling molecule, has been shown to play critical roles in various tissue types. Although the precise function of TAK1 in the vasculature remains largely unknown, emerging evidence suggests its potential involvement in both physiological and pathological processes. A comprehensive search strategy was employed to identify relevant studies, PubMed, Web of Science, and other relevant databases were systematically searched using keywords related to TAK1, TABs and MAP3K7.In this review, we discussed the role of TAK1 in vascular signaling, with a focus on its function, activation, and related signaling pathways. Specifically, we highlight the TA1-TABs complex is a key factor, regulating vascular smooth muscle cells (VSMCs) and endothelial cells (ECs) involved in the processes of inflammation, vascular proliferation and angiogenesis. This mini review aims to elucidate the evidence supporting TAK1 signaling in the vasculature, in order to better comprehend its beneficial and potential harmful effects upon TAK1 activation in vascular tissue.

Targeting TGFβ-activated kinase-1 activation in microglia reduces CAR T immune effector cell-associated neurotoxicity syndrome

Cancer immunotherapy with chimeric antigen receptor (CAR) T cells can cause immune effector cell-associated neurotoxicity syndrome (ICANS). However, the molecular mechanisms leading to ICANS are not well understood. Here we examined the role of microglia using mouse models and cohorts of individuals with ICANS. CD19-directed CAR (CAR19) T cell transfer in B cell lymphoma-bearing mice caused microglia activation and neurocognitive deficits. The TGFβ-activated kinase-1 (TAK1)-NF-κB-p38 MAPK pathway was activated in microglia after CAR19 T cell transfer. Pharmacological TAK1 inhibition or genetic Tak1 deletion in microglia using Cx3cr1CreER:Tak1fl/fl mice resulted in reduced microglia activation and improved neurocognitive activity. TAK1 inhibition allowed for potent CAR19-induced antilymphoma effects. Individuals with ICANS exhibited microglia activation in vivo when studied by translocator protein positron emission tomography, and imaging mass cytometry revealed a shift from resting to activated microglia. In summary, we prove a role for microglia in ICANS pathophysiology, identify the TAK1-NF-κB-p38 MAPK axis as a pathogenic signaling pathway and provide a rationale to test TAK1 inhibition in a clinical trial for ICANS prevention after CAR19 T cell-based cancer immunotherapy.

TAK1 inhibition leads to RIPK1-dependent apoptosis in immune-activated cancers

Poor survival and lack of treatment response in glioblastoma (GBM) is attributed to the persistence of glioma stem cells (GSCs). To identify novel therapeutic approaches, we performed CRISPR/Cas9 knockout screens and discovered TGFβ activated kinase (TAK1) as a selective survival factor in a significant fraction of GSCs. Loss of TAK1 kinase activity results in RIPK1-dependent apoptosis via Caspase-8/FADD complex activation, dependent on autocrine TNFα ligand production and constitutive TNFR signaling. We identify a transcriptional signature associated with immune activation and the mesenchymal GBM subtype to be a characteristic of cancer cells sensitive to TAK1 perturbation and employ this signature to accurately predict sensitivity to the TAK1 kinase inhibitor HS-276. In addition, exposure to pro-inflammatory cytokines IFNγ and TNFα can sensitize resistant GSCs to TAK1 inhibition. Our findings reveal dependency on TAK1 kinase activity as a novel vulnerability in immune-activated cancers, including mesenchymal GBMs that can be exploited therapeutically.

GM1 ganglioside protects against LPS-induced neuroinflammatory and oxidative responses by inhibiting the activation of Akt, TAK1 and NADPH oxidase in MG6 microglial cells

GM1 is a major brain ganglioside that exerts neurotrophic, neuroprotective and antineuroinflammatory effects. The aim of this study was to obtain insights into the antineuroinflammatory mechanisms of exogenous GM1 in lipopolysaccharide (LPS)-stimulated MG6 mouse transformed microglial cell line. First, we found that GM1 prevented the LPS-induced transformation of microglia into an amoeboid-like shape. GM1 treatment inhibited LPS-induced expression of inducible nitric oxide synthase, cyclooxygenase-2 (COX-2), and proinflammatory cytokines such as TNF-α, IL-1β and IL-6 in MG6 cells. In LPS-treated mice, GM1 also reduced striatal microglia activation and attenuated COX-2 expression. Subsequent mechanistic studies showed that GM1 suppressed LPS-induced nuclear translocation of nuclear factor κB (NF-κB) and activator protein-1 (AP-1), two critical transcription factors responsible for the production of proinflammatory mediators. GM1 exhibited antineuroinflammatory properties by suppressing Akt/NF-κB signaling and the activation of mitogen-activated protein kinases (MAPKs), including p38 MAPK, extracellular signal-regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase (JNK). Furthermore, GM1 suppressed LPS-induced activation of transforming growth factor-β-activated kinase 1 (TAK1) and NADPH oxidase 2 (NOX2), upstream regulators of the IκBα/NF-κB and MAPK/AP-1 signaling pathways. GM1 also inhibited NOX-mediated reactive oxygen species (ROS) production and protected against LPS-induced MG6 cell death, suggesting an antioxidant role of GM1. In conclusion, GM1 exerts both antineuroinflammatory and antioxidative effects by inhibiting Akt, TAK1 and NOX2 activation.

BAP31 Promotes Adhesion Between Endothelial Cells and Macrophages Through the NF-κB Signaling Pathway in Sepsis

Purpose

To investigate the role of B cell receptor associated protein 31 (BAP31) in the pathogenesis of sepsis.

Methods

Cecal ligation and puncture (CLP)-induced C57BL/6J mice, and LPS-challenged endothelial cells (HUVECs) were established to mimic a sepsis animal model and a sepsis cell model, respectively. Cre/LoxP and shRNA methods were used for BAP31 knockdown in vivo and in vitro respectively. Neutrophils/macrophages-endothelial cocultures were used to evaluate neutrophils or macrophages infiltration and adhesion to endothelial cells. Cox proportional hazards model was used to evaluate the survival time of mice. Western blotting (WB) and Quantitative real-time polymerase chain reaction (qRT-PCR) were used to detect toll-like receptor (TLR) signaling pathway, transforming growth factor β activated kinase 1 (TAK1) signaling pathway and phosphoinositide-3 kinases-protein kinase B (PI3K/AKT) signaling pathway.

Results

Deletion of BAP31 reduced CLP-induced mortality of mice, histological damage with less interstitial edema, and neutrophils and macrophages infiltration. IHC and IF showed that BAP31 knockdown significantly decreases the expressions of ICAM1 and VCAM1 both in vivo and in vitro. Coculture showed that LPS-induced neutrophils or macrophages adhesion to endothelial cells was significantly weakened in BAP31 knockdown cells. In addition, BAP31 knockdown of endothelial cells decreased the expression of CD80 and CD86 on the surface of macrophages as well as interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α) during sepsis. Mechanistically, LPS-induced the activation of TLR4, MyD88 and TRAF6, and the phosphorylation of TAK1, PI3K, AKT, IκBα and IKKα/β, resulting in activation of nuclear factor kappa B (NF-κB) p65 in endothelial cells. However, BAP31 knockdown significantly reversed the expressions of associated proteins.

Conclusion

BAP31 up-regulated the expressions of ICAM1 and VCAM1 in endothelial cells leading to sepsis-associated organ injury. This may be involved in activation of TLR signaling pathway, TAK1 pathway, and PI3K-AKT signaling pathway.

"Other Than NLRP3" Inflammasomes: Multiple Roles in Brain Disease

Human neuroinflammatory and neurodegenerative diseases, whose prevalence keeps rising, are still unsolved pathobiological/therapeutical problems. Among others, recent etiology hypotheses stressed as their main driver a chronic neuroinflammation, which is mediated by innate immunity-related protein oligomers: the inflammasomes. A panoply of exogenous and/or endogenous harmful agents activates inflammasomes' assembly, signaling, and IL-1β/IL-18 production and neural cells' pyroptotic death. The underlying concept is that inflammasomes' chronic activation advances neurodegeneration while their short-lasting operation restores tissue homeostasis. Hence, from a therapeutic standpoint, it is crucial to understand inflammasomes' regulatory mechanisms. About this, a deluge of recent studies focused on the NLRP3 inflammasome with suggestions that its pharmacologic block would hinder neurodegeneration. Yet hitherto no evidence proves this view. Moreover, known inflammasomes are numerous, and the mechanisms regulating their expression and function may vary with the involved animal species and strains, as well as organs and cells, and the harmful factors triggered as a result. Therefore, while presently leaving out some little-studied inflammasomes, this review focuses on the "other than NLRP3" inflammasomes that participate in neuroinflammation's complex mechanisms: NLRP1, NLRP2, NLRC4, and AIM2. Although human-specific data about them are relatively scant, we stress that only a holistic view including several human brain inflammasomes and other potential pathogenetic drivers will lead to successful therapies for neuroinflammatory and neurodegenerative diseases.

Upregulation of TRIM16 mitigates doxorubicin-induced cardiotoxicity by modulating TAK1 and YAP/Nrf2 pathways in mice

The clinic application of doxorubicin (DOX) is severely limited by its severe cardiotoxicity. Tripartite motif-containing protein 16 (TRIM16) has E3 ubiquitin ligase activity and is upregulated in cardiomyocytes under pathological stress, yet its role in DOX-induced cardiotoxicity remains elusive. This study aims to investigate the role and mechanism of TRIM16 in DOX cardiotoxicity. Following TRIM16 overexpression in hearts with AAV9-TRIM16, mice were intravenously administered DOX at a dose of 4 mg/kg/week for 4 weeks to assess the impact of TRIM16 on doxorubicin-induced cardiotoxicity. Transfection of OE-TRIM16 plasmids and siRNA-TRIM16 was performed in neonatal rat cardiomyocytes (NRCMs). Our results revealed that DOX challenge elicited a significant upregulation of TRIM16 proteins in cardiomyocytes. TRIM16 overexpression efficiently ameliorated cardiac function while suppressing inflammation, ROS generation, apoptosis and fibrosis provoked by DOX in the myocardium. TRIM16 knockdown exacerbated these alterations caused by DOX in NRCMs. Mechanistically, OE-TRIM16 augmented the ubiquitination and degradation of p-TAK1, thereby arresting JNK and p38MAPK activation evoked by DOX in cardiomyocytes. Furthermore, DOX enhanced the interaction between p-TAK1 and YAP1 proteins, resulting in a reduction in YAP and Nrf2 proteins in cardiomyocytes. OE-TRIM16 elevated YAP levels and facilitated its nuclear translocation, thereby promoting Nrf2 expression and mitigating oxidative stress and inflammation. This effect was nullified by siTRIM16 or TAK1 inhibitor Takinib. Collectively, the current study elaborates that upregulating TRIM16 mitigates DOX-induced cardiotoxicity through anti-inflammation and anti-oxidative stress by modulating TAK1-mediated p38 and JNK as well as YAP/Nrf2 pathways, and targeting TRIM16 may provide a novel strategy to treat DOX-induced cardiotoxicity.

[Bioinformatics analysis and validation of the interaction between PML protein and TAB1 protein]

OBJECTIVE

To analyze the interaction between PML protein and TAB1 protein using bioinformatic approaches and experimentally verify the results.

METHODS

Using Rosetta software, a 3D model of TAB1 protein was constructed through a comparative modeling approach; the secondary structure of PML protein was retrieved in the PDB database and its crystal structure and 3D structure were resolved. Zdock 3.0.2 software was used to perform protein-protein docking of PML and TAB1, and the best conformation was extracted for molecular structure analysis of the docking model. The interaction between the two proteins was detected using immunoprecipitation in α-MMC-treated M1 inflammatory macrophages.

RESULTS

When 6IMQ of PML was used as the docking site, PML protein formed 3 salt bridges, 6 hydrogen bonds and 6 hydrophobic interactions with TAB1 proteins; when 5YUF of PML was used as the docking site, PML protein formed 1 hydrogen bond, 3 electrostatic interactions and 9 hydrophobic interactions with TAB1 proteins, and both of the docking modes formed good molecular docking and interactions. In the M1 inflammatory macrophages treated with α-MMC for 4 h, positive protein bands of PML and TAB1 were detected in the cell lysates in PML-IP group.

CONCLUSION

PML protein can interact strongly with TAB1 protein.

Cytoplasmic Polyadenylation Element Binding Protein 1 and Atherosclerosis: Prospective Target and New Insights

The ribonucleic acid (RNA)-binding protein Cytoplasmic Polyadenylation Element Binding Protein 1 (CPEB1), a key member of the CPEB family, is essential in controlling gene expression involved in both healthy physiological and pathological processes. CPEB1 can bind to the 3'- untranslated regions (UTR) of substrate messenger ribonucleic acid (mRNA) and regulate its translation. There is increasing evidence that CPEB1 is closely related to the pathological basis of atherosclerosis. According to recent investigations, many pathological processes, including inflammation, lipid metabolism, endothelial dysfunction, angiogenesis, oxidative stress, cellular senescence, apoptosis, and insulin resistance, are regulated by CPEB1. This review considers the prevention and treatment of atherosclerotic heart disease in relation to the evolution of the physiological function of CPEB1, recent research breakthroughs, and the potential participation of CPEB1 in atherosclerosis.

The Function of ASK1 in Sepsis and Stress-Induced Disorders

Apoptosis signal-regulating kinase 1 (ASK1) is a serine-threonine kinase that is ubiquitously expressed in nucleated cells and is responsible for the activation of multiple mitogen-activated protein kinases (MAPK) to regulate cell stress. Activation of ASK1 via cellular stress leads to activation of downstream signaling components, activation of transcription factors, and proinflammatory cytokine production. ASK1 is also expressed in anucleate platelets and is a key player in platelet activation as it is important for signaling. Interestingly, the mechanism of ASK1 activation is cell type-dependent. In this review we will explore how ASK1 regulates a variety of cellular processes from innate immune function to thrombosis and hemostasis. We will discuss how ASK1 influences FcγRIIA-mediated platelet reactivity and how that reactivity drives platelet clearance. Furthermore, we will explore the role of ASK1 in thromboxane (TxA2) generation, which highlights differences in the way ASK1 functions in mouse and human platelets.

Dual-Specificity Phosphatases in Regulation of Tumor-Associated Macrophage Activity

The regulation of protein kinases by dephosphorylation is a key mechanism that defines the activity of immune cells. A balanced process of the phosphorylation/dephosphorylation of key protein kinases by dual-specificity phosphatases is required for the realization of the antitumor immune response. The family of dual-specificity phosphatases is represented by several isoforms found in both resting and activated macrophages. The main substrate of dual-specificity phosphatases are three components of mitogen-activated kinase signaling cascades: the extracellular signal-regulated kinase ERK1/2, p38, and Janus kinase family. The results of the study of model tumor-associated macrophages supported the assumption of the crucial role of dual-specificity phosphatases in the formation and determination of the outcome of the immune response against tumor cells through the selective suppression of mitogen-activated kinase signaling cascades. Since mitogen-activated kinases mostly activate the production of pro-inflammatory mediators and the antitumor function of macrophages, the excess activity of dual-specificity phosphatases suppresses the ability of tumor-associated macrophages to activate the antitumor immune response. Nowadays, the fundamental research in tumor immunology is focused on the search for novel molecular targets to activate the antitumor immune response. However, to date, dual-specificity phosphatases received limited discussion as key targets of the immune system to activate the antitumor immune response. This review discusses the importance of dual-specificity phosphatases as key regulators of the tumor-associated macrophage function.

Down-regulated TAB1 suppresses the replication of Coxsackievirus B5 via activating the NF-κB pathways through interaction with viral 3D polymerase

Coxsackievirus Group B type 5 (CVB5), an important pathogen of hand-foot-mouth disease, is also associated with neurological complications and poses a public health threat to young infants. Among the CVB5 proteins, the nonstructural protein 3D, known as the Enteroviral RNA-dependent RNA polymerase, is mainly involved in viral genome replication and transcription. In this study, we performed immunoprecipitation coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) to identify host proteins that interacted with CVB5 3D polymerase. A total of 116 differentially expressed proteins were obtained. Gene Ontology analysis identified that the proteins were involved in cell development and cell adhesion, distributed in the desmosome and envelope, and participated in GTPase binding. Kyoto Encyclopedia of Genes and Genomes analysis further revealed they participated in nerve diseases, such as Parkinson disease. Among them, 35 proteins were significantly differentially expressed and the cellular protein TGF-BATA-activated kinase1 binding protein 1 (TAB1) was found to be specifically interacting with the 3D polymerase. 3D polymerase facilitated the entry of TAB1 into the nucleus and down-regulated TAB1 expression via the lysosomal pathway. In addition, TAB1 inhibited CVB5 replication via inducing inflammatory factors and activated the NF-κB pathway through IκBα phosphorylation. Moreover, the 90-96aa domain of TAB1 was an important structure for the function. Collectively, our findings demonstrate the mechanism by which cellular TAB1 inhibits the CVB5 replication via activation of the host innate immune response, providing a novel insight into the virus-host innate immunity.

Riding the wave of innovation: immunoinformatics in fish disease control

The spread of infectious illnesses has been a significant factor restricting aquaculture production. To maximise aquatic animal health, vaccination tactics are very successful and cost-efficient for protecting fish and aquaculture animals against many disease pathogens. However, due to the increasing number of immunological cases and their complexity, it is impossible to manage, analyse, visualise, and interpret such data without the assistance of advanced computational techniques. Hence, the use of immunoinformatics tools is crucial, as they not only facilitate the management of massive amounts of data but also greatly contribute to the creation of fresh hypotheses regarding immune responses. In recent years, advances in biotechnology and immunoinformatics have opened up new research avenues for generating novel vaccines and enhancing existing vaccinations against outbreaks of infectious illnesses, thereby reducing aquaculture losses. This review focuses on understanding in silico epitope-based vaccine design, the creation of multi-epitope vaccines, the molecular interaction of immunogenic vaccines, and the application of immunoinformatics in fish disease based on the frequency of their application and reliable results. It is believed that it can bridge the gap between experimental and computational approaches and reduce the need for experimental research, so that only wet laboratory testing integrated with in silico techniques may yield highly promising results and be useful for the development of vaccines for fish.

A Narrative Review of Cytokine Networks: Pathophysiological and Therapeutic Implications for Inflammatory Bowel Disease Pathogenesis

Inflammatory bowel disease (IBD) is a lifelong inflammatory immune mediated disorder, encompassing Crohn's disease (CD) and ulcerative colitis (UC); however, the cause and specific pathogenesis of IBD is yet incompletely understood. Multiple cytokines produced by different immune cell types results in complex functional networks that constitute a highly regulated messaging network of signaling pathways. Applying biological mechanisms underlying IBD at the single omic level, technologies and genetic engineering enable the quantification of the pattern of released cytokines and new insights into the cytokine landscape of IBD. We focus on the existing literature dealing with the biology of pro- or anti-inflammatory cytokines and interactions that facilitate cell-based modulation of the immune system for IBD inflammation. We summarize the main roles of substantial cytokines in IBD related to homeostatic tissue functions and the remodeling of cytokine networks in IBD, which may be specifically valuable for successful cytokine-targeted therapies via marketed products. Cytokines and their receptors are validated targets for multiple therapeutic areas, we review the current strategies for therapeutic intervention and developing cytokine-targeted therapies. New biologics have shown efficacy in the last few decades for the management of IBD; unfortunately, many patients are nonresponsive or develop therapy resistance over time, creating a need for novel therapeutics. Thus, the treatment options for IBD beyond the immune-modifying anti-TNF agents or combination therapies are expanding rapidly. Further studies are needed to fully understand the immune response, networks of cytokines, and the direct pathogenetic relevance regarding individually tailored, safe and efficient targeted-biotherapeutics.

Regulation of anti-inflammatory and antioxidant responses by methanol extract of Mikania cordata (Burm. f.) B. L. Rob. leaves via the inactivation of NF-κB and MAPK signaling pathways and activation of Nrf2 in LPS-induced RAW 264.7 macrophages

Mikania cordata (Burm. f.) B.L. Rob. has been traditionally used in tropical countries throughout Asia and Africa to treat gastric ulcers, dyspepsia, and dysentery. However, the mechanisms responsible for its anti-inflammatory and antioxidant activities are not fully understood. Therefore, this study sought to investigate the anti-inflammatory and antioxidant effects of methanol extracts of M. cordata (MMC) on inflammation and oxidative stress in lipopolysaccharide (LPS)-stimulated murine RAW 264.7 macrophages and elucidate its underlying regulatory mechanism. MMC significantly suppressed the production of nitric oxide (NO) and prostaglandin E2 (PGE2) in LPS-stimulated RAW 264.7 macrophages by downregulating the expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) at both the mRNA and protein levels. Moreover, MMC effectively reduced the mRNA expression levels and production of pro-inflammatory cytokines, including interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α (TNF-α). These suppressive effects of MMC on pro-inflammatory mediators and cytokines were mediated through the inhibition of transforming growth factor beta-activated kinase 1 (TAK1), which subsequently blocked the activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs). MMC also upregulated the nuclear factor erythroid-2-related factor 2 (Nrf2) by inducing the degradation of Kelch-like ECH-related protein 1 (Keap1), an Nrf2-specific E3 ligase. Accordingly, MMC enhanced Nrf2 target gene expression of anti-oxidative regulators such as heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase 1 (NQO1). However, it had minimal effect on the DPPH radical scavenging capacity in vitro. Collectively, these findings demonstrate that MMC holds promise as a potential therapeutic agent for alleviating inflammation-related diseases and oxidative stress.

Targeting CaN/NFAT in Alzheimer's brain degeneration

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a progressive loss of cognitive functions. While the exact causes of this debilitating disorder remain elusive, numerous investigations have characterized its two core pathologies: the presence of β-amyloid plaques and tau tangles. Additionally, multiple studies of postmortem brain tissue, as well as results from AD preclinical models, have consistently demonstrated the presence of a sustained inflammatory response. As the persistent immune response is associated with neurodegeneration, it became clear that it may also exacerbate other AD pathologies, providing a link between the initial deposition of β-amyloid plaques and the later development of neurofibrillary tangles. Initially discovered in T cells, the nuclear factor of activated T-cells (NFAT) is one of the main transcription factors driving the expression of inflammatory genes and thus regulating immune responses. NFAT-dependent production of inflammatory mediators is controlled by Ca2+-dependent protein phosphatase calcineurin (CaN), which dephosphorylates NFAT and promotes its transcriptional activity. A substantial body of evidence has demonstrated that aberrant CaN/NFAT signaling is linked to several pathologies observed in AD, including neuronal apoptosis, synaptic deficits, and glia activation. In view of this, the role of NFAT isoforms in AD has been linked to disease progression at different stages, some of which are paralleled to diminished cognitive status. The use of classical inhibitors of CaN/NFAT signaling, such as tacrolimus or cyclosporine, or adeno-associated viruses to specifically inhibit astrocytic NFAT activation, has alleviated some symptoms of AD by diminishing β-amyloid neurotoxicity and neuroinflammation. In this article, we discuss the recent findings related to the contribution of CaN/NFAT signaling to the progression of AD and highlight the possible benefits of targeting this pathway in AD treatment.

USP38 regulates inflammatory cardiac remodeling after myocardial infarction

BACKGROUND

The inflammatory response and subsequent ventricular remodeling are key factors contributing to ventricular arrhythmias (VAs) after myocardial infarction (MI). Ubiquitin-specific protease 38 (USP38) is a member of the USP family, but the impact of USP38 in arrhythmia substrate generation after MI remains unclear. This study aimed to determine the role of USP38 in post-MI VAs and its underlying mechanisms.

METHODS AND RESULTS

Surgical left descending coronary artery ligation was used to construct MI models. Morphological, biochemical, histological, and electrophysiological studies and molecular analyses were performed after MI on days 3 and 28. We found that the USP38 expression was remarkably increased after MI. Cardiac-conditional USP38 knockout (USP38-CKO) reduces the expression of the inflammatory marker CD68 as well as the inflammatory factors TNF-α and IL-1β after MI, thereby alleviating advanced cardiac fibrosis, electrical remodeling, ion channel remodeling, and susceptibility to VAs. In contrast, cardiac-specific USP38 overexpression (USP38-TG) showed a significant opposite effect, exacerbating the early inflammatory response and cardiac remodeling after MI. Mechanistically, USP38 knockout inhibited activation of the TAK1/NF-κB signaling pathway after MI, whereas USP38 overexpression enhanced activation of the TAK1/NF-κB signaling pathway after MI.

CONCLUSIONS

Our study confirms that USP38-CKO attenuates the inflammatory response, improves ventricular remodeling after myocardial infarction, and reduces susceptibility to malignant VA by inhibiting the activation of the TAK1/NF-κB pathway, with USP38-TG playing an opposing role. These results suggest that USP38 may be an important target for the treatment of cardiac remodeling and arrhythmias after MI.

Evaluation of the Effect and Mechanism of Sanhuang Ointment on MRSA Infection in the Skin and Soft Tissue via Network Pharmacology

Introduction

Skin and soft tissue infection (SSTI) is a frequently encountered clinical disease, and Sanhuang ointment, a traditional Chinese medicine, is used to treat it. However, the pharmacological effect of Sanhuang ointment on SSTI and its underlying mechanism remains unclear. Here, we investigate the protective effect of Sanhuang ointment on Methicillin-resistant Staphylococcus aureus (MRSA) infection in the skin and soft tissues and the underlying mechanism by network pharmacological analysis, followed by in vivo experimental validation.

Methods

Via network pharmacology, the active components and disease targets of Sanhuang ointment were screened and intersected for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. A rat model of skin and soft tissue infection was established, and pathological features were observed. Large, medium, and small-dose groups (1 g, 0.5 g, and 0.25 g/animal, with the total amount of Vaseline, dispensed 1 g/animal) of Sanhuang ointment were prepared and Mupirocin ointment was used as a positive control (0.5 g/animal, with the total amount of Vaseline, dispensed 1 g/animal). The expressions of key proteins of the IL-17/NF-κB signaling pathway and downstream inflammatory factors were analyzed by histomorphological analysis, enzyme-linked immunosorbent assay, polymerase chain reaction, and Western blotting.

Results

In all, 119 active components and 275 target genes of Sanhuang ointment were identified and intersected with MRSA infection-related genes via network pharmacology analysis, and 34 target genes of Sanhuang ointment were found to be involved in skin and soft tissue infections with MRSA. Sanhuang ointment (1 g/mouse) could effectively ameliorate histopathological changes and significantly inhibit the expression of key proteins involved in the IL-17/NF-κB signaling pathway and downstream inflammatory factors (p < 0.05).

Conclusion

Sanhuang ointment has a protective effect on MRSA infection and inhibits inflammation by inhibiting the IL-17/NF-κB signaling pathway. Our findings are important for the secondary development and new drug development of Sanhuang ointment.

Novel Therapeutic Avenues for Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is a complicated, heterogeneous genetic condition that causes left ventricular hypertrophy, fibrosis, hypercontractility, and decreased compliance. Despite the advances made over the past 3 decades in understanding the molecular and cellular mechanisms aggravating HCM, the relationship between pathophysiological stress stimuli and distinctive myocyte growth profiles is still imprecise. Currently, mavacamten, a selective and reversible inhibitor of cardiac myosin ATPase, is the only drug approved by the US FDA for the treatment of HCM. Thus, there is an unmet need for developing novel disease-specific therapeutic approaches. This article provides an overview of emerging therapeutic targets for the treatment of HCM based on various molecular pathways and novel developments that are hopefully soon to enter the clinical study. These newly discovered targets include the dual specificity tyrosine-phosphorylation-regulated kinase 1B, the absence of the melanoma 1 inflammasome, the leucine-rich repeat kinase 2 enzyme, and the cluster of differentiation 147.

Taurine reduction of injury from neutrophil infiltration ameliorates Streptococcus uberis-induced mastitis

Mastitis is a common disease of dairy cows characterized by infiltration of leukocytes, especially neutrophils, resulting in increased permeability of the blood-milk barrier (BMB). Taurine, a functional nutrient, has been shown to have anti-inflammatory and antioxidant effects. Here, we investigated the regulatory effects and mechanisms of taurine on the complex immune network of the mammary gland in Streptococcus uberis (S. uberis) infection. We found that taurine had no direct effect on CXCL2-mediated neutrophil chemotaxis. However, it inhibited MAPK and NF-κB signalings by modulating the activity of TAK1 downstream of TLR2, thereby reducing CXCL2 expression in macrophages to reduce neutrophil recruitment in S. uberis infection. Further, the AMPK/Nrf2 signaling pathway was activated by taurine to help mitigate oxidative damage, apoptosis and disruption of tight junctions in mammary epithelial cells caused by hypochlorous acid, a strong oxidant produced by neutrophils, thus protecting the integrity of the mammary epithelial barrier. Taurine protects the BMB from damage caused by neutrophils via blocking the macrophage-CXCL2-neutrophil signaling axis and increasing the antioxidant capacity of mammary epithelial cells.

RIPK1 and RIPK3 inhibitors: potential weapons against inflammation to treat diabetic complications

Diabetes mellitus is a metabolic disease that is characterized by chronic hyperglycemia due to a variety of etiological factors. Long-term metabolic stress induces harmful inflammation leading to chronic complications, mainly diabetic ophthalmopathy, diabetic cardiovascular complications and diabetic nephropathy. With diabetes complications being one of the leading causes of disability and death, the use of anti-inflammatories in combination therapy for diabetes is increasing. There has been increasing interest in targeting significant regulators of the inflammatory pathway, notably receptor-interacting serine/threonine-kinase-1 (RIPK1) and receptor-interacting serine/threonine-kinase-3 (RIPK3), as drug targets for managing inflammation in treating diabetes complications. In this review, we aim to provide an up-to-date summary of current research on the mechanism of action and drug development of RIPK1 and RIPK3, which are pivotal in chronic inflammation and immunity, in relation to diabetic complications which may be benefit for explicating the potential of selective RIPK1 and RIPK3 inhibitors as anti-inflammatory therapeutic agents for diabetic complications.

N6-methyladenosine methylation in kidney injury

Multiple mechanisms are involved in kidney damage, among which the role of epigenetic modifications in the occurrence and development of kidney diseases is constantly being revealed. However, N6-methyladenosine (M6A), a well-known post-transcriptional modification, has been regarded as the most prevalent epigenetic modifications in higher eukaryotic, which is involved in various biological processes of cells such as maintaining the stability of mRNA. The role of M6A modification in the mechanism of kidney damage has attracted widespread attention. In this review, we mainly summarize the role of M6A modification in the progression of kidney diseases from the following aspects: the regulatory pattern of N6-methyladenosine, the critical roles of N6-methyladenosine in chronic kidney disease, acute kidney injury and renal cell carcinoma, and then reveal its potential significance in the diagnosis and treatment of various kidney diseases. A better understanding of this field will be helpful for future research and clinical treatment of kidney diseases.

Drosophila TNF/TNFRs: At the crossroad between metabolism, immunity, and tissue homeostasis

Tumor necrosis factor (TNF)-α is a highly conserved proinflammatory cytokine with important functions in immunity, tissue repair, and cellular homeostasis. Due to the simplicity of the Drosophila TNF-TNF receptor (TNFR) system and a broad genetic toolbox, the fly has played a pivotal role in deciphering the mechanisms underlying TNF-mediated physiological and pathological functions. In this review, we summarize the recent advances in our understanding of how local and systemic sources of Egr/TNF contribute to its antitumor and tumor-promoting properties, and its emerging functions in adaptive growth responses, sleep regulation, and adult tissue homeostasis. The recent annotation of TNF as an adipokine and its indisputable contribution to obesity- and cancer-associated metabolic diseases have provoked a new area of research focusing on its dual function in regulating immunity and energy homeostasis. Here, we discuss the role of TNFR signaling in coupling immune and metabolic processes and how this might be relevant in the adaption of host to environmental stresses, or, in the case of obesity, promote metabolic derangements and disease.

Macrophages immunomodulation induced by Porphyromonas gingivalis and oral antimicrobial peptides

Porphyromonas gingivalis is a keystone pathogen associated with periodontitis development, a chronic inflammatory pathology characterized by the destruction of the supporting teeth structure. Macrophages are recruited cells in the inflammatory infiltrate from patients with periodontitis. They are activated by the P. gingivalis virulence factors arsenal, promoting an inflammatory microenvironment characterized by cytokine production (TNF-α, IL-1β, IL-6), prostaglandins, and metalloproteinases (MMPs) that foster the tissular destruction characteristic of periodontitis. Furthermore, P. gingivalis suppresses the generation of nitric oxide, a potent antimicrobial molecule, through its degradation, and incorporating its byproducts as a source of energy. Oral antimicrobial peptides can contribute to controlling the disease due to their antimicrobial and immunoregulatory activity, which allows them to maintain homeostasis in the oral cavity. This study aimed to analyze the immunopathological role of macrophages activated by P. gingivalis in periodontitis and suggested using antimicrobial peptides as therapeutic agents to treat the disease.

The Impact of ETV6-NTRK3 Oncogenic Gene Fusions on Molecular and Signaling Pathway Alterations

Chromosomal translocations creating fusion genes are common cancer drivers. The oncogenic ETV6-NTRK3 (EN) gene fusion joins the sterile alpha domain of the ETV6 transcription factor with the tyrosine kinase domain of the neurotrophin-3 receptor NTRK3. Four EN variants with alternating break points have since been detected in a wide range of human cancers. To provide molecular level insight into EN oncogenesis, we employed a proximity labeling mass spectrometry approach to define the molecular context of the fusions. We identify in total 237 high-confidence interactors, which link EN fusions to several key signaling pathways, including ERBB, insulin and JAK/STAT. We then assessed the effects of EN variants on these pathways, and showed that the pan NTRK inhibitor Selitrectinib (LOXO-195) inhibits the oncogenic activity of EN2, the most common variant. This systems-level analysis defines the molecular framework in which EN oncofusions operate to promote cancer and provides some mechanisms for therapeutics.

RNF167-mediated ubiquitination of Tollip inhibits TNF-α-triggered NF-κB and MAPK activation

Toll-interacting protein (Tollip) is a multifunctional regulator in cellular activities. However, whether its functions are subjected to post-translational modifications remains elusive. Here, we identified ubiquitination as a post-translational modification on Tollip. We found that Tollip interacted with ring finger protein 167 (RNF167) through its C-terminal coupling of ubiquitin to ER degradation (CUE) domain, and RNF167 functioned as the potential E3 ligase to attach K33-linked poly-ubiquitin chains to the Lys235 (K235) site of Tollip. Furthermore, we discovered Tollip could inhibit TNF-α-induced nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) activation, and substitution of Lys235 on Tollip to arginine failed to suppress TNF-α-NF-κB/MAPK (JNK) cascades, revealing the role of Tollip and its ubiquitination in NF-κB/MAPK pathways. Thus, our study reveals the novel biological function of Tollip and RNF167-dependent ubiquitination of Tollip in TNF-α signaling.

Mitogen-Activated Protein Kinases (MAPKs) and Enteric Bacterial Pathogens: A Complex Interplay

Diverse extracellular and intracellular cues activate mammalian mitogen-activated protein kinases (MAPKs). Canonically, the activation starts at cell surface receptors and continues via intracellular MAPK components, acting in the host cell nucleus as activators of transcriptional programs to regulate various cellular activities, including proinflammatory responses against bacterial pathogens. For instance, binding host pattern recognition receptors (PRRs) on the surface of intestinal epithelial cells to bacterial pathogen external components trigger the MAPK/NF-κB signaling cascade, eliciting cytokine production. This results in an innate immune response that can eliminate the bacterial pathogen. However, enteric bacterial pathogens evolved sophisticated mechanisms that interfere with such a response by delivering virulent proteins, termed effectors, and toxins into the host cells. These proteins act in numerous ways to inactivate or activate critical components of the MAPK signaling cascades and innate immunity. The consequence of such activities could lead to successful bacterial colonization, dissemination, and pathogenicity. This article will review enteric bacterial pathogens' strategies to modulate MAPKs and host responses. It will also discuss findings attempting to develop anti-microbial treatments by targeting MAPKs.

Pharmacological inhibition of TAK1 prevents and induces regression of experimental organ fibrosis

Multiorgan fibrosis in systemic sclerosis (SSc) accounts for substantial mortality and lacks effective therapies. Lying at the crossroad of TGF-β and TLR signaling, TGF-β-activated kinase 1 (TAK1) might have a pathogenic role in SSc. We therefore sought to evaluate the TAK1 signaling axis in patients with SSc and to investigate pharmacological TAK1 blockade using a potentially novel drug-like selective TAK1 inhibitor, HS-276. Inhibiting TAK1 abrogated TGF-β1 stimulation of collagen synthesis and myofibroblasts differentiation in healthy skin fibroblasts, and it ameliorated constitutive activation of SSc skin fibroblasts. Moreover, treatment with HS-276 prevented dermal and pulmonary fibrosis and reduced the expression of profibrotic mediators in bleomycin-treated mice. Importantly, initiating HS-276 treatment even after fibrosis was already established prevented its progression in affected organs. Together, these findings implicate TAK1 in the pathogenesis of SSc and identify targeted TAK1 inhibition using a small molecule as a potential strategy for the treatment of SSc and other fibrotic diseases.

Glutathione trisulfide prevents lipopolysaccharide-induced retinal inflammation via inhibition of proinflammatory cytokine production in glial cells

We aimed to investigate the impact of glutathione trisulfide (GSSSG) on lipopolysaccharide (LPS)-induced inflammation in retinal glia. Inflammatory responses in mouse-derived glial cells and Wistar rat retinas were stimulated with administration of LPS. Cell survival and proinflammatory cytokine production were examined using the Calcein-AM assay, and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Retinal microglia were visualized with immunohistochemistry for Iba1. Administration of LPS (10 µg/mL) or GSSSG (less than 100 µM) did not affect survival of cultured primary Müller cells and established microglial cells (BV-2). RT-qPCR and ELISA indicated that GSSSG inhibited LPS-induced gene upregulation and protein secretion of proinflammatory cytokines in these glial cells and rat retinas. GSSSG inhibited LPS-induced activation of TGF-β-activated kinase 1 (TAK1), which is an upstream kinase of NF-κB, in BV-2 cells. Finally, in vivo experiments indicated that intravitreal administration of GSSSG but not its relative glutathione disulfide (GSSG) inhibited LPS (500 ng)-induced accumulation of Iba1-immunopositive microglia in rat retinas. Taken together, GSSSG has the potential to prevent pathogenesis of inflammation-associated ocular diseases by inhibiting proinflammatory cytokine expression in retinal glial cells.

β-arrestin 2 negatively regulates lung cancer progression by inhibiting the TRAF6 signaling axis for NF-κB activation and autophagy induced by TLR3 and TLR4

β-arrestin 2 (ARRB2) is functionally implicated in cancer progression via various signaling pathways. However, its role in lung cancer remains unclear. To obtain clinical insight on its function in lung cancer, microarray data from lung tumor tissues (LTTs) and matched lung normal tissues (mLNTs) of primary non-small cell lung cancer (NSCLC) patients (n = 37) were utilized. ARRB2 expression levels were markedly decreased in all 37 LTTs compared to those in matched LNTs of NSCLC patients. They were significantly co-related to enrichment gene sets associated with oncogenic and cancer genes. Importantly, Gene Set Enrichment Analysis (GSEA) between three LTTs with highly down-regulated ARRB2 and three LTTs with lowly down-regulated ARRB2 revealed significant enrichments related to toll-like receptor (TLR) signaling and autophagy genes in three LTTs with highly down-regulated ARRB2, suggesting that ARRB2 was negatively involved in TLR-mediated signals for autophagy induction in lung cancer. Biochemical studies for elucidating the molecular mechanism revealed that ARRB2 interacted with TNF receptor-associated factor 6 (TRAF6) and Beclin 1 (BECN1), thereby inhibiting the ubiquitination of TRAF6-TAB2 to activate NF-κB and TRAF6-BECN1 for autophagy stimulated by TLR3 and TLR4, suggesting that ARRB2 could inhibit the TRAF6-TAB2 signaling axis for NF-κB activation and TRAF6-BECN1 signaling axis for autophagy in response to TLR3 and TLR4. Notably, ARRB2-knockout (ARRB2KO) lung cancer cells exhibited marked enhancements of cancer migration, invasion, colony formation, and proliferation in response to TLR3 and TLR4 stimulation. Altogether, our current data suggest that ARRB2 can negatively regulate lung cancer progression by inhibiting TLR3- and TLR4-induced autophagy.

Novel therapeutic targets to halt the progression of Parkinson's disease: an in-depth review on molecular signalling cascades

Recent research has focused mostly on understanding and combating the neurodegenerative mechanisms and symptoms of Parkinson's disease (PD). Moreover, developing novel therapeutic targets to halt the progression of PD remains a key focus for researchers. As yet, no agents have been found to have unambiguous evidence of disease-modifying actions in PD. The primary objective of this review is to summarize the promising targets that have recently been uncovered which include histamine 4 receptors, beta2 adrenergic receptor, phosphodiesterase 4, sphingosine-1-phosphate receptor subtype 1, angiotensin receptors, high-mobility group box 1, rabphilin-3A, purinergic 2Y type 12 receptor, colony-stimulating factor-1 receptor, transient receptor potential vanilloid 4, alanine-serine-cysteine transporter 2, G protein-coupled oestrogen receptor, a mitochondrial antiviral signalling protein, glucocerebrosidase, indolamine-2,3-dioxygenase-1, soluble epoxy hydroxylase and dual specificity phosphatase 6. We have also reviewed the molecular signalling cascades of those novel targets which cause the initiation and progression of PD and gathered some emerging disease-modifying agents that could slow the progression of PD. These approaches will assist in the discovery of novel target molecules, for curing disease symptoms and may provide a glimmer of hope for the treatment of PD. As of now, there is no drug available that will completely prevent the progression of PD by inhibiting the pathogenesis involved in PD, and thus, the newer targets and their inhibitors or activators are the major focus for researchers to suppress PD symptomatology. And the major limitations of these targets are the lack of clinical data and less number pre-clinical data, as we have majorly discussed the different targets which all have well reported for other disease pathogenesis. Thus, finding the disease-drug interactions, the molecular mechanisms, and the major side effects will be major challenges for the researchers.

Bacterial effector restricts liquid-liquid phase separation of ZPR1 to antagonize host UPRER

How pathogens manipulate host UPR^ER to mediate immune evasion is largely unknown. Here, we identify the host zinc finger protein ZPR1 as an interacting partner of the enteropathogenic E. coli (EPEC) effector NleE using proximity-enabled protein crosslinking. We show that ZPR1 assembles via liquid-liquid phase separation (LLPS) in vitro and regulates CHOP-mediated UPR^ER at the transcriptional level. Interestingly, in vitro studies show that the ZPR1 binding ability with K63-ubiquitin chains, which promotes LLPS of ZPR1, is disrupted by NleE. Further analyses indicate that EPEC restricts host UPR^ER pathways at the transcription level in a NleE-ZPR1 cascade-dependent manner. Together, our study reveals the mechanism by which EPEC interferes with CHOP-UPR^ER via regulating ZPR1 to help pathogens escape host defense.

PSMD13 inhibits NF-κB pathway by targeting TAK1 for K63-linked ubiquitination in miiuy croaker (Miichthys miiuy)

ransforming growth factor-β activated kinase (TAK) 1 is an adaptor molecular in the TLR-mediated NF-κB pathway which has been implicated in the regulation of a wide range of physiological and pathological processes. Proteasome 26S subunit, non-ATPases (PSMD) 13 is essential for the structural maintenance and function of the 26S proteasome. However, the mechanism of PSMD13 in innate immune regulation is not clear. In this study, the expression of PSMD13 mRNA was significantly increased under Vibrio harveyi stimulation, and PSMD13 inhibited the NF-κB pathway by targeting TAK1. Mechanically, PSMD13 significantly inhibited the K63-linked ubiquitination of TAK1, thereby inhibiting the expression of TAK1. Moreover, this discovery enriches the research of the PSMD family regulating the innate immune response and provides a new idea for the study of the mammalian innate immune regulation mechanism.

Targeted regulation of TAK1 counteracts dystrophinopathy in a DMD mouse model

Muscular dystrophies make up a group of genetic neuromuscular disorders that involve severe muscle wasting. TGF-β-activated kinase 1 (TAK1) is an important signaling protein that regulates cell survival, growth, and inflammation. TAK1 has been recently found to promote myofiber growth in the skeletal muscle of adult mice. However, the role of TAK1 in muscle diseases remains poorly understood. In the present study, we have investigated how TAK1 affects the progression of dystrophic phenotype in the mdx mouse model of Duchenne muscular dystrophy (DMD). TAK1 is highly activated in the dystrophic muscle of mdx mice during the peak necrotic phase. While targeted inducible inactivation of TAK1 inhibits myofiber injury in young mdx mice, it results in reduced muscle mass and contractile function. TAK1 inactivation also causes loss of muscle mass in adult mdx mice. By contrast, forced activation of TAK1 through overexpression of TAK1 and TAB1 induces myofiber growth without having any deleterious effect on muscle histopathology. Collectively, our results suggest that TAK1 is a positive regulator of skeletal muscle mass and that targeted regulation of TAK1 can suppress myonecrosis and ameliorate disease progression in DMD.

E3 ligase RNF99 negatively regulates TLR-mediated inflammatory immune response via K48-linked ubiquitination of TAB2

Innate immunity is the first line to defend against pathogenic microorganisms, and Toll-like receptor (TLR)-mediated inflammatory responses are an essential component of innate immunity. However, the regulatory mechanisms of TLRs in innate immunity remain unperfected. We found that the expression of E3 ligase Ring finger protein 99 (RNF99) decreased significantly in peripheral blood monocytes from patients infected with Gram negative bacteria (G-) and macrophages stimulated by TLRs ligands, indicating the role of RNF99. We also demonstrated for the first time, the protective role of RNF99 against LPS-induced septic shock and dextran sodium sulfate (DSS)-induced colitis using RNF99 knockout mice (RNF99-/-) and bone marrow-transplanted mice. In vitro experiments revealed that RNF99 deficiency significantly promoted TLR-mediated inflammatory cytokine expression and activated the NF-κB and MAPK pathways in macrophages. Mechanistically, in both macrophages and HEK293 cell line with TLR4 stably transfection, RNF99 interacted with and degraded TAK1-binding protein (TAB) 2, a regulatory protein of the kinase TAK1, via the lysine (K)48-linked ubiquitin-proteasomal pathway on lysine 611 of TAB2, which further regulated the TLR-mediated inflammatory response. Overall, these findings indicated the physiological significance of RNF99 in macrophages in regulating TLR-mediated inflammatory reactions. It provided new insight into TLRs signal transduction, and offered a novel approach for preventing bacterial infections, endotoxin shock, and other inflammatory ills.

Emerging role of TAK1 in the regulation of skeletal muscle mass

Maintenance of skeletal muscle mass and strength throughout life is crucial for heathy living and longevity. Several signaling pathways have been implicated in the regulation of skeletal muscle mass in adults. TGF-β-activated kinase 1 (TAK1) is a key protein, which coordinates the activation of multiple signaling pathways. Recently, it was discovered that TAK1 is essential for the maintenance of skeletal muscle mass and myofiber hypertrophy following mechanical overload. Forced activation of TAK1 in skeletal muscle causes hypertrophy and attenuates denervation-induced muscle atrophy. TAK1-mediated signaling in skeletal muscle promotes protein synthesis, redox homeostasis, mitochondrial health, and integrity of neuromuscular junctions. In this article, we have reviewed the role and potential mechanisms through which TAK1 regulates skeletal muscle mass and growth. We have also proposed future areas of research that could be instrumental in exploring TAK1 as therapeutic target for improving muscle mass in various catabolic conditions and diseases.

Chlamydia trachomatis antigen induces TLR4-TAB1-mediated inflammation, but not cell death, in maternal decidua cells

BACKGROUND

During gestation, the decidua is an essential layer of the maternal-fetal interface, providing immune support and maintaining inflammatory homeostasis. Although Chlamydia (C.) trachomatis is associated with adverse pregnancy outcomes the pathogenic effects on maternal decidua contributing to adverse events are not understood. This study examined how C. trachomatis antigen affects cell signaling, cell death, and inflammation in the decidua.

METHODS

Primary decidua cells (pDECs) from term, not-in-labor, fetal membrane-decidua were cultured using the following conditions: (1) control - standard cell culture conditions, (2) 100 ng/ml or (3) 200 ng/ml of C. trachomatis antigen to model decidual cell infection in vitro. Differential expression of Toll-like receptor (TLR) 4 (receptor for C. trachomatis antigen), signaling pathway markers phosphorylated TGF-Beta Activated Kinase 1 (PTAB1), TAB1, phosphorylated p38 mitogen-activated protein kinases (Pp38 MAPK), and p38 MAPK (western blot), decidual cell apoptosis and necrosis (flow cytometry), and inflammation (ELISA for cytokines) were determined in cells exposed to C. trachomatis antigen. T-test was used to assess statistical significance (p < 0.05).

RESULTS

C. trachomatis antigen significantly induced expression of TLR4 (p = 0.03) and activation of TAB1 (p = 0.02) compared to controls. However, it did not induce p38 MAPK activation. In addition, pDECs maintained their stromal cell morphology when exposed to C. trachomatis antigen showing no signs of apoptosis and/or necrosis but did induce pro-inflammatory cytokine interleukin (IL)-6 (100 ng/ml: p = 0.02 and 200 ng/ml: p = 0.03), in pDECs compared to controls.

CONCLUSION

Prenatal C. trachomatis infection can produce antigens that induce TLR4-TAB1 signaling and IL-6 inflammation independent of Pp38 MAPK and apoptosis and necrosis. This suggests that C. trachomatis can imbalance decidual inflammatory homeostasis, potentially contributing to adverse events during pregnancy.

The roles of E3 ubiquitin ligases in cancer progression and targeted therapy

Ubiquitination is one of the most important post-translational modifications which plays a significant role in conserving the homeostasis of cellular proteins. In the ubiquitination process, ubiquitin is conjugated to target protein substrates for degradation, translocation or activation, dysregulation of which is linked to several diseases including various types of cancers. E3 ubiquitin ligases are regarded as the most influential ubiquitin enzyme owing to their ability to select, bind and recruit target substrates for ubiquitination. In particular, E3 ligases are pivotal in the cancer hallmarks pathways where they serve as tumour promoters or suppressors. The specificity of E3 ligases coupled with their implication in cancer hallmarks engendered the development of compounds that specifically target E3 ligases for cancer therapy. In this review, we highlight the role of E3 ligases in cancer hallmarks such as sustained proliferation via cell cycle progression, immune evasion and tumour promoting inflammation, and in the evasion of apoptosis. In addition, we summarise the application and the role of small compounds that target E3 ligases for cancer treatment along with the significance of targeting E3 ligases as potential cancer therapy.

Xanthine oxidoreductase mediates genotoxic drug-induced autophagy and apoptosis resistance by uric acid accumulation and TGF-β-activated kinase 1 (TAK1) activation

Autophagy is a highly conserved cellular process that profoundly impacts the efficacy of genotoxic chemotherapeutic drugs. TGF-β-activated kinase 1 (TAK1) is a serine/threonine kinase that activates several signaling pathways involved in inducing autophagy and suppressing cell death. Xanthine oxidoreductase (XOR) is a rate-limiting enzyme that converts hypoxanthine to xanthine, and xanthine to uric acid and hydrogen peroxide in the purine catabolism pathway. Recent studies showed that uric acid can bind to TAK1 and prolong its activation. We hypothesized that genotoxic drugs may induce autophagy and apoptosis resistance by activating TAK1 through XOR-generated uric acid. Here, we report that gemcitabine and 5-fluorouracil (5-FU), two genotoxic drugs, induced autophagy in HeLa and HT-29 cells by activating TAK1 and its two downstream kinases, AMP-activated kinase (AMPK) and c-Jun terminal kinase (JNK). XOR knockdown and the XOR inhibitor allopurinol blocked gemcitabine-induced TAK1, JNK, AMPK, and Unc51-like kinase 1 (ULK1)^S555 phosphorylation and gemcitabine-induced autophagy. Inhibition of the ATM-Chk pathway, which inhibits genotoxic drug-induced uric acid production, blocked gemcitabine-induced autophagy by inhibiting TAK1 activation. Exogenous uric acid in its salt form, monosodium urate (MSU), induced autophagy by activating TAK1 and its downstream kinases JNK and AMPK. Gene knockdown or the inhibitors of these kinases blocked gemcitabine- and MSU-induced autophagy. Inhibition of autophagy by allopurinol, chloroquine, and 5Z-7-oxozeaenol (5Z), a TAK1-specific inhibitor, enhanced gemcitabine-induced apoptosis. Our study uncovers a previously unrecognized role of XOR in regulating genotoxic drug-induced autophagy and apoptosis and has implications for designing novel therapeutic strategies for cancer treatment.

Hsa_circ_0021727 (circ-CD44) promotes ESCC progression by targeting miR-23b-5p to activate the TAB1/NFκB pathway

Esophageal squamous cell carcinoma (ESCC) is characterized by high morbidity and mortality. Circular RNAs (circRNAs) play an important role in tumor progression. We discovered an aberrantly expressed circRNA (hsa_circ_0021727) in patients with ESCC. However, the mechanism of action of hsa_circ_0021727 in tumors is unclear. The present study aimed to investigate the biological role of hsa_circ_0021727 and its mechanism in ESCC progression. We screened for the expression of hsa_circ_0021727 in ESCC patients. Patients with ESCC with high expression of hsa_circ_0021727 had shorter survival than those with low expression. Hsa_circ_0021727 promoted the proliferation, invasion, and migration of ESCC cells. However, miR-23b-5p inhibited this ability of hsa_circ_0021727. MiR-23b-5p acts by targeting TAK1-binding protein 1 (TAB1). Upregulation of TAB1 can activate the nuclear factor kappa B (NFκB) pathway. Hsa_circ_0021727 promoted ESCC progression by activating TAB1/NFκB pathway by sponging miR-23b-5p. In addition, in vivo experiments also confirmed that hsa_circ_0021727 could promote the proliferation, invasion, and migration of ESCC cells. In short, hsa_circ_0021727 promotes ESCC progression by targeting miR-23b-5p to activate the TAB1/NFκB pathway. These findings might provide potential targets to treat ESCC.