NF-κB Nuclear Translocation Research Articles

Targeting STING oligomerization with licochalcone D ameliorates STING-driven inflammatory diseases.

The development of STING inhibitors for the treatment of STING-related inflammatory diseases continues to encounter significant challenges. The activation of STING is a multi-step process that includes binding with cGAMP, self-oligomerization, and translocation from the endoplasmic reticulum to the Golgi apparatus, ultimately inducing the expression of IRF3 and NF-κB-mediated interferons and inflammatory cytokines. It has been demonstrated that disruption of any of these steps can effectively inhibit STING activation. Traditional structure-based drug screening methodologies generally focus on specific binding sites. In this study, a TransformerCPI model based on protein primary sequences and independent of binding sites is employed to identify compounds capable of binding to the STING protein. The natural product Licochalcone D (LicoD) is identified as a potent and selective STING inhibitor. LicoD does not bind to the classical ligand-binding pocket; instead, it covalently modifies the Cys148 residue of STING. This modification inhibits STING oligomerization, consequently suppressing the recruitment of TBK1 and the nuclear translocation of IRF3 and NF-κB. LicoD treatment ameliorates the inflammatory phenotype in Trex1-1- mice and inhibits the progression of DSS-induced colitis and AOM/DSS-induced colitis-associated colon cancer (CAC). In summary, this study reveals the potential of LicoD in treating STING-driven inflammatory diseases. It also demonstrates the utility of the TransformerCPI model in discovering allosteric compounds beyond the conventional binding pockets.

Role of Cathelicidins in Atherosclerosis and Associated Cardiovascular Diseases

Cathelicidins (human LL-37 and rat CRAMP) are multifunctional peptides involved in various cardiovascular conditions. This review integrates the recent findings about the functional involvement of LL-37/CRAMP across atherosclerosis, acute coronary syndrome, myocardial infarction, heart failure, diabetic cardiomyopathy, and platelet aggregation/thrombosis. In atherosclerosis, LL-37 interacts with scavenger receptors to modulate lipid metabolism and binds with mitochondrial DNA and lipoproteins. In acute coronary syndrome, LL-37 influences T cell responses and mitigates calcification within atherosclerotic plaques. During myocardial infarction and ischaemia/reperfusion injury, LL-37/CRAMP exhibits dual roles: protecting against myocardial damage through the AKT and ERK1/2 signalling pathways, while exacerbating inflammation via TLR4 and NLRP3 inflammasome activation. In heart failure, LL-37/CRAMP attenuates hypertrophy and fibrosis via NF-κB inhibition and the activation of the IGFR1/PI3K/AKT and TLR9/AMPK pathways. Moreover, in diabetic cardiomyopathy, these peptides alleviate oxidative stress and fibrosis by inhibiting TGFβ/Smad and AMPK/mTOR signalling and provide anti-inflammatory effects by reducing NF-κB nuclear translocation and NLRP3 inflammasome formation. LL-37/CRAMP also modulates platelet aggregation and thrombosis through the FPR2 and GPVI receptors, impacting apoptosis, autophagy, and other critical cellular processes. This comprehensive overview underscores LL-37/CRAMP as a promising therapeutic target in cardiovascular diseases, necessitating further elucidation of its intricate signalling networks and biological effects for clinical translation.

Monoacylglycerol lipase blockades the senescence-associated secretory phenotype by interfering with NF-κB activation and promotes docetaxel efficacy in prostate cancer.

Metabolic reprogramming and cellular senescence greatly contribute to cancer relapse and recurrence. In aging and treated prostate, persistent accumulating senescence-associated secretory phenotype (SASP) of cancer cells often limits the overall survival of patients. Novel strategic therapy with monoacylglycerol lipase (MGLL) upregulation that counters the cellular and docetaxel induced SASP might overcome this clinical challenge in prostate cancer (PCa). With primary comparative expression and survival analysis screening of fatty acid (FA) metabolism signature genes in the TCGA PCa dataset and our single center cohort, MGLL was detected to be downregulated in malignancy prostate tissues and its low expression predicted worse progression-free and overall survival. Functionally, overexpression of MGLL mainly suppresses NF-κB-driven SASP (N-SASP) which mostly restricts the cancer cell paracrine and autocrine tumorigenic manners and the corresponding cellular senescence. Further investigating metabolites, we determined that MGLL constitutive expression prevents lipid accumulation, decreases metabolites preferably, and consequently downregulates ATP levels. Overexpressed MGLL inhibited IκBα phosphorylation, NF-κB p65 phosphorylation, and NF-κB nuclear translocation to deactivate NF-κB transcriptional activities, and be responsible for the repressed N-SASP, partially through reducing ATP levels. Preclinically, combinational treatment with MGLL overexpression and docetaxel chemotherapy dramatically delays tumor progression in mouse models. Taken together, our findings identify MGLL as a switch for lipase-related N-SASP suppression and provide a potential drug candidate for promoting docetaxel efficacy in PCa.

Evaluation of Phenazine Derivatives from the Lichen-Associated Streptomyces flavidovirens as Potent Antineuroinflammatory Agents In Vitro and In Vivo.

Eighteen nitrogen-containing compounds (1-18) were isolated from cultures of the lichen-associated Streptomyces flavidovirens collected from the Qinghai-Tibet Plateau, including seven phenazine derivatives with three new ones, named subphenazines A-C (2-4), two new furan pyrrolidones (8-9), and nine known alkaloids. The structures were elucidated by spectroscopic data analysis, and absolute configurations were determined by single-crystal X-ray diffraction and ECD calculations. The phenazine-type derivatives, in particular compound 3, exhibited significantly better antineuroinflammatory activity than other isolated compounds (8-18). Compound 3 inhibited the release of proinflammatory cytokines including IL-6, TNF-α, and PGE2, and the nuclear translocation of NF-κB; it also reduced the oxidative stress and activated the Nrf2 signaling pathway in LPS-induced BV2 microglia cells. In vivo anti-inflammatory activity in zebrafish indicated that 3 inhibited LPS-stimulated ROS generation. These findings suggested that compound 3 might be a potent antineuroinflammatory agent through the regulation of the NF-κB/Nrf2 signaling pathways.

Clinacanthus nutans extract lowers periodontal inflammation under high-glucose conditions via inhibiting NF-κB signaling pathway.

Periodontal disease is more prevalent in patients with diabetes, and it has a negative impact on their quality of life. Inhibiting the infection and inflammation processes that cause periodontal disease can reduce the severity of the disease and chances of serious complications. In this study, we aimed to demonstrate the effectiveness of Clinacanthus nutans extract in reducing the inflammation in gingival fibroblast cells induced by Porphyromonas gingivalis lipopolysaccharide (LPS). Stimulation with LPS under high-glucose conditions led to increased inflammation compared to low-glucose conditions. Treatment of C. nutans extract significantly reduced the expression of these pro-inflammatory cytokines and chemokines. At a concentration of 50μg/mL, it reduced the relative expression of IL6, IL8, and CXCL10 to 0.51 ± 0.09, 0.6 ± 0.19, and 0.09 ± 0.02, respectively, compared to the non-treatment control, accompanied by a decrease in secreted protein as measured by ELISA. Additionally, application of C. nutans extract markedly suppressed the NF-κB signaling pathway by reducing the phosphorylated form of IκBα, NF-κB p65, and nuclear translocation of NF-κB, along with a decrease in COX2, a key mediator in the inflammatory pathway. Furthermore, analysis of RNA sequencing data indicated that the extract clearly reversed the gene expression changes induced by LPS. This was particularly true for the signaling mediators and inflammatory genes in response to NF-κB, JAK/STAT, and TNF signaling pathways. Our finding highlights the potential of C. nutans extract to alleviate inflammation and suggests its potential as a treatment for periodontal disease in patients with diabetes.

TRNA-derived fragment 3′tRF-AlaAGC modulates cell chemoresistance and M2 macrophage polarization via binding to TRADD in breast cancer

BackgroundDrug resistance, including Adriamycin-based therapeutic resistance, remains a challenge in breast cancer (BC) treatment. Studies have revealed that macrophages could play a pivotal role in mediating the chemoresistance of cancer cells. Accumulating evidence suggests that tRNA-Derived small RNAs (tDRs) are associated the physiological and pathological processes in multiple cancers. However, the underlying mechanisms of tDRs on chemoresistance of BC in tumor-associated macrophages remain largely unknown.MethodsThe high-throughput sequencing technique was used to screen tDRs expression profile in BC cells. Gain- and loss-of-function experiments and xenograft models were performed to verify the biological function of 3′tRF-Ala-AGC in BC cells. The CIBERSORT algorithm was used to investigate immune cell infiltration in BC tissues. To explore the role of 3′tRF-Ala-AGC in macrophages, M2 macrophages transfected with 3′tRF-Ala-AGC mimic or inhibitor were co-cultured with BC cells. Effects on Nuclear factor-κb (NF-κb) pathway were investigated by NF-κb nuclear translocation assay and western blot analysis. RNA pull-down assay was performed to identify 3′tRF-Ala-AGC interacting proteins.ResultsA 3′tRF fragment of 3′tRF-AlaAGC was screened, which is significantly overexpressed in BC specimens and Adriamycin-resistant cells. 3′tRF-AlaAGC could promote cell malignant activity and facilitate M2 polarization of macrophages in vitro and in vivo. Higher expression of M2 macrophages were more likely to have lymph node metastasis and deeper invasion in BC patients. Mechanistically, 3′tRF-AlaAGC binds Type 1-associated death domain protein (TRADD) in BC cells, and suppression of TRADD partially abolished the enhanced effect of 3′tRF-AlaAGC mimic on phenotype of M2. The NF-κb signaling pathway was activated in BC cells co-cultured with M2 macrophages transfected with 3′tRF-AlaAGC mimic.Conclusions3′tRF-AlaAGC might modulate macrophage polarization via binding to TRADD and increase the effect of M2 on promoting the chemoresistance in BC cells through NF-κb signaling pathway.

In-vitro and in-vivo studies of two-drug cocktail therapy targeting chemobrain via the Nrf2/NF-κB signaling pathway.

Today, we critically need alternative therapeutic options for chemotherapy-induced cognitive impairment (CICI), often known as chemo brain. Mitochondrial dysfunction and oxidative stress are two of the primary processes that contribute to the development of chemobrain. Therefore, the purpose of this study was to investigate how CoQ10 and berberine shield neurons from chemotherapy-induced damage in in-vitro studies and memory loss in vivo studies. For the in-vitro investigation, we employed SH-SY5Y cell lines, and for the in-vivo study, we used female Swiss albino mice divided into seven different groups. Data from in-vitro studies revealed that treatment with coenzyme Q10 (CoQ10) and berberine improved chemotherapy-induced toxicity by reducing mitochondrial and total cellular ROS, as well as apoptosis-elicited markers (caspase 3 and 9). CoQ10 and berberine therapy inhibited the nuclear translocation of NF-κB and, consequently, the subsequent expressions of NLRP3 and IL-1β, implying the prevention of inflammasome formation. Furthermore, CoQ10 and berberine therapy boosted Nrf2 levels. This is a regulator for cellular resistance to oxidants. The in vivo results showed that treatment with CoQ10 (40mg/kg) and berberine (200mg/kg) improved the behavioral alterations induced by CAF (40/4/25mg/kg) in both the Morris Water Maze (MWM) and Novel Object Recognition (NOR) tests. Furthermore, biochemical and molecular evidence revealed the antioxidant, mitochondrial restorative, and anti-inflammatory potential of CoQ10 (40mg/kg) and berberine (200mg/kg) against CAF (40/4/25mg/kg) subjected mice. In addition, the histological analysis using H&E staining and transmission electron microscopy (for mitochondrial morphology) showed that mice treated with the cocktails had an increased number of healthy neurons with intact mitochondria and a reduced presence of autophagic vacuoles in the hippocampal region of the brain. These findings back up our theory about this novel cocktail method for CAF-induced cognitive impairment.

The effects of Ganoderma leucocontextum triterpenoids treatment on the D-galactose and aluminum chloride-induced Alzheimer-like pathology in mouse brain

Ethnopharmacology relevanceGanoderma leucocontextum T.H. Li, W. Q. Deng M. Wang & H.P.Hu. is a highland herbal medicine that has been shown to nourish the nervesand prolong life. Nevertheless, there is no evidence to indicate that Ganoderma leucocontextum triterpenoids (GLTs) reduce the damage triggered by Alzheimer's disease (AD). Aim of the studyThe aim of this investigation was to ascertain the protective effects of GLTs on AD mice models and cells, as well as to look into potential pathways. Materials and methodsIn this study, the phytochemical characterization of GLTs was performed by High Performance Liquid Chromatography (HPLC) and Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS). The AD mouse model was induced by injecting intraperitoneally with D-galactose (120 mg/kg) and administering orally with aluminum chloride (20 mg/kg) daily for 28 days. After that, donepezil (5 mg/kg) and GLTs (0.4, 0.8, and 1.6 g/kg) were administered orally for 35 days. During the treatment period, aluminum chloride (20 mg/kg) and D-galactose (120 mg/kg) were continuously administered. And the behavior of the animals and the molecular changes of the hippocampus were determined after the whole experimental procedure. Furthermore, BV-2 cells were employed to validate GLTs' anti-neuroinflammatory properties. ResultsThe total triterpenoids content was 443.12 ± 0.21 g/kg and was inferred to contain 19 classes of substances such as organic acids, amino acids, vitamins, flavonoids, and other chemicals in GLTs. Treatment of D-galactose/aluminum chloride-induced mouse with GLTs can ameliorate AD symptoms, counteract cognitive decline, improve Aβ1-42 deposition, reduce the expression level of pro-apoptotic proteins, and attenuate the activation of hippocampal microglia and astrocytes. GLTs significantly increased the expression of antioxidant enzymes and significantly reduced the expression of inflammatory factors. GLTs inhibits nuclear factor kappa B (NF-κB) nuclear translocation and preserves myd88/traf6-mediated mitogen-activated protein kinase (MAPK) phosphorylation. Furthermore, GLTs (2 and 5 mg/mL) inhibited the generation of nitric oxide and protected lipopolysaccharide (1 mg/L)-induced neuroinflammation in BV-2 cells. ConclusionsTaken together, Ganoderma leucocontextum triterpenoids can improve cognitive functions, including learning and memory, by reducing neuroinflammation and oxidative stress, preventing apoptosis, and controlling amyloid genesis.

Anti-Inflammatory Activity of the Combination of Nobiletin and Docosahexaenoic Acid in Lipopolysaccharide-Stimulated RAW 264.7 Cells: A Potential Synergistic Anti-Inflammatory Effect.

This study aimed to investigate a synergistic anti-inflammatory effect of a citrus flavonoid nobiletin and docosahexaenoic acid (DHA), one of n-3 long-chain polyunsaturated fatty acids, in combination. Simultaneous treatment with nobiletin and DHA synergistically inhibited nitric oxide production (combination index < 0.9) by mouse macrophage-like RAW 264.7 cells stimulated with lipopolysaccharide (LPS) without cytotoxicity. On the other hand, the inhibitory effect of nobiletin and DHA in combination on proinflammatory cytokine production was not synergistic. Neither nobiletin nor DHA affected the phagocytotic activity of RAW 264.7 cells stimulated with LPS. Immunoblot analysis revealed that the inhibition potency of DHA on the phosphorylation of ERK and p38 and nuclear translocation of NF-κB is markedly enhanced by simultaneously treating with nobiletin, which may lead to the synergistic anti-inflammatory effect. Overall, our findings show the potential of the synergistic anti-inflammatory effect of nobiletin and DHA in combination.

Dihydromyricetin ameliorates diabetic renal fibrosis via regulating SphK1 to suppress the activation of NF-κB pathway

Dihydromyricetin (DHM) is a flavonoid from vine tea with broad pharmacological benefits, which improve inflammation by blocking the NF-κB pathway. A growing body of research indicates that chronic kidney inflammation is vital to the pathogenesis of diabetic renal fibrosis. Sphingosine kinase-1 (SphK1) is a key regulator of diabetic renal inflammation, which triggers the NF-κB pathway. Hence, we evaluated whether DHM regulates diabetic renal inflammatory fibrosis by acting on SphK1. Here, we demonstrated that DHM effectively suppressed the synthesis of fibrotic and inflammatory adhesion factors like ICAM-1, and VCAM-1 in streptozotocin-treated high-fat diet-induced diabetic mice and HG-induced glomerular mesangial cells (GMCs). Moreover, DHM significantly suppressed NF-κB pathway activation and reduced SphK1 activity and protein expression under diabetic conditions. Mechanistically, the results of molecular docking, molecular dynamics simulation, and cellular thermal shift assay revealed that DHM stably bound to the binding pocket of SphK1, thereby reducing sphingosine-1-phosphate content and SphK1 enzymatic activity, which ultimately inhibited NF-κB DNA binding, transcriptional activity, and nuclear translocation. In conclusion, our data suggested that DHM inhibited SphK1 phosphorylation to prevent NF-κB activation thus ameliorating diabetic renal fibrosis. This supported the clinical use and further drug development of DHM as a potential candidate for treating diabetic renal fibrosis.

Multilevel Regulation of NF-κB Signaling by NSD2 Suppresses Kras-Driven Pancreatic Tumorigenesis.

Pancreatic ductal adenocarcinoma (PDAC) is a clinically challenging cancer with a dismal overall prognosis. NSD2 is an H3K36-specific di-methyltransferase that has been reported to play a crucial role in promoting tumorigenesis. Here, the study demonstrates that NSD2 acts as a putative tumor suppressor in Kras-driven pancreatic tumorigenesis. NSD2 restrains the mice from inflammation and Kras-induced ductal metaplasia, while NSD2 loss facilitates pancreatic tumorigenesis. Mechanistically, NSD2-mediated H3K36me2 promotes the expression of IκBα, which inhibits the phosphorylation of p65 and NF-κB nuclear translocation. More importantly, NSD2 interacts with the DNA binding domain of p65, attenuating NF-κB transcriptional activity. Furthermore, inhibition of NF-κB signaling relieves the symptoms of Nsd2-deficient mice and sensitizes Nsd2-null PDAC to gemcitabine. Clinically, NSD2 expression decreased in PDAC patients and negatively correlated to nuclear p65 expression. Together, the study reveals the important tumor suppressor role of NSD2 and multiple mechanisms by which NSD2 suppresses both p65 phosphorylation and downstream transcriptional activity during pancreatic tumorigenesis. This study opens therapeutic opportunities for PDAC patients with NSD2 low/loss by combined treatment with gemcitabine and NF-κBi.

Polydatin attenuates diabetic renal inflammatory fibrosis via the inhibition of STING pathway

Diabetic nephropathy (DN) is a complication of diabetes and is mainly characterized by renal fibrosis, which could be attributed to chronic kidney inflammation. Stimulator of interferon genes (STING), a linker between immunity and metabolism, could ameliorate various metabolic and inflammatory diseases. However, the regulatory role of STING in DN remains largely unexplored. In this study, knockdown of STING decreased extracellular matrix (ECM), pro-inflammatory, and fibrotic factors in high glucose (HG)-induced glomerular mesangial cells (GMCs), whereas overexpression of STING triggered the inflammatory fibrosis process, suggesting that STING was a potential target for DN. Polydatin (PD) is a glucoside of resveratrol and has been reported to ameliorate DN by inhibiting inflammatory responses. Nevertheless, whether PD improved DN via STING remains unclear. Here, transcriptomic profiling implied that the STING/NF-κB pathway might be an important target for PD. We further found that PD decreased the protein expression of STING, and subsequently suppressed the activation of downstream targets including TBK1 phosphorylation and NF-κB nuclear translocation, and eventually inhibited the production of ECM, pro-inflammatory and fibrotic factors in HG-induced GMCs. Notably, results of molecular docking, molecular dynamic simulations, surface plasmon resonance, cellular thermal shift assay and Co-immunoprecipitation assay indicated that PD directly bound to STING and restored the declined proteasome-mediated degradation of STING induced by HG. In diabetic mice, PD also inhibited the STING pathway and improved the pathological changes of renal inflammatory fibrosis. Our study elucidated the regulatory role of STING in DN, and the novel mechanism of PD treating DN via inhibiting STING expression.

Adropin promotes testicular functions by modulating redox homeostasis in adult mouse.

Adropin is an emerging metabolic hormone that has a role in regulating energy homeostasis. The present study aimed to explore the impact of adropin on redox homeostasis and its possible role in testicular functions in adult mouse testis. Western blot, flow-cytometry, and TUNEL assay were performed to explore the impact of intra-testicular treatment of adropin (0.5 μg/testis) on testicular functions of adult mice. Hormonal assay was done by ELISA. Further, antioxidant enzyme activities were measured. Adropin treatment significantly increased the sperm count and testicular testosterone by increasing the expression of GPR19 and steroidogenic proteins. Also, adropin treatment reduced the oxidative/nitrosative stress by facilitating the translocation of NRF2 and inhibiting NF-κB into the nucleus of germ cells. Enhanced nuclear translocation of NRF2 leads to elevated biosynthesis of antioxidant enzymes, evident by increased HO-1, SOD, and catalase activity that ultimately resulted into declined LPO levels in adropin-treated mice testes. Furthermore, adropin decreased nuclear translocation of NF-κB in germ cells, that resulted into decreased NO production leading to decreased nitrosative stress. Adropin/GPR19 signaling significantly increased its differentiation, proliferation, and survival of germ cells by elevating the expression of PCNA and declining caspase 3, cleaved caspase 3 expression, Bax/Bcl2 ratio, and TUNEL-positive cells. FACS analysis revealed that adropin treatment enhances overall turnover of testicular cells leading to rise in production of advanced germ cells, notably spermatids. The present study indicated that adropin improves testicular steroidogenesis, spermatogenesis via modulating redox potential and could be a promising target for treating testicular dysfunctions.

GRP78 recognizes EV-F 3D protein and activates NF-κB to repress virus replication by interacting with CHUK/IKBKB.

Enteroviruses are the causative agents associated with several human and animal diseases, posing a significant threat to human and animal health. As one of the host immune defense strategies, innate immunity plays a crucial role in defending against invading pathogens, where the host utilizes a variety of mechanisms to inhibit or eliminate the pathogen. Here, we report a new strategy for the host to repress enterovirus replication by the 78 kDa glucose-regulated protein (GRP78), also known as heat shock protein family A member 5 (HSPA5). The GRP78 recognizes the EV-encoded RNA-dependent RNA polymerases (RdRPs) 3D protein and interacts with the nuclear factor kappa B kinase complex (CHUK) and subunit beta gene (IKBKB) to facilitate the phosphorylation and nuclear translocation of NF-κB, which induces the production of inflammatory factors and leads to a broad inhibition of enterovirus replication. These findings demonstrate a new role of GRP78 in regulating host innate immunity in response to viral infection and provide new insights into the mechanism underlying enterovirus replication and NF-κB activation.IMPORTANCEGRP78 is known as a molecular chaperone for protein folding and plays a critical role in maintaining protein folding and participating in cell proliferation, cell survival, apoptosis, and metabolism. However, the functions of GRP78 to participate in enterovirus genome replication and innate immune responses are rarely documented. In this study, we explored the functions of the EV-3D-interacting protein GRP78 and found that GRP78 inhibits enterovirus replication by activating NF-κB through binding to EV-F 3D and interacting with the NF-κB signaling molecules CHUK/IKBKB. This is the first report that GRP78 interacts with CHUK/IKBKB to activate the NF-κB signaling pathway, which leads to the expression of the proinflammatory cytokines and inhibition of enterovirus replication. These results demonstrate a unique mechanism of virus replication regulation by GRP78 and provide insights into the prevention and treatment of viral infections.

Carbon Free Radical (R⋅) Inactivates NF-κB for Radical Capping Therapy.

Inactivating hyperactivated transcription factors can overcome tumor therapy resistance, but their undruggable features limit the development of conventional inhibitors. Here, we report that carbon-centered free radicals (R⋅) can inactivate NF-κB transcription by capping the active sites in both NF-κB and DNA. We construct a type of thermosensitive R⋅ initiator loaded amphiphilic nano-micelles to facilitate intracellular delivery of R⋅. At a temperature of 43 °C, the generated R⋅ engage in electrophilic radical addition towards double bonds in nucleotide bases, and simultaneously cap the sulfhydryl residues in NF-κB through radical chain reaction. As a result, both NF-κB nuclear translocation and NF-κB-DNA binding are suppressed, leading to a remarkable NF-κB inhibition of up to 94.1 %. We have further applied R⋅ micelles in a clinical radiofrequency ablation tumor therapy model, showing remarkable NF-κB inactivation and consequently tumor metastasis inhibition. Radical capping strategy not only provides a method to solve the heat-sink effect in clinic tumor hyperthermia, but also suggests a new perspective for controllable modification of biomacromolecules in cancer therapy.

Dysregulated NUB1 and Neddylation Enhances Rheumatoid Arthritis Fibroblast-Like Synoviocyte Inflammatory Responses.

Fibroblast-like synoviocytes (FLS) contribute to the pathogenesis of rheumatoid arthritis (RA), in part due to activation of the proinflammatory transcription factor NF-κB. Neddylation is modulated by the negative regulator of ubiquitin-like protein (NUB) 1. We determined whether NUB1 and neddylation are aberrant in the models with RA FLS, thereby contributing to their aggressive phenotype. Models with RA or osteoarthritis (OA) FLS were obtained from arthroplasty synovia. Real-time quantitative polymerase chain reaction and Western blot analysis assessed gene and protein expression, respectively. NUB1 was overexpressed using an expression vector. NF-κB activation was assessed by stimulating FLS with interleukin (IL)-1β. Neddylation inhibitor (MLN4924) and proteasome inhibitor were used in migration and gene expression assays. MLN4924 was used in the model with K/BxN serum-transfer arthritis. Enhanced H3K27ac and H3K27me3 peaks were observed in the NUB1 promoter in the OA FLS compared with the RA FLS. NUB1 was constitutively expressed by FLS, but induction by IL-1β was significantly greater in the OA FLS. The ratio of neddylated cullin (CUL) 1 to nonneddylated CUL1 was lower in the OA FLS than the RA FLS. NUB1 overexpression decreased NF-κB nuclear translocation and IL-6 messenger RNA (mRNA) in IL-1β-stimulated the RA FLS. MLN4924 decreased CUL1 neddylation, NF-κB nuclear translocation, and IL-6 mRNA in IL-1β-stimulated the RA FLS. MLN4924 significantly decreased arthritis severity in the model with K/BxN serum-transfer arthritis. CUL1 neddylation and NUB1 induction is dysregulated in the models with RA, which increases FLS activation. Inhibition of neddylation is an effective therapy in an animal model of arthritis. These data suggest that the neddylation system contributes to the pathogenesis of RA and that regulation of neddylation could be a novel therapeutic approach.

Protective Effects of Bioactive Compound-Derived Nanoparticle Against Diabetic Retinopathy Through the Modulation of the NF-κB Signaling Pathway.

Diabetic retinopathy is a prevalent and severe microvascular complication of diabetes, often causing visual impairment and blindness in adults. This condition significantly impacts the quality of life for many diabetes patients worldwide. Berberine (BBR), a bioactive compound known for its effects on blood glucose levels, has shown promise in managing diabetic complications. However, the exact mechanism of how BBR influences the development of diabetic retinopathy remains unclear. In this study, we focused on synthesizing a formulation derived from BBR and assessing its protective effects against diabetic retinopathy. The formulation was created using a green synthesis method and thoroughly characterized. In vitro studies demonstrated the antioxidant activity of the formulation against 2,2-diphenyl-1-picryl-hydrazyl-hydrate. We also examined the NF-κB signaling pathway at a molecular level using real-time polymerase chain reaction. To mimic diabetic retinopathy in a controlled setting, a diabetic rat model was established through streptozotocin injection. The rats were divided into normal, diabetic, and treatment groups. The treatment group received the formulated treatment via intragastric administration for several weeks, while the other groups received normal saline. Evaluation of histopathological characteristics and microstructural changes in the retina using hematoxylin and eosin staining revealed that the bioactive compound-derived nanoparticle exhibited favorable biological, chemical, and physical properties. Treatment with the formulation effectively reduced oxidative stress induced by diabetes and inhibited the NF-κB signaling pathway in the diabetic rat model. Under high glucose conditions, oxidative stress was heightened, leading to mitochondria-dependent cell apoptosis in Müller cells via the activation of the NF-κB signaling pathway. The bioactive compound-derived formulation counteracted these effects by decreasing IκB phosphorylation, preventing NF-κB nuclear translocation, and deactivating the NF-κB signaling pathway. Furthermore, treatment with the bioactive compound-derived formulation mitigated retinal micro- and ultrastructural changes associated with diabetic retinopathy. These results indicate that the formulation protects against diabetic retinopathy by suppressing oxidative stress, reducing cell apoptosis, and deactivating the NF-κB signaling pathway. This suggests that the bioactive compound-derived formulation could be a promising therapeutic option for diabetic retinopathy.

Mechanisms of vascular inflammaging: TNF-alpha mediates endothelial CEACAM1 expression by NF-KB and beta-Catenin in a biphasic manner

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): German Research Foundation Introduction Chronic inflammation with progressive age, also called inflammaging, is a hallmark of the pathogenesis of cardiovascular diseases. Previously we have shown increased expression of the Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) with progressive age in the vasculature of mice and humans that leads to a chronic pro-inflammatory milieu via mutual upregulation with TNF-α. Furthermore, CEACAM1 critically promotes vascular aging processes like collagen deposition, endothelial permeability as well as enhanced oxidative stress. Therefore, CEACAM1 is a main mediator of vascular inflammaging that may facilitate progress into cardiovascular diseases. In this study we identified the mechanisms that underly the upregulation of endothelial CEACAM1 expression by TNF-α in detail. Methods Wildtype (WT) and TNF-α knockout (Tnf-/-) mice of different age were used to determine the impact of TNF-α on age-dependent CEACAM1 expression in vivo. Underlying mechanisms of TNF-α-dependent CEACAM1 upregulation were further analyzed in an endothelial cell culture model using pharmacological inhibition and siRNA-mediated knockdown of signaling pathways. Activation of signaling pathways was confirmed by determining the phosphorylation status of signaling components via Western Blot and analysis of nuclear translocation of NF-κB and β-Catenin using subcellular fractionation. Results Immunohistochemical analyses of aortic sections from WT and Tnf-/- mice of different age reveal that TNF-α critically contributes to the aging-related upregulation of endothelial CEACAM1 expression in vivo. Mechanistic analyses in vitro showed that TNF-α upregulated CEACAM1 expression in a time-dependent manner. In pharmacological experiments we identified an early NF-κB- and a delayed β-Catenin-mediated response. This finding was supported by time-matched nuclear translocation of NF-κB and β-Catenin. Furthermore, siRNA-mediated knockdown of the β-Catenin-targeted transcription factor TCF4 reduced TNF-α-mediated CEACAM1 upregulation. Co-immunoprecipitation analyses show that β-Catenin is released by TNF-α-mediated adherens junctions disassembly. Furthermore, TNF-α enhanced activating phosphorylation of Akt kinase at Ser473. Akt kinase in turn increased phosphorylation of β-Catenin at Ser552, a modification reported to augment its transcriptional activity. Additionally, Akt kinase facilitated β-Catenin signaling by inhibition of its degradation via phosphorylation of GSK3β at Ser9. Conclusion Taken together, this study identified the signaling mechanisms that underly the vascular upregulation of CEACAM1 with age. Our results directly link endothelial barrier impairment, an initial step in the pathogenesis of atherosclerosis, to CEACAM1 expression. Since CEACAM1 critically promotes vascular inflammaging and age-dependent vascular alterations this further emphasizes the potential of CEACAM1 as a novel target to prevent cardiovascular diseases.

Daidzein alleviates isoproterenol-induced cardiac injury in rats via NF-kB pathway inhibition

The current study set out to explore the anti-inflammatory effects of Daidzein (Dz) on the isoproterenol (Iso)-induced myocardial infarction (MI) in male Wistar rats. Iso(80 mg/kg) was injected subcutaneously into rats to cause MI for two days at intervals of 24 hours. ELISA kits were used to measure the amounts of TNF-α &amp; IL-6 in cardiac tissues. The quantity of NF-kB in the cytosol and nuclei was measured using a western blot approach. H&amp;E staining was used to identify histological cardiac changes. In rats with Iso-induced myocardial infarction, Dz therapy shrunk the size of the infarct and reduced histological anomalies in the myocardium. Dz significantly lowered cardiac pro-inflammatory cytokine levels and prevented NF-kB nuclear translocation in MI-damaged rats, substantially reversing Iso-induced damage. This research shows that daidzein treatment in vivo reduces Iso-induced myocardial damage by preventing NF-kB activation, which may therefore reduce the release of inflammatory cytokines.

Locusta migratoria hydrolysates attenuate lipopolysaccharide (LPS)/D-Galactosamine (D-Gal)-induced cytotoxicity and inflammation in Hep G2 cells via NF-κB signaling suppression

The prolonged state of hepatic inflammation can lead to liver damage, a critical driving force in the progression of liver-related diseases. Locusta migratoria (LM), an edible insect, is recognized for its protein richness and potential to produce a range of bioactive polypeptides, presenting a novel solution for liver disease. This study investigated the hepatoprotective effects of LM hydrolysates in human hepatoma G2 (Hep G2) cells challenged with lipopolysaccharide (LPS)/D-Galactosamine (D-Gal), a model of liver injury. Remarkably, LM hydrolysates significantly ameliorated cell damage, as evidenced by the inhibition of the LPS/D-Gal-induced decrease in cell viability and reduction in lactate dehydrogenase (LDH) release. Furthermore, LM hydrolysates alleviated the release of aspartate aminotransferase (AST) from cells exposed to LPS/D-Gal and lowered the secretion of inflammatory cytokines while suppressing the activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), a key pathway in inflammation. In particular, LM-N hydrolysate mitigated hepatotoxicity by attenuation of inflammatory responses to reduce interleukin 6 (IL-6) levels, and NF-κB nuclear translocation. These findings suggest that LM hydrolysates could potentially offer hepatoprotective effects by mitigating the inflammatory responses induced by LPS/D-Gal.