NF-κB Inhibitor Research Articles

IκBε deficiency accelerates disease development in chronic lymphocytic leukemia.

The NFKBIE gene, which encodes the NF-κB inhibitor IκBε, is mutated in 3-7% of patients with chronic lymphocytic leukemia (CLL). The most recurrent alteration is a 4-bp frameshift deletion associated with NF-κB activation in leukemic B cells and poor clinical outcome. To study the functional consequences of NFKBIE gene inactivation, both in vitro and in vivo, we engineered CLL B cells and CLL-prone mice to stably down-regulate NFKBIE expression and investigated its role in controlling NF-κB activity and disease expansion. We found that IκBε loss leads to NF-κB pathway activation and promotes both migration and proliferation of CLL cells in a dose-dependent manner. Importantly, NFKBIE inactivation was sufficient to induce a more rapid expansion of the CLL clone in lymphoid organs and contributed to the development of an aggressive disease with a shortened survival in both xenografts and genetically modified mice. IκBε deficiency was associated with an alteration of the MAPK pathway, also confirmed by RNA-sequencing in NFKBIE-mutated patient samples, and resistance to the BTK inhibitor ibrutinib. In summary, our work underscores the multimodal relevance of the NF-κB pathway in CLL and paves the way to translate these findings into novel therapeutic options.

Tobacco smoke condensate-induced senescence in endothelial cells was ameliorated by colchicine treatment via suppression of NF-κB and MAPKs P38 and ERK pathways activation

Smoking is the major cause of cardiovascular diseases and cancer. It induces oxidative stress, leading to DNA damage and cellular senescence. Senescent cells increase the expression and release of pro-inflammatory molecules and matrix metalloproteinase, which are known to play a vital role in the initiation and progression of cardiovascular diseases and metastasis in cancer. The current study investigated the smoking induced cellular senescence and employed colchicine that blocked senescence in endothelial cells exposed to tobacco smoke condensate. Colchicine prevented oxidative stress and DNA damage in tobacco smoke-condensate-treated endothelial cells. Colchicin reduced β-gal activity, improved Lamin B1, and attenuated cell growth arrest markers P21 and P53. Colchicine also ameliorated the expression of SASP factors and inhibited the activation of NF-kB and MAPKs P38 and ERK. In summary, colchicine inhibited tobacco smoke condensate-induced senescence in endothelial cells by blocking the activation of NF-kB and MAPKs P38 and ERK.Graphical

Equisetum arvense standardized dried extract hinders age-related osteosarcopenia

Age-associated osteosarcopenia is an unresolved syndrome characterized by the concomitant loss of bone (osteopenia) and skeletal muscle (sarcopenia) tissues increasing falls, immobility, morbidity, and mortality. Unbalanced resorption of bone in the remodeling process and excessive protein breakdown, especially fast type II myosin heavy chain (MyHC-II) isoform and myofiber metabolic shift, are the leading causes of bone and muscle deterioration in the elderly, respectively. Equisetum arvense (EQ) is a plant traditionally recommended for many pathological conditions due to its anti-inflammatory properties. Thus, considering that a chronic low-grade inflammatory state predisposes to both osteoporosis and sarcopenia, we tested a standardized hydroalcoholic extract of EQ in in vitro models of muscle atrophy [C2C12 myotubes treated with proinflammatory cytokines (TNFα/IFNγ), excess glucocorticoids (dexamethasone), or the osteokine, receptor activator of nuclear factor kappa-B ligand (RANKL)] and osteoclastogenesis (RAW 264.7 cells treated with RANKL). We found that EQ counteracted myotube atrophy, blunting the activity of several pathways depending on the applied stimulus, and reduced osteoclast formation and activity. By in silico target fishing, IKKB-dependent nuclear factor kappa-B (NF-κB) inhibition emerges as a potential common mechanism underlying EQ′s anti-atrophic effects. Consumption of EQ (500 mg/kg/day) by pre-geriatric C57BL/6 mice for 3 months translated into: i) maintenance of muscle mass and performance; ii) restrained myofiber oxidative shift; iii) slowed down age-related modifications in osteoporotic bone, significantly preserving trabecular connectivity density; iv) reduced muscle- and spleen-related inflammation. EQ can preserve muscle functionality and bone remodeling during aging, potentially valuable as a natural treatment for osteosarcopenia.

TAK1-binding protein 2 (TAB2) and TAB3 are redundantly required for TLR-induced cytokine production in macrophages.

Transforming growth factor-β-activated kinase 1 (TAK1) plays a pivotal role in innate and adaptive immunity. TAK1 is essential for the activation of mitogen-activated protein kinases (MAPKs) and nuclear factor (NF)-κB pathways downstream of diverse immune receptors, including toll-like receptors (TLRs). Upon stimulation with TLR ligands, TAK1 is activated via recruitment to the lysine 63-linked polyubiquitin chain through TAK1-binding protein 2 (TAB2) and TAB3. However, the physiological importance of TAB2 and TAB3 in macrophages is still controversial. A previous study has shown that mouse bone marrow-derived macrophages (BMDMs) isolated from mice double deficient for TAB2 and TAB3 produced tumor necrosis factor (TNF)-α and interleukin (IL)-6 to the similar levels as control wild-type BMDMs in response to TLR ligands such as lipopolysaccharide (LPS) or Pam3CSK4, indicating that TAB2 and TAB3 are dispensable for TLR signaling. In this study, we revisited the role of TAB2 and TAB3 using an improved mouse model. We observed a significant impairment in the production of pro-inflammatory cytokines and chemokine in LPS- or Pam3CSK4-treated BMDMs deficient for both TAB2 and TAB3. Double deficiency of TAB2 and TAB3 resulted in the decreased activation of NF-κB and MAPK pathways as well as the slight decrease in TAK1 activation in response to LPS or Pam3CSK4. Notably, the TLR-mediated expression of inhibitor of NF-κB (IκB)ζ was severely compromised at the protein and messenger RNA (mRNA) levels in the TAB2/TAB3 double-deficient BMDMs, thereby impeding IL-6 production. Our results suggest that TAB2 and TAB3 play a redundant and indispensable role in the TLR signaling pathway.

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

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

Pivotal role of dihydroorotate dehydrogenase as a therapeutic target in adult T-cell leukemia.

We aimed to determine the role of dihydroorotate dehydrogenase (DHODH) in pathogenesis of adult T-cell leukemia (ATL) caused by human T-cell leukemia virus type 1 (HTLV-1) and the effects of its inhibition on the de novo pyrimidine biosynthesis pathway. Cell proliferation, viability, cycle, and apoptosis were analyzed using WST-8 assays, flow cytometry, and Hoechst 33342 staining. To elucidate the molecular mechanisms involved in the anti-ATL effects of DHODH knockdown and inhibition, RT-PCR and immunoblotting were conducted. HTLV-1-infected T-cell lines aberrantly expressed DHODH. Viral infection and the oncoprotein, Tax, enhanced DHODH expression, while knockdown of DHODH decreased HTLV-1-infected T-cell growth. In addition, BAY2402234, a DHODH inhibitor, exerted an anti-proliferative effect, which was reversed by uridine supplementation. BAY2402234 induced DNA damage and S phase arrest by downregulating c-Myc, CDK2, and cyclin A and upregulating p53 and cyclin E. It also induced caspase-mediated apoptosis by the upregulation of pro-apoptotic and downregulation of anti-apoptotic proteins. Furthermore, BAY2402234 induced caspase-independent ferroptosis and necroptosis. It decreased phosphorylation of IKK, IκBα, PTEN, Akt, and its downstream targets, suggesting that inhibition of NF-κB and Akt signaling is involved in its anti-ATL action. These findings highlight DHODH as a potential therapeutic target for treating ATL.

Bortezomib suppresses acute myelogenous leukaemia stem-like KG-1a cells via NF-κB inhibition and the induction of oxidative stress.

Acute myelogenous leukaemia (AML) originates and is maintained by leukaemic stem cells (LSCs) that are inherently resistant to antiproliferative therapies, indicating that a critical strategy for overcoming chemoresistance in AML therapy is to eradicate LSCs. In this work, we investigated the anti-AML activity of bortezomib (BTZ), emphasizing its anti-LSC potential, using KG-1a cells, an AML cell line with stem-like properties. BTZ presented potent cytotoxicity to both solid and haematological malignancy cells and reduced the stem-like features of KG-1a cells, as observed by the reduction in CD34- and CD123-positive cells. A reduction in NF-κB p65 nuclear staining was observed in BTZ-treated KG-1a cells, in addition to upregulation of the NF-κB inhibitor gene NFΚBIB. BTZ-induced DNA fragmentation, nuclear condensation, cell shrinkage and loss of transmembrane mitochondrial potential along with an increase in active caspase-3 and cleaved PARP-(Asp 214) level in KG-1a cells. Furthermore, BTZ-induced cell death was partially prevented by pretreatment with the pancaspase inhibitor Z-VAD-(OMe)-FMK, indicating that BTZ induces caspase-mediated apoptosis. BTZ also increased mitochondrial superoxide levels in KG-1a cells, and BTZ-induced apoptosis was partially prevented by pretreatment with the antioxidant N-acetylcysteine, indicating that BTZ induces oxidative stress-mediated apoptosis in KG-1a cells. At a dosage of 0.1 mg/kg every other day for 2 weeks, BTZ significantly reduced the percentage of hCD45-positive cells in the bone marrow and peripheral blood of NSG mice engrafted with KG-1a cells with tolerable toxicity. Taken together, these data indicate that the anti-LSC potential of BTZ appears to be an important strategy for AML treatment.

Effects of epimedium total flavone capsules on post-stroke cognitive impairment in rats

To investigate the effect of epimedium total flavone capsules on post-stroke cognitive impairment(PSCI) in rats. The transient middle cerebral artery occlusion(tMCAO) model was constructed on selected rats, and rats with impaired neurological function were randomly divided into the model group, low, middle, and high dose groups of epimedium total flavone capsules, and nimodipine tablet group. The cognitive function of rats was measured after administration. Pathological changes in brain tissue were observed after hematoxylin-eosin staining(HE). Neuronal nuclei(NeuN) and glial fibrillary acidic protein(GFAP) distribution in brain tissue were tested by immunofluorescent staining. The level of amyloid beta 1-42(Aβ_(1-42)), neuron specific enolase(NSE), acetylcholine(ACH), dopamine(DA), 5-hydroxytryptamine(5-HT), norepinephrine(NE), interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α), and hypersensitive C-reactive protein(hs-CRP) in rat serum was tested. Moreover, Western blot was utilized to test the expression of nuclear factor-kappaB(NF-κB), p-NF-κB, alpha inhibitor of NF-κB(IκBα) protein, and p-IκBα protein in the hippocampus. The experimental results showed that epimedium total flavone capsules can improve the cognitive function of model rats, and the mechanism may be related to the regulation of the expression of p-IκBα and p-NF-κB proteins, so as to inhibit inflammatory response induced by ischemia-reperfusion.

296 Towards Nose-to-brain Inhibition of NFB: Activity of a Novel p65 Inhibitor in Glioblastoma and Feasibility of Intranasal Delivery With a Near-infrared Fluorescent HMC-Chitosan Nanoparticle

INTRODUCTION: Constitutive NFκB inflammatory signaling is a driving force of tumor progression, immune evasion, and therapeutic resistance in glioblastoma (GBM). CRL1101 is a novel small molecule inhibitor of RelA (p65), a transcription factor of NFκB-mediated gene expression. Previously, we have shown that heptamethine carbocyanine (HMC) conjugated nanoparticles target GBM tumor sites via organic anion transporter proteins. The activity of CRL1101 in GBM has not been explored. Poor blood-brain barrier (BBB) penetration and theoretical toxicities related to p65 inhibition pose challenges to its implementation in vivo. METHODS: GBM transcriptomic analysis was performed using Gene Profiling Interactive Analysis. In vitro cytotoxicity and migration assays were performed in U87 and GL261. Western blot was used to confirm the mechanism of CRL1101. Quantitative PCR was used to assess the relative expression of NFκB-regulated genes. HMC-chitosan-CRL1101 nanoparticles were synthesized by cross-linking chitosan with HMC and their uptake was visualized using immunocytochemistry. For survival analysis, we implanted GL261 cells into immunocompetent mice and treated intranasally with HMC-chitosan-CRL1101. RESULTS: RelA is overexpressed in GBM relative to normal brain tissue. CRL1101 alone effectively kills U87 cells (IC50 = 16.0 uM) and prevents migration in vitro (p < 0.0001) by disabling the nuclear translocation of RelA. Treatment with CRL1101 was associated with a decrease in IL-8 (p = 0.01) and PD-L1 (p = 0.44) expression. HMC-chitosan-CRL1101 demonstrated an IC50 of 25.23 uM in U87. Near-infrared imaging confirmed intranasal delivery of HMC-chitosan-CRL1101 across the BBB in vivo. CONCLUSIONS: RelA-targeted NFκB inhibition with CRL1101 is a promising immunotherapeutic strategy in GBM. Intranasal nanoparticle delivery is a practical route to bypass the BBB and minimize systemic toxicities in mouse models of GBM, with expected survival benefit in vivo.

A Nuphar lutea plant active ingredient, 6,6′-dihydroxythiobinupharidine, ameliorates kidney damage and inflammation in a mouse model of chronic kidney disease

Chronic Kidney Disease (CKD) associated complications are associated with increased inflammation through the innate immune response, which can be modulated with anti-inflammatory agents. An active ingredient derived from the Nuphar lutea aquatic plant, 6,6′-dihydroxythiobinupharidine (DTBN) has anti-inflammatory properties, mainly through the inhibition of NF-κB. We tested the effects of DTBN on mice with CKD. After preliminary safety and dosing experiments, we exposed 8 weeks old male C57BL/6J mice to adenine diet to induce CKD. Control and CKD animals were treated with IP injections of DTBN (25 μg QOD) or saline and sacrificed after 8 weeks. Serum urea and creatinine were significantly decreased in CKD-DTBN Vs CKD mice. Kidney histology showed a decrease in F4/80 positive macrophage infiltration, damaged renal area, as well as decreased kidney TGF-β in CKD-DTBN Vs CKD mice. Kidney inflammation indices (IL-1β, IL-6 and P-STAT3) were significantly decreased in CKD-DTBN as compared to CKD mice. DTBN treatment showed no apparent damage to tissues in control mice, besides a decrease in weight gain and mild hypoalbuminemia without proteinuria. Thus, DTBN significantly improved renal failure and inflammation indices in CKD mice. Therefore, this and similar substances may be considered as an additional treatment in CKD patients.

Loranthus tanakae Franch. and Sav. Attenuates Respiratory Inflammation Caused by Asian Sand Dust.

Asian sand dust (ASD), generally produced in East Asia, including China, Japan, and Korea, directly leads to the development of pulmonary disease and exacerbates underlying pulmonary diseases. Loranthus tanakae Franch. and Sav. is a traditional herbal medicine applied to improve various inflammatory conditions. Here, we evaluated the curative properties of L. tanakae ethanol extract (LTE) against pulmonary inflammation caused by ASD. Additionally, to investigate the mechanism of action of LTE, we performed network pharmacological analysis. ASD was administrated on day 1, 3, and 5 by intranasal instillation, and LTE was orally administered for 6 days. Administration of LTE significantly decreased inflammatory cytokines and the number of inflammatory cells in bronchoalveolar lavage fluid, which was accompanied by a decrease in inflammatory cell accumulation in pulmonary tissue. Administration of LTE decreased the expression of cyclooxygenase2 and matrix metalloproteinase-9 in mice exposed to ASD with the decline in p65 phosphorylation. Additionally, administration of LTE significantly elevated hemeoxygenase (HO)-1 expression in the pulmonary tissue of mice exposed to ASD. These results were consistent with the data of network pharmacological analysis. This experiment showed that LTE attenuated pulmonary inflammation caused by ASD via inhibition of NF-κB and elevation of HO-1. Therefore, LTE may have potential as a therapeutic agent to treat pulmonary inflammation caused by ASD.

Immunomodulatory Effects of Fluoroquinolones in Community-Acquired Pneumonia-Associated Acute Respiratory Distress Syndrome.

Community-acquired pneumonia is reported as one of the infectious diseases that leads to the development of acute respiratory distress syndrome. The innate immune system is the first line of defence against microbial invasion; however, its dysregulation during infection, resulting in an increased pathogen load, stimulates the over-secretion of chemokines and pro-inflammatory cytokines. This phenomenon causes damage to the epithelial-endothelial barrier of the pulmonary alveoli and the leakage of the intravascular protein into the alveolar lumen. Fluoroquinolones are synthetic antimicrobial agents with immunomodulatory properties that can inhibit bacterial proliferation as well as exhibit anti-inflammatory activities. It has been demonstrated that the structure of fluoroquinolones, particularly those with a cyclopropyl group, exerts immunomodulatory effects. Its capability to inhibit phosphodiesterase activity leads to the accumulation of intracellular cAMP, which subsequently enhances PKA activity, resulting in the inhibition of transcriptional factor NF-κB and the activation of CREB. Another mechanism reported is the inhibition of TLR and ERK signalling pathways. Although the sequence of events has not been completely understood, significant progress has been made in comprehending the specific mechanisms underlying the immunomodulatory effects of fluoroquinolones. Here, we review the indirect immunomodulatory effects of FQs as an alternative to empirical therapy in patients diagnosed with community-acquired pneumonia.

Inhibition of NF-κB and ERK signaling pathways in osteoclasts and M1 macrophage polarization: Mechanistic insights into the anti-osteoporotic effects of Pseudolaric acid B

Osteoporosis, characterized by bone metabolism disruption leading to gradual bone loss and increased fracture susceptibility, is linked to the excessive activation of osteoclasts. Pseudolaric acid B (PAB), identified as an NF-κB signaling inhibitor crucial for osteoclastogenesis, is explored here for its protective effects in osteoporosis. Noncytotoxic PAB's impact on osteoclast differentiation was assessed through cell viability and osteoclast formation assays, with subsequent testing of osteoclast function via bone resorption assays. Quantitative real-time polymerase chain reaction evaluated PAB's genetic-level impact on osteoclastogenesis. Network pharmacology, western blot, and luciferase reporter gene assays were employed to elucidate PAB's regulatory mechanism. In an in vivo model of osteoporosis induced by ovariectomy (OVX) in mice, micro-CT, H&E staining, and TRAP staining facilitated histomorphometry analysis, while flow cytometry verified macrophage polarization. PAB demonstrated inhibitory effects on osteoclast formation and bone resorption in BMM and RAW264.7 cells, suppressing osteoclast-specific genes. Bioinformatic analysis, western blot, and luciferase assay results indicated PAB's inhibition of IκBα phosphorylation in the NF-κB signaling pathway and ERK in MAPKs, elucidating its mechanism. In vivo experiments confirmed PAB's attenuation of osteoporosis by reducing osteoclast formation in OVX mice. PAB further facilitated macrophage conversion from M1 to M2 and suppressed IL-1β, TNF-α, and IL-6 synthesis. In conclusion, PAB prevents osteoporosis by inhibiting RANKL-induced osteoclastogenesis through NF-κB and ERK signaling pathway suppression, coupled with macrophage polarization. These findings indicate the potential therapeutic role of PAB in osteoporosis.

Piperine alleviates nonalcoholic steatohepatitis by inhibiting NF-κB-mediated hepatocyte pyroptosis.

Nonalcoholic steatohepatitis (NASH) is the progressive form of nonalcoholic fatty liver disease (NAFLD), which has a high risk of cirrhosis, liver failure, and hepatocellular carcinoma. Piperine (Pip) is an extract of plants with powerful anti-inflammatory effects, however, the function of Pip in NASH remains elusive. Here, we aim to explore the role of Pip in NASH and to find the possible mechanisms. Methionine and choline-deficient (MCD) diets were used to induce steatohepatitis, methionine- and choline-sufficient (MCS) diets were used as the control. After Pip treatment, H&E staining, Oil Red O staining, hepatic triglyceride (TG) content and F4/80 expression were performed to analysis liver steatosis and inflammation; Masson's staining, COL1A1 and α-SMA were detected liver fibrosis. Lipopolysaccharide (LPS) -treated AML12 cells were used to as the cell model to induce pyroptosis. Then, pyroptosis-related proteins, IL-1β and LDH release were detected in vivo and in vitro. Finally, NF-κB inhibitor, BAY11-7082, was used to further demonstrate the mechanism of Pip in NASH. The study found that Pip alleviated liver steatosis, inflammation, hepatocyte injury, and fibrosis in mice fed with MCD diets. Moreover, the pyroptosis markers (NLRP3, ASC, caspase-1 p20, and GSDMD), IL-1β and LDH release were decreased by Pip treatment. NF-κB activation was suppressed by Pip treatment and pyroptosis-related proteins were down regulated by BAY11-7082. Pip ameliorates NASH progression, and the therapeutical effect was associated with inhibition of hepatocyte pyroptosis induced by NF-κB.

MG53 protects against Coxsackievirus B3-induced acute viral myocarditis in mice by inhibiting NLRP3 inflammasome-mediated pyroptosis via the NF-κB signaling pathway

Pyroptosis, a novel programmed cell death mediated by NOD-like receptor protein 3 (NLRP3) inflammasome, is a critical pathogenic process in acute viral myocarditis (AVMC). Mitsugumin 53 (MG53) is predominantly expressed in myocardial tissues and has been reported to exert cardioprotective effects through multiple pathways. Herein, we aimed to investigate the biological function of MG53 in AVMC and its underlying regulatory mechanism in pyroptosis. BALB/c mice and HL-1 cells were infected with Coxsackievirus B3 (CVB3) to establish animal and cellular models of AVMC. As inflammation progressed in the myocardium, we found a progressive decrease in myocardial MG53 expression, accompanied by a significant enhancement of cardiomyocyte pyroptosis. MG53 overexpression significantly alleviated myocardial inflammation, apoptosis, fibrosis, and mitochondrial damage, thereby improving cardiac dysfunction in AVMC mice. Moreover, MG53 overexpression inhibited NLRP3 inflammasome-mediated pyroptosis, reduced pro-inflammatory cytokines (IL-1β/18) release, and suppressed NF-κB signaling pathway activation both in vivo and in vitro. Conversely, MG53 knockdown reduced cell viability, facilitated cell pyroptosis, and increased pro-inflammatory cytokines release in CVB3-infected HL-1 cells by promoting NF-κB activation. These effects were partially reversed by applying the NF-κB inhibitor BAY 11–7082. In conclusion, our results suggest that MG53 acts as a negative regulator of NLRP3 inflammasome-mediated pyroptosis in CVB3-induced AVMC, partially by inhibiting the NF-κB signaling pathway. MG53 is a promising candidate for clinical applications in AVMC treatment.

Geraniin Alleviates Inflammation in Caco-2 Cells and Dextran Sulfate Sodium-Induced Colitis Mice by Targeting IL-1β.

IL-1β is an important cytokine implicated in the progression of inflammatory bowel disease (IBD) and intestinal barrier dysfunction. The polyphenolic compound, geraniin, possesses bioactive properties, such as antitumor, antioxidant, anti-inflammatory, antihypertensive, and antiviral activities; however, its IL-1β-targeted anticolitis activity remains unclear. Here, we evaluated the inhibitory effect of geraniin in IL-1β-stimulated Caco-2 cells and a dextran sulfate sodium (DSS)-induced colitis mouse model. Geraniin blocked the interaction between IL-1β and IL-1R by directly binding to IL-1β and inhibited the IL-1β activity. It suppressed IL-1β-induced intestinal tight junction damage in human Caco-2 cells by inhibiting IL-1β-mediated MAPK, NF-kB, and MLC activation. Moreover, geraniin administration effectively reduced colitis symptoms and attenuated intestinal barrier injury in mice by suppressing elevated intestinal permeability and restoring tight junction protein expression through the inhibition of MAPK, NF-kB, and MLC activation. Thus, geraniin exhibits anti-IL-1β activity and anticolitis effect by hindering the IL-1β and IL-1R interaction and may be a promising therapeutic anti-IL-1β agent for IBD treatment.

Abstract 3787: Important role of GPX1 and NF-kb signaling pathway in human gastric cancer including cell proliferation and invasion

Abstract Background: Glutathione peroxidases(GPXs) are member of an antioxidant enzyme family. Their role is to eliminate the reactive oxygen species(ROS). Many available studies confirm that over expression of GPXs can promote cancer cell proliferation and invasion. Among the 8 GPXs, Glutathione peroxidase-1 (GPX1) is the most plentiful. Overexpression of GPX1 has been noted to promote invasion, migration, cisplatin resistance and proliferation in breast, colorectal and lung cancer. NF-kB is a ubiquitous nuclear transcription factor in the human body. that key role in cell proliferation, apoptosis and tumor progression. In reliable studies, inhibition of NF-kB expression has been shown to reduce the malignancy of Esophageal squamous cell carcinoma. Accordingly, the purpose of this study is to identify the GPX1 and NF-kB signaling pathway and their correlation with cancer cell proliferation and invasion in vitro using gastric cancer cell. Methods: In our study, we used cell culture, Northern blotting, cDNA microarray analysis, western blotting, RT-PCR, Zymography, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay, GPX1 knock-down with short hairpin RNS(shRNA), Standard two-chamber invasion assay, Chromatin immunoprecipitation assay. Results: First, we confirmed that the expression level of GPX1 was up-regulated by HGF(hepatocyte growth factor) in gastric cancer cells. The cells were treated with NF-kB inhibitor, Pyrrolidine dithiocarbamate(PDTC), and analyzed by Western blotting to identify the associated pathway of HGF-induced GPX1 with NF-kB. The HGF-induced GPX1 protein level was down regulated by PDTC. The role of GPX1 associated with NF-kB was determined by knock down GPX1 expression using GPX1-sh RNA. The GPX1-sh RNA treated cells showedvdown regulation of NF-kB and urokinase Plasminogen activator(uPA) also. To fine the upper regulator of GPX1 signaling pathway, we treated AKT inhibitor(LY294002) ant then analyzed by Western blotting to identify associated pathway of HGF-induced GPX1 with AKT. When AKT pathway was inhibited, GPX1 and NF-kB were down-regulated in gastric cancer cell. HGF-mediated cell proliferation and invasion in vitro was decreased in GPX1 knock down cell. We identified the putative binding site of GPX1 promotor containing NF-kB binding site and confirmed the function by CHIP assay. Conclusions: This study aimed to investigate relationship between GPX1 and NF-kB in gastric cancer cells. Results showed that HGF induced GPX1 expression through the NF-kB and AKT pathway and GPX1 may play a significant role in cell proliferation and invasion in gastric cancer. Therefore, GPX1 can be a potential therapeutic target of gastric cancer for the treatment. Citation Format: Byeong Il Jang, Ji Yoon Jung, Sung Ae Koh, Kyung Hee Lee. Important role of GPX1 and NF-kb signaling pathway in human gastric cancer including cell proliferation and invasion [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3787.

Serum Induces the Subunit-Specific Activation of NF-κB in Proliferating Human Cardiac Stem Cells.

Cardiovascular diseases (CVDs) are often linked to ageing and are the major cause of death worldwide. The declined proliferation of adult stem cells in the heart often impedes its regenerative potential. Thus, an investigation of the proliferative potential of adult human cardiac stem cells (hCSCs) might be of great interest for improving cell-based treatments of cardiovascular diseases. The application of human blood serum was already shown to enhance hCSC proliferation and reduce senescence. Here, the underlying signalling pathways of serum-mediated hCSC proliferation were studied. We are the first to demonstrate the involvement of the transcription factor NF-κB in the serum-mediated proliferative response of hCSCs by utilizing the NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC). RNA-Sequencing (RNA-Seq) revealed ATF6B, COX5B, and TNFRSF14 as potential targets of NF-κB that are involved in serum-induced hCSC proliferation.

The African swine fever virus MGF300-4L protein is associated with viral pathogenicity by promoting the autophagic degradation of IKKβ and increasing the stability of IκBα

ABSTRACT African swine fever (ASF) is a highly contagious, often fatal viral disease caused by African swine fever virus (ASFV) that imposes a substantial economic burden on the global pig industry each year. When screening for the regulation of virus replication genes in the left variable region of the ASFV genome, we observed a notable reduction in ASFV replication following the deletion of the MGF300-4L gene. However, the role of MGF300-4L in ASFV infection remains unexplored. In this study, we found that MGF300-4L could effectively inhibit the production of proinflammatory cytokines IL-1β and TNF-α, which are regulated by the NF-κB signaling pathway. Mechanistically, we demonstrated that MGF300-4L interacts with IKKβ and promotes its lysosomal degradation via the chaperone-mediated autophagy. Meanwhile, the interaction between MGF300-4L and IκBα competitively inhibits the binding of the E3 ligase β-TrCP to IκBα, thereby inhibiting the ubiquitination-dependent degradation of IκBα. Remarkably, despite encoding other inhibitors of NF-κB, the MGF300-4L gene-deleted ASFV (Del4L) showed reduced virulence in pigs, indicating that MGF300-4L plays a critical role in ASFV pathogenicity. Importantly, the attenuation of Del4L was associated with a significant increase in the IL-1β and TNF-α during the early stages of infection in pigs. Our findings provide insights into the functions of MGF300-4L in ASFV pathogenicity, suggesting that MGF300-4L could be a promising target for developing novel strategies and live attenuated vaccines against ASF.

Targeting Neuroinflammation by Pharmacologic Downregulation of Inflammatory Pathways Is Neuroprotective in Protein Misfolding Disorders.

Neuroinflammation plays a crucial role in the development of neurodegenerative protein misfolding disorders. This category of progressive diseases includes, but is not limited to, Alzheimer's disease, Parkinson's disease, and prion diseases. Shared pathogenesis involves the accumulation of misfolded proteins, chronic neuroinflammation, and synaptic dysfunction, ultimately leading to irreversible neuronal loss, measurable cognitive deficits, and death. Presently, there are few to no effective treatments to halt the advancement of neurodegenerative diseases. We hypothesized that directly targeting neuroinflammation by downregulating the transcription factor, NF-κB, and the inflammasome protein, NLRP3, would be neuroprotective. To achieve this, we used a cocktail of RNA targeting therapeutics (SB_NI_112) shown to be brain-penetrant, nontoxic, and effective inhibitors of both NF-κB and NLRP3. We utilized a mouse-adapted prion strain as a model for neurodegenerative diseases to assess the aggregation of misfolded proteins, glial inflammation, neuronal loss, cognitive deficits, and lifespan. Prion-diseased mice were treated either intraperitoneally or intranasally with SB_NI_112. Behavioral and cognitive deficits were significantly protected by this combination of NF-κB and NLRP3 downregulators. Treatment reduced glial inflammation, protected against neuronal loss, prevented spongiotic change, rescued cognitive deficits, and significantly lengthened the lifespan of prion-diseased mice. We have identified a nontoxic, systemic pharmacologic that downregulates NF-κB and NLRP3, prevents neuronal death, and slows the progression of neurodegenerative diseases. Though mouse models do not always predict human patient success and the study was limited due to sample size and number of dosing methods utilized, these findings serve as a proof of principle for continued translation of the therapeutic SB_NI_112 for prion disease and other neurodegenerative diseases. Based on the success in a murine prion model, we will continue testing SB_NI_112 in a variety of neurodegenerative disease models, including Alzheimer's disease and Parkinson's disease.