NF-κB P65 Nuclear Translocation Research Articles

Fengshi Liuhe Decoction treatment for rheumatoid arthritis via the Fzd6/NF-κB signaling axis

To explore whether Fengshi Liuhe Decoction (FLD) alleviates rheumatoid arthritis (RA) via the Fzd6/NF-κB signaling axis. We used real-time quantitative PCR (qPCR) and western blotting (WB) to determine the genes of the frizzled (Fzd) protein 1- Fzd protein 10 that are significantly differentially expressed between normal rat fibroblast-like synoviocyte (FLS) and collagen II-induced arthritis (CIA) rat FLS. Next, we used enzyme-linked immunosorbent assay (ELISA) to evaluate the levels of inflammatory factors in cell culture supernatant to determine the ability of FLD to ameliorate RA. Finally, we employed WB to detect the key gene expression in protein levels of the Fzd6/NF-κB signaling axis among normal rat FLS, CIA rat FLS, and FLD-treated CIA rat FLS. Our results showed that Fzd6 expression was significantly higher in CIA rat FLS at both the mRNA and protein levels than in normal rat FLS. FLD was found to downregulate Fzd6 and inflammatory factors, including COX-2, IL-8, and TNF-α, at both the mRNA and protein levels. FLD was also found to downregulate the total protein levels of Fzd6 and the NF-κB signaling pathway key gene phosphorylation of p-p65/p65 and p-IκBα/IκBα. Moreover, FLD inhibited the nuclear translocation of NF-κB p65 in CIA rat FLS. FLD can alleviate inflammation of CIA rat FLS via the Fzd6/NF-κB signaling axis.

Asiatic acid alleviates vascular remodeling in BAPN-induced aortic dissection through inhibiting NF-κB p65/CX3CL1 signaling.

Inflammation assumes a pivotal role in the aortic remodeling of aortic dissection (AD). Asiatic acid (AA), a triterpene compound, is recognized for its strong anti-inflammatory properties. Yet, its effects on β-aminopropionitrile (BAPN)-triggered AD have not been clearly established. The objective is to determine whether AA attenuates adverse aortic remodeling in BAPN-induced AD and clarify potential molecular mechanisms. Invitro studies, RAW264.7 cells pretreated with AA were challenged with lipopolysaccharide (LPS), and then the vascular smooth muscle cells (VSMCs)-macrophage coculture system was established to explore intercellular interactions. To induce AD, male C57BL/6J mice at three weeks of age were administered BAPN at a dosage of 1 g/kg/d for four weeks. To decipher the mechanism underlying the effects of AA, RNA sequencing analysis was conducted, with subsequent validation of these pathways through cellular experiments. AA exhibited significant suppression of M1 macrophage polarization. In the cell coculture system, AA facilitated the transformation of VSMCs into a contractile phenotype. In the mouse model of AD, AA strikingly prevented the BAPN-induced increases in inflammation cell infiltration and extracellular matrix degradation. Mechanistically, RNA sequencing analysis revealed a substantial upregulation of CX3CL1 expression in BAPN group but downregulation in AA-treated group. Additionally, it was observed that the upregulation of CX3CL1 negated the beneficial impact of AA on the polarization of macrophages and the phenotypic transformation of VSMCs. Crucially, our findings revealed that AA is capable of downregulating CX3CL1 expression, accomplishing this by obstructing the nuclear translocation of NF-κB p65. The findings indicate that AA holds promise as a prospective treatment for adverse aortic remodeling by suppressing the activity of NF-κB p65/CX3CL1 signaling pathway.

Novel trifluoromethyl ketone derivatives as oral cPLA2/COX-2 dual inhibitors for resolution of inflammation in rheumatoid arthritis

Thirty-five trifluoromethyl hydrazones and seventeen trifluoromethyl oxime esters were designed and synthesized via molecular hybridization. All the target compounds were initially screened for in vitro anti-inflammatory activity by assessing their inhibitory effect on NO release in LPS-stimulated RAW264.7 cells, and the optimal compound was finally identified as 2-(3-Methoxyphenyl)-N'-((6Z,9Z,12Z,15Z)-1,1,1-trifluorohenicosa-6,9,12,15-tetraen-2-ylidene)acetohydrazide (F26, IC50 = 4.55 ± 0.92 μM) with no cytotoxicity. Moreover, F26 potently reduced the production of PGE2 in LPS-stimulated RAW264.7 cells compared to indomethacin. The interaction of F26 with COX-2 and cPLA2 was directly verified by the CETSA technique. F26 was found to modulate the phosphorylation levels of p38 MAPK and NF-κB p65, as well as the protein expression of IκB, cPLA2, COX-2, and iNOS in LPS-stimulated rat peritoneal macrophages. Additionally, F26 was observed to prevent the nuclear translocation of NF-κB p65 in LPS-stimulated rat peritoneal macrophages by immunofluorescence localization. Therefore, the aforementioned in vitro experiments demonstrated that F26 blocked the p38 MAPK and NF-κB pathways by binding to COX-2 and cPLA2. In the adjuvant-induced arthritis model, F26 demonstrated a significant effect in preventing arthritis symptoms and inflammatory status in rats, exerting an immunomodulatory role by regulating the homeostasis between Th17 and Treg through inhibition of the p38 MAPK/cPLA2/COX-2/PGE2 and NF-κB pathways. Encouragingly, F26 caused less acute ulcerogenicity in rats at a dose of 50 mg/kg compared to indomethacin. Overall, F26 is a promising candidate worthy of further investigation for treating inflammation and associated pain with lesser gastrointestinal irritation, as well as other symptoms in which cPLA2 and COX-2 are implicated in the pathophysiology.

PCV2 Induced Endothelial Derived IL-8 Affects MoDCs Maturation Mainly via NF-κB Signaling Pathway.

Porcine circovirus type 2 (PCV2) infection can cause immunosuppressive diseases in pigs. Vascular endothelial cells (VECs), as the target cells for PCV2, play an important role in the immune response and inflammatory regulation. Endothelial IL-8, which is produced by porcine hip artery endothelial cells (PIECs) infected with PCV2, can inhibit the maturation of monocyte-derived dendritic cells (MoDCs). Here, we established a co-culture system of MoDCs and different groups of PIECs to further investigate the PCV2-induced endothelial IL-8 signaling pathway that drives the inhibition of MoDC maturation. The differentially expressed genes related to MoDC maturation were mainly enriched in the NF-κB and JAK2-STAT3 signaling pathways. Both the NF-κB related factor RELA and JAK2-STAT3 signaling pathway related factors (IL2RA, JAK, STAT2, STAT5, IL23A, IL7, etc.) decreased significantly in the IL-8 up-regulated group, and increased significantly in the down-regulated group. The expression of NF-κB p65 in the IL-8 up-regulated group was reduced significantly, and the expression of IκBα was increased significantly. Nuclear translocation of NF-κB p65 was inhibited, while the nuclear translocation of p-STAT3 was increased in MoDCs in the PCV2-induced endothelial IL-8 group. The results of treatment with NF-κB signaling pathway inhibitors showed that the maturation of MoDCs was inhibited and the expression of IL-12 and GM-CSF at mRNA level were lower. Inhibition of the JAK2-STAT3 signaling pathway had no significant effect on maturation, and the expression of IL-12 and GM-CSF at mRNA level produced no significant change. In summary, the NF-κB signaling pathway is the main signaling pathway of MoDC maturation, and is inhibited by the PCV2-induced up-regulation of endothelial-derived IL-8.

Therapy-induced senescent tumor cell-derived extracellular vesicles promote colorectal cancer progression through SERPINE1-mediated NF-κB p65 nuclear translocation

BackgroundCellular senescence frequently occurs during anti-cancer treatment, and persistent senescent tumor cells (STCs) unfavorably promote tumor progression through paracrine secretion of the senescence-associated secretory phenotype (SASP). Extracellular vesicles (EVs) have recently emerged as a novel component of the SASP and primarily mediate the tumor-promoting effect of the SASP. Of note, the potential effect of EVs released from STCs on tumor progression remains largely unknown.MethodsWe collected tumor tissues from two cohorts of colorectal cancer (CRC) patients to examine the expression of p16, p21, and SERPINE1 before and after anti-cancer treatment. Cohort 1 included 22 patients with locally advanced rectal cancer (LARC) who received neoadjuvant therapy before surgical resection. Cohort 2 included 30 patients with metastatic CRC (mCRC) who received first-line irinotecan-contained treatment. CCK-8, transwell, wound-healing assay, and tumor xenograft experiments were carried out to determine the impacts of EVs released from STCs on CRC progression in vitro and in vivo. Quantitative proteomic analysis was applied to identify protein cargo inside EVs secreted from STCs. Immunoprecipitation and mass spectrometer identification were utilized to explore the binding partners of SERPINE1. The interaction of SERPINE1 with p65 was verified by co-immunoprecipitation, and their co-localization was confirmed by immunofluorescence.ResultsChemotherapeutic agents and irradiation could potently induce senescence in CRC cells in vitro and in human CRC tissues. The more significant elevation of p16 and p21 expression in patients after anti-cancer treatment displayed shorter disease-free survival (DFS) for LARC or progression-free survival (PFS) for mCRC. We observed that compared to non-STCs, STCs released an increased number of EVs enriched in SERPINE1, which further promoted the progression of recipient cancer cells. Targeting SERPINE1 with a specific inhibitor, tiplaxtinin, markedly attenuated the tumor-promoting effect of STCs-derived EVs. Additionally, the patients with greater increment of SERPINE1 expression after anti-cancer treatment had shorter DFS for LARC or PFS for mCRC. Mechanistically, SERPINE1 bound to p65, promoting its nuclear translocation and subsequently activating the NF-κB signaling pathway.ConclusionsWe provide the in vivo evidence of the clinical prognostic implications of therapy-induced senescence. Our results revealed that STCs were responsible for CRC progression by producing large amounts of EVs enriched in SERPINE1. These findings further confirm the crucial role of therapy-induced senescence in tumor progression and offer a potential therapeutic strategy for CRC treatment.

Novel silicene-mesoporous silica nanoparticles conjugated gemcitabine induced cellular apoptosis via upregulating NF-κB p65 nuclear translocation suppresses pancreatic cancer growth in vitro and in vivo

Pancreatic cancer’s high fatality rates stem from its resistance to systemic drug delivery and aggressive metastasis, limiting the efficacy of conventional treatments. In this study, two-dimensional ultrathin silicene nanosheets were initially synthesized and near-infrared-responsive two-dimensional silicene-mesoporous silica nanoparticles (SMSNs) were successfully constructed to load the clinically-approved conventional pancreatic cancer chemotherapeutic drug gemcitabine. Experiments on nanoparticle characterization show that they have excellent photothermal conversion ability and stability. Then silicene-mesoporous silica nanoparticles loaded with gemcitabine nanoparticles (SMSN@G NPs) were employed in localized photothermal therapy to control pancreatic tumor growth and achieve therapeutic effects. Our research confirmed the functionality of SMSN@G NPs through immunoblotting and apoptotic assays, demonstrating its capacity to enhance the nuclear translocation of the NF-κB p65, further affect the protein levels of apoptosis-related genes, induce the apoptosis of tumor cells, and ultimately inhibit the growth of the tumor. Additionally, the study assessed the inhibitory role of SMSN@G NPs on pancreatic neoplasm growth in vivo, revealing its excellent biocompatibility. SMSN@G NPs have a nice application prospect for anti-pancreatic tumors.

Diosgenin protects against cationic bovine serum albumin-induced membranous glomerulonephritis by attenuating oxidative stress and renal inflammation via the NF-κB pathway

Context Membranous glomerulonephritis (MGN) is a leading cause of nephrotic syndrome in adults. Diosgenin (DG) has been reported to exert antioxidative and anti-inflammatory effects. Objective To investigate the renoprotective activity of DG in a cationic bovine serum albumin-induced rat model of MGN. Materials and methods Fourty male Sprague-Dawley rats were randomized into four groups. The MGN model was established and treated with a DG dose (10 mg/kg) and a positive control (TPCA1, 10 mg/kg), while normal control and MGN groups received distilled water by gavage for four consecutive weeks. At the end of the experiment, 24 h urinary protein, biochemical indices, oxidation and antioxidant levels, inflammatory parameters, histopathological examination, immunohistochemistry and immunoblotting were evaluated. Results DG significantly ameliorated kidney dysfunction by decreasing urinary protein (0.56-fold), serum creatinine (SCr) (0.78-fold), BUN (0.71-fold), TC (0.66-fold) and TG (0.73-fold) levels, and increasing ALB (1.44-fold). DG also reduced MDA (0.82-fold) and NO (0.83-fold) levels while increasing the activity of SOD (1.56-fold), CAT (1.25-fold), glutathione peroxidase (GPx) (1.55-fold) and GSH (1.81-fold). Furthermore, DG reduced Keap1 (0.76-fold) expression, Nrf2 nuclear translocation (0.79-fold), and induced NQO1 (1.25-fold) and HO-1 (1.46-fold) expression. Additionally, DG decreased IL-2 (0.55-fold), TNF-α (0.80-fold) and IL-6 (0.75-fold) levels, and reduced protein expression of NF-κB p65 (0.80-fold), IKKβ (0.93-fold), p-IKKβ (0.89-fold), ICAM-1 (0.88-fold), VCAM-1 (0.91-fold), MCP-1 (0.88-fold) and E-selectin (0.87-fold), and also inhibited the nuclear translocation of NF-κB p65 (0.64-fold). Discussion and conclusions The results suggest a potential therapeutic benefit of DG against MGN due to the inhibition of the NF-κB pathway, supporting the need for further clinical trials.

Chlojaponilactone B Attenuates THP-1 Macrophage Pyroptosis by Inhibiting the TLR/MyD88/NF-κB Pathway.

Pyroptosis, an innate immune response, plays a crucial role in the pathological process of inflammatory diseases. Although pyroptosis blockade is considered a potential therapeutic strategy, no ideal candidate drug has been identified. The natural product Chojaponilactone B (CJB) has demonstrated anti-inflammatory effects, but its role in macrophage pyroptosis has not been studied. This study aimed to investigate the effect and mechanism of CJB in inhibiting macrophage pyroptosis. Using an LPS/ATP-induced THP-1 macrophage pyroptosis model, we found that CJB significantly inhibited pyroptosis and reduced the levels of NLRP3, caspase 1, N-GSDMD, and inflammatory cytokines IL-1β and IL-18. RNA sequencing analysis revealed that CJB interfered with LPS/ATP-induced THP-1 macrophage gene expression, suggesting involvement in anti-inflammatory and anti-pyroptotic signaling pathways. Additionally, CJB suppressed LPS/ATP-induced elevations in TLRs, MyD88, pro-IL-1β, and NF-κB and blocked NF-κB p65 nuclear translocation. In summary, CJB inhibits NLRP3 activation and macrophage pyroptosis through the TLR/MyD88/NF-κB pathway, providing important evidence for its development as a potential drug for treating pyroptosis-related inflammatory diseases.

Platycodon grandiflorus polysaccharide inhibits the inflammatory response of 3D4/21 cells infected with PCV2

Porcine circovirus type 2 (PCV2) infection cause multi-systemic inflammation in pigs. Platycodon grandiflorus polysaccharide (PGPSt) has been reported to have the effects of immune regulation and disease resistance. Nevertheless, the role and mechanism of PGPSt in the inflammatory response of 3D4/21 cells induced by PCV2 infection remain unclear. The present study aims to investigate effects of PGPSt on inflammatory response and its possible underlying mechanisms in vitro models. Cells were treated with PCV2 for 36 h to construct a cell inflammation model. The 3D4/21 cell lines were pretreated with or without PGPSt, and the changes of inflammation-related markers and the signaling pathway were detected by CCK-8, ELISA, qPCR and Western blot. The results showed that PGPSt was non-toxic to cells and protected PCV2-infected cells from inflammatory damage. PGPSt could significantly inhibit the high acetylation of histone H3 (AcH3) and histone H4 (AcH4), down-regulate HAT and up-regulate HDAC activity, and reduce the expression of pro-inflammatory enzymes iNOS and COX-2 proteins levels. Then the levels of IL-1β, IL-6 and TNF-α were significantly inhibited, and the level of IL-10 was promoted. We also observed that PGPSt inhibited the phosphorylation of p65, p38 and Erk1/2, which subsequently inhibited nuclear translocation of NF-κB p65 to express pro-inflammatory factors. In conclusion, PGPSt can reduce the inflammatory response by regulating histone acetylation, reducing the release of inflammatory factors, reducing the expression of pro-inflammatory enzymes, and inhibiting the activation of NF-κB and MAPKs signaling pathways. This suggests that PGPSt had an anti-inflammatory effect on the inflammatory response caused by PCV2 infection, which provided theoretical data support for the research.

A mixture of extracts from natural ingredients reduces the neurotoxic polarization of microglia via modulating NF-κB/NF-E2-related factor 2 activation.

Neurotoxic microglia-provoked neuroinflammation is implicated in cognitive decline in Alzheimer's disease (AD). Supplementation with Ginkgo biloba, phosphatidylserine, Curcuma longa, and propolis is reported to improve the cognitive functions of elderly people; however, the underlying mechanisms of this combination of natural ingredients are unknown. We investigated the effects of a mixture of extracts from propolis, Coffea arabica, Gotu kola, phosphatidylserine, Ginkgo biloba, and Curcuma longa (mixture) on microglia polarization after exposure to amyloid β1-42 (Aβ1-42, 1 μM) and lipopolysaccharide from Porphyromonas gingivalis (PgLPS, 1 μg/mL), using MG6 and BV2 microglial cells. Exposure to Aβ1-42 and PgLPS (AL) raised the mRNA expression of IL-1β, TNF-α, and IL-6, nuclear translocation of p65 NF-κB in MG6 cells and BV2 cells, and mitochondrial reactive oxygen species (ROS) production in MG6 cells. The mixture dramatically suppressed the mRNA expression of IL-1β, TNF-α, and IL-6, but significantly promoted that of IL-10, TGFβ1, and BDNF in AL-exposed MG6 and BV2 cells. Furthermore, the mixture significantly suppressed the nuclear translocation of p65 NF-κB but significantly promoted that of NF-E2-related factor 2 (Nrf2) in AL-exposed MG6 and BV2 cells. Furthermore, the mixture significantly ameliorated mitochondrial ROS production but increased mitochondrial membrane potential in MG6 cells. These observations strongly suggest that the mixture demotes the neuropathic polarization of microglia by modulating NF-κB/Nrf2 activation and improving mitochondrial functions. This study supplies the potential mechanisms of the efficacy of a combination of natural ingredients that can be applied in the prevention of cognitive decline in AD and aging by targeting microglia-mediated neuroinflammation.

Levistilide A Exerts a Neuroprotective Effect by Suppressing Glucose Metabolism Reprogramming and Preventing Microglia Polarization Shift: Implications for Parkinson's Disease.

The microglia, displaying diverse phenotypes, play a significant regulatory role in the development, progression, and prognosis of Parkinson's disease. Research has established that glycolytic reprogramming serves as a critical regulator of inflammation initiation in pro-inflammatory macrophages. Furthermore, the modulation of glycolytic reprogramming has the potential to reverse the polarized state of these macrophages. Previous studies have shown that Levistilide A (LA), a phthalide component derived from Angelica sinensis, possesses a range of pharmacological effects, including anti-inflammatory, antioxidant, and neuroprotective properties. In our study, we have examined the impact of LA on inflammatory cytokines and glucose metabolism in microglia induced by lipopolysaccharide (LPS). Furthermore, we explored the effects of LA on the AMPK/mTOR pathway and assessed its neuroprotective potential both in vitro and in vivo. The findings revealed that LA notably diminished the expression of M1 pro-inflammatory factors induced by LPS in microglia, while leaving M2 anti-inflammatory factor expression unaltered. Additionally, it reduced ROS production and suppressed IκB-α phosphorylation levels as well as NF-κB p65 nuclear translocation. Notably, LA exhibited the ability to reverse microglial glucose metabolism reprogramming and modulate the phosphorylation levels of AMPK/mTOR. In vivo experiments further corroborated these findings, demonstrating that LA mitigated the death of TH-positive dopaminergic neurons and reduced microglia activation in the ventral SNpc brain region of the midbrain and the striatum. In summary, LA exhibited neuroprotective benefits by modulating the polarization state of microglia and altering glucose metabolism, highlighting its therapeutic potential.

Acacetin inhibits inflammation by blocking MAPK/NF-κB pathways and NLRP3 inflammasome activation.

Objective: Our preliminary research indicates that acacetin modulates the nucleotide-binding oligomerization domain (NOD)-like receptor pyrin domain containing 3 (NLRP3) inflammasome, providing protection against Alzheimer's Disease (AD) and cerebral ischemic reperfusion injury. The mechanisms of acacetin to inhibit the activation of the NLRP3 inflammasome remain fully elucidated. This study aims to investigate the effects and potential mechanisms of acacetin on various agonists induced NLRP3 inflammasome activation. Methods: A model for the NLRP3 inflammasome activation was established in mouse bone marrow-derived macrophages (BMDMs) using Monosodium Urate (MSU), Nigericin, Adenosine Triphosphate (ATP), and Pam3CSK4, separately. Western blot analysis (WB) was employed to detect Pro-caspase-1, Pro-Interleukin-1β (Pro-IL-1β) in cell lysates, and caspase-1, IL-1β in supernatants. Enzyme-Linked Immunosorbent Assay (ELISA) was used to measured the release of IL-1β, IL-18, and Tumor Necrosis Factor-alpha (TNF-α) in cell supernatants to assess the impact of acacetin on NLRP3 inflammasome activation. The lactate dehydrogenase (LDH) release was also assessed. The Nuclear Factor Kappa B (NF-κB) and Mitogen-Activated Protein Kinase (MAPK) signaling pathways related proteins were evaluated by WB, and NF-κB nuclear translocation was observed via laser scanning confocal microscopy (LSCM). Disuccinimidyl Suberate (DSS) cross-linking was employed to detect oligomerization of Apoptosis-associated Speck-like protein containing a Caspase Recruitment Domain (ASC), and LSCM was also used to observe Reactive Oxygen Species (ROS) production. Inductively Coupled Plasma (ICP) and N-(6-methoxyquinolyl) acetoethyl ester (MQAE) assays were utilized to determined the effects of acacetin on the efflux of potassium (K+) and chloride (Cl-) ions. Results: Acacetin inhibited NLRP3 inflammasome activation induced by various agonists, reducing the release of TNF-α, IL-1β, IL-18, and LDH. It suppressed the expression of Lipopolysaccharides (LPS)-activated Phosphorylated ERK (p-ERK), p-JNK, and p-p38, inhibited NF-κB p65 phosphorylation and nuclear translocation. Acacetin also reduced ROS production and inhibited ASC aggregation, thus suppressing NLRP3 inflammasome activation. Notably, acacetin did not affect K+ and Cl-ions efflux during the activation process. Conclusion: Acacetin shows inhibitory effects on both the priming and assembly processes of the NLRP3 inflammasome, positioning it as a promising new candidate for the treatment of NLRP3 inflammasome-related diseases.

Mesenchymal Stromal Cell Therapy Alleviates Ovalbumin-Induced Chronic Airway Remodeling by Suppressing M2 Macrophage Polarization.

Chronic asthma is characterized by airway hyperresponsiveness, inflammation, and remodeling. Previous studies have shown that mesenchymal stromal/stem cells (MSCs) exert anti-inflammatory effects on asthma via regulation of the immune cells. However, the therapeutic mechanism of MSCs, especially the mechanism of airway remodeling in chronic asthma, remains to be elucidated. Here, we aimed to investigate the therapeutic effect of MSCs on airway remodeling in chronic asthma and explored the mechanisms by analyzing the polarization phenotype of macrophages in the lungs. We established a mouse model of chronic asthma induced by ovalbumin (OVA) and evaluated the effect of MSCs on airway remodeling. The data showed that MSCs treatment before the challenge exerted protective effects on OVA-induced chronic asthma, i.e., decreased the inflammatory cell infiltration, Th2 cytokine levels, subepithelial extracellular matrix deposition, and transforming growth factor β (TGF-β)/Smad signaling. Additionally, we found that MSCs treatment markedly suppressed macrophage M2 polarization in lung tissue. At the same time, MSCs treatment inhibited NF-κB p65 nuclear translocation, ER stress, and oxidative stress in the OVA-induced chronic allergic airway remodeling mice model. In conclusion, these results demonstrated that MSCs treatment prevents OVA-induced chronic airway remodeling by suppressing macrophage M2 polarization, which may be associated with the dual inhibition of ER stress and oxidative stress. This discovery may provide a new theoretical basis for the future clinical application of MSCs.

Identifying Marine-Derived Tanzawaic Acid Derivatives as Novel Inhibitors against Osteoclastogenesis and Osteoporosis via Downregulation of NF-κB and NFATc1 Activation.

To discover novel osteoclast-targeting antiosteoporosis leads from natural products, we identified 40 tanzawaic acid derivatives, including 22 new ones (1-8, 14-19, 27-32, 37, and 38), from the South China Sea mangrove-derived fungus Penicillium steckii SCSIO 41025. Penicisteck acid F (2), one of the new derivatives showing the most potent NF-κB inhibitory activity, remarkably inhibited osteoclast generation in vitro. Mechanistically, 2 reduced RANKL-induced IκBα degradation, NF-κB p65 nuclear translocation, the activation and nuclear translocation of NFATc1, and the relevant mRNA expression. NF-κB p65 could be a potential molecular target for 2, which has been further determined by the cellular thermal shift assay, surface plasmon resonance, and the gene knock-down assay. Moreover, 2 could also alleviate osteoporosis in ovariectomized mice by reducing the quantities of osteoclasts. Our finding offered a novel potential inhibitor of osteoclastogenesis and osteoporosis for further development of potent antiosteoporosis agents.

NKG2D knockdown improves hypoxic-ischemic brain damage by inhibiting neuroinflammation in neonatal mice

Hypoxic-ischemic brain damage (HIBD) is a leading cause of neonatal death and neurological dysfunction. Neuroinflammation is identified as one of the crucial pathological mechanisms after HIBD, and natural killer group 2 member D (NKG2D) is reported to be implicated in the pathogenesis of immunoinflammatory diseases. However, the role of NKG2D in neonatal HIBD is seldomly investigated. In this study, a neonatal mice model of HIBD was induced, and the role of the NKG2D in neuroinflammation and brain injury was explored by intracerebroventricular injection of lentivirus to knockdown NKG2D in neonatal mice with HIBD. The results showed that a significant increase in NKG2D protein level in the brain of neonatal mice with HIBD. The NKG2D knockdown in the brain significantly alleviated cerebral infarction, neurobehavioral deficits, and neuronal loss in neuronal HIBD. Moreover, the neuroprotective effect of NKG2D knockdown was associated with inhibition of the activation of microglia and astrocytes, expression of NKG2D ligands (NKG2DLs) and DAP10, and the nuclear translocation of NF-κB p65. Our findings reveal NKG2D knockdown may exert anti-inflammatory and neuroprotective effects in the neonatal mice with HIBD through downregulation of NKG2D/NKG2DLs/DAP10/NF-κB pathway. These results suggest that NKG2D may be a potential target for the treatment of neonatal HIBD.

Aucubin protects against myocardial ischemia-reperfusion injury by regulating STAT3/NF-κB/HMGB-1 pathway

The main characteristics of the myocardial ischemia/reperfusion injury (MI/RI) are oxidative stress, apoptosis, and an inflammatory response. Aucubin (AU) is an iridoid glycoside that possesses various biological properties and has been discovered to demonstrate antioxidant and anti-inflammatory impacts in pathological processes, such as ischemia-reperfusion. The objective of this research was to investigate if AU treatment could mitigate myocardial inflammation and apoptosis caused by ischemia/reperfusion (I/R) in both laboratory and animal models, and to elucidate its underlying mechanism.By ligating the coronary artery on the left anterior descending side, a successful MI/RI rat model was created. Additionally, H9C2 cells were subjected to hypoxia/reoxygenation (H/R) in order to imitate the injury caused by ischemia/reperfusion (I/R). Furthermore, various concentrations of AU were administered to H9C2 cells or rats before H/R stimulation or myocardial I/R surgery, respectively. In vitro, the assessment was conducted on cardiac function, inflammatory markers, and myocardial pathology. In vivo, we examined the viability of cells, as well as factors related to apoptosis and oxidative stress. Furthermore, the presence of proteins belonging to the STAT3/NF-κB/HMGB1 signaling pathway was observed both in vivo and in vitro.AU effectively improved cardiomyocyte injury caused by H/R and myocardial injury caused by I/R. Furthermore, AU suppressed the production of reactive oxygen species and inflammatory molecules (TNF-alpha, IL-1β, and IL-6) and proteins associated with cell death (caspase-3 and Bax), while enhancing the levels of anti-inflammatory agents (IL-10) and the anti-apoptotic protein Bcl-2.AU mechanistically affected the phosphorylation of STAT3 at the Ser727 site and Tyr705 following H/R by modulating the signaling pathway involving signal transducer and activator of transcription 3 (STAT3)/nuclear factor-κB (NF-κB)/high mobility group box 1 (HMGB1), while also suppressing the nuclear translocation of NF-κB p65 and HMGB1 exonucleation.In conclusion, the use of AU treatment might offer protection against myocardial infarction and injury by reducing oxidative stress, suppressing apoptosis, and mitigating inflammation. The regulation of the STAT3/NF-κB/HMGB-1 pathway may contribute to this phenomenon by affecting STAT3 phosphorylation and controlling NF-κB and HMGB-1 translocation. Contributes to identifying possible objectives for myocardial ischemia/reperfusion damage.

MiR-26a-5p Attenuates Oxidative Stress and Inflammation in Diabetic Retinopathy through the USP14/NF-κB Signaling Pathway.

Diabetic retinopathy (DR) is an ocular disease caused by diabetes and may lead to vision impairment and even blindness. Oxidative stress and inflammation are two key pathogenic factors of DR. Recently, regulatory roles of different microRNAs (miRNAs) in DR have been widely verified. miR-26a-5p has been confirmed to be a potential biomarker of DR. Nevertheless, the specific functions of miR-26a-5p in DR are still unclear. Primary cultured mouse retinal Müller cells in exposure to high glucose (HG) were used to establish an in vitro DR model. Müller cells were identified via morphology observation under phase contrast microscope and fluorescence staining for glutamine synthetase. The in vivo animal models for DR were constructed using streptozotocin-induced diabetic C57BL/6 mice. Western blotting was performed to quantify cytochrome c protein level in the cytoplasm and mitochondria of Müller cells and to measure protein levels of glial fibrillary acidic protein (GFAP), ubiquitin-specific peptidase 14 (USP14), as well as factors associated with NF-κB signaling (p-IκBα, IκBα, p-p65, and p65) in Müller cells or murine retinal tissues. ROS production was detected by CM-H2DCFDA staining, and the concentration of oxidative stress markers (MDA, SOD, and CAT) was estimated by using corresponding commercial kits. Quantification of mRNA expression was conducted by RT-qPCR analysis. The concentration of proinflammatory factors (TNF-α, IL-1β, and IL-6) was evaluated by ELISA. Hematoxylin-eosin staining for murine retinal tissues was performed for histopathological analysis. Immunofluorescence staining was conducted to determine NF-κB p65 nuclear translocation in Müller cells. Furthermore, the interaction between miR-26a-5p and USP14 was verified via the luciferase reporter assays. HG stimulation contributed to Müller cell dysfunction by inducing inflammation, oxidative injury, and mitochondrial damage to Müller cells. miR-26a-5p was downregulated in Müller cells under HG condition, and overexpression of miR-26a-5p relieved HG-induced Müller cell dysfunction. Moreover, miR-26a-5p targeted USP14 and inversely regulated USP14 expression. Additionally, HG-evoked activation of NF-κB signaling was suppressed by USP14 knockdown or miR-26a-5p upregulation. Rescue assays showed that the protective impact of miR-26a-5p upregulation against HG-induced Müller cell dysfunction was reversed by USP14 overexpression. Furthermore, USP14 upregulation and activation of NF-κB signaling in the retinas of DR mice were detected in animal experiments. Injection with miR-26a-5p agomir improved retinal histopathological injury and weakened the concentration of proinflammatory cytokines and oxidative stress markers in the retinas of DR mice. miR-26a-5p inhibits oxidative stress and inflammation in DR progression by targeting USP14 and inactivating the NF-κB signaling pathway.

Inflammatory responses and barrier disruption in the trachea of chicks following Mycoplasma gallisepticum infection: a focus on the TNF-α-NF-κB/MLCK pathway

Mycoplasma gallisepticum (MG) can induce persistent inflammatory damage to the tracheal mucosa of poultry and cause chronic respiratory diseases in chickens. To further investigate the mechanism of MG-induced injury to the tracheal mucosa, we used chick embryo tracheal organ culture (TOC) as a model to study the invasion and reproduction of MG, the effect of MG on tracheal morphology, and the potential factors that promote MG tissue invasion. The results showed that MG infection significantly damaged the tracheal epithelial structure and weakened tracheal epithelial barrier function; MG also increased the occurrence of bacterial displacement, with a significant (p < 0.05) increase in the bacterial load of the infected TOCs at 5 and 7 days post-infection. In addition, MG significantly (p < 0.05) increased the expression levels of inflammatory cytokines, such as TNF-α, interleukin-1β (IL-1β), and IL-6, and activated the NF-κB signalling pathway, leading to increased nuclear translocation of NF-κB p65. Simultaneously, the map kinase pathway (MAPK) was activated. This activation might be associated with increased myosin light chain (MLC) phosphorylation, which could lead to actin-myosin contraction and disruption of tight junction (TJ) protein function, potentially compromising epithelial barrier integrity and further catalysing MG migration into tissues. Overall, our results contribute to a better understanding of the interaction between MG and the host, provide insight into the mechanisms of damage to the tracheal mucosa induced by MG infection, and provide new insights into the possible pathways involved in Mycoplasma gallisepticum infection in vivo.

Low-level Nd:YAG laser inhibiting inflammation and oxidative stress in human gingival fibroblasts via AMPK/SIRT3 axis

ObjectivePhotobiomodulation is extensively employed in the management of chronic inflammatory diseases such as periodontitis because of its anti-inflammatory and antioxidant effects. This study used low-level Nd:YAG laser to investigate the mechanism of photobiomodulation as well as the role of adenosine monophosphate-activated protein kinase (AMPK) and Sirtuins (SIRT) 3 in it, providing new clues for the treatment of periodontitis. MethodsHuman gingival fibroblasts (HGFs) were extracted from gingiva and stimulated with LPS. The suitable parameters of Nd:YAG laser were chosen for subsequent experiments by detecting cell viability. We assessed the level of inflammation and oxidative stress as well as AMPK and SIRT3. The mechanism for AMPK targeting SIRT3 modulating the anti-inflammatory and antioxidant effects of photobiomodulation was explored by the AMPK inhibitor (Compound C) test, cell transfection, western blot, and immunofluorescence. ResultsHGFs were isolated and identified, followed by the identification of optimal Nd:YAG laser parameters (60 mJ, 15 Hz, 10s) for subsequent experimentation. With this laser, inflammatory factors (IL-6, TNF-α, COX2, and iNOS) decreased as well as the phosphorylation and nuclear translocation of NFκB-P65. SOD2 was up-regulated but reactive oxygen species (ROS) was down-regulated. The laser treatment exhibited enhancements in AMPK phosphorylation and SIRT3 expression. The above effects could all be reversed by Compound C. Silencing AMPK or SIRT3 by siRNA, the down-regulation of COX2, iNOS, and ROS by laser was inhibited. SIRT3 was down-regulated when the AMPK was silenced. ConclusionLow-level Nd:YAG laser activated AMPK-SIRT3 signaling pathway, facilitating the anti-inflammatory and antioxidative activity.

Diosmin ameliorates renal fibrosis through inhibition of inflammation by regulating SIRT3-mediated NF-κB p65 nuclear translocation

BackgroundRenal fibrosis is considered an irreversible pathological process and the ultimate common pathway for the development of all types of chronic kidney diseases and renal failure. Diosmin is a natural flavonoid glycoside that has antioxidant, anti-inflammatory, and antifibrotic activities. However, whether Diosmin protects kidneys by inhibiting renal fibrosis is unknown. We aimed to investigate the role of Diosmin in renal interstitial fibrosis and to explore the underlying mechanisms.MethodsThe UUO mouse model was established and gavaged with Diosmin (50 mg/kg·d and 100 mg/kg·d) for 14 days. HE staining, Masson staining, immunohistochemistry, western blotting and PCR were used to assess renal tissue injury and fibrosis. Elisa kits were used to detect the expression levels of IL-1β, IL-6, and TNF-α and the activity of SIRT3 in renal tissues. In addition, enrichment maps of RNA sequencing analyzed changes in signaling pathways. In vitro, human renal tubular epithelial cells (HK-2) were stimulated with TGF-β1 and then treated with diosmin (75 μM). The protein and mRNA expression levels of SIRT3 were detected in the cells. In addition, 3-TYP (selective inhibitor of SIRT3) and SIRT3 small interfering RNA (siRNA) were used to reduce SIRT3 levels in HK-2.ResultsDiosmin attenuated UUO-induced renal fibrosis and TGF-β1-induced HK-2 fibrosis. In addition, Diosmin reduced IL-1β, IL-6, and TNF-α levels in kidney tissues and supernatants of HK-2 medium. Interestingly, Diosmin administration increased the enzymatic activity of SIRT3 in UUO kidneys. In addition, Diosmin significantly increased mRNA and protein expression of SIRT3 in vitro and in vivo. Inhibition of SIRT3 expression using 3-TYP or SIRT3 siRNA abolished the anti-inflammatory effects of diosmin in HK-2 cells. Enrichment map analysis by RNA sequencing indicates that the nuclear factor-kappa B (NF-κB) signaling pathway was inhibited in the Diosmin intervention group. Furthermore, we found that TGF-β1 increased the nuclear expression of nuclear NF-κB p65 but had little significant effect on the total intracellular expression of NF-κB p65. Additionally, Diosmin reduced TGF-β1-caused NF-κB p65 nuclear translocation. Knockdown of SIRT3 expression by SIRT3 siRNA increased the nuclear expression of NF-κB p65 and abolished the inhibition effect of Diosmin in NF-κB p65 expression.ConclusionsDiosmin reduces renal inflammation and fibrosis, which is contributed by inhibiting nuclear translocation of NF-κB P65 through activating SIRT3.