Nuclear factor-κB Signaling Research Articles

Epigenetic Mechanisms of Aluminum-Induced Neurotoxicity and Alzheimer's Disease: A Focus on Non-Coding RNAs.

Aluminum (Al) is known to induce neurotoxic effects, potentially contributing to Alzheimer's disease (AD) pathogenesis. Recent studies suggest that epigenetic modification may contribute to Al neurotoxicity, although the mechanisms are still debatable. Therefore, the objective of the present study was to summarize existing data on the involvement of epigenetic mechanisms in Al-induced neurotoxicity, especially AD-type pathology. Existing data demonstrate that Al exposure induces disruption in DNA methylation, histone modifications, and non-coding RNA expression in brains. Alterations in DNA methylation following Al exposure were shown to be mediated by changes in expression and activity of DNA methyltransferases (DNMTs) and ten-eleven translocation proteins (TETs). Al exposure was shown to reduce histone acetylation by up-regulating expression of histone deacetylases (HDACs) and impair histone methylation, ultimately contributing to down-regulation of brain-derived neurotrophic factor (BDNF) expression and activation of nuclear factor κB (NF-κB) signaling. Neurotoxic effects of Al exposure were also associated with aberrant expression of non-coding RNAs, especially microRNAs (miR). Al-induced patterns of miR expression were involved in development of AD-type pathology by increasing amyloid β (Aβ) production through up-regulation of Aβ precursor protein (APP) and β secretase (BACE1) expression (down-regulation of miR-29a/b, miR-101, miR-124, and Let-7c expression), increasing in neuroinflammation through NF-κB signaling (up-regulation of miR-9, miR-125b, miR-128, and 146a), as well as modulating other signaling pathways. Furthermore, reduced global DNA methylation, altered histone modification, and aberrant miRNA expression were associated with cognitive decline in Al-exposed subjects. However, further studies are required to evaluate the contribution of epigenetic mechanisms to Al-induced neurotoxicity and/or AD development.

AMP-activated protein kinase mediates (-)-epigallocatechin-3-gallate (EGCG) to promote lipid synthesis in mastitis cows

Mastitis, a serious threat to the health and milk production function of dairy cows decreases milk quality. Blood from three healthy cows and three mastitis cows were collected in this study and their transcriptome was sequenced using the Illumina HiSeq platform. Differentially expressed genes (DEGs) were screened according to the |log2FoldChange| > 1 and P-value < 0.05 criteria. Pathway enrichment and functional annotation were performed through KEGG and GO analyses. Finally, the mechanism of the AMP-activated protein kinase (AMPK) mediation of (-)-epigallocatechin-3-gallate (EGCG) to promote lipid metabolism in mastitis cows was analyzed in bovine mammary epithelial cells (BMECs). Transcriptome analysis revealed a total of 825 DEGs, with 474 genes showing increased expression and 351 genes showing decreased expression. The KEGG analysis of DEGs revealed that they were mainly linked to tumour necrosis factor, nuclear factor-κB signalling pathway, and lipid metabolism-related signalling pathway, whereas GO functional annotation found that DEGs were enriched in threonine and methionine kinase activity, cellular metabolic processes, and cytoplasm. AMPK expression, which is involved in several lipid metabolism pathways, was downregulated in mastitis cows. The results of in vitro experiments showed that the inhibition of AMPK promoted the expression of lipid synthesis genes in lipopolysaccharide-induced BMECs and that EGCG could promote lipid synthesis by decreasing the expression of AMPK and downregulating the expression of inflammatory factors in inflammatory BMECs. In conclusion, our study demonstrated that AMPK mediated EGCG to inhabit of inflammatory responses and promote of lipid synthesis in inflammatory BMECs.

Therapeutic Potential of Insect Defensin DLP4 Against Staphylococcus hyicus-Infected Piglet Exudative Epidermitis

Background/Objectives: The emergence of resistance to Staphylococcus hyicus (S. hyicus), the major cause of exudative epidermatitis (EE) in piglets, has led to the need for new antimicrobial agents. The study aimed to evaluate the potential efficacy of the insect defensin DLP4 against EE in piglets caused by clinically isolated S. hyicus ACCC 61734. Methods and Results: DLP4 showed strong antibacterial activity against S. hyicus ACCC 61734 (minimum inhibitory concentration, MIC: 0.92 μM, median effect concentration, EC50: 3.158 μM). DLP4 could effectively inhibit the formation of S. hyicus early biofilm with an inhibition rate of 95.10–98.34% and eradicate mature biofilm with a clearance rate of 82.09–86.41%, which was significantly superior to that of ceftriaxone sodium (CRO). Meanwhile, DLP4 could efficiently inhibit bacteria in early and mature biofilm, killing up to 95.3% of bacteria in early biofilm and 87.2–90.3% of bacteria in mature biofilm. The results showed that DLP4 could be effective in alleviating the clinical symptoms of EE by down-regulating the nuclear factor κB (NF-κB) signaling pathway, balancing cytokines, inhibiting bacterial proliferation, and reducing organ tissue damage. Conclusions: This study firstly demonstrated the potential efficacy of DLP4 against EE caused by S. hyicus ACCC 61734 infection in piglets, which may be used as an alternative to antibiotics in treating EE.

Vaginal lactobacilli produce anti-inflammatory β-carboline compounds.

The optimal vaginal microbiome is a Lactobacillus-dominant community. Apart from Lactobacillus iners, the presence of Lactobacillus species is associated with reduced vaginal inflammation and reduced levels of pro-inflammatory cytokines. Loss of Lactobacillus-dominance is associated with inflammatory conditions, such as bacterial vaginosis (BV). We have identified that Lactobacillus crispatus, a key vaginal bacterial species, produces a family of β-carboline compounds with anti-inflammatory activity. These compounds suppress nuclear factor κB (NF-κB) and interferon (IFN) signaling downstream of multiple pattern recognition receptors in primary human cells and significantly dampen type I IFN receptor (IFNAR) activation in monocytes. Topical application of an anti-inflammatory β-carboline compound, perlolyrine, was sufficient to significantly reduce vaginal inflammation in a mouse model of genital herpes infection. These compounds are enriched in cervicovaginal lavage (CVL) of healthy people compared with people with BV. This study identifies a family of compounds by which vaginal lactobacilli mediate host immune homeostasis and highlights a potential therapeutic avenue for vaginal inflammation.

Mycobacterium tuberculosis Suppresses Inflammatory Responses in Host through Its Cholesterol Metabolites.

Cholesterol is a key carbon source for Mycobacterium tuberculosis (Mtb) survival and persistence within macrophages. However, little is known about the role of cholesterol metabolism by Mtb in host-Mtb interplay. Here, we report the immune suppression mediated by Mtb's cholesterol metabolites. Conducting the cholesterol metabolic profiling and loss-of-function experiments, we show that the cholesterol oxidation products catalyzed by a thiolase FadA5 from Mtb H37Ra, 4-androstenedione (AD), and its derivant 1,4-androstenedione (ADD) inhibit the expression of pro-inflammatory cytokines and thus promote bacterial survival in bone marrow-derived macrophages (BMDMs). Our time-resolved fluorescence resonance energy transfer (TR-FRET)-based screening further identifies the nuclear receptor LXRα as the target of ADD. Activation of LXRα via ADD impedes the nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPK) signaling and reduces cholesterol accumulation in lipid rafts upon TLR4 simulation, thereby compromising the inflammatory responses. Our findings provide the evidence that Mtb could suppress the host immunity through its cholesterol metabolic enzyme and products, which are potential targets for screening novel anti-tuberculosis (TB) agents.

Cellular and Molecular Mechanisms of Hypertrophy of Ligamentum Flavum.

Hypertrophy of the ligamentum flavum (HLF) is a common contributor to lumbar spinal stenosis (LSS). Fibrosis is a core pathological factor of HLF resulting in degenerative LSS and associated low back pain. Although progress has been made in HLF research, the specific molecular mechanisms that promote HLF remain to be defined. The molecular factors involved in the onset of HLF include increases in inflammatory cytokines such as transforming growth factor (TGF)-β, matrix metalloproteinases, and pro-fibrotic growth factors. In this review, we discuss the current understanding of the mechanisms involved in HLF with a particular emphasis on aging and mechanical stress. We also discuss in detail how several pathomechanisms such as fibrosis, proliferation and apoptosis, macrophage infiltration, and autophagy, in addition to several molecular pathways involving TGF-β1, mitogen-activated protein kinase (MAPKs), and nuclear factor-κB (NF-κB) signaling, PI3K/AKT signaling, Wnt signaling, micro-RNAs, extracellular matrix proteins, reactive oxygen species (ROS), etc. are involved in fibrosis leading to HLF. We also present a summary of the current advancements in preclinical animal models for HLF research. In addition, we update the current and potential therapeutic targets/agents against HLF. An improved understanding of the molecular processes behind HLF and a novel animal model are key to developing effective LSS prevention and treatment strategies.

Actinidia chinensis polysaccharide interferes with the epithelial-mesenchymal transition of gastric cancer by regulating the nuclear transcription factor-κB pathway to inhibit invasion and metastasis.

To investigate the mechanisms of the effect of Actinidia chinensis polysaccharide (ACPS) on the invasion and metastasis of gastric cancer cells. BGC-823-Luc gastric cancer cells stably transfected with a luciferase gene were used to establish an insitutransplanted tumor mouse model. A live mouse imaging system was used to observe tumor growth, and hematoxylin and eosin staining was applied to analyze tissue histopathology. Transwell and scratch wound assays were performed to examine the invasive and migratory ability of BGC-823 cells. Immunofluorescence, confocal microscopy, immunohistochemistry, and Western blot assays were used to analyze the expressions of the nuclear transcription factor-κB (NF-κB) signaling pathway and epithelial-mesenchymal transition (EMT)-related proteins. ACPS significantly inhibited the growth of subcutaneously transplanted BGC-823-Luc gastric cancer tumors in nude mice and reduced inflammatory cell infiltration in tumor tissues. ACPS inhibited Epidermal Growth Factor-induced invasion, migration, and morphological changes in the cytoskeleton of BGC-823 cells. ACPS inhibited gastric cancer EMT and decreased the expression of matrix metallopeptidase 9, N-cadherin and p-NF-κB p65 in transplanted tumor tissues. ACPS inhibited the expression of matrix metalloproteinases and vascular adhesion factors in BGC-823 cells, promoted p65-NF-κB nuclear translocation, and regulated proteins associated with the NF-κB p65 pathway. ACPS inhibited gastric cancer invasion and metastasis both in vivo and in vitro, which evidenced the inhibition of gastric cancer EMT viaregulating the NF-κB inflammatory pathway.

Fusobacterium Nucleatum Promotes Microsatellite Instability in Colorectal Carcinoma Through Up-regulation of miRNA-155-5p-Targeted Inhibition of MSH6 via the TLR4/NF-κB Signaling Pathway.

Fusobacterium nucleatum (Fn) is significantly associated with poor prognosis in colorectal carcinoma (CRC), however, mechanisms of Fn in DNA mismatch repair (MMR) and microsatellite instability (MSI) in CRC have not been fully elucidated. Clinical samples are collected to analyze the relationship between Fn abundance and microsatellite stability. Tumor cells are treated with Fn to detect the expression of proteins related to toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (Myd88), mutS homolog 6 (MSH6), and nuclear factor-κB (NF-κB) signaling pathways, respectively. Combined with the prediction results from TargetScan, the regulatory role of microRNA upstream of MSH6 is demonstrated. The effect of this regulatory axis on CRC development is demonstrated using a nude mouse tumor model. Compared with microsatellite stability (MSS)-type CRC patients, MSI-type showed higher Fn abundance. Fn treatment of CRC cells activated TLR4/Myd88/NF-κB signaling pathway, transcriptionally activating miRNA-155-5p expression, thereby negatively regulating MSH6. Fn treatment accelerated the malignant progression of CRC in mice, and this process is inhibited by miRNA-155-5p antagomir. Fn in CRC upregulated miRNA-155-5p by activating TLR4/NF-κB signaling to inhibit MSH6, and this regulatory pathway may affect MSS of cancer cells.

PP2 suppresses proliferation and migration of C6 Glioma and MDA-MB-231 cells by targeting both fibroblast growth factor receptor 1 and Src

Fibroblast growth factor (FGF) is involved in the progression of glioma, a most common type of brain tumor, and breast tumors. In this study, we aim to evaluate the effects of the inhibitor PP2 on cell proliferation and migration in glioma and breast tumor cells, and to characterize the molecular mechanisms involved in these processes. The inhibitory effect of PP2 on the tumorigenic potential of C6 glioma and MDA-MB-231 cells was examined by proliferation, migration, and invasion assays, and apoptotic analysis. The molecular mechanism behind the anti-glioma activity of PP2 was investigated by immunoblotting, immunoprecipitation, phosphoprotein assay, cellular thermal shift assay (CETSA), and molecular docking modeling. PP2 suppressed the proliferation and migration of C6 glioma and MDA-MB-231 cells via FGF2. Moreover, PP2 directly blocked the enzyme activity of FGF receptor 1 (FGFR1) and Src, subsequently affecting the nuclear factor-κB and activator protein-1 signaling pathways. CETSA analysis and the docking model indicated that the TK1 domains (Val 492 ad Glu 486) of FGFR2 could be binding sites of PP2. Collectively, therefore, our findings suggest that PP2 mediates antitumor effects by targeting both FGFR1 and Src and may have applications as a therapeutic inhibitor for the treatment of glioma.

The role of 2ʹ–5ʹ-oligoadenylate synthase-like protein (OASL1) in biliary and hepatotoxin-induced liver injury in mice

Following an injury, the liver embarks on a process that drives the accumulation and reformation of the extracellular matrix, leading to hepatic fibrosis. Type I interferons (IFNs), including IFN-α and IFN-β, play a crucial role in averting chronic liver injury through the activation of IFN-stimulated genes (ISGs), which are instrumental in sculpting adaptive immunity. The role of 2ʹ–5ʹ-oligoadenylate synthase-like protein 1 (OASL1), an antiviral ISG, in the context of liver fibrosis remains to be elucidated. To elicit liver fibrosis, a diet containing 0.1% diethoxycarbonyl-1,4-dihydrocollidine (DDC) and carbon tetrachloride (CCl4) were employed to induce cholestatic- and hepatotoxin-mediated liver fibrosis, respectively. Histological analyses of both models revealed that OASL1−/− mice exhibited reduced liver damage and, consequently, expressed lower levels of fibrotic mediators, notably α-smooth muscle actin. OASL1−/− mice demonstrated significantly elevated IFN-α and IFN-β mRNA levels, regulated by the IFN regulatory factor 7 (IRF7). Additionally, OASL1−/− ameliorated chronic liver fibrosis through the modulation of nuclear factor-κB (NF-κB) signaling. The effect of OASL1 on type I IFN production in acute liver damage was further explored and OASL1−/− mice consistently showed lower alanine transaminase levels and pro-inflammatory cytokines, but IFN-α and IFN-β mRNA levels were upregulated, leading to amelioration of acute liver injury. Additionally, the study discovered that F4/80-positive cells were observed more frequently in OASL1−/− CCl4 acutely treated mice. This implies that there is a significant synergy in the function of macrophages and OASL1 deficiency. These results demonstrate that in instances of liver injury, OASL1 inhibits the production of type I IFN by modulating the NF-κB signaling pathway, thereby worsening disease.

The alpha2-adrenoceptor agonist clonidine protects against hypoxic-ischemic brain damage in neonatal mice through the Nrf2/NF-κB signaling pathway

Neonatal hypoxic-ischemic brain damage (HIBD) is a severe condition closely associated with neuroinflammation and oxidative stress. Clonidine, a selective α2-adrenergic receptor agonist, is known for its anti-inflammatory and antioxidant properties. Despite these recognized therapeutic benefits, the exact mechanisms by which clonidine exerts its effects in the context of HIBD are not fully understood. This study was designed to thoroughly investigate the impact of clonidine on HIBD-induced neuronal injury and to clarify its underlying mechanism of action. We employed a neonatal mouse model of HIBD to meticulously assess the effects of clonidine on neuronal injury, apoptosis, inflammation, and oxidative stress markers. In addition, we conducted extensive in vitro studies to evaluate the neuroprotective effects of clonidine on primary hippocampal neuronal cells, utilizing advanced techniques such as the Cell Counting Kit-8 (CCK-8), flow cytometry, enzyme-linked immunosorbent assay (ELISA), immunofluorescence assay, and western blotting. Furthermore, we explored the regulatory effects of clonidine on the nuclear factor erythroid 2-related factor (Nrf2)/nuclear factor-κB (NF-κB) signaling pathway through a combination of in vivo and in vitro experiments. The results showed that clonidine significantly reduced cerebral infarction, neuronal damage, and apoptosis in HIBD mice. It also alleviated neuroinflammation and oxidative stress, improved cell viability, and reduced neuronal injury following oxygen-glucose deprivation/reoxygenation (OGD/R). The neuroprotective effects of clonidine were linked to the activation of the Nrf2/heme oxygenase-1 (HO-1) pathway and the inhibition of the NF-κB pathway. Overall, clonidine exhibited neuroprotective properties in HIBD by reducing neuroinflammation and oxidative stress, likely through the modulation of the Nrf2/NF-κB signaling pathway.

Nuclear Factor Kappa B: A Nobel Therapeutic Target of FlavonoidsAgainst Parkinson's Disease.

Parkinson's disease (PD), the most common brain-related neurodegenerative disorder, is comprised of several pathophysiological mechanisms, such as mitochondrial dysfunction, neuroinflammation, aggregation of misfolded alpha-synuclein, and synaptic loss in the substantia nigra pars compacta region of the midbrain. Misfolded alpha-synuclein, originating from damaged neurons, triggers a series of signaling pathways in both glial and neuronal cells. Activation of such events results in the production and expression of several proinflammatory cytokines via the activation of the nuclear factor κB (NF-κB) signaling pathway. Consequently, this cascade of events worsens the neurodegenerative processes, particularly in conditions, such as PD and synucleinopathies. Microglia, astrocytes, and neurons are just a few of the many cells and tissues that express the NF-κB family of inducible types of transcription factors. The dual role of NF-κB activation can be crucial for neuronal survival, although the classical NF-κB pathway is important for controlling the generation of inflammatory mediators during neuroinflammation. Modulating NF-κB-associated pathways through the selective action of several agents holds promise for mitigating dopaminergic neuronal degeneration and PD. Several naturally occurring compounds in medicinal plants can be an effective treatment option in attenuating PD-associated dopaminergic neuronal loss via selectively modifying the NF-κB-mediated signaling pathways. Recently, flavonoids have gained notable attention from researchers because of their remarkable anti-neuroinflammatory activity and significant antioxidant properties in numerous neurodegenerative disorders, including PD. Several subclasses of flavonoids, including flavones, flavonols, isoflavones, and anthocyanins, have been evaluated for neuroprotective effects against in vitro and in vivo models of PD. In this aspect, the present review highlights the pathological role of NF-κB in the progression of PD and investigates the therapeutic potential of natural flavonoids targeting the NF-κB signaling pathway for the prevention and management of PD-like manifestations with a comprehensive list for further reference. Available facts strongly support that bioactive flavonoids could be considered in food and/or as lead pharmacophores for the treatment of neuroinflammation-mediated PD. Furthermore, natural flavonoids having potent pharmacological properties could be helpful in enhancing the economy of countries that cultivate medicinal plants yielding bioactive flavonoids on a large scale.

γ-Aminobutyric acid alleviates litchi thaumatin-like protein-induced inflammation and reduces gut microbial translocation

Previous research reported litchi thaumatin-like protein (LcTLP) could lead to inflammation, which is a factor causing the adverse reactions after excessive intake of litchi. As a main amino acid in litchi pulp, γ-aminobutyric acid (GABA) was found with anti-inflammatory effect. Therefore, this study aimed to investigate the effects of GABA on LcTLP-induced inflammation through RAW264.7 macrophages and C57BL mice models. In vitro study showed GABA could effectively regulate the level of inflammatory cytokines (interleukin (IL)-1β, IL-6, IL-10, and prostaglandin E2) and Ca2+ in cells, and inhibit the phosphorylation of p65, IκB, p38, c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK). These results indicate GABA alleviated inflammation through nuclear factor-κB and mitogen-activated protein kinase pathways signaling pathways. In vivo experiment was performed to verify the anti-inflammatory effect of GABA, and the results demonstrated that GABA reduced the inflammation and oxidative stress in the liver of LcTLP-treated mice, as it down-regulated the pro-inflammatory cytokines, malondialdehyde, aspartate transferase, and alanine transaminase. The relative expression of phosphorylated p38, JNK and ERK in mice liver with GABA treatment were reduced to 65 %, 39 % and 80 % of the control group, respectively. Furthermore, GABA treatment enriched probiotic bacteria and decreased pathogenic bacteria in mice gut, which reveals GABA could effectively reduce the translocation of gut microbiota.

Protective effect of astaxanthin on chronic prostatitis/chronic pelvic pain syndrome in rat through modulating NF-κB signaling pathway.

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a common male urological disease characterized by chronic pelvic pain and various discomforts. Astaxanthin (AST) has multiple functions, including anti-inflammatory property, but it is unclear whether AST plays a key role in CP/CPPS and how it works. This study aimed to investigate the protective effect of AST on CP/CPPS in rats and the underlying mechanism. A CP/CPPS rat model was induced by intraprostatic injection of carrageenan and the blood specimens and prostates were harvested for further research after oral administration of AST for 4 weeks. Tactile allodynia test showed that AST ameliorated chronic pelvic pain in a dose-depended manner. In addition, histological evaluation indicated that AST alleviated CP/CPPS rat prostate histological inflammation. Meanwhile, AST suppressed the expression of proinflammatory cytokines, including interleukin-1β (IL-1β), IL-6, IL-8, and tumor necrosis factor-α (TNF-α). Besides, AST inhibited the activities of prostaglandin E2 (PGE2) and cyclooxygenase 2 (COX2). Furthermore, AST decreased the activation of the nuclear factor-κB (NF-κB) signaling pathway. Our study has shown that AST exerts an anti-inflammatory and protective effect against CP/CPPS and the function is mediated at least through the suppression of NF-κB signaling pathway. These results provide evidence of AST as the potential agents for the treatment of CP/CPPS.

E3 ubiquitin ligase ANKIB1 attenuates antiviral immune responses by promoting K48-linked polyubiquitination of MAVS

Upon sensing cytosolic viral RNA, retinoic acid-inducible gene-I-like receptors (RLRs) interact with mitochondrial antiviral signaling proteins (MAVSs) to activate IRF3 and nuclear factor κB (NF-κB) signaling, initiating innate immune responses. Thus, RLR activation plays a vital role in the removal of invasive RNA viruses while maintaining immune homeostasis. However, inadequate or excessive activation of immunity can cause harm and can even lead to lethal consequences. In this study, we identify an E3 ligase, ankyrin repeat and IBR domain containing 1 (ANKIB1), which suppresses RLR signaling via MAVS. ANKIB1 binds to MAVS to enhance K48-linked polyubiquitination with K311R, causing proteasomal degradation of MAVS. Deficiency of ANKIB1 significantly increases the RLR-mediated production of type I interferon (IFN) along with pro-inflammatory factors. Consequently, ANKIB1 deficiency remarkably increases antiviral immunity and decreases viral replication invivo. Therefore, we reveal that ANKIB1 restricts RLR-induced innate immune activation, indicating its potential role as a therapeutic target for viral infections.

Distinct clinical outcomes and biological features of specific KRAS mutants in human pancreatic cancer

KRAS mutations in pancreatic ductal adenocarcinoma (PDAC) are suggested to vary in oncogenicity but the implications for human patients have not been explored in depth. We examined 1,360 consecutive PDAC patients undergoing surgical resection and find that KRASG12R mutations are enriched in early-stage (stage I) disease, owing not to smaller tumor size but increased node-negativity. KRASG12R tumors are associated with decreased distant recurrence and improved survival as compared to KRASG12D. To understand the biological underpinnings, we performed spatial profiling of 20 patients and bulk RNA-sequencing of 100 tumors, finding enhanced oncogenic signaling and epithelial-mesenchymal transition (EMT) in KRASG12D and increased nuclear factor κB (NF-κB) signaling in KRASG12R tumors. Orthogonal studies of mouse KrasG12R PDAC organoids show decreased migration and improved survival in orthotopic models. KRAS alterations in PDAC are thus associated with distinct presentation, clinical outcomes, and biological behavior, highlighting the prognostic value of mutational analysis and the importance of articulating mutation-specific PDAC biology.

Nuciferine inhibits TLR4/NF-κB/MAPK signaling axis and alleviates adjuvant-induced arthritis in rats

Rheumatoid arthritis is an inflammatory condition primarily affecting the joints. Nuciferine (NCF), a key bioactive aporphine alkaloid biosynthesized in lotus leaves, exhibits promising anti-inflammatory and antioxidant properties. In this study, we investigated whether NCF could alleviate inflammatory arthritis conditions in a complete Freund's adjuvant (CFA)-mediated arthritis model in rats. The arthritis model was established through intradermal injection of CFA (100 μL) in the sub-plantar region of the right hind paw. The arthritic animals were treated orally with NCF at 5 and 10 mg/kg and indomethacin (Indo) at 5 mg/kg body weight as reference control. NCF treatment remarkably alleviated inflammatory joint swelling and arthritic index. The radiological and histological analysis revealed evidence of the beneficial effects of NCF. NCF treatment decreased the content of pro-inflammatory cytokines (TNF-α and IL-1β) and myeloperoxidase (MPO) activity and restored the anti-inflammatory cytokine (IL-10) in the paw joints. The serum levels of pro-inflammatory cytokines were also markedly reduced in the NCF (10 mg/kg) treatment group. Moreover, the arthritis-induced inflammatory mediators, including cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS) and the toll-like receptor (TLR)-4, mitogen-activated protein kinase (MAPK), and nuclear factor-κB (NF-κB) signaling proteins were substantially decreased in the NCF treatment groups. NCF treatment also restored the antioxidant defense enzymes and abrogated lipid peroxidation in the paw tissue. Our findings strongly suggest that NCF is a promising therapeutic molecule for rheumatoid arthritis, inspiring further research, and development in this area.

Moxibustion with seed-size moxa cones alleviates colonic injury in mice with ulcerative colitis by regulating TLR4/MyD88/NF-κB signaling pathway.

To observe the effect of moxibustion with seed-size moxa cones on the Toll-like receptor 4(TLR4)/myeloid differentiation factor 88(MyD88)/nuclear transcription factor-κB(NF-κB) signaling pathway in mice with ulcerative colitis(UC), so as to explore the therapeutic mechanism of moxibustion with seed-size moxa cones on colonic injury in UC. Forty male C57BL/6 mice were randomly divided into blank group, model group, moxibustion group, and western medicine group, with 10 mice in each group. The UC mouse model was established by 3% DSS solution by free drinking for 7 consecutive days. Mice in the moxibustion group were treated with seed-size moxa cones at "Zhongwan"(CV12), "Tianshu"(ST25) and "Shangjuxu"(ST37), 3 moxa cones per point, with each cone applied for approximately 30 s, while mice in the western medicine group were orally administered with 300 mg/kg mesalazine solution, which were both conducted once a day for 7 consecutive days. The general condition of mice was observed every 2 days, and the disease activity index (DAI) score was calculated. HE staining was used to observe the morphology of colonic tissue in mice. ELISA was used to detect the serum interleukin(IL)-1β, tumor necrosis factor(TNF)-α, IL-6, and IL-8 contents. Immunohistochemistry was used to detect the positive expression of TLR4 and MyD88 in colonic tissue of mice. Real-time fluorescence quantitative PCR was used to detect the expression levels of TLR4, MyD88, and NF-κB p65 mRNAs in colonic tissue. Compared with the blank group, varying degrees of soft or watery stools were observed, colon length and body weight were decreased(P<0.01) in mice of the model group, while DAI score, colon weight index, mucosal damage score, colonic pathological score, serum IL-1β, TNF-α, IL-6, and IL-8 contents, positive expressions of TLR4 and MyD88, and TLR4, MyD88, and NF-κB p65 mRNA expressions in colonic tissue were increased(P<0.01). Compared with the model group, improved fecal characteristics were observed, colon length and body weight were increased(P<0.01) in mice of the moxibustion group and western medicine group, while DAI scores, colon weight indexes, mucosal damage scores, colonic pathological score, serum contents of IL-1β, TNF-α, IL-6, and IL-8, positive expressions of TLR4 and MyD88, and TLR4, MyD88, and NF-κB p65 mRNA expressions in colonic tissue were decreased(P<0.01, P<0.05). There was no significant difference in the above indicators between the moxibustion group and the western medicine group. Moxibustion with seed-size moxa cones may alleviate colonic injury in UC mice by regulating the TLR4/MyD88/NF-κB signaling pathway and reducing the release of inflammatory factors.

Inhibiting CD44-ICD Attenuates LPS-Induced Initiation of Hepatic Inflammation in Septic Mice.

Sepsis is a severe condition induced by microbial infection. It elicits a systemic inflammatory response, leading to multi-organ failure, and the liver, as a scavenger, plays a significant role in this process. Controlling hepatic inflammation and maintaining liver function is crucial in managing sepsis. CD44-ICD, as a CD44 signal transductor, is involved in multiple inflammatory responses. However, the role of CD44-ICD in lipopolysaccharide (LPS)-induced hepatic inflammation has not been investigated. Therefore, we aimed to examine whether CD44-ICD initiates hepatic inflammation in septic mice. We induced hepatic inflammation in mice by administering LPS. DAPT, a CD44-ICD inhibitor, was given to mice or Chang cells 30 min or 1 h before LPS administration (10 mg/kg, i.p., or 100 ng/mL, respectively). Inhibition of CD44-ICD decreased the level of aspartate aminotransferase (AST), alanine aminotransferase (ALT), hepatic necrosis, inflammatory cell infiltration, interleukin (IL)-1β, inducible NO synthase (iNOS), nitric oxide (NO) production, nuclear factor (NF)κB signaling pathway proteins, and CD44 expression in mice. CD44-ICD inhibition also decreased IL-1β and CD44 expression levels in Chang cells. CD44-ICD may be a primary regulatory function in CD44-associated LPS-induced initiation of hepatic inflammation in mice.

Effect of the immunoregulation activity of a pectin polysaccharide from Saussurea laniceps petals on macrophage polarization

Saussurea laniceps is a traditional medicinal herb. In our previous study, a pectin polysaccharide, SLP-4, was isolated from the petals of S. laniceps. In this study, the immunomodulatory activity of SLP-4 was studied by analyzing its effects on macrophage (RAW 264.7 cells) polarization. The immunomodulatory activity assays indicated that SLP-4 could significantly enhance the pinocytic and phagocytic capacity and promote the expression and secretion of cytotoxic molecules (nitric oxide, increased by 6.4 times when the SLP-4 concentration was 800 μg/mL) and cytokines (tumor necrosis factor-α and interleukin-6 increased by 7.7 and 11.9 times, respectively) in original macrophage. The possible mechanism could be attributed to the activation of the mitogen-activated protein kinase and nuclear factor-κB signaling pathways through Toll-like receptors 2 and 4. Moreover, SLP-4 significantly induced M1 polarization of original macrophages and transferred macrophages from M2 to M1, but had little effect on the conversion of M1 macrophages into M2 phenotype. Overall, these results demonstrate the potential of SLP-4 as an attractive immunomodulating functional supplement.