Engeletin attenuates the inflammatory response via inhibiting TLR4-NFκB signaling pathway in Crohn's disease-like colitis.

ETHNOPHARMACOLOGICAL RELEVANCE: Smilax glabra rhizome has a long history been used for clinical purposes in traditional Chinese medicinal for treating various inflammatory conditions. Engeletin1 (ENG) is one of the most abundant bioactive compounds found in Smilax glabra rhizome, with anti-inflammatory, antioxidant, and ulcer-preventing activities. AIM OF THE STUDY: The purpose of this study was to investigate the ability of ENG to alleviate inflammatory symptoms and improve epithelial barrier integrity utilize a 2,4,6-trinitrobenzene sulfonic acid2 (TNBS)-induced murine model in Crohn's disease3 (CD)-like colitis, and to characterize the underlying anti-inflammatory mechanisms of action. MATERIALS AND METHODS: A colitis model was established in BALB/c mice and treated with ENG for 7 days. RAW264.7 macrophages were pre-treated with ENG and lipopolysaccharide4 (LPS) stimulation. The mice's weight and colon length were assessed. qPCR and Western blotting were used to analyze gene expression and TLR4-NFκB pathway. Flow cytometry was used to analyze the polarization states of the macrophages. RESULTS: Treatment with ENG was sufficient to significantly alleviate symptoms of inflammation and colonic epithelial barrier integrity in treated mice. Significant inhibition of TNF-α, IL-1ß, and IL-6 expression was observed following ENG treatment in vivo and in vitro. ENG was also determined to be capable of inhibiting the expression of iNOS and CD86, inhibited M1 macrophage polarization in vitro, as well as the TLR4-NFκB signaling pathway. Molecular docking showed a highly stable binding between ENG and TLR4. CONCLUSION: ENG has been proven to alleviate inflammation and ameliorate the damage of epithelial barrier in CD-like colitis. ENG also suppressed the M1 macrophages polarization and the inhibited inflammatory cytokines. TLR4-NFκB signaling pathway, especially TLR4, may be the target of ENG. These data offer a new insight into the therapeutic mechanisms of ENG.

MiR-24 regulates obstructive pulmonary disease in rats via S100A8.

PURPOSE: Chronic obstructive pulmonary disease (COPD) is a persistent inflammatory disorder characterized by minor airway inflammation and emphysema involving various cell types and cytokines. MicroRNAs (miRNAs) have emerged as critical regulators in the pathogenesis of lung diseases. This study investigates the impact of microRNA-24 (miR-24) on airway inflammatory responses in a rat model of COPD. MATERIALS AND METHODS: The model was established by combining cigarette smoke exposure and lipopolysaccharide stimulation, and rat lung tissues were transfected with adeno-associated viruses overexpressing miR-24. Pathological changes in the lung were assessed using hematoxylin and eosin staining. Levels of pro-inflammatory cytokines, including tumor necrosis factor-alpha, interleukin-6, and interleukin-8, were measured using enzyme-linked immunosorbent assay. Expression of miR-24 and S100A8 was detected through quantitative reverse transcription PCR, while protein levels of S100A8, Toll-like receptor 4 (TLR4), and myeloid differentiation primary response 88 (MyD88) were assessed using western blotting. Bioinformatics analysis and dual-luciferase reporter assay were performed to determine the relationship between S100A8 and miR-24. RESULTS: The results demonstrated the downregulation of miR-24 in rats with COPD, and its overexpression resulted in a significant decrease in S1008 mRNA levels. Additionally, the protein level of S100A8 was significantly increased in the lung tissues of COPD rats. The upregulation of miR-24, however, not only inhibited the protein expression of S100A8, TLR4, and MyD88 in lung tissues but also reduced the release of pro-inflammatory cytokines in the plasma and bronchoalveolar lavage fluid, thereby attenuating inflammatory responses and pathological injuries in the lung. CONCLUSIONS: Our data suggest that miR-24 attenuates airway inflammatory responses in COPD by inhibiting the TLR4/MyD88 pathway via targeting S100A8.

Elevated levels of damage-associated molecular patterns HMGB1 and S100A8/A9 coupled with toll-like receptor-triggered monocyte activation are associated with inflammation in patients with myelofibrosis.

Inflammation plays a pivotal role in the pathogenesis of primary and post-essential thrombocythemia or post-polycythemia vera myelofibrosis (MF) in close cooperation with the underlying molecular drivers. This inflammatory state is induced by a dynamic spectrum of inflammatory cytokines, although recent evidence points to the participation of additional soluble inflammatory mediators. Damage-associated molecular patterns (DAMPs) represent endogenous signals released upon cell death or damage which trigger a potent innate immune response. We assessed the contribution of two prototypical DAMPs, HMGB1 and S100A8/A9, to MF inflammation. Circulating HMGB1 and S100A8/A9 were elevated in MF patients in parallel to the degree of systemic inflammation and levels increased progressively during advanced disease stages. Patients with elevated DAMPs had higher frequency of adverse clinical features, such as anemia, and inferior survival, suggesting their contribution to disease progression. Monocytes, which are key players in MF inflammation, were identified as a source of S100A8/A9 but not HMGB1 release, while both DAMPs correlated with cell death parameters, such as serum LDH and cell-free DNA, indicating that passive release is an additional mechanism leading to increased DAMPs. HMGB1 and S100A8/A9 promote inflammation through binding to Toll-like receptor (TLR) 4, whereas the former also binds TLR2. Monocytes from MF patients were shown to be hyperactivated at baseline, as reflected by higher CD11b and tissue factor exposure and increased expression levels of proinflammatory cytokines IL-1ß and IL-6. Patient monocytes showed preserved TLR4 and TLR2 expression and were able to mount normal or even exacerbated functional responses and cytokine upregulation following stimulation of TLR4 and TLR2. Elevated levels of endogenous TLR ligands HMGB1 and S100A8/A9 coupled to the finding of preserved or hyperreactive TLR-triggered responses indicate that DAMPs may promote monocyte activation and cytokine production in MF, fueling inflammation. Plasma IL-1ß and IL-6 were elevated in MF and correlated with DAMPs levels, raising the possibility that DAMPs could contribute to cytokine generation in vivo. In conclusion, this study highlights that, in cooperation with classic proinflammatory cytokines, DAMPs represent additional inflammatory mediators that may participate in the generation of MF inflammatory state, potentially providing novel biomarkers of disease progression and new therapeutic targets.

Neuroprotective effect of Naochuxue prescription on intracerebral hemorrhage: inhibition of autophagy downregulating high mobility group box-1.

OBJECTIVE: To determine the molecular mechanisms underlying the neuroprotective effects of Naochuxue prescription (,NCXP) in rats with intracerebral hemorrhage (ICH). METHODS: Sprague-Dawley rats were injected with collagenase to generate ICH models, which were then randomly divided into six groups, including control, sham, model, and three intervention groups. The intervention groups received different doses of NCXP (0.13, 0.26, and 0.52 g/kg) daily for 10 d. High-performance liquid chromatography (HPLC) was used to analyze the chemical characteristics of NCXP. The neurobehavioral outcomes of the rats were evaluated using neurological deficit scores (Zea Longa 5) and the corner turn test. Pathomorphological changes in perihematomal tissues after ICH were observed using hematoxylin and eosin staining. Immunohistochemistry (IHC) was used to detect the inflammation expression of interleukin 6 (IL-6) and toll-like receptor 4 (TLR4). High mobility group box-1 (HMGB1), Beclin1, microtubule-associated protein 1 light chain 3 beta (LC3), and sequestosome 1 (p62) were detected using real-time quantitative polymerase chain reaction and Western blotting in perihematomal tissues. RESULTS: HPLC showed that the NCXP had good stability. Rats with ICH had severe neurological function deficits compared to the control group. IHC results showed that NCXP significantly downregulated the expression of the inflammatory proteins IL-6 and TLR4. ICH rats treated with NCXP showed less neurological injury than the model group, accompanied by a significantly decreased expression of HMGB1, Beclin1, and LC3 and an increased expression of p62. CONCLUSIONS: The neuroprotective effect of NCXP alleviated inflammation and autophagy possibly by downregulating HMGB1 expression. However, further research on the signaling pathways is required to verify this hypothesis.

Role of toll-like receptor 4/mutant myeloid differentiation primary response 88/nuclear factor kappa-B mediated inflammation in diabetes mellitus with Northwest dryness syndrome.

OBJECTIVE: To investigate the role of toll-like receptor 4 (TLR4)/mutant myeloid differentiation primary response 88 (MyD88)/nuclear factor kappa-B (NF-κB) signaling pathway-mediated inflammation in diabetes mellitus with Northwest dryness syndrome. METHODS: Rats were randomly divided into the normal control, type 2 diabetes (T2DM) model, Northwest dryness syndrome + T2DM (Northwest dryness), and simple internal dampness + T2DM (internal dampness) groups. Enzyme-linked immunosorbent assay was used to detect biochemical indexes and inflammatory factors. The histopathological observation was performed. Quantitative real-time polymerase chain reaction and Western blot analysis were used to detect the mRNA and protein expression levels, respectively. RESULTS: Compared with the T2DM group, the glycosylated hemoglobin A1c, insulin, glucose tolerance, the homeostasis model assessment of insulin resistance, tumor necrosis factor-α, interleukin 1ß, interleukin 16, malondialdehyde, blood lipid, alanine aminotransferase, and aspartate aminotransferase were significantly elevated in the internal dampness group. Their levels were significantly elevated in the Northwest dryness group than in the T2DM and internal dampness groups. The superoxide dismutase, glutathione peroxidase, liver glycogen, and organ-to-weight ratio were significantly declined in the internal dampness group and the Northwest dryness group than in the T2DM group. However, these levels were elevated in the Northwest dryness group than in the internal dampness group. Moreover, the mRNA expression levels of interferon regulatory factor 5 and NF-κB p65, and the protein expression levels of TLR4, MyD88, and NF-κB were significantly higher in the internal dampness and the Northwest dryness groups than the T2DM group. Additionally, the mRNA and protein levels were significantly higher in the Northwest dryness group than in the internal dampness group. CONCLUSION: Northwest dryness syndrome-mediated TLR4/MyD88/NF-κB pathway and chronic inflammation might be associated with the occurrence and development of T2DM.

The role of the S100A8/S100A9 in gastric tumor progression.

Gastric premalignant lesions can develop into cancer through multiple steps and inflammation plays a critical role. The aim of this study is to uncover the characteristics of macrophages and their gene expression in premalignant gastric lesions to identify novel biomarkers and potential targets for treatment. We used the computational algorithm CIBERSORT to estimate immune cell subsets present in gastric tissue. We applied WGCNA to identify inflammation-related modules and hub genes. Single-cell analysis was used to identify macrophage sub-clusters specific to pathology. In addition, the in-vitro experiment was performed to verify the mechanism of the key inflammatory factors in the growth of gastric cancer. WGCNA identified a module that was positively correlated with pathological changes and highly related to inflammation scores. Single-cell analysis revealed a macrophage subset, and we observed that S100A8 and S100A9 + macrophages made up a significantly higher proportion in early gastric cancer (EGC) tissues. Our functional enrichment analysis suggested that these macrophages may play a role in gastric tumorigenesis through the activation of the NFκB signaling pathway. In vitro experiments verified that S100A9 can promote the proliferation and migration of AGS cells through the TLR4-NFκB signaling pathway, and the S100A8/S100A9 inhibitor Paquinimod can inhibit their proliferation and migration. Our findings suggest that S100A8 and S100A9 + macrophages may activate the TLR4-NFκB signaling pathway to promote cell proliferation and migration leading to gastric tumor progression. Macrophages with high expression of S100A8/S100A9 are critical in the progression of gastric inflammation to cancer. Cytokine S100A9 can activate the TLR4-NFκB signaling pathway and promote the proliferation and migration of gastric adenocarcinoma cells.

Relationship between GTP binding protein RAB10, toll-like receptor 4, and nuclear factor kappa-B and prognosis in patients with breast cancer.

The objective of this study was to investigate the correlation between Rab10 (GTP binding protein RAB10), TLR4 (Toll-like receptor 4), and NF-κB (nuclear factor kappa-B) levels and therapeutic effects in peripheral blood of patients with breast cancer after surgery. The study included 160 patients with stage I-III breast cancer who underwent surgical treatment at our hospital's Department of Breast Surgery and Oncology between January 2021 and June 2021. ELISA was used to assess Rab10, TLR4, and NF-κB levels in peripheral blood. Based on their levels of Rab10, TLR4, and NF-κB in peripheral blood, participants were categorized into two groups: the low marker expression group (72 participants with relatively low expression of Rab10, TLR4, and NF-κB: Rab10<2.0ng/ml; TLR4<2.75ng/ml; NF-κB<3.5ng/ml) and the high marker expression group (88 participants with relatively high expression: Rab10 ≥ 2.0 ng/ml; TLR4 ≥ 2.75ng/ml; NF-κB ≥ 3.5ng/ml). All participants provided informed consent to participate the study. The baseline data of the two groups of patients, the presence or absence of lymph node metastasis and recurrence within 3 years after surgery, as well as the survival status within 3 years after surgery (including median overall survival and median progression-free survival) were statistically analyzed. The expressions of Rab10, TLR4, and NF-κB in the peripheral blood of patients were detected through enzyme-linked immunosorbent assay (ELISA). Kendall's tau-b correlation analysis was conducted to examine the relationship between the expressions of Rab10, TLR4, and NF-κB and the therapeutic effects outcomes. The levels of Rab10, TLR4, and NF - κ B in peripheral blood of the high marker expression group were higher than those of the low marker expression group (Rab10: 1.87 ± 0.18 vs. 3.15 ± 0.24 ng/ml; TLR4: 2.17 ± 0.20 vs. 3.26 ± 0.25 ng/ml); NF-κB: 2.68 ± 0.27 vs. 4.63 ± 0.30 ng/ml; P < 0.05). Analyzing the relationship between patient staging and Rab10, TLR4, and NF - κ B expression, the number of patients in high marker expression group III-IV increased compared to the low marker expression group (54.55% vs. 36.12%; P < 0.05), while the number of patients in high marker expression group I-II decreased compared to the low marker expression group (45.45% vs. 63.88%; P < 0.05). It was found that the number of patients with no recurrence or metastasis in the high marker expression group decreased compared to the low marker expression group (56.81% vs. 73.61%; P < 0.05), while the number of patients with recurrence or metastasis in the high marker expression group increased compared to the low marker expression group (43.19% vs. 26.39%; P < 0.05). The median overall survival and median progression free survival in the high marker expression group were shorter than those in the low marker expression group (median overall survival: 21.45 ± 2.68 months vs. 28.38 ± 3.44 months; median progression free survival: 15.25 ± 2.37 vs. 20.72 ± 2.58 months; P < 0.05). Kendall's tau-b correlation indicated a positive correlation between the expressions of Rab10, TLR4, and NF-κB and a poor therapeutic effects (P < 0.05), suggesting that elevated levels of Rab10, TLR4, and NF-κB may lead to a worsened therapeutic effects. There is a significant correlation between the presence of Rab10, TLR4, and NF-κB in the peripheral blood of breast cancer patients. Elevated levels of Rab10, TLR4, and NF-κB are linked to an increased risk of recurrence, metastasis, reduced overall survival, and progression-free survival.

Neuroprotective effects of all-trans-retinoic acid are mediated via downregulation of TLR4/NF-κB signaling in a rat model of middle cerebral artery occlusion.

OBJECTIVES: To determine the effects of all-trans-retinoic acid (ATRA) on the post-stroke inflammatory response and elucidate the underlying molecular mechanisms. METHODS: This animal experiment was conducted at Central Laboratory, the First Affiliated Hospital of Guangdong Pharmaceutical University, Guangzhou, China during 2020-2022. Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for 1.5 h, and treated with ATRA at 2 and 24 h after reperfusion. Neurological deficit scores on behavioral tests, and cerebral infarct volume, microglial polarization, and the expression levels of inflammatory cytokines and proteins associated with TLR4/NF-κB signaling were assessed. RESULTS: The ATRA administration reduced cerebral infarct volume and ameliorated neurological deficit scores in MCAO rats. Additionally, ATRA relieved cerebral edema and downregulated the secretion of proinflammatory cytokines after stroke. Finally, ATRA attenuated the polarization of the microglia toward the M1 phenotype and promoted the activation of the beneficial M2 phenotype; the underlying mechanism potentially involved the suppression of the TLR4/NF-κB signaling pathway. CONCLUSION: The ATRA treatment promoted functional recovery in an experimental model of ischemic stroke by attenuating neural inflammation. ATRA potentially modulated microglia-mediated neuroinflammation via the downregulation of the TLR4/NF-κB signaling pathway, which makes it a candidate treatment for post-stroke neuroinflammation.

Oxysterol binding protein regulates the resolution of TLR-induced cytokine production in macrophages.

Toll-like receptors (TLRs) on macrophages sense microbial components and trigger the production of numerous cytokines and chemokines that mediate the inflammatory response to infection. Although many of the components required for the activation of the TLR pathway have been identified, the mechanisms that appropriately regulate the magnitude and duration of the response and ultimately restore homeostasis are less well understood. Furthermore, a growing body of work indicates that TLR signaling reciprocally interacts with other fundamental cellular processes, including lipid metabolism but only a few specific molecular links between immune signaling and the macrophage lipidome have been studied in detail. Oxysterol-binding protein (Osbp) is the founding member of a family of lipid-binding proteins with diverse functions in lipid sensing, lipid transport, and cell signaling but its role in TLR responses is not well defined. Here, we demonstrate that altering the state of Osbp with its natural ligand, 25-hydroxycholesterol (25HC), or pharmacologically, sustains and thereby amplifies Tlr4-induced cytokine production in vitro and in vivo. CRISPR-induced knockdown of Osbp abrogates the ability of these ligands to sustain TLR responses. Lipidomic analysis suggested that the effect of Osbp on TLR signaling may be mediated by alterations in triglyceride production and treating cells with a Dgat1 inhibitor, which blocks triglyceride production and completely abrogates the effect of Osbp on TLR signaling. Thus, Osbp is a sterol sensor that transduces perturbations of the lipidome to modulate the resolution of macrophage inflammatory responses.

Blocking Brain Myeloid Differentiation Factor 2-Toll-like Receptor 4 Signaling Improves Cognition by Diminishing Brain Pathologies and Preserving Adult Hippocampal Neurogenesis in Obese Rats.

The myeloid differentiation factor 2 (MD-2)-toll-like receptor 4 (TLR4) signaling pathway has been linked to cognitive decline in obese rats. However, more research is required to fully understand the mechanistic role of MD-2-TLR4 signalling pathway in obese-related cognitive impairment. In this study, we used two novel MD-2 inhibitors-MAC28 (a mono-carbonyl analogue of curcumin 28) and 2i-10 (a cinnamamide-derivative compound)-to better comprehend the mechanistic role of the MD-2-TLR4 signalling pathway in obese-related cognitive impairment. A normal diet (ND) (n = 16) and a high-fat diet (HFD) (n = 64) were given to randomly divided groups of male Wistar rats for 16-weeks. At week 13, 2 types of vehicles were randomly administered to ND-fed and HFD-fed rats, whereas MAC28 (3-doses) and 2i-10 (3-doses) were randomly given to HFD-fed rats until week 16. HFD-fed rats developed obesity with metabolic disturbances, a variety of brain pathologies and cognitive decline. In obese rats, blocking the brain MD-2-TLR4 signalling pathway with MAC28 or 2i-10 improved cognition via reducing brain inflammation, neurodegeneration, microglial activation, dendritic spine loss, brain oxidative stress, as well as preserving adult hippocampal neurogenesis. Our findings highlight to better understand the role of MD-2-TLR4 signaling pathway in obese-related cognitive decline, and MD-2 could be a potential therapeutic target for brain pathologies and cognitive decline in obesity.

SARS-CoV-2 spike protein induces the cytokine release syndrome by stimulating T cells to produce more IL-2.

Introduction: Cytokine release syndrome (CRS) is one of the leading causes of mortality in patients with COVID-19 caused by the SARS-CoV-2 coronavirus. However, the mechanism of CRS induced by SARS-CoV-2 is vague. Methods: Using spike protein combined with IL-2, IFN-γ, and TNF-α to stimulate human peripheral blood mononuclear cells (PBMCs) to secrete CRS-related cytokines, the content of cytokines in the supernatant was detected, and the effects of NK, T, and monocytes were analyzed. Results: This study shows that dendritic cells loaded with spike protein of SARS-CoV-2 stimulate T cells to release much more interleukin-2 (IL-2,) which subsequently cooperates with spike protein to facilitate PBMCs to release IL-1ß, IL-6, and IL-8. These effects are achieved via IL-2 stimulation of NK cells to release tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ), as well as T cells to release IFN-γ Mechanistically, IFN-γ and TNF-α enhance the transcription of CD40, and the interaction of CD40 and its ligand stabilizes the membrane expression of toll-like receptor 4 (TLR4) that serves as a receptor of spike protein on the surface of monocytes. As a result, there is a constant interaction between spike protein and TLR4, leading to continuous activation of nuclear factor-κ-gene binding (NF-κB). Furthermore, TNF-α also activates NF-κB signaling in monocytes, which further cooperates with IFN-γ and spike protein to modulate NF-κB-dependent transcription of CRS-related inflammatory cytokines. Discussion: Targeting TNF-α/IFN-γ in combination with TLR4 may represent a promising therapeutic approach for alleviating CRS in individuals with COVID-19.

Aloperine Ameliorates Acetaminophen-Induced Acute Liver Injury through HMGB1/TLR4/NF-κB and NLRP3/Inflammasome Pathway.

Purpose: Aloperine (ALO), an alkaloid isolated from Sophora alopecuroides L., possesses multiple pharmacological activities and holds a promise potential for the treatment of various clinical conditions, including skin hypersensitivity, cancer, and inflammatory disorders. The purpose of this study was to investigate the role of ALO in acetaminophen (N-acetyl-para-aminophenol (APAP))-induced acute liver injury and its underlying mechanisms. Materials and Methods: An animal model of acute liver injury was induced by intraperitoneal injection of APAP (150 mg/kg). Prior to APAP injection, ALO (40 mg/kg) was administered daily for 7 consecutive days. Serum alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase levels were then measured using an automated chemical analyzer. Histopathological changes were evaluated using hematoxylin and eosin staining. Oxidative stress levels were measured by detecting superoxide dismutase (SOD), glutathione (GSH), and malondialdehyde (MDA). Pro-inflammatory cytokines were detected in serum and liver tissues using ELISA and quantitative real-time polymerase chain reaction (q-PCR). The expression of members of the HMGB1/TLR4/NF-κB signaling pathway and NLRP3 inflammasome were determined by Western blot and/or q-PCR. In addition, the expression and location of NLRP3, cleaved caspase-1, high-mobility group box 1 (HMGB1), and phosphorylated p65 (p-p65) were detected by immunofluorescence. Results: Pretreatment with ALO significantly protected mice from APAP-induced acute liver injury, with decreased MDA content, and significantly increased GSH and SOD activities. Furthermore, ALO pretreatment reduced the release of pro-inflammatory cytokines (IL-1ß and TNF-α) and decreased the expression of caspase-1, cleaved caspase-1, and NLRP3. In addition, ALO pretreatment also inhibited the activation of the HMGB1/TLR4/NF-κB signaling pathway. Conclusion: Taken together, ALO can ameliorate APAP-induced acute liver injury by inhibiting oxidative stress, inflammation by inhibiting the HMGB1/TLR4/NF-κB, and NLRP3/inflammasome pathway.

Huaiyu pill alleviates inflammatory bowel disease in mice blocking toll like receptor 4/ myeloid differentiation primary response gene 88/ nuclear factor kappa B subunit 1 pathway.

OBJECTIVE: To investigate the therapeutic effects of Huaiyu pill (, HYP) on inflammatory bowel disease (IBD) and the underlying mechanisms have not been elucidated. METHODS: To establish the IBD model, mice were administered with dextran sulfate sodium (DSS). Mice were intragastrically pre-treated with sulfasalazine (SASP) and HYP. Disease activity index (DAI) and colon length were monitored, and the colonic tissues were subjected to hematoxylin-eosin staining. Pro-inflammatory factors and vascular inflammation-related proteins were determined using enzyme-linked immunosorbent assay (ELISA). The potential mechanisms of HYP were examined using network pharmacology analysis.The expressions of zona occludens 1 (ZO-1), occludin, toll like receptor 4 (TLR4), myeloid differentiation primary response gene 88 (MYD88), and nuclear factor kappa B p65 subunit (NF-κB p65) in colon tissues were examined using Western blotting or immunohistochemical analyses. RESULTS: Pre-treatment with HYP enhanced the colon length, decreased DAI scores, and mitigated histopathological alterations in DSS-treated mice. HYP alleviated intestinal inflammation by downregulating the levels of interleukin 1 beta (IL-1ß), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α) and interleukin 17 (IL-17). Additionally, HYP suppressed the disruption of the gut barrier by upregulating the ZO-1, occludin, and mucin 2 (MUC2) levels and downregulating the endothelin 1 (ET-1) and erythropoietin (EPO) levels. Network pharmacological analysis and experimental results revealed that HYP downregulated the colonic tissue levels of TLR4, MYD88, and NF-κB p65 in DSS-treated mice. CONCLUSION: This study investigated the in vivotherapeutic effects of HYP on IBD and the underlying molecular mechanisms. These findings provide an experimental foundation for the clinical application of HYP.

Subgroup Analysis of TLR2, -3, -4 and -8 in Relation to the Severity of Clinical Manifestations of Cervical HPV Infection.

We present the findings of assessing the expression levels of extracellular TLR2 and TLR4 and intracellular TLR3 and TLR8 correlating with the severity of clinical manifestations of HPV infection. A total of 199 women took part in a single-center prospective comparative research study on TLR2, TLR3, TLR4 and TLR8 expression in HPV-related cervical lesions. TLRs' mRNA expression was analyzed using real-time reverse transcription polymerase chain reaction (RT-PCR). Our results indicate the potential significance of TLR3, TLR4 and TLR8 in responding to HPV infection and its progression to SILs and CC, highlighting the importance of HPV polyinfection in relation to TLR4 and TLR8.

Synergistic immune augmentation enabled by covalently conjugating TLR4 and NOD2 agonists.

Enhancing the efficacy of subunit vaccines relies significantly on the utilization of potent adjuvants, particularly those capable of triggering multiple immune pathways. To achieve synergistic immune augmentation by Toll-like receptor 4 agonist (TLR4a) and nucleotide-binding oligomerization-domain-containing protein 2 agonist (NOD2a), in this work, we conjugated RC529 (TLR4a) and MDP (NOD2a) to give RC529-MDP, and evaluated its adjuvanticity for OVA antigen. Compared to the unconjugated RC529+MDP, RC529-MDP remarkably enhanced innate immune responses with 6.8-fold increase in IL-6 cytokine, and promoted the maturation of antigen-presenting cells (APCs), possibly because of the conjugation of multiple agonists ensuring their delivery to the same cell and activation of various signaling pathways within that cell. Furthermore, RC529-MDP improved OVA-specific antibody response, T cells response and the memory T cells ratio relative to the unconjugated mixture. Therefore, covalently conjugating TLR4 agonist and NOD2 agonist was an effective strategy to enhance immune responses, providing the potential to design and develop more effective vaccines.

Sodium houttuyfonate induces bacterial lipopolysaccharide shedding to promote macrophage M1 polarization against acute bacterial lung infection.

Sodium houttuyfonate (SH), derived from the widely utilized natural herb Houttuynia cordata, exhibits an effective therapeutic effect on various diseases, including bacterial and fungal infections, especially the respiratory tract infection. Therefore, the anti-microbial mechanisms of SH may be different from the single-target action mechanism of conventional antibiotics, and further research is needed to clarify this. Firstly, we discovered that SH can effectively intervene in mouse lung infections by reducing bacterial load and acute inflammation response related to pneumonia caused by Pseudomonas aeruginosa. Interestingly, our results confirmed that SH has surface activity and can directly induce changes in the cell wall the shedding of surface lipopolysaccharide (LPS). Additionally, we found that SH-induced shedding of LPS can induce M1 polarization of macrophages in the early stage, leading to the production of corresponding polarization effector molecules. Subsequently, we discovered that SH-induced M1 polarization cells can effectively phagocytose and kill bacterial cells. The protein expression results indicated that SH can enhance the expression of M1 polarization pathway of TLR4/MyD88/NF-κB during the initial phase of macrophage and pathogen interaction. In summary, our results imply that SH could directly induce the shedding of P. aeruginosa LPS in a surfactant-like manner. Afterwards, the SH induced abscisic LPS can initiate the TLR4/MyD88/NF-κB immune pathway to trigger the M1 polarization of macrophages, which might intervene the P. aeruginosa-caused acute lung infection at early stage. Based on these findings, we attempted to coin the term "immune feedback eradication mechanism against pathogen of natural product" to describe this potent antimicrobial mechanism of SH.

Sheep (Ovis aries) Milk Exosomal miRNAs Attenuate Dextran Sulfate Sodium-Induced Colitis in Mice via TLR4 and TRAF-1 Inhibition.

Mammalian milk exosomal miRNAs play an important role in maintaining intestinal immune homeostasis and protecting epithelial barrier function, but the specific miRNAs and whether miRNA-mediated mechanisms are responsible for these benefits remain a matter of investigation. This study isolated sheep milk-derived exosomes (sheep MDEs), identifying the enriched miRNAs in sheep MDEs, oar-miR-148a, and oar-let-7b as key components targeting TLR4 and TRAF1, which was validated by a dual-luciferase reporter assay. In dextran sulfate sodium-induced colitis mice, administration of sheep MDEs alleviated colitis symptoms, reduced colonic inflammation, and systemic oxidative stress, as well as significantly increased colonic oar-miR-148a and oar-let-7b while reducing toll-like receptor 4 (TLR4) and TNF-receptor-associated factor 1 (TRAF1) level. Further characterization in TNF-α-challenged Caco-2 cells showed that overexpression of these miRNAs suppressed the TLR4/TRAF1-IκBα-p65 pathway and reduced IL-6 and IL-12 production. These findings indicate that sheep MDEs exert gastrointestinal anti-inflammatory effects through the miRNA-mediated modulation of TLR4 and TRAF1, highlighting their potential in managing colitis.

Chlorogenic Acid Enhances the Intestinal Health of Weaned Piglets by Inhibiting the TLR4/NF-κB Pathway and Activating the Nrf2 Pathway.

Chlorogenic acid (CGA) is a natural polyphenol with potent antioxidant and anti-inflammatory activities. However, the exact role of it in regulating intestinal health under oxidative stress is not fully understood. This study aims to investigate the effects of dietary CGA supplementation on the intestinal health of weaned piglets under oxidative stress, and to explore its regulatory mechanism. Twenty-four piglets were randomly divided into two groups and fed either a basal diet (CON) or a basal diet supplemented with 200 mg/kg CGA (CGA). CGA reduced the diarrhea rate, increased the villus height in the jejunum, and decreased the crypt depth in the duodenum, jejunum, and ileum of the weaned piglets (p < 0.05). Moreover, CGA increased the protein abundance of Claudin-1, Occludin, and zonula occludens (ZO)-1 in the jejunum and ileum (p < 0.05). In addition, CGA increased the mRNA expression of pBD2 in the jejunum, and pBD1 and pBD2 in the ileum (p < 0.05). The results of 16S rRNA sequencing showed that CGA altered the ileal microbiota composition and increased the relative abundance of Lactobacillus reuteri and Lactobacillus pontis (p < 0.05). Consistently, the findings suggested that the enhancement of the intestinal barrier in piglets was associated with increased concentrations of T-AOC, IL-22, and sIgA in the serum and T-AOC, T-SOD, and sIgA in the jejunum, as well as T-AOC and CAT in the ileum caused by CGA (p < 0.05). Meanwhile, CGA decreased the concentrations of MDA, IL-1ß, IL-6, and TNF-α in the serum and jejunum and IL-1ß and IL-6 in the ileum (p < 0.05). Importantly, this study found that CGA alleviated intestinal inflammation and oxidative stress in the piglets by inhibiting the TLR4/NF-κB signaling pathway and activating the Nrf2 signaling pathway. These findings showed that CGA enhances the intestinal health of weaned piglets by inhibiting the TLR4/NF-κB pathway and activating the Nrf2 pathway.

Aphthous stomatitis - computational biology suggests external biotic stimulus and immunogenic cell death involved.

BACKGROUND: The exact cause of recurrent aphthous stomatitis is still unknown, making it a challenge to develop effective treatments. This study employs computational biology to investigate the molecular basis of recurrent aphthous stomatitis, aiming to identify the nature of the stimuli triggering these ulcers and the type of cell death involved. METHODS: To understand the molecular underpinnings of recurrent aphthous stomatitis, we used the Génie tool for gene identification, targeting those associated with cell death in recurrent aphthous stomatitis. The ToppGene Suite was employed for functional enrichment analysis. We also used Reactome and InteractiVenn for protein integration and prioritization against a PANoptosis gene list, enabling the construction of a protein-protein interaction network to pinpoint key proteins in recurrent aphthous stomatitis pathogenesis. RESULTS: The study's computational approach identified 1,375 protein-coding genes linked to recurrent aphthous stomatitis. Critical among these were proteins responsive to bacterial stimuli, especially high mobility group protein B1 (HMGB1), toll-like receptor 2 (TLR2), and toll-like receptor 4 (TLR4). The enrichment analysis suggested an external biotic factor, likely bacterial, as a triggering agent in recurrent aphthous stomatitis. The protein interaction network highlighted the roles of tumor necrosis factor (TNF), NF-kappa-B essential modulator (IKBKG), and tumor necrosis factor receptor superfamily member 1A (TNFRSF1A), indicating an immunogenic cell death mechanism, potentially PANoptosis, in recurrent aphthous stomatitis. CONCLUSION: The findings propose that bacterial stimuli could trigger recurrent aphthous stomatitis through a PANoptosis-related cell death pathway. This new understanding of recurrent aphthous stomatitis pathogenesis underscores the significance of oral microbiota in the condition. Future experimental validation and therapeutic strategy development based on these findings are necessary.