Toll-like Receptor 4 Protein Research Articles

Anti-tumor and Phenotypic Regulation Effect of Matrine on Dendritic Cells through Regulating TLRs Pathway.

To investigate the effects of matrine on antigen presentation of dendritic cells (DCs), and to explore the pharmacological mechanism of matrine on anti-tumor effect. Different concentrations (0, 1, 2, 4, 8 and 16 µ g/mL) of matrine were co-cultured with DCs, the harvested DCs were co-cultured with antigens of Lewis lung cancer (LLC) cells, and then DCs and T cells were co-cultured to produce DCs-activated killer (DAK) cells, which have significant tumor-killing activity. The expression of cytokines, mRNA and protein of toll-like receptors (TLRs) in DCs were detected by enzyme linked immunosobent assay, polymerase chain reaction and Western blot, respectively. And the killing effect of DAK were measured by MTT assay. Matrine significantly increased the mRNA expression of TLR7, TLR8, myeloid differentiation factor 88 (MyD88), tumor necrosis factor receptor-associated factor 6 (TRAF-6) and I κ B kinase (IKK), as well as the protein expression of TLR7 and TLR8, and up-regulated the levels of interleukin-12 (IL-12), IL-6 and tumor necrosis factor-α (TNF-α), meanwhile, it also increased the expressions of MHC-II, CD54, CD80 and CD86 in DCs. DCs-activated effector T cells had significant tumor-killing activity. When the concentration of matrine was more than 4 µg/mL, all indices had significant difference (P<0.01 or P<0.05). Matrine plays an anti-tumor role by regulating TLRs signal transduction pathway, promoting the secretion of inflammatory cytokines and enhancing immune function.

Inhibition of proliferation and migration and induction of apoptosis in glioma cells by silencing TLR4 expression levels via RNA interference.

The objective of the present study was to investigate the expression levels of toll-like receptor 4 (TLR4) in glioma cells and the mechanisms underlying its regulatory effects on proliferation, migration and apoptosis of glioma cells. A total of three TLR4 silencing short hairpin (sh)RNA plasmids were established, and Lipofectamine® was used to the transfect the human glioma cell line U-87MG. Transfection efficiency was measured via flow cytometry. The interference plasmid exhibiting the largest silencing effect on TLR4 was screened for subsequent experiments using puromycin. Reverse transcription-quantitative PCR and western blot analysis were used to detect the TLR4 gene and protein expression levels, respectively, in stably transfected cells. Flow cytometry measured cell cycle and apoptosis and a wound healing assay was employed to assess the migration ability of transfected cells. The proliferation of transfected cells was detected using Cell Counting Kit-8 assay. TLR4-sh2 exhibited the highest transfection efficiency. Following transfection of U-87MG cells with TLR4-sh2 and negative control (NC) plasmids for 48 h and screening by puromycin, stable transfected cells were named U-87MG-Sh and U-87MG-NC cells respectively. The TLR4 gene and protein expression levels in the U-87MG-Sh cells were significantly lower than in U-87MG and U-87MG-NC cells. The apoptosis rate and the percentage of G0/1 cells were significantly higher, whereas the cell proliferation rate was notably lower, in U-87MG-Sh cells than in the U-87MG-NC and U-87MG cells. The proliferation rate and the cell migration ability of U-87MG-Sh cells were significantly lower than those of U-87MG-NC and U-87MG cells. TLR4 is associated with the proliferation of glioma cells. Inhibition of TLR4 expression levels significantly inhibited proliferation of glioma cells and induced apoptosis. The present study provided insights into the mechanisms associated with the development, progression and invasion ability of glioma cells.

Genome-wide analysis of Toll-like receptors in zebrafish and the effect of rearing temperature on the receptors in response to stimulated pathogen infection.

Water temperature has a major influence on the host innate immune defence and the infectivity of pathogens in ectothermic teleosts. Toll-like receptors (TLRs) are the first and well-characterized innate immune receptors that are conserved in vertebrates. However, little is known about the effect of temperature variation on TLRs in fish species. In this study, we used adult zebrafish as a research model to investigate the effect of water temperature on TLRs. Whole genome searches identified 20 TLR homologue genes in zebrafish. Multiple sequence alignment and protein structure analysis revealed the conserved domains for these TLR proteins. To identify TLR genes related to temperature variation, TLR family genes from 12 species with different body temperatures were assigned to conduct phylogenetic analyses. Based on the phylogenetic relationships, TLR3, TLR4, TLR5 and TLR20~21 were selected as candidate genes. Immunostimulation data indicated that TLR3, TLR5, and TLR21 were more sensitive to temperature variation and their expression levels were affected in response to pathogen stimulation. Taken together, our results provide a new opportunity to understand the roles of temperature on host innate immune response in fishes and have broader implications for disease prevention in aquaculture.

Virtual screening of black rice anthocyanins as antiobesity through inhibiting TLR4 and JNK pathway

Obesity is one of metabolic syndrome and have several complications including type 2 diabetes mellitus and inflammations. To reduce the complications and prevent the obesity, some natural constituents has been tested. This study proved the screening of cyanidin, cyanidin-3-O-glucoside, peonidin and peonidin-3-O-glucoside for inhibiting TLR4 and JNK protein using in-silico study. Four black rice anthocyanins, cyanidin, cyanidin-3-O-glucoside, peonidin and peonidin-3-O-glucoside as ligands taken out from PubChem database. Toll-like receptor 4 (TLR4) and c-Jun NH2-terminal kinase as target protein retrieved from protein data bank. Both of anthocyanins and proteins were docked by Hex 8.0 software and examined using Discovery studio v.19. All black rice anthocyanins interacted with TLR4 and JNK proteins. Cyanidin-3-O-glucoside, cyanidin, peonidin-3-O-glucoside and peonidin inhibit TLR4 in substrate residues site, while those anthocyanins directly inhibited the JNK protein in ATP active sites, gatekeeper residues, and phosphorylation sites. Those data indicated that four kind of anthocyanins that detected on black rice have functional role as anti-obesity. Further in-vivo or in-vitro research are required to support this experiment.

Endotoxin Tolerance in Abdominal Aortic Aneurysm Macrophages, In Vitro: A Case-Control Study.

Macrophages are implicated in the pathogenesis of abdominal aortic aneurysm (AAA). This study examined the environmentally conditioned responses of AAA macrophages to inflammatory stimuli. Plasma- and blood-derived monocytes were separated from the whole blood of patients with AAA (30–45 mm diameter; n = 33) and sex-matched control participants (n = 44). Increased concentrations of pro-inflammatory and pro-oxidant biomarkers were detected in the plasma of AAA patients, consistent with systemic inflammation and oxidative stress. However, in monocyte-derived macrophages, a suppressed cytokine response was observed in AAA compared to the control following stimulation with lipopolysaccharide (LPS) (tumor necrosis factor alpha (TNF-α) 26.9 ± 3.3 vs. 15.5 ± 3.2 ng/mL, p < 0.05; IL-6 3.2 ± 0.6 vs. 1.4 ± 0.3 ng/mL, p < 0.01). LPS-stimulated production of 8-isoprostane, a biomarker of oxidative stress, was also markedly lower in AAA compared to control participants. These findings are consistent with developed tolerance in human AAA macrophages. As Toll-like receptor 4 (TLR4) has been implicated in tolerance, macrophages were examined for changes in TLR4 expression and distribution. Although TLR4 mRNA and protein expression were unaltered in AAA, cytosolic internalization of receptors and lipid rafts was found. These findings suggest the inflamed, pro-oxidant AAA microenvironment favors macrophages with an endotoxin-tolerant-like phenotype characterized by a diminished capacity to produce pro-inflammatory mediators that enhance the immune response.

Antinociception induced by artemisinin nanocapsule in a model of postoperative pain via spinal TLR4 inhibition.

Artemisinin (ART) was initially described for the control of inflammation and pain. However, the mechanisms involved with its antinociceptive effect are still poorly understood. Thus, this present study aimed to investigate the effect of ART in both free and nanocapsulated form on postoperative pain, as well as the participation of the spinal Toll-like receptor 4 (TLR4) in this process. Postoperative pain was induced using the skin/muscle incision retraction (SMIR) model in male Swiss mice. After 3 and 28days of SMIR, the animals received an intrathecal injection of free or nanocapsulated ART, and the nociceptive threshold was evaluated by von Frey filament test. To evaluate the involvement of the microglia, astrocytes, and TLR4, minocycline (a microglia inhibitor), fluorocitrate (an astrocyte inhibitor), and Lipopolysaccharide Rhodobacter sphaeroides (LPS-RS), a TLR4 antagonist, were intrathecally injected on the third day of SMIR. The levels of spinal TLR4 protein and proinflammatory cytokines tumor necrosis factor-alpha (TNF-α), and interleukin-1-beta (IL-1β) were quantified by western blot and enzyme-linked immunosorbent assay, respectively. The results showed that free ART reduced postoperative pain (P < 0.001, F5,30 = 7.49, 16.66% for 1000ng dose; and P < 0.01, F5,30 = 7.49, 14.58% for 500ng dose) on the 3rd day of SMIR; while the ART nanocapsule had this effect on both the third (P < 0.001; F5,30 = 4.94; 43.75, 39.58 and 72.91% for the 250, 500 and 1000ng doses, respectively) and 28th (P < 0.05; F5,30 = 7.71; 29.16 and 33.33% for the 500 and 1000ng doses, respectively) day. The ART nanocapsule had a more potent and longer antinociceptive effect than free ART or morphine. Postoperative pain was also reduced by minocycline and LPS-RS. The ART nanocapsule also reduced the increased levels of TLR4, TNF-α, and IL-1β induced by SMIR. These data suggest that the ART nanocapsule has a potent analgesic effect on postoperative pain at the spinal level, and this response involves the inhibition of TLR4 and the proinflammatory cytokines TNF-α and IL-1β.

Cottonseed oil alleviates ischemic stroke injury by inhibiting the inflammatory activation of microglia and astrocyte

BackgroundIschemic stroke is the second leading cause of death globally. The narrow time window for administering effective thrombolytic therapy motivates the search for alternative prevention strategies. Microglia and astrocyte activation-mediated inflammation play a pivotal role in ischemic stroke injury. Cottonseed oil (CSO) has been shown to exert anti-inflammatory effects against peripheral tissue injury, although CSO is mostly used as a solvent for lipid-soluble drugs. However, the role of CSO in neuroprotection against stroke has not been previously reported.MethodsWe treated adult male rats with CSO (1.3 ml/kg, subcutaneous injection, once every other day for 3 weeks) and then constructed a middle cerebral artery occlusion (MCAO) model followed by 24 h of reperfusion. Then, we measured the neurological scores, infarction volume, neuronal injury, and brain edema; we also measured the levels of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α), degree of microglial and astrocytic activation, protein expression levels of Toll-like receptor 4 (TLR4), nuclear factor kappa B (NF-κB), C3d and S100A10, and the presence of A1 type astrocytes and A2 type astrocytes.ResultsWe found that CSO treatment significantly improved the neurological deficit, reduced infarction volume, and alleviated neuronal injuries, blood–brain barrier (BBB) disruption, and brain edema. Additionally, CSO treatment significantly reduced microglial and astrocytic activation, inhibited TLR4 and NF-κB protein expression, and reduced the release of IL-1β, IL-6, and TNF-α. Finally, CSO treatment significantly decreased the number of C3d/glial fibrillary acidic protein (GFAP)-positive cells and C3d protein expression, and increased the number of S100A10/GFAP-positive cells and S100A10 protein expression.ConclusionOur results first found that CSO treatment alleviated ischemic stroke injury by reducing microglial and astrocytic activation and inflammation, which was related to the inhibition of TLR4/NF-κB pathway and the reduction of A1 phenotype neurotoxic astrocyte activation, suggesting that CSO could be a new strategy in the prevention of ischemic stroke.

Ethanolic Garcinia mangostana extract and α-mangostin improve dextran sulfate sodium-induced ulcerative colitis via the suppression of inflammatory and oxidative responses in ICR mice

Ethnopharmacological relevanceUlcerative colitis (UC) is an inflammatory disorder of the colon. Garcinia mangostana Linn. (GM) has been traditionally used for its anti-inflammatory and antioxidant activities. Aim of the study:The effects of GM and its bioactive constituent α-mangostin on dextran sulfate sodium (DSS)-induced UC in mice were investigated. Materials and methodsAdult ICR mice (n = 63) were pretreated with ethanolic GM extract at 40, 200, and 1000 mg/kg/day (GM40, GM200, and GM1000), α-mangostin at 30 mg/kg/day, or sulfasalazine at 100 mg/kg/day (SA) for 7 consecutive days. On days 4–7, UC was induced in the mice by the oral administration of DSS (40 kDa, 6 g/kg/day), while control mice received distilled water. The UC disease activity index (DAI) and histological changes were recorded. The activities of myeloperoxidase, catalase, and superoxide dismutase, and the levels of reactive oxygen species (ROS), nitric oxide (NO), and malondialdehyde (MDA) were determined. The mRNA expression of inflammatory related genes including proinflammatory cytokine Tnf-α, Toll-like receptor (Tlr-2), adhesion molecules (Icam-1 and Vcam-1), and monocyte chemoattractant protein (Mcp-1) were evaluated. ResultsTreatment with GM or α-mangostin decreased the UC DAI and protected against colon shortening and spleen and kidney enlargement. GM and α-mangostin prevented histological damage, reduced mast cell infiltration in the colon, and decreased myeloperoxidase activity. GM and α-mangostin increased catalase and superoxide dismutase activity and decreased ROS, NO, and MDA production. GM downregulated mRNA expression of Tnf-α, Tlr-2, Icam-1, Vcam-1, and Mcp-1. ConclusionsGM and α-mangostin attenuated the severity of DSS-induced UC via anti-inflammatory and antioxidant effects. Therefore, GM is a promising candidate for development into a novel therapeutic agent for UC.

Effect of moxibustion on TLR4/MyD88/NF-κB signaling pathway in colon of diarrhea-predo-minant irritable bowel syndrome rats

To observe the effect of moxibustion on serum inflammatory factors, Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88) and nuclear factor Kappa B (NF-κB) in colon tissue of rats with diarrhea-predominant irritable bowel syndrome (IBS-D)，so as to explore the mechanism of moxibustion in the treatment of IBS-D. Healthy male SD rats were randomly divided into blank group, model group and moxibustion group, with 8 rats in each group. The IBS-D model was established by chronic restraint combined with gavage of Senna-leaf solution. The rats of the moxibustion group was treated with moxibustion at "Tianshu"(ST25)and "Shangjuxu"(ST37)for 30 min， once a day for 7 d. After the intervention, the rate of loose stools and the minimum threshold volume of abdominal withdrawal reflex (AWR) induced by colorectal distension were observed. The contents of serum inflammatory factors IL-1β, TNF-α and IL-6 were detected by ELISA. The pathological changes of rat colon were observed by H.E. staining. The average optical density of TLR4 and NF-κB (p65) in colon tissue was detected by immunohistochemistry. The relative expressions of TLR4, MyD88 and NF-κB (p65) mRNAs in colon tissues were detected by real-time fluorescence quantitative PCR, and the expression levels of TLR4, MyD88 and NF-κB (p65) proteins in colon tissues were detected by Western blot. There was a mild degree of inflammation in colon in rats of the model group. Compared with the blank group, the minimum volume threshold of AWR decreased significantly (P< 0.01), and the rate of loose stools, the contents of IL-1β, IL-6 and TNF-α in serum as well as the expressions of TLR4, MyD88, NF-κB (p65) mRNAs and protein in colon tissues were significantly increased in the model group (P<0.01). Compared with the model group, the inflammation was alleviated in colonic mucosa, the minimum volume threshold of AWR increased significantly (P<0.01), and rate of loose stools decreased significantly (P<0.01) in the moxibustion group, the contents of IL-1β, TNF-α and IL-6 in serum and the expression levels of TLR4, MyD88, NF-κB (p65) mRNAs and proteins in colon tissue decreased significantly in the moxibustion group (P<0.01). Moxibustion ST25 and ST37 can improve diarrhea symptom and visceral hypersensitivity in IBS-D rats, which may be related with its effects in inhibiting TLR4/MyD88/NF-κB signaling pathway and reducing the expression of inflammatory factors.

Environmental enrichment rescues cognitive impairment with suppression of TLR4-p38MAPK signaling pathway in vascular dementia rats

Increasing evidence demonstrated the promising effects of environmental enrichment (EE) on brain recovery and cognitive performance in animal models of various diseases. However, the effect and molecular mechanisms of EE on vascular dementia (VD) remain to be studied. The aim of this study was to explore the effect of EE on cognitive decline and its mechanism. Sprague-Dawley rats underwent 2-vessel occlusion (2-VO) surgery or sham operation. Subsequently, rats were kept in EE for 4 weeks. In Morris water maze (MWM) test, we demonstrated that EE significantly improved cognitive function in rats with VD. HE staining exhibited morphological changes of neurons and quantitative analysis of TUNEL showed increased apoptotic neurons in hippocampal CA1 region following 2-VO. Results from RT-qPCR showed up-regulation of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) after 2-VO. Western blotting analysis revealed enhanced toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MYD88) and phosphorylated p38 mitogen-activated protein kinase (p-p38MAPK) in 2-VO rats. Whereas administration of EE reduced apoptotic neurons, down-regulated inflammatory factors. Moreover, EE suppressed protein expression of TLR4-p38MAPK pathway. Spearman correlation analysis showed that improved cognitive function was associated with decreased expression of TLR4 and p-p38MAPK proteins. Thus, our study proved that EE has a prominent effect on cognitive impairment and neuronal damage following 2-VO by attenuating inflammation and apoptosis, which may be realized via inhibiting the TLR4-P38MAPK signaling pathway.

Impact of an anti-Salmonella. Typhimurium Bacteriophage on intestinal microbiota and immunity status of laying hens.

Typhoid is a distinct gastrointestinal disease that largely affects the public by consumption of inadequately or partially cooked eggs from contaminated laying hen farms. This has led the research on laying hens to focus on controlling the contamination by an effective anti-Salmonella spp. agent in the intestine. The treatments included, control, without challenge; PC, Salmonella typhimurium challenged (STC); BP5, 5ppm bacteriophage/kg+STC; BP10, 10ppm bacteriophage/kg+STC, on Salmonella shedding, body organs inflammatory reactions, and expression of toll-like receptor (TLR), pro-inflammatory cytokines, and heat shock protein (HSP) in the jejunum, liver,and thigh muscle in the STC laying hens. The RT-PCR method was used to enumerate the number of Salmonella typhimurium in the organs. The birds in the STC groups exhibited the increased population of Salmonella spp. in the excreta (p<.01). In the STC groups, the BP5 and BP10 laying hens exhibited a lower (p<.01) population of Salmonella spp. in the excreta at d 7 after STC. Supplementation of bacteriophage significantly decreased (p<.01) the colonization of S. Typhimurium in the spleen, oviduct, caecum and excreta. Among the STC treatments, the BP10 laying hens showed lower (p<.01) mRNA expression of interferon-γ (IFNγ) and TLR-4 in the jejunum compared with the PC treatment. After the STC, dietary supplementation with BP5 or BP10 decreased (p<.01) the mRNA expressions of IFNγ, HSP-27 and tumour necrosis factor-α in the liver compared with the PC treatment. These results suggest that bacteriophage can be used as an effective agent to decrease S. Typhimurium contamination in laying hens and possibly lower S. Typhimurium transfer to foods.

Hydroxysafflor yellow A improves diabetes-induced renal fibrosis

IntroductionThis study aimed to discuss the use of hydroxysafflor yellow A (HSYA) to improve renal fibrosis induced by diabetes and its relative mechanisms, as well as to evaluate the level of renal histopathology and fibrosis in different rat groups.Material and methodsSprague-Dawley (SD) rats (n = 27) were divided into the normal control (NC), diabetes mellitus (DM), and HSYA groups. The miRNA-140-5p mRNA, blood glucose (BG), 24-h urine protein (UP), total cholesterol (TC), triglyceride (TG), total anti-oxidant capacity (T-AOC), malondialdehyde (MDA), interleukin-6 (IL-6), and tumour necrosis factor-α (TNF-α) were measured in different groups. Moreover, the relative protein expression was measured via immunohistochemistry (IHC) assay. In the in vitro cell experiment, we discussed the effects of miRNA-140-5p on renal fibrosis induced by diabetes. Toll-like receptor 4 (TLR4), nuclear factor B (p65) (NF-κB(p65)), NOD-like receptor protein 3 (NLRP3), Notch2, and collagen IV (Col-IV) protein expression were evaluated using western blotting in the different cell groups. We evaluated the important protein expressions and NF-κB(p65) nuclear volume by cellular immunofluorescence. A correlation between miRNA-140-5p and TLR4 was found by dual-luciferase reporter assay.ResultsIn the in vivo study, HSYA improved diabetes-induced renal fibrosis. The severity of fibrosis significantly decreased after treatment with HSYA. In the HSYA group, the miRNA-140-5p mRNA, BG, 24-h UP, TC, TG, T-AOC, MDA, IL-6, and TNF-α significantly improved, as well as the TLR4, NF-κB(p65), NLRP3, Notch2, and Col-IV proteins. In the in vitro experiment, miRNA-140-5p was significantly decreased after treatment with HSYA in diabetes-induced renal fibrosis.ConclusionsHSYA improved diabetes-induced renal fibrosis by regulating miRNA-140-5p.

Levonorgestrel Ameliorates Adenomyosis via lncRNA H19/miR-17/TLR4 Pathway.

PurposeTo explore the mechanism of levonorgestrel (LNG)-ameliorating adenomyosis through long non-coding RNA H19 (lncRNA H19)/miR-17/Toll-like receptor 4 (TLR4) pathway.Patients and MethodsA total of 71 cases of adenomyosis and 54 cases of normal endometrium were sampled. Quantitative polymerase chain reaction (qPCR) was employed to quantify lncRNA H19, miR-17, and TLR4 mRNA, while Western blot (WB) was used to quantify TLR4 protein. Effects of LNG on normal endometrial stromal cells (ESCs) were evaluated. Suppression/over-expression vectors of lncRNA H19, miR-17, and TLR4 were constructed to observe their effects on ESCs.ResultsMiR-17 and TLR4 mRNA were up-regulated and lncRNA H19 was down-regulated in adenomyosis. After LNG treatment, lncRNA H19 was up-regulated while miR-17 and TLR4 were down-regulated. LNG, up-regulation of lncRNA H19, and down-regulation of miR-17 and TLR4 portend increased apoptosis, G1-arrested cells, as well as inhibited inflammation. Dual-luciferase reporter (DLR) assay conformed the targeting relation of lncRNA H19/miR-17/TLR4 pathway.ConclusionLNG ameliorates adenomyosis via lncRNA H19/miR-17/TLR4 pathway.

Integrated System Pharmacology and In Silico Analysis Elucidating Neuropharmacological Actions of Withania somnifera in the Treatment of Alzheimer's Disease.

Withania somnifera (WS), also referred to as Medhya Rasayana (nootropic or rejuvenating), has traditionally been prescribed for various neurological ailments, including dementia. Despite substantial evidence, pharmacological roles of WS, neither as nootropic nor as an antidementia agent, are well-understood at the cellular and molecular levels. We aimed at elucidating the pharmacological action mechanisms of WS root constituents against Alzheimer's Disease (AD) pathology. Various bioinformatics tools and resources, including DAVID, Cytoscape, NetworkAnalyst and KEGG pathway database were employed to analyze the interaction of WS root bioactive molecules with the protein targets of AD-associated cellular processes. We also used a molecular simulation approach to validate the interaction of compounds with selected protein targets. Network analysis revealed that β-sitosterol, withaferin A, stigmasterol, withanolide A, and withanolide D are the major constituents of WS root that primarily target the cellular pathways such as PI3K/Akt signaling, neurotrophin signaling and toll-like receptor signaling and proteins such as Tropomyosin receptor Kinase B (TrkB), Glycogen Synthase Kinase-3β (GSK-3β), Toll-Like Receptor 2/4 (TLR2/4), and β-secretase (BACE-1). Also, the in silico analysis further validated the interaction patterns and binding affinity of the major WS compounds, particularly stigmasterol, withanolide A, withanolide D and β-sitosterol with TrkB, GSK-3β, TLR2/4, and BACE-1. The present findings demonstrate that stigmasterol, withanolide A, withanolide D and β-sitosterol are the major metabolites that are responsible for the neuropharmacological action of WS root against AD-associated pathobiology, and TrkB, GSK-3β, TLR2/4, and BACE-1 could be the potential druggable targets.

Ketamine alleviates HMGB1-induced acute lung injury through TLR4 signaling pathway.

Acute lung injury (ALI) is a common critical respiratory disease that seriously threatens human health. Ketamine has good anti-inflammatory and immune-regulating properties that can delay the lung injury process. High mobility group box protein 1 (HMGB1) plays an important role in the occurrence, development and treatment of ALI. Toll-like receptor 4 (TLR4) is the receptor for HMGB1. The aim of this study was to determine the role of the HMGB1 TLR4 signaling pathway in the treatment of ALI using ketamine. A total of 30 healthy, male, 8-week-old Sprague-Dawley rats were randomly, equally divided into a control group, an lipopolysaccharide (LPS) group and a ketamine group. In order to establish a rat ALI model, 15 mg/kg of LPS was injected into the femoral veins. Ketamine was intravenously injected (10 mg/kg) into the experimental group rats. The rats were euthanized 24 h after modeling and lung tissue samples were collected. Western blot was used to test TLR4, MyD88, TRAF-6, LOX-1, and HMGB1 protein expression in the lung tissue. Real-time polymerase chain reaction (RT-PCR) was performed to detect TLR4, MyD88, TRAF-6, LOX-1, and HMGB1 mRNA levels. Compared with the controls, the LPS group had significantly higher TLR4, MyD88, TRAF-6, LOX-1, and HMGB1 mRNA and protein levels (p < 0.05). These levels were significantly lower after ketamine intervention in comparison with the LPS group (p < 0.05). A positive correlation was found between TLR4 and HMGB1 expression in the LPS and ketamine groups (r = 0.952, p < 0.001; r = 0.941, p < 0.001). Ketamine attenuates HMGB1-induced ALI, possibly by regulating the TLR4 signaling pathway.

Siwu Paste protects bone marrow hematopoietic function in rats with blood deficiency syndrome by regulating TLR4/NF-κB/NLRP3 signaling pathway

Ethnopharmacological relevanceSiwu Paste (SWP) was recorded in the first national Pharmacopoeia of China, “Tai Ping Hui Min He Ji Ju Fang”, it showed excellent effects in regulating all syndromes relevant to blood.Aim of the study: This study aimed to investigate the protective effects of Siwu Paste (SWP) on bone marrow hematopoietic by using rats’ model with blood deficiency syndrome induced by chemotherapy. Materials and methodsAnimal model with blood deficiency syndrome was successfully established by evaluating their peripheral blood cell level and erythrocyte membrane energy metabolism enzyme activity. Serum hematopoietic cytokine levels were detected by using Enzyme-linked immunosorbent assay (ELISA). Hematoxylin-Eosin (HE) staining method was used to observe the pathological morphology of femur bone marrow, and the viability of BMSC was detected by Cell Counting Kit (CCK-8). Furthermore, the expression of toll-like receptor 4 (TLR4), nuclear transcription factor kB (NF-κB), and NOD-like receptor protein 3 (NLRP3) protein in femur bone marrow were detected by using Western-blotting and High-content cell imaging analysis system (HCA). ResultsObtained results showed that SWP could significantly improve the status of anemia, regulate the expressions of serum hematopoietic cytokines, and protect bone marrow hematopoietic cells. Furthermore, the expressions of TLR4, NF-κB, and NLRP3 protein were inhibited in bone marrow hematopoietic cells. ConclusionsSiwu Paste (SWP) could recover the bone marrow hematopoietic functions in rats with blood deficiency syndrome. The therapeutic mechanism may be related to the regulation of serum hematopoietic cytokines, and inhibition of TLR4/NF-κB/NLRP3 signaling pathway.

Effect of electroacupuncture on intestinal Toll-like receptor 4 and nuclear factor-kappa B in obese rats

To investigate the effect of electroacupuncture (EA) on intestinal Toll-like receptor 4 (TLR4) and nuclear factor-kappa B (NF-κB) in obese rats, so as to explore the mechanism of action of acupuncture in losing weight. A total of 50 male Wistar rats were randomly divided into control and model groups. High-fat feed was used to establish a rat model of obesity, and after modeling, the 24 rats were randomly divided into model group, TLR4 inhibitor group, and EA group, with 8 rats in each group. The rats in the EA group were given EA at "Guanyuan" (CV4), "Zhongwan "(CV12), "Zusanli" (ST36), and" Fenglong" (ST40), 10 minutes each time, 3 times a week, and those in the TLR4 inhibitor group were given intraperitoneal injection of TAK-242 three times a week; the course of treatment was 8 weeks for both groups. Body weight and blood glucose were measured every two weeks. Co-immunoprecipitation was used to observe the interaction between TLR4 and NF-κB p65 in the intestinal tissue; electrophoretic mobility shift assay was used to measure the activity of NF-κB p65; Western blot was used to measure the protein expression of TLR4, phosphorylated nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha (p-IκBα), and NF-κB p65; quantitative real-time PCR was used to measure the mRNA expression of TLR4, NF-κB p65, and IκBα. Compared with the control group, the model group had significant increases in body weight, blood glucose, and protein and mRNA expression of TLR4 and NF-κB p65 (P<0.01, P<0.05), as well as significant enhancement in the interaction between TLR4 and NF-κB p65 and activity of NF-κB p65 (P<0.05，P<0.01). Compared with the model group, the EA group had a significant reduction in body weight (P<0.05), both of the EA group and the TLR4 inhibitor group had significant reductions in blood glucose, and protein and mRNA expression of TLR4, p-IκBα， and NF-κB p65 (P<0.05，P<0.01), as well as significant reductions in the activity of NF-κB p65 (P<0.01). EA can effectively regulate intestinal TLR4, inhibit the interaction between TLR4 and NF-κB p65, and reduce the activity of NF-κB p65, which may be a potential mechanism of EA in reducing body weight and blood glucose in obese rats.

TLR4 Receptor D299G/T399I Haplotype Polymorphism Is Associated with Insulin Resistance in Obese Female Subjects.

Background: Activation of Toll-like-receptor 4 (TLR4) causes chronic inflammation that can result in obesity and metabolic syndrome (MeS). Aim: This study aimed to investigate the role of TLR4 polymorphisms of TLR4D299G/T399I, and its impact on protein expression of TLR4 in obese female subjects. Methodology: A prospective cross-sectional association study was performed on Arab female subjects from Qatar University. The subjects were categorized according to BMI classifications into two groups: “obese; n = 69” and “non-obese; n = 136”. Anthropometric measurements, weight (kg), height (m) and waist circumference (WC) were evaluated, and the body mass index (BMI) was calculated. Fasting blood samples were collected, and assessment of glucose, lipid profile, C-reactive protein (CRP), leptin, IL-6 and insulin was performed. Insulin resistance was computed using HOMA-IR. Genotyping of the TLR4 polymorphisms of TLR4D299G (rs4986790) and TLR4T399I (rs4986791) was performed by the 5′ nuclease assay by TaqMan MGB probe. Flow cytometry was used to evaluate the monocyte cell surface expression of TLR4. Results: The frequency distribution of the genotype revealed that homozygous AA is the most frequent among obese subjects (86.4%) for (TLR4D299G, A > G) and the homozygous CC genotype is the most frequent (92.4%) for (TLR4T399I, C > T). Haplotype analysis of TLR4 D299G/T399I showed that GT carriers had a significant association with increased probability of insulin resistance (odds ratio = 4.73; 95% CI 1.19–18.90; p-value = 0.016). The monocyte cell surface of TLR4 was significantly higher by 1.3 folds in obese compared to non-obese subjects. Conclusions: TLR4 D299G/T399I haplotype polymorphism is associated with an increased risk of insulin resistance with the upregulation of TLR4 protein expression in obese subjects.

Selenomethionine Suppressed TLR4/NF-κB Pathway by Activating Selenoprotein S to Alleviate ESBL Escherichia coli-Induced Inflammation in Bovine Mammary Epithelial Cells and Macrophages.

Inflammation is the hallmark of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli-induced bovine mastitis. Organic selenium can activate pivotal proteins in immune responses and regulate the immune system. The present study aimed to investigate whether selenomethionine (SeMet) attenuates ESBL E. coli-induced inflammation in bovine mammary epithelial cells (bMECs) and macrophages. Cells were treated with 0, 5/10, 10/20, 20/40, or 40/60 μM SeMet for 12 h and/or inoculated with ESBL-E. coli [multiplicity of infection (MOI) = 5] for 4/6 h, respectively. We assessed inflammatory responses, including selenoprotein S (SeS), Toll-like receptor 4 (TLR4), Ikappa-B (IκB), phospho-NF-κB p65 (Ser536), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and lactate dehydrogenase (LDH) activities. Treatment with 40/60 μM SeMet promoted cell viability and inhibited LDH activities in both bMECs and macrophages. Inoculation with ESBL-E. coli reduced cell viability, which was attenuated by SeMet treatment in bMECs and macrophages. SeMet increased ESBL E. coli-induced downregulation of SeS and decreased LDH activities, TLR4, IκB, phospho-NF-κB p65 (Ser536), IL-1β, and TNF-α protein expressions in bMECs and macrophages. In addition, knockdown of SeS promoted protein expression of TLR4-mediated nuclear factor-kappa (NF-κB) pathway and BAY 11-708 inhibited TNF-α and IL-1β protein levels in bMECs and macrophages after ESBL-E. coli treatment. Moreover, ESBL-E. coli inoculation increased monocyte chemoattractant protein 1 (MCP-1), C–C motif ligand 3 (CCL-3), and CCL-5 mRNA expressions in bMECs. In conclusion, ESBL-E. coli induced expression of MCP-1, CCL-3, and CCL-5 in bMECs and then recruited and activated macrophages, whereas SeMet attenuated ESBL E. coli-induced inflammation through activated SeS-mediated TLR4/NF-κB signaling pathway in bMECs and macrophages.

MiR-145 Regulates the Chemoresistance of Hepatic Carcinoma Cells Against 5-Fluorouracil by Targeting Toll-Like Receptor 4.

Background5-fluorouracil (5-FU) is a common drug for hepatic carcinoma (HCC), but the drug resistance of clinical chemotherapy restricts its use. Studies have demonstrated that miRNA molecules can act as a chemoresistance regulator in drug resistance of tumors, whereas the role of miR-145 in the 5-FU-resistant HCC remains unclear.ObjectiveTo explore the prognostic value of miR-145 in HCC and its molecular mechanism in 5-FU-resistant HCC cells.MethodsA qRT-PCR assay was conducted to quantify miR-145 in HCC tissues and 5-FU-resistant HCC cells. The Cell Counting Kit-8 (CCK-8) and flow cytometry were adopted to analyze the proliferation and apoptosis of 5-FU-resistant HCC cells. The Western blot was adopted to quantify toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and apoptosis-related proteins. Moreover, an in vivo tumor xenotransplantation of nude mice was conducted to determine the effect of miR-145 on 5-FU-resistant HCC cells.ResultsMiR-145 was expressed lowly in HCC tissues and cells, and linked to high TNM staging and lymph node metastasis of HCC patients. Down-regulation of miR-145 indicated a poorer prognosis and it promoted drug resistance of HCC cells and inhibited cell apoptosis. In contrast, miR-145 overexpression improved the sensitivity of HCC cells to 5-FU and enhanced the inhibition of 5-FU on tumor growth. The luciferase reporter gene assay showed that TLR4 was the direct target of miR-145, and the Western blot assay revealed that overexpression of TLR4 reversed the inhibitory effect of miR-145 overexpression on TLR4 and MyD88 protein and the effects of it on apoptosis-related proteins.ConclusionMiR-145 is an inhibiting factor in HCC and can target TLR4 to mediate the chemoresistance of HCC, which may provide novel ideas for treating HCC.