Enhanced effect of κ-carrageenan on TNBS-induced inflammation in mice

BackgroundAs a sulfated polysaccharide, carrageenan has been widely used as common food additive.MethodsIn the present study, we investigated the effects of κ-carrageenan on TNBS-induced gut inflammation in mice. BALB/c mice were pretreated with κ-carrageenan for 14 days prior to the administration of TNBS.ResultsOur results showed that κ-carrageenan pretreatment aggravated the loss of body weight and further increased the mortality rate. Histological and morphological analyses revealed that the TNBS-induced colonic inflammation was deteriorated by the κ-carrageenan administration. The ratio of CD4⁺ CD25⁺ CD127dim/CD4⁺ of the κ-carrageenan + TNBS groups was significantly lower than that of the TNBS group. The expression of IL-2, TNF-α and IL-6 was significantly increased, whereas the expression of IL-10 was significantly decreased in the κ-carrageenan + TNBS groups. In addition, κ-carrageenan, together with TNBS, decreased the enzyme activity of SOD and GSH-px and up-regulated the expression of TLR4, NF-κB, p-ERK, p-JNK, p-Jun., IL-8 and MDA in the colonic mucosa.Conclusionsκ-Carrageenan aggravated the TNBS-induced intestinal inflammation, and such an effect could be associated with the oxidative stress and activation of TLR4-NF-κB and MAPK/ERK1/2 pathway.     

Neurogenic contraction of mouse rectum via the cyclooxygenase pathway: Changes of PGE2-induced contraction with dextran sulfate sodium-induced colitis

Recent reports suggest that cyclooxygenases (COXs) including COX-2 are constitutively expressed, and prostaglandins (PGs) regulate motility and/or contraction in the colon and rectum. This study examines the role of COXs in the regulation of neuromuscular function in longitudinal preparations of isolated rectum and distal colon (Side A, close to the transverse colon; and Side B, close to the rectum) in normal mice and after the induction of colitis by dextran sulfate sodium (DSS). In control rectum, electrical stimulation (ES)-induced contractions were inhibited by atropine and by COX inhibitors, in an independent manner. PGE₂ at 3 μM caused a marked contraction, but the secondary response at 20 min after the first application was 60% desensitized. In rectum from DSS-treated mice, spontaneous and ES-induced contractions were significantly less intense than in the control preparations, and the response to PGE₂ was abolished but that to 3 μM acetylcholine was not. In control distal colon, the responses to PGE₂ in neither side were desensitized by the repeated application. In DSS-treated distal colon, PGE₂ response was impaired in the two regions, and was desensitized on Side B more than Side A. DSS treatment impaired contractions by 40 mM KCl in rectum and on Side B but not Side A. DSS treatment increased COX-2 expression in rectum, but not in distal colon. These findings suggest that the induction of colitis by DSS affects ES- and PGE₂-regulated motility in the order rectum > distal colon close to the rectum > distal colon in mice.     

The O-methylation of chrysin markedly improves its intestinal anti-inflammatory properties: Structure–activity relationships of flavones

The aim of this study was to investigate whether methoxylated flavones versus their unmethylated analogs can modulate the intestinal inflammatory response.Flavone effects were assessed on soluble pro-inflammatory mediator (IL-8, IL-6, macrophage chemoattractant protein-1 (MCP-1), and cyclooxygenase-2 (COX-2)-derived PGE₂) production and on nuclear factor (NF)-κB activation in 3d-confluent and 21d-differentiated Caco-2 cells stimulated with interleukin (IL)-1β.Chrysin (CHRY) showed anti-inflammatory properties by decreasing COX-2-derived PGE₂ and reducing NF-κB activation. Compared to CHRY, the dimethoxylated form (CHRY-DM) significantly reduced the secretion of all pro-inflammatory mediators, except IL-8, at both cellular stages (P < 0.05); these effects being dose-dependent in 3d-cells. The reduction of NF-κB activation was significantly more pronounced with CHRY-DM. By evaluating other flavones, it was established that several structural dispositions of flavones seemed to be determinant in order to attenuate the intestinal inflammatory response, such as methoxylation of the 5- and 7-hydroxyl groups on the A-ring, non-methoxylation of the 3′-hydroxyl groups on the B-ring, and methoxylation of the 3-hydroxyl group on the C-ring. Of all flavones examined, CHRY-DM exhibited the strongest anti-inflammatory activity.These data indicate that, in the Caco-2 cell model, methoxylation of CHRY greatly improves its anti-inflammatory properties, probably through a more pronounced inhibition of the NF-κB signaling pathway. Nevertheless, methoxylation of other flavones was not systematically beneficial.     

Interleukin-37 suppresses ICAM-1 expression in parallel with NF-κB down-regulation following TLR2 activation of human coronary artery endothelial cells

IntroductionThe inflammatory receptor Toll-like receptors (TLRs) activation could induce endothelial inflammatory responses, which plays an important role in the development of many diseases including atherosclerosis. We already found that TLR2 activation of Peptidoglycan (PGN) stimulation could increase intercellular adhesion molecule-1 (ICAM-1) expression in HCAECs. Since anti-inflammatory cytokine interleukin (IL)-37 exhibits intra- and extracellular properties for suppressing innate inflammation, we want to investigate whether IL-37 suppresses ICAM-1 expression and this effect is in parallel with the inhibition of nuclear factor kappa B (NF-κB) activation upon PGN stimulation in HCAECs.MethodsHCAECs were treated with IL-37-transfection plasmid or silent mRNA or nothing for 24 h, and we test IL-37 expression by immunoblotting. Same treatments prior to PGN stimulation (10 μg/ml), we analyzed the expression of ICAM-1 and NF-κB mRNA at 0, 30 min, 1 and 2 h by real-time PCR. ICAM-1 protein at 24 h and NF-κB activation at 0–2 h were measured by immunoblotting.ResultsIL-37 and silent IL-37 transfection change the expression of IL-37 protein. Stimulation of PGN increased both NF-κB activation and ICAM-1 expression at mRNA and protein level, but these inflammatory cytokines’ expression was significantly decreased in IL-37-transfection cells. Interestingly, both NF-κB activation and ICAM-1 expression were significantly increased when IL-37 was silent.ConclusionsAs an anti-inflammatory cytokine, IL-37 could decrease both NF-κB and ICAM-1 expression upon TLR2 activation in HCAECs. The suppressed effect of IL-37 on ICAM-1 may be due to its inhibition on NF-κB.     

Epigallocatechin-3-gallate inhibits TLR4 signaling through the 67-kDa laminin receptor and effectively alleviates acute lung injury induced by H9N2 swine influenza virus

Epigallocatechin-3-gallate (EGCG) was found to inhibit the Toll-like receptor 4 (TLR4) pathway involved in influenza virus pathogenesis. Here, the effect of EGCG on TLR4 in an H9N2 virus-induced acute lung injury mouse model was investigated. BALB/c mice were inoculated intranasally with A/Swine/Hebei/108/2002 (H9N2) virus or noninfectious allantoic fluid, and treated with EGCG and E5564 or normal saline orally for 5 consecutive days. PMVECs were treated with EGCG or anti-67 kDa laminin receptor (LR). Lung physiopathology, inflammation, oxidative stress, viral replication, and TLR4/NF-κB/Toll-interacting protein (Tollip) pathway in lung tissue and/or PMVECs were investigated. EGCG attenuated lung histological lesions, decreased lung W/D ratio, cytokines levels, and inhibited MPO activity and prolonged mouse survival. EGCG treatment also markedly downregulated TLR4 and NF-κB protein levels but Tollip expression was upregulated compared with that in untreated H9N2-infected mice (P < 0.05). In PMVECs, anti-67LR antibody treatment significantly downregulated Tollip levels; however, the TLR4 and NF-κB protein levels dramatically increased compared with that in the EGCG-treated group (P < 0.05). EGCG remarkably downregulated TLR4 protein levels through 67LR/Tollip, decreased MPO activity and inflammatory cytokine levels, supporting EGCG as a potential therapeutic agent for managing acute lung injury induced by H9N2 SIV.     

Protective role of liriodendrin in mice with dextran sulphate sodium-induced ulcerative colitis

Sargentodoxa cuneata, containing syringaresinol and its glycoside liriodendrin as the main bioactive compounds, is a well-known traditional Chinese medicine for treating intestinal inflammation. In our preliminary study, liriodendrin inhibited NF-kB activation in sepsis-induced acute lung injury. The present study was designed to investigate its effect on dextran sulfate sodium (DSS)-induced colitis in a mouse model and to explore the possible related mechanisms. Experimental colitis was established by giving mice drinking water containing 3% (w/v) DSS for 7 days. The mice were pretreated with liriodendrin (100 mg/kg/day, intragastrically) 3 days before DSS treatment. We determined the effects of liriodendrin on disease activity index (DAI), colon length, histopathological examination, antioxidants, and anti-inflammatory activities. Our results showed that liriodendrin greatly decreased MPO and MDA activities and significantly increased SOD and GPx activities in the colon. Moreover, liriodendrin improved DAI, colon length and histological damage in colon and reduced the levels of pro-inflammatory cytokines, such as TNF-a, IL-1β and IL-6. Meanwhile, assessments by western blot revealed that liriodendrin significantly suppressed the activation of Akt and NF-κB pathways and up-regulated the expression of ERβ in the colon. In vitro, liriodendrin down-regulated production of pro-inflammatory cytokines and suppressed NF-κB signalling pathways in LPS-induced RAW 264.7 macrophages in a concentration-dependent manner. In addition, syringaresinol, the hydrolysate of liriodendrin, more potently down-regulated production of pro-inflammatory cytokines and suppressed NF-κB and Akt signalling pathways in LPS-induced RAW 264.7 macrophages,which were abolished by using a pure ER antagonist, ICI182, 780. Taken together, liriodendrin-mediated suppression of inflammatory damage in the colon may be attributable to the in vivo transformation to syringaresinol and liriodendrin may be a promising therapeutic approach preventive agent for colitis treatment.     

Ghrelin inhibits interleukin-8 production induced by hydrogen peroxide in A549 cells via NF-κB pathway

Ghrelin, a novel growth hormone-releasing peptide, can influence appetite and induce positive energy balances. Previous studies have reported that ghrelin ameliorated inflammatory responses of the heart, liver and pancreas. We examined whether ghrelin inhibits the proinflammatory cytokine interleukin-8 production induced by hydrogen peroxide (H₂O₂) in human lung epithelia cell line A549 and which mechanism is related with this effect of ghrelin. A549 cells were preincubated with vehicle or ghrelin (0.1 to 1000 ng/mL) in a concentration-dependent manner and then H₂O₂ (0 to 50 μM) was added. The interleukin-8 released by A549 in the medium was determined by ELISA, the mRNA expressions of interleukin-8 and ghrelin receptor were detected by RT-PCR. We also examined the phosphorylation of NF-κB/p65 protein and the degradation of inhibitory protein-κB (I-κB) in A549 by western blot analysis, the NF-κB DNA-binding activity by electrophoretic mobility shift assay, and then detected the generation of reactive oxygen species (ROS) in A549 by nitroblue tetrazolium reduction assay. Cells treated with H₂O₂ (50 μM) exhibited significantly higher interleukin-8 production and ghrelin receptor mRNA expression compared with cells treated with vehicle alone (P < 0.05). Ghrelin inhibited H₂O₂-induced interleukin-8 production by A549 at both mRNA and protein levels in a concentration-dependent manner (P < 0.05). Moreover, ghrelin attenuated H₂O₂-triggered NF-κB activation dependent on I-κB degradation dose-dependently in A549, but the intracellular ROS level after application of H₂O₂ was not affected by ghrelin (1000 ng/mL). Together, these results suggest that ghrelin inhibits H₂O₂-induced interleukin-8 production in A549 cells by targeting on NF-κB pathway, but not by directly scavenging intracellular ROS.     

NecroX-5 alleviate lipopolysaccharide-induced acute respiratory distress syndrome by inhibiting TXNIP/NLRP3 and NF-κB

The activation of NLRP3 inflammasome and NF-κB pathway, associating with oxidative stress, have been implicated in the development of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). NecroX-5 has been reported to exhibit the effects of anti-oxidation and anti-stress in various diseases. However, the role of NecroX-5 in ALI has not been explicitly demonstrated. The aim of this study was to explore the therapeutic effects and potential mechanism action of NecroX-5 on ALI. Here, we found that NecroX-5 pretreatment dramatically diminished the levels of IL-1β, IL-18 and ROS in in RAW264.7 cells challenged with LPS and ATP. Furthermore, NecroX-5 suppressed the activation of NLRP3 inflammasome and NF-κB signal pathway. In addition, NecroX-5 also inhibited the thioredoxin-interacting protein (TXNIP) expression. In vivo, NecroX-5 reduced the LPS-induced lung histopathological injury, the number of TUNEL-positive cells, lung wet/dry (W/D) ratio, levels of total protein and inflammatory cytokines in the bronchoalveolar lavage fluid (BALF) in mice. Additionally, LPS-induced upregulation of myeloperoxidase (MPO), ROS production and malondialdehyde (MDA) were inhibited by NecroX-5 administration. Thus, our results demonstrate that NecroX-5 protects against LPS-induced ALI by inhibiting TXNIP/NLRP3 and NF-κB.     

Silver nanoparticles induced changes in the expression of NF-κB related genes are cell type specific and related to the basal activity of NF-κB

Silver nanoparticles (AgNPs) are widely used in industry and medicine but the recent evidence for their cytotoxicity rise a concern about the safety of their use. We have previously shown that human A549 cells are resistant to AgNPs cytotoxicity, as compared with similarly treated HepG2 cells. In order to check for the role of the NF-κB signaling pathway in response of A549 and HepG2 cell lines to the treatment with 20 nm and 200 nm AgNps, we analyzed the expression of 84 key genes related to the functionality of the NF-κB signaling pathway. We observed considerable alternations in gene expression in HepG2 cells treated with 20 nm AgNPs, and minor changes when exposed to 200 nm AgNPs. Surprisingly, no changes in gene expression were observed in A549 cells treated with both size AgNPs. Using the NF-κB luciferase reporter system, we further tested the basal activity and inducibility of the NF-κB pathway in both cell lines and found that the inducibility of NF-κB signaling in A549 cells is approximately 5 times lower than this of HepG2 cells, but the basal activity is approximately 3.5 times higher. In accordance, the NF-κB activation after AgNPs treatment was observed in HepG2 but not in A549. Altogether indicate that NF-kB mediated cellular response to AgNPs is cell type specific and related to the basal activity of NF-κB.     

Alpha-Mangostin protects rat articular chondrocytes against IL-1β-induced inflammation and slows the progression of osteoarthritis in a rat model

Osteoarthritis (OA) is a joint disease characterized by inflammation and cartilage degradation. α-Mangostin (α-MG), which can be isolated from the fruit of the tropical evergreen tree Garcinia mangostana-L, is known to have anti-inflammatory properties. The aim of the study was to investigate the use of α-MG in the treatment of OA, using both rat chondrocytes and an OA rat model induced by destabilization of the medial meniscus (DMM). Rat chondrocytes were pretreated with α-MG (0, 1.25, 2.5, and 5.0 μg/ml for 24 h) prior to stimulation with interleukin-1β (IL-1β) (10 ng/ml for 24 h). Nitric oxide (NO) production was determined using the Griess method and prostaglandin E₂ (PGE₂) was assessed using an enzyme-linked immunosorbent assay (ELISA). The expression of inducible nitric oxide synthase (INOS), cyclooxygenase-2 (COX-2), matrix metalloproteinase-3, -9, and -13 (MMP-3, MMP-9, and MMP-13), Collagen II, and Aggrecan were detected by both quantitative real-time PCR (qRT-PCR) and a western blot analysis. Nuclear factor-κB (NF-κB) signaling molecules were detected by western blot analysis. Detection of p65 nuclear translocation of NF-κB was examined using immunofluorescence staining. The OA rats received intraperitoneal injections of α-MG (10 mg/kg) or saline every other day. Hematoxylin and eosin and Safranin-O-Fast green staining were used to evaluate the severity of cartilage lesions up to 8 weeks following surgery. α-MG inhibited the production of NO and PGE₂. The elevated expression of INOS, COX-2, MMP-3, MMP-9, and MMP-13, and the degradation of Collagen II and Aggrecan, were reversed by α-MG in IL-1β-stimulated chondrocytes. In addition, IL-1β induced considerable phosphorylation of the NF-kB signaling pathway, which was inhibited by α-MG. Furthermore, the immunofluorescence staining demonstrated that α-MG could suppress IL-1β-induced p65 nuclear translocation. In vivo, cartilage treated with α-MG showed attenuated degeneration and had low Osteoarthritis Research Society International (OARSI) scores compared with the control group. Taken together, these results show that α-MG has potential therapeutic value in the treatment of OA.     

Sodium butyrate inhibits the NF-kappa B signaling pathway and histone deacetylation,and attenuates experimental colitis in an IL-10 independent manner

Butyrate is a bacterial metabolite of dietary fiber in the colon that has been used to treat inflammatory disease. However, the effect of oral supplementation with butyrate on colitis has not been fully explored. We evaluated the effects of and mechanisms underlying oral supplementation with butyrate on experimental murine colitis. In an in vitro study, we found that LPS induced the secretion of cytokines (i.e., IL-8 in COLO 205; TNF-α, IL-6, IL-12, and IL-10 in RAW 264.7; and TNF-α, IL-6 and IL-12 in peritoneal macrophages obtained from IL-10-deficient [IL-10^−/−] mice). Butyrate (100 μM and 500 μM) inhibited pro-inflammatory cytokine production (i.e., IL-8 in COLO205 and TNF-α, IL-6 and IL-12 in macrophages) but promoted anti-inflammatory cytokine (i.e., IL-10) production in RAW264.7 cells. Butyrate attenuated both the LPS-induced degradation/phosphorylation of IκBα and DNA binding of NF-κB and enhanced histone H3 acetylation. To confirm that butyrate played a protective role in colitis, an acute colitis model was induced using dextran sulfate sodium (DSS) and a chronic colitis model was induced in IL-10^−/− mice. The administration of oral butyrate (100 mg/kg) significantly improved histological scores in both colitis models, including the IL-10^−/− mice. In immunohistochemical staining, IκBα phosphorylation was attenuated, and histone H3 acetylation was reversed in the treated colons of both colitis models. Our results indicate that oral supplementation with butyrate attenuates experimental murine colitis by blocking NF-κB signaling and reverses histone acetylation. These anti-colitic effects of butyrate were IL-10-independent. Butyrate may therefore be a therapeutic agent for colitis.     

Anti-inflammatory effect of corymbocoumarin from Seseli gummiferum subsp. corymbosum through suppression of NF-κB signaling pathway and induction of HO-1 expression in LPS-stimulated RAW 264.7 cells

This study investigated the anti-inflammatory activity of corymbocoumarin, an angular-type pyranocoumarin isolated from Seseli gummiferum subsp. corymbosum in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Corymbocoumarin not only inhibited the production of nitric oxide (NO) and prostaglandin E₂ (PGE₂), but also inhibited the protein and mRNA expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Corymbocoumarin also attenuated pro-inflammatory cytokine tumor necrosis factor-α (TNF-α). Investigation of the effect on nuclear factor κB (NF-κB) signaling pathway showed that corymbocoumarin inhibited the phosphorylation of Akt and inhibitory κB (IκB)-α and decreased the subsequent translocation of the p65 and p50 NF-κB subunits to the nucleus. A further study revealed that corymbocoumarin exerted anti-inflammatory activity through induction of heme oxygenase (HO)-1 expression. The in vivo study showed that corymbocoumarin (20 mg/kg, i.p.) reduced paw swelling in carrageenan-induced acute inflammation model. Taken together, these results suggest that corymbocoumarin exerts its anti-inflammatory effect in LPS-stimulated RAW 264.7 cells by suppressing NF-κB activation and inducing HO-1 expression. Corymbocoumarin may provide a useful therapeutic approach for inflammation-associated diseases.     

Protective effect of linalool against lipopolysaccharide/d-galactosamine-induced liver injury in mice

Linalool, a natural compound of the essential oils, has been shown to have antinociceptive, antimicrobial, and anti-inflammatory properties. The aim of this study was to investigate the effects of linalool against lipopolysaccharide (LPS)/d-galactosamine (GalN)-induced liver injury in mice. Mice were administered with linalool 1 h before receiving LPS (50 μg/kg) and GalN (800 mg/kg). The results demonstrated that linalool had a protective effect on LPS/GalN-induced acute liver injury, as evidenced by the attenuation of hepatic pathological damage, malondialdehyde (MDA) content, MPO activity and serum ALT and AST levels. Linalool alleviated serum and hepatic TNF-α and IL-6 production, as well as hepatic iNOS and COX-2 expression by inhibiting NF-κB activation. Treatment of linalool increased bcl-2 expression and inhibited caspase-3 and caspase-8 expression. In addition, linalool increased Nrf2 and heme oxygenase-1 expression up-regulation by LPS/GalN. In conclusion, our results suggested that linalool was protected against LPS/GalN-induced liver injury through induction of antioxidant defense via Nrf2 activating and reduction inflammatory response via NF-κB inhibition.     

β-Glucan modulates the lipopolysaccharide-induced innate immune response in rat mammary epithelial cells

Mastitis, caused by mammary pathogenic bacteria which are frequent implications of Escherichia coli, is an important disease affecting women and dairy animals worldwide. The β-glucan binding of dectin-1 can induce its own intracellular signaling and can mediate a variety of cellular responses. This work was to investigate the effect of β-glucan on the lipopolysaccharide (LPS)-induced in?ammatory response and related innate immune signaling in primary rat mammary epithelial cells. Cells were treated with serum-free medium added with a DMSO solution containing β-glucans at concentrations of 0, 1, 5, 25 μmol/L for 12 h, and then exposed to 10 μg/mL LPS for 40 min. Moreover, cells were pretreated with BAY 11-7082 to inhibit NF-κB and then successively exposed to 5 μmol/L β-glucan, 10 μg/mL LPS, 5 μmol/L β-glucan and 10 μg/mL LPS, according to the specific experimental design. Normal control cultures contained an equal volume of DMSO, which was collected at the same time. After incubating rat mammary epithelial cells for 40 min with 10 μg/mL LPS, TLR4, MyD88 and NF-κB expression all increased (P < 0.05), as did the secretion of TNF-α and IL-1β (P < 0.05), but IκB and β-casein expression both decreased (P < 0.05). Treatment with different concentrations of β-glucan for 12 h activated Dectin1/Syk, which subsequently suppressed TLR4, MyD88 and NF-κB expression and TNF-α and IL-1β secretion. However, it restored the IκB and β-casein expression that had been induced by the 40 min incubation with 10 μg/mL LPS. Pretreatment with BAY 11-7082 at 10 µmol/L for 2 h partially prevented NF-κB induction by LPS, but the presence of β-glucan prevented this inactivation. BAY 11-7082 could not simultaneously inhibit LPS induction of TLR4, MyD88 and β-glucan activation of Dectin1/Syk in rat mammary epithelial cells. These findings demonstrated that β-glucan activation of Dectin1/Syk attenuated LPS induction of TLR4/MyD88/NF-κB and inhibited the LPS-induced inflammation factors in mammary epithelial cells, thereby providing a possibly protective effect of β-glucan in the prevention of LPS-induced dysfunction in mammary epithelial cells.     

Calea uniflora Less. attenuates the inflammatory response to carrageenan-induced pleurisy in mice

Calea uniflora Less. (family Asteraceae), also named “arnica” and “erva-de-lagarto”, is a native plant to the South and Southeast of Brazil. This species was used to treat rheumatism, respiratory diseases, and digestive problems in Brazilian folk medicine. In vitro studies have shown the important biological effects of C. uniflora. However no studies have focused on the mechanism of action of anti-inflammatory activity of C. uniflora. The aim of this study was to evaluate the anti-inflammatory effects of the crude extract, its fractions, and isolated compounds obtained from of C. uniflora, using mouse model of carrageenan-induced inflammation. The following inflammatory parameters: leukocyte influx, degree of exudation, myeloperoxidase (MPO) and adenosine deaminase (ADA) activities, nitric oxide metabolites (NOx), proinflammatory cytokines and phosphorylation of the p65 subunit of NF-κB (p-p65 NF-κB), and p38 mitogen-activated protein kinase (p-p38 MAPK) levels were determined. The crude extract of C. uniflora, its fractions and its isolated compounds reduced the leukocyte influx, degree of exudation, MPO and ADA activities, NOx, TNF-α, IFN-γ, MCP-1 and IL-6 levels (p < 0.05). The isolated compounds reduced p-p65 NF-κB and p-p38 MAPK levels (p < 0.01). This study demonstrated that C. uniflora exhibits a significant anti-inflammatory activity via inhibition of the leukocyte influx and degree of exudation. These effects were associated with a decrease in the levels of several proinflammatory mediators. The mechanism of the anti-inflammatory action of C. uniflora may be, at least in part, via the inhibition of p65 NF-κB and p38 MAPK activation by the isolated compounds.     

Genipin alleviates LPS-induced acute lung injury by inhibiting NF-κB and NLRP3 signaling pathways

Genipin has been reported to have anti-inflammatory effect. However, its role on lipopolysaccharide (LPS)-induced acute lung injury (ALI) has not been explored. This study aimed to evaluate the effect of genipin on murine model of acute lung injury induced by LPS. The mice were treated with genipin 1 h before LPS administration. 12 h later, the myeloperoxidase (MPO) in lung tissues and lung wet/dry ratio were detected. The levels of TNF-α, IL-1β and IL-6 in bronchoalveolar lavage fluid (BALF) were measured by ELISA. Apart from this, we use western blot to detect the protein expression in the NF-κB and NLRP3 signaling pathways. The results showed that the treatment of genipin markedly attenuated the lung wet/dry ratio and the MPO activity. Moreover, it also inhibited the levels of TNF-α, IL-1β, IL-6 in the BALF. In addition, genipin significantly inhibited LPS-induced NF-κB and NLRP3 activation. In conclusion, these results demonstrate that genipin protected against LPS-induced ALI through inhibiting NF-κB and NLRP3 signaling pathways.     

Protective effect of Lactobacillus plantarum 21, a probiotic on trinitrobenzenesulfonic acid-induced ulcerative colitis in rats

Inflammatory mediators play a crucial role in ulcerative colitis (UC). The present study was aimed to evaluate the effects of Lactobacillus plantarum 21 (LAB 21) on inflammatory mediators in trinitrobenzenesulfonic acid (TNBS)-induced colitis in rats. The inflammatory response was assessed by changes in colon morphology, histopathology, and measurement of reduced glutathione (GSH), lipid peroxidation (TBARS), nitric oxide (NO), interleukin 1β (IL-1β), tumor necrosis factor α (TNF-α), and interleukin 10 (IL-10) mRNA and protein levels by ELISA. Besides, protein expressions of IL-1β and IL-10 were also evaluated by western blot. Treatment with LAB 21 (1 × 10¹⁰ CFU/rat/day) and sulfasalazine (500 mg kg^− 1 body weight) for 14 days after induction of colitis, significantly decreased TBARS, NO and increased GSH concentration. The protein and mRNA expressions of IL-1β and TNFα were down-regulated, whereas, protein and mRNA expression of IL-10 was up-regulated in LAB 21-treated rats. Moreover, LAB 21 attenuated the macroscopic colonic damage, histopathological changes induced by TNBS. These results suggest that LAB 21 may be effective in the treatment of UC by immunomodulatory and antioxidant properties.