Baicalin inhibits APEC-induced lung injury by regulating gut microbiota and SCFA production.

Baicalin is a plant-derived flavonoid from Scutellaria baicalensis Georgi with multiple bioactivities and has a protective effect against avian pathogenic Escherichia coli (APEC) infection. However, the underlying mechanism of baicalin against APEC infection is still unknown. Therefore, we aimed to explore whether the protective effects and mechanisms of baicalin on APEC-induced lung inflammation were related to the regulation of gut microbiota. The results showed that baicalin significantly reduced APEC colonization and pro-inflammatory cytokines production, and additionally recovered air-blood barrier integrity in the lungs after APEC challenge. However, depletion of gut microbiota significantly weakened the protective effects of baicalin against APEC infection as mentioned above. Furthermore, baicalin markedly restored the dysbiosis of gut microbiota induced by APEC as well as increased the abundance of short chain fatty acid (SCFA)-producing bacteria and the production of SCFAs including acetic acid, propionic acid and butyric acid, especially acetic acid. In addition, the concentrations of acetic acid and its receptor free fatty acid receptor 2 (FFAR2) were significantly upregulated in the lung tissues after baicalin treatment. In conclusion, gut microbiota played a key role in the pharmacological action of baicalin against APEC-induced lung inflammation. Baicalin remodeled the dysbiosis of gut microbiota caused by APEC and increased the production of SCFAs, especially acetic acid in the gut, and then the increased acetate may circulate to the lungs to activate FFAR2 to defend APEC infection. Together, our study suggested that baicalin inhibited APEC infection through remodeling the gut microbiota dysbiosis and increasing the SCFA production. Furthermore, baicalin may serve as an alternative antibiotic and a novel therapeutic drug to prevent or treat APEC infection.

Schizandrin attenuates lung lesions induced by Avian pathogenic Escherichia coli in chickens.

Avian pathogenic Escherichia coli (APEC) can cause serious pathological changes and inflammation in chickens. Schizandrin has anti-inflammatory activity and can prevent damage to various tissues and organs. The purpose of this study was to investigate the protective effect of schizandrin on APEC-induced lung lesions in chickens and explore the potential mechanism of schizandrin protection. The schizandrin (50, 100, and 200 mg/kg) was intragastrically administered for 3 days. APEC was administered using intraperitoneal (i.p.) injection to induce lung lesions. Then, chickens were sacrificed by CO2 inhalation 24 h later and the lung tissues were collected for examining histopathological changes, wet/dry (W/D) ratio, myeloperoxidase (MPO) activity, malondialdehyde (MDA), levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, and IL-8 and activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Our findings showed that schizandrin markedly inhibited pathological changes, pulmonary edema, MPO activity and MDA content. Moreover, schizandrin markedly reduced the levels of TNF-α, IL-1ß, IL-6 and IL-8 in lung tissue. Importantly, the mechanism responsible for these effects was attributed to the inhibitory effect of schizandrin on NF-κB and MAPK signaling activation. In conclusion, our findings reveal that schizandrin displays anti-oxidant and anti-inflammatory activity against APEC-induced lung lesions in chickens, paving the way for rational use of schizandrin as a protective agent against lung-related inflammatory disease.

Schizandrin attenuates inflammation induced by avian pathogenic Escherichia coli in chicken type II pneumocytes.

Avian pathogenic Escherichia coli (APEC) is a kind of highly pathogenic parenteral bacteria, which adheres to chicken type II pneumocytes through pili, causing inflammatory damage of chicken type II pneumocytes. Without affecting the growth of bacteria, anti-adhesion to achieve anti-inflammatory effect is considered to be a new method for the treatment of multi-drug-resistant bacterial infections. In this study, the anti-APEC activity of schizandrin was studied in vitro. By establishing the model of chicken type II pneumocytes infected with APEC-O78, the adhesion number, the expression of virulence genes, the release of lactate dehydrogenase (LDH), levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, IL-8 and activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways were detected. The results showed that schizandrin reduced the release of LDH and the adherence of APEC on chicken type II pneumocytes. Moreover, schizandrin markedly decreased the levels of IL-1ß, IL-8, IL-6, and TNF-α, the mechanism responsible for these effects was attributed to the inhibitory effect of schizandrin on NF-κB and MAPK signaling activation. In conclusion, our findings revealed that schizandrin could reduce the inflammatory injury of chicken type II pneumocytes by reducing the adhesion of APEC-O78 to chicken type II pneumocytes. The results indicate that schizandrin can be a potential agent to treat inflammation caused by avian colibacillosis.

Canine distemper virus increased the differentiation of CD4+CD8+ T cells and mRNA expression of inflammatory cytokines in peripheral blood lymphocyte from canine.

BACKGROUND: Canine distemper virus (CDV) can cause a highly contagious disease to canid. However, how CDV affects peripheral blood lymphocyte (PBL) remains unclear. METHODS: In this study, CDV infected PBL was cultured to investigate the effect of CDV on the differentiation of lymphocytes and the mRNA expression of inflammatory cytokines in PBL. RESULTS: The results showed that CDV changed the phenotype of lymphocytes and increased the percentage of CD4+CD8+ T cells. To explore the effect of immune response of lymphocytes to CDV, the mRNA expression of pro- and anti-inflammatory cytokines was examined. Interleukin (IL-6, IL-12B), and tumor necrosis factor (TNF)-α mRNA expression was significantly increased at 12-48 h after CDV infection. IL-10 mRNA expression was dramatically enhanced at 12-36 h after CDV infection. However, IL-4 and transforming growth factor (TGF-ß) were not response to CDV infection. These results indicated that PBL differentiated intoCD4+CD8+ T cells and improved the inflammatory response to CDV infection. CONCLUSIONS: After CDV infection, PBL differentiated into CD4+CD8+ T cells and initiated inflammatory response.

Oroxylin A inhibits H2O2-induced oxidative stress in PC12 cells.

Oroxylin A, a natural flavonoid isolated from Scutellaria baicalensis, has been reported to have anti-inflammatory and antioxidant effects. However, suppression of oxidative stress and neuroapoptosis by oroxylin A is largely uninvestigated. To investigate the protective effects of oroxylin A, PC12 cells were exposed to oroxylin A and hydrogen peroxide solutions and measured. Oroxylin A significantly reduced the levels of intracellular calcium and reactive oxygen species and increased the levels of CAT and Mn/SOD. Oroxylin A also inhibited the activation of caspase-3. These results suggest that treatment of PC12 cells with oroxylin A inhibits H2O2-induced oxidative stress.

Peimine impairs pro-inflammatory cytokine secretion through the inhibition of the activation of NF-κB and MAPK in LPS-induced RAW264.7 macrophages.

In the previous study, we found that peimine has good anti-inflammatory effects in vivo. However, the anti-inflammatory mechanism of peimine remains unclear. We, therefore, assessed the effects of peimine on inflammatory cytokines in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. We found that peimine (0-25 mg/L) significantly inhibited tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1ß, and increased IL-10 production. Furthermore, peimine significantly inhibited the phosphorylation of p38, ERK and c-jun N-terminal kinase (JNK) as well as decreased p65 and IκB. The present results indicate that peimine inhibits the production of inflammatory cytokines induced by LPS through blocking MAPKs and NF-κB signaling pathways.

Inhibitory effects of sulfated 20(S)-ginsenoside Rh2 on the release of pro-inflammatory mediators in LPS-induced RAW 264.7 cells.

Ginsenoside Rh2 is one of the most important ginsenosides in ginseng with anti-inflammatory and antitumor effects. However, the extremely poor oral bioavailability induced by its low water solubility greatly limits the potency of Rh2 in vivo. In the previous study, we sulfated 20(S)-ginsenoside Rh2 with chlorosulfonic acid and pyridine method, and got one novel derivative, Rh2-B1, with higher water solubility and greater immunologic enhancement than Rh2. However, the anti-inflammatory effect of Rh2-B1 remains unclear. We therefore investigated the effects of Rh2-B1 on lipopolysaccharide (LPS)-induced proinflammatory mediators in RAW 264.7 macrophages. We found that Rh2-B1 dramatically inhibited LPS-induced overproduction of nitric oxide, prostaglandin E2, tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and IL-6. Consistently, the protein and mRNA expression levels of inducible nitric oxide synthase and cyclooxygenase-2 were remarkably decreased by Rh2-B1. In addition, Rh2-B1 significantly suppressed the phosphorylations of p38, c-Jun N-terminal kinase, and extracellular signal receptor-activated kinase 1/2 induced by LPS. Rh2-B1 was further shown to inhibit NF-κB p65 translocation into the nucleus by suppressing IκBα degradation. In conclusion, we demonstrate that Rh2-B1 inhibits the release of LPS-induced pro-inflammatory mediators through blocking mitogen-activated protein kinases and NF-κB signaling pathways, suggesting that sulfated ginsenosides could be potential agents for anti-inflammatory therapies.

Sulfated derivatives of 20(S)-ginsenoside Rh2 and their inhibitory effects on LPS-induced inflammatory cytokines and mediators.

Ginsenoside Rh2 is one of the most important ginsenosides in ginseng with antitumor, antidiabetic, antiallergic, and anti-inflammatory effects. However, the extremely poor oral bioavailability induced by its low water solubility greatly limits the potency of Rh2 in clinical use. Therefore, in this study we sulfated 20(S)-ginsenoside Rh2 with chlorosulfonic acid and pyridine method, and got two new sulfated derivatives, Rh2-B1 and Rh2-B2, with higher water solubility. Their chemical structures were characterized by spectroscopic methods (IR, MS and NMR). Additionally, Rh2-B1 and Rh2-B2 had the greater anti-inflammatory effects than Rh2 through inhibiting inflammatory cytokines and mediators in LPS-induced mouse RAW264.7 macrophages cells. These results suggested that the sulfated modification of Rh2 improved its water solubility and the sulfated derivatives could be more potential candidates for developing as anti-inflammatory agents.

Xiang-Qi-Tang and its active components exhibit anti-inflammatory and anticoagulant properties by inhibiting MAPK and NF-κB signaling pathways in LPS-treated rat cardiac microvascular endothelial cells.

Xiang-Qi-Tang (XQT) is a Chinese herbal formula containing Cyperus rotundus, Astragalus membranaceus and Andrographis paniculata. Alpha-Cyperone (CYP), astragaloside IV (AS-IV) and andrographolide (AND) are the three major active components in this formula. XQT may modulate the inflammatory or coagulant responses. We therefore assessed the effects of XQT on lipopolysaccharide (LPS)-induced inflammatory model of rat cardiac microvascular endothelial cells (RCMECs). XQT, CYP, AS-IV and AND inhibited the production of tumor necrosis factor alpha (TNF-α), intercellular cell adhesion molecule-1 (ICAM-1) and plasminogen activator inhibitor-1 (PAI-1), and up-regulated the mRNA expression of Kruppel-like factor 2 (KLF2). XQT and CYP inhibited the secretion of tissue factor (TF). To further explore the mechanism, we found that XQT, or its active components CYP, AS-IV and AND significantly inhibited extracellular signal-regulated kinase (ERK), c-jun NH2-terminal kinase (JNK) and p38 phosphorylation protein expression as well as decreased the phosphorylation levels of nuclear factor κB (NF-κB) p65 proteins in LPS-stimulated RCMECs. These results suggested that XQT and its active components inhibited the expression of inflammatory and coagulant mediators via mitogen-activated protein kinase (MAPKs) and NF-κB signaling pathways. These findings may contribute to future research on the action mechanisms of this formula, as well as therapy for inflammation- or coagulation-related diseases.

Sulfated derivative of 20(S)-ginsenoside Rh2 inhibits inflammatory cytokines through MAPKs and NF-kappa B pathways in LPS-induced RAW264.7 macrophages.

In the previous study, we found that sulfated derivative B2 of ginsenoside Rh2 (Rh2-B2) has greater anti-inflammatory effects than 20(S)-ginsenoside Rh2. However, the anti-inflammatory mechanism of Rh2-B2 remains unclear. We therefore assessed the effects of Rh2-B2 on inflammatory cytokines in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. We found that Rh2-B2 (1-5 mg/L) significantly inhibited tumor necrosis factor alpha, interleukin (IL)-6, IL-1ß, and increased IL-10 production from protein and mRNA levels. Furthermore, Rh2-B2 significantly inhibited the phosphorylation of p38 and c-Jun N-terminal kinase as well as decreased p65 nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) translocation into the nucleus by nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha degradation. The present results indicate that Rh2-B2 inhibits the production of inflammatory cytokines induced by LPS through blocking mitogen-activated protein kinases and NF-κB signaling pathways.

Xiang-qi-tang increases avian pathogenic Escherichia coli-induced survival rate and regulates serum levels of tumor necrosis factor alpha, interleukin-1 and soluble endothelial protein C receptor in chicken.

Xiang-qi-tang (XQT) is a Chinese herbal formula containing rhizoma Cyperi, Andrographis paniculata and Astragalus membranaceus. The present study investigated the effects of XQT on the mortality and inflammatory mediators in a chicken model challenged with avian pathogenic Escherichia coli (APEC). To detect the effect of XQT, the chickens were pretreated with the formula 12 h before being challenged with 10(8) colony forming unit (CFU) of APEC. The results showed that 0.6 g/kg XQT significantly elevated the survival rate of infected chickens. To further investigate the mechanism of decreasing mortality of XQT, we examined plasma inflammatory mediator levels. The levels of tumor necrosis factor alpha (TNF-α), interleukin-1 (IL-1) and soluble endothelial protein C receptor (sEPCR) were significantly increased in chickens challenged with APEC alone, whereas chickens pretreated with 0.6 g/kg XQT showed marked decrease of these inflammatory mediator levels during the death peak. Taken together, this study demonstrates that XQT has protective effects in APEC-treated chickens. The action mechanisms of XQT involve anti-inflammation and antithrombotic activity. These findings may contribute to future research on the action mechanisms of this formula, as well as prevention of or therapy for avian colibacillosis.

Vaspin can not inhibit TNF-alpha-induced inflammation of human umbilical vein endothelial cells.

Visceral adipose tissue-derived serine protease inhibitor (vaspin) has been recently identified as an adipocytokine in a rat model of type 2 diabetes. Adipocytokines may directly influence the function of endothelial cells (ECs) and modulate inflammatory states. We therefore assessed the effects of vaspin on basal and TNF-alpha-stimulated human umbilical vein ECs. Vaspin (10-100 ng/ml, 24 hr) had no effects on both basal ECs morphology and TNF-alpha-induced (10 ng/ml, 24 hr) morphological damages. Vaspin did not inhibit the TNF-alpha (20 min) activation of JNK, p38 and NF-kappaB, but only slightly inhibited Akt. Furthermore, vaspin did not decrease the TNF-alpha (24 hr) induction of vascular cell adhesion molecule-1, intercellular adhesion molecule-1, endothelial selectin, and cyclooxygenase-2 protein expression as well as monocyte chemotactic protein-1, tissue factor, and plasmogen activator inhibitor-1 mRNA expression. The present results indicate that vaspin has no effects on normal ECs, and can not prevent TNF-alpha-induced inflammatory injury.