OBJECTIVE: To identify the underlying mechanism by which quercetin (Que) alleviates sepsis-related acute respiratory distress syndrome (ARDS). METHODS: In vivo, C57BL/6 mice were assigned to sham, cecal ligation and puncture (CLP), and CLP+Que (50 mg/kg) groups (n=15 per group) by using a random number table. The sepsisrelated ARDS mouse model was established using the CLP method. In vitro, the murine alveolar macrophages (MH-S) cells were classified into control, lipopolysaccharide (LPS), LPS+Que (10 μmol/L), and LPS+Que+acetylcysteine (NAC, 5 mmol/L) groups. The effect of Que on oxidative stress, inflammation, and apoptosis in mice lungs and MH-S cells was determined, and the mechanism with reactive oxygen species (ROS)/p38 mitogen-activated protein kinase (MAPK) pathway was also explored both in vivo and in vitro. RESULTS: Que alleviated lung injury in mice, as reflected by a reversal of pulmonary histopathologic changes as well as a reduction in lung wet/dry weight ratio and neutrophil infiltration (P<0.05 or P<0.01). Additionally, Que improved the survival rate and relieved gas exchange impairment in mice (P<0.01). Que treatment also remarkedly reduced malondialdehyde formation, superoxide dismutase and catalase depletion, and cell apoptosis both in vivo and in vitro (P<0.05 or P<0.01). Moreover, Que treatment diminished the release of inflammatory factors interleukin (IL)-1β, tumor necrosis factor-α, and IL-6 both in vivo and in vitro (P<0.05 or P<0.01). Mechanistic investigation clarifified that Que administration led to a decline in the phosphorylation of p38 MAPK in addition to the suppression of ROS expression (P<0.01). Furthermore, in LPS-induced MH-S cells, ROS inhibitor NAC further inhibited ROS/p38 MAPK pathway, as well as oxidative stress, inflammation, and cell apoptosis on the basis of Que treatment (P<0.05 or P<0.01). CONCLUSION Que was found to exert anti-oxidative, anti-inflammatory, and anti-apoptotic effects by suppressing the ROS/p38 MAPK pathway, thereby conferring protection for mice against sepsis-related ARDS.
Animals ; Sepsis/drug therapy* ; Quercetin/therapeutic use* ; Respiratory Distress Syndrome/enzymology* ; p38 Mitogen-Activated Protein Kinases/metabolism* ; Mice, Inbred C57BL ; Reactive Oxygen Species/metabolism* ; Apoptosis/drug effects* ; Male ; Oxidative Stress/drug effects* ; MAP Kinase Signaling System/drug effects* ; Lung/drug effects* ; Mice ; Lipopolysaccharides ; Macrophages, Alveolar/pathology* ; Inflammation/pathology* ; Protective Agents/therapeutic use*

Iron deficiency anemia is one of the most common micronutrient deficient conditions around the globe with various consequences, including the weakened immune system. Quercetin is widely distributed bioflavonoid; it has been debated for its dual roles in iron regulation. Quercetin-iron interaction in the body is a complex mechanism which has not been completely understood. The present study aimed to investigate the effect of quercetin on iron supplementation in iron deficiency anemia and on iNOS expression in splenic macrophages. The rat model of iron deficiency anemia was induced by feeding low iron diet to weanling rats for 20 days. The animals were then administered with ferrous sulfate, quercetin, and their combination for 30 days. Blood parameters, histopathological analysis, iron storage, CD68, iNOS and SLC40 expression in rat spleen were investigated. Our results showed that quercetin regulated iron absorption, despite SLC40 down-expression, indicating possible alternate route of iron transport, and that quercetin modulated iNOS production in splenic macrophages.
Anemia, Iron-Deficiency ; drug therapy ; genetics ; metabolism ; Animals ; Dietary Supplements ; analysis ; Female ; Homeostasis ; drug effects ; Humans ; Iron ; deficiency ; Macrophages ; drug effects ; metabolism ; Nitric Oxide Synthase Type II ; genetics ; metabolism ; Quercetin ; administration & dosage ; Rats ; Rats, Sprague-Dawley ; Spleen ; drug effects ; enzymology

Dendrobii Caulis (DC), named 'Shihu' in Chinese, is a precious herb in traditional Chinese medicine. It is widely used to nourish stomach, enhance body fluid production, tonify "Yin" and reduce heat. More than thirty Dendrobium species are used as folk medicine. Some compounds from DC exhibit inhibitory effects on macrophage inflammation. In the present study, we compared the anti-inflammatory effects among eight Dendrobium species. The results provided evidences to support Dendrobium as folk medicine, which exerted its medicinal function partially by its inhibitory effects on inflammation. To investigate the anti-inflammatory effect of Dendrobium species, mouse macrophage cell line RAW264.7 was activated by lipopolysaccharide. The nitric oxide (NO) level was measured using Griess reagent while the pro-inflammatory cytokines were tested by ELISA. The protein expressions of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2) and mitogen-activated protein kinases (MAPKs) phosphorylation were evaluated by Western blotting analysis. Among the eight Dendrobium species, both water extracts of D. thyrsiflorum B.S.Williams (DTW) and D. chrysotoxum Lindl (DCHW) showed most significant inhibitory effects on NO production in a concentration-dependent manner. DTW also significantly reduced TNF-α, MCP-1, and IL-6 production. Further investigations showed that DTW suppressed iNOS and COX-2 expression as well as ERK and JNK phosphorylation, suggesting that the inhibitory effects of DTW on LPS-induced macrophage inflammation was through the suppression of MAPK pathways. In conclusion, D. thyrsiflorum B.S.Williams was demonstrated to have potential to be used as alternative or adjuvant therapy for inflammation.
Animals ; Anti-Inflammatory Agents ; pharmacology ; Cyclooxygenase 2 ; genetics ; Cytokines ; metabolism ; Dendrobium ; chemistry ; Gene Expression Regulation, Enzymologic ; drug effects ; Inflammation ; chemically induced ; drug therapy ; Lipopolysaccharides ; Macrophages ; drug effects ; enzymology ; Mice ; Mitogen-Activated Protein Kinases ; antagonists & inhibitors ; genetics ; metabolism ; Nitric Oxide ; analysis ; Nitric Oxide Synthase Type II ; genetics ; Phosphorylation ; drug effects ; Plant Extracts ; pharmacology ; RAW 264.7 Cells ; Signal Transduction ; drug effects

We investigated whether Nd2O3 treatment results in cytotoxicity and other underlying effects in rat NR8383 alveolar macrophages. Cell viability assessed by the MTT assay revealed that Nd2O3 was toxic in a dose-dependent manner, but not in a time-dependent manner. An ELISA analysis indicated that exposure to Nd2O3 caused cell damage and enhanced synthesis and release of inflammatory chemokines. A Western blot analysis showed that protein expression levels of caspase-3, nuclear factor-κB (NF-κB) and its inhibitor IκB increased significantly in response to Nd2O3 treatment. Both NF-κB and caspase-3 signaling were activated, suggesting that both pathways are involved in Nd2O3 cytotoxicity.
Animals ; Caspase 3 ; metabolism ; Cell Line ; Macrophages, Alveolar ; drug effects ; enzymology ; NF-kappa B ; metabolism ; Neodymium ; toxicity ; Oxides ; toxicity ; Rats ; Toxicity Tests

OBJECTIVETo study the effects of Kangai injection on the enzyme activities of macrophages and morphology of spleen and thymus from rats.

METHODSTwenty four male SD rats were randomly divided into two groups (n = 12), normal control group and experimental group. The rats in experimental group were injected with Kangai injection at the dosage of 5 ml/kg x d for 30 days peritoneally and those in control group were injected with nomal saline at the same volume. The content of supermicro protein was assayed by BCA method, the activities of lactate dehydrogenase (LDH), glutathione peroxidase(GSH-Px), and inducible nitric oxide synthase (iNOS) from alveolar macrophages(AM) and peritoneal macrophages (PM) were detected biochemically. The activities of acid phosphatase (ACP), superoxide dismutase(SOD) and succinate dehydrogenase (SDH) from AM and PM were detected by ELISA. The morphology of spleen and thymus were observed by light microscopy.

RESULTSThe activities of LDH, GSH-Px and iNOS within AM and PM from experimental group were increased significantly compared with those of control group (P < 0.05). The activities of ACP, SOD and SDH in AM and PM from experimental group were also higher than those from control group (P < 0.05). Microscopically, there was thickening of peripheral arterial lymphatic sheath, enlargement of splenic lymphoid nodules with expended germinal center in the spleen of experimental group. There was no significant difference in the mophology of thymus between the two groups.

CONCLUSIONKangai injection may improve immune function by activating macrophages.

Animals ; Drugs, Chinese Herbal ; pharmacology ; Glutathione Peroxidase ; metabolism ; L-Lactate Dehydrogenase ; metabolism ; Macrophages ; drug effects ; enzymology ; Male ; Nitric Oxide Synthase Type II ; metabolism ; Rats ; Rats, Sprague-Dawley ; Succinate Dehydrogenase ; metabolism ; Superoxide Dismutase ; metabolism

Wnt5a is a ligand that activates the noncanonical Wnt signaling pathways (beta-catenin-independent pathways). Human neutrophils expressed several Wnt5a receptors, such as Frizzled 2, 5 and 8. Stimulation of human neutrophils with Wnt5a caused chemotactic migration and the production of two important chemokines, CXCL8 and CCL2. CCL2 production by Wnt5a was mediated by a pertussis toxin-sensitive G-protein-dependent pathway. Wnt5a also stimulated the phosphorylation of three mitogen-activated protein kinases (MAPKs: ERK, p38 MAPK and JNK) and Akt. Inhibition of ERK, p38 MAPK or JNK by specific inhibitors induced a dramatic reduction in Wnt5a-induced CCL2 production. Supernatant collected from lipopolysaccharide-stimulated macrophages induced neutrophil chemotaxis, which was significantly inhibited by anti-Wnt5a antibody. Our results suggested that Wnt5a may contribute to neutrophil recruitment, mediating the inflammation response.
Activating Transcription Factor 2/metabolism ; Animals ; Cell Separation ; Chemokines/*biosynthesis ; Chemotaxis/*drug effects ; Culture Media, Conditioned/pharmacology ; Extracellular Signal-Regulated MAP Kinases/metabolism ; GTP-Binding Proteins/metabolism ; Humans ; JNK Mitogen-Activated Protein Kinases/metabolism ; Lipopolysaccharides/pharmacology ; Macrophages/drug effects/metabolism ; Mice ; NF-kappa B/metabolism ; Neutrophils/*cytology/drug effects/enzymology/*metabolism ; Pertussis Toxin/pharmacology ; Phosphatidylinositol 3-Kinases/metabolism ; Proto-Oncogene Proteins c-akt/metabolism ; Receptors, Wnt/metabolism ; Type C Phospholipases/metabolism ; Wnt Proteins/*pharmacology ; p38 Mitogen-Activated Protein Kinases/metabolism

Recent studies have documented that Janus-activated kinase (JAK)-signal transducer and activator of transcription (STAT) pathway can modulate the apoptotic program in a myocardial ischemia/reperfusion (I/R) model. To date, however, limited studies have examined the role of JAK3 on myocardial I/R injury. Here, we investigated the potential effects of pharmacological JAK3 inhibition with JANEX-1 in a myocardial I/R model. Mice were subjected to 45 min of ischemia followed by varying periods of reperfusion. JANEX-1 was injected 1 h before ischemia by intraperitoneal injection. Treatment with JANEX-1 significantly decreased plasma creatine kinase and lactate dehydrogenase activities, reduced infarct size, reversed I/R-induced functional deterioration of the myocardium and reduced myocardial apoptosis. Histological analysis revealed an increase in neutrophil and macrophage infiltration within the infarcted area, which was markedly reduced by JANEX-1 treatment. In parallel, in in vitro studies where neutrophils and macrophages were treated with JANEX-1 or isolated from JAK3 knockout mice, there was an impairment in the migration potential toward interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1), respectively. Of note, however, JANEX-1 did not affect the expression of IL-8 and MCP-1 in the myocardium. The pharmacological inhibition of JAK3 might represent an effective approach to reduce inflammation-mediated apoptotic damage initiated by myocardial I/R injury.
Animals ; Apoptosis/drug effects ; Cell Movement/drug effects ; Chemokines/pharmacology ; Heart Function Tests/drug effects ; Inflammation/pathology ; Janus Kinase 3/*antagonists & inhibitors/metabolism ; Macrophages/drug effects/metabolism/pathology ; Male ; Mice ; Mice, Inbred C57BL ; Myocardial Reperfusion Injury/drug therapy/*enzymology/physiopathology/*prevention & control ; Myocardium/enzymology/pathology ; Myocytes, Cardiac/drug effects/metabolism/pathology ; Neutrophils/drug effects/metabolism/pathology ; Quinazolines/pharmacology/therapeutic use

BACKGROUNDLipoprotein-associated phospholipase A2 (Lp-PLA2) is mainly secreted by macrophages, serving as a specific marker of atherosclerotic plaque and exerting pro-atherogenic effects. It is known that high-density lipoprotein (HDL) plays an important role against atherosclerosis by inhibiting pro-inflammatory factors, however, the relationship between HDL and Lp-PLA2 remains elusive.

METHODSIn this study, reverse transcription-polymerase chain reaction (RT-PCR), Western blotting, and a platelet-activating factor (PAF) acetylhydrolase assay were performed to determine the Lp-PLA2 mRNA level, protein expression and activity in human monocyte-derived macrophages upon HDL treatment of different concentrations and durations. To investigate the underlying mechanism of HDL-induced Lp-PLA2 action, pioglitazone, a peroxisome proliferator-activated receptor-γ (PPARγ) ligand, was introduced to human monocyte-derived macrophages and mRNA and protein levels of Lp-PLA2, as well as its activity, were determined.

RESULTSLp-PLA2 mRNA levels, protein expression and activity were significantly inhibited in response to HDL treatment in a dose and time dependent manner in human monocyte-derived macrophages. Pioglitazone treatment (1 - 10 ng/ml) upregulated the Lp-PLA2 mRNA level, protein expression and activity in human monocyte-derived macrophages, while the effects were markedly reversed by HDL. In addition, pioglitazone resulted in a significant increase in PPARγ phosphorylation in human monocyte-derived macrophages, which could be inhibited by HDL.

CONCLUSIONThese findings indicate that HDL suppresses the expression and activity of Lp-PLA2 in human monocyte-derived macrophages, and the underlying mechanisms may be mediated through the PPARγ pathway.

1-Alkyl-2-acetylglycerophosphocholine Esterase ; genetics ; metabolism ; Cells, Cultured ; Humans ; Lipoproteins, HDL ; pharmacology ; Macrophages ; drug effects ; enzymology ; metabolism ; PPAR gamma ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Signal Transduction ; drug effects ; genetics

OBJECTIVETo observe the effect of andrographolide on the activation of mitogen-activated protein kinases (MAPKs) and expression of nuclear factor-κB (NF-κB) in macrophage foam cells.

METHODSThe mouse peritoneal macrophages were cultured in the media in the presence of oxidized low-density lipoprotein (ox-LDL), ox-LDL+andrographolide, or neither (control). The phosphorylation of MAPK molecules (p38MAPK, JNK, ERK1/2) and the expressions of NK-κB p65 were examined by Western blot.

RESULTSAs compared with cells in the control group, the expressions of phospho-p38 and NF-κB p65 were increased in the cells cultured with either ox-LDL or ox-LDL+andrographolide (P<0.01), but attenuated significantly in the presence of ox-LDL+ andrographolide when compared with ox-LDL (P<0.05). The phospho-JNK increased in the presence of either ox-LDL or ox-LDL+andrographolide when compared with control cells (P<0.01), but no significant difference existed between ox-LDL and ox-LDL+andrographolide (P>0.05). The expression of phospho-ERK1/2 was increased in the presence of ox-LDL compared with the control cells (P<0.01), but no significant differences existed between the cells cultured in the presence of ox-LDL+andrographolide and the control medium (P>0.05).

CONCLUSIONSAndrographolide could inhibit the activation of ERK1/2, p38MAPK and NK-κB induced by ox-LDL in macrophage foam cells, which might be one of its mechanisms in preventing atherosclerosis.

Animals ; Anti-Inflammatory Agents ; pharmacology ; Atherosclerosis ; immunology ; metabolism ; prevention & control ; Cells, Cultured ; Diterpenes ; pharmacology ; Extracellular Signal-Regulated MAP Kinases ; metabolism ; Foam Cells ; cytology ; drug effects ; enzymology ; JNK Mitogen-Activated Protein Kinases ; metabolism ; Lipoproteins, LDL ; metabolism ; MAP Kinase Signaling System ; drug effects ; immunology ; Macrophages, Peritoneal ; cytology ; drug effects ; enzymology ; Mice ; Mice, Inbred Strains ; NF-kappa B ; metabolism ; Vasculitis ; drug therapy ; immunology ; metabolism ; p38 Mitogen-Activated Protein Kinases ; metabolism

We investigate the role of β-catenin signaling in the response of macrophage to lipopolysaccharide (LPS) using RAW264.7 cells. LPS rapidly stimulated cytosolic β-catenin accumulation. β-catenin-mediated transcription was showed to be required for LPS induced gene expression and cell migration. Mechanically, ERK activation-primed GSK3β inactivation by Akt was demonstrated to mediate the LPS induced β-catenin accumulation. Overall, our findings suggest that suppression of GSK3β by ERK stimulates β-catenin signaling therefore contributes to LPS induced cell migration in macrophage activation.
Animals ; Cell Line ; Cell Movement ; drug effects ; Enzyme Activation ; drug effects ; Extracellular Signal-Regulated MAP Kinases ; metabolism ; Gene Expression Regulation, Enzymologic ; drug effects ; Glycogen Synthase Kinase 3 ; metabolism ; Glycogen Synthase Kinase 3 beta ; Lipopolysaccharides ; pharmacology ; Macrophages ; cytology ; drug effects ; enzymology ; metabolism ; Matrix Metalloproteinase 9 ; genetics ; Mice ; Proto-Oncogene Proteins c-akt ; metabolism ; Signal Transduction ; drug effects ; Transcription, Genetic ; drug effects ; Wnt Proteins ; metabolism ; beta Catenin ; metabolism