AIMTo investigate whether formalin inflammatory pain can induce hippocampal neuronal apoptosis of rats or not.

METHODSRats were subcutaneously injected with 0.2 ml 0.5% formalin into the ventral surface of right hind paw to induce periphery inflammatory pain. The flinches of rats were counted to observe their painful reaction. Flow cytometry was used to assay the ratio of apoptosis of hippocampal neurons. The immunohistochemistry was used to observe the expression of p53 protein in hippocampal subregions.

RESULTSCompared with control group, the apoptotic ratio of hippocampal neurons was significantly increased in rats with inflammatory pain, and formalin inflammatory pain induced upregulation of p53 protein expression in all hippocampal subregions. Both the apoptotic ratio and the p53 protein expression peaked on the third day after the formalin injection. The twice injection of formalin into the hind paws of rats resulted in an enhancement of painful reaction and increase in apoptotic ratio of hippocampal neurons compared with the rats of injection formalin once group.

CONCLUSIONFormalin inflammatory pain can induce the hippocampal neuronal apoptosis in rats with a certain time course. Neuronal apoptosis is relevant to the intensity of pain. The up-regulation of p53 protein expression may implicate in the induction of hippocampal neuronal apoptosis in rats with inflammatory pain.

Animals ; Apoptosis ; Formaldehyde ; Hippocampus ; pathology ; physiopathology ; Inflammation ; chemically induced ; physiopathology ; Male ; Neurons ; pathology ; Pain ; chemically induced ; physiopathology ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Tumor Suppressor Protein p53 ; metabolism

This study investigated the role of glycogen synthase kinase-3β (GSK-3β) in isoflurane-induced neuroinflammation and cognitive dysfunction in aged rats. The hippocampi were dissected from aged rats which had been intraperitoneally administered lithium chloride (LiCl, 100 mg/kg) and then exposed to 1.4% isoflurane for 6 h. The expression of GSK-3β was detected by Western blotting. The mRNA and protein expression levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 were measured by real-time PCR and enzyme-linked immunosorbent assay (ELISA), respectively. Morris water maze was employed to detect spatial memory ability of rats. The results revealed that the level of GSK-3β was upregulated after isofurane exposure. Real-time PCR analysis demonstrated that isoflurane anesthesia increased mRNA levels of TNF-α, IL-1β and IL-6, which was consistent with the ELISA results. However, these changes were reversed by prophylactic LiCl, a non-selective inhibitor of GSK-3β. Additionally, we discovered that LiCl alleviated isoflurane-induced cognitive impairment in aged rats. Furthermore, the role of GSK-3β in isoflurae-induced neuroinflammation and cognitive dysfunction was associated with acetylation of NF-κB p65 (Lys310). In conclusion, these results suggested that GSK-3β is associated with isoflurane-induced upregulation of proinflammatory cytokines and cognitive disorder in aged rats.
Animals ; Cognition Disorders ; chemically induced ; metabolism ; pathology ; Glycogen Synthase Kinase 3 ; metabolism ; Glycogen Synthase Kinase 3 beta ; Inflammation ; chemically induced ; metabolism ; pathology ; Isoflurane ; adverse effects ; Male ; Neurons ; drug effects ; metabolism ; pathology ; Rats ; Rats, Sprague-Dawley

Glucocorticoid-induced TNF receptor (GITR) was a new member of the TNF/nerve growth factor receptor (TNFR/ NGFR) family and induced in murine T cells by dexamathasone. Recombinant soluble GITR (sGITR) induced an inflammation in peritoneal membrane and changes in spleen after i.p. injection of 3 mg/kg in C57BL/6 mice. Spleen was enlarged and percentage of neutrophils and monocytes were increased. The area of red pulp in spleen was increased, while that of white pulp was decreased after GITR injection. The thickening of membrane and neutrophil infiltration was observed in peritoneal membrane with increased myeloperoxidase activity. At later time, neutrophil infiltration moved to inside the tissue with tissue damage. GITR ligand and GITR were expressed constitutively on the surface of spleen cells and cells from peritoneal fluid. In contrast, no significant change in the spleen and in peritoneal membrane was observed in mice treated with LPS. GITR may play a role in body's inflammatory processes.
Animals ; Carrier Proteins/metabolism ; Flow Cytometry ; Inflammation/*chemically induced/pathology ; Injections ; Male ; Mice ; Mice, Inbred C57BL ; Receptors, Nerve Growth Factor/*metabolism ; Receptors, Tumor Necrosis Factor/*metabolism ; Solubility ; Spleen/metabolism/pathology ; Support, Non-U.S. Gov't

Anti-cancer drug bleomycin (BLM) can cause acute lung injury (ALI) which often results in pulmonary fibrosis due to a failure of resolving acute inflammatory response. The aim of this study is to investigate whether toll-like receptor (TLR) 2 mediates BLM-induced ALI, inflammation and fibrosis. BLM-induced dendritic cells (DCs) maturation was analyzed by flow cytometry and cytokine secretion was detected by the ELISA method. The expression and activity of p38 and ERK MAPK were determined with Western blotting. The roles of TLR2 in ALI, inflammation and fibrosis were investigated in C57BL/6 mice administered intratracheally with BLM. The results demonstrated that BLM-administered mice had higher expression of TLR2 (P<0.001) and its signaling molecules. Blocking TLR2 significantly inhibited the maturation of DCs and reversed BLM-stimulated secretion of cytokines in DCs, such as IL-6 (P<0.001), IL-17 (P<0.05) and IL-23 (P<0.05). TLR2 inhibition attenuated BLM-induced increase of inflammatory cells in bronchoalveolar lavage fluid (BALF), and reversed the immunosuppressive microenvironment by enhancing TH1 response (P<0.05) and inhibiting TH2 (P<0.001), Treg (P<0.01) and TH17 (P<0.01) responses. Importantly, blocking TLR2 in vivo significantly protected BLM-administered mice from pulmonary injury, inflammation and fibrosis and subsequently increased BLM-induced animal survival (from 50% to 92%). Therefore, TLR2 is a novel potential target for ALI and pulmonary fibrosis.
Acute Lung Injury ; chemically induced ; metabolism ; pathology ; Animals ; Bleomycin ; toxicity ; Bronchoalveolar Lavage Fluid ; Cells, Cultured ; Cytokines ; secretion ; Dendritic Cells ; cytology ; metabolism ; Inflammation ; chemically induced ; metabolism ; pathology ; Interleukin-17 ; secretion ; Interleukin-23 ; secretion ; Interleukin-6 ; secretion ; Lung ; metabolism ; MAP Kinase Signaling System ; Male ; Mice ; Mice, Inbred C57BL ; Pulmonary Fibrosis ; chemically induced ; metabolism ; pathology ; T-Lymphocytes, Regulatory ; drug effects ; Th1 Cells ; drug effects ; Th2 Cells ; drug effects ; Toll-Like Receptor 2 ; metabolism ; physiology

Hypercoagulable state and thrombosis are major lethal causes of ulcerate colitis (UC). The aim of the present study is to explore the change and role of protein C (PC) system in UC thrombosis. 4% dextran sulfate sodium (DSS) was used to induce the UC model, and the body weight, the length of colon, and the weight of spleen were measured after intake of DSS as drinking water for 1 week. The macroscore and microscore were examined. The quantity of macrophage in colon smooth muscle was observed by immunofluorescence, and TNF-α and IL-6 levels in plasma were evaluated by ELISA. Intravital microscopy was applied to observe colonic mucosal microvascular circulation, activities of PC and protein S (PS) were determined by immunoturbidimetry, endothelial cell protein C receptor (EPCR) and thrombomodulin (TM) expressions were detected by immunohistochemistry. In vitro, TNF-α and IL-6 levels were tested in supernatant of macrophage separated from colonic tissue. After stimulation of mouse colonic mucosa microvascular endothelial cells by TNF-α and IL-6 respectively, the activities of PC, PS, activated protein C (APC) were evaluated, and the expressions of EPCR and TM were detected by Western blotting. The results revealed that compared with control, the DSS mouse showed weight loss (P < 0.05), a shortened colon (P < 0.05), and swelled spleen (P < 0.05), accompanied by higher histological score (P < 0.05), as well as infiltration of macrophages, elevated TNF-α and IL-6 levels in plasma (P < 0.01). The intravital microscopy results revealed that compared with control, DSS mice showed significantly enhanced adhesion of leukocytes and colonic mucosal microvascular endothelial cells (P < 0.01), meanwhile, decreased activity of PC and PS in plasma (P < 0.01 or P < 0.05), and down-regulated expression of EPCR (P < 0.01). The degree of inflammation was negatively correlated with the PC activity. In vitro, TNF-α and IL-6 levels were increased in the supernatant of macrophages from DSS mice colonic tissue (P < 0.05), and after incubation of TNF-α or IL-6 with colonic mucosal microvascular endothelial cells, the APC activity was decreased (P < 0.05 or P < 0.01), and expression of EPCR was down regulated (P < 0.05). These results suggest that PC system is inhibited in UC mouse. Presumably, the mechanism may be due to the secretion of cytokines from macrophages and subsequential influence on the function of endothelia cells. Furthermore, enhancement of PC system activity may serve as a new strategy for the treatment of UC.
Animals ; Blood Coagulation Factors ; metabolism ; Colitis, Ulcerative ; chemically induced ; physiopathology ; Dextran Sulfate ; Immunohistochemistry ; Inflammation ; Interleukin-6 ; blood ; Intestinal Mucosa ; pathology ; Macrophages ; cytology ; Mice ; Protein C ; metabolism ; Receptors, Cell Surface ; metabolism ; Spleen ; pathology ; Tumor Necrosis Factor-alpha ; blood

AIMTo investigate the effects of low concentration carbon monoxide (CO) inhalation or intraperitoneal infusion on lipopolysaccharide (LPS) induced rat small intestine injury and to detect the roles of p38 mitogen-activated protein kinase (MAPK) pathway during CO administration.

METHODSSD rats with small intestine injury induced by 5 mg/kg LPS intravenous injection were challenged by room air, 2.5 x 10(-4)(V/V) CO inhalation or intraperitoneal infusion for 1 h, 3 h and 6 h differently. Then all animals were sacrificed, and the ileum tissues were homogenized for determination the levels of platelet activator factor(PAF) and intercellular adhesion molecule-1 (ICAM-1) with enzyme-lined immunosorbent assay, the pathology with light microscope, and the phosphorylated p38 MAPK expression with Western blot.

RESULTSCompared with either control, CO inhalation or intraperitoneal infusion group at the same time point, the levels of PAF, ICAM-1 and the phosphorylated p38 MAPK of LPS group were increased (all P < 0.01), but there were no statistics differences at the different time point of this group. PAF and ICAM-1 in both LPS injection + CO inhalation group and LPS injection + CO intraperitoneal infusion group were significantly lower than the corresponding value in LPS injection group at the same time point (all P < 0.05), while the expression of phosphorylated p38 MAPK was further up-regulated than that of LPS injection group (P < 0.05). However, there were no significant differences in these parameters between LPS injection+ CO inhalation group and LPS injection+ CO intraperitoneal infusion group.

CONCLUSIONLow concentration CO inhalation and intraperitoneal infusion exerts the similar protection against LPS induced rat small intestine injury via down-regulating PAF and ICAM-1 expression. This may involve the p38 MAPK pathway.

Animals ; Carbon Monoxide ; pharmacology ; Down-Regulation ; Inflammation ; chemically induced ; Intercellular Adhesion Molecule-1 ; metabolism ; Intestine, Small ; metabolism ; pathology ; Lipopolysaccharides ; antagonists & inhibitors ; toxicity ; Male ; Phosphorylation ; Platelet Activating Factor ; metabolism ; Rats ; Rats, Sprague-Dawley ; p38 Mitogen-Activated Protein Kinases ; metabolism

High-density lipoprotein (HDL), an abundant plasma lipoprotein, has been thought to be anti-inflammatory in both health and infectious diseases. It binds lipopolysaccharide (LPS) and neutralizes its bioactivity. The present study aimed to investigate the potential role of HDL, which was separated from human plasma, in LPS-induced acute lung injury in mice. Kunming mice (18-22 g) were treated with either HDL (70 mg/kg body weight, via tail vein) or saline 30 min after LPS administration (10 mg/kg body weight, intraperitoneally) and were decapitated 6 h after LPS challenge. The arterial blood was collected and analyzed for blood gas variables (PaO(2), pH, and PaCO(2)). The bronchoalveolar lavage fluid (BALF) samples were analyzed for total protein concentration, lactate dehydrogenase (LDH) activity, and white blood cell (WBC) count. The lung samples were taken for histopathological evaluation and for determination of lung wet-to-dry weight ratio (W/D), malondialdehyde (MDA) content, myeloperoxidase (MPO) activity and tumor necrosis factor α (TNF-α) content. Arterial blood gas analysis showed that after LPS challenge, HDL-treated mice exhibited a higher PaO(2), and pH, but a lower PaCO(2) than HDL-untreated ones (P<0.01). LPS-induced increases in total protein concentration, WBC number and LDH activity in BALF were significantly attenuated in HDL-treated mice (P<0.01). HDL treatment also resulted in a significant protection of lung tissues against LPS-induced acute lung injury via decreasing W/D ratio, MPO activity, MDA content, and the content of the pro-inflammatory cytokine TNF-α (P<0.05, P<0.01). Histological examination revealed that HDL treatment resulted in significantly lower scores of acute lung injury induced by LPS, with reduced hemorrhage, intra-alveolar edema and neutrophilic infiltration (P<0.01). It is suggested that HDL plays a protective role in attenuating LPS-induced acute lung injury in mice.
Acute Lung Injury ; chemically induced ; therapy ; Animals ; Bronchoalveolar Lavage Fluid ; chemistry ; Inflammation ; metabolism ; Leukocyte Count ; Lipopolysaccharides ; adverse effects ; Lipoproteins, HDL ; pharmacology ; Lung ; pathology ; Malondialdehyde ; metabolism ; Mice ; Peroxidase ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo evaluate the role of thrombin-activated microglia in the neurodegeneration of nigral dopaminergic neurons in the rat substantia nigra (SN) in vivo.

METHODSAfter stereotaxic thrombin injection into unilateral SN of rats, immunostaining, reverse transcription polymerase chain reaction (RT-PCR) and biochemical methods were used to observe tyrosine hydroxylase (TH) immunoreactive positive cells, microglia activation, nitric oxide (NO) amount and inducible nitric-oxide synthase (iNOS) expression.

RESULTS(1) Selective damage to dopaminergic neurons was produced after thrombin injection, which was evidenced by loss of TH immunostaining in time-dependent manner; (2) Strong microglial activation was observed in the SN; (3) RT-PCR demonstrated the early and transient expression of neurotoxic factors iNOS mRNA in the SN. Immunofluorescence results found that thrombin induced expression of iNOS in microglia. The NO production in the thrombin-injected rats was significantly higher than that of controls (P < 0.05).

CONCLUSIONThrombin intranigral injection can injure the dopaminergic neurons in the SN. Thrombin-induced microglia activation precedes dopaminergic neuron degeneration, which suggest that activation of microglia and release of NO may play important roles in dopaminergic neuronal death in the SN.

Animals ; Disease Progression ; Dopamine ; biosynthesis ; Encephalitis ; chemically induced ; metabolism ; physiopathology ; Female ; Gliosis ; chemically induced ; metabolism ; physiopathology ; Immunohistochemistry ; Inflammation Mediators ; toxicity ; Injections ; Microglia ; drug effects ; metabolism ; Nerve Degeneration ; chemically induced ; metabolism ; physiopathology ; Neurons ; drug effects ; metabolism ; pathology ; Nitric Oxide ; biosynthesis ; Nitric Oxide Synthase Type II ; drug effects ; metabolism ; Oxidative Stress ; drug effects ; physiology ; Parkinsonian Disorders ; chemically induced ; metabolism ; physiopathology ; RNA, Messenger ; drug effects ; metabolism ; Rats ; Rats, Sprague-Dawley ; Reverse Transcriptase Polymerase Chain Reaction ; Substantia Nigra ; drug effects ; metabolism ; physiopathology ; Thrombin ; toxicity ; Time Factors ; Tyrosine 3-Monooxygenase ; drug effects ; genetics ; metabolism ; Up-Regulation ; drug effects ; physiology

OBJECTIVETo investigate the effect of prostaglandin D2 receptor antagonists on the airway inflammation in rats with asthma.

METHODSForty male SD rats were randomly divided into four groups: Group A (normal control), Group B (asthma group), Group C (CRTH2 antagonist BAYu3405 treatment group), Group D (DP1 antagonist BWA868C treatment group). Asthma was induced by ovalbumin (OVA) challenge. The rats in each group were sacrificed 24 h after the last challenge of OVA.DP1/CRTH2 receptors on eosinophils (EOS) were measured by radiological binding assay (RBA). The left lungs were used for histological examinations and bronchoalveolar lavage fluid (BALF) was collected from the right lungs. The total cell numbers, EOS absolute count and differential cell counts in BALF were performed. Serum concentrations of IL-4, 5 and IFN-gamma were measured by ELISA.

RESULTSRats in BAYu3405 treatment group showed profoundly decreased infiltrates of EOS and lymphocytes in the wall of bronchus when compared with those of asthma group and BWA868C treatment group. Serum concentrations of IFN-gamma in rats of BAYu3405 treatment group increased, but IL-4 and IL-5 decreased significantly when compared with those in rats of asthma group and BWA868C treatment group (P<0.01), and BALF EOS count was decreased significantly (P<0.01). Peripheral blood EOS count was higher than that in rats of normal control group, but was not significantly different from that in rats of asthma group and BWA868C treatment group. The combining capacity of CRTH2 and DP total combining capacity on EOS in asthma group, BAYu3405 treatment group and BWA868C treatment group were significantly higher than those in Group A (P<0.01). There was no significant difference in DP1 among all the groups (P>0.05).

CONCLUSIONCRTH2, but not DP1 antagonist can effectively ameliorate airway inflammation in rats with asthma.

Animals ; Asthma ; chemically induced ; drug therapy ; pathology ; Bronchi ; immunology ; pathology ; Carbazoles ; pharmacology ; therapeutic use ; Inflammation ; drug therapy ; Male ; Ovalbumin ; Prostaglandin D2 ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Receptors, Immunologic ; antagonists & inhibitors ; Receptors, Prostaglandin ; antagonists & inhibitors ; Sulfonamides ; pharmacology ; therapeutic use

The aim of the present study is to investigate the effects of Vam3 which is one of the dihydroxystilbene compounds on expressions of ICAM-1 in the lungs of OVA-induced asthmatic mice and the mechanisms of anti-airway inflammation. Balb/c mice were challenged with OVA inhalation. Lung tissues were stained with Mayer's hematoxylin and eosin for histopathologic examination. The expression of ICAM-1 in the lungs of mice was analyzed by Western blotting and immunohistochemistry method. The NF-kappaB activities were detected by NF-kappaB-luc reporter genetic transient transfection method. The activities of MMP-9 induced by LPS, TNF-alpha and PMA in THP-1 cells were determined by gelatin zymography method. The results showed that Vam3 could inhibit the expression of ICAM-1 in the OVA-induced mouse model. In addition, Vam3 could significantly suppress the activities of NF-kappaB in A549 cells and MMP-9 in THP-1 cells induced by LPS, TNF-alpha and PMA. These results suggested that Vam3 could alleviate the asthmatic inflammation by decreasing ICAM-1 expression in asthmatic mice, down regulating NF-kappaB and MMP-9 activities. Compound Vam3 showed inhibitory effects on inflammatory signal pathways involved in asthma.
Animals ; Anti-Asthmatic Agents ; pharmacology ; Anti-Inflammatory Agents ; pharmacology ; Asthma ; chemically induced ; metabolism ; Benzofurans ; pharmacology ; Cell Line, Tumor ; Humans ; Inflammation ; metabolism ; Intercellular Adhesion Molecule-1 ; metabolism ; Leukemia, Myeloid ; metabolism ; pathology ; Lung ; metabolism ; pathology ; Lung Neoplasms ; metabolism ; pathology ; Male ; Matrix Metalloproteinase 9 ; metabolism ; Mice ; Mice, Inbred BALB C ; NF-kappa B ; metabolism ; Ovalbumin ; Stilbenes ; pharmacology