The complement cascade is a central component of innate immunity which plays a critical role in brain inflammation. Complement C3a receptor (C3aR) is a key mediator of post-ischemic cerebral injury, and pharmacological antagonism of the C3a receptor is neuroprotective in stroke. Cerebral ischemia injures brain endothelial cells, causing blood brain barrier (BBB) disruption which further exacerbates ischemic neuronal injury. In this study, we used an in vitro model of ischemia (oxygen glucose deprivation; OGD) to investigate the protective effect of a C3aR antagonist (C3aRA, SB290157) on brain endothelial cells (bEnd.3). Following 24 hours of reperfusion, OGD-induced cell death was assessed by TUNEL and Caspase-3 staining. Western blot and immunocytochemistry were utilized to demonstrate that OGD upregulates inflammatory, oxidative stress and antioxidant markers (ICAM-1, Cox-2, Nox-2 and MnSOD) in endothelial cells and that C3aRA treatment significantly attenuate these markers. We also found that C3aRA administration restored the expression level of the tight junction protein occludin in endothelial cells following OGD. Interestingly, OGD/reperfusion injury increased the phosphorylation of ERK1/2 and C3aR inhibition significantly reduced the activation of ERK suggesting that endothelial C3aR may act via ERK signaling. Furthermore, exogenous C3a administration stimulates these same inflammatory mechanisms both with and without OGD, and C3aRA suppresses these C3a-mediated responses, supporting an antagonist role for C3aRA. Based on these results, we conclude that C3aRA administration attenuates inflammation, oxidative stress, ERK activation, and protects brain endothelial cells following experimental brain ischemia.
Blood-Brain Barrier ; Blotting, Western ; Brain Ischemia ; Brain ; Caspase 3 ; Cell Death ; Complement C3a ; Complement System Proteins ; Encephalitis ; Endothelial Cells ; Glucose ; Immunity, Innate ; Immunohistochemistry ; In Situ Nick-End Labeling ; In Vitro Techniques ; Inflammation ; Ischemia ; Neurons ; Occludin ; Oxidative Stress ; Phosphorylation ; Reperfusion ; Stroke ; Tight Junctions

BACKGROUND: We aimed to estimate whether elevated levels of complement C3a and C5a in amniotic fluid (AF) are independently associated with increased risks of intra-amniotic infection and/or inflammation (IAI) and spontaneous preterm delivery (SPTD) in women with cervical insufficiency or a short cervix (≤ 25 mm). METHODS: We conducted a retrospective cohort study of 96 consecutive women with cervical insufficiency (n = 62) or a short cervix (n = 34) at 17 to 27 weeks, and who underwent an amniocentesis. AF was cultured and analyzed for C3a and C5a by enzyme-linked immunosorbent assay kits. The primary outcome measures were IAI (defined as a positive AF culture and/or an elevated AF interleukin-6 level [≥ 7.6 ng/mL]) and SPTD at < 32 weeks. RESULTS: In multivariable analysis, AF level of C3a was the only variable significantly associated with IAI, whereas C5a level in AF and serum C-reactive protein level were not associated with IAI. Using SPTD at < 32 weeks as the outcome variable in logistic regression, elevated AF levels of C3a were associated with increased risk of SPTD at < 32 weeks after adjusting for other baseline confounders, whereas elevated AF levels of C5a were not. CONCLUSION: In women with cervical insufficiency or a short cervix, elevated AF level of C3a, but not C5a, is independently associated with increased risks of IAI and SPTD at < 32 weeks. These findings suggest that subclinical IAI or SPTD in the context of cervical insufficiency is related to activation of complement system in AF.
Amniocentesis ; Amniotic Fluid* ; C-Reactive Protein ; Cervix Uteri* ; Cohort Studies ; Complement C3a* ; Complement System Proteins* ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Inflammation* ; Interleukin-6 ; Logistic Models ; Outcome Assessment (Health Care) ; Retrospective Studies

OBJECTIVETo investigate the effect of Liuwei Wuling tablets on the cytoplasmic translocation and release of high-mobility group box-1 (HMGB1) in hepatocytes in mice with acute live injury induced by D-galactosamine (D-GalN) and lipopolysaccharide (LPS).

METHODSA Balb/c mouse model of acute liver injury was established by intraperitoneal injection of D-GalN (400 mg/kg) and LPS (5 ug/kg). A total of 24 healthy mice were randomly and equally divided into acute liver injury control group and Liuwei Wuling tablet treatment group. The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured in both groups at each time point within one week. Liver tissues were collected at 36 hours to perform pathological examination. The serum levels of HMGB1, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), complement 3a (C3a), and complement 5a (C5a) were measured. Immunohistochemistry was used to determine the expression and cytoplasmic translocation of HMGB1 in hepatocytes.

RESULTSAt 6, 12, and 24 hours, the Liuwei Wuling tablet treatment group had significantly lower serum levels of ALT than the control group (225.33±181.64 U/L vs 471.17±174.72 U/L, t = 3.38, P < 0.01; 1509.53±182.51 U/L vs 7149.52±734.25 U/L, t = 25.82, P < 0.01; 162.89±86.51 U/L vs 1318.16±557.71 U/L, t = 7.09, P < 0.01), as well as significantly lower serum levels of AST than the control group (179.22±94.57 U/L vs 561.91±209.6 U/L, t = 5.76, P < 0.01; 590.92±190.92 U/L vs 2266.48±705.64 U/L, t = 7.94, P < 0.01; 231.24±87.7 U/L vs 444.32±117.01 U/L, t = 5.05, P < 0.01). The treatment group had significantly lower levels of HMGB1 than the control group at 6 and 12 hours (54.21±11.89 ng/ml vs 72.07±13.65 ng/ml, t = 3.41, P < 0.01; 49.23±5.97 ng/ml vs 68.71±13.07 ng/ml, t = 4.70, P < 0.01). The treatment group had significantly lower levels of TNF-α, IL-1β, and IL-6 than the control group at 12 hours (163.62±9.12 pg/ml vs 237.09±51.47 pg/ml, t = 4.86, P < 0.01; 15.66±13.13 pg/ml vs 37.43±18.68 pg/ml, t = 3.30, P < 0.01; 7.10±3.06 pg/ml vs 21.42±8.23 pg/ml, t = 5.65, P < 0.01). The treatment group had significantly lower levels of C3a and C5a than the control group at 12 hours (2.52±1.27 pg/ml vs 9.83±2.96 ng/ml, t = 7.86, P < 0.01; 2.16±1.03 ng/ml vs 7.23±1.55 ng/ml, t = 9.67, P < 0.01). Compared with the control group, the treatment group had significantly reduced liver inflammation and necrosis, and a significantly lower cytoplasmic translocation rate of HMGB1 in hepatocytes (38.76%±7.37% vs 8.15%±2.11%, P < 0.01).

CONCLUSIONLiuwei Wuling tablets can reduce the cytoplasmic translocation of HMGB1 in hepatocytes and relieve liver inflammation in mice with acute liver injury.

Alanine Transaminase ; blood ; Animals ; Aspartate Aminotransferases ; blood ; Complement C3a ; analysis ; Complement C5a ; analysis ; Cytoplasm ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Galactosamine ; HMGB1 Protein ; metabolism ; Hepatocytes ; drug effects ; Interleukin-1beta ; blood ; Interleukin-6 ; blood ; Lipopolysaccharides ; Liver Failure, Acute ; drug therapy ; Mice ; Mice, Inbred BALB C ; Protein Transport ; Tablets ; Tumor Necrosis Factor-alpha ; blood

OBJECTIVETo investigate the clinical significance of anaphylatoxin C3a in induced sputum in patients with asthma.

METHODSThe patients with acute exacerbation of asthma treated at our department between September, 2006 and February, 2007 were included in the study. The demographic data, medical history, levels of lung function and C3a levels in induced sputum were assessed.

RESULTSA total of 33 patients were included in the study. The level of C3a in induced sputum was significantly higher in patients with acute exacerbation of asthma (2.24 ng/ml, range 1.68-5.58 ng/ml) than that in patients with asthma remission (0.7 ng/ml, range 0.24-2.31 ng/ml, P<0.05). Sputum C3a levels in the remission patients were significantly higher than those in the healthy controls (0.12 ng/ml, range 0.07-0.39 ng/ml, P<0.05). The levels of C3a in patients with severe exacerbation (4.69 ng/ml, range 2.69-6.59 ng/ml) were significantly higher than those in patients with mild exacerbation (0.25 ng/ml, range 0.09-0.40 ng/ml) and moderate exacerbation (2.21 ng/ml, range 1.16-3.41 ng/ml) (P<0.01), and were significantly higher in patients with moderate exacerbation than in those in mild exacerbation (P<0.01). The level of C3a in induced sputum was positively correlated with the number of total cell count (r=0.718, P<0.05), eosinophils (r=0.495, P<0.05) and macrophages (r=0.600, P<0.05) in patients with acute exacerbation of asthma.

CONCLUSIONInduced sputum C3a level can serve as an important clinical biomarker for clinical asthma management.

Asthma ; physiopathology ; Biomarkers ; chemistry ; Case-Control Studies ; Complement C3a ; chemistry ; Eosinophils ; Humans ; Leukocyte Count ; Macrophages ; Sputum ; chemistry

OBJECTIVETo determine the levels of complement components C3a and C5a in the kidneys of trichloroethylene (TCE)-sensitized BALB/c mice, and to investigate the role of complement components in TCE-induced renal injury among BALB/c mice.

METHODSSixty-two female BALB/c mice were randomly divided into blank control group, vehicle control group, and TCE sensitization group. The mice in TCE sensitization group were sensitized by one intracutaneous injection and one abdominal smear of TCE. At 24 h, 48 h, 72 h, and 7 d after the second sensitization, mice were sacrificed, and the blood and kidneys were collected. An automatic biochemical analyzer was used in the determination of serum blood urea nitrogen (BUN) and creatinine (Cr). The levels of C3a and C5a in the kidneys were determined by immunohistochemistry.

RESULTSThe sensitization rate of TCE sensitization group was 42.0%. Kidney coefficient and serum levels of BUN and Cr were significantly increased in the TCE sensitization group as compared with the vehicle control group at 48 h and 72 h after sensitization (P < 0.05). The kidney coefficients of the TCE sensitization group at 48 h and 72 h were significantly higher than those of the control groups (P < 0.05). In comparison with the vehicle control group, however, no significant change was found in kidney coefficient, serum BUN, or serum Cr at 7 d after TCE sensitization (P > 0.05). Levels of C3a and C5a at 48 h (3.80±0.84 and 4.00±1.00, respectively) and 72 h (4.40 ± 1.14 and 4.40 ± 1.14, respectively) after sensitization were all significantly higher than those of the vehicle control group (P < 0.05), but no significant difference was found in level of C3a (1.80±0.45) or C5a (2.00 ± 0.71) at 7 d (P > 0.05).

CONCLUSIONTCE sensitization can induce renal injury in mice. Levels of complement components C3a and C5a are elevated in the kidneys of sensitized mice, indicating that C3a and C5a may be involved in the renal injury induced by TCE sensitization.

Animals ; Blood Urea Nitrogen ; Complement C3a ; metabolism ; Complement C5a ; metabolism ; Creatinine ; blood ; Female ; Kidney ; metabolism ; pathology ; Mice ; Mice, Inbred BALB C ; Trichloroethylene ; toxicity

OBJECTIVETo study whether alisol B could inhibit complement 3a (C3a) induced renal tubular epithelial-mesenchymal transition (EMT).

METHODSThe in vitro cultured human renal tubular epithelial HK-2 cells were intervened with 5 ng/mL transforming growth factor-beta (TGF-beta), 0.1 micromol C3a, and 0.1 micromol C3a + 10 micromol alisol B, respectively. The mRNA and protein expressions of alpha-SMA, E-cadherin, and C3 were detected using RT-PCR, Western blot, and immunofluorescence, respectively.

RESULTSThe mRNA and protein expressions of C3 in HK-2 cells were up-regulated after intervention of C3a (P < 0.01), the mRNA and protein expressions of alpha-SMA in HK-2 cells were obviously enhanced (P < 0.01), the mRNA and protein expressions of E-cadherin obviously decreased (P < 0.01). When compared with the group intervened by exogenous C3a, after intervention of alisol B, the mRNA and protein expressions of alpha-SMA in HK-2 cells were obviously reduced (P < 0.01), the mRNA and protein expressions of E-cadherin obviously increased (P < 0.05).

CONCLUSIONSExogenous C3a could induce renal tubular EMT. Alisol B was capable of suppressing C3a induced EMT.

Actins ; metabolism ; Cadherins ; metabolism ; Cell Differentiation ; drug effects ; Cell Line ; Cholestenones ; pharmacology ; Complement C3a ; metabolism ; Epithelial Cells ; drug effects ; metabolism ; Epithelial-Mesenchymal Transition ; drug effects ; Humans ; Kidney Tubules ; cytology ; metabolism

BACKGROUNDTubulointerstitial renal fibrosis is the common end point of progressive kidney diseases, and tubular epithelial-myofibroblast transdifferentiation (TEMT) plays a key role in the progress of tubulointerstitial renal fibrosis. Anaphylatoxin C3a and C5a are identified as novel profibrotic factors in renal disease and as potential new therapeutic targets. The aim of this study was to investigate whether C3a, C5a can regulate TEMT by transforming growth factor-β1 (TGF-β)/connective tissue growth factor (CTGF) signaling pathway and the effects of C3a and C5a receptor antagonists (C3aRA and C5aRA) on C3a- and C5a-induced TEMT.

METHODSHK-2 cells were divided into C3a and C5a groups which were subdivided into four subgroups: control group, 10 ng/ml TGF-β1 group, 50 nmol/L C3a group, 50 nmol/L C3a plus 1 µmol/L C3aRA group; control group, 10 ng/ml TGF-β1 group, 50 nmol/L C5a group, 50 nmol/L C5a plus 2.5 µmol/L C5aRA group. TGF-β1 receptor antagonist (TGF-β1RA) 10 µg/ml was used to investigate the mechanism of C3a- and C5a-induced TEMT. Electron microscopy was used to observe the morphological changes. Immunocytochemistry staining, real-time PCR and Western blotting were used to detect the expressions of a smooth muscle actin (α-SMA), E-cadherin, Col-I, C3a receptor (C3aR), C5aR, CTGF and TGF-β1.

RESULTSHK-2 cells cultured with C3a and C5a for 72 hours exhibited strong staining of α-SMA, lost the positive staining of E-cadherin, and showed a slightly spindle-like shape and loss of microvilli on the cell surface. The expressions of α-SMA, E-cadherin, Col-I, C3aR, C5aR, TGF-β1 and CTGF in C3a- and C5a-treated groups were higher than normal control group (P < 0.05). C3aRA and C5aRA inhibited the expressions of α-SMA, Col-I, C3aR, C5aR, and up-regulated the expression of E-cadherin (P < 0.05). TGF-β1 and CTGF mRNA expressions induced by C3a and C5a were partly blocked by TGF-β1RA (P < 0.05).

CONCLUSIONC3a and C5a can induce TEMT via the up-regulations of C3aR and C5aR mRNA and the activation of TGF-β1/CTGF signaling pathway in vitro.

Blotting, Western ; Cadherins ; genetics ; Cell Line ; Cell Transdifferentiation ; drug effects ; Complement C3a ; pharmacology ; Complement C5a ; pharmacology ; Epithelial Cells ; cytology ; drug effects ; ultrastructure ; Humans ; Immunohistochemistry ; Microscopy, Electron, Scanning ; Myofibroblasts ; cytology ; drug effects ; ultrastructure ; Real-Time Polymerase Chain Reaction

Perilipin and adipophilin, two significant lipid droplet (LD)-specific proteins, participate in storing fat or ectopic lipid deposition and fat mobilization in many types of mammalian cells. Acylation stimulating protein (ASP) is a novel adipocyte-derived hormone known for a major determinant for triglyceride synthesis (TGS) and lipid metabolism. The present study was aimed to investigate: (1) whether ASP, rather than insulin, is a powerful potentiator which could physiologically and directly influence TGS during 3T3-L1 preadipocyte differentiation; (2) whether ASP exposure at indicated time points during 3T3-L1 preadipocyte differentiation could influence the gene/protein expression of adipophilin and perilipin. 3T3-L1 preadipocytes were differentiated by traditional hormone cocktail and divided into control, ASP and insulin groups according to the treatment of ASP (1 mmol/L) or insulin (100 nmol/L). ASP-stimulated and insulin-stimulated TGS rate at indicated time points (0 d, 3 d, 6 d, 9 d) were assayed by measuring the incorporation of [(3)H]-oleic acid into TG, and the corresponding glucose transport was assayed by [(3)H]-2-DG uptake. The effects of ASP or insulin on gene/protein expression of adipophilin and perilipin at indicated time points were evaluated by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. The results obtained were as follows: (1) on the 3rd and 6th day of differentiation, ASP dramatically enhanced TGS rate compared with control group (P<0.05, P<0.01); There was no significant difference in TGS rate between insulin group and control group; (2) on the 6th and 9th day of differentiation, both ASP and insulin promoted glucose uptake (P<0.05, P<0.01), and the promoting effect in ASP group was greater than that in insulin group; (3) ASP elevated adipophilin gene and protein expression at the very early stage of differentiation (P<0.05, P<0.001) and had no significant effect from the 4th day of differentiation. Perilipin gene and protein expression increased throughout preadipocyte differentiation and its expression was up-regulated following ASP stimulation from the 3rd day of differentiation (P<0.05, P<0.001) to the end of differentiation (P<0.05); (4) Insulin did not affect gene and protein variation pattern of adipophilin and perilipin. Taken together, this study provides evidence that ASP-evoked changes in gene and protein expression of adipophilin and perilipin correlate with ASP-stimulated TGS acceleration, and adipophilin and perilipin are involved in the molecular mechanism of ASP-induced adipogenesis and LD formation.
3T3-L1 Cells ; Adipocytes ; cytology ; Animals ; Carrier Proteins ; metabolism ; Cell Differentiation ; Complement C3a ; pharmacology ; Gene Expression ; Insulin ; pharmacology ; Membrane Proteins ; metabolism ; Mice ; Perilipin-1 ; Perilipin-2 ; Phosphoproteins ; metabolism

OBJECTIVETo evaluate the hemocompatibility of glutaraldehyde (GA)-tanned bovine pericardium additionally treated by sodium bisulfite (SOB) solution.

METHODSThe hemocompatibility of GA-tanned bovine pericardium treated by SOB solution is evaluated by using dynamic clotting time test, blood platelet adhension test, D-dimeride determination, and complement activation test. The GA-tanned bovine pericardium was used as control.

RESULTSThe curve of absorbance-clotting time of two kinds of bovine pericardium was similar in dynamic clotting time test. There was no significant difference between SOB-treated and control groups in blood platelet adhension test. The D-dimeride contents of all bioprostheses were at normal level, and the D-dimeride content of GA-tanned bovine pericardium treated by SOB solution was significantly lower than that of control group (P < 0.05). In complement activation test, the level of complement C3a in SOB-treated group was significantly lower than that in control group (P < 0.05).

CONCLUSIONGA-tanned bovine pericardium treated by SOB solution meets the demands of cardiac interstitial implanted materials in hemocompatibility.

Animals ; Biocompatible Materials ; Bioprosthesis ; Blood Coagulation ; Cattle ; Complement C3a ; analysis ; Fibrin Fibrinogen Degradation Products ; metabolism ; Glutaral ; pharmacology ; Materials Testing ; Pericardium ; drug effects ; metabolism ; Platelet Adhesiveness ; Sulfites ; pharmacology

OBJECTIVETo investigate the role of sulfated tyrosine in regulating the activity of tyrosylprotein sulfotransferases (TPST) 1 and TPST2.

METHODSConstructs of TPST 1 and TPST2 were amplified by polymerase chain reaction (PCR), then fused into immunoglobulin G1 Fc region. All the variants in which sulfated tyrosines were mutated to phenylalanine were made by the PCR-based Quick Change method and confirmed by sequencing the entire reading frame. Small hairpin RNA (shRNA) constructs-targeting nucleotides 259-275 of TPST1 and nucleotides 73-94 of TPST2 were generated and subcloned into pBluescript. Human embryonic kidney (HEK) 293T cells were transfected with these plasmids. One day later, cells were split: one part was labeled with 35S-cysteine and methionine or 35S-Na2SO3 overnight, the second part was used for 125I labeled binding experiment, and the third part was retained for binding and flow cytometry.

RESULTSTyrosines at position 326 of TPST1 and position 325 of TPST2 were sulfated posttranslationally. Tyrosine sulfation of TPSTs was effectively inhibited by sulfation inhibitors, including specific shRNAs and non-specific NaCIO3. shRNAs reduced the sulfation of C3a receptor and C5a receptor, and partially blocked the binding of these two receptors to their respective ligands.

CONCLUSIONSThe activities of TPSTs were regulated by tyrosine sulfation. Inhibition of sulfotyrosine decreases the binding ability of C3a receptor and C5a receptor to their respective ligands.

Cell Line ; Complement C3a ; metabolism ; Complement C5a ; metabolism ; Humans ; Protein Binding ; Protein Processing, Post-Translational ; Receptor, Anaphylatoxin C5a ; metabolism ; Receptors, Complement ; metabolism ; Sulfotransferases ; genetics ; metabolism ; Transfection ; Tyrosine ; analogs & derivatives ; metabolism