[show abstract][hide abstract] ABSTRACT: Antiflammin-1 (AF-1), a derivative of uteroglobin (UG), is a synthetic nonapeptide with diverse biological functions. In the present study, we investigated whether AF-1 has a protective effect against bleomycin-induced pulmonary fibrosis.
C57BL/6 mice were injected with bleomycin intratracheally to create an animal model of bleomycin-induced pulmonary fibrosis. On Day 7 and Day 28, we examined the anti-inflammatory effect and antifibrotic effect, respectively, of AF-1 on the bleomycin-treated mice. The effects of AF-1 on the transforming growth factor-beta 1 (TGF-beta1)-induced proliferation of murine lung fibroblasts (NIH3T3) were examined by a bromodeoxycytidine (BrdU) incorporation assay and cell cycle analysis.
Severe lung inflammation and fibrosis were observed in the bleomycin-treated mice on Day 7 and Day 28, respectively. Administration of AF-1 significantly reduced the number of neutrophils in the bronchoalveolar lavage fluid (BALF) and the levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1beta) in the lung homogenates on Day 7. Histological examination revealed that AF-1 markedly reduced the number of infiltrating cells on Day 7 and attenuated the collagen deposition and destruction of lung architecture on Day 28. The hydroxyproline (HYP) content was significantly decreased in the AF-1-treated mice. In vitro, AF-1 inhibited the TGF-beta1-induced proliferation of NIH3T3 cells, which was mediated by the UG receptor.
AF-1 has anti-inflammatory and antifibrotic actions in bleomycin-induced lung injury. We propose that the antifibrotic effect of AF-1 might be related to its suppression of fibroblast growth in bleomycin-treated lungs and that AF-1 has potential as a new therapeutic tool for pulmonary fibrosis.
Respiratory research 10/2013; 14(1):101. · 3.64 Impact Factor
[show abstract][hide abstract] ABSTRACT: The present study investigated the effect of antiflammin-1 (AF-1) on LPS-induced IL-10 secretion from RAW264.7 cells through uteroglobin-binding protein (UGBP). Cultured RAW264.7 cells, a murine monocyte-macrophage cell line, were divided as following: control group, LPS group (1 µg/mL LPS), AF-1 group (100 μmol/L AF-1), LPS+AF-1 group (2 h of 100 μmol/L AF-1 pretreatment before LPS addition), and LPS+AF-1+anti-UGBP group (30 min of anti-UGBP antibody pretreatment before successive treatments with AF-1 and LPS). IL-10 concentration in the supernatants was detected by ELISA assay, and the level of IL-10 mRNA expression in macrophage was detected by using RT-PCR method. The results showed that AF-1 significantly increased LPS-induced IL-10 secretion in RAW264.7 cells in a dose dependent way, and up-regulated its mRNA level. Anti-UGBP antibody pretreatment attenuated the augmented effect of AF-1 on LPS-induced IL-10 secretion and gene expression. These results suggest that AF-1 promotes LPS-induced IL-10 secretion from macrophages, and this effect is mediated by UGBP.
Sheng li xue bao: [Acta physiologica Sinica] 08/2013; 65(4):363-9.
[show abstract][hide abstract] ABSTRACT: To prepare anti-mouse uteroglobin binding protein (mUGBP) polyclonal antibody, two polypeptides were synthesized based on the bioinformatics analysis of mUGBP, and New Zealand white rabbits were immunized separately with each peptide coupled with keyhole limpet hemocyanin (KLH). The data indicate that a 13-amino acid polypeptide (positions 221st-233rd) was able to generate anti-peptide antibodies. The titer of the antisera detected with ELISA was 1:10(8). The antisera were then purified with immuno-affinity chromatography to obtain antibodies. Western blot analysis of mUGBP expressed as a fusion protein with a green fluorescent protein (GFP) was performed on the cell lysates of COS-1 cells with the purified antisera, suggesting that the antisera specifically recognized UGBP. By immunohistochemistry and indirect immunofluorescence analysis, we examined the expression of UGBP in the lung tissues from a patient undergoing surgical lung resection for a tumor and from normal mouse lung tissue, and found for the first time that UGBP protein was widely expressed in both mouse and human lung tissue with the most abundant expression in bronchial epithelial cells. These results suggest that the antigen epitopes of mUGBP are well predicted by using bioinformatics analysis. We have obtained anti-mUGBP polyclonal antibody, which will be useful for further investigation.
Sheng li xue bao: [Acta physiologica Sinica] 04/2013; 65(2):217-223.
[show abstract][hide abstract] ABSTRACT: L-glutamate (Glu) is an excitatory neurotransmitter in the mammalian central nervous system. Relatively much attention has been paid to functional expression of Glu signaling molecules in peripheral tissues very recently. The present study tested the hypothesis that the activation of group I metabotropic glutamate receptor (mGluRI) in neutrophils stimulated neutrophils adherence to endothelial cells by increasing the surface expression of certain adhesion molecules. Peripheral blood was obtained by venipuncture from healthy donors, and the neutrophils were isolated by Ficoll-Hypaque gradient centrifugation. Neutrophils floating into DMEM/F12 culture medium containing 10% fetal bovine serum were then used immediately. Immunocytochemistry and real-time quantitative RT-PCR were used to detect the expression of mGluRI (mGluR1 and mGluR5) in neutrophils. The adherence of neutrophils to cultured human normal umbilical vein endothelial cells (HUVE-12) was measured by the colorimetric method. Cell surface expression of adhesion molecule CD11a in the neutrophils was determined by flow cytometry. Immunocytochemistry and real-time quantitative RT-PCR showed that mGluR1 and mGluR5 were constitutively expressed in neutrophils. Application of mGluRI agonist S-3,5-dihydroxyphenylglycine (S-DHPG) (1x10(-8)-1x10(-6) mol/L) showed a dose-dependent stimulatory effect on the adherence of neutrophils to HUVE-12 (P<0.05 or P<0.01), with a maximum effect at 1x10(-6) mol/L (P<0.01). Incubations as short as 30 min were sufficient to induce increased adherence after the beginning of S-DHPG treatment. Following time extension (0.5-5 h), S-DHPG (1x10(-6) mol/L) increased the rate of neutrophils adhesion to HUVE-12 with a maximum effect at 0.5 h (P<0.01). However, a time-dependent effect of S-DHPG on the rate of neutrophils adhesion to HUVE-12 was not observed during the experimental period. 1x10(-6) mol/L of S-DHPG also induced an increased surface expression of adhesion molecule CD11a (P<0.01) when neutrophils were preincubated with 1x10(-6) mol/L of S-DHPG for 1 h. Furthermore, the specific mGluRI antagonist (RS)-alpha-methyl-4-carboxyphenylglycine ((+/-)-MCPG, 0.5 mmol/L) significantly abolished the stimulatory effect of S-DHPG (1x10(-6) mol/L) on the adherence of neutrophils to HUVE-12 (P<0.01). These results suggest that the activation of mGluRI in neutrophils results in increased adhesion molecule CD11a expression and thereby promotes the adherence of neutrophils to endothelial cells.
Sheng li xue bao: [Acta physiologica Sinica] 06/2010; 62(3):219-24.
[show abstract][hide abstract] ABSTRACT: This study aimed to examine effects of adjunctive baicalin therapy to ampicillin for experimental bacterial meningitis in rabbits. After Escherichia Coli inoculation, mean leukocyte counts, concentrations of protein, tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1) and lactate in cerebrospinal fluid (CSF), brain water content and mean arterial and intracranial pressures substantially increased in the meningitis group. Ampicillin alone for 5 h markedly exacerbated the enhanced leukocyte counts and protein concentration, and showed no significant effect on the elevated CSF TNF-alpha, IL-1 and lactate concentration, mean arterial and intracranial pressures, and brain water content. Baicalin (7-D-glucuronic acid-5,6-dihydroxyflavone, C(21)H(18)O(11)) completely counteracted ampicillin-induced exacerbation, and further alleviated the enhanced mean leukocyte counts and protein concentration when combined with ampicillin. Adjunctive baicalin also significantly ameliorated the elevated CSF TNF-alpha, IL-1 and lactate concentration, mean arterial and intracranial pressures, and brain water content. Baicillin, as an adjunctive treatment exerted multiple therapeutic effects in experimental bacterial meningitis.
[show abstract][hide abstract] ABSTRACT: Asymmetric dimethylarginine (ADMA), a major endogenous inhibitor of nitric oxide synthase, is recently defined as an independent cardiovascular risk factor. Tissue factor (TF) expression and procoagulant activity (PCA) of peripheral monocytes are increased in patients with acute coronary syndromes (ACS), which resulted in blood procoagulant state tending to thrombus formation. In the present study, we tested the hypothesis that ADMA contribute to TF expression of peripheral monocytes in ACS. Twenty patients with unstable angina (UA), 20 patients with stable angina (SA) and 20 control subjects were recruited. Monocytic cell line THP-1 was incubated with different concentrations of ADMA (1-10microM) for various periods (6-24h). Our results showed that plasma level of ADMA in patients with UA was significantly higher than those in patients with SA or in the control group, and positively correlated with TF antigen level and PCA of circulating monocytes. Adjusting for all patient characteristics, we confirmed these findings in multivariate regression analyses. In cultured THP-1 cells, ADMA transcriptionally upregulated both TF antigen expression and PCA in a concentration-dependent manner. The experiments using nuclear factor-kappaB (NF-kappaB) inhibitor and transient transfection with wild-type and mutated TF promotor constructs showed that the NF-kappaB is an important transcriptional regulator of ADMA-induced TF expression. Our results suggest that elevated plasma level of ADMA induces TF expression in monocytes via NF-kappaB-dependent pathway, which contributes to procoagulant phenotype of circulating monocytes in ACS.
[show abstract][hide abstract] ABSTRACT: 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 concentrateion, 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.
Sheng li xue bao: [Acta physiologica Sinica] 07/2008; 60(3):403-8.
[show abstract][hide abstract] ABSTRACT: Antiflammin-1 (AF-1) is a synthetic nonapeptide with a similar sequence to the conserved sequence of CC10 secreted by lung Clara cells. Studies suggest that it is potent inhibitor of inflammation. We investigated the effects and possible mechanisms of AF-1 on LPS-induced alveolar macrophage (AM) activation in vitro. AMs harvested from the BALF of Sprague-Dawley (SD) rat were treated with various concentrations of AF-1 both simultaneously and after LPS stimulation. The concentrations of the cytokines IL-1beta, IL-6, and IL-10 in the supernatant were detected by an enzyme-linked immunosorbent assay. The mRNA expression levels of these cytokines in AMs were analyzed using quantitative RT-PCR. To investigate more fully the possible mechanisms by which AF-1 modulates the expression of cytokines, cells were pretreated with anti-IL-10 antibody. Toll-like receptor-4 (TLR-4) expression on the cell surface was also detected using flow cytometry. The results showed that AF-1 suppressed mRNA expression and protein production of IL-1beta and IL-6, while it promoted IL-10 expression in LPS-stimulated AMs, in a dose-dependent manner. The inhibitory effects of AF-1 on IL-1beta were significantly decreased when endogenous production of IL-10 was blocked. AF-1 also showed an effect on downregulated TLR-4 expression in LPS-stimulated AMs. The data show for the first time that AF-1 modulates the AM response to LPS by regulating TLR-4 expression and upregulating IL-10 secretion, which could be another important mechanism in the AF-1 inhibiting effect on inflammation.
Cell Biology International 06/2008; 32(9):1108-15. · 1.64 Impact Factor
[show abstract][hide abstract] ABSTRACT: Free fatty acids (FFAs) regulate insulin secretion in a complex pattern and induce pancreatic beta-cell dysfunction in type 2 diabetes. Voltage-dependent Ca2+ channels (VDCC) in beta-cells play a major role in regulating insulin secretion. The aim of present study is to clarify the action of the FFA, linoleic acid, on VDCC in beta-cells. The VDCC current in primary cultured rat beta-cells were recorded under nystatin-perforated whole-cell recording configuration. The VDCC was identified as high-voltage-gated Ca2+ channels due to there being no difference in current amplitude under holding potential between -70 and -40 mV. Linoleic acid (10 microM) significantly inhibited VDCC currents in beta-cells, an effect which was fully reversible upon washout. Methyl-linoleic acid, which does not activate G protein coupled receptor (GPR)40, neither did alter VDCC current in rat beta-cells nor did influence linoleic acid-induced inhibition of VDCC currents. Linoleic acid-induced inhibition of VDCC current was not blocked by preincubation of beta-cells with either the specific protein kinase A (PKA) inhibitor, H89, or the PKC inhibitor, chelerythrine. However, pretreatment of beta-cells with thapsigargin, which depletes intracellular Ca2+ stores, completely abolished linoleic acid-induced decrease in VDCC current. Measurement of intracellular Ca2+ concentration ([Ca2+](i)) illustrated that linoleic acid induced an increase in [Ca2+](i) and that thapsigargin pretreatment inhibited this increase. Methyl-linoleic acid neither did induce increase in [Ca2+](i) nor did it block linoleic acid-induced increase in [Ca2+](i). These results suggest that linoleic acid stimulates Ca2+ release from intracellular Ca2+ stores and inhibits VDCC currents in rat pancreatic beta-cells via Ca2+-induced inactivation of VDCC.
Journal of Endocrinology 03/2008; 196(2):377-84. · 4.06 Impact Factor
[show abstract][hide abstract] ABSTRACT: We previously reported that vasoactive intestinal peptide (VIP) promoted synthesis of phosphatidylcholine (PC) in alveolar type II (ATII) cells. But the intracellular mechanism for this effect was unknown. In this work, we investigated the intracellular signal transduction pathway for VIP promoted synthesis of PC, the major lipid component of pulmonary surfactant (PS), by using an antagonist of VIP receptors, inhibitor of protein kinase C (PKC) and antisense oligonucleotides (AS-ODN) for c-fos oncogene. Our results showed that: 1 in circle [D-P-Cl-Phe(6)-Leu(17)]-VIP (10(-6) mol/l), an antagonist of VIP receptors, could decrease the quantity of [(3)H] choline incorporation, microsomal choline-phosphate cytidylyltransferase (CCT) mRNA expression and CCT activity induced by VIP (10(-8) mol/l) in cultured lung explants to the control levels; 2 in circle VIP (10(-8) mol/l) upregulated c-Fos protein expression in ATII cells. AS-ODN for c-fos oncogene (9x10(-6) mol/l) could block the elevation of [(3)H] choline incorporation, microsomal CCT mRNA expression and CCT activity induced by VIP in cultured lung explants and in ATII cells; 3 in circle H7 (10(-5) mol/l), a PKC inhibitor could also reduce VIP induced [(3)H] choline incorporation, microsomal CCT mRNA expression and CCT activity in cultured lung explants and in ATII cells. These results demonstrated that VIP receptors, PKC and c-Fos protein played important roles in the signaling pathway through which VIP promoted the synthesis of PC.
[show abstract][hide abstract] ABSTRACT: To examine the possible protective effect of ginsenoside Rg1, an active component of ginseng, on lung injury caused by glutamate in vivo.
The lungs of mice receiving glutamate (0.5 g/kg) and/or ginsenoside Rg1 (0.03 g/kg) via intraperitoneal administration were collected. The indexes of lung wet weight/ body weight ratios (LW/BW), lung wet/dry weight ratios (W/D), heart rate (HR), and breathing rate (BR) were determined. The activity of nitric oxide synthase (NOS), xanthine oxidase (XOD), superoxide dismutase (SOD), catalase (CAT), the content of NO, and malondialdehyde in the lung homogenate were measured.
Treatment with glutamate for 2 h increased LW/BW, W/D, HR, and BR. These changes were nearly abolished by pretreatment with ginsenoside Rg1 for 30 min before glutamate injection. An analysis of the lung homogenate demonstrated the protective effect as evidenced by the inhibition of NOS (12%) and XOD (50%) inactivity, the enhanced activity of SOD (20%) and CAT (25%).
Ginsenoside Rg1 has a potential protective role in lung diseases associated with glutamate toxicity.
[show abstract][hide abstract] ABSTRACT: To investigate the possible injury induced by glutamate in the lung.
The lung wet weight/body weight (LW/BW), lung wet/dry weight (W/D), the content of cells and the total protein (TP) in bronchoalveolar lavage fluid (BALF) were determined together with the micromorphology observation.
(1) The LW/BW, W/D, the content of white blood cells, red blood cells and TP in BALF increased in a dose dependent manner 2 hours after the administration of the glutamate (0.50 - 0.75 g/kg). (2) Examination of histological sections showed the presence of lung inflammation charactered by neutrophils recruitment 2 hours after the glutamate administration. (3) The increase of W/D caused by glutamate (0.50 g/kg) was nearly abolished by pre-treatment with MK801 (a specific blocker of NMDA receptor, 0.1 mg/kg) for 30 minutes (P<0.05).
Glutamate can cause the acute lung injury through the activation of NMDA receptor in vivo.
Zhong nan da xue xue bao. Yi xue ban = Journal of Central South University. Medical sciences 02/2007; 32(1):78-81.
[show abstract][hide abstract] ABSTRACT: In the present study, we investigated the effects of vasoactive intestinal peptide (VIP) on wound healing of bronchial epithelium. Wound healing of the mechanical damaged human bronchial epithelial cells (HBEC) was observed in the absence or presence of VIP. Effects of VIP on chemotactic migration, cell proliferation of HBEC were also tested. HBEC chemotaxis was assessed by the blind well chamber technique, the cell cycle was determined by flow cytometry, and cell proliferation was determined by measuring the expression of proliferating cell nuclear antigen Ki67. Effects of VIP on epithelial E-cadherins protein and mRNA were also measured by immunohistochemistry and RT-PCR. The results showed that VIP accelerated the recovery of wound area of HBEC. VIP increased the migration and proliferation of HBEC, and these effects were blocked by a VPAC1 receptor antagonist. VIP also increased the expression of E-cadherin mRNA and protein in HBEC, suggesting that protective effects of VIP on wound healing may be related to its ability to increase the expression of E-cadherin. In conclusion, VIP has protective effects against human bronchial epithelial cell damage, and the beneficial effects of VIP might be mediated, at least in part, by VPAC1, and associated with increased expression of E-cadherin.
[show abstract][hide abstract] ABSTRACT: A complex network of regulatory neuropeptides controls airway inflammation reaction, in which airway epithelial cells adhering to and activating leukocytes is a critical step. To study the effect of intrapulmonary regulatory peptides on adhesion of polymorphonuclear leukocytes (PMNs) to bronchial epithelial cells (BECs) and its mechanism, several regulatory peptides including vasoactive intestinal peptide (VIP), epidermal growth factor (EGF), endothelin-1 (ET-1) and calcitonin gene-related peptide (CGRP), were investigated. The results demonstrated that VIP and EGF showed inhibitory effects both on the secretion of IL-1, IL-8 and the adhesion of PMNs to BECs, whereas ET-1 and CGRP had the opposite effect. Anti-intercellular adhesion molecule-1 (ICAM-1) antibody could block the adhesion of PMNs to ozone-stressed BECs. Using immunocytochemistry and reverse transcription-polymerase chain reaction (RT-PCR), it was shown that VIP and EGF down-regulated the expression of ICAM-1 in BECs, while ET-1 and CGRP up-regulated ICAM-1 expression. NF-kappaB inhibitor MG132 blocked ICAM-1 expression induced by ET-1 and CGRP. Furthermore, in electric mobility shift assay (EMSA), VIP and EGF restrained the binding activity of NF-kappaB to the NF-kappaB binding site within the ICAM-1 promoter in ozone-stressed BECs, while CGRP and ET-1 promoted this binding activity. IkappaB degradation was consistent with NF-kappaB activation. These observations indicate that VIP and EGF inhibit inflammation, while ET-1 and CGRP enhance the inflammation reaction.
[show abstract][hide abstract] ABSTRACT: To explore the neuro-protective effect and mechanism of qingkailing injection (QKL) against cerebral injury caused by E. coli-meningitis (CM).
The CM model rabbits were treated by ampicillin with QKL as adjuvant. The leukocyte count and protein content in cerebral spinal fluid (CSF), the contents of water, sodium, potassium and calcium in cerebral tissues were measured before, 16 h and 26 h after Bacillus coli injection respectively. The expression of matrix metalloproteinase-9 (MMP-9) was determined at the same time.
Adjunctive treatment with QKL can not only inhibit the increase of leukocyte cells, protein content in CSF, and water, sodium, calcium content in cerebral tissues, but also the decrease of potassium content revealed during simple antibiotic treatment. It also can decrease the expression of MMP-9 in cerebral tissues of rabbits with CM.
As an adjunctive treatment, QKL can prevent transient inflammatory reaction and aggravation of brain injury in CM induced by simple antibiotic treatment, its mechanisms might relate with calcium antagonism and attenuation of MMP-9 expression in brain tissues.
Zhongguo Zhong xi yi jie he za zhi Zhongguo Zhongxiyi jiehe zazhi = Chinese journal of integrated traditional and Western medicine / Zhongguo Zhong xi yi jie he xue hui, Zhongguo Zhong yi yan jiu yuan zhu ban 08/2005; 25(7):633-6.
[show abstract][hide abstract] ABSTRACT: To investigate the effect of vasoactive intestinal peptide (VIP) on pulmonary surfactants (PS) phospholipid synthesis in cultured lung explants.
Lung explants were cultured with serum-free medium, [methyl-3H]choline incorporation, total phospholipid, phosphatidylcholine, activity of choline-phosphate cytidylyltransferase (CCT) and CCTalpha mRNA level in lung explants were determined.
(1) VIP (10(-10)-10(-7) mol/L) for 16 h promoted [methyl-3H]choline incorporation in dose dependence and VIP (10(-8) mol/L) for 2 h-16 h promoted [methyl-3H]choline incorporation in time dependence. (2) VIP (10(-8) mol/L) enhanced the contents of total phospholipids and phosphatidylcholine in lung explants. (3) VIP (10(-10)-10(-7) mol/L) elevated microsomal CCT activity of lung explants in dose dependence. (4) VIP (10(-8) mol/L) increased expression of CCTalpha mRNA in lung explants and alveolar type II cells (ATII). (5) [D-P-Cl-Phe(6)-Leu(17)]-VIP (10(-6) mol/L), a VIP receptors antagonist, abolished the increase of [3H]choline incorporation, microsomal CCT activity and CCTalpha mRNA level induced by VIP (10(-8) mol/L) in lung explants.
VIP could enhance synthesis of phosphatidylcholine, the major component of pulmonary surfactants by enhancing microsomal CCT activity and CCTalpha mRNA level via VIP receptor-mediated pathway.
[show abstract][hide abstract] ABSTRACT: We have previously shown that the binding of integrins with extracellular matrix component fibronectin (Fn) can improve the ability of bronchial epithelial cells (BECs) in resisting oxidant injury by up-regulating the activity of catalase and increasing the content of GSH. However, the molecular mechanism or its signaling pathway of this protection is still unclear. In order to examine the intracellular signaling mechanism activated by Fn-integrin binding reaction, the present study investigated the mRNA expression of catalase in primary cultured rabbit BECs using RT-PCR based on a cell-injury model made with ozone exposure. The product bands of target gene CAT were checked with Southern blot and oligonucleotide probe hybridization. The results showed that Fn (10 microg/ml) promoted the catalase mRNA transcription (P<0.01). This effect was abolished either by protein-tyrosine kinase inhibitor genistein or calmodulin inhibitor W(7) (P<0.01). These results indicate that the promotion of catalase activity induced by Fn-integrin reaction is partly due to the elevation of catalase mRNA transcription, and that its signalling are possibly relevant to tyrosine phosphorylation or calmodulin pathway.
Sheng li xue bao: [Acta physiologica Sinica] 06/2004; 56(3):365-8.
[show abstract][hide abstract] ABSTRACT: To explore the role of intrapulmonary neuropeptides in the development of airway hyperresponsiveness, we established an animal model of airway hyperresponsiveness (AHR) in rabbits by using ozone exposure. With the model, after test of the mechanics of respiration and bronchoalveolar lavage assay, the levels of vasoactive intestinal peptide (VIP) and calcitonin gene-related peptide (CGRP) in the lungs were determined by radioimmunoassay, and the expression of mRNA coding receptors of these two neuropeptides was evaluated by reverse transcriptional-polymerase chain reaction (RT-PCR). At the same time, the distribution of VIP receptor-1 (VIPR1) and CGRP receptor-1 (CGRPR1) in lung tissues and its time-course were examined by in situ hybridization. The results showed: (1) in ozone-stressing groups, airway resistance increased significantly and typical inflammatory pathological changes were observed in pulmonary tissue slides, including neutrophil and eosinophil infiltration, mucus exudation and bronchial epithelial cells (BECs) shedding; (2) with elongation of ozone exposure, the levels of VIP and CGRP in the lungs increased at first, reaching a peak on d 2 to 4, then decreased slowly, and CGRP peaked somewhat earlier than VIP; (3) mRNA expression of the two neuropeptide receptors in the lungs changed in a similar manner like VIP and CGRP, but the high level of mRNA expression of VIPR1 lasted longer than that of CGRPR1; and (4) in situ hybridization for neuropeptide receptors demonstrated that, in unstressed control, VIPR1 and CGRPR1 positive cells appeared in the airway epithelium, pulmonary interstitial and focal areas of airway and vascular smooth muscles. With the elongation of ozone exposure, hybridization stained deeper and the majority of positive cells were located around the vessels and bronchus except a few in the alveoli. At 8 d, only a small number of positive cells were seen in the lungs. From the results, it is concluded that ozone-stressing can induce the development of AHR, in which VIP and CGRP may play important roles. That implies, through binding to CGRPR1, CGRP stimulates an early inflammation response which contributes in cleaning up of irritants, while VIP exerts a later dampening of pulmonary inflammation response. These two neuropeptides may play sequential and complementary roles in the development of AHR.
Sheng li xue bao: [Acta physiologica Sinica] 05/2004; 56(2):137-46.
[show abstract][hide abstract] ABSTRACT: To study the influence of VIP on the expression of SP-A and its intracellular signal transduction pathway.
The influence of VIP on the expression of SP-A was studied by immunohistochemistry and RT-PCR. The intracellular signal transduction pathway was further investigated by using receptor antagonist, protein kinase inhibitor and antisense oligonucleotides.
(1) VIP(10(-8) mol/L) enhanced SP-A protein expression in alveolar type II cells (ATII) and increased the content of SP-A mRNA in lung tissue. (2) VIP receptor antagonist [D-P-C1-Phe (6)-Leu (17)]-VIP (10(-6) mol/L) could suppress the VIP-induced expression of SP-A protein and SP-A mRNA. (3) c-fos antisense oligonucleotides (9 x 10(-6) mol/L) could inhibit the VIP-induced expression of SP-A protein and SP-A mRNA. (4) Protein kinase C(PKC) inhibitor H7 (10(-5) mol/L) could also depress the V1P-induced SP-A protein and SP-A mRNA.
VIP can up-regulate the expression of SP-A through its receptor. PKC and c-fos protein play important roles in the intracellular signal transduction pathway through which VIP induces the expression of SP-A.
Zhongguo ying yong sheng li xue za zhi = Zhongguo yingyong shenglixue zazhi = Chinese journal of applied physiology 05/2004; 20(2):117-20.
[show abstract][hide abstract] ABSTRACT: To determine the possible involvement of vasoactive intestinal peptide (VIP) in the development of airway hyper responsiveness (AHR).
Twenty-five rabbits were randomly divided into five groups (5 animals each). Four groups were exposed to 2.0 ppm ozone 1 h/day for 1 (group B(0)), 2 (group B(1)), 4 (group B(2)), and 8 (group B(3)) days, respectively. The control group (group A) breathed only filtered room air. The changes of the VIP level and the mRNA expression of VIP receptor 1 (VIPR1) in the lung were detected at various ozone-stressing time points. In situ hybridization was performed to examine the distribution of VIPR1 in the lung.
(1) The concentration of VIP in the lung increased slowly and were maximal at day 4, then returned to the normal level. (2) The changing pattern of the VIPR1 mRNA in the lung was similar to those observed for VIP. Increases in VIPR1 mRNA were detectable by 1 day and maximal by 2 - 4 days, and then decreased slowly. (3) In group A, VIPR1 was expressed on airway epithelium, in pulmonary interstitial and focal areas of airways and vascular smooth muscles. By days 2 to 4, hybridization staining increased and the majority of VIPR1-positive cells was located in the perivascular and peribronchiolar area. On day 8, very few positive cells were seen in the lung.
VIP may play an important role in the development of AHR by binding with VIPR1.
Zhonghua jie he he hu xi za zhi = Zhonghua jiehe he huxi zazhi = Chinese journal of tuberculosis and respiratory diseases 05/2004; 27(4):224-8.