Intercellular Adhesion Molecule-1 Protein Research Articles

Effect and mechanism of emodin on cholestatic hepatitis

To explore the therapeutic effect and mechanism of emodin on cholestatic hepatitis. Rats were divided into 5 groups: 1 group was untreated, the other 4 groups were treated with alpha-naphthylisothiocyanate (ANIT), ANIT and emodin, ANIT and ursodeoxycholic acid, or ANIT and dexamethasone, respectively. At 24 h, 48 h and 72 h after the treatment, NF-kappa B, early growth response factor-1 (Egr-1), cytokine-induced neutrophil chemoattractant 1 (CINC-1), macrophage inflammatory protein 2 (MIP-2), intercellular adhesion molecule 1 (ICAM-1),tumor necrosis factor alpha (TNF alpha) and interleukin-6 (IL-6) were assayed by immunohistochemistry, real-time PCR , western-blot and ELISA. The level of malondialdehyde (MDA), superoxide Dismutase(SOD) and myeloperoxidase (MPO) were assayed by thiobarbituric acid method, xanthine oxidase method and colorimetric method, respectively. (1) Compared to the controls, emodin had a notable effect on total bilirubin (TB), direct bilirubin (DB), alanine aminotransferase (ALT) at all time points (all P less than 0.05). Compared to ursodeoxycholic acid, emodin had a notable effect on TB and DB at 24 h after the treatments, however, after 48 h, emodin had a notable effect only on TB (all P less than 0.05). Compared to Dexamethasone, emodin had a notable effect on TB at 48 h time point, and it had a notable effect on ALT at all time points (all P less than 0.05). (2) The nuclei NF-kappa B p65 staining was significantly increased at 24 h and 48 h after ANIT treatment (all P less than 0.05), and emodin treatment could block the increase (all P less than 0.05). (3) Egr-1 mRNA level was not affected by emodin treatment (P more than 0.05); levels of CINC-1, MIP-2 mRNA and ICAM-1 protein were significantly decreased after emodin treatment (all P less than 0.05). (4) The levels of TNF alpha and IL-6 were decreased after emodin treatment(all P less than 0.05). (5) The levels of MDA at all time points and MPO at 24 h, 48 h time points were notably down-regulated by emodin treatment, while the level of SOD was markedly elevated at all time points after emodin treatment (all P less than 0.05). Emodin treatment can reduce the levels of TB, DB and ALT in ANIT induced-cholestatic hepatitis. The effect may be due to inhibition of NF-kappa B signal pathway.

Protection of carbon monoxide-releasing molecule against lung injury induced by limb ischemia-reperfusion

To observe the role and mechanism of CO-releasing molecule (CORM)-2 in lung injury induced by ischemia-reperfusion (IR) of hind limbs in rats. A rat model of lung injury induced by IR of hind limbs was established. A total of 40 Sprague Dawley (SD) rats were randomly divided into 5 groups (n equal to 8): sham, sham + CORM-2, IR, IR + CORM-2 and IR + dimethyl sulfoxide (DMSO). Rats in the IR group received hind limb ischemia for 2 hours and reperfusion for 2 hours, rats in the sham group underwent sham surgery without infrarenal aorta occlusion, rats in the IR+CORM-2 group and in the sham + CORM-2 group were given CORM-2 (10 micromol/kg intravenous bolus) 5 minutes before reperfusion or at the corresponding time points, while rats in the IR + DMSO group was treated with the same dose of vehicle (DMSO) at the same time. The lung tissue structure, polymorphonuclear neutrophil (PMN) count, wet-to-dry weight ratio (W/D), malondialdehyde (MDA) content, myeloperoxidase (MPO) activity, intercellular adhesion molecule-1 (ICAM-1) expression,IkBa degradation and nuclear factor (NF)-kB activity in the lungs were assessed. As compared with the sham group, lung PMNs number, W/D, MDA content, MPO activity, ICAM-1 expression and NF-kB activity significantly increased in the IR group, but the level of IkBa decresed (P less than 0.01). Compared with the IR group, lung PMNs number, W/D, MDA content, MPO activity and ICAM-1 expression significantly decreased in the IR+COMR-2 group (P less than 0.01), while the level of IkBa increased. These data demonstrate that CORM-2 attenuates limb IR-induced lung injury through inhibiting ICAM-1 protein expression, NF-kB pathway and the leukocytes sequestration in the lungs following limb IR in rats, suggesting that CORM-2 may be used as a therapeutic agent against lung injury induced by limb IR.

Positive effects of the middle layer of Phyllostachys nigra var. henonis (PN), Bambusae Calulis in Taeniam, on asthma murine model through down-regulated ICAM-1 of BMMC (36.12)

Abstract The middle layer of Phyllostachys nigra var. henonis (PN), Bambusae Calulis in Taeniam, has been used for cough and sputum for a long time. Cough is one of the major symptoms of asthma. However, there were few of scientific investigation about PN. To investigate the positive effect of PN on asthma, we measured the production of IL-4 of bronchoalveolar lavage fluid (BalF), Immunoglobulin E (IgE) level of serum and immune cell infiltration at lung tissue by HE stain in ovalbumin (OVA) induced asthma murine model (Balb/C, female, 6 weeks). In asthma model, there was IL-4 of BalF decreased by PN, however, it was not significantly. The IgE induced by OVA in serum significantly decreased by PN (40 mg/kg). Furthermore, we observed the decrease of immune cell infiltration up-regulated by OVA in lung tissue. We focused on decrease of cell infiltration by PN. Intercellular adhesion molecule-1 (ICAM-1) and L-selectin regulate IgE production by controlling mast cell accumulation at sites of inflammation. And then we investigated the mRNA and protein levels of ICAM-1 and L-selectin in bone marrow mast cells (BMMC). BMMC were incubated with 10 ng/ml of TNF-alpha fnand IL-3 plus 1, 10 and 100 £gg/ml of PN for 4 hours. The mRNA and protein level were measeured by using RT-PCR and Fluorescence activated cell sorter (FACS). PN had down-regulated both mRNA and protein of ICAM-1, however, no difference at mRNA and protein of L-selectin in BMMC. Together all things, PN has anti allergy effects on asthma, based on down-regulation of ICAM-1. Acknowledgements: This study was supported by a grant from Seoul R&BD Program, Republic of Korea.

Therapeutic effects of emodin on acute cholestatic hepatitis and mechanism thereof: experiment with rats

To investigate the therapeutic effects of emodin on acute cholestatic hepatitis and mechanism thereof. 96 SD rats were randomly divided into 4 groups to be treated with emodin, ursodeoxycholic acid, dexamethasone, or normal saline respectively for 4 days. On the 5th day gastric perfusion of alpha-naphthylisothiocyanate (ANIT) was performed to establish models of cholestatic hepatitis. 4 - 6 hours after the establishment of model the above mentioned agents were given continuously. 24, 48, and 72 hours after the model establishment blood samples were collected from abdominal aorta to examine the total bilirubin (TB), direct bilirubin (DB), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma glutamyltransferase (GGT), and total bile acid (TBA). Specimen of liver was collected to undergo pathological examination. PCR was used to detect the mRNA expression of cytokine-induced neutrophil chemoattractant 1 (CINC-1) and macrophage inflammatory protein 2(MIP-2), and Western blotting was used to detect the protein expression of intercellular adhesion molecule 1 (ICAM-1). Twenty-four rats treated with NS only were used as controls. The pathological changes of behaviors and liver of the emodin and ursodeoxycholic acid groups were all remarkably milder than those of other model groups. The levels of TB [(32.8 +/- 3.7) micromol/L, (61.0 +/- 16.4) micromol/L, (10.8 +/- 4.5) micromol/L], DB[ (26.03 +/- 3.10) micromol/L, (49.40 +/- 18.16) micromol/L, (8.04 +/- 3.03) micromol/L], and ALT [(314 +/- 50) U/L, (664 +/- 97) U/L, (200 +/- 60) U/L], at the time points 24, 48, and 72 hours, the 48 and 72 hours AST levels, the 48 hours ALP level, the 72 hours GGT level, and the 48 and 72 hours TBA levels of the emodin group were all significantly lower than those of the model group (all P < 0.05). The 24 and 48 hours TB levels, 24 hours DB and ALT, and 24, 72 hours TBA levels of the emodin group were all significantly lower than those of the ursodeoxycholic acid group (all P < 0.05). The 24, 48 hours TB and TBA levels, and the ALT, AST and GGT levels at all time points of the emodin group were all significantly lower than those of the dexamethasone group (all P < 0.05). The CINC-1 and MIP-2 mRNA expression levels and ICAM-1 protein expression levels at all time points of the emodin group were all significantly lower than those of the model group (all P < 0.05). Decreasing the levels of TB, DB and ALT in particular, emodin has a protective effect on cholestatic hepatitis. Its effects are quicker than ursodeoxycholic acid, and it has better effects on ALT, AST GGT, and TBA than dexamethasone. These effects may be due to inhibition of the activation of CINC-1, MIP-2, and ICAM-1.

Glutaredoxin Regulates Autocrine and Paracrine Proinflammatory Responses in Retinal Glial (Müller) Cells

Protein S-glutathionylation is a reversible redox-dependent post-translational modification. Many cellular functions and signal transduction pathways involve proteins whose cysteine-dependent activities are modulated by glutathionylation. Glutaredoxin (Grx1) plays a key role in such regulation because it is a specific and efficient catalyst of deglutathionylation. We recently reported an increase in Grx1 in retinae of diabetic rats and in rat retinal Müller glial cells (rMC-1) cultured in high glucose. This up-regulation of Grx1 was concomitant with NFkappaB activation and induction of intercellular adhesion molecule-1 (ICAM-1). This proinflammatory response was replicated by adenoviral-directed up-regulation of Grx1 in cells in normal glucose. The site of regulation of NFkappaB was localized to the cytoplasm, where IkappaB kinase (IKK) is a master regulator of NFkappaB activation. In the current study, inhibition of IKK activity abrogated the increase in ICAM-1 induced by high glucose or by adenoviral-directed up-regulation of Grx1. Conditioned medium from the Müller cells overexpressing Grx1 was added to fresh cultures of Müller or endothelial cells and elicited increases in the Grx1 and ICAM-1 proteins in these cells. These effects correlate with a novel finding that secretion of interleukin-6 was elevated in the cultures of Grx overexpressing cells. Also, pure interleukin-6 increased Grx1 and ICAM-1 in the rMC-1 cells. Thus, Grx1 appears to play an important role in both autocrine and paracrine proinflammatory responses. Furthermore, IKKbeta isolated from Müller cells in normal glucose medium was found to be glutathionylated on Cys-179. Hence Grx-mediated activation of IKK via deglutathionylation may play a central role in diabetic complications in vivo where Grx1 is increased.

Hypoxia influences CD40–CD40L mediated inflammation in endothelial and monocytic cells

The interaction between CD40 and its ligand (CD40L) has been implicated in the pathogenesis of atherosclerosis and is recognized as a central event in the development of immuno-inflammatory processes. Our previous studies have shown that the CD40–CD40L interaction modulates platelet, neutrophil, and endothelial reactive oxygen species (ROS) generation. Hypoxia, known to be associated with tissue ischemia and inflammation, also influences the ROS production and changes the cellular redox state. However, the effect of hypoxia on CD40–CD40L mediated vascular inflammation is unknown. We have investigated whether hypoxia influences CD40–CD40L mediated vascular inflammatory responses, ROS production, and cellular interactions. We found that hypoxia significantly enhances the inflammatory effect of CD40L in both endothelial and monocytic cells (THP1). CD40–CD40L interaction in the presence of hypoxia induces ROS production, the synthesis of an inflammatory adhesive protein intercellular adhesion molecule 1 (ICAM1) and activates stress response proteins (p38 MAP kinase and HSP27), indicating that CD40L mediates the induction of oxidative stress in these cells. Importantly, we found that the effects of CD40L can be transmitted between HUVECs and monocytic THP1 cells through intercellular CD40–CD40L interaction and these processes are augmented under hypoxia. Together, these data indicate that under hypoxic conditions the CD40–CD40L interaction significantly influences adhesion molecule expression, stress generation, actin polymerization, and monocytic adhesion to endothelial cells in addition to changes in signaling. In summary, we show that hypoxia can alter CD40–CD40L mediated endothelial–monocyte interaction, playing a significant role in vascular inflammation and cellular adhesion processes.

Rosiglitazone Attenuates the Severity of Sodium Taurocholate-induced Acute Pancreatitis and Pancreatitis-associated Lung Injury

In addition to the effect of regulating adipocyte differentiation and insulin sensitivity, peroxisome proliferator activated receptor-gamma (PPAR-gamma) ligands also exhibit anti-inflammatory effect. However, the mechanisms concerning how PPAR-gamma ligands affect acute pancreatitis and pancreatitis-associated lung injury have not been fully elucidated. This study investigated the effect of rosiglitazone, a PPAR-gamma ligand, on acute pancreatitis and pancreatitis-associated lung injury in the rat pancreatitis model induced by sodium taurocholate. Acute pancreatitis was induced by retrograde infusion of 5% sodium taurocholate (1 mL/kg) into the bile-pancreatic duct. Rosiglitazone (6 mg/kg) was administered via the femoral vein 30 min prior to the infusion of sodium taurocholate. The severity of pancreatitis was evaluated by serum amylase level, myeloperoxidase activity, and pathology. Pancreatitis-associated lung injury was evaluated by myeloperoxidase activity, the magnitude of pulmonary edema and pathology. Intercellular adhesion molecule-1 (ICAM-1) and tumor necrosis factor-alpha mRNA expression were studied using reverse transcriptase polymerase chain reaction. ICAM-1 protein expression was studied using Western blot analysis. Prophylactic administration of rosiglitazone attenuated (1) serum amylase level; (2) myeloperoxidase activity of pancreatic and pulmonary tissue; (3) expression of tumor necrosis factor-alpha and ICAM-1 in pancreas and lung; (4) pancreas and lung pathological damage. Our study demonstrated that rosiglitazone exerts a protective effect against sodium taurocholate-induced pancreatic and pulmonary injury.

Down-regulation of Protein and mRNA Expression of IL-8 and ICAM-1 in Colon Tissue of Ulcerative Colitis Patients by Partition-Herb Moxibustion

Our previous studies have demonstrated the efficacy of partition-herb moxibustion on ulcerative colitis (UC) rats. However, the mechanism of actions of partition-herb moxibustion is still unclear. Most Chinese acupuncturists believe that partition-herb improves the effect of moxibustion therapy. However, this argument lacks confirming experimental and clinical evidence. So, whether partition-herb does play a role in the mechanism of actions of partition-herb moxibustion was reported in this paper. A total of 123 patients were randomly divided into the partition-herb moxibustion group and the control group (partition-bran moxibustion group). Fourteen patients dropped out of the study. Finally, 109 patients finished the intervention. Sixty-one patients with UC received partition-herb moxibustion and 48 patients with UC received partition-bran moxibustion for 72 treatments, one treatment per day, every 12 treatments with an interval of 3 days. The expressions of interleukin-8 (IL-8) and intercellular adhesion molecule-1 (ICAM-1) in the colonic mucosa tissue in mild patients with UC were assayed by immunohistochemistry and RT-PCR. Histology of the colon also was observed at entry and after 72 treatments. Clinical therapeutic effect in partition-herb moxibustion was significantly better than those in partition-bran moxibustion (P < 0.05). Protein and mRNA expression of IL-8, ICAM-1 in the patients was inhibited by both partition-herb moxibustion and partition-bran moxibustion, of those the inhibition in the partition-herb moxibustion group was more obvious (P < 0.01). Partition-herb moxibustion was shown to significantly improve the histology of the colon, and partition-herb was shown to improve the therapeutic effect of moxibustion on treatment of UC patients.

Effect of Pinus massoniana bark extract on IFN-γ-induced ICAM-1 expression in HaCaT human keratinocytes

Aims of the study Pinus massoniana bark extract (PMBE) with known anti-oxidant activity is comprised of various flavonoids including several bioactive compounds. We found that PMBE contains 1.27% taxifolin, a well-studied compound with known anti-inflammatory activity. Therefore, in the present study, we evaluated the effects of PMBE and taxifolin on intercellular adhesion molecule-1 (ICAM-1) expression. Materials and Methods PMBE and taxifolin were prepared. After HaCaT cells were pre-treatmented with PMBE and taxifolin, HaCaT cells were treatmented with 1000 U/ml IFN-γ for 24 h. Results Treatment of HaCaT cells with 1000 U/ml IFN-γ for 24 h markedly increased ICAM-1 expression. However, PMBE pre-treatment (40 μg/ml for 24 h) significantly inhibited IFN-γ-induced ICAM-1 expression. In equal concentrations of taxifolin, PMBE-mediated inhibition of ICAM-1 mRNA and protein expression was greater than taxifolin mediated-inhibition, and the front on inhibition of ICAM-1 protein expression was 2.24–2.30-fold of the latter. When cells were treated with both compounds at a concentration of 40 μg/ml, PMBE-mediated inhibition of ICAM-1 mRNA was also greater than taxifolin-mediated inhibition and PMBE on inhibition of ICAM-1 protein expression was 2.60–3.00-fold the inhibition mediated by taxifolin. Conclusions PMBE including additional bioactive compounds may possibly synergize to inhibit transcription and translation of inducible ICAM-1expression and PMBE was greater than monomeric flavonoid taxifolin. These results indicate that PMBE exhibits great potential as a therapeutic treatment for inflammatory skin diseases.

Breviscapine, a traditional Chinese medicine, alleviates myocardial ischaemia reperfusion injury in diabetic rats

Objective — The aim of this study was to explore the effects of breviscapine on the expressions of intercellular adhesion molecule-1(ICAM-1), ATPase activities and oxidative stress in ischaemia-reperfused (I/R) myocardium of diabetic rats.Methods — Sprague Dawley rats were randomly divided into two groups (a diabetic group and a non-diabetic group), and each group divided into two subgroups including a control group and a breviscapine group. Reperfusion surgery was carried out in all rats. The contents of malonaldehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) in serum and myocardial tissues were measured.The activities of Na+-K+-ATPase, Mg2+-ATPase, Ca2+-ATPase in myocardial mitochondria were measured. The ICAM-1 protein expressions in myocardium were determined with the immunohistochemical method.Results — The activities of Na+-K+-ATPase, Mg2+-ATPase, Ca2+-ATPase were significantly increased in diabetic rats in the breviscapine group compared with the control group. Compared with the non-diabetic control group, the contents of MDA in serum and myocardium were significantly increased in the diabetic control group. Breviscapine led to a reduction of the contents of MDA in the diabetic and non-diabetic group. Compared with the non-diabetic control group, the activities of SOD and GSH-PX in the myocardium were significantly decreased in the diabetic control group. The activities of SOD and GSH-PX in serum and myocardium were increased in the diabetic and nondiabetic group after breviscapine treatment. Compared with the non-diabetic control group, the ICAM-1 protein expressions were increased significantly in the diabetic control group. Breviscapine decreased the ICAM-1 protein expression in the diabetic and the non-diabetic group.Conclusion — Breviscapine may have protective effects on myocardial ischaemia reperfusion injury of diabetic rats by scavenging oxygen free radicals, decreasing the expressions of ICAM-1 protein in myocardium and increasing the activities of Na+-K+-ATPase, Mg2+-ATPase, Ca2+-ATPase in myocardial mitochondria.

Cardiotrophin-1 induces intercellular adhesion molecule-1 expression by nuclear factor κB activation in human umbilical vein endothelial cells

In addition to elevated concentrations of cytokines, patients with congestive heart failure (CHF) show endothelial dysfunction and increased plasma concentrations of adhesion molecules like intercellular adhesion molecule-1 (ICAM-1). Furthermore, the concentration of cardiotrophin-1 (CT-1)--a cytokine of the interleukin-6 superfamily--is increased in CHF. We tested the hypothesis whether CT-1 is able to induce ICAM-1 in human umbilical vein endothelial cells (HUVEC). Furthermore we examined the signalling mechanisms of CT-1 mediated ICAM-1 expression. Confluent layers of HUVEC were incubated with increasing concentrations of CT-1 (5 to 100 ng/ml) for different periods. ICAM-1 mRNA was determined by real-time polymerase chain reaction (PCR) and ICAM-1 surface expression by fluorescence-activated cell sorter (FACS) analysis and soluble ICAM-1 (sICAM-1) in the culture supernatant by enzyme linked immunosorbent assay (ELISA). To clarify the signalling pathway of CT-1 induced ICAM-1 expression we used various inhibitors of possible signal transducing molecules, electromobility shift assay (EMSA) and Western blot analysis. CT-1 induced ICAM-1 mRNA (1.8 +/- 0.8 fold increase compared to unstimulated cells after 6 hours) and protein (1.4 +/- 0.2 fold increase compared to unstimulated cells after 48 hours) in HUVEC in a time- and concentration-dependent manner. EMSA experiments show that CT-1 causes nuclear factor (NF) kappaB activation. Because parthenolide could inhibit CT-1 induced ICAM-1 expression NFkappaB activation is required in this pathway. CT-1 did not activate extracellular signal regulated kinases (ERK), c-Jun N-terminal kinase (JNK) and p38. CT-1 is able to induce ICAM-1 in endothelial cells by NFkappaB activation. These results may explain in part elevated ICAM-1 concentrations in patients with CHF and endothelial dysfunction.

Quercetin inhibits IL-1 beta-induced ICAM-1 expression in pulmonary epithelial cell line A549 through the MAPK pathways

Quercetin is a herbal flavonoid derived from various foods of plant origin and widely used as a major constituent of nutritional supplements. Quercetin has been shown to have anti-inflammatory properties and can play a role in anti-inflammatory procedure. Intercellular adhesion molecule-1 (ICAM-1) is one of the important pro-inflammatory factors, especially in early phage of inflammation. However, the mechanisms regulating ICAM-1 expression by quercetin in human A549 cells were still unclear. In this study, the inhibitory effect of quercetin on ICAM-1 expression by interleukin-1 beta (IL-1 beta)-stimulated A549 cells was investigated, and the roles of mitogen-activated protein kinases (MAPK) pathways were explored. Quercetin attenuated IL-1 beta-induced expression of ICAM-1 mRNA and protein in a dose-dependent manner. The experiment suggested that quercetin actively inhibited inhibitory protein of nuclear factor-kappa B (I kappa B) degradation, and nuclear factor-kappa B (NF-kappa B) activity. The c-fos and c-jun, components of activator protein-1 (AP-1), were mediated by MAPK pathways. ERK and p38 were involved in the c-fos mRNA expression, and JNK was involved in the c-jun mRNA expression. The inhibitory effect of quercetin on ICAM-1 expression was mediated by the sequential attenuation of the c-fos and c-jun mRNA expressions. These inhibitory effects were partially inhibited by SB203580, a specific inhibitor of p38 MAPK, but not by PD98059, a specific inhibitors of extracellular signal-regulated kinase (ERK), and SP600125, a specific inhibitor of c-Jun-N-terminal kinase (JNK). Taken together, these results suggest that quercetin negatively modulating ICAM-1 partly dependent on MAPK pathways.

Dynamic changes of renin-angiotensin system, collagen I and intercellular adhesion molecule I in lung tissue of neonatal rats with hyperoxia-induced lung fibrosis

Objective To observe the dynamic changes of renin-angiotensinsystem,collagen I(CoI) and intercellular adhesion molecule 1(ICAM-1) in hmg tissue of neonatal rats with lung fibrosis induced by hyperoxia.Methods One hundred and twenty term neonatal Wistar rats were randomly assigned into model group and air control group.The model group was continuously exposed to hyperoxia (FiO2=0.9)for 21 days,and the air control group was exposed to room air(FiO2=0.21).On the Ist,3rd,7th,14th and 21st day of exposure,the subjects were sacrificed.And then,the protein levels of CoI,ICAM-1 were measured by enzyme-linked immunosorbentassay and angiotensinII(AngII) by radio-immunity technique,the activity of angiotensin-convertion enzyme(ACE) were measured by biochemistry analysator,and the mRNA expression of ACE,AngII,CoI was measured by RT-polymerase chain reaction.The changes of lung histomorphology were observed.Results The ACE,AngII,CoI and ICAM-1 protein levels of model group were (249.20±20.19)μg/g,(838.22±197.75)μg/g,(539.85±81.03) μg/g and (577.06±61.17)μg/g on the 14th day respectively and in.eased significantly as compared to the air control group (P＜0.05),and the ACE,AngII,CoI mRNA expression of modal group also increased signficantly on the 14th day (P＜0.05).The ACE,AngII,CoI and ICAM-1 protein levels of model group were(249.20±20.19)μg/g,(838.22±197.75)μ/g,(539.85±81.03)μg/g and (577.06±61.17)μg/g on the 21st day and increased to the peak respectively(P＜0.05),and the ACE,AngII and CoI mRNA expression had the same changes as well.The histopathological examination demonstrated different degrees of fibrosis in the model group.Conclusion The ACE,AngII,CoI and ICAM-1 protein levels and their mRNA expression were increased significantly on the 14th and 21st day in lung tissue of neonatal rats with lung fibrosis induced by hyperoxia.The renin-angiotensin system played a role in lung fibrosis induced by hyperoxia. Key words: Rat; Hyperoxia; Fibrosis; Renin-angiotensin system

Lipopolysaccharide-evoked activation of p38 and JNK leads to an increase in ICAM-1 expression in Schwann cells of sciatic nerves

Lipopolysaccharide is a major constituent of the outer membrane of Gram-negative bacteria. It activates monocytes and macrophages to produce cytokines such as tumor necrosis factor-alpha and interleukins IL-1beta and IL-6. These cytokines appear to be responsible for the neurotoxicity observed in peripheral nervous system inflammatory disease. It has been reported that, in the central nervous system, the expression level of intercellular adhesion molecule-1 (ICAM-1) was dramatically upregulated in response to LPS, as well as many inflammatory cytokines. ICAM-1 contributes to multiple processes seen in central nervous system inflammatory disease, for example migration of leukocytes to inflammatory sites, and adhesion of polymorphonuclear cells and monocytes to central nervous system cells. In the present study, we found that lipopolysacharide evoked ICAM-1 mRNA and protein expression early at 1 h post-injection, and the most significant increase was seen at 4 h. Immunofluorescence double-labeling suggested that most of the ICAM-1-positive staining was located in Schwann cells. Using Schwann cell cultures, we demonstrated that ICAM-1 expression in Schwann cells is regulated by mitogen-activated protein kinases, especially the p38 and stress-activated protein kinase/c-Jun N-terminal kinase pathways. Thus, it is thought that upregulation of ICAM-1 expression in Schwann cells may be important for host defenses after peripheral nervous system injury, and reducing the biosynthesis of ICAM-1 and other cytokines by blocking the cell signal pathway might provide a new strategy against inflammatory and immune reaction after peripheral nerve injury.

Benzo[a]pyrene induces intercellular adhesion molecule-1 through a caveolae and aryl hydrocarbon receptor mediated pathway

Toxicologic and epidemiologic studies have linked benzo[a]pyrene (B[a]P) exposure with cardiovascular diseases such as atherosclerosis. The mechanisms of action leading to these diseases have not been fully understood. One key step in the development of atherosclerosis is vascular endothelial dysfunction, which is characterized by increased adhesiveness. To determine if B[a]P could lead to increased endothelial adhesiveness, the effects of B[a]P on human endothelial cell intercellular adhesion molecule-1 (ICAM-1) expression was investigated. B[a]P was able to increase ICAM-1 protein only after pretreatment with the aryl hydrocarbon receptor (AhR) agonist β-naphthoflavone (β-NF). Knockdown of AhR by siRNA or treatment with AhR antagonist α-naphthoflavone (α-NF) eliminated the induction of ICAM-1 from B[a]P, confirming the necessity of AhR in this process. Likewise, B[a]P only increased monocyte adhesion to the vascular endothelium when cells were pretreated with β-NF. Experiments were done to define a signaling mechanism. B[a]P increased phosphorylation of MEK and p38-MAPK, and inhibitors to these proteins blunted the ICAM-1 induction. B[a]P was also able to increase AP-1 DNA binding and phosphorylation of cJun. Phosphorylation of cJun was disrupted by MEK and p38-MAPK inhibitors linking the signaling cascade. Finally, the importance of membrane microdomains, caveolae, was demonstrated by knockdown of the structural protein caveolin-1. Disruption of caveolae eliminated the B[a]P-induced ICAM-1 expression. These data suggest a possible pro-inflammatory mechanism of action of B[a]P involving caveolae, leading to increased vascular endothelial adhesiveness, and this inflammation may be a critical step in the development of B[a]P-induced atherosclerosis.

Mechanical Stress Upregulates Intercellular Adhesion Molecule-1 in Pulmonary Epithelial Cells

Background: Mechanicalventilation can affect the lung, causing edema and alveolar inflammation. Intercellular adhesion molecule-1 (ICAM-1) plays an important role in this inflammatory response. Objective: The aims of this study were to investigate whether cyclic cell stretch upregulates the production of ICAM-1 by human alveolar epithelium and to explore possible mechanisms of upregulation. Methods: Human type 2-like alveolar epithelial cells (A549 cells) were exposed to cyclic tensile strain via a four-point bending system, with strains of varying frequency (0.2, 0.5, and 1 Hz), duration (0, 1, 3, and 6 h), and magnitude (500, 1,000, and 2,000 microstrain). Strain was applied at varying frequency (0.2, 0.5, 1 Hz) but at constant time (3 h) and magnitude (1,000 microstrain), at varying duration (0, 1, 3, and 6 h) but at constant frequency (0.5 Hz) and magnitude (1,000 microstrain), or at varying magnitude (500, 1,000, and 2,000 microstrain) but at constant time (3 h) and frequency (0.5 Hz). Results: Mechanical loading induced ICAM-1 protein and mRNA production in a frequency- and duration-dependent manner. At the 3-hour time point, large loadings (1,000 or 2,000 microstrain) upregulated ICAM-1 protein production, but there was no statistically significant difference between these two groups (p > 0.05). PD98059, a specific inhibitor of extracellular signal-regulated kinase (ERK), and N-acetylcysteine (NAC), an antioxidant, partially abrogated the stretch-induced ICAM-1 protein upregulation at the 3-hour loading. Conclusion: Mechanical strain can upregulate ICAM-1 production. The response is frequency and duration dependent, which may involve both ERK pathways and reactive oxidant species production.

Delivery of Intercellular Adhesion Molecule-1 Antisense Oligonucleotides Using a Topical Hydrogel Tissue Sealant in a Murine Partial Nephrectomy/Ischemia Model

Ischemia/reperfusion injury is a leading cause of renal damage which can be improved with antisense oligonucleotide gene therapy. We have shown that polyethylene glycol (PEG) hydrogel, which also functions as a tissue sealant, is an effective topical delivery vehicle for oligonucleotides in a murine partial nephrectomy model. The objective of this study was to use and evaluate this method against intercellular adhesion molecule-1 (ICAM-1) to prevent tissue damage. Sixty mice underwent left upper pole partial nephrectomy with 45 minutes of warm ischemia, randomized to treatment with 50 microg ICAM-1 antisense oligonucleotides embedded in PEG hydrogel, no therapy, or sham surgery. Kidneys were harvested at 24 hours and 3, 4, and 5 days. The specimens were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) for ICAM-1 messenger ribonucleic acid (mRNA), immunohistochemical staining for ICAM-1 protein, and standard histology. At 24 hours, qRT-PCR and immunohistochemistry data showed a significant reduction in ICAM-1 mRNA and protein expression in the antisense group versus the ischemia group, but no difference at 3 to 5 days. Histologically there was reduced inflammation and necrosis in the cortex at 24 hours. The outer and inner medulla also showed improvement at 3 to 5 days in the antisense group as opposed to the ischemia group. Topical PEG hydrogel delivery of antisense ICAM-1 oligonucleotides demonstrated decreased ICAM-1 mRNA expression, reduced ICAM-1 protein staining, and decreased cellular damage. The application of gene therapy through this novel topical delivery system holds potential for a highly specific, localized method of preventing tissue damage after ischemia/reperfusion injury.

Aldosterone-Stimulated SGK1 Activity Mediates Profibrotic Signaling in the Mesangium

Several recent reports support the hypothesis that aldosterone contributes to the progression of renal injury. Mineralocorticoids increase the expression of serum- and glucocorticoid-inducible protein kinase 1 (SGK1), which is upregulated in several fibrotic diseases. It was hypothesized that SGK1 may mediate the effects of aldosterone on glomerular fibrosis and inflammation. In primary cultures of rat mesangial cells, aldosterone stimulated the expression, phosphorylation, and kinase activity of SGK1, as well as SGK1-dependent NF-kappaB activity. Furthermore, aldosterone augmented the promoter activity and protein expression of intercellular adhesion molecule-1 (ICAM-1), which modulates the inflammatory response, and the profibrotic cytokine connective tissue growth factor (CTGF) in an SGK1- and NF-kappaB-dependent manner. Similar to the in vitro results, uninephrectomized rats that were treated with aldosterone demonstrated increased glomerular expression of SGK1, ICAM-1, and CTGF proteins than untreated rats; these changes were accompanied by hypertension, glomerulosclerosis, and inflammation. In conclusion, these findings suggest that aldosterone stimulates ICAM-1 and CTGF transcription via the activation of SGK1 and NF-kappaB, effects that may contribute to the progression of aldosterone-induced mesangial fibrosis and inflammation.

Regulation of adhesion molecule expression in human endothelial and smooth muscle cells by omega-3 fatty acids and conjugated linoleic acids: Involvement of the transcription factor NF- κB?

We previously showed conjugated linoleic acids (CLA) inhibited TNF- α-induced monocyte (THP-1) adhesion to human umbilical vein endothelial cells (HUVEC) in vitro which involved an increase in platelet activating factor (PAF). Here we show adhesion molecule (ADM) regulation by fatty acids and the differing role of nuclear factor kappa B (NF- κB) activation in HUVEC and vascular smooth muscle cells (vSMC). CLA and omega-3 long-chain polyunsaturated fatty acids (PUFA) (FA) reduced TNF-ά-induced expression of ADMs (intercellular adhesion molecule-1 (ICAM-1); vascular cell adhesion molecule-1 (VCAM-1) but not E-selectin) on HUVEC and vSMC to different extents depending on FA type and concentration, cell type and method of analysis. I κBά phosphorylation in HUVEC and vSMC and transient transfection with NF- κB-luciferase reporter plasmid (HUVEC only) indicated differential NF- κB involvement during FA modulation ( cis-9, trans-11; trans-10, cis-12 and a 50:50 mix of both CLA isomers; eicosapentaenoic acid (EPA); docosahexaenoic acid (DHA)). TNF- α-induced ADM expression in both cell types by 2–10-fold. In HUVEC, CLA t10, c12 and CLA mix (50:50 mixture of CLA c9, t11 and t10, c12) and EPA and DHA reduced ICAM-1 expression (15–35%) at 12.5, 25 and/or 50 μM. VCAM-1 expression was reduced by 25 μM t10, c12 isomer and mix; omega-3 PUFA and other concentrations of CLA and TNF- α-induced E-selectin expression were unaffected. TNF α-induced inhibitor kappa B (I κB) phosphorylation was biphasic peaking at 5 min in both cell types and 60 and 120 min in HUVEC and SMC, respectively. I κB α phosphorylation and NF- κB activity was reduced (29% and 30%, respectively) by 25 μM CLA mix. n-3 PUFA did not reduce I κB α phosphorylation or NF- κB activity but reduced ADM expression. We show that n-3 PUFA and CLA reduce expression of ADM on HUVEC and vSMC. This reflected reduced adherence of monocytes to HUVEC previously reported by our group. Reduction of ICAM-1 and VCAM-1 protein expression by n-3 PUFA was less dependent on the NF- κB pathway than reduction by CLA which reflected the parallel attenuation of NF- κB activity. This indicated involvement of other transcription factors (i.e. AP-1) in the FA regulation of ADM expression and has, to our knowledge, not been previously reported.

Comparative effects of quercetin and its predominant human metabolites on adhesion molecule expression in activated human vascular endothelial cells

Adhesion of circulating monocytes to vascular endothelial cells, a critical step in both inflammation and atherosclerosis, is mediated by cross-linkage of adhesion molecules expressed on the surface of both cell types. Dietary flavonoids have been shown to have anti-inflammatory properties, decreasing the expression of cell adhesion molecules, such as vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) on endothelial cells. However, flavonoids are efficiently metabolised during absorption and the forms reaching the systemic circulation are glucuronidated, sulphated and methylated. Most previous in vitro studies of the effects of flavonoids have used the parent compounds at concentrations far higher than those physiologically achievable. We investigated the ability of quercetin and its human metabolites, at physiological concentrations (2 μmol/L and 10 μmol/L), to attenuate the inflammation-induced upregulated expression of VCAM-1, ICAM-1 and of the chemokine, monocyte chemoattractant protein-1 (MCP-1), in human umbilical vein endothelial cells (HUVECs), at the protein and transcript levels. Quercetin treatment reduced the inflammation-induced over-expression of VCAM-1 and ICAM-1 (protein and transcript) in HUVECs. Quercetin also inhibited MCP-1 gene expression. However, quercetin 3′-sulfate, quercetin 3-glucuronide and 3′-methylquercetin 3-glucuronide (isorhamnetin 3-glucuronide) generally exhibited either a reduced ability to inhibit the expression of these molecules compared with the parent aglycone or had no effect. However, all three metabolites inhibited VCAM-1 cell surface expression at 2 μmol/L. These results indicate that both quercetin and its metabolites, at physiological concentrations, can inhibit the expression of key molecules involved in monocyte recruitment during the early stages of atherosclerosis.