Interleukin-18 exacerbates skin inflammation and affects microabscesses and scale formation in a mouse model of imiquimod-induced psoriasis / 中华医学杂志(英文版)

BACKGROUND@#As a potent pro-inflammatory cytokine of the interleukin (IL)-1 family, IL-18 was elevated in early active and progressive plaque-type psoriatic lesions and that serum or plasma levels of IL-18 correlated with the Psoriasis Area and Severity Index (PASI). Although results from previous studies have established that IL-18 may aggravate psoriatic inflammation, the mechanisms of this process remain unknown. In this study, IL-18 knock out (KO) mice and wild-type (WT) mice were used to investigate the effects of IL-18 within a mouse model of psoriasis.@*METHODS@#WT and IL-18 KO mice were divided into four groups, including imiquimod (IMQ)-treated IL-18 KO group (n = 11) and WT group (n = 13) as well as their respectively gene-matched control mice (receiving vaseline; n = 12). PASI scores were used to evaluate psoriatic lesions in IMQ-treated mice. Pathological features and dermal cellular infiltration were investigated by hematoxylin and eosin staining. The levels of psoriasis-related cytokines including IL-23, IL-17, IL-12, IL-1β, IFNγ, IL-15, IL-27, and IL-4 were tested by real-time polymerase chain reaction (PCR). The protein level of IL-1β, IL-27, CXCL1, and Ly6 g were investigated by immunohistochemistry (IHC).@*RESULTS@#Acanthosis (98.46 ± 14.12 vs. 222.68 ± 71.10 μm, P < 0.01) and dermal cell infiltration (572.25 ± 47.45 vs. 762.47 ± 59.59 cells/field, P < 0.01) were significantly milder in IMQ-induced IL-18 KO mice compared with that in WT mice. IMQ-induced IL-18 KO mice manifested larger areas of Munro microabscesses (11,467.83 ± 5112.09 vs. 4093.19 ± 2591.88 μm, P < 0.01) and scales (100,935.24 ± 41,167.77 vs. 41,604.41 ± 14,184.10 μm, P < 0.01) as compared with WT mice. In skin lesions of IL-18 KO mice, the expressions of IL-1β, IL-4, and IL-27 were all significantly upregulated but IL-17 was decreased. Histologically, strong positive signals of Ly6g were observed within the epidermis of IL-18 KO mice but expressions of CXCL1 were decreased.@*CONCLUSIONS@#IL-18 may exacerbate prominent inflammation and influence pathological features in IMQ-induced mouse model of psoriasis. IL-18 may upregulate pro-inflammatory cytokines and reduce protective cytokines, thus aggravating psoriatic inflammation. In addition, IL-18 may be involved in the formation of Munro microabscesses and scales.

Obesity-Induced Peritoneal Dissemination of Ovarian Cancer and Dominant Recruitment of Macrophages in Ascites

One-fifth of cancer deaths are associated with obesity. Because the molecular mechanisms by which obesity affects the progression of ovarian cancer (OC) are poorly understood, we investigated if obesity could promote the progression of OC cells using the postmenopausal ob/ob mouse model and peritoneal dissemination of mouse ID8 OC cells. Compared to lean mice, obese mice had earlier OC occurrence, greater metastasis throughout the peritoneal cavity, a trend toward shorter survival, and higher circulating glucose and proinflammatory chemokine CXCL1 levels. Ascites in obese mice had higher levels of macrophages (Mφ) and chemokines including CCL2, CXCL12, CXCL13, G-CSF and M-CSF. Omental tumor tissues in obese mice had more adipocytes than lean mice. Our data suggest that obesity may accelerate the peritoneal dissemination of OC through higher production of pro-inflammatory chemokines and Mφ recruitment.

Mouse Model of IL-17-Dominant Rhinitis Using Polyinosinic-Polycytidylic Acid

Interleukin (IL)-17 plays an important role in rhinitis and the level thereof correlates with the severity of disease. However, no mouse model for IL-17-dominant rhinitis has yet been developed. Our objective was to establish a mouse model of IL-17-dominant rhinitis via intranasal application of polyinosinic-polycytidylic acid (abbreviated as Poly(I:C)). Mice were divided into 6 groups (n=8 for each group); 1) 1 negative control group, 2) 1 positive control group (OVA/alum model), 3) 2 Poly(I:C) groups (10 or 100 µg), and 4) 2 OVA/Poly(I:C) groups (10 or 100 µg). The positive control group was treated with the conventional OVA/alum protocol. In the Poly(I:C) and OVA/Poly(I:C) groups, phosphate-buffered saline or an OVA solution plus Poly(I:C) were administered. The OVA/Poly(I:C) groups exhibited significantly greater neutrophil infiltration and increased IL-17/interferon γ expression compared with the other groups. However, the levels of total immunoglobulin E (IgE), OVA-specific IgE, eosinophil infiltration, IL-4, IL-5, IL-6, and IL-10 were significantly lower in the OVA/Poly(I:C) groups than in mice subjected to conventional Th2-dominant OVA/alum treatment (the positive control group). IL-17 and neutrophil measurement, chemokine (C-X-C motif) ligand 1 immunohistochemistry, and confocal microscopy revealed increased numbers of IL-17-secreting cells in the nasal mucosa of the OVA/Poly(I:C) groups, which included natural killer cells, CD4 T cells, and neutrophils. In conclusion, we developed a mouse model of IL-17-dominant rhinitis using OVA together with Poly(I:C). This model will be useful in research on neutrophil- or IL-17-dominant rhinitis.

Sex differences on solid organ histological characteristics after brain death1

PURPOSE: To investigate gender differences in the evolution of the inflammatory process in rats subjected to brain death (BD). METHODS: Adult Wistar rats were divided into three groups: female; ovariectomized female; and male rats. BD was induced using intracranial balloon inflation and confirmed by maximal pupil dilatation, apnea, absence of reflex, and drop of mean arterial pressure. Six hours after BD, histological evaluation was performed in lungs, heart, liver and kidneys, and levels of inflammatory proteins, estrogen, progesterone, and corticosterone were determined in plasma. RESULTS: In the lungs, females presented more leukocyte infiltration compared to males (p<0.01). Ovariectomized female rat lungs were more hemorrhagic compared to other groups (p<0.001). In the heart, females had higher leukocyte infiltration and tissue edema compared to males (p<0.05). In the liver and kidneys, there were no differences among groups. In female group estradiol and progesterone were sharply reduced 6 hours after BD (p<0.001) to values observed in ovariectomized females and males. Corticosterone levels were similar. CONCLUSIONS: Sex hormones influence the development of inflammation and the status of organs. The increased inflammation in lungs and heart of female rats might be associated with the acute reduction in female hormones triggered by BD.

Ischemic preconditioning modifies mortality and inflammatory response

PURPOSE: To evaluate the effect of ischemic preconditioning on mortality, inflammatory mediators and oxidative stress after intestinal ischemia and reperfusion. METHODS: Male Wistar rats were allocated according to the period of ischemia with or without ischemic preconditioning which consist on clamping the superior mesenteric artery for 10 minutes followed by reperfusion for 10 minutes before the sustained ischemia period. Mortality was assessed in Phase 1 study, and the CINC-1, CINC-2 and MDA levels in the lungs were analyzed in Phase 2. RESULTS: Mortality was lower in the ischemic preconditioning group subjected to 90 minutes of ischemia compared to the group without ischemic preconditioning (I-90: 50% and IPC-90: 15%, p=0.018), and it was lower in the ischemic preconditioning group as a whole compared to the groups without ischemic preconditioning (IPC-14% and I=30%, p=0.006). Lower levels of MDA, CINC-1, and CINC-2 were observed in the animals that were subjected to ischemic preconditioning compared to the animals that were not (MDA: I-45=1.23 nmol/mg protein, and IPC-45=0.62 nmol/mg protein, p=0.0333; CINC-1: I-45=0.82 ng/mL and IPC-45=0.67 ng/mL, p=0.041; CINC-2: I-45=0.52 ng/mL and IPC-45=0.35 ng/mL, p=0.032). CONCLUSION: Ischemic preconditioning reduces mortality, inflammatory process and oxidative stress in rats subjected to intestinal ischemia and reperfusion.

JNK in spinal cord facilitates bone cancer pain in rats through modulation of CXCL1 / 华中科技大学学报（医学）（英德文版）

In patients with advanced cancer, cancer-induced bone pain (CIBP) is a severe and common problem that is difficult to manage and explain. As c-Jun N-terminal kinase (JNK) and chemokine (C-X-C motif) ligand 1 (CXCL1) have been shown to participate in several chronic pain processes, we investigated the role of JNK and CXCL1 in CIBP and the relationship between them. A rat bone cancer pain model was established by intramedullary injection of Walker 256 rat gland mammary carcinoma cells into the left tibia of Sprague-Dawley rats. As a result, intramedullary injection of Walker 256 carcinoma cells induced significant bone destruction and persistent pain. Both phosphorylated JNK1 (pJNK1) and pJNK2 showed time-dependent increases in the ipsilateral spinal cord from day 7 to day 18 after tumor injection. Inhibition of JNK activation by intrathecal administration of SP600125, a selective pJNK inhibitor, attenuated mechanical allodynia and heat hyperalgesia caused by tumor inoculation. Tumor cell inoculation also induced robust CXCL1 upregulation in the ipsilateral spinal cord on day 18 after tumor injection. Inhibition of CXCL1 by intrathecal administration of CXCL1 neutralizing antibody showed a stable analgesic effect. Intrathecal administration of SP600125 reduced CXCL1 increase in the spinal cord, whereas inhibition of CXCL1 in the spinal cord showed no influence on JNK activation. Taken together, these results suggested that JNK activation in spinal cord contributed to the maintenance of CIBP, which may act through modulation of CXCL1. Inhibition of the pJNK/CXCL1 pathway may provide a new choice for treatment of CIBP.

Chemokine (C-X-C Motif) Ligand 1 (CXCL1) Expression in the Minor Salivary Glands of Sjögren's Syndrome Patients

OBJECTIVE: To evaluate the laboratory and clinical manifestations of Sjögren's syndrome (SS) association with chemokine (C-X-C motif) ligand 1 (CXCL1) expression in the ductal and acinar salivary gland epithelial cells (SGEC) of the minor salivary glands. METHODS: The sociodemographic data of 106 SS patients was obtained, and the glandular and extraglandular manifestations of the disease documented. The minor salivary glands were biopsied and the laboratory findings analyzed. European League Against Rheumatism SS disease activity index (ESSDAI) and SS disease damage index (SSDDI) scores were obtained during biopsy. An immunohistochemical approach was used to define the expression of CXCL1 in the salivary glands. RESULTS: Of 106 patients, the minor salivary glands of 22 patients (20.7%) stained positively for CXCL1. Such CXCL1-positive patients exhibited higher ESSDAI scores at the time of biopsy than the CXCL1-negative patients (3.86±2.27 vs. 2.64±1.62, p=0.015). Lymphadenopathy was more frequently observed in CXCL1-positive patients, compared with CXCL1-negative patients (31.8% vs. 9.5%, p=0.014). No differences between groups were identified in terms of sociodemographic characteristics, laboratory data, or the extent of the glandular manifestation of SS. CONCLUSION: The expression of CXCL1 within the ductal and acinar SGEC of SS patients is associated with lymphadenopathy and elevated clinical disease activity. CXCL1 may play an important role in the disease activity and prognosis of SS.

15-deoxy-Δ¹²,¹⁴-prostaglandin J₂ ameliorates endotoxin-induced acute lung injury in rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>A proinflammatory milieu emerging in the lung due to neutrophil accumulation and activation is a key in the pathogenesis of acute lung injury (ALI). 15-deoxy-Δ(12, 14)-prostaglandin J2 (15d-PGJ2), one of the terminal products of the cyclooxygenase-2 pathway, is known to be the endogenous ligand of peroxisome proliferator-activated receptor γ (PPAR-γ) with multiple physiological properties. Growing evidence indicates that 15d-PGJ2 has anti-inflammatory, antiproliferative, cytoprotective and pro-resolving effects. We investigated whether 15d-PGJ2 has a protective effect against endotoxin-induced acute lung injury in rats.</p><p><b>METHODS</b>Twenty-four male Wistar rats were randomly assigned into four groups (n = 6 per group): sham+vehicle group, sham+15d-PGJ2 group, LPS+vehicle group, and LPS+15d-PGJ2 group. The rats were given either lipopolysaccharide (LPS, 6 mg/kg intravenously) or saline, and pretreated with 15d-PGJ2 (0.3 mg/kg intravenously) or its vehicle (dimethyl sulphoxide) 30 minutes before LPS. Histological alterations, wet/dry weight (W/D) ratio and myeloperoxidase (MPO) activity as well as tumor necrosis factor (TNF)-α and cytokine-induced neutrophil chemoattractant-1 (CINC-1) levels were determined in lung tissues four hours after LPS injection. Immunohistochemical analysis for intercellular adhesion molecule-1 (ICAM-1) expression and Western blotting analysis for nuclear factor (NF)-κB p65 translocation and IκBα protein levels were also studied.</p><p><b>RESULTS</b>15d-PGJ2 pretreatment significantly attenuated LPS-induced lung injury, and reduced the increased W/D ratio, MPO activity, TNF-α, CINC-1 levels, and ICAM-1 expression in the lung. 15d-PGJ2 also suppressed the nuclear NF-κB p65 translocation and increased cytosolic IκBα levels.</p><p><b>CONCLUSIONS</b>15d-PGJ2 protects against endotoxin-induced acute lung injury, most likely through the reduction of proinflammatory protein levels during endotoxemia subsequent to the inhibition of NF-κB activation.</p>

Effects of IL-17 on expression of GRO-α and IL-8 in fibroblasts from nasal polyps / 华中科技大学学报（医学）（英德文版）

Recent studies indicated that interleukin (IL)-17, growth-related oncogene (GRO)-α and IL-8 play an important role in the pathogenesis of nasal polyps. However, the effects of the increased amount of IL-17 and the production of GRO-α and IL-8 in human nasal polyp fibroblasts are not completely understood. This study aimed to determine the effects of the increased IL-17 on the changes of GRO-α and IL-8 expression in human nasal polyp fibroblasts and further investigate the mechanism of neutrophil infiltration in nasal polyps. Nasal polyp fibroblasts were isolated from six cases of human nasal polyps, and the cells were stimulated with five different concentrations of IL-17. Real-time fluorescence quantitative polymerase chain reaction (RT-PCR) was used to detect the mRNA expression of GRO-α and IL-8. The mRNA of GRO-α and IL-8 was expressed in unstimulated controls and remarkably increased by stimulation with IL-17. Moreover, the levels of GRO-α and IL-8 produced by fibroblasts were increased gradually with the increases in IL-17 concentrations. The present study showed that nasal fibroblasts can produce GRO-α and IL-8, and their production is remarkably enhanced by IL-17 stimulation, thereby clarifying the mechanism of the IL-17 mediated neutrophil infiltration in nasal polyps. These findings might provide a rationale for using IL-17 inhibitors as a treatment for nasal inflammatory diseases such as nasal polyps.

Differential expression of CXCL1, CXCL9 CXCL10 and CXCL12 chemokines in alopecia areata

Alopecia Areata [AA] is a non-scarring, autoimmune disorder which causes hair loss. Inflammatory reactions are involved in hair loss of the scalp and/or body. The involvement of chemokine receptors in the pathogenesis of AA is well defined among which, CXCL1 acts on neutrophils and CXCL9, CXCL10 and CXCL12 and serve as T lymphocytes recruiters. To study the serum levels of ELR+ and ELR- CXCL1, CXCL9, CXCL10 and CXCL12 in the patients suffering from AA and healthy controls. The study population of consisted of 30 patients suffering from AA and 30 healthy controls. Serum concentrations of CXCL1, CXCL9, CXCL10 and CXCL12 were measured using enzymelinked immunosorbent assay [ELISA]. Current results showed that AA patients had significantly elevated serum levels of CXCL9 and CXCL10 in comparison to controls [p<0.001]. These results also demonstrated that serum levels of CXCL1 and CXCL12 were significantly decreased in AA patients compared to control [p<0.001]. CXCL9 and CXCL10 are elevated in the AA patients and may be involved in the recruitment of T lymphocytes to the inflamed tissues. Moreover, due to the significant role played by these chemokines in angiogenesis/ angiostatis phenomenon they could be considered as useful biomarkers in AA diagnosis and therapy

Effect of CXCL1 gene expression on the biological function of epithelial ovarian carcinoma cells in vitro / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the effect of CXCL1 gene expression on biological function of ovarian cancer cells and its mechanism of action.</p><p><b>METHODS</b>RT-PCR was used to amplify the full-length sequence of CXCL1, which was used to construct the recombinant lentiviral plasmids, and then the plasmids were packaged with human renal epithelial cell line 293T cells, and the ovarian cancer 2780 cells were transfected with CXCL1 gene by virus supernatant particles. The expression of CXCL1 mRNA and protein in 2780 cells with lentivirus-mediated CXCL1expression were determined by RT-PCR and ELISA, respectively. The growth curve, cell cycle and colony formation in vitro were measured by MTT assay, flow cytometry and colony formation counting, respectively. The cell invasion and migration in vitro was detected by Transwell chambers and migration attack methods, respectively.</p><p><b>RESULTS</b>The sequencing results showed that the recombinant lentiviral plasmid of CXCL1-pWPI had 100% homology with the CXCL1 gene, identified by BLAST analysis. RT-PCR and ELISA results showed positive expression of CXCL1 mRNA and protein in the CXCL1-PWPI group. The doubling time of the CXCL1-PWPI group was significantly shorter than that in the A2780 and PWPI groups (P < 0.05). The rate of colony-formation in the CXCL1-PWPI group was also significantly higher than that of the A2780 and PWPI groups (P < 0.05). The proportion of cells in G1 phase (44.0%) in the CXCL1-PWPI group was also significantly lower compared with that in the PWPI and A2780 groups (61.4% and 62.7%), with a significant difference (P < 0.001). There was no significant difference between the cell migration capacity (P > 0.05) of the CXCL1-PWPI, PWPI and A2780 groups, but the invasion capacity of the CXCL1-PWPI group was significantly higher than that of the PWPI and A2780 groups (P < 0.05).</p><p><b>CONCLUSION</b>The over-expression of CXCL1 gene may promote the proliferation and invasion ability of A2780 cells in vitro.</p>

Evaluation of the effects of ozone therapy in the treatment of intra-abdominal infection in rats

INTRODUCTION: The antibacterial effect of ozone (O3) has been described in the extant literature, but the role of O3 therapy in the treatment of certain types of infection remains controversial. OBJECTIVES: To evaluate the effect of intraperitoneal (i.p.) O3 application in a cecal ligation/puncture rat model on interleukins (IL-6, IL-10) and cytokine-induced neutrophil chemoattractant (CINC)-1 serum levels, acute lung injury and survival rates. METHODS: Four animal groups were used for the study: a) the SHAM group underwent laparotomy; b) the cecal ligation/puncture group underwent cecal ligation/puncture procedures; and c) the CLP+O2 and CLP+O3 groups underwent CLP+ corresponding gas mixture infusions (i.p.) throughout the observation period. IL-6, CINC-1 and IL-10 concentrations were determined by enzyme-linked immunosorbent assay (ELISA). Acute lung injury was evaluated with the Evans blue dye lung leakage method and by lung histology. P<0.05 was considered significant. RESULTS: CINC-1 was at the lowest level in the SHAM group and was lower for the CLP+O3 group vs. the CLP+O2 group and the cecal ligation/puncture group. IL-10 was lower for the SHAM group vs. the other three groups, which were similar compared to each other. IL-6 was lower for the SHAM group vs. all other groups, was lower for the CLP+O3 or CLP+O2 group vs. the cecal ligation/puncture group, and was similar for the CLP+O3 group vs. the CLP+O2 group. The lung histology score was lower for the SHAM group vs. the other groups. The Evans blue dye result was lower for the CLP+O3 group vs. the CLP+O2 group and the cecal ligation/puncture group but similar to that of the SHAM group. The survival rate for the CLP+O3 group was lower than for the SHAM group and similar to that for the other 2 groups (CLP and CLP+O2). CONCLUSION: Ozone therapy modulated the inflammatory response and acute lung injury in the cecal ligation/puncture infection model in rats, although there was no ...

Circulatory neutrophil chemokines in statin-treated diabetic patients

To assess the effect of statins on the circulatory levels of neutrophil chemokines, namely, granulocyte chemotactic protein-2 [GCP-2], growth regulated oncogene-alpha [GRO-alpha] and epithelial-cell-derived neutrophil-activating peptide-78 [ENA-78] in patients with diabetes. We studied 91 diabetic patients [46 were statin-treated and 45 were not] and 28 healthy subjects. We measured the levels of GCP-2, GRO-alpha, and ENA-78 in the serum for the 3 groups using an enzyme linked immunosorbent assay. This cross-sectional study was conducted at King Khalid University Hospital [KKUH], Riyadh, Kingdom of Saudi Arabia, from January 2006 to July 2007. Circulating levels of GCP-2, ENA-78, and not GRO-alpha, were significantly higher in diabetic patients as compared to healthy subjects [p<0.05]. Statins dropped the levels of both GCP-2 and GRO-alpha. The ENA-78 levels were not affected by statin therapy. There was no correlation between the levels of these chemokines with the body mass index and glycemia in the population studied. Diabetes is associated with an elevation of GCP-2 and ENA-78, and not GRO-alpha. Statins have a significant role in reducing the level of GCP-2

Role of early growth response factor-1 signal pathway in acute intrahepatic cholestatic hepatic injury in rats / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To explore the role of early growth response factor-1 (Egr-1) signal pathway in acute intrahepatic cholestatic liver injury in rats.</p><p><b>METHODS</b>A single dose (50 mg/kg) of alpha-naphthylisothiocyanate (ANIT) was administered by gavage to each experimental rat to induce intrahepatic cholestasis. Liver tissue and serum specimens were collected from rats at 24, 48 and 72 h after the intoxication. The values of Egr-1, cytokine induced neutrophil chemoattractant 1(CINC-1), macrophage inflammatory protein-2 (MIP-2) mRNA, the protein expression of inducible nitricoxide synthase (iNOS) and the values of tumor necrosis factor alpha (TNF alpha) and interleukin 6 (IL-6) were assayed by real-time PCR, immunohistochemistry, and ELISA, respectively. The levels of MDA, SOD, NO and MPO were assayed by thiobarbituric acid method, xanthine oxidase method, nitric acid deoxidizing assay, and colorimetric method, respectively.</p><p><b>RESULTS</b>In the model group at 24, 48, 72 h after intoxication, the values of CINC-1 and MIP-2 mRNA were higher than those of the controls (P < 0.05). In the model group at 24, 48 h after intoxication, the value of Egr-1 mRNA was higher than that of the controls (P < 0.05), but there was no significant difference at 72 h (P < 0.05). Of the model group, the absorbance value of iNOS was lower than that of the controls at 24, 48 and 72 h (P < 0.05). Of the model group at 24, 48, 72 h after intoxication, the values of TNF alpha, IL-6, MPO and MDA were higher than those of the controls (P < 0.05), but the values of NO and SOD were lower than those of the controls (P < 0.05).</p><p><b>CONCLUSIONS</b>Egr-1 signal pathway is involved in acute intrahepatic cholestatic liver injury induced by ANIT. After Egr-1 was activated, CINC-1 and MIP-2 are activated consequently and attract neutrophils into the liver. TNF alpha and IL-6 are activated at the same time, so neutrophils are activated and the resulting lipid peroxidation and MDA increased, injuring the liver. iNOS and NO may play a protective role in acute intrahepatic cholestatic liver injury induced by ANIT.</p>

Activation of nuclear factor-kappaB signaling pathway in rat gastric mucosa during stress ulceration / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the time course of nuclear factor-kappaB (NF-kappaB) activation in the process of stress ulcer formation.</p><p><b>METHODS</b>Model of stress ulcer was reproduced by subjecting male Sprague-Dawley rats to water-immersion restraint (WIR) stress. At indicated time after the beginning of WIR stress, animals were sacrificed and cytoplasmic and nuclear protein and total RNA were prepared from gastric corpus mucosal tissues. DNA-binding activity of NF-KB was assessed as an index of NF-kappaB activation with electrophoretic mobility shift assay. Degradation of IkappaBalpha and IkappaBbeta, the inhibitory proteins of NF-kappaB, was analyzed by Western blot analysis. Expression of NF-kappaB dependent genes including tumor necrosis factor-alpha (TNF-alpha) , interleukin-1beta (IL-1beta), cytokine-inducible neutrophil chemoattractant-1 ( CINC-1), intercellular adhesion molecule-1 (ICAM-1), and inducible nitric oxide synthase (iNOS) was detected with Northern blot analysis.</p><p><b>RESULTS</b>WIR stress induced a rapid biphasic activation of gastric mucosal NF-kappaB within 15 min of the beginning of stress, peaking at 45 min and 360 min. Compared with baseline, NF-kappaB activation by stress was increased (10.6 +/- 1.3) and (8.9 +/- 1.2) fold at 45 min and 360 min, respectively (P < 0.01). Antibody supershift assays revealed that p50/p65 heterodimer was the major active component of mucosal NF-kappaB. Western blot analysis showed that degradation of IkappaBalpha and IkappaBbeta occurred at first and second wave of NF-kappaB activation. Corresponding with the rapid and persistent activation of NF-kappaB, the levels of TNF-alpha, IL-1beta, CINC-1 and ICAM-1 mRNA in gastric mucosa were markedly increased 15 to 30 min after stress, respectively. Up-regulation of iNOS mRNAs was observed 30 to 90 min after stress, and the expression of all of these genes was increased consistently until the end of stress.</p><p><b>CONCLUSION</b>NF-kappaB activation is an early event and may play an important role in proinflammatory gene over-expression in rat gastric mucosa during WIR stress.</p>