Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:2.6.1.2 (alanine aminotransferase)
26,722 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Intercellular adhesion molecule-1, an immunoglobulin supergene family member, is known to account for important steps in cell activation and the immune response. By a non-isotopic slot-dot immunoblotting assay, we measured circulating levels of intercellular adhesion molecule-1 in 26 patients with hepatitis C virus-associated chronic active liver disease before and after beta-interferon therapy, in 6 patients with non-A, non-B acute self-limiting hepatitis and in 13 healthy subjects. Circulating intercellular adhesion molecule-1 was found in 10 of 13 (77%) normal controls at low concentrations which were not statistically different from those measured in patients with hepatitis C virus-associated chronic active liver disease responsive to beta-interferon, whereas significantly higher levels were found in unresponsive patients. Higher serum intercellular adhesion molecule-1 levels were found in 4 of 10 (40%) beta-interferon-responsive patients compared with 13 of 16 (18%) unresponsive patients. Intercellular adhesion molecule-1 levels persisted after discontinuation of beta-interferon treatment and did not correlate with hepatocytolysis (as indicated by alanine aminotransferase serum activity) either in chronic active liver disease or acute hepatitis. However, a good correlation was found between intercellular adhesion molecule-1 and its expression on liver cells, thus emphasizing that induced circulating levels may reflect the state of activation at the sites of the inflammatory process. These data strongly support the view that intercellular adhesion molecule-1 plays an important role in liver cell damage in hepatitis C virus-associated acute and chronic liver disease, and that its circulating levels may be a good prognostic parameter of responsiveness to beta-interferon therapy.
...
PMID:Circulating levels and liver tissue distribution of intercellular adhesion molecule-1 during beta-interferon therapy of hepatitis C virus-associated chronic active liver disease. 135 8

The potential role of intercellular adhesion molecule-1 (ICAM-1) in the pathogenesis of reperfusion injury was investigated in male Fischer rats subjected to 45 min of hepatic ischemia and 24 h of reperfusion. ICAM-1 mRNA levels increased during ischemia in the ischemic liver lobes; however, during reperfusion mRNA levels increased in both the ischemic and nonischemic lobes. Immunohistochemical evaluation indicated ICAM-1 expression only on sinusoidal lining cells in controls; ischemia-reperfusion enhanced ICAM-1 expression in the sinusoids and induced some expression on hepatocytes. The monoclonal anti-ICAM-1 antibody 1A29, but not an immunoglobulin G control antibody, administered at 1 h and 8 h of reperfusion (2 mg/kg) significantly attenuated liver injury as indicated by 51% lower plasma alanine aminotransferase activities and 32-36% less hepatic necrosis at 24 h without affecting reactive oxygen formation by Kupffer cells and hepatic neutrophils. Although 1A29 reduced neutrophil extravasation in a glycogen peritonitis by 60%, the antibody had no significant effect on hepatic neutrophil infiltration during reperfusion. These data suggest that ICAM-1 plays a significant role during the neutrophil-dependent injury phase after hepatic ischemia and reperfusion and therefore blocking this adhesion molecule may have therapeutic potential against postischemic acute liver failure.
...
PMID:Intercellular adhesion molecule 1 (ICAM-1) expression and its role in neutrophil-induced ischemia-reperfusion injury in rat liver. 788 6

The expression of intercellular adhesion molecule-1 (ICAM-1) on the hepatocyte membrane was studied in 27 patients with chronic hepatitis B and C (CHB, CHC) by immunostaining using a monoclonal antibody. ICAM-1 was expressed focally in a honeycomb-like pattern by hepatocytes in livers of 26/27 patients. The degree of ICAM-1 expression was closely related to the ALT level and the histological grade of liver damage. Abundant cytotoxic T cells (CD8+, CD11b-) were found in ICAM-1-positive areas of the liver. Zones of focal necrosis contained both ICAM-1-positive hepatocytes and cytotoxic T cells. The expression of ICAM-1 was decreased in 4/6 CHB patients after interferon-alpha therapy. No relationship between the degree of hepatocyte ICAM-1 expression and viral replication markers (DNA polymerase activity and the presence of HBcA in the liver) was observed in patients with CHB. In addition, no positive correlation was found between the distribution of ICAM-1-positive hepatocytes and HBcAg-positive hepatocytes. These results suggest that ICAM-1 may play an important role in the pathogenesis of hepatocellular injury mediated by cytotoxic T cells in CHB and CHC.
...
PMID:Intercellular adhesion molecule-1 expression on the hepatocyte membrane of patients with chronic hepatitis B and C. 809 55

Soluble intercellular adhesion molecule-1(ICAM-1) is probably released from a variety of cells, including leukocytes and endothelial cells at sites of inflammation or in the circulation, and serum levels may therefore be used to give an indication of immune activation and inflammatory processes. In the present study, an ELISA was used to measure serum ICAM-1 levels in forty patients with endemic chronic liver diseases and these were correlated with histological changes in the liver and with liver functions. Serum ICAM-1 levels were significantly higher in patients with chronic active liver diseases than in normal subjects and correlated positively with the grade of histological activity. Furthermore, serum levels of ICAM-1 were substantially greater in patients with cirrhosis than in those without cirrhosis. There was also a significant positive correlation between serum levels of ICAM-1 and serum alanine aminotransferase activities. It is concluded that, in chronic liver disease, intercellular adhesion molecule-1 serum concentration seems to represent hepatocellular damage. The authors suggest that serum ICAM-1 may prove worthy in the investigation, diagnosis and therapeutic monitoring of various inflammatory conditions of the liver.
...
PMID:Circulating intercellular adhesion molecule-1 in endemic chronic liver diseases. 909 39

Serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) have been examined in 38 patients with chronic hepatitis C liver disease treated with interferon. The sICAM-1 values were found to correlate significantly with the ALT values. Pre-treatment sICAM-1 values of responder and nonresponder patients were not significantly different while, by the end of the treatment, the values of responders were significantly lower compared to those of nonresponders. However, no difference could be found between sustained and relapse responders. Of the 21 patients examined for PBMC HCV-RNA, 15 (71.4%) were found to be positive. Neither the rate of responsivity to interferon treatment, nor the mean sICAM-1 values correlated with the positivity of PBMC HCV-RNA. However, the clearance of serum and PBMC HCV-RNA was associated to a significant decrease of sICAM-1 and ALT levels. In conclusion, sICAM-1 values were found to correlate with ongoing viral replication and liver cytonecrosis, but were not influenced by the concomitant HCV infection of PBMC.
...
PMID:HCV infection of peripheral blood mono nuclear cells and serum levels of soluble ICAM-1 in patients treated with interferon. 934 1

Tumor necrosis factor (TNF) is released during hepatic ischemia/reperfusion (I/R) and plays an important role in the ensuing neutrophil-mediated lung and liver injury. Since TNF is not a direct neutrophil chemotaxin, we hypothesized that TNF may up-regulate neutrophil adhesion molecules, specifically intercellular adhesion molecule-1 (ICAM-1), following hepatic I/R, and that this molecule then plays an important role in tissue neutrophil influx. Rats underwent 90 min of lobar hepatic ischemia with reperfusion. Pulmonary and hepatic ICAM-1 expression were assessed by reverse transcription-polymerase chain reaction, Western blot analysis, and immunohistochemical staining. Increases in hepatic ICAM-1 were demonstrated within 1 h of reperfusion, while increases in pulmonary ICAM-1 were not seen until 6 h of reperfusion. Next, rats were treated with anti-TNF antibody or control antibody without TNF neutralizing properties prior to hepatic I/R. Pretreatment with anti-TNF antibody significantly decreased pulmonary and hepatic ICAM-1 expression after hepatic I/R. We next investigated the effects of pretreatment with anti-ICAM-1 antibodies on the lung and liver injury that follows hepatic I/R. Lung injury was assessed by changes in pulmonary capillary permeability as estimated by extravasation of Evans Blue dye and pulmonary neutrophil influx as measured by lung myeloperoxidase levels. Liver injury was assessed by hepatic neutrophil morphometrics and plasma liver enzymes (alanine aminotransferase). Pretreatment with anti-ICAM-1 antibodies significantly decreased pulmonary capillary permeability, pulmonary myeloperoxidase, hepatic neutrophil influx, and plasma alanine aminotransferase, as compared to animals pretreated with control antibody. These data suggest that TNF is a proximal trigger for pulmonary and hepatic ICAM-1 up-regulation following hepatic ischemia with reperfusion, and that ICAM-1 is important for pulmonary and hepatic neutrophil influx, with the resultant tissue injury, following hepatic I/R.
...
PMID:Tumor necrosis factor up-regulates intercellular adhesion molecule 1, which is important in the neutrophil-dependent lung and liver injury associated with hepatic ischemia and reperfusion in the rat. 974 46

In the present study, we examined the effects of peroxynitrite on reperfusion injury using a rat model of hepatic ischemia-reperfusion (HI/R). The left and median lobes of the liver were subjected to 30 min of ischemia, followed by 4 h of reperfusion. Groups A and B rats were sham-operated controls that received vehicle or peroxynitrite; groups C and D rats were subjected to HI/R and received peroxynitrite or vehicle, respectively. A dose of 2 micromol/kg body wt of peroxynitrite, diluted in saline (pH 9.0, 4 degrees C), was administered as a bolus through a portal vein catheter at 0, 60, and 120 min after reperfusion. Results showed that superoxide generation in the ischemic lobes of the liver and plasma alanine aminotransferase (ALT) activity of group C were decreased by 43% and 45%, respectively, compared with group D. Leukocyte accumulations in the ischemic lobes of liver and circulating leukocytes were decreased by 40% and 27%, respectively, in group C vs. D. The ratios of mRNA of P-selectin and intercellular adhesion molecule-1 (ICAM-1) to glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA extracted from the ischemic lobes of the liver of group C were decreased compared with group D. There were no differences between the groups A and B in terms of plasma ALT activity, circulating leukocytes, superoxide generation, and leukocyte infiltration in the ischemic lobes of the liver. Moreover, hemodynamic parameters (i.e., mean arterial blood pressure, cardiac index, stroke index, and systemic vascular resistance) were not significantly different among groups B, C, and D. These results suggest that administration of peroxynitrite via the portal vein only has a local effect. Exogenous peroxynitrite at physiological concentrations attenuates leukocyte-endothelial interaction and reduces leukocyte infiltration. The mechanism of the reduction of leukocyte infiltration into ischemic lobes of the liver appears because of decreased expression of mRNA of P-selectin and ICAM-1. The net effect of administration of peroxynitrite may be to reduce adhesion molecule-mediated, leukocyte-dependent reperfusion injury.
...
PMID:Peroxynitrite attenuates hepatic ischemia-reperfusion injury. 1107 13

The overall objective of this study was to determine whether genetically induced hypercholesterolemia alters the inflammatory and microvascular responses of mouse liver to ischemia-reperfusion (I/R). The accumulation of rhodamine 6G-labeled leukocytes and the number of nonperfused sinusoids (NPS) were monitored (by intravital microscopy) in the liver of wild-type (WT) and low-density lipoprotein receptor-deficient (LDLr(-/-)) mice for 1 h after a 30-min period of normothermic ischemia. Plasma alanine transaminase (ALT) levels were used to monitor hepatocellular injury. Microvascular leukostasis as well as increases in NPS and plasma ALT were observed at 60 min after hepatic I/R in both WT and in LDLr(-/-) mice; however, these responses were greatly exaggerated in LDLr(-/-) mice. Pretreatment of LDLr(-/-) mice with gadolinium chloride, which reduces Kupffer cell function, attenuated the hepatic leukostasis, NPS, and hepatocellular injury elicited by I/R. Similar protection against I/R was observed in LDLr(-/-) mice pretreated with antibodies directed against tumor necrosis factor-alpha, intercellular adhesion molecule-1 (ICAM-1), or P-selectin. These findings indicate that chronic hypercholesterolemia predisposes the hepatic microvasculature to the deleterious effects of I/R. Kupffer cell activation and the leukocyte adhesion receptors ICAM-1 and P-selectin appear to contribute to the exaggerated inflammatory responses observed in the postischemic liver of LDLr(-/-) mice.
...
PMID:Hepatic microvascular responses to ischemia-reperfusion in low-density lipoprotein receptor knockout mice. 1109 49

Host immunomodulation through T cell action may play a pivotal role in determining the response to interferon (IFN) therapy for chronic hepatitis C. We examined whether the early changes in the host immune response were helpful in predicting the final effect in 31 patients with chronic hepatitis C receiving IFN. IFN treatment significantly reduced the serum levels of intercellular adhesion molecule-1 (ICAM-1) and E-selectin, and significantly increased those of vascular cell adhesion molecule-1 (VCAM-1) and interleukin-2 receptor alpha (IL-2Ralpha) in the first 7-10 days. Serum levels of these immunological parameters did not correlate with serum alanine aminotransferase (ALT) when evaluated with either absolute values or relative values (over pre-treatment value), implying that our results are not just secondary to improvement in hepatic inflammation. The relative changes (Delta) in these parameters reflected the long-term response to IFN therapy, i.e. the lower the change, the more effective the therapy was. Among these serum parameters, DeltaIL-2Ralpha within the first 7-10 days of IFN treatment was the most useful parameter in predicting the response to therapy. In conclusion, a dynamic immunomodulation during the early phase of IFN therapy may determine the subsequent long-term response to IFN therapy.
...
PMID:Change of the host immune response during the early phase of interferon therapy correlates with its long-term efficacy for chronic hepatitis C. 1116 38

PNA+Tempol, albumin containing conjugated (polynitroxyl albumin; PNA) and free (4-hydroxyl-2,2,6,6-tetramethyl-piperidinyl-1-oxyl; Tempol) nitroxide may protect against injury caused by reactive oxygen species. Therefore, the actions of PNA+Tempol on liver injury and inflammation induced by hepatic ischemia and reperfusion (I/R) were examined. Rats were subjected to 1 h ischemia followed by 24 h reperfusion in the absence (I/R) or presence of PNA+Tempol (25%; 15 mL/kg, i.v.) (I/R+PNA+Tempol) or human serum albumin (23%; 13.5 mL/kg, i.v.) (I/R+HSA). Test solutions were administered prior to and for 2 h during reperfusion. Sham-operated rats underwent surgery with neither ischemia nor infusion. I/R+PNA+Tempol rats had significantly less liver injury and inflammation than I/R rats. I/R+PNA+Tempol livers exhibited focal lesions whereas I/R livers exhibited global necrosis. Likewise, plasma ALT activity was significantly lower in I/R+PNA+Tempol rats. PNA+Tempol reduced I/R-induced neutrophil accumulation and intercellular adhesion molecule-1 (ICAM-1) expression. HSA did not alter I/R-induced liver injury or inflammation. Sham-operated rats exhibited normal liver morphology and no inflammation. Attenuation of I/R liver injury by PNA+Tempol may be mediated by its effect on inflammation, the major contributor to I/R injury. Reduction of inflammation by PNA+Tempol is most likely due to the antioxidative nature of the nitroxides.
...
PMID:Polynitroxyl albumin plus tempol attenuates liver injury and inflammation after hepatic ischemia and reperfusion. 1119 30


1 2 3 4 Next >>

---