Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bio-Catalyzer alpha . rho No. 11 (Bio-Normalizer), a natural health food product prepared by yeast fermentation of medicinal plants, has been recently reported to possess antioxidant properties. To better define its antioxidant action, we investigated the effects of orally supplemented Bio-Normalizer on oxidative damage in the rat heart. Hearts were isolated from control or Bio-Normalizer supplemented animals and 1) exposed to ischemia-reperfusion using the Langendorff technique, or 2) homogenized and exposed to peroxyl radicals generated from (2,2'-azobis (2,4'-dimethylvaleronitrile) (AMVN). During reperfusion following 40 minutes of ischemia, leakage of lactate dehydrogenase from hearts isolated from Bio-Normalizer supplemented rats was significantly lower than from hearts of control animals. Furthermore, lower levels of AMVN-induced accumulation of thiobarbituric acid reactive substances and of protein carbonyl derivatives were measured in homogenates prepared from hearts isolated from Bio-Normalizer supplemented rats than in samples from control animals. Our findings confirm an antioxidant action of Bio-Normalizer and show that it protects the heart against ischemia-reperfusion induced damage.
Biochem Mol Biol Int 1995 Aug
PMID:Bio-Catalyzer alpha . rho No. 11 (Bio-Normalizer) supplementation: effect on oxidative stress to isolated rat hearts. 853 98

Complement activation has been implicated in the pathogenesis of several human diseases. Recently, a monoclonal antibody, (N19-8) that recognizes the human complement protein C5 has been shown to effectively block the cleavage of C5 into C5a and C5b, thereby blocking terminal complement activation. In this study, a recombinant N19-8 scFv antibody fragment was constructed from the N19-8 variable regions, and produced in both mammalian and bacterial cells. The N19-8 scFv bound human C5 and was as potent as the N19-8 monoclonal antibody at inhibiting human C5b-9-mediated hemolysis of chicken erythrocytes. In contrast, the N19-8 scFv only partially retained the ability of the N19-8 monoclonal antibody to inhibit C5a generation. To investigate the ability of the N19-8 scFv to inhibit complement-mediated tissue damage, complement-dependent myocardial injury was induced in isolated mouse hearts by perfusion with Krebs-Henseleit buffer containing 6% human plasma. The perfused hearts sustained extensive deposition of human C3 and C5b-9, resulting in increased coronary artery perfusion pressure, end-diastolic pressure, and a decrease in heart rate until the hearts ceased beating approximately 10 min after addition of plasma. Hearts treated with human plasma supplemented with either the N19-8 monoclonal antibody or the N19-8 scFv did not show any detectable changes in cardiac performance for at least 1 hr following the addition of plasma. Hearts treated with human plasma alone showed extensive deposition of C3 and C5b-9, while hearts treated with human plasma containing N19-8 scFv showed extensive deposition of C3, but no detectable deposition of C5b-9. Administration of a 100 mg bolus dose of N19-8 scFv to rhesus monkeys inhibited the serum hemolytic activity by at least 50% for up to 2 hr. Pharmacokinetic analysis of N19-8 scFv serum levels suggested a two-compartment model with a T1/2 alpha of 27 min. Together, these data suggest the recombinant N19-8 scFv is a potent inhibitor of the terminal complement cascade and may have potential in vivo applications where short duration inhibition of terminal complement activity is desirable.
Mol Immunol 1995 Nov
PMID:In vitro and in vivo inhibition of complement activity by a single-chain Fv fragment recognizing human C5. 855 43

Low flow ischemia with stable hemodynamic function can result in partial metabolic recovery characterized by an increase in phosphocreatine (PCr). Prior data suggest that glycolytic production of adenosine triphosphate (ATP) may be critical for this recovery and that the ATP produced by oxidative phosphorylation alone may be insufficient. This study tested the hypotheses that, during moderate low flow ischemia, (a) metabolic recovery is dependent on glycolytic production of ATP, and, therefore, (b) a mitochondrial substrate such as pyruvate alone is inadequate to allow metabolic recovery. High energy phosphates, pH, and lactate release were measured during 2 h of moderate low flow ischemia. Hearts were perfused with either a glycolytic plus mitochondrial substrate (glucose, insulin and pyruvate) or a mitochondrial substrate alone (pyruvate). Flow reductions required to reduce PCr by approximately 8% resulted in stable and equal reductions of rate-pressure product in each group. PCr recovered fully during the ischemic period in control hearts with glycolytic substrate, associated with preservation of normal end-diastolic pressure, and increased lactate release during the first hour of ischemia. Reperfusion of these hearts restored hemodynamic function and increased PCr above baseline values. In contrast, the use of pyruvate alone as a substrate resulted in a progressive fall of PCr during ischemia, increased end-diastolic pressure, and no significant increase in lactate release. Reperfusion in these hearts restored hemodynamic function, but did not result in normalization of PCr. Both groups had significant reductions in ATP during ischemia. Recovery of PCr during ongoing moderate low flow ischemia is observed in the presence of mixed glycolytic and mitochondrial substrates (glucose, insulin and pyruvate) but is not observed with pyruvate as a sole mitochondrial substrate. These data support a critical role for glycolytic flux under these conditions, suggesting that ATP generated solely by oxidative phosphorylation is not sufficient to promote metabolic recovery or maintain diastolic function during moderate low flow ischemia.
J Mol Cell Cardiol 1995 Oct
PMID:Requirement of glycolytic substrate for metabolic recovery during moderate low flow ischemia. 857 33

In this study we investigated whether two low-molecular-weight (LMW) ligands with high affinity for copper (Cu) play a role in the transplacental transport of Cu in the rat. Dams on days 20-21 of gestation were anesthetized and injected via the femoral vein with 5 mg/kg (79 mumol/kg) Cu in 0.5 ml, as either the acetate [Cu(AcO)2], as a 1;10 mixture with L-histidine [Cu(His)10], or as the Cu-(glycyl-glycyl-L-histidine) [G-G-H] complex. Controls received saline. After laparotomy, several fetuses and their placentas were removed at 0, 10, 20, 40, and 60 min after injection, simultaneously with dam blood. Peak Cu concentration in dam plasma occurred at 10 min and was highest following Cu(AcO)2 injection. At 10 and 20 min the placentas from the Cu(AcO)2 and the Cu(G-G-H) groups had higher Cu levels than the controls. By 40 min placentas from all rats injected with Cu had similar Cu concentrations. In the Cu(AcO)2 group there was a positive correlation between dam plasma and placental Cu (r = 0.527, P < 0.05). A sharp downhill gradient was observed between dam and fetus. Fetal plasma Cu levels did not differ among all groups at any time. The data indicate that LMW ligands do not enhance overall maternal-to-fetal Cu transfer, but that an excess of His may inhibit the release of Cu from placenta to fetus.
Biochem Mol Med 1995 Oct
PMID:Placental copper transport in the rat: role of low-molecular-weight ligands. 859 40

Reduced glutathione (GSH) is a major myocardial antioxidant. Since reperfusion phenomena such as ventricular fibrillation (VF) are associated with oxygen free radical production during ischaemia, myocardial GSH depletion might be expected to increase susceptibility to such phenomena. This possibility was tested in isolated rat hearts using diethylmaleate (DEM) or L-buthionine-SR-sulfoximine (BSO) to deplete myocardial GSH. High dose DEM (860 mg/kg) depleted myocardial GSH from a control mean of 7.64 +/- 0.73 to 3.18 +/- 0.56, low dose DEM (215 mg/kg) to 4.29 +/- 0.53 nmol/mg protein and BSO (4 mmol/kg) from a control mean of 6.94 +/- 0.54 to 2.18 +/- 0.14 nmol/mg protein. Hearts were perfused in the Langendorff mode at 37 degrees C with bicarbonate buffer (K+ = 4.3 mM). Regional ischaemia was induced for 5, 8.5, 10, 20 or 40 min (DEM groups: n = 10/treatment/time point) or 8.5 min only (BSO groups: n = 10/treatment) then hearts were reperfused for 5 min. Reperfusion VF incidence showed a classical "bell-shaped" curve, but there was no difference in VF incidence, VF time-to-onset, arrhythmia duration and "arrhythmia scores" between GSH-depleted and control hearts. Depleting myocardial GSH is not proarrhythmic for reperfusion-induced arrhythmias. It would appear GSH is not significantly involved in protecting against the oxidant stress of reperfusion, or conversely that the reserve of this redox system is so high only severe depletion might show an effect.
J Mol Cell Cardiol 1996 Apr
PMID:Ventricular arrhythmias induced by ischaemia-reperfusion are unaffected by myocardial glutathione depletion. 873 96

The biochemical and cellular mechanisms involved in the development and/or maintenance of morphine tolerance remain unclear. In the adult central nervous system (CNS) results are contradictory. For the neonate, a variety of drug induced deficits have been observed following prenatal addiction to opioids, although very little work on the biochemical and molecular level has been done. Therefore, the present study was carried out to investigate the effects of prenatal morphine treatment on the levels and expression of endogenous opioid peptides in brain regions of newborns. Dams were implanted with one morphine pellet (75 mg each) 1 week prior to the birth of pups. Changes in mRNA levels for the opioid peptides were determined by Northern blot analysis. Alterations in opioid peptide levels were determined by radioimmunoassays. Prenatal morphine treatment significantly increased proenkephalin mRNA levels and decreased met-enkephalin levels in striatum of newborns. These data are in contrast to what is observed in the adult CNS. These data indicate that prenatal morphine treatment may increase met-enkephalin release and/or cause inhibition at the level of translation. In addition, increased transcription may be necessary to maintain equilibrium in the system when there is an increase in met-enkephalin release.
Brain Res Mol Brain Res 1995 Nov
PMID:Prenatal morphine exposure differentially alters expression of opioid peptides in striatum of newborns. 875 Aug 81

Following left coronary artery ligation in the rat, markedly increased angiotensin converting enzyme (ACE) binding appears at the site of myocardial infarction (MI). This is also the case in fibrosed visceral pericardium that follows pericardiotomy alone (without MI). Immunohistochemical ACE labeling, using a monoclonal antibody, indicates fibroblast-like calls express ACE at each of these sites of tissue repair. It is unknown, however, whether these cells are phenotypically transformed fibroblasts containing alpha-smooth muscle actin (i.e. myofibroblasts). This study was therefore undertaken to determine whether myofibroblasts appear at the site of MI and pericardial fibrosis and their relationship to ACE expression. MI was created by left coronary artery ligation. Fibrosis of the visceral pericardium was induced by pericardiotomy alone. Hearts were studied on postoperative day 3, week 1, 2, 4 and 8. In serial sections of the same heart: immunohistochemistry (anti alpha-smooth muscle actin antibody and monoclonal ACE antibody, 9B9) was used to detect myofibroblasts and cells expressing ACE, respectively. We found that at sites of MI and pericardial fibrosis, myofibroblasts began to appear on day 3 and became abundant at week 1, 2, 4 and remained in these repairing sites for at least 8 weeks. Myofibroblasts at sites of MI and pericardial fibrosis are positively labeled by ACE antibody. Thus in these models of tissue repair involving either MI or pericardial fibrosis, myofibroblasts are associated with ACE expression. These findings suggest that myofibroblast ACE may play a role in the fibrogenic response of tissue repair in the rat myocardium by regulating local concentrations of substances involved in healing and matrix remodeling.
J Mol Cell Cardiol 1996 May
PMID:Angiotensin converting enzyme and myofibroblasts during tissue repair in the rat heart. 876 25

To test the authors' hypothesis that cellular antioxidant enzymes constitute a cellular defense against acute stress, myocardial ischemia reperfusion injury in transgenic mice overexpressing the cellular glutathione peroxidase (GSHPx-1) was studied. Transgenic mice were generated using the entire mouse GSHPx-1 gene including approximately 2.0 kb 5'flanking sequence. A 400% increase of GSHPx activity was found in the hearts of transgenic mice compared with non-transgenic controls. Isolated perfused hearts were prepared from two groups of mice: transgenic overexpressed; non-transgenic controls. Hearts were perfused by Langendorff mode, and after 10 min of stabilization subjected to 30 min of ischemia followed by 20 min of reperfusion. In addition, a group of hearts were perfused for 50 min without subjecting them to ischemia and reperfusion to demonstrate the stability of heart preparation. Transgenic mouse hearts demonstrated significantly improved recovery of contractile force and the rate of contraction, compared to non-transgenic control mouse hearts. The infarct size was also lower in transgenic mouse hearts compared to those of non-transgenic controls. In concert, following ischemia, release of creatine kinase from the transgenic hearts was significantly lower than the control group. The results of this study indicate that increased GSHPx-1 expression renders the heart more resistant to myocardial ischemia reperfusion injury.
J Mol Cell Cardiol 1996 Aug
PMID:Transgenic mice overexpressing glutathione peroxidase are resistant to myocardial ischemia reperfusion injury. 887 85

Elevation of cell iron content was produced by use of a lipophilic iron ligand, 8-hydroxyquinoline (HQ), capable of transferring catalytically active iron into cells. The Fe(3+)-HQ complex labeled with 59Fe was avidly taken up by isolated perfused hearts contrary to the hydrophilic complex Fe(3+)-citrate. Hearts perfused in aerobic conditions with Krebs-Henseleit buffer were exposed for 15 min to the iron complexes, Fe(3+)-HQ (5 microM/10 microM and 10 microM/20 microM), or Fe(3+)-citrate (10 microM), and then perfused for 30 min with normal buffer. Exposure to the high dose of Fe(3+)-HQ (10 microM/20 microM) resulted in early and irreversible decreases in coronary flow and heart rate (-48% and -33%, respectively), initial increases followed by decreases in left ventricular systolic pressure and +dP/dt, and increase in left ventricular end-diastolic pressure (+80%). The low dose of Fe(3+)-HQ (5 microM/10 microM) mimicked with a lower magnitude the effects of the high dose, whereas Fe(3+)-citrate had no effects on cardiac parameters. Only hearts exposed to the high dose of Fe(3+)-HQ exhibited a significant increase (+60%) in thiobarbituric acid-reactive substance level, an index of lipid peroxidation. The production of hydroxyl radicals was investigated by measuring 2,3-dihydroxybenzoic acid level in the coronary effluent after addition of salicylic acid (1 mM) in the perfusate. An immediate and high increase (x6) was seen during heart exposure to Fe(3+)-HQ (10 microM/20 microM) and to Fe(3+)-citrate (10 microM). Considering Fe(3+)-citrate had no effect on cardiac function and lipid peroxidation it was concluded that this hydroxyl radical formation occurring in the extracellular space was not implicated in Fe(3+)-HQ-induced cardiac dysfunction. These results demonstrate the deleterious effect of increasing intracellular reactive iron level in non-ischemic hearts.
J Mol Cell Cardiol 1996 Aug
PMID:Effects of increasing intracellular reactive iron level on cardiac function and oxidative injury in the isolated rat heart. 887 86

The effects of treppe on left ventricular function in the isolated mouse heart perfused with physiological buffer or with erythrocyte-rich buffer were compared. Left ventricular systolic and diastolic pressures were measured in the isovolumically contracting (balloon in the left ventricle) mouse hearts. Hearts were isolated from 12 adult Swiss-Webster mice and perfused at constant pressure (approximately 85 mmHg) via the aorta. Perfusate consisted of non-recirculating oxygenated Krebs-Henseleit (KH) solution without or with washed cow red blood cells at a hematocrit of 20% (KH-RBC20). The measured ionized calcium concentration of the perfusates were adjusted to 2.2 mmol/l and the temperature held constant at 37 degrees C. Left ventricular systolic pressure, its derivative and diastolic pressures were recorded via a pressure transducer attached to a small latex balloon which was placed in the left ventricle through a left atrial incision. The balloon volume was adjusted to achieve an end-diastolic pressure of 4-8 mmHg. Left ventricular (LV) developed pressure averaged 111 +/- 4 (mean +/- S.E.M.) with KH alone and 108 +/- 4 mmHg with KH-RBC20 while the coronary flows were 3.1 +/- 0.18 and 0.95 +/- 0.15 ml/min respectively. In both KH solution alone and KH-RBC20, developed pressure remained relatively stable from 3 to 5 Hz while +/- dp/dt increased approximately 10% above values observed at 3 Hz. During KH perfusion with increasing stimulation rates, left ventricular pressure and +/- dP/dt, to a lesser extent, decreased while end-diastolic pressure markedly increased at stimulation rates higher than 5 Hz. However, KH-RBC20 perfusion prevented the marked increase in diastolic pressure with increasing stimulation rates (from 5 to 10 Hz). No significant difference in left ventricular developed pressure or +/dP/dt response to treppe were in evidence between groups. These results demonstrate that diastolic function of the isovolumically contracting mouse heart is sensitive to treppe and different techniques of perfusion. Buffer perfusion alone may limit accurate measurement of left ventricular diastolic properties and exacerbate changes in diastolic function, particularly under conditions of increased oxygen demand. The erythrocyte perfused mouse heart provides an in vitro model for determining cardiac function which is physiologically superior to buffer perfusion, and may be useful to investigators to assess gene influence on left ventricular function in genetically altered mice.
J Mol Cell Cardiol 1996 Aug
PMID:Effect of treppe on isovolumic function in the isolated blood-perfused mouse heart. 887 91


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