Distinct regulation of the interleukin-1 and interleukin-6 response elements of the rat haptoglobin gene in rat and human hepatoma cells

The transcription rate of the haptoglobin (Hp) gene is stimulated by interleukin-1 (IL-1), IL-6, and dexamethasone in rat hepatoma (H-35) cells. To identify the cis-acting regulatory elements responsive to these hormones, various lengths of 5' Hp gene-flanking regions, including the promoter, were inserted into chloramphenicol acetyltransferase gene expression vectors and transiently introduced into H-35 cells. The first 4 kb of 5' region mediated a severalfold increase in expression after treatment with IL-6 and dexamethasone. No response to IL-1 was detectable. When, however, upstream sequences were deleted to position -165 relative to the transcription start site, a significant stimulation by IL-1 was gained without appreciably affecting the IL-6 response. With the apparent removal of an inhibitory sequence, the promoter-proximal 165-bp region also displayed a severalfold enhanced response to the combination of dexamethasone, IL-1, and IL-6. The sequence from -165 to -147, termed the A-element, was found to be crucial for all hormone regulatory functions. Two copies of the A-element linked to a heterologous promoter responded to the three hormones, but to a lesser degree than in the Hp gene promoter context. The regulatory elements of the rat Hp gene were similarly active in human hepatoma cells. Optimal regulation by IL-6 in HepG2 cells was, however, independent of the A-element. The A-element functioned in these cells exclusively as an IL-1 response sequence. The results suggest that genomic sequences upstream of the rat Hp gene suppress the regulation by specific cytokines more prominently in transient expression assays than in the normal chromosomal context. Moreover, the functional comparison indicated that specific regulatory regions of the rat Hp gene do not function identically in different hepatic cell types.

The cytokine response element of the rat alpha 1-acid glycoprotein gene is a complex of several interacting regulatory sequences

Expression of the rat alpha 1-acid glycoprotein gene is stimulated by interleukin-1 (IL-1) and interleukin-6 (IL-6) and is synergistically enhanced by the combination of the two. The distal regulatory element (DRE), a 142-base-pair (bp) sequence located 5 kilobase pairs upstream of the transcriptional start site, appears to be crucial for this cytokine response. The cytokine-specific regulatory sequences within the DRE have been identified by inserting individual DRE subregions, selected combinations of these, or a few linker mutated fragments into a plasmid containing an enhancerless simian virus 40 promoter linked to the chloramphenicol acetyltransferase gene. The regulatory activity was determined in transiently transfected human and rat hepatoma cells. The IL-1 response region was confined to the 5'-most 62 bp of the DRE, and its function seemed to depend on at least two separate components. The same region was also responsive to phorbol ester treatment. The IL-6 regulatory function was dependent on a 54-bp sequence located within the 3' half of the DRE. When the IL-1 response region was recombined with the IL-6 regulatory region of the DRE or with IL-6 response elements of other plasma protein genes, a strong cooperative action by IL-1 and IL-6 was achieved. The functional DRE sequences were recognized by nuclear proteins extracted from rat liver and hepatoma cells. However, no cytokine-inducible binding activity was detectable, which suggests that transcriptional regulation through the DRE might be controlled by posttranslational modification of constitutively bound trans-acting factors.

Molecular characterization and acute phase expression of the multiple Mus caroli alpha 1-acid glycoprotein (AGP) genes. Differences in glucocorticoid stimulation and regulatory elements between the rat and mouse AGP genes

In this study, we have analyzed alpha 1-acid glycoprotein (AGP) production in the wild mouse strain Mus caroli to assess whether the stimulation of AGP by inflammatory mediators has been conserved during rodent evolution and to determine what DNA elements manifested the hormonal induction in mouse AGP gene sequences. To this end, we isolated the M. caroli AGP genes and characterized their expression. Southern blot hybridization of M. caroli genomic DNA revealed the existence of approximately eight genes per haploid genome, and eight distinct genes were identified from a M. caroli lambda genomic DNA library. Two actively transcribed and acute phase-regulated genes (AGP genes 1 and 8) were identified by sequence correlation with the two different cDNAs isolated from an acute phase liver cDNA library. Two-dimensional gel analysis of in vitro transcription and translation products from these two cDNAs displayed a pattern of protein precursors identical with that shown by in vitro translation of the endogenous AGP mRNA. A glucocorticoid-responsive element (GRE) in M. caroli AGP gene 8 was localized to a unique sequence distal to the relative position of the rat AGP gene GRE. The mouse region analogous to the rat GRE did not show glucocorticoid-mediated induction of an indicator gene although greater than 90% sequence similarity is maintained. GRE function in this mouse region was improved by introducing a point mutation that restores the rat AGP GRE consensus sequence, although the relative induction obtained was less than the wild-type rat AGP GRE.

[Iniencephaly: prenatal and postnatal findings]

A 33-year-old para-3 was admitted in the 33rd week of gestation because of a suspected foetal anomaly. Ultrasound examination showed polyhydramnios, exaggerated cervico-thoracic lordosis and significant shortening of the spine because of a reduced number of vertebrae. The facial profile was flat, the foetal movements were rare and slow, and the extremities normal. A biopsy of the placenta revealed a normal female karyotype. Based on ultrasound examination, the diagnosis of iniencephaly was made. Because of the fatal prognosis of this malformation, labour was induced at 35 weeks of gestation. The patient delivered spontaneously. The infant died after 90 minutes. The postmortem examination confirmed the diagnosis of iniencephaly. Iniencephaly is a very rare malformation comprising a bone defect at the occiput, malformation of the cervical and thoracic vertebrae, spina bifida, and retroflexion of the head. The aetiology is not clear. 90% of the probands are female. The malformation is incompatible with survival after birth.

Inducible and tissue-specific expression of rat alpha-1-acid glycoprotein in transgenic mice

alpha-1-Acid glycoprotein (AGP), which is produced in the mammalian liver and secreted into the blood-stream, is regulated by steroid hormones and by mediators of the acute phase response. In vitro transfection studies have shown that the response to glucocorticoids requires a cis-acting regulatory element, termed the glucocorticoid response element, that is located within 120 bp of the transcriptional start-site of the gene; induction by the acute phase mediators requires a different element, termed the distal regulatory element (DRE), that is located about 5 kb upstream of the start-site. To determine if these elements function in vivo, we have produced and characterized transgenic mice containing rat AGP gene constructs with and without the DRE. Five transgenic lines were produced from a 9.5-kb genomic AGP containing 4.7 kb of the 5' flanking region; this construct lacks the DRE. Another transgenic line was derived from a 10.7-kb clone that contains 5.3 kb of 5' flanking sequences including the DRE. All transgenic mice produced high levels of immunologically detectable rat AGP in the circulation, comparable to or in excess of that found in normal rats. There were correspondingly high concentrations of rat AGP transcripts in the liver. Transgene expression in all lines was induced in response to dexamethasone and during acute inflammation resulting from LPS treatment. The DRE-containing transgene underwent a greater induction in response to LPS than to dexamethasone; the transgene lacking the DRE responded similarly to both treatments. In cultured primary hepatocytes, the DRE-containing transgene was induced by the acute phase cytokines IL-1 and IL-6, and by dexamethasone, administered individually or in combination; the transgene lacking the DRE responded only to dexamethasone, and was not affected by the peptide hormones. Together, these results provide in vivo evidence supporting the notion that a minimum of two upstream sequences are responsible for the inflammatory induction of rat AGP. One element, which is located within the smaller 9.7-kb restriction fragment, is responsive to glucocorticoids and is likely to be the glucocorticoid response element located close to the transcriptional start site. The other element, the DRE, is located much further upstream and is responsible for imparting responsiveness to the acute phase cytokines.

Inducible and tissue-specific expression of rat alpha-1-acid glycoprotein in transgenic mice

alpha-1-Acid glycoprotein (AGP), which is produced in the mammalian liver and secreted into the blood-stream, is regulated by steroid hormones and by mediators of the acute phase response. In vitro transfection studies have shown that the response to glucocorticoids requires a cis-acting regulatory element, termed the glucocorticoid response element, that is located within 120 bp of the transcriptional start-site of the gene; induction by the acute phase mediators requires a different element, termed the distal regulatory element (DRE), that is located about 5 kb upstream of the start-site. To determine if these elements function in vivo, we have produced and characterized transgenic mice containing rat AGP gene constructs with and without the DRE. Five transgenic lines were produced from a 9.5-kb genomic AGP containing 4.7 kb of the 5' flanking region; this construct lacks the DRE. Another transgenic line was derived from a 10.7-kb clone that contains 5.3 kb of 5' flanking sequences including the DRE. All transgenic mice produced high levels of immunologically detectable rat AGP in the circulation, comparable to or in excess of that found in normal rats. There were correspondingly high concentrations of rat AGP transcripts in the liver. Transgene expression in all lines was induced in response to dexamethasone and during acute inflammation resulting from LPS treatment. The DRE-containing transgene underwent a greater induction in response to LPS than to dexamethasone; the transgene lacking the DRE responded similarly to both treatments. In cultured primary hepatocytes, the DRE-containing transgene was induced by the acute phase cytokines IL-1 and IL-6, and by dexamethasone, administered individually or in combination; the transgene lacking the DRE responded only to dexamethasone, and was not affected by the peptide hormones. Together, these results provide in vivo evidence supporting the notion that a minimum of two upstream sequences are responsible for the inflammatory induction of rat AGP. One element, which is located within the smaller 9.7-kb restriction fragment, is responsive to glucocorticoids and is likely to be the glucocorticoid response element located close to the transcriptional start site. The other element, the DRE, is located much further upstream and is responsible for imparting responsiveness to the acute phase cytokines.

Uteroplacental blood flow velocity waveforms in the second and third trimesters of normal pregnancy as related to the placenta location

The systolic/diastolic ratios (A/B) of uteroplacental blood flow velocity waveforms as related to the placenta location were investigated by continuous-wave Doppler ultrasound in 67 normal pregnancies at 18-21 weeks, in 111 at 31-33 weeks, and in 34 at 40-41 weeks of gestation. Using real-time ultrasound, the placenta was located laterally in 48%, posteriorly in 30% and anteriorly in 22% of the pregnancies. A/B values decreased slightly with advancing gestational age. With lateral placenta location, statistically significant higher A/B values were found in vessels on the nonplacental side at 31-33 weeks of gestation (2.07 +/- 0.43 versus 1.74 +/- 0.27; p less than 0.05). In the other gestational age groups there were no statistically significant differences between A/B values in the vessels on the placental and nonplacental sides. There were also no differences in A/B values between left and right uteroplacental vessels with anterior or posterior placenta locations in any of the gestational age groups.

Regulation of hepatic acute phase plasma protein genes by hepatocyte stimulating factors and other mediators of inflammation

The hepatic response to systemic injury is characterized by a co-ordinated increase in the expression of several, functionally essential plasma proteins. The factors responsible for initial hepatic stimulation have been identified and include the cytokines IL-1 (interleukin-1), tumor necrosis factor alpha (TNF alpha), IL-6 (interleukin-6), hepatocyte-stimulating factor-III (HSF-III) as well as corticosteroids. The absolute level of expression of the regulated proteins appears to be modulated by the pre-existing hepatic hormonal environment and changes to that environment that occur during acute phase reactions. The specific effects of glucocorticoids, IL-1 and activation of protein kinase C are addressed in this study. In order to predict the phenotype of liver response in acute phase, the hepatic activities of all inflammatory cytokines present must be established. Moreover, it must be recognized that the hepatic environment itself can modulate the anabolic response of the liver to these cytokines. The same considerations are needed when determining the changes seen during the progression to chronic inflammation.

The acute-phase protein response in parasite infection. Nippostrongylus brasiliensis and Trichinella spiralis in the rat

During acute inflammation, the mammalian liver responds with increased production and secretion of a series of plasma glycoproteins, collectively termed the acute-phase proteins, resulting from the release at the site of inflammation of polypeptide cytokines, including IL-1 and IL-6, which interact with receptors on hepatocytes and alter gene expression. This attribute of the systemic acute-phase response was studied throughout the course of infection with two nematode parasites in rats. Significant increases in serum haptoglobin, alpha 1-acid glycoprotein and alpha 1-cysteine protease inhibitor were detected coincident with episodes of skin, lung and intestinal pathology during Nippostrongylus brasiliensis, but were not seen during Trichinella spiralis, infection of the rat despite similar intestinal pathology. These changes were seen at both the protein and mRNA levels in the liver. Infection with T. spiralis was not anti-inflammatory, as macrophages from various sites could be induced in vitro to release inflammatory cytokines, and in vivo induction of inflammation by turpentine injection was similar in control and infected animals. However, macrophage populations recovered from animals infected with T. spiralis were not activated. Moreover, intestinal infection alone with intestinal stages of N. brasiliensis also failed to elicit the systemic acute-phase protein response, requiring an explanation involving skin and lung for the acute-phase response during gut inflammation in a primary infection with N. brasiliensis. Taken together, these data suggest that during the intestinal phase of nematode infection, with pathological changes to the gut, the systemic acute-phase response is not elicited through compromise or lack of stimulation of inflammatory cells in the intestine. The systemic parameters of the acute-phase response may not be a component of gastrointestinal pathology.

Structure, hormonal regulation, and identification of the interleukin-6- and dexamethasone-responsive element of the rat haptoglobin gene

Hepatic expression of the haptoglobin (Hp) gene in mammalian species is stimulated severalfold during an acute-phase reaction. To identify the molecular mechanism responsible for this regulation, the single-copy rat Hp gene has been isolated. The genomic sequences showed a high degree of homology with the primate Hp gene. Activity of the rat Hp gene was increased in cultured liver cells by interleukin-1 (IL-1), IL-6, and glucocorticoids. The genomic Hp gene sequence spanning from -6500 to +6500, when transiently introduced into human hepatoma (HepG2) cells, directed IL-6- and dexamethasone-stimulated expression of rat Hp mRNA and protein. No response to IL-1 was detected, suggesting that the corresponding regulatory element(s) might lie outside of the tested gene sequences. An IL-6- and dexamethasone-responsive element has been localized to the promoter proximal region -146 to -55. Although the nucleotide sequences of this rat Hp gene region showed substantial divergence from that of the human gene, analysis of sequential 5' and 3' deletion constructs indicated an arrangement of functional IL-6 response elements in the rat Hp promoter sequence comparable to that of the human homolog. The magnitude of IL-6 regulation through the rat Hp gene promoter was severalfold lower than that of the human Hp gene. The reduced activity could be ascribed to a single-base difference in an otherwise conserved sequence corresponding to an active element in the human gene. The IL-6 response of the rat Hp element was improved severalfold by substituting that base with the human nucleotide.

Fermentation of bovine endothelial cells for preparation of endothelial cell-surface heparan sulphate

The polysaccharide chains of a proteoheparan sulphate located on the endothelial cell surface are responsible for athrombogenicity of blood vessel walls. Mass cultivation of endothelial cells is the only way to isolate adequate amounts of this proteoheparan sulphate. In order to establish a method for fermentation of bovine endothelial cells, colonization of microcarriers, growth phase and cultivation of confluent carriers were optimized. The colonization process was varied relative to the number of beads, number of cells, total volume and kind of vessel. Two basal media were tested at different serum contents by growth assays. The same basal media without serum were supplemented with mitogen, bovine lipoprotein, insulin and transferrin and tested by activity assays on confluent cultures. The best method yields more than 80% of the cells on microcarriers. During the fermentation glucose and lactate concentrations were measured at constant perfusion rate and glucose consumption and lactate production were determined. Under optimized conditions we achieved a final cell titre of 4 x 10(9) cells/l and a calculated cell density of 7-9 x 10(4) cells/cm2 offered substrate surface. The minimal doubling time of the cell culture was about 18 h under optimized fermentation conditions. Removal of the core-protein by enzymatic digestion or beta-elimination releases the endothelial cell surface heparan sulphate.

Intravenous thrombolytic therapy with a combination of single-chain urokinase-type plasminogen activator and recombinant tissue-type plasminogen activator in acute myocardial infarction

The effects of simultaneous intravenous infusions of 12 mg recombinant tissue-type plasminogen activator (rt-PA) over 30 minutes and 48 mg single-chain urokinase-type plasminogen activator (scuPA) over 40 minutes were studied in 38 patients with acute myocardial infarction. Coronary arterial patency was assessed angiographically 60 minutes and 90 minutes after initiation of treatment. Patency was achieved in 19 of 31 patients (61.3%) (95% confidence limits, 42-78%) at 60 minutes and in 27 of 33 patients (81.8%) (95% confidence limits, 65-93%) at 90 minutes. Nonspecific plasminogen activation was monitored by measuring relevant plasma parameters. At 60 minutes and 120 minutes, the fibrinogen concentration decreased slightly to 82.8 +/- 24.3% and 91.2 +/- 17.4% of the preinfusion level, and the plasminogen concentration to 66.3 +/- 15.2% and 65.3 +/- 13.4%, respectively. A greater consumption of alpha 2-antiplasmin was observed, which decreased to 30.7 +/- 22.8% and 32.2 +/- 21.2% of the preinfusion level at 60 and 120 minutes, respectively. No bleeding necessitating transfusion was observed. Two patients (5.3%) died during hospitalization. The findings suggest that the combined intravenous infusion of rt-PA and scuPA at appropriate doses induces highly effective coronary thrombolysis equal to the best results obtained with either rt-PA or scuPA alone. This efficacy is coupled with high specificity. Thus, the data support the potential use of combinations of rt-PA and scuPA in place of monotherapy.

Effect of epidural anesthesia for cesarean delivery on maternal femoral arterial and venous, uteroplacental, and umbilical blood flow velocities and waveforms

The effect of epidural anesthesia on the maternal femoral arterial and venous, uteroplacental, and umbilical circulations was studied by the pulsed Doppler technique in 13 women undergoing elective cesarean delivery. Resistance and pulsatility indices of umbilical arterial velocity waveforms did not change with the use of epidural anesthesia. In the uteroplacental circulation, these indices increased in 11 patients, suggesting an increase in resistance. Reduction of sympathetic tone in resistance and capacitance vessels was reflected in the femoral artery by an increase in systolic and end-diastolic velocities, a reversal of the post-systolic backward flow, and an increase in mean velocity. The latter also occurred in the femoral vein. The diameters of these large maternal vessels did not change. This study suggests an impairment in uteroplacental circulation associated with a drop in peripheral vascular resistance and an increase in leg blood flow after epidural anesthesia.

Highly conserved upstream regions of the alpha 1-antitrypsin gene in two mouse species govern liver-specific expression by different mechanisms

alpha 1-Antitrypsin (AT), the major elastase inhibitor in mammalian serum, is produced primarily in the liver. We have characterized AT gene structure and expression in the mouse species Mus caroli, which expresses high levels of AT in the kidneys as well as in the liver. Analysis of cDNA and genomic clones showed that the AT gene in M. caroli exhibits high sequence homology (greater than 90%) to the gene in laboratory mice (M. domesticus) throughout the coding and 5'-flanking regions. Despite this extensive sequence conservation, the functional organization of cis-acting regulatory elements governing liver-specific expression is strikingly different between these species. Transient-transfection assays showed that the proximal region of the M. caroli promoter (i.e., between -120 and -2 relative to the transcriptional start site) is 10-fold more active than the analogous region of M. domesticus in driving the expression of an indicator gene in cultured liver cells. The increased activity of the proximal region of the M. caroli AT promoter appears to be the result of one or both of the two base substitutions at positions -46 and -48. The weak proximal promoter in M. domesticus is compensated for by the presence of upstream, liver-specific enhancers between -199 and -520; the analogous region in M. caroli is inactive. Thus, during the course of evolution, the modest 7% sequence divergence that has occurred between the 5'-flanking regions of the AT genes in these two species has generated distinct, yet equally effective, modes of hepatocyte-specific expression.

Uteroplacental blood flow velocity waveforms as a predictor of adverse fetal outcome and pregnancy-induced hypertension

The resistance index (RI) of uteroplacental blood flow velocity waveforms (VWF) was investigated by continuous Doppler ultrasound in 286 nonselected pregnant women with singleton pregnancies at 18-21 weeks (n = 129) and at 31-33 weeks (n = 157) of gestation to evaluate the validity of this method as a screening procedure for abnormal pregnancy outcome (intrauterine growth retardation, pregnancy-induced hypertension and fetal asphyxia). The sensitivity of predicting pregnancy outcome was 26.6% at 18-21 weeks and 17.6% at 31-33 weeks of gestation. It was concluded that this method is too insensitive as a screening tool for the prediction of intrauterine growth retardation and pregnancy-induced hypertension in a low-risk nonselected pregnant population.

Peptide diazomethyl ketones are inhibitors of subtilisin-type serine proteases

Peptide diazomethyl ketones, well known as specific cysteine protease inhibitors are also potent inhibitors of the microbial serine proteases thermitase (EC 3.4.21.14) and subtilisin Carlsberg (EC 3.4.21.14). The affinity of the enzymes towards the synthetic inhibitors Z-Ala(n)-PheCHN2 (n = 0, 1, 2) depends on the chain length and is in the same range as for the corresponding chloromethyl ketones. Both kinds of inhibitors react irreversibly in a 1:1 ratio with the enzymes and covalently bind to the active site histidine of both subtilisin Carlsberg and thermitase despite the fact that thermitase contains an active-site cysteinyl residue. The mechanism of the inhibition reaction is discussed.

Hepatocyte-stimulating factor III shares structural and functional identity with leukemia-inhibitory factor

The coordinate increase in the hepatic production of the acute phase plasma proteins appears to be mediated by several cytokines produced by different cell types. One factor, hepatocyte-stimulating factor III (HSF-III), constitutively produced by human squamous carcinoma (COLO-16) cells, stimulates the synthesis of the same set of acute phase plasma proteins as the structurally distinct IL-6. The physicochemical properties of HSF-III coincide with those of the T cell-derived leukemia-inhibitory factor (LIF). Human rLIF, tested on hepatoma cells, indicated a liver-regulating activity identical to HSF-III. The LIF activity is specifically neutralized by HSF-III antibodies. COLO-16 cells contain an LIF mRNA which is characteristic for lectin-stimulated T cells, suggesting that HSF-III is an epidermal cell-derived form of LIF. This result provides additional evidence for the close relationship between acute phase regulation of the liver and control of proliferation and differentiation of hemopoietic cells by identical cytokines.

Hepatocyte-stimulating factor III shares structural and functional identity with leukemia-inhibitory factor

The coordinate increase in the hepatic production of the acute phase plasma proteins appears to be mediated by several cytokines produced by different cell types. One factor, hepatocyte-stimulating factor III (HSF-III), constitutively produced by human squamous carcinoma (COLO-16) cells, stimulates the synthesis of the same set of acute phase plasma proteins as the structurally distinct IL-6. The physicochemical properties of HSF-III coincide with those of the T cell-derived leukemia-inhibitory factor (LIF). Human rLIF, tested on hepatoma cells, indicated a liver-regulating activity identical to HSF-III. The LIF activity is specifically neutralized by HSF-III antibodies. COLO-16 cells contain an LIF mRNA which is characteristic for lectin-stimulated T cells, suggesting that HSF-III is an epidermal cell-derived form of LIF. This result provides additional evidence for the close relationship between acute phase regulation of the liver and control of proliferation and differentiation of hemopoietic cells by identical cytokines.

Surgical treatment of myeloradiculopathy in cervical spondylosis. A report on 438 operations

In the past eleven years we have performed 438 microsurgical ventral discectomies with bilateral foraminotomy followed by fusion with palacos in the cervical spine in our clinic. An analysis of the preoperative symptoms shows a great variability and overlapping of the various segments. To determine the right level for the operation it is crucial that the results of the clinical and the radiological examinations be evaluated. The results of ascending myelography and CT scans are of great value. In cases of cervical myelopathy a multisegmental operation is often necessary to obtain good results. The complication rate was small in our patients and a second operation was only necessary in a few cases. We had very good postoperative results in radicular pain and muscle weakness. In patients with symptoms of cervical myelopathy we achieved considerable improvement.