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Publication
Journal: Journal of the National Cancer Institute
September/14/1981
Abstract
The hormonal environments require by human breast cancer cells MCF-7 to produce solid tumors in nude mice are described. A 100% take was obtained within 7 days following inoculation of 2X10(6) actively growing (log phase) MCF-7 cells into the mammary fat pads of intact, athymic BALB/c nude mice. Tumors failed to develop, even with an inoculum of 20X10(6) cells/mouse, in ovariectomized mice or in mice made diabetic with streptozotocin and observed for 90 days after cell inoculation. A 100% incidence of tumors was obtained in mice that were either hypophysectomized or made diabetic but received injections of 0.2 IU insulin/day/mouse. A 100% incidence of tumors was also obtained in ovariectomized mice that received 17 beta-estradiol in the form of a pellet placed subcutaneously in the interscapular region at the time of cell inoculation. Palpable tumors also developed in ovariectomized mice treated with prolactin, perphenazine, estrone, or estriol, but no takes were observed in ovariectomized mice treated with progesterone, 5 alpha-dihydrotestosterone, or hydrocortisone. Growth of the MCF-7 tumor was stimulated five- to sixfold in both intact and hypophysectomized mice that each received a 17 beta-estradiol pellet. Removal of the 17 beta-estradiol pellets form tumor-bearing ovariectomized mice failed to induce tumor regression. Tumors that continued to grow in ovariectomized mice deprived of 17 beta-estradiol regressed by 50% or more of their initial volume when tamoxifen was injected for 7 days at 5 micrograms/mouse/day) +/- theophyline (1 mg/mouse/day), tumor growth arrest was observed during the 2-to 3-week treatment period. Streptozotocin-induced diabetes in tumor-bearing mice always resulted in complete tumor regression following a 3-week treatment period.
Publication
Journal: Journal of NeuroVirology
February/19/1997
Abstract
We report here the results of therapeutic trials in 200 patients with HTLV-I-associated myelopathy (HAM)/tropical spastic paraparesis (TSP) conducted in our department between 1986 and 1993. Motor disability grades were improved by more than one grade in 69.5% (91/131) of patients by oral administration of prednisolone, 50% (3/6) by eperisone hydrochloride only, 43.8% (7/16) by blood purification (lymphocytapheresis and plasmapheresis), 40.0% (2/5) by intrathecal injection of hydrocortisone, 30.0% (3/10) by intravenous injection of high-dose methylprednisolone, 23.3% (10/43) by interferon-alpha (intramuscular injection and inhalation), 22.2% (2/9) by azathioprine, 20.0% (4/20) by high-dose vitamin C, 16.0% (4/25) by erythromycin, 12.5% (3/24) by salazosulfapyridine, 11.8% (2/17) by mizoribine, 7.1% (1/14) by fosfomycin, and 6.3% (1/16) by thyrotropin releasing hormone. No critical side effects of these therapies were seen with the exceptions of one patient with adult respiratory distress syndrome due to cytomegalovirus infection and one patient with drug-induced hepatitis/hepatic failure. Selection of these treatments for patients with HAM/ TSP must be considered on the basis of age, sex, disease severity and complications to reduce adverse events and to improve quality of life. Although the results were a synopsis of different treatments given to 200 patients with HAM/ TSP as an open trial, we consider this the first report of a large-scale therapeutic trial in patients with HAM/TSP. The results of this study indicate that immunomodulatory therapies have some beneficial effects in HAM/TSP, and the functions of these agents are related to the pathophysiology of this disease.
Publication
Journal: In Vitro Cellular and Developmental Biology - Animal
January/1/1997
Abstract
During angiogenesis, the microvasculature displays both vessel remodeling and expansion under the control of both cellular and extracellular influences. We have evaluated the role of angiogenic and angiostatic molecules on angiogenesis in an in vitro model that more appropriately duplicates the cellular and extracellular components of this process. Freshly isolated microvessel fragments from rat adipose tissue (RFMF) were cultured within three-dimensional collagen I gels. These fragments were characterized at the time of isolation and were composed of vessel segments observed in the microvasculature of fat in situ (i.e., arterioles, venules, and capillaries). Fragments also exhibited characteristic ablumenally associated cells including smooth muscle cells and pericytes. Finally, fragments were encased in an extracellular matrix composed of collagen type IV and collagen type I/III. The elongation of microvascular elements was subsequently evaluated using morphologic and immunocytochemical techniques. The proliferation, migration, and elongation of cellular elements in microvessel fragments from rat adipose tissue was dependent on initial fragment density, matrix density, and required serum. Inclusion of endothelial cell growth factors to microvessel fragments from rat adipose tissue 3-D cultures resulted in the accelerated elongation of tube structures and the expression of von Willebrand factor in cells constituting these tubes. Molecules with reported angiostatic capacity (e.g., transforming growth factor and hydrocortisone) inhibited vessel tube elongation. In vitro methods have been developed to evaluate numerous mechanisms associated with angiogenesis, including endothelial cell proliferation, migration, and phenotypic modulation. Microvascular endothelial cell fragments described in this study represent an in vitro population of cells that accurately duplicate the in vivo microcirculatory elements of fat. The proliferation of cells and elongation of microvascular elements subsequently observed in three-dimensional cultures provides an in vitro model of angiogenesis. Microvascular formation in this system results from pre-existing microvessel fragments unlike tube formation observed when cultured endothelial cells are placed in three-dimensional gels. This form of tube formation from cultured endothelium is more characteristic of vasculogenesis. Thus, the formation of microvascular elements from microvessel fragments provides the opportunity to examine the mechanisms regulating angiogenesis in an in vitro system amenable to precise experimental manipulation.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
February/10/2004
Abstract
The present study was designed to examine the hypothesis that hypothalamic-pituitary-adrenal axis activity as measured by 24-h cortisol production rate (CPR) and plasma levels of free cortisol is linked to increased body fat in adults, and that increased cortisol levels with aging results from increased CPR. Fifty-four healthy men and women volunteers with a wide range of body mass indexes and ages underwent measurement of CPR by isotope dilution measured by gas chromatography-mass spectroscopy, cortisol-binding globulin, and free cortisol in pooled 24-h plasma, body composition, and leptin. Cortisol clearance rates were determined from the 10-h disappearance curves of hydrocortisone after steady-state infusion in a separate group of lean and obese subjects with adrenal insufficiency. Although CPR significantly increased with increasing body mass index and percentage body fat, free cortisol levels remained independent of body composition and leptin levels due to increased cortisol clearance rates. CPR and free cortisol levels were, however, significantly higher in men than women. In addition, 24-h plasma free cortisol levels were increased with age in association with increased CPR, independent of body size. This increase in hypothalamic-pituitary-adrenal axis activity may play a role in the alterations in body composition and central fat distribution in men vs. women and with aging.
Publication
Journal: Journal of Biological Chemistry
November/3/1994
Abstract
This study demonstrates that the expression of the peroxisome proliferator-activated receptor alpha (PPAR alpha) is regulated by glucocorticoid hormones in hepatocytes. Hydrocortisone, dexamethasone, and triamcinolone stimulated PPAR alpha mRNA synthesis in a dose-dependent manner in primary rat hepatocyte cultures. This glucocorticoid stimulation was inhibited by RU 486, a specific glucocorticoid antagonist. Moreover, in contrast to glucocorticoid hormones, the mineralocorticoid aldosterone had only a weak effect, suggesting that the hormonal stimulation of PPAR alpha was mediated by the glucocorticoid receptor. The induction was not prevented by cycloheximide treatment of the hepatocytes, indicating that it was mediated by preexisting glucocorticoid receptor. Finally, the RNA synthesis inhibitor actinomycin D abolished the stimulatory effect of dexamethasone, and nuclear run-on analysis showed an increase of PPAR alpha transcripts after hormonal induction. Thus, the PPAR alpha gene is an early response gene of glucocorticoids that control its expression at the transcriptional level.
Publication
Journal: The Journal of investigative dermatology
October/7/2010
Abstract
Keloids are benign dermal tumors that form during wound healing in genetically susceptible individuals. The mechanism(s) of keloid formation is unknown and there is no satisfactory treatment. We have reported differences between fibroblasts cultured from normal scars and keloids that include a pattern of glucocorticoid resistance and altered regulation of genes in several signaling pathways associated with fibrosis, including Wnt and IGF/IGF-binding protein 5 (IGFBP5). As previously reported for glucocorticoid resistance, decreased expression of the Wnt inhibitor secreted frizzled-related protein 1 (SFRP1), matrix metalloproteinase 3 (MMP3), and dermatopontin (DPT), and increased expression of IGFBP5 and jagged 1 (JAG1) are seen only in fibroblasts cultured from the keloid nodule. In vivo, decreased expression of SFRP1 and SFRP2 and increased expression of IGFBP5 proteins are observed only in proliferative keloid tissue. There is no consistent difference in the replicative life span of normal and keloid fibroblasts, and the altered response to hydrocortisone (HC) and differential regulation of a subset of genes in standard culture medium are maintained throughout at least 80% of the culture lifetime. Preliminary studies using ChIP-chip analysis, Trichostatin A, and 5-aza-2'-deoxycytidine further support an epigenetically altered program in keloid fibroblasts that includes an altered pattern of DNA methylation and histone acetylation.
Publication
Journal: American Journal of Physiology - Renal Physiology
September/17/2002
Abstract
Insulin is an important regulator of renal salt and water excretion, and hyperinsulinemia has been implicated to play a role in hypertension. One of the target proteins of insulin action in the kidney is Na(+)/H(+) exchanger 3 (NHE3), a principal Na(+) transporter responsible for salt absorption in the mammalian proximal tubule. The molecular mechanisms involved in activation of NHE3 by insulin have not been studied so far. In opossum kidney (OK) cells, insulin increased Na(+)/H(+) exchange activity in a time- and concentration-dependent manner. This effect is due to activation of NHE3 as it persisted after pharmacological inhibition of NHE1 and NHE2. In the early phase of stimulation (2-12 h), NHE3 activity was increased without changes in NHE3 protein and mRNA. At 24 h, enhanced NHE3 activity was accompanied by an increase in total and cell surface NHE3 protein and NHE3 mRNA abundance. All the effects of insulin on NHE3 activity, protein, and mRNA were amplified in the presence of hydrocortisone. These results suggest that insulin stimulates renal tubular NHE3 activity via a biphasic mechanism involving posttranslational factors and an increase in NHE3 gene expression and the effects are dependent on the permissive action of hydrocortisone.
Publication
Journal: Brain Research
July/23/2007
Abstract
Physiological studies of the blood-brain barrier (BBB) are often performed in rats. We describe the functional characterization of a reproducible in vitro model of the rat BBB and its validation for investigating mechanisms involved in BBB regulation. Puromycin-purified primary cultures of brain endothelial cells, co-cultured with astrocytes in the presence of hydrocortisone (HC) and cAMP, presented low sucrose permeability (< or =0.1 x 10(-3) cm/min) and high transendothelial electrical resistance >> or =270 Omega cm(2)). Expression of specific BBB markers and their transcripts was detected by immunostaining and RT-PCR, respectively: tight junction proteins (claudin-3 and -5, ZO-1 and occludin) and transporters (P-gp, Bcrp and Oatp-2). RT-PCR experiments demonstrated a role of treatment by astrocytes, HC and cAMP in regulation of the transcript level of tight junction proteins (claudin-5 and ZO-1) as well as transporters (Mdr1a, Mrp3, Mrp4, Bcrp, Glut-1), while transcript level of Mdr1b was significantly decreased. The functionality of efflux pumps (P-gp, Mrps and Bcrp) was demonstrated in the presence of specific inhibitors (PSC833, MK571 or Ko143, respectively) by (i) assessing the uptake of the common substrates rhodamine 123 and daunorubicin and (ii) evaluating apical to basolateral and basolateral to apical polarized transport of daunorubicin. In addition, a good correlation (R=0.94) was obtained between the permeability coefficients of a series of compounds of various lipophilicity and their corresponding in vivo rodent blood-brain transfer coefficients. Taken together, our results provide compelling evidence that puromycin-purified rat brain endothelial cells constitute a reliable model of the rat BBB for physiological and pharmacological characterization of BBB transporters.
Publication
Journal: Molecular Pharmacology
January/17/2001
Abstract
The barbiturate phenobarbital induces the transcription of cytochromes P450 (CYPs) 2B through the constitutive androstane receptor (CAR; NR1I3). CAR is a member of the nuclear receptor family (NR1) mostly expressed in the liver, which heterodimerizes with retinoid X receptor (RXR) and was shown to transactivate both the phenobarbital responsive element module of the human CYP2B6 gene and the CYP3A4 xenobiotic response element. Because previous studies in rodent hepatocyte cultures have shown that the phenobarbital-mediated induction of CYP2B genes is potentiated by glucocorticoids, we examined the role of activated glucocorticoid receptor in this process. We show that submicromolar concentrations of dexamethasone enhance phenobarbital-mediated induction of CYP3A4, CYP2B6, and CYP2C8 mRNA in cultured human hepatocytes. In parallel, we observed that glucocorticoid agonists, such as dexamethasone, prednisolone, or hydrocortisone, specifically increase human car (hCAR) mRNA expression. Accumulation of hCAR mRNA parallels that of tyrosine aminotransferase: both mRNAs reach a maximum at a concentration of 100 nM dexamethasone and are down-regulated by concomitant treatment with the glucocorticoid antagonist RU486. Moreover, the effect of dexamethasone on hCAR mRNA accumulation appears to be of transcriptional origin because the addition of protein synthesis inhibitor cycloheximide has no effect, and dexamethasone does not affect the degradation of hCAR mRNA. Furthermore, dexamethasone increases both basal and phenobarbital-mediated nuclear translocation of CAR immunoreactive protein in human hepatocytes. The up-regulation of CAR mRNA and protein in response to dexamethasone explains the synergistic effect of this glucocorticoid on phenobarbital-mediated induction of CYP2B genes and the controversial role of the glucocorticoid receptor on phenobarbital-mediated CYP gene inductions.
Publication
Journal: Journal of Experimental Medicine
April/30/2003
Abstract
Inoculation of the CAM of the 10-day chick embryo with endotoxin preparations derived from the meningococcus and other Gram-negative microorganisms has been shown to result in multiple hemorrhages and death of the embryo within a few hours. Evidence has been presented to indicate that this lethal effect is specific for the general class of endotoxins derived from Gram-negative bacteria. Susceptibility to endotoxin was maximal in 10-day old embryos, and younger or older embryos showed little or no response. The optimal incubation temperature for the effect of endotoxin was 39.5 degrees C., and embryos incubated at 28 degrees C. were completely protected. The lethal effect was prevented by small amounts of cortisone, hydrocortisone, and 9-alpha fluorohydrocortisone, but not by cholesterol, desoxycorticosterone, or 1-dehydrocortisone.
Publication
Journal: Journal of Biological Chemistry
May/26/1977
Abstract
Primary liver cells, isolated from 16- 17-day-old chick embryos, were incubated in a serum-free chemically defined medium (Ham's F12) supplemented with hormones for up to 6 days. The culture method also includes the complete removal of contaminating red cells before the initiation of culture. On the 2nd day in cluture, the level of amino-levulinate (ALA) synthase activity in response to allylisopropylacetamide (AIA) was increased 6-fold in cells grown in F12. Insulin, hydrocortisone, and triiodothyronine alone had no appreciable effects on ALA synthase levels. On the other hand, when added with AIA, insulin, insulin plus hydrocortisone, insulin plus hydrocortisone triiodothyronine increased ALA synthase levels 17-, 50-, 110-fold, respectively. The maximally induced levels of ALA synthase activity by AIA in the presence of insulin, hydrocortisone, and triiodothyronine were approximately 15 nmol of ALA/mg of protein/h, 37 degrees or 3 micronmol of ALA/g of tissue/h, 37 degrees, a value similar to that found in ovo or at least 5 times greater than that found in rat liver. The morphology of hepatocytes was maintained for at least 6 days in culture, although the induction of ALA synthase was reduced after the 4th day unless triiodothyronine was present. Dibutyryl adenosine 3':5'-monophosphate (10(8) M) or glucagon (5x10(8) M) had little effect on the induced as well as noninduced levels of ALA synthase or porphyrins. These data demonstrate a "permissive" effect of insulin, hydrocortisone, and triiodothyronine on the induction of ALA synthase and porphyrins by AIA in cultured chick embryo liver cells. In the absence of insulin hydrocortisone, or triiodothyronine, AIA produces only a slight increase in ALA synthase activity or porphyrins (or both); on the other hand, it produces a marked increase in the enzyme activity and porphyrins when these hormones are added to the culture medium. The term "permissive" is applied to these hormone-dependent effects. A sensitive spectrofluorometric method for heme quantitation allowed us to follow changes in the cellular heme content in hemoglobin-free cultured liver cells. Heme content in the cultured liver cells was approximately 250 pmol/mg of protein at the initiation of culture but gradually declined to 175 pmol/mg of protein at the initiation of culture but gradually declined to 175 pmol/mg of protein during 48 h of incubation. The apparent decrease in heme content may be accounted for by the concomitant increase in protein content in these cells.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
November/24/1980
Abstract
A human colon carcinoma cell line, HC84S, was established in serum-supplemented medium from a colon tumor line T84 transplanted in nude mice. These cells also grew in a serum-free, synthetic medium supplement with insulin, glucagon, epidermal growth factor, transferrin, hydrocortisone, triiodothyronine, selenium, and ascorbic acid. HC84S cells grew 3 times faster in this medium than in serum-containing medium and formed gland-like structures closely resembling the original tumor morphologically. In serum-containing medium, the cells grew as a monolayer and did not form such structures. Primary cultures from transplantable human colon tumor lines maintained in nude mice and a primary tumor from a patient were established directly in this hormone-supplemented medium in collagen-treated plastic dishes without fibroblast overgrowth. The hormone-supplemented medium may be generally useful for the establishment of human colon carcinoma cell lines.
Publication
Journal: Critical Care Medicine
November/19/2012
Abstract
OBJECTIVE
Acquired glucocorticoid resistance frequently complicates the therapy of sepsis. It leads to an exaggerated proinflammatory response and has been related to altered expression profiles of glucocorticoid receptor isoforms glucocorticoid receptor-α (mediating anti-inflammatory effects) and glucocorticoid receptor-β (acting as a dominant negative inhibitor). We investigated the impact of glucocorticoid receptor isoforms on glucocorticoid effects in human T-cells. We hypothesized that 1) changes of the ratio of glucocorticoid receptor isoforms impact glucocorticoid resistance and 2) glucocorticoid receptor-α expression is controlled by microRNA-mediated gene silencing.
METHODS
Laboratory-based study.
METHODS
University research laboratory.
METHODS
Healthy volunteers, sepsis patients.
METHODS
First, T-cells from healthy volunteers (native and CD3/CD28-stimulated cells with or without addition of hydrocortisone) were analyzed for the expression of glucocorticoid receptor-isoforms by quantitative polymerase chain reaction. Additionally, effects of gene silencing of glucocorticoid receptor-β by siRNA transfection were determined. Secondly, microRNA-mediated silencing was evaluated by cloning of a glucocorticoid receptor-α-specific 3'-untranslated-region reporter construct and subsequent transfection experiments in cell cultures. Effects of miRNA transfection on glucocorticoid receptor-α expression were analyzed in Jurkat T-cells and in T-cells from healthy volunteers (quantitative polymerase chain reaction and Western blotting). Finally, expression of glucocorticoid receptor-α, glucocorticoid receptor-β, and miR-124 was tested in T-cells of sepsis patients (n=24).
RESULTS
Stimulation of T-cells induced a significant upregulation of glucocorticoid receptor-α (not glucocorticoid receptor-β) thereby possibly rendering T-cells more sensitive to glucocorticoids; this T-cell response was hindered by hydrocortisone. Silencing of glucocorticoid receptor-β doubled the inhibitory effects of glucocorticoids on interleukin-2 production. MicroRNA-124 was proved to specifically downregulate glucocorticoid receptor-α. Furthermore, a glucocorticoid-induced three-fold upregulation of microRNA-124 was found. T-cells of sepsis patients exhibited slightly decreased glucocorticoid receptor-α and slightly increased miR-124 expression levels, whereas glucocorticoid receptor-β expression was two-fold upregulated (p<.01) and exhibited a remarkable interindividual variability.
CONCLUSIONS
Glucocorticoid treatment induces expression of miR-124, which downregulates glucocorticoid receptor-α thereby limiting anti-inflammatory effects of glucocorticoids. Steroid treatment might aggravate glucocorticoid resistance in patients with high glucocorticoid receptor-β levels.
Publication
Journal: Intensive Care Medicine
August/20/2013
Abstract
OBJECTIVE
To provide clinicians practicing in resource-limited settings with a framework to improve the diagnosis and treatment of pediatric and adult patients with sepsis.
METHODS
The medical literature on sepsis management was reviewed. Specific attention was paid to identify clinical evidence on sepsis management from resource-limited settings.
RESULTS
Recommendations are grouped into acute and post-acute interventions. Acute interventions include liberal fluid resuscitation to achieve adequate tissue perfusion, normal heart rate and arterial blood pressure, use of epinephrine or dopamine for inadequate tissue perfusion despite fluid resuscitation, frequent measurement of arterial blood pressure in hemodynamically unstable patients, administration of hydrocortisone or prednisolone to patients requiring catecholamines, oxygen administration to achieve an oxygen saturation >90%, semi-recumbent and/or lateral position, non-invasive ventilation for increased work of breathing or hypoxemia despite oxygen therapy, timely administration of adequate antimicrobials, thorough clinical investigation for infectious source identification, fluid/tissue sampling and microbiological work-up, removal, drainage or debridement of the infectious source. Post-acute interventions include regular re-assessment of antimicrobial therapy, administration of antimicrobials for an adequate but not prolonged duration, avoidance of hypoglycemia, pharmacological or mechanical deep vein thrombosis prophylaxis, resumption of oral food intake after resuscitation and regaining of consciousness, careful use of opioids and sedatives, early mobilization, and active weaning of invasive support. Specific considerations for malaria, puerperal sepsis and HIV/AIDS patients with sepsis are included.
CONCLUSIONS
Only scarce evidence exists for the management of pediatric and adult sepsis in resource-limited settings. The presented recommendations may help to improve sepsis management in middle- and low-income countries.
Publication
Journal: Journal of Clinical Investigation
August/16/1999
Abstract
Early-phase reactions (EPRs) and late-phase reactions (LPRs) are characteristic features of bronchial asthma, although the pathogenetic mechanisms responsible for each of the responses are not fully defined. A murine model of EPRs and LPRs was developed to investigate the role of IL-5 and eosinophils in development of both responses. After initial intraperitoneal sensitization and airway challenge to ovalbumin (OVA), mice were provoked by additional exposure to OVA. An EPR, characterized by a transient increase in airway responsiveness, was observed 5-30 minutes after antigen provocation. This response was followed by an LPR that reached its maximum at 6 hours after challenge and was characterized by increased airway responsiveness and significant lung eosinophilia. The EPR was blocked by cromoglycate and albuterol, whereas the LPR was abolished by cromoglycate and hydrocortisone. Before provocation with allergen, administration of anti-IL-5 antibody prevented the influx of eosinophils into the lung tissue and abolished the LPR but not EPR. These results suggest that IL-5 and eosinophils are essential for development of the LPR, but not EPR, in this model.
Publication
Journal: Journal of Allergy and Clinical Immunology
August/9/1972
Publication
Journal: Cell
September/24/1979
Abstract
In this study, the growth of rat follicular (RF-1) cells was severely depressed when the cells were subcultured by trypsinization directly into serum-free medium supplemented with insulin, transferrin and hydrocortisone, which are required for growth of these cells in vitro. Within 24 hr after plating, 50-65% of the cells became binucleated, indicating lack of cytokinesis. However, the addition of human plasma fibronectin (8 microgram/ml) to the serum-free medium eliminated cell binucleation and enhanced cell growth considerably. Fibronectin had the same effect when RF-1 cells were plated into tissue culture dishes on which fibronectin had been absorbed, and cells were inoculated into fibronectin-free medium. Cell binucleation and poor growth in serum-free medium occurred when the cells were subcultured by trypsinization, EGTA treatment or detachment of mitotic cells. Under some conditions, cells could be "rescued" if fibronectin was added soon after inoculation, indicating that fibronectin was needed mainly during a limited time when the subcultured cells were attaching to the tissue culture substratum. Our findings describe an adhesive activity for fibronectin which circumvents the serum preincubation usually needed after RF-1 cells are subcultured for growth in serum-free medium. They also indicate the importance of fibronectin-mediated adhesion for cytokinesis processes of these cells.
Authors
Publication
Journal: Journal of Immunology
September/26/1991
Abstract
Induction of IgE synthesis in human B cells requires two signals. The first signal is delivered by the cytokine IL-4. The second signal activates B cells and is delivered by T cells, EBV infection, or engagement of the B cell-specific Ag CD40. Hydrocortisone (HC) has recently been shown to synergize with IL-4 to induce IgE synthesis in CD5+ chronic lymphocytic leukemia B cells. We show herein that a combination of HC and rIL-4 induces IgE synthesis in highly purified normal peripheral blood B cells. HC and IL-4 acted directly on B cells, because T cells and monocytes were not required for IgE synthesis. IgE induction was shown to occur in surface IgE- B cells isolated by cell sorting. These results suggest that IgE synthesis results from isotype switching, rather than from expansion of a precommitted B cell population. Furthermore, IgE synthesis was induced in sorted CD5- B cells, indicating that the ability to produce IgE in response to HC and IL-4 is not constrained by CD5 expression. Endogenous IL-6 was critical for induction of IgE synthesis by HC and IL-4, because an anti-IL-6 antibody strongly inhibited IgE production. These data suggest that hormones may play an important role in the regulation of IgE synthesis.
Publication
Journal: Psychopharmacology
October/17/1999
Abstract
BACKGROUND
Corticosteroids are elevated in certain neuropsychiatric disorders and this may contribute to the neuropsychological impairments reported in these disorders.
OBJECTIVE
To examine the effects of hydrocortisone on learning, memory and executive function.
METHODS
Hydrocortisone 20 mg was administered twice daily for 10 days to normal male volunteers in a randomized, placebo control, crossover, within-subject design. Learning, memory and executive function were measured using selected subtests from the Cambridge Neuropsychological Test Automated Battery.
RESULTS
Hydrocortisone caused impairments of visuo-spatial memory. These included increased within search errors and impaired use of strategies on the spatial working memory subtest. In addition, administration of hydrocortisone was associated with more errors in the paired associate learning subtest, although no effect was found on the Tower of London. Hydrocortisone speeded response latencies in certain tests (pattern and spatial recognition memory).
CONCLUSIONS
These results indicate that chronic administration of hydrocortisone leads to deficits in certain tests of cognitive function sensitive to frontal lobe dysfunction and may contribute to the cognitive impairment reported in certain neuropsychiatric disorders.
Publication
Journal: Pediatrics
February/6/2006
Abstract
OBJECTIVE
Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency is the most common inherited disorder of adrenal steroid biosynthesis. Patients with the classic form of CAH show androgen excess, with or without salt wasting. There are few studies reporting on higher rates of overweight and obesity among children with CAH. In addition to its role in the regulation of energy balance, leptin is involved in various endocrine and metabolic pathways. In this context, elevated serum leptin levels were reported recently for patients with CAH and were thought to be involved in the development of obesity among these patients. Therefore, the aim of this study was to analyze BMI values, compared with population-based references, for children and adolescents with CAH. Possible contributing factors, such as glucocorticoid therapy, skeletal maturation, birth weight and length, and parental BMI, were correlated with current BMI SD scores (SDS). In addition, the implications of serum leptin levels, corrected for BMI, gender, and Tanner stage, were investigated.
METHODS
We performed a cross-sectional retrospective study of 89 children and adolescents with cah (48 female and 41 male subjects; age: 0.2-17.9 years) who presented in our outpatient department during 1 year. All individuals had classic cah, confirmed with molecular genetic analyses, and received substitution therapy (glucocorticoids and mineralocorticoids, if necessary). The quality of therapy was monitored in follow-up visits every 3 to 6 months, on the basis of clinical presentation and laboratory measurement findings according to current guidelines. We grouped the patients into salt wasting and simple virilizing groups, as well as according to current metabolic control. Leptin levels were measured with a commercial radioimmunoassay and calculated as sds. For statistical analyses, standard parametric and nonparametric methods were used.
RESULTS
The chronologic ages of the children with CAH were between 0.20 and 17.9 years (mean +/- SD: 8.9 +/- 4.6 years). The BMI SDS of the whole group ranged from -2.7 to 4.3 (mean +/- SD: 0.88 +/- 1.3) and was significantly elevated above 0. Fifteen subjects (16.8%) had BMI SDS of >2.0, which indicated a significantly greater frequency of obesity among patients with CAH than expected for the normal population (expected: 2.27%). There was no significant difference in age and BMI between genders and clinical forms (salt wasting versus simple virilizing). BMI SDS was correlated positively with chronologic age. The BMI SDS did not differ significantly between children receiving hydrocortisone, prednisone, or dexamethasone. Hydrocortisone dosages (including equivalent dosages of prednisone and dexamethasone) ranged from 6.2 to 30.1 mg/m2 body surface area (mean +/- SD: 14.7 +/- 4.8 mg/m2 body surface area). Hydrocortisone dosages were correlated positively with BMI SDS. The relative risk of having a BMI SDS of >2.0 was not significantly elevated among children with prednisone/dexamethasone medication, compared with those with hydrocortisone treatment. In contrast to this, fludrocortisone dosage was not correlated with BMI SDS. Bone age delay, as calculated from the difference of bone age and chronologic age, ranged from -2.9 years to 5.6 years (mean +/- SD: 1.11 +/- 1.8 years) and was significantly elevated; it was correlated positively with BMI SDS. The BMI of parents ranged from 17.8 to 39.0 kg/m2 (median: 24.2 kg/m2). Median BMI values did not differ significantly between fathers and mothers. The relative risk for obesity among our children (BMI SDS of >2.0) was significantly elevated for children with obese parents, compared with those with nonobese parents (relative risk: 4.86). There was no significant correlation of birth length, birth weight, or gestational age with BMI SDS. Serum leptin values ranged from 0.10 to 32 microg/L (median: 4.4 microg/L); they were correlated positively with BMI SDS, chronologic age, and Tanner stage. After transformation into leptin concentration SDS values, the median SDS of 0.42 (range: -5.4 to 3.1) did not differ significantly from 0.
CONCLUSIONS
Children and adolescents with CAH have a higher risk of obesity. Glucocorticoid dosage, chronologic age, advanced bone age maturation, and parental obesity contributed to elevated BMI SDS, whereas birth weight and length, serum leptin levels, used glucocorticoid, and fludrocortisone dosage were not associated with obesity. Therefore, children with CAH who become obese should be tightly monitored and should participate concurrently in weight management programs that include obese family members.
Publication
Journal: Journal of Leukocyte Biology
August/28/1996
Abstract
Peripheral blood monocytes are recruited to the inflamed mucosa of inflammatory bowel disease but the specific chemotactic signals responsible for their attraction are not known. Monocyte chemoattractant protein-1 (MCP-1) is a chemokine with potent monocyte attracting and activating properties and the aim of this study was to examine its expression and production in inflammatory bowel disease. In situ hybridization demonstrated mRNA for MCP-1 in macrophages, some of which had been recently recruited from the circulation as demonstrated by their co-expression of the monocyte marker CD 14, as well as in smooth muscle and endothelial cells in inflamed mucosa. Immunohistochemical studies showed a corresponding distribution of MCP-1 protein production by macrophages, smooth muscle, and endothelial cells. By contrast minimal MCP-1 mRNA expression and protein were found in histologically normal mucosa. Macrophages isolated from surgically resected inflammatory bowel disease colons and examined by Northern analysis expressed MCP-1 mRNA significantly more frequently (15/24 vs. 0/19, P< 0.0001) than macrophages from histologically normal mucosa from colon cancer resections. Blood monocytes stimulated by lipopolysaccharide and treated with hydrocortisone, 5-aminosalicylic acid, or cyclosporin A showed reduced MCP-1 expression and production in the presence of these agents. This study demonstrates increased expression of MCP-1 mRNA and protein and cells of origin of MCP-1 in inflamed intestinal mucosa. Together with the demonstrated influence of therapeutic agents on monocyte MCP-1 production the findings suggest a role for MCP-1 in monocyte attraction to the mucosal lesion of inflammatory bowel disease.
Publication
Journal: Molecular Endocrinology
January/3/1996
Abstract
A highly conserved CCAAT/enhancer-binding protein (C/EBP)-binding site centered around -134 relative to the transcription start site in the rat beta-casein gene promoter is capable of interacting specifically with recombinant and mammary gland C/EBP proteins. Western blot analysis indicates that C/EBP levels change dramatically throughout mammary gland development. C/EBP alpha expression is barely detectable in mammary glands from virgin and pregnant animals but is expressed at high levels during lactation and at lower levels during involution. The expression of three C/EBP beta isoforms [the liver-enriched activating proteins (LAPs); and the liver-enriched inhibiting protein (LIP)] is elevated throughout pregnancy, with LIP expression increasing more than 100-fold. Thus, during pregnancy, a low LAP/LIP ratio (< 5) is maintained. C/EBP beta expression decreases at parturition, with LIP diminishing to levels observed in the virgin gland. Therefore, during lactation a more than 100-fold increase in the LAP/LIP ratio is observed. Treatment of the HC11 mammary epithelial cell line with hydrocortisone results in a 10- to 20-fold inhibition of LIP expression, with only minor changes in LAP levels. Therefore, glucocorticoids may impinge upon beta-casein gene expression by altering the ratio of the inhibitory to the activating isoforms of C/EBP beta. Several previously defined casein gene promoter regions capable of conferring hormone and extracellular matrix inducibility to reporter genes in mammary cells are suggested to be composite response elements, containing putative binding sites for the same set of hormonally and developmentally regulated factors: C/EBP, MGF/Stat5, and the glucocorticoid receptor.
Publication
Journal: Annals of Oncology
February/16/2011
Abstract
BACKGROUND
Breast cancer is the leading nonhematologic cause of meningeal carcinomatosis (MC). The aim of this study was to report the outcome of patients diagnosed with breast cancer MC and treated in single institution by a high-dose intrathecal methotrexate (MTX) regimen.
METHODS
Ninety-one patients were diagnosed with breast cancer MC from 2000 to 2007. Intrathecal treatment was MTX 15 mg/day (days 1-5), hydrocortisone acetate (day 1) and oral folinic acid (days 1-5), repeated every 2 weeks. Patients and tumor characteristics were associated with the early clinical and biological outcome and with the overall survival (OS).
RESULTS
The median survival was 4.5 months (range 0-53). In multivariate analysis, adverse prognostic factors at diagnosis were performance status >2 [P = 0.006, response rate (RR) = 0.33 (0.15-0.71)], more than three chemotherapy regimens before MC diagnosis [P = 0.03, RR = 0.40 (0.19-0.93)], negative hormone receptor status [P = 0.02, RR = 0.4 (0.19-0.90)] and high Cyfra 21-1 level [P = 0.048, RR = (0.09-0.99)]. Clinical progression after one cycle and biological response after two cycles were independently associated with OS [P < 0.001, RR = 0.09 (0.02-0.37) and P = 0.003, RR = 3.6 (1.5-8.5), respectively]. We propose a prognostic score in order to define three distinct groups of prognosis.
CONCLUSIONS
MC presents a poor prognosis, but 1-year survival rate was 25%. This score may become a useful tool for treatment decision and clinical trials.
Publication
Journal: The Journal of investigative dermatology
May/18/2008
Abstract
Keloids are benign tumors of the dermis that form during a protracted wound healing process. Susceptibility to keloid formation occurs predominantly in people of African and Asian descent. The key alteration(s) responsible for keloid formation has not been identified and there is no satisfactory treatment for this disorder. The altered regulatory mechanism is limited to dermal wound healing, although several diseases characterized by an exaggerated response to injury are prevalent in individuals of African ancestry. We have observed a complex pattern of phenotypic differences in keloid fibroblasts grown in standard culture medium or induced by hydrocortisone (HC). In this study Affymetrix-based microarray was performed on RNA obtained from fibroblasts cultured from normal scars and keloids grown in the absence and presence of HC. We observed differential regulation of approximately 500 genes of the 38,000 represented on the Affymetrix chip. Of particular interest was increased expression of several IGF-binding and IGF-binding-related proteins and decreased expression of a subset of Wnt pathway inhibitors and multiple IL-1-inducible genes. Increased expression of connective tissue growth factor and insulin-like growth factor binding protein-3 was observed in keloid fibroblasts only in the presence of HC. These findings support a role for multiple fibrosis-related pathways in the pathogenesis of keloids.
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