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Publication
Journal: Journal of Clinical Investigation
September/8/1992
Abstract
We reported that glucagon and phenylephrine decrease hepatocyte GSH by inhibiting gamma-glutamylcysteine synthetase (GCS), the rate-limiting enzyme in GSH synthesis (Lu, S.C., J. Kuhlenkamp, C. Garcia-Ruiz, and N. Kaplowitz. 1991. J. Clin. Invest. 88:260-269). In contrast, we have found that insulin (In, 1 microgram/ml) and hydrocortisone (HC, 50 nM) increased GSH of cultured hepatocytes up to 50-70% (earliest significant change at 6 h) with either methionine or cystine alone as the sole sulfur amino acid in the medium. The effect of In occurred independent of glucose concentration in the medium. Changes in steady-state cellular cysteine levels, cell volume, GSH efflux, or expression of gamma-glutamyl transpeptidase were excluded as possible mechanisms. Both hormones are known to induce cystine/glutamate transport, but this was excluded as the predominant mechanism since the induction in cystine uptake required a lag period of greater than 6 h, and the increase in cell GSH still occurred when cystine uptake was blocked. Assay of GSH synthesis in extracts of detergent-treated cells revealed that In and HC increased the activity of GCS by 45-65% (earliest significant change at 4 h) but not GSH synthetase. In and HC treatment increased the Vmax of GCS by 31-43% with no change in Km. Both the hormone-mediated increase in cell GSH and GCS activity were blocked with either cycloheximide or actinomycin D. Finally, when studied in vivo, streptozotocin-treated diabetic and adrenalectomized rats exhibited lower hepatic GSH levels and GCS activities than respective controls. Both of these abnormalities were prevented with hormone replacement. Thus, both in vitro and in vivo, In and glucocorticoids are required for normal expression of GCS.
Publication
Journal: Journal of Immunology
March/23/1987
Abstract
We previously reported that Mycobacterium bovis (strain BCG) induces continuous I-A expression when injected into BCG-resistant strains of mice. We have extended this observation by showing that Corynebacterium parvum also induces continuous I-A expression by macrophages from BCG-resistant but not BCG-susceptible mice. We have linked continuous expression to BCG resistance by using C.D2Ityr mice, which are congenic with BCG-susceptible BALB/c mice except for genes on a portion of chromosome 1, which contains the gene(s) for BCG resistance. Macrophages from C.D2Ityr mice continuously expressed I-A, whereas macrophages from BALB/c mice transiently expressed I-A. Continuous expression by macrophages from both Bcgr and Bcgs mice could be induced in vitro with rIFN-gamma. However, the continuous expression of I-A by macrophages from Bcgs mice required the continued presence of IFN-gamma, whereas that by Bcgr macrophages did not. The continuous expression of I-A by macrophages from Bcgs mice was also inhibited by hydrocortisone, cyclohexamide, tunicamycin, and monensin, whereas I-A expression by Bcgr macrophages was not affected. The continuous expression of I-A by macrophages from Bcgr mice did not require its continued synthesis. The significance of these findings to the induction of immunity and to antimicrobial resistance are discussed.
Publication
Journal: Journal of Experimental Medicine
November/30/1996
Abstract
1. The effects of normal rabbit serum and of rabbit antiserum to whole foetal mouse tissues, on the isolated limb bones of late foetal mice were studied in organ culture, and the influence of hydrocortisone on these effects was investigated. 2. Unheated normal serum caused slight loss of metachromatic material from the cartilage matrix, and some resorption of both cartilage and bone. 3. In unheated antiserum to foetal mouse tissues, the terminal cartilage was smaller and less metachromatic than in paired controls in normal serum, while osteoclasis was so intense that in many explants the bone had almost disappeared. The amount of necrosis varied with different batches of antiserum. 4. The changes produced by normal serum and antiserum could be largely prevented by heating the sera to 57 degrees C for 45 minutes. 5. The effects could also be inhibited by the addition of hydrocortisone to the unheated sera; as little as 0.1 microg hydrocortisone per ml of medium had a well marked protective action. 6. It is suggested that (a) unheated antiserum causes a release of lysosomal enzymes with consequent breakdown of intercellular material, (b) this release is due to an indirect action on the lysosome via an increased permeability of the cell membrane, (c) hydrocortisone does not affect the antigen-antibody reaction, but inhibits the autolytic changes that normally follow this reaction, possibly by stabilising both the lysosomal and cell membranes.
Publication
Journal: Inflammatory Bowel Diseases
April/15/2008
Abstract
BACKGROUND
Mucosally adherent E. coli are found in inflammatory bowel disease (IBD) and colon cancer. They promote release of the proinflammatory cytokine interleukin-8 (IL-8). We explored mechanisms for this release and its inhibition by drugs.
METHODS
IL-8 release from colon epithelial cells in response to mucosal E. coli isolates from IBD, colon cancer, and controls was characterized at the cellular and molecular level.
RESULTS
IL-8 response of HT29 cells was greater with Crohn's disease (689 +/- 298 [mean +/- SD] pg IL-8/mL at 4 hours, n = 7) and colon cancer isolates (532 +/- 415 pg/mL, n = 14) than with ulcerative colitis (236 +/- 58 pg/mL, n = 6) or control isolates (236 +/- 100 pg/mL, n = 6, P < 0.0001). Bacterial supernatants contained shed flagellin that triggered IL-8 release. For whole bacteria the IL-8 response to E. coli that agglutinate red blood cells (548 +/- 428 pg IL-8/mL, n = 16), a function that correlates with epithelial invasion, was greater than for nonhemagglutinators (281 +/- 253 pg/mL, n = 17; P < 0.0001). This was particularly marked among E. coli that, although flagellate, could not release IL-8 from TLR5-transfected HEK293 cells. IL-8 release was mediated by extracellular-regulated kinase (ERK) and p38 mitogen-activated protein kinase (MAPK) and inhibited by mesalamine, but not hydrocortisone, at therapeutic concentrations.
CONCLUSIONS
Mucosa-associated E. coli shed flagellin that elicits epithelial IL-8 release but this may only become relevant when the mucosal barrier is weakened to expose basolateral TLR5. Adherent and invasive IBD and colon cancer E. coli isolates also elicit a flagellin-independent IL-8 response that may be relevant when the mucosal barrier is intact. The IL-8 release is MAPK-dependent and inhibited by mesalamine.
Publication
Journal: American Journal of Gastroenterology
April/28/1999
Abstract
OBJECTIVE
The aim of this prospective controlled study was to determine whether prophylactic corticosteroids decrease the incidence of post-ERCP pancreatitis.
METHODS
A double-blind comparison of hydrocortisone (100 mg by i.v. infusion immediately before endoscopy) with placebo (sodium chloride administered in the same fashion). A total of 535 patients (286 women and 249 men, with an average age of 58.6 yr) who were scheduled to undergo diagnostic or operative ERCP underwent randomization. Six patients were excluded from the final evaluation for various reasons. The remaining 529 patients, 263 in the hydrocortisone group and 266 in the placebo group, were analyzed. Patients were divided into subgroups with regard to high risk factors for acute pancreatitis after ERCP.
RESULTS
The overall incidence of acute pancreatitis was 5.3% (28 of 529 patients). Procedure-induced pancreatitis occurred in 15 of 263 (5.7%) patients treated with hydrocortisone and in 13 of 266 (4.9%) patients treated with placebo (p = NS). The results of analysis of risk factors for pancreatitis did not evidence any significant difference between the hydrocortisone group and the placebo group.
CONCLUSIONS
Hydrocortisone does not prevent acute pancreatitis after diagnostic or therapeutic ERCP.
Publication
Journal: Molecular medicine today
September/10/1997
Abstract
The secretion of hydrocortisone by the adrenal cortex is crucial in balancing the reaction of the body to injury or stress. In the periphery, hydrocortisone inhibits inflammation, downregulates the immune system and produces many other crucial physiological and metabolic changes. Within the neuroendocrine system, hydrocortisone inhibits the release of adrenocorticotrophic hormone (and other pituitary hormones), thereby governing its own secretion. The manifold actions of hydrocortisone are mediated through induction or repression of many genes but one pathway, mediated by the inducible protein lipocortin 1 (LC-1, also known as annexin 1), mediates several important effects both within the hypothalamo-pituitary-adrenocortical axis itself and in the periphery.
Publication
Journal: Carcinogenesis
September/8/1983
Abstract
We have studied the action of phorbol, 12-myristate, 13-acetate (PMA) on human keratinocytes grown with lethally-irradiated 3T3 cells using medium supplemented with hydrocortisone, cholera toxin and epidermal growth factor. Normal keratinocyte cultures show a heterogeneous response to PMA; 90-93% of the colony-forming cells lose their colony-forming ability and form cornified envelopes when treated for 24 h with doses of 100 nM or less, but the remainder are resistant to doses of 1000 nM. The resistant cells are the precursors of the sensitive ones and heterogeneity is restored to those cells and their progeny after 8 days culture in the absence of PMA. Cultures of 3 squamous cell carcinoma lines, a SV40-transformed human keratinocyte line, and three clones of these lines were found to contain 3-17 times more PMA-resistant keratinocytes than the normal strains, and the size of the PMA-resistant fraction in each line was inversely related to the competence of that line to lose colony-forming efficiency when placed in suspension culture (which is the first detectable change in an ordered programme of events resembling terminal differentiation of the keratinocyte). The number of cells with cornified envelopes in surface cultures of normal human keratinocytes increased from approximately 3% in control cultures to approximately 70% in those treated for 6 days with 100 nM PMA. The transformed human keratinocyte cultures showed a 3-25-fold smaller increase in cornified envelope formation when treated with 100 nM PMA, and the increase in envelope formation by each line when exposed to this dose of PMA was related to the competence of that line to lose cloning efficiency in suspension culture. No relationship was found between the ability of any human keratinocyte strain or line we studied to metabolically inactivate PMA and their resulting response to the compound. The results are discussed in relation to the mechanism of action of PMA as a promoter of epidermal carcinogenesis.
Publication
Journal: Molecular Endocrinology
July/30/2006
Abstract
The sodium/iodide symporter (NIS) mediates a remarkably effective targeted radioiodide therapy in thyroid cancer; this approach is an emerging candidate for treating other cancers that express NIS, whether endogenously or by exogenous gene transfer. Thus far, the only extrathyroidal malignancy known to express functional NIS endogenously is breast cancer. Therapeutic efficacy in thyroid cancer requires that radioiodide uptake be maximized in tumor cells by manipulating well-known regulatory factors of NIS expression in thyroid cells, such as TSH, which stimulates NIS expression via cAMP. Similarly, therapeutic efficacy in breast cancer will likely depend on manipulating NIS regulation in mammary cells, which differs from that in the thyroid. Human breast adenocarcinoma MCF-7 cells modestly express endogenous NIS when treated with all-trans-retinoic acid (tRa). We report here that hydrocortisone and ATP each markedly stimulates tRa-induced NIS protein expression and plasma membrane targeting in MCF-7 cells, leading to at least a 100% increase in iodide uptake. Surprisingly, the adenyl cyclase activator forskolin, which promotes NIS expression in thyroid cells, markedly decreases tRa-induced NIS protein expression in MCF-7 cells. Isobutylmethylxanthine increases tRa-induced NIS expression in MCF-7 cells, probably through a purinergic signaling system independent of isobutylmethylxanthine's action as a phosphodiesterase inhibitor. We also observed that neither iodide, which at high concentrations down-regulates NIS in the thyroid, nor cAMP has a significant effect on NIS expression in MCF-7 cells. Our findings may open new strategies for breast-selective pharmacological modulation of functional NIS expression, thus improving the feasibility of using radioiodide to effectively treat breast cancer.
Publication
Journal: Journal of Investigative Dermatology
November/5/1990
Abstract
The development of growth conditions for human melanocytes from uninvolved skin from vitiligo patients and age-matched normal adults is a prerequisite to understanding the etiology of this pigmentary disorder. By using new growth conditions, pure melanocyte cultures were prepared from normal adults and the pigmented skin of vitiligo donors. Both cell types grew without a lag period and were maintained for more than six months (4-8 passages). The cultures could be expanded from several thousand melanocytes in the original cell suspension to several million cells (2-7 x 10(6] in pure culture. To obtain these results, the current standard conditions for the culture of fetal melanocytes were substantially modified. MEM-S medium was less satisfactory than MCDB-153. Adult normal and vitiligo cells also required the presence of exogenous catalase (20 micrograms/ml) during isolation and primary seeding. Thereafter, this enzyme was not necessary. Melanocytes grew best and gave the highest yields if the concentrations of both calcium (200 microM) and the phorbol ester 12-0-tetradecanoylphorbol-13-acetate (TPA) were low (4-8 nM). Other growth factors included in the MCDB-153 media were bFGF, crude bovine pituitary extract, insulin, transferrin, hydrocortisone, 5% FCS, and the antioxidant alpha-tocopherol. Cholera toxin and isobutylmethylxanthine (IBMX) were omitted from the MCDB-153 growth medium because they slowed down growth even at very low concentrations. The results indicate adult and vitiligo melanocytes can be cultured. Preliminary studies of the normal and vitiligo cells indicate that vitiligo melanocytes retain some of the ultrastructural abnormalities observed in skin even when grown in culture.
Publication
Journal: American Journal of Reproductive Immunology
November/29/1994
Abstract
OBJECTIVE
In general, females have a more active immune response than do males. The effects of female sex hormones on lymphocytes have been studied extensively but their effects on macrophages are poorly understood.
METHODS
In this study, peritoneal macrophages (M phi) obtained from male rats were treated in vitro with estradiol (E2), progesterone (P), testosterone (TS), or hydrocortisone (HC) and their effects on superoxide, hydrogen peroxide, and nitrite release determined.
RESULTS
At concentrations between 10(-10) and 10(-9) M, female and male sex hormones had no significant effect on superoxide release but, at concentrations above or below that range, these hormones stimulated the release of these reactive oxygen intermediates (ROI). In contrast, M phi treated with HC generally exhibited either unaltered or reduced ROI release.
CONCLUSIONS
These findings suggest that female sex hormones regulate ROI release by M phi in a manner not entirely shared by other steroid hormones. At most concentrations used, E2, P, TS, and HC significantly inhibited nitrite release by M phi. However, with 10(-10) M of E2 or 10(-9)M of P, nitrite release by M phi was not affected. In the presence of anti-TNF antibody, the amounts of superoxide and hydrogen peroxide release were moderately reduced but nitrite release was dramatically inhibited. The sensitivity of M phi to variations in the concentrations of female sex hormones may contribute to gender-related differences in the immune response.
Publication
Journal: Journal of Biological Chemistry
April/3/1985
Abstract
The effect of glucocorticoids on sulfated proteoglycan synthesis by rabbit costal chondrocyte cultures exposed to serum-free conditions has been examined. Low density cultures of rabbit costal chondrocytes were maintained on dishes coated with extracellular matrix produced by bovine corneal endothelial cells and exposed to a 9:1 mixture (v/v) of Dulbecco's modified Eagle's medium and Ham's F-12 medium supplemented with transferrin, high density lipoproteins, fibroblast growth factor, and insulin (Medium A). Chondrocytes maintained in the presence of Medium A supplemented with 10(-7) M hydrocortisone reorganized, at confluence, into a homogeneous cartilage-like tissue composed of round cells surrounded by a refractile matrix in which abundant thin collagen fibrils characteristic of type II collagen were observed. The cell ultrastructure and fibrils of the pericellular matrix were similar to those seen in vivo. In contrast, cells maintained in the presence of Medium A alone, once they reached confluence, formed a fibroblastic multilayer and produced thick collagen bundles. The level of 35SO4(2-) incorporated into large cartilage-specific proteoglycans in glucocorticoid-supplemented cultures was 33-fold higher than that of glucocorticoid-free cultures. The level of 35SO4(2-) incorporated into small ubiquitous proteoglycans was only 4-fold higher than that of glucocorticoid-free cultures. On the other hand, the level of [3H]glucosamine incorporated into hyaluronate in glucocorticoid-supplemented cultures was 4.5-fold lower than that of glucocorticoid-free cultures. Within 24 h of their addition to confluent cultures, hydrocortisone or dexamethasone markedly stimulated proteoglycan synthesis. This effect was not mimicked by androgens, estrogens, progesterone, or an inactive form of glucocorticoids such as deoxycorticosterone. This suggests that glucocorticoids have a direct and specific stimulatory effect on cartilage-specific proteoglycan synthesis and are essential for the maintenance of this synthesis in low density chondrocyte cultures.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
June/30/2003
Abstract
The phenotype of congenital adrenal hyperplasia (CAH) varies greatly. The purpose of this study was to optimize diagnosis and follow-up by comparing phenotype with genotype. Sixty-eight patients with CAH due to 21-hydroxylase deficiency were studied by clinical, hormonal, and molecular genetic methods. Patients were classified according to predicted mutation severity: group 0, null mutation (17.6%); group A, homozygous for IVS2 splice mutation or compound heterozygous for IVS2 and null mutations (33.8%); group B, homozygous or compound heterozygous for I172N mutation (14.7%); group C, homozygous or compound heterozygous for V281L or P30L mutations (26.5%); and group D, mutations with unknown enzyme activity (7.4%). All group 0 and A patients had the salt-wasting form, and group C had nonclassical forms. Group B included five salt-wasting and five simple virilizing forms. Groups 0 and A were younger at diagnosis (P < 0.02), and females were more virilized than those in group B. Group B had higher basal plasma 17-hydroxyprogesterone (564 +/- 162 nmol/liter) and testosterone (11 +/- 3 nmol/liter) levels than group C [59 +/- 13 nmol/liter (P < 0.001) and 1.4 +/- 0.2 nmol/liter (P < 0.005), respectively]. Hydrocortisone doses given to groups 0, A, and B were similar at all ages, but lower in group C (P < 0.01). Final height was below target height in classical (n = 16; -2 +/- 0.2 SD score; P < 0.02) and nonclassical (n = 11; -1.2 +/- 0.4 SD score; P < 0.03) forms. The severity of the genetic defects and the clinical-laboratory features are well correlated. Genotyping, combined with neonatal screening and optimal medical and surgical treatment, can help in the management of CAH.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
April/3/1990
Abstract
Thirty late-onset adrenal hyperplasia patients consulting for isolated hirsutism were randomly divided into two groups; group 1 (n = 16) was treated with hydrocortisone in order to suppress androgen adrenal secretion, and group 2 (n = 14) received cyproterone acetate (CPA) antiandrogen therapy to inhibit peripheral androgen activity. The clinical and hormonal effects of each type of treatment were evaluated. Before treatment, the clinical and hormonal profiles of the two patient groups did not differ significantly. Excellent clinical evolution in terms of the regression of hirsutism was observed in the CPA-treated patients (54% decrease in the clinical score in 1 yr), in contrast with the slight decrease in hirsutism (26%) after hydrocortisone treatment. In hydrocortisone-treated patients, plasma androgen decreased to normal levels: testosterone from 3.05 +/- 1.45 to 1.46 +/- 0.42 nmol/L and delta 4-androstenedione from 13.6 +/- 4.1 to 6.33 +/- 1.47 nmol/L. Conversely, in CPA-treated patients, only a slight decrease in testosterone from 2.98 +/- 1.98 to 2.29 +/- 0.64 nmol/L and in delta 4-androstenedione from 12.9 +/- 5.9 to 9.86 +/- 2.23 nmol/L was observed. This slight decrease in plasma androgens contrasts with the rapid clinical improvement after CPA. These results emphasize the importance of peripheral receptivity to androgens in the clinical expression of hyperandrogenism. Moreover, they indicate that peripheral antiandrogen therapy may be more appropriate in late-onset adrenal hyperplasia patients than conventional adrenal inhibition using cortisone therapy.
Publication
Journal: Drugs
January/3/1990
Abstract
Mesalazine (5-aminosalicylic acid; mesalamine), the active moiety of sulphasalazine (salazosulfapyridine), is available in specially formulated oral and rectal forms for the treatment of active ulcerative colitis of mild to moderate severity and for maintenance therapy during disease remission. Tablets or capsules coated with acrylic-based resin and tablets containing microgranules coated with ethylcellulose deliver mesalazine to the distal small intestine and colon, thus avoiding the need for the carrier, sulphapyridine, which is responsible for many of the adverse effects associated with sulphasalazine. Since mesalazine is released in the small intestine from some coated preparations in contrast to sulphasalazine, these oral formulations have therapeutic potential in Crohn's disease. A limited number of therapeutic trials suggest that orally administered mesalazine 1.5 to 2.4g daily is of similar efficacy to sulphasalazine 2 to 3g daily in patients with mild to moderate ulcerative colitis. The efficacy of mesalazine enemas has been more widely investigated, a dose of 1 to 4g once daily being consistently more effective than placebo and apparently similar to enemas of prednisone 25mg or oral sulphasalazine 3g. Initial results suggest that mesalazine 4g enemas may be more effective than those containing hydrocortisone 100mg. Mesalazine and sulphasalazine in approximately equivalent oral dosages are similarly effective in maintaining remission in ulcerative colitis. Orally administered coated mesalazine is generally well tolerated by about 85% of patients allergic to or intolerant of sulphasalazine, the remainder experiencing similar reactions to both drugs. Adverse effects of mesalazine enemas are confined to local irritation and effects resulting from enema-tip insertion. Thus, orally administered coated mesalazine is a suitable alternative to sulphasalazine in the treatment of patients with mild to moderate active distal ulcerative colitis and for maintaining remission particularly in patients allergic to or intolerant of sulphasalazine. In patients who find enema therapy acceptable, mesalazine enemas are effective and well tolerated.
Publication
Journal: Journal of Immunology
October/27/1975
Abstract
At pharmacological levels, glucocorticosteroids inhibited two antigen-induced lymphocyte functions, in vitro proliferation and lymphokine synthesis. Lymphocyte production of both macrophage chemotactic factor (CTX) and macrophage inhibition factor (MIF) were decreased in the presence of hydrocortisone. The corticosteroid also blocked the action of MIF on macrophages but did not interfere with the action of CTX on macrophages. Thus, steroids can suppress the immune response at two different stages: by blocking lymphocyte activation and mediator synthesis and also by interfering with the interaction of certain effector molecules with their target cells. Furthermore, these findings suggested that MIF and CTX have distinct mechanisms of action on the effector macrophages, one being sensitive and one resistant to steroids.
Publication
Journal: Journal of Urology
August/15/2002
Abstract
OBJECTIVE
High-dose (400 mg.) oral ketoconazole 3 times daily with replacement doses of hydrocortisone has become a standard treatment option for patients with advanced prostate cancer which progresses after androgen deprivation. However, toxicity can hinder the ability to deliver treatment and the cost of the regimen can be substantial. Therefore, a prospective phase II study was conducted to assess the efficacy and safety of a regimen of low dose (200 mg.) oral ketoconazole 3 times daily with replacement doses of hydrocortisone in men with androgen independent prostate cancer.
METHODS
The study included 28 patients with progressive prostate cancer despite anorchid levels of testosterone and ongoing testicular androgen suppression. Treatment consisted of low dose ketoconazole and replacement doses of oral hydrocortisone (20 mg. every morning and 10 mg. at bedtime). At the time of disease progression patients were treated with high dose ketoconazole and continued on the same dose of hydrocortisone. Adrenal androgen levels were measured, and baseline and followup levels correlated with clinical outcome.
RESULTS
Overall, 13 (46%) of 28 patients had a prostate specific antigen decrease of more than 50% (95% confidence interval 27.5% to 66.1%). Median duration of prostate specific antigen decrease for all responders was 30+ weeks and 5 patients continue to exhibit a response, ranging from 36+ to 53+ weeks. In general, therapy was well tolerated. There were no grade 4 toxicities. Grade 3 toxicities included hepatotoxicity in 1 patient and depression in 2. The most common toxicities were nausea (29% grades 1 and 2), dry skin (18% grade 1) and fatigue (14% grade 1). Four (14%) patients discontinued low dose ketoconazole due to toxicities. Of the 16 patients who received high dose ketoconazole after disease progression with low dose ketoconazole, 3 were removed from treatment due to toxicity and no patient responded to high dose ketoconazole. There was no difference in the distribution of pretreatment endocrine values between responders and nonresponders, and the magnitude of change in adrenal androgen levels was not associated with response to therapy, although a potential association could easily have been missed due to small sample size.
CONCLUSIONS
The regimen of low dose ketoconazole with replacement doses of hydrocortisone is well tolerated and has moderate activity in patients with progressive androgen independent prostate cancer.
Publication
Journal: Journal of Bone and Mineral Research
October/26/1988
Abstract
The effect of a preincubation period, in basic medium or in medium with inhibitors of prostaglandin biosynthesis, on the response to different stimulators of bone resorption has been studied in an organ culture system using calvarial bones from neonatal mice. Bone resorption was assessed either by the release of 45Ca or by the release of 3H from [3H]-proline labeled bones. Preincubated bones were cultured for 18-24 hr in medium, with and without indomethacin, hydrocortisone, and dexamethasone, and then extensively washed before being transferred to culture medium containing different stimulators of bone resorption. Preincubation in medium containing indomethacin or corticosteroids resulted in an increased response to parathyroid hormone (PTH), prostaglandin E2 (PGE2), 1-alpha-hydroxyvitamin-D3 and thrombin as compared to the response in bones which were exposed to the stimulants directly after dissection. Preincubation in basic medium did not enhance the subsequent response to PTH. By using a preincubation period in indomethacin, the dose-response curves for the stimulatory effect of PTH and PGE2 on mineral mobilization could be sensitized as compared to the curves obtained with fresh bones. Thus, the concentration of agonists causing 50% stimulation of 45Ca release was decreased by a factor of 10. The threshold for actions of PTH and PGE2 on 45Ca release was 0.01-0.03 and 1-3 nmol/l, respectively.
Authors
Publication
Journal: Antimicrobial Agents and Chemotherapy
November/8/1998
Abstract
Outbred ICR mice were immune suppressed either with hydrocortisone or with 5-fluorouracil and were infected intranasally with Aspergillus fumigatus. Beginning 3 days before infection some groups of mice were given recombinant human granulocyte colony-stimulating factor (G-CSF), SCH56592 (an antifungal triazole), or both. Corticosteroid-pretreated mice responded to SCH56592 and had reduced counts in lung tissue and prolonged survival. In these mice, G-CSF strongly antagonized the antifungal activity of SCH56592. Animals treated with both agents developed large lung abscesses with polymorphonuclear leukocytes and large amounts of Aspergillus. In contrast, mice made neutropenic with 5-fluorouracil and then infected with A. fumigatus conidia benefited from either G-CSF or triazoles, and the effect of the combination was additive rather than antagonistic. Host predisposing factors contribute in different ways to the outcome of growth factor therapy in aspergillosis.
Publication
Journal: Journal of Immunology
June/27/1978
Abstract
Spleen cells from mice bearing methylcholanthrene-induced fibrosarcomas impaired mitogen responses of normal syngeneic lymphocytes. Nylon wool column and other depletion techniques were utilized to characterize the cellular source of suppressive activity in tumor-bearing host (TBH) spleens. Evidence is presented for two distinct suppressor cell systems operating in the spleens, but not lymph nodes, of BALB/c mice bearing transplanted tumors. Spleens from TBH were shown to have greatly increased numbers of macrophages over their normal counterparts. TBH macrophages were observed to have suppressive activity at low in vitro concentrations. Anti-Thy 1 serum treatment of TBH macrophages abrogated low dose inhibition but not suppression due to high numbers of macrophages. No functional difference was detected between anti-Thy 1 serum-treated TBH and normal splenic macrophages. In a macrophage-depleted culture system, mildly nylon wool adherent, anti-Thy 1 serum, and hydrocortisone succinate-sensitive suppressor cells could be detected. Soluble supernatant products of TBH spleen and thymus cells were also found to inhibit in vitro mitogen responses, whereas TBH macrophages and lymph node cells demonstrated no soluble suppressive activity. The major source of soluble inhibitor of DNA synthesis (IDS) seems to be an anti-Thy 1 serum, hydrocortisone-sensitive population.
Publication
Journal: Gastrointestinal Endoscopy
April/29/2002
Abstract
BACKGROUND
Octreotide is a potent inhibitor of pancreatic secretion, and corticosteroids suppress humoral and cellular activity. Both agents may reduce the frequency of post-ERCP pancreatitis. The aim of this study was to determine the effectiveness of octreotide and hydrocortisone in preventing post-ERCP pancreatitis.
METHODS
Three hundred fifty-four patients were entered in to a multicenter randomized controlled trial of 100 microg subcutaneous octreotide (Group 1) versus 100 mg intravenous hydrocortisone (Group 2) versus normal saline solution as placebo (Group 3). All medications were administered approximately 30 minutes before the procedure. Patients were assessed clinically and serum amylase was also measured before the procedure and 3, 12, and 24 hours after the procedure.
RESULTS
Three hundred forty patients were included in the analysis. Pancreatitis was observed in 11 of 112 patients (9.8%) in Group 1, 8 of 113 (7.1%) patients in Group 2, and in 15 of 115 (13.0%) patients in Group 3 (p = 0.32). The mean length of hospitalization in days was similar in all 3 groups: mean (SD) for Groups 1, 2, and 3 were, respectively, 3.6 (1.6) versus 2.9 (0.6) versus 4.3 (1.8) (p = 0.13). Multivariate logistic regression analysis showed that number of pancreatic injections, suspicion of sphincter dysfunction, therapeutic procedure, and age were risk factors for pancreatitis.
CONCLUSIONS
The results of this trial indicate that octreotide and hydrocortisone do not prevent ERCP-induced pancreatitis.
Publication
Journal: Archives of Disease in Childhood
May/25/1981
Abstract
In 11 children aged between 2 and 17 years with (nonsalt-losing) congenital adrenal hyperplasia (21-hydroxylase deficiency) blood was drawn at 90-minute intervals during a 24-hour period and levels of 17-hydroxyprogesterone, testosterone, and cortisol were measured. Levels of 17-ketosteroids and pregnanetriol were measured too in 24-hour urine samples. These measurements were taken under different regimens of treatment and after interruption of treatment. Cortisol level rose and fell rapidly after administered corticosteroid, and reached unphysiologically high levels. Testosterone levels showed pronounced variations but stayed in the normal range for most of the time even in untreated patients; thus testosterone provides a poor control parameter. Levels of 17-hydroxyprogesterone showed extreme fluctuations and very high peak levels in untreated patients; standard treatment with two or three daily doses of corticosteroids did not prevent a pronounced rise in its level after midnight. After the first morning dose of hydrocortisone a very steep fall was observed. The 24-hour pregnanetriol excretion correlated well with the corresponding total integrated 17-hydroxyprogesterone area. It is concluded that single 17-hydroxyprogesterone values are unlikely to give adequate information about the quality of treatment.
Publication
Journal: Surgical neurology
November/4/2007
Abstract
BACKGROUND
Hyponatremia is a frequently observed electrolyte abnormality in patients with central nervous system disease. Several mechanisms, such as SIADH, hypopituitarism, and CSWS, have been proposed with varied incidences among several studies. We attempted to clarify the incidence and mechanism of hyponatremia for each type of TBI. We also assessed the efficacy of sodium supplementation and retention therapy. For sodium retention therapy, hydrocortisone was administered, expecting its mineralocorticoid effect, when the hyponatremia was associated with excess natriuresis.
METHODS
Retrospective analysis of 298 patients with TBI between January 2003 and December 2004 was performed. The incidence, background, clinical data, and outcome were evaluated.
RESULTS
Of the 298 patients, 50 (16.8%) presented hyponatremia during the time course. Hyponatremia was associated with longer hospital stay (P < .001) and bad outcome (P = .02). Among these 50 patients, 37 recovered from the hyponatremia with simple sodium supplementation. The remaining 13 patients presented massive natriuresis and required additional sodium retention therapy. Hydrocortisone statistically reduced the amount of sodium excretion (P = .002) and returned the serum sodium level to a normal value.
CONCLUSIONS
A high rate of hyponatremia after TBI was observed. Further studies are required to establish the precise mechanism of hyponatremia after TBI. Clear definition of CSWS is required to avoid confusion of the pathophysiology that causes hyponatremia. Hydrocortisone was useful to prevent excess natriuresis.
Publication
Journal: Journal of Clinical Investigation
March/12/1982
Abstract
The direct effects of steroid hormones on the production of immunoglobulins and DNA synthesis by human T and B lymphocytes was evaluated in cultures of peripheral blood mononuclear cells. As detected by a reverse hemolytic plaque assay, the addition of 0.1 mM to 10 nM hydrocortisone to lymphocytes in culture in the absence of other stimulants or mitogens, resulted in the dramatic induction of immunoglobulin production with responses comparable to those seen in similar cultures stimulated with pokeweed mitogen. Steroid-stimulated immunoglobulin production was first seen after 48 h and peaked at 8-10 d of culture. The production of IgG, IgA, and IgM was induced following incubation with steroid. Glucocorticoids, but not estrogens or androgens, were capable of mediating this effect, and only compounds with affinity for the glucocorticoid receptor were active. The induction of immunoglobulin production was dependent on both T cells and monocytes; cultures depleted of either cell type did not produce immunoglobulin when stimulated with glucocorticoid hormones. Proliferation of B cells or T cells could not be detected by [3H]thymidine incorporation or total cell recovery from steroid-stimulated cultures, even though such cultures demonstrated marked increases in immunoglobulin production. The mechanism responsible for this functional maturation of B cells to become high rate immunoglobulin producing cells is as yet undefined, although it appears to involve more than merely steroid mediated inactivation of suppressor T cells.
Publication
Journal: The American journal of physiology
November/18/1987
Abstract
Transmural electrical stimulation of isolated ring segments of the rabbit carotid artery caused frequency-dependent contractions; these were blocked by tetrodotoxin or prazosin. Mechanical or chemical removal of the endothelium markedly augmented responses to electrical stimulation. Inhibition of norepinephrine uptake and metabolism with cocaine, hydrocortisone, and pargyline increased contractions in rings with endothelium more than those without endothelium, but responses remained greater in rings denuded of endothelium. Methylene blue, an inhibitor of guanylate cyclase, enhanced responses to electrical stimulation of rings with intact endothelium only. Combined inhibition of guanylate cyclase and norepinephrine disposition increased the contractions and abolished the difference between the responses of rings with and without endothelium. In a perfusion-cascade system, the perfusate of donor segments with endothelium relaxed a bioassay ring without endothelium. Electrical stimulation of the segment caused no further relaxation of the bioassay ring. However, contractions caused by electrically stimulating the bioassay ring were depressed during superfusion with the perfusate of segments with, but not without, endothelium, indicating that vasodilators spontaneously released from the endothelium inhibit responses to nerve stimulation. These observations suggest that inhibition by the endothelium of the response to adrenergic nerve stimulation results from 1) spontaneous release of endothelium-derived vasodilators and 2) disposition of norepinephrine by the endothelial cells.
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