The effects of intramuscularly and orally administered medroxyprogesterone acetate on cytochrome P450 3A4 (CYP3A4) activity were investigated in twelve postmenopausal women in a randomized, crossover study. Unbound prednisolone clearance and the erythromycin breath test were used as markers of CYP3A4 activity. After 2 months of intramuscular progestin therapy, unbound prednisolone clearance increased by 25% in five of six subjects. Similarly, after intramuscular progestin therapy, results from the erythromycin breath test showed a 23% mean increase in CYP3A4 activity. In contrast, 2 months of oral progestin therapy had no effect on prednisolone pharmacokinetics or erythromycin metabolism. These results suggest that parenterally but not orally administered progestins may induce or activate the CYP3A4 enzyme system, leading to an increased metabolism of many CYP3A4 substrates.

The effects of a topically applied corticosteroid, budesonide, on the expression of glucocorticoid receptor (GR) mRNA and regulation of pro-inflammatory cytokine patterns in patients with nasal polyps were evaluated. All patients were eligible for surgical polypectomy, and a majority of them had been treated with nasal steroids. Patients were given 400 microg b.i.d. (group A, n = 11), 200 microg b.i.d. (group B, n = 10), or no treatment (group C, n = 15) during two months before polypectomy. Morning serum cortisol was analyzed on the day of surgery. Surgically removed polyps were taken for analysis of GR mRNA expression by solution hybridization. Remaining tissue was cryostat-sectioned, whereafter quantification of the cytokines interleukin 1beta, interleukin 2, interleukin 4, interleukin 5, interleukin 6, interleukin 10, tumor necrosis factor alpha, and interferon gamma was made by immunohistochemistry and digitized image analysis. No significant differences among the three groups were found for any of the parameters investigated.

In vitro studies suggest that glucocorticoids may counteract beta-agonist-induced desensitization of beta-adrenoceptors by actions at the transcriptional level, but the clinical relevance of such findings is not clear. Oral terbutaline treatment decreases beta-adrenoceptor sensitivity in alveolar macrophages in vivo. This effect is not counteracted by inhaled or orally taken steroids. We therefore examined whether inhaled terbutaline elicited a similar effect on beta(2)-adrenoceptor sensitivity in alveolar macrophages, and if co-treatment with an inhaled steroid, budesonide, would prevent such down-regulation. Bronchoalveolar lavage (BAL) and lung function tests, including bronchodilator responses to inhaled terbutaline, were performed before and after 2 weeks of regular inhalation of terbutaline, 0.5 mg three times daily, and budesonide, 400 microg twice daily, or placebo, in 24 healthy volunteers. Four untreated subjects served as controls. A marked, approx. 90%, decrease in isoprenaline-induced cAMP accumulation in alveolar macrophages was found in both treatment groups after 2 weeks, with no difference between placebo and budesonide (P = 0.45). In the untreated control group, cAMP responses to both isoprenaline and prostaglandin E(1) tended to be lower on the second occasion. A limited, non-specific desensitization of adenylate cyclase activity thus contributed to the marked desensitization elicited by terbutaline inhalations. The bronchodilator response to inhaled terbutaline did not change after treatment in any of the three groups (F = 0.9, P = 0.50). In conclusion, inhalation of a beta-agonist induced marked down-regulation of beta(2)-adrenoceptor sensitivity in alveolar macrophages in vivo without influencing the bronchodilator response to a beta(2)-agonist in healthy subjects. Co-treatment with an inhaled steroid failed to counteract the desensitization of alveolar macrophage beta(2)-adrenoceptors.

Mycophenolic acid is reported to provide effective immunosuppression by inhibiting inosine monophosphate dehydrogenase. In an attempt to monitor the biological effects of long-term therapy with mycophenolate mofetil, we measured levels of guanosine 5' triphosphate and adenosine 5' triphosphate in red blood cells (RBCs) of patients after heart transplantations.

This study evaluated the effects of RRR-alpha-tocopherol (500 IU/day, 8 days) on in vivo cytokine response and cytoplasmic expression of inducible nitric oxide synthase (iNOS) and the antioxidant stress protein heme oxygenase-1 (HO-1) in human leukocytes after exhaustive exercise. Thirteen men were investigated in a double-blind, placebo-controlled, cross-over study with a wash-out period of 28 days. The exercise procedure consisted of an incremental treadmill test followed by a continuous run until exhaustion at 110% of the individual anaerobic threshold (total duration 28.5 +/- 0.8 min). HO-1 and iNOS protein were assessed in mono- (M), lympho-, and granulocytes (G) using flow cytometry. Plasma interleukin-6 (IL-6) and IL-8 were measured by ELISA. IL-6 rose significantly whereas IL-8 did not exhibit significant changes after exercise. Changes of IL-6 were not affected by RRR-alpha-tocopherol. Exercise induced an increase of iNOS protein primarily in M and G. A small, but significant, increase of HO-1 protein was measured in M and G. RRR-alpha-Tocopherol did not show any significant effects on cytoplasmic expression of iNOS and HO-1 at rest and after exercise. In conclusion, exhaustive exercise induces expression of iNOS and HO-1 in human leukocytes by a mechanism that is not sensitive to RRR-alpha-tocopherol supplementation.

Comparison of the efficacy of differing starter doses of recombinant follicle stimulating hormone (rFSH) for IVF and intracytoplasmic sperm injection cycles when the treatment is administered both subcutaneously and intramuscularly.

To investigate whether the expression of uncoupling proteins (UCP2 and UCP3) was affected by a very low calorie diet (VLCD) and growth hormone (GH) treatment for 4 weeks.

Mutations in the HSD11B2 gene encoding the kidney (11-HSD2) isozyme of 11beta-hydroxysteroid dehydrogenase cause apparent mineralocorticoid excess, a form of familial hypertension. Because the hypertension associated with AME is of the salt-sensitive type, it seemed possible that decreases in 11-HSD2 activity might be associated with salt sensitivity. To examine this, Italians with mild hypertension underwent a protocol consisting of a rapid intravenous saline infusion and subsequent furosemide diuresis. To determine whether there were genetic associations between HSD11B2 and salt sensitivity, 198 Italians were genotyped for a CA repeat polymorphism (11 alleles) in the first intron. Increased differences in mean arterial pressure between the sodium loaded and depleted states were correlated with shorter CA repeat length (R=0.214, P=0. 0025). The effect behaved as a recessive trait. This suggested that decreased HSD11B2 expression was associated with shorter CA repeat length. Furthermore, activity of renal 11-HSD2 as measured by an increase in the ratio of urinary-free cortisol/urinary-free cortisone was lower in 33 salt-sensitive subjects (urinary-free cortisol/urinary-free cortisone 0.89+/-0.04 [mean+/-SE]) compared with 34 salt-resistant subjects (0.71+/-0.04, P<0.001). However, when minigenes containing either 14 or 23 CA repeats were transfected into rabbit or human kidney cortical collecting duct cells, the construct with 14 repeats was instead expressed at levels 50% higher than those of the construct with 23 repeats, as determined by reverse transcription-polymerase chain reaction. We conclude that polymorphisms in HSD11B2 and decreased 11-HSD2 activity are associated with sensitivity to sodium loading, but a functional explanation for these associations remains to be elucidated.

The effect of intravenous administration of lipid emulsions enriched with omega-3 (n3) and omega-6 (n6) fatty acids on equine monocyte phospholipid fatty acid composition and the synthesis of inflammatory mediators in vitro was evaluated. In a randomized crossover design, horses were infused intravenously with 20% lipid emulsions containing n3 or n6 fatty acids. Monocytes were isolated from the horses before and 0 h, 8 h, 24 h, and 7 days after lipid infusion. Monocyte fatty acid analysis demonstrated incorporation of the parenteral n3 and n6 fatty acids in monocyte phospholipids immediately after infusion, with changes in the fatty acid composition persisting for up to 7 days after infusion. In vitro production of the inflammatory mediators thromboxane B2/thromboxane B3 (TXB(2/3)) and tumor necrosis factor-alpha (TNFalpha) by peripheral blood monocytes was diminished by n3 lipid infusion and was unchanged or increased by n6 lipid infusion. The results of this study demonstrate that short-term infusions of n3 and n6 fatty acid-enriched lipid emulsions alter the fatty acid composition of equine monocyte phospholipids and modify the inflammatory response of these cells in vitro. These results also support further investigation into the use of parenteral n3 fatty acids as part of the supportive therapy of patients with multiple organ dysfunction (MODS) or systemic inflammatory response syndrome (SIRS).

The in vivo effects of beta-adrenergic receptor (betaAR) agonists given chronically by metered-dose inhaler (MDI) on the molecular components of the beta-adrenoceptor system expressed by human respiratory cells are poorly understood. This study examined the effects of inhaled albuterol (180 microg four times daily for 7 days) on betaAR function of airway epithelial cells (AECs) and alveolar macrophages (AMs) freshly isolated from 10 normal subjects. Responses were related to beta2AR genotype in codons 16 and 27, regions which affect chronic responses to beta2-agonists. In AEC, betaAR density and adenosine cyclic 3',5'-phosphate (cAMP) production in response to isoproterenol (ISO) were significantly lower in the albuterol versus placebo treatment arm (p < 0.01 for both). Moreover, in AEC, albuterol treatment increased betaAR-kinase (betaARK) protein immunoreactivity. In contrast, in AM, albuterol tended to decrease betaAR density and cAMP production but changes did not achieve statistical significance (p > 0.20 for both) and had no effect on betaARK immunoreactivity. Changes in betaAR density occurred in all subjects but tended to be greater in subjects with the glycine 16 genotype. In cultured cells exposed to equal concentrations of beta-agonist in vitro, the magnitude of betaAR down-regulation (p < 0.05) and cAMP densensitization (p < 0.05) was greater in AEC than AM. These results indicate that albuterol taken by inhalation in a therapeutically relevant dose for 1 week produces betaAR down-regulation, densensitizes the cAMP response of airway epithelial cells to a beta2-adrenergic agonist, and increases betaARK immunoreactivity. Greater densensitization of AEC than AM in response to chronic albuterol inhalation likely reflects cell type-specific responses.

Imiquimod (IQ) has been successfully used in treatment of genital warts. In clinical settings, patients responded well but wart reduction rates varied. Our aim was to find a correlation between clinical responses and pretreatment (constitutive) levels of genes that might be involved in the molecular action of IQ. Since IQ is a cytokine inducer, we analyzed levels of expression of genes of the JAK/STAT signaling pathway and their inhibitors as well as interferon response factors (IRFs) in pretreatment biopsy specimens from complete responders (99 to 100% wart reduction rate) versus incomplete responders (75 to 92% wart reduction rate) by reverse transcription-PCR. We found that mRNA levels of signal transducer and activator of transcription 1 (STAT1) and IRF1 were higher in complete responders than in incomplete responders. Incomplete responders expressed larger amounts of STAT3, IRF2, and protein inhibitor of activated STAT1 (PIAS1) mRNAs compared to complete responders before IQ treatment. We hypothesize that high-level expression of STAT1 and IRF1 is advantageous for a better IQ response. The observed differences in constitutive mRNA levels of these genes may be the consequence of alterations in cellular differentiation and/or variable expression of endogenous interferons. Previous in vitro studies showed that keratinocyte differentiation coordinates the balance between positive and negative signals along the JAK/STAT pathway by regulating the IRF1:IRF2 and STAT1:PIAS1 ratios and thus affecting induction of IQ-inducible genes. Specifically, differentiation supports constitutive expression of STAT1 and IRF1 mRNAs but not expression of IRF2 and PIAS1. Our data are in good agreement with studies that showed the importance of STAT1 in cytokine induction and activation of interferon-responsive genes by IQ.

The effect and clinical significance of tolcapone withdrawal on erythrocyte catechol-O-methyltransferase (COMT) activity, levodopa pharmacokinetics, and levodopa requirements were investigated in 59 patients with fluctuating parkinsonism who were randomized to receive placebo or tolcapone 100 or 200 mg three times daily for 6 weeks. Tolcapone withdrawal caused a transient elevation in COMT activity by 64% in patients receiving 100 mg three times daily and by 128% in those receiving 200 mg three times daily at approximately 1-2 weeks after discontinuation of drug. Thereafter, COMT activity was declining but did not reach baseline values by the 12-week study endpoint. However, this had no effect on plasma levodopa and 3-O-methyldopa (3-OMD) concentrations or on levodopa requirements. During treatment, tolcapone increased "on" time and decreased "off" time; after discontinuation of study medication and levodopa dose adjustment, on and off times were similar to baseline. Withdrawal was generally well tolerated; no patients withdrew from the trial during the posttreatment period, and no serious adverse events were observed. In conclusion, the transient increase in erythrocyte COMT activity observed after discontinuation oftolcapone is not associated with changes in peripheral levodopa metabolism and therefore has no significant clinical consequences in terms of levodopa requirements, clinical symptoms, or adverse events.

VML 295 (LY 293111) is a potent and specific leukotriene(4) receptor antagonist. It has previously been shown in human volunteers that VML 295 at a dosage of 48 mg twice daily inhibits the ex vivo leukotriene B(4) (LTB(4))-induced upregulation of CD11b on peripheral blood neutrophils. A clear dose-response relatinship was shown. In addition, VML 295 inhibits various inflammatory aspects resulting from LTB(4) challenge of the skin, again showing a dose-response relationship. In view of the large variation in the elimination half-life of VML 295 (25-88.5 h) in individual human subjects, the present pharmacological study was designed to provide information on the pharmacodynamics of the drug by the assessment of VML 295 plasma concentrations, ex vivo LTB(4)-induced CD11b upregulation of neutrophils, neutrophil accumulation in the skin following epicutaneous application of LTB(4) and epidermal regeneration following standardized surface trauma. A group of 36 healthy volunteers were treated in a double-blind study with VML 295 at 200 mg twice daily, VML 295 at 200 mg once daily or placebo for 7 days. Before treatment, at the end of treatment and following discontinuation of treatment, VML 295 plasma concentrations and CD11b upregulation of blood neutrophils were assessed. In 18 subjects, the effects of the three treatments on LTB(4)-induced inflammatory were assessed before and at the end of treatment, and in the remaining 18 subjects the effects of these treatments on epidermal regeneration were assessed similarly. VML 295 at 200 mg either twice or once daily has a profound inhibitory effect on ex vivo LTB(4)-induced CD11b upregulation of blood neutrophils, LTB(4)-induced neutrophil accumulation in the skin, trauma-induced hyperproliferation of the epidermis and regenerative keratinization. The twice daily dose schedule was significantly more effective than the once daily regimen in reducing ex vivo CD11b stimulation of neutrophils, in blood samples collected 24 h after discontinuation of VML 295 treatment. The twice daily schedule tended to be more efficient in skin biopsies, although this difference was not statistically significant in the number of subjects investigated. A plasma concentration of 100 ng/ml proved to be the threshold for these effects. The profound biological effects, both systemically and cutaneously, as well as the safety profile, make VML 295 a promising drug for skin disorders characterized by epidermal proliferation and neutrophil accumulation.

Forty-two healthy subjects were randomized in a parallel three-group design trial to investigate potential electrocardiographic and pharmacokinetic interactions between the new antimalarial co-artemether, a combination of artemether and lumefantrine (both of which are predominantly metabolized through CYP3A4), and mefloquine, another antimalarial described as a substrate (and possible inhibitor) of CYP3A4. Subjects were assigned to one of the three possible treatment groups (i.e., co-artemether alone or mefloquine alone or the combination of both). The dosage was 1000 mg mefloquine (divided into three doses over 12 h) followed 12 h later by six applications of co-artemether (40 mg artemether+480 mg lumefantrine each) over 60 h. The study medications were generally well tolerated after all treatments. Concomitant administration with mefloquine caused statistically significant lower (around 30-40%) plasma concentrations of lumefantrine than when co-artemether was administered alone. Even if important, this decrease in lumefantrine exposure was considered unlikely to impact clinical efficacy given the wide therapeutic index of co-artemether and the usual high variability in lumefantrine plasma levels, mostly and more importantly influenced by food intake. However, patients should be encouraged to eat at dosing times to compensate for this decreased bioavailability. The pharmacokinetics of artemether, DHA or mefloquine were not affected. Artemether concentrations significantly decreased over doses, independently of mefloquine co-administration, while DHA concentrations slightly (not significantly) increased. Therefore, no clinically relevant risks due to pharmacokinetic drug-drug interaction are expected at the enzymatic level following co-administration of co-artemether with CYP3A4 substrates with similar affinity to that of mefloquine.

Plasma levels of circulating adhesion molecules (AMs) are increased in a number of inflammatory and cardiovascular disorders. Yet the mechanisms regulating the physiologic levels of soluble AMs are largely unknown. It has recently been postulated that glucocorticoids may exert their anti-inflammatory actions partially through the inhibition of cytokine-stimulated expression of E-selectin and intercellular adhesion molecule (ICAM-1). However, it remains controversial whether glucocorticoids affect the basal expression of AMs on resting cells. We have thus evaluated the effects of glucocorticoids by infusing therapeutic doses of dexamethasone (0.04 mg/kg and 1.0 mg/kg twice a day for 2 days) or placebo on plasma levels of circulating E-selectin (cE-selectin), soluble thrombomodulin (sTM), circulating ICAM-1 (cICAM-1), and circulating vascular cell adhesion molecule (cVCAM-1) in 9 healthy men. Plasma was obtained before infusion at 24 and 48 hours. Compared with baseline, levels of cE-selectin decreased by 16% and 22% with the lower and the higher doses, respectively, at 48 hours (P = .007), whereas sTM was unchanged. Both doses of dexamethasone reduced cICAM-1 by about 15% at 48 hours (P = .007), but there were no changes in cVCAM. Dexamethasone time-dependently decreases plasma levels of cE-selectin and cICAM-1 in healthy men. This demonstrates that a glucocorticoid-sensitive mechanism specifically down-regulates normal plasma levels of cE-selectin and cICAM-1 in healthy subjects, which could thus reflect minor baseline inflammation.

In this study, the roles of oestrogen and progesterone in the regulation of oxytocin gene expression in equine endometrium were examined. Anoestrous mares (n=19) were assigned randomly to one of the following treatment groups: control (vehicle control for 1 day; n=3); progesterone (250 mg progesterone per day for 6 days; n=4); oestradiol (5 mg beta-oestradiol 17-valerate per day for 6 days; n=4); oestradiol plus short duration progesterone (5 mg beta-oestradiol 17-valerate per day for 6 days followed by 250 mg progesterone per day for 6 days; n=4); and oestradiol plus long duration progesterone (5 mg beta-oestradiol 17-valerate per day for 6 days followed by 250 mg progesterone per day for 12 days; n=4). Jugular venous blood samples were obtained for oestrogen and progesterone radioimmunoassays. Endometrial biopsies were obtained and total RNA was extracted. Expression of mRNA for oxytocin and glyceraldehyde 3'-phosphate dehydrogenase was assessed by RT-PCR and Southern blotting. Oxytocin mRNA abundance was significantly higher (P < 0.05) in the oestrogen-treated group than in all other groups. These data demonstrate that oestradiol priming for 6 days upregulated expression of the endometrial oxytocin gene. Progesterone treatment for either 6 or 12 days after oestradiol priming returned oxytocin mRNA abundance to levels similar to those of controls.

Eletriptan (Relpax) is a novel 5-hydroxytryptamine (serotonin)(1D/1B) agonist currently in development for the acute treatment of migraine. The aim of this work was to evaluate the relative induction potency of eletriptan in vitro compared with well characterized cytochrome P-450 (CYP) inducers with primary cultures of human hepatocytes and to relate this to the situation in vivo. Eletriptan was a weak inducer of CYP3A4 protein and cyclosporin A oxidation in four of the six cultures used, whereas rifampicin was a potent inducer in all cultures. Induction was concentration dependent and not detectable at eletriptan concentrations of 5 microM and lower. The amplitude of the increase in CYP3A4 protein and activity by 25 microM eletriptan was significantly lower, with a mean of 19 (P =.0015) and 26% (P =.0002), respectively, of that observed in response to 25 microM rifampicin. CYP2A6, a protein with minor pharmacological implication, also was induced by eletriptan and rifampicin in two cultures but was not detected in the others. The levels of other CYP proteins, including CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP2E1, were not affected by eletriptan. Because the maximum blood concentration of eletriptan in humans after a therapeutic dose (maximum 80 mg) is 0.5 microM, the in vitro model would predict no clinically significant induction of CYP3A4 protein in vivo. This has been confirmed subsequently in a clinical study, with 6beta-hydroxycortisol/cortisol ratios as marker of CYP3A4 activity. Eletriptan is therefore not an inducer of CYP3A4 at clinical doses.

In a double-blind, placebo-controlled, randomized study, 10 healthy men received either a single dose of 480 microg granulocyte colony-stimulating factor (G-CSF) or saline. Blood taken from the volunteers was stimulated with 10 microg/mL endotoxin and released cytokines were measured by enzyme-linked immunosorbent assay. Expression of G-CSF receptors on leukocytes was examined by flow cytometry and reverse transcriptase-polymerase chain reaction. Functional activity of these receptors was tested by challenging isolated leukocyte populations to release cytokines with endotoxin in the presence of G-CSF. The G-CSF treatment attenuated the release of the proinflammatory cytokines tumor necrosis factor (TNF)-alpha, interleukin (IL)-12, IL-1beta, and interferon (IFN)-gamma in ex vivo lipopolysaccharide (LPS)-stimulated whole blood. In blood from untreated volunteers the presence of G-CSF in vitro also attenuated the LPS-stimulated release of these cytokines. G-CSF in vitro also attenuated TNF-alpha release from elutriation-purified monocytes. In the presence of 10 ng/mL recombinant TNF-alpha, the attenuation of LPS-inducible IFN-gamma release by G-CSF was blunted in whole blood. However, G-CSF had no such effect on IFN-gamma release from isolated lymphocytes stimulated with anti-CD3 or a combination of TNF-alpha and IL-12. G-CSF receptor expression was detected in human neutrophils and monocytes but not in lymphocytes by means of RT-PCR as well as flow cytometry. These results indicate that G-CSF receptors expressed on monocytes are functional in modulating monokine release. We conclude that the attenuation of IFN-gamma release from lymphocytes is not a direct effect of G-CSF on these cells but is rather due to the inhibition of monocytic IL-12 and TNF-alpha release by G-CSF. (Blood. 2000;95:270-276)

The allergen-induced late nasal response is associated with a high local expression of interleukin (IL) -4, a TH2-type cytokine implicated in immunoglobulin (Ig) E production, tissue eosinophilia and other events considered to be relevant to allergic inflammation. Interaction of IL-4 with its receptor activates at least two distinct signalling pathways that culminate in the transcription of specific target genes. One pathway involves the activation of a transcription factor termed signal transducer and activator of transcription factor 6 (STAT6).

Leader binding protein-1 (LBP-1)/late SV40 factor (LSF) and ying yang-1 (YY1) transcription factors are involved in the regulation of HIV expression. In particular, YY1 and LBP-1 have been shown to cooperate in repressing HIV-1-long terminal repeat reporter gene expression by in vitro cotransfection experiments. However, no information is available on the levels of expression and activation of these transcription factors in PBMC of HIV-infected individuals. Therefore, we have evaluated the expression and DNA binding activity of YY1 and LBP-1 (LSF) in PBMC of HIV-infected individuals before, during, and after administration of IL-2 in association with antiretroviral therapy (ART), a regimen under consideration for broad clinical use in this disease based on its ability to stably raise the absolute number of circulating CD4+ T lymphocytes. Both YY1- and LBP-1 (LSF)-DNA binding were profoundly down-modulated during administration of IL-2/ART, and a proteolytic activity probably responsible for the reduced expression of the two cellular transcription factors was found activated in PBMC of individuals receiving the immunotherapeutic regimen. This study is the first evidence of modulation of cellular transcription factors following IL-2/ART administration and provides a potential correlate of the transient raises in plasma viremia early reported in patients receiving IL-2 in the absence of ART, thus underscoring the importance of always administering this cytokine to HIV-infected individuals together with potent antiretrovirals.