Urinary metabolomic analysis to identify potential markers for the diagnosis of tuberculosis and latent tuberculosis.

Tuberculosis (TB) is a serious infectious disease with high infection and mortality rates. 5%-10% of the latent tuberculosis infections (LTBI) are likely to develop into active TB, and there are currently no clinical biomarkers that can distinguish between LTBI, active TB and other non-tuberculosis populations. Therefore, it is necessary to develop rapid diagnostic methods for active TB and LTBI. In this study, urinary metabolome of 30 active TB samples and the same number of LTBI and non-TB control samples were identified and analyzed by UPLC-Q Exactive MS. In total, 3744 metabolite components were obtained in ESI- mode and 4086 in ESI + mode. Orthogonal partial least square discriminant analysis (OPLS-DA) and hierarchical cluster analysis (HCA) showed that there were significant differences among LTBI, active TB and non-TB. Six differential metabolites were screened in positive and negative mode, 3-hexenoic acid, glutathione (GSH), glycochenodeoxycholate-3-sulfate, N-[4'-hydroxy-(E)-cinnamoyl]-l-aspartic acid, deoxyribose 5-phosphate and histamine. The overlapping pathways differential metabolites involved were mainly related to immune regulation and urea cycle. The results showed that the urine metabolism of TB patients was disordered and many metabolic pathways changed. Multivariate statistical analysis revealed that GSH and histamine were selected as potential molecular markers, with area under curve of receiver operating characteristic curve over 0.75. Among the multiple differential metabolites, GSH and histamine changed to varying degrees in active TB, LTBI and the non-TB control group. The levels of GSH and histamine in 48 urinary samples were measured by ELISA in validation phase, and the result in our study provided the potential for non-invasive biomarkers of TB.

Urinary leukotrienes and histamine in patients with varying severity of acute dengue.

BACKGROUND: Vascular leak is a hallmark of severe dengue, and high leukotriene levels have been observed in dengue mouse models, suggesting a role in disease pathogenesis. We sought to explore their role in acute dengue, by assessing levels of urinary LTE4 and urinary histamine in patients with varying severity of acute dengue. METHODS: Urinary LTE4, histamine and creatinine were measured by a quantitative ELISA, in healthy individuals (n = 19), patients with dengue fever (DF = 72) and dengue haemorrhagic fever DHF (n = 48). The kinetics of LTE4 and histamine and diurnal variations were assessed in a subset of patients. RESULTS: Urinary LTE4 levels were significantly higher (p = 0.004) in patients who proceed to develop DHF when compared to patients with DF during early illness (≤ 4 days) and during the critical phase (p = 0.02), which continued to rise in patients who developed DHF during the course of illness. However, LTE4 is unlikely to be a good biomarker as ROCs gave an AUC value of 0.67 (95% CI 0.57 and 0.76), which was nevertheless significant (p = 0.002). Urinary LTE4 levels did not associate with the degree of viraemia, infecting virus serotype and was not different in those with primary vs secondary dengue. Urinary histamine levels were significantly high in patients with acute dengue although no difference was observed between patients with DF and DHF and again did not associate with the viraemia. Interestingly, LTE4, histamine and the viral loads showed a marked diurnal variation in both patients with DF and DHF. CONCLUSIONS: Our data suggest that LTE4 could play a role in disease pathogenesis and since there are safe and effective cysteinyl leukotriene receptor blockers, it would be important to assess their efficacy in reducing dengue disease severity.

Environmental cadmium exposure induces alterations in the urinary metabolic profile of pregnant women.

Cadmium (Cd) is a well-recognized, hazardous toxic heavy metal, and the adverse effects of high-level Cd exposure on human health have been well documented. However, little is known about the health effects of low-level environmental Cd exposure on pregnant women. The objective of this study was to assess urinary metabolic alterations in pregnant women exposed to environmental Cd, and to identify informative biomarkers. Urine samples from 246 pregnant women in the first trimester of pregnancy were collected, and urinary Cd concentrations were quantified using inductively coupled plasma mass spectrometry (ICP-MS). Urinary metabolomics was analyzed by ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS). Cd-related metabolic biomarkers were examined by comparing the samples of the first and third tertiles of Cd exposure classifications, using a partial least-squares discriminant (PLS-DA) model. Five putative biomarkers were identified, including L-cystine, L-tyrosine, dityrosine, histamine, and uric acid, all of which were related to oxidative stress and nephrotoxic effects induced by Cd exposure. The results show that low-level environmental Cd exposure could induce metabolite profile alterations in pregnant women, which might be associated with adverse health effects. Our findings provide new insights into the early molecular events following Cd exposure, and may be valuable for the health risk assessment of Cd exposure during pregnancy.

Dual-Mode Optical Sensing of Histamine at Nanomolar Concentrations in Complex Biological Fluids and Living Cells.

An easily synthesized fluorescein-based luminescent dye has been utilized for the dual-mode detection of histamine at nanomolar concentrations at pH 7.0 in water. The specific response to histamine was achieved by imidazole-catalyzed 'imine formation' reaction. The protocol was subsequently applied for the estimation of histamine in complex biological milieu such as human blood serum and urine samples. Furthermore, the dose-dependent cellular uptake of histamine and de novo synthesis (by thapsigargin treatment) was visualized in RAW 264.7, a mouse macrophage cell line. We have also developed portable paper strips for rapid, on-site detection of histamine without involving costly instruments.

Clinical and laboratory parameters of mast cell activation as basis for the formulation of diagnostic criteria.

Mast cell (MC) activation occurs in a number of different pathologic conditions. Acute activation is commonly seen in patients with allergic reactions, with consecutive massive release of vasoactive and proinflammatory mediator substances from MCs, leading to the clinical signs and symptoms of anaphylaxis. In these patients, serum tryptase concentrations usually increase subtantially above baseline levels. Chronic MC activation is more difficult to diagnose, especially when symptoms are mild or atypical, and no underlying disease is found. In these patients, serum tryptase levels usually are normal. In a smaller group of patients, tryptase levels are constantly elevated and may point to an occult form of mastocytosis. These patients have to be examined for MC monoclonality, other criteria of a primary MC disease, non-MC hematopoietic neoplasms, and reactive disorders producing chronic MC activation or MC accumulation. In most patients in whom MC activation is found, histamine-induced symptoms can be documented and usually respond to treatment with histamine receptor antagonists or MC stabilizers. If this is not the case, alternative explanations for symptoms and differential diagnoses have to be considered.

Identification of urinary modified nucleosides and ribosylated metabolites in humans via combined ESI-FTICR MS and ESI-IT MS analysis.

The physiological response of the human body to several diseases can be reflected by the metabolite pattern in biological fluids. Cancer, like other diseases accompanied by metabolic disorders, causes characteristic effects on cell turnover rate, activity of modifying enzymes, and RNA/DNA modifications. This results in an altered excretion of modified nucleosides and biochemically related compounds. In the course of our metabolic profiling project, we screened 24-h urine of patients suffering from lung, rectal, or head and neck cancer for previously unknown ribosylated metabolites. Therefore, we developed a sample preparation procedure based on boronate affinity chromatography followed by additional prepurification with preparative TLC. The isolated metabolites were analyzed by ion trap mass spectrometry (IT MS) and Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS). IT MS was applied for LC-auto MS(3) screening runs and MS(n(n=4-6)) syringe pump infusion experiments, yielding characteristic fragmentation patterns. FTICR MS measurements enabled the calculation of corresponding molecular formulae based on accurate mass determination (mass accuracy: 1-5 ppm for external and sub-ppm values for internal calibration). We were able to identify 22 metabolites deriving from cellular RNA metabolism and related metabolic pathways like histidine metabolism, purine biosynthesis, methionine/polyamine cycle, and nicotinate/nicotinamide metabolism. The compounds 1-ribosyl-3-hydroxypyridinium, 1-ribosyl-pyridinium, and 3-ribosyl-1-methyl-l-histidinium as well as a series of ribosylated histamines, conjugated to carboxylic acids at the N(omega)-position were found as novel urinary constituents. The occurrence of the modified nucleosides 2-methylthio-N(6)-(cis-hydroxyisopentenyl)-adenosine, 5-methoxycarbonylmethyl-2-thiouridine, N(6)-methyl-N(6)-threonylcarbamoyladenosine, and 2-methylthio-N(6)-threonylcarbamoyladenosine in human urine is verified for the first time.

Biochemical markers in the follow-up of medullary thyroid cancer.

Medullary thyroid cancer (MTC) shares biochemical features with other neuroendocrine tumors but the particular characteristics are largely unexplored. We investigated the biochemical neuroendocrine profile of MTC and whether specific markers could be useful in follow-up. In addition to the standard tumor marker calcitonin, plasma carcino-embryonic antigen (CEA), plasma catecholamines, (platelet) serotonin, chromogranin A, tryptase, and urinary markers of catecholamine, histamine, and serotonin metabolism were prospectively determined in 46 patients with histologically proven MTC. Patients were divided according to the stage of disease: group 1, no evidence; group 2, stable disease (SD); and group 3, progressive disease (PD). Plasma dopamine was increased in the majority of the patients with SD and PD; however it did not correlate with extent of disease. Elevated plasma platelet levels of serotonin were only present in patients with multiple endocrine neoplasia 2 with SD or PD but did not differ between those groups. Histamine metabolites were elevated in 20% of patients with SD and PD. In addition to plasma calcitonin, only CEA and chromogranin A could differentiate between stable and progressive MTC. MTCs are capable of synthesizing catecholamines, serotonin, and histamine metabolites underscoring that MTCs have metabolic characteristics in common with other neuroendocrine tumors. Thus far, clinical usefulness and relevance seems limited. The most useful markers in the follow-up of MTC are plasma calcitonin and CEA.

Interleukin-6, histamine, and methylhistamine as diagnostic markers for interstitial cystitis.

OBJECTIVES: To examine the specificity and sensitivity of the inflammatory markers histamine, methylhistamine, and interleukin-6 (IL-6) in the urine of patients with interstitial cystitis compared with that in healthy controls. METHODS: A total of 40 women with interstitial cystitis and 29 healthy controls collected 24-hour urine samples. During the 24 hours before urine collection, all participants refrained from consuming foods and medications that could contain bioactive amines. Methylhistamine and histamine were measured using radioimmunoassay kits and were normalized to urinary creatinine levels; IL-6 was measured using enzyme-linked immunosorbent assay. The data were analyzed by t tests, logistic regression analysis, and receiver operating characteristics. RESULTS: IL-6 and histamine were significantly greater in the patients with interstitial cystitis than in the controls (P = 0.0003 and P = 0.038, respectively). The methylhistamine levels were also greater in the patients with interstitial cystitis than in the controls, but the results did not reach significance (P = 0.063). Using a combination of IL-6 and methylhistamine/creatinine, cutoff points were established. Using these cutoff points, the sensitivity was 70.0%, specificity 72.4%, positive predictive value 77.8%, and negative predictive value 63.6%. CONCLUSIONS: All three markers--histamine, methylhistamine, and IL-6--were greater in the patients with interstitial cystitis than in the controls. A combination of methylhistamine and IL-6 could be used as a sensitive and specific marker for interstitial cystitis.

Modification of mediators of immune reaction after general anaesthesia.

UNLABELLED: The adverse reactions that may occur during a surgical intervention are of concern to anesthesiologists and allergists due to the civil responsibility they entail and the increased demand for healthcare in allergology units. The aim of the present study was to determine the prevalence of adverse reactions in our setting (Island of Lanzarote) and modifications to immune response mediators using three types of representative myorelaxants (succinylcholine, cisatracurium and vecuronium) in order to predict and prevent adverse reactions. MATERIAL AND METHODS: We performed a prospective, cross sectional, observational study in a population of 201 patients scheduled to undergo surgery in the Surgery Department of the Lanzarote General Hospital from October 1998. Three groups were retrospectively selected: vecuronium (73 patients), cisatracurium (80 patients), and succinylcholine (48 patients). Blood was extracted from all patients before and after the intervention and the following in vitro variables were evaluated: histaminemia, eosinophil cationic protein, tryptase, IgE to latex, CD4/CD8 fractions, total lymphocytes, total IgE, C3 and C4, and also the histaminuria. CONCLUSIONS: The mean age of the patients was 41 years with a predominance of women. Sixty percent had not previously undergone surgery. The mean operating time was 2 hours. Digestive surgery accounted for the greatest number of interventions (38.8 %) and most of the patients had no personal history of atopy (91.5 %). The greatest number of perioperative reactions was produced by cisatracurium (38.8 %), followed by succinylcholine (27.4 %) and vecuronium (20 %). The reactions observed were immediate type 1 and 2 reactions. All reactions were reversible without sequelae. Histaminuria levels were significantly decreased in the cisatracurium group. Histaminemia and eosinophil cationic protein showed no significant changes in any of the three groups. Tryptase concentrations in blood did not increase in the postoperative period in any of the three groups. On the contrary, concentrations were significantly lower than basal values. In the vecuronium and succinylcholine groups, CD4/CD8 fractions decreased in the postoperative period. Total lymphocytes decreased in all three groups. Total IgE tended to decrease in the cisatracurium and succinylcholine groups. IgE to latex was negative in the three groups. Specific IgE to succinylcholine was unmodified. C3 complement fraction was unmodified in all three groups and C4 fraction was reduced in the vecuronium group. In our setting and in our patients, the three myorelaxants produced immunosuppression of immune response mediators. The present study confirms that tests for allergy to myorelaxants are not indicated in the preoperative period.

Acute spinal epidural hematoma and systemic mastocytosis.

BACKGROUND: Systemic mastocytosis is a mast cell proliferative disorder affecting many organs that is rarely associated with internal bleeding. OBJECTIVE: To describe a case of spinal epidural hematoma in a patient with past medical history of urticaria pigmentosa and osteoporosis diagnosed with systemic mastocytosis. CASE REPORT: A 63-year-old woman with urticaria pigmentosa was admitted to hospital for severe back pain after minor trauma. Physical examination showed pain on pressing T12 and L1 spinous processes, bilateral Lasègue sign, absent ankle jerk, and extensor plantar response. Computed tomography disclosed L3 fracture, and magnetic resonance imaging revealed spinal epidural hematoma and T2 hyperintensive scattered vertebral foci that suggested malignancy. The 24-hour urine histamine was very high. Mast cell infiltration was found in bone marrow biopsy. Because power was normal and there was no clinical sphincter disorder, the patient was successfully treated with conservative care. CONCLUSIONS: To our knowledge, acute intraspinal epidural hematoma has never been associated with mastocytosis. The hematoma was likely related to the vertebral fracture as well as a hemorrhagic diathesis due to anticoagulants released by local mast cells.

Surrogate markers of disease in mastocytosis.

Measurement of surrogate mast cell-related products in blood or urine is often performed to assess disease extent in evaluating patients with mastocytosis. Serum tryptase and 24-hour urine histamine metabolites are the most commonly used surrogate markers of mastocytosis. In addition, several novel markers including soluble CD117 and soluble CD25 have been identified in recent studies. The utility and the pitfalls of each of these measurements are discussed.

Intravesical sodium hyaluronate inhibits the rat urinary mast cell mediator increase triggered by acute immobilization stress.

PURPOSE: Mast cell activation and stress have been suggested as factors in the pathogenesis of interstitial cystitis, a painful disorder of the bladder that is diagnosed more frequently in women and characterized by increased urgency and frequency with absent infection. Intravesical sodium hyaluronate has been used to treat interstitial cystitis due to its possible replenishment of bladder glycosaminoglycans. We investigated the effect of sodium hyaluronate on the activation of bladder mast cell and release of proinflammatory mediators in the urine induced by acute immobilization stress in rats. MATERIALS AND METHODS: Using anesthesia a catheter was inserted in the bladder of 170 gm. female Sprague-Dawley rats. After emptying post-void residual urine a solution of normal saline, 0.08% or 0.4% sodium hyaluronate was introduced for 30 minutes. Each rat was allowed to recover from anesthesia and stressed for 30 minutes by confining it in a clear acrylic plastic immobilizer, while urine was continuously collected. Urinary histamine, rat mast cell protease-I and interleukin (IL)-6 were then determined. At the end of the experiments each rat was sacrificed by CO2 asphyxiation, and the bladder was removed and fixed with 4% paraformaldehyde. Frozen sections were stained with acidified toluidine blue, and the mast cell number and degree of activation were determined by granule extrusion and reduced cellular staining. RESULTS: Mean bladder mast cell activation plus or minus standard deviation in 6 control rats was 30.4% +/- 3.7% but it increased to 76.2% +/- 6.1% in 6 stressed animals (p = 0.0001). Intravesical administration of 0.4% sodium hyaluronate for 30 minutes in 6 rats before stress reduced mean bladder mast cell activation by 69.7% to 23.1% +/- 6.1% compared with stressed controls (p = 0.0003). However, compared to itself before stress there was no significant difference, indicating complete inhibition in 6 rats. Intravesical 0.08% sodium hyaluronate had a weaker inhibitory effect in 6 rats, decreasing mean degranulation by 22.5% to 59.1% +/- 7.6% (p = 0.02). In 6 rats stress increased the total mean amount of urinary rat mast cell protease-I by 271% from 0.14 +/- 0.09 to 0.52 +/- 0.17 ng. (p = 0.008). Pretreatment with 0.4% sodium hyaluronate reduced mean rat mast cell protease-I 80.8% compared with stressed controls (p = 0.008) and prevented any increase in response to stress in the same group of 8 rats with a mean pre-stress and post-stress level of 0.09 +/- 0.04 and 0.1 +/- 0.04 ng., respectively (p = 0.8). Acute stress increased mean urinary histamine in 6 rats 40.2% from 137.3 +/- 29.7 before to 193.7 +/- 7.6 ng./ml. after stress (p = 0.004). Pretreatment with 0.4% sodium hyaluronate reduced mean histamine 7.1% compared with stressed controls but completely prevented any increase in the same group of 8 rats, in which it was 174.5 +/- 23.1 before and remained 179.4 +/- 9.9 ng./ml. after stress (p = 0.75). Acute stress in 7 rats also increased the mean amount of IL-6 released in the urine by 31.5% from 775.9 +/- 69.2 to 1,021.1 +/- 93.3 pg./ml. (p = 0.007). Pretreatment with 0.4% sodium hyaluronate in 9 rats reduced mean IL-6 17% compared with stressed controls but again prevented any increase from baseline, since the value was 898.6 +/- 299.3 before and 824.4 +/- 196.4 pg./ml. after stress (p = 0.03). CONCLUSIONS: Immobilization stress induces bladder mast cell activation and the secretion of proinflammatory mediators, which are inhibited by sodium hyaluronate. Intravesical sodium hyaluronate may be a useful therapeutic option for interstitial cystitis, especially in patients with bladder mastocytosis who have symptom exacerbation with stress.

Immunologic studies in presumed amniotic fluid embolism.

OBJECTIVE: To evaluate the potential role of immunologic mechanisms that involve mast cell degranulation (anaphylaxis) or complement activation in the mechanism of amniotic fluid embolism. METHODS: This study was a case series of nine women with presumed amniotic fluid embolism and a control group of 22 women who had normal labor. Women were from community and tertiary referral hospitals in Japan and the United States. Main outcome measures were maternal peripartum complement levels (C3 and C4), serum levels of tryptase, urinary histamine concentrations, and serum levels of a fetal antigen (sialyl Tn). RESULTS: Serum tryptase and urinary histamine measurements were negative in women with amniotic fluid embolism; seven of nine had elevated levels of fetal antigen. All eight who had serum available for testing had abnormally low levels of complement. Mean C3 level of 44.0 mg/dL and C4 level of 10.7 mg/dL were significantly lower than corresponding postpartum control values of 117.3 mg/dL and 29.4 mg/dL (P =.018 for C3, P =.012 for C4). Postpartum C3 and C4 levels decreased by 8% and 5%, respectively, compared with intrapartum values (P =.003 for C3, P =.021 for C4) but were still within normal range. CONCLUSION: Serologic findings suggest a role for complement activation in the mechanism of amniotic fluid embolism. Laboratory data from this series did not implicate mast cell degranulation (anaphylaxis) in the pathophysiology of the disease.

CNS induced neurogenic cystitis is associated with bladder mast cell degranulation in the rat.

PURPOSE: To determine if bladder mast cell degranulation is involved in the genesis of neurogenic cystitis induced by pseudorabies virus (PRV) invasion of the central nervous system (CNS). MATERIALS AND METHODS: Rats received a total of 4 x 106 plaque forming units (pfu) of PRV-Bartha in the abductor caudalis dorsalis (ACD) muscle. Granulated bladder mast cells per mm2 of bladder tissue and urine histamine content were monitored as the cystitis developed over the next few days. In a subgroup of rats, intravesical resiniferatoxin was used to remove capsaicin-sensitive sensory bladder afferents, while another subgroup was pretreated with a mast cell degranulator. RESULTS: PRV injection into the ACD muscle leads to neurogenic cystitis. Histamine levels were elevated in the urine of virus injected rats before any behavioral or microscopical signs of cystitis were present. When the cystitis became clinically manifest, urine histamine returned to control levels, and the number of granulated mast cells dropped significantly. Rats in which capsaicin-sensitive afferents had been removed did not show any signs of cystitis, or increase in urine histamine, or change in the number of granulated mast cells. Pretreatment of animals with a mast cell degranulator completely prevented the appearance of cystitis without altering the CNS disease. CONCLUSION: These results provide further evidence that mast cells are involved in neurogenic cystitis induced by changes in CNS activity.

Markers of mast cell degranulation.

Mast cells are the primary effector cells of immediate hypersensitivity reactions in humans. Upon mast cell activation both preformed and newly synthesized mediators are secreted. Histamine can be measured by fluorometric assays, radioenzymatic assays, and immunoassays. These methods have been applied to plasma and urine to detect histamine that had been released in vivo and to release histamine in vitro from basophils and mast cells. Another mast cell constituent is tryptase, which is a more selective marker of mast cells, because negligible amounts are found in basophils. beta-Tryptase is stored in secretory granules and is actively released when mast cells degranulate. alpha-Protryptase remains in the proenzyme form and is constitutively released from mast cells, and consequently its level in serum reflects total numbers of mast cells. alpha-Protryptase levels are elevated in serum at baseline in subjects with systemic mastocytosis, whereas beta-tryptase is elevated in serum from subjects with systemic anaphylaxis. These markers serve as precise clinical indicators of the involvement of mast cells in human disease.

Effects of local and systemic budesonide on allergen-induced airway reactions in the pig.

1. In this study, an attempt was made to distinguish between local and systemic effects of low doses of the topical glucocorticoid, budesonide. The effect of aerosolized budesonide administered to the lower airways versus intravenously administered budesonide on the acute and late response to nebulized Ascaris suum extract in the lung, was evaluated in the minipig after active sensitization with purified A. suum antigen. Budesonide was administered once, 1 h prior to A. suum challenge and airway reactions and mediator release were observed for 8 h after allergen challenge. 2. In the budesonide aerosol group (n = 6), 10.2 +/- 1.2 micrograms kg-1 budesonide was given locally and in the budesonide infusion group (n = 5), 5 micrograms kg-1 was given intravenously. The area under the plasma concentration curve for budesonide during the experiment was 11.4 +/- 1.2 and 10.3 +/- 1.2 nM h in the budesonide aerosol and budesonide infusion group, respectively (no significant difference). The lung tissue content of budesonide in the two groups was 45.2 +/- 4.9 and 18.4 +/- 3.5 nmol kg-1 dry tissue, respectively, 8 h after allergen challenge (P < 0.05). For comparison, 6 pigs were given budesonide vehicle as an infusion prior to A. suum challenge. 3. Total lung resistance (RL) increased acutely (maximal response within 15 min) in the budesonide aerosol, budesonide infusion and budesonide vehicle groups (by 91 +/- 40, 150 +/- 86 and 80 +/- 27%, respectively). The acute reaction partially resolved at about 1 h and was followed by a late increase in RL in the budesonide infusion and budesonide vehicle groups (by 251 +/- 148 and 281 +/- 136% at 8 h, respectively). However, no late change in RL was seen in the budesonide aerosol group (7 +/- 24%). 4. Aerosolized budesonide had a protective effect in that it attenuated the late changes in arterial blood gas and pH as well as the late elevation of plasma catecholamines. Budesonide given as an infusion did not protect against the late changes in these parameters. However, budesonide aerosol or infusion did not inhibit the late vasodilation in the bronchial circulation. 5. Histamine and cysteinyl-leukotrienes were released during the acute reaction as measured by urinary concentration of methylhistamine and leukotriene E4 respectively. There was no release of histamine during the late reaction. A late increase in leukotriene E4 was observed in 2 of the budesonide infusion and 3 of the budesonide vehicle pigs, whereas no such increase was seen in any of the budesonide aerosol pigs. 6. Budesonide concentration in lung tissue, but not in plasma at 8 h correlated negatively with the late increase in RL (P < 0.05, r = -0.53, n = 10), whereas budesonide concentration in plasma but not in lung tissue correlated negatively with the late decrease in dynamic compliance (P < 0.05, r = -0.67, n = 12). 7. This study has shown that a single low dose of locally administered budesonide can inhibit the late allergic reaction in the pig lower airways. If budesonide was given as an intravenous infusion in a dose yielding a plasma concentration similar to that seen after the aerosol treatment, the protective effect of budesonide was poor. It may be suggested that the tissue-bound portion of budesonide affects local mechanisms involved in the development of late changes in the airways (RL), although it does not affect the late increase in bronchial blood flow. We conclude that the inhibitory effect of budesonide on the allergen-induced late reaction in the pig airways relates to tissue-bound steroid, and that the systemic component is of less importance.

Mast cell and substance P-positive nerve involvement in a patient with both irritable bowel syndrome and interstitial cystitis.

Many patients with interstitial cystitis (IC) also have irritable bowel syndrome (IBS), both of which occur overwhelmingly in women, are characterized by pain, and worsen under stress. Bladder and colon biopsies of a female patient with both IC and IBS were evaluated immunohistochemically. There were 40 +/- 10 mast cells (MC)/mm2 (normal, less than 10) in the bladder, which were degranulated. The colon contained 148 +/- 11 MC/mm2 (normal, less than 50), mostly close to numerous substance P (SP)-positive nerves. Histamine, methylhistamine, and the unique MC enzyme tryptase were evaluated in 24-hour urine during two flare-ups. These results may help explain the concurrent presentation and the painful nature of these syndromes.

Diurnal variation of urinary leukotriene E4 and histamine excretion rates in normal subjects and patients with mild-to-moderate asthma.

BACKGROUND: Leukotriene E4 (LTE4) and histamine excreted into the urine reflect the in vivo synthesis and release of cysteinyl leukotrienes and histamine, respectively. We examined the diurnal variation of the excretion rate of these mediators over 4 consecutive days in normal subjects (n = 5) and patients with stable mild-to-moderate asthma (n = 8). METHODS: Sixteen consecutive 6-hour urine samples were collected over 4 days. Urinary LTE4 concentrations were determined by reverse-phase high-pressure liquid chromatography, followed by ELISA. Urinary histamine concentrations were measured by ELISA. The excretion rates of these compounds were normalized relative to urinary creatinine content. RESULTS: The mean urinary LTE4 excretion rate was 83.8 +/- 38.2 pg/mg creatinine (mean +/- SD) in normal subjects; in patients with asthma, the urinary LTE4 excretion rate (110.0 +/- 59.2 pg/mg creatinine) was significantly higher than that in normal subjects (p < 0.05). The urinary histamine excretion rate was not different between normal subjects (24.0 +/- 12.5 ng/mg creatinine) and patients with asthma (31.5 +/- 25.8 ng/mg creatinine). A robust and systematic within-day variation (p < 0.01), but no day-to-day variation, was observed in histamine excretion rate. Although the magnitude of variation in LTE4 excretion within a day was significantly greater in patients with asthma than in normal subjects (p < 0.05), we could not identify any specific diurnal variation pattern in either the normal or the asthma group. No significant correlation was observed between urinary LTE4 and histamine excretion rate within any subject. CONCLUSIONS: Patients with asthma excrete LTE4 in the urine at a greater rate than normal subjects. Although no systematic variation in urinary LTE4 excretion rates over the course of a day was observed in either normal subjects or patients with stable asthma, the presence of a systematic diurnal variation of urinary histamine excretion exists in both groups.

Mobilization of gastric histamine during repeated administration of a proton potassium adenosine triphosphatase inhibitor in intact and antrectomized rats.

Intact and antrectomized female rats were treated with the potent proton pump inhibitor, E3810 (daily 40 mg/kg weight, s.c.) for 4 weeks. Plasma gastrin concentration and urinary excretion of N-terminal big gastrin increased until day 14 and persisted at a high level in intact rats treated with E3810, but did not increase in antrectomized rats. Urinary excretion of histamine increased progressively and reached 7 times the control value following 4 weeks of treatment with E3810 in intact rats, but not in antrectomized rats. At the termination of the treatment, the endocrine cell density in the oxyntic mucosa of intact rats had increased by 85% with increased histamine content and elevated histidine decarboxylase activity, while antrectomized rats showed a low histamine level and low histidine decarboxylase activity. Administration of gastrin-17 I (10 micrograms/kg weight, sc) itself caused a significant increase in urinary excretion of histamine, which was inhibited by the specific gastrin receptor antagonist, L-365,260. These results suggests that the massive urinary excretion of histamine caused by the treatment with E3810 reflects gastrin-induced mobilization of gastric histamine and that neither E3810 itself nor E3810-induced luminal pH elevation has direct effects on mobilization of oxyntic mucosal histamine.