Use of Vitex agnus-castus in patients with menstrual cycle disorders: a single-center retrospective longitudinal cohort study

PURPOSE

To evaluate clinical characteristics, quality of life (QoL) and effectiveness in patients with menstrual cycle disorders (MCDs) including abnormal uterine bleeding, dysmenorrhea and mastodynia/mastalgia related to premenstrual syndrome taking the Vitex agnus-castus (VAC) products Cyclodynon® or Mastodynon® in a real-world setting.

METHODS

A single-center retrospective longitudinal cohort study (3 ± 1 months), using data obtained from healthcare data archive and telephone interviews. The main study variables were changes in bleeding, menstrual pain, breast tenderness and patients' QoL.

RESULTS

Data from 1700 women with a mean age of 30.2 years (± 6.3) were analyzed. The most common MCDs were dysmenorrhea (43.8%) and mastodynia/mastalgia (21.1%). Three-month treatment with VAC extract substantially decreased the percentage of patients with irregular cycle (from 9.1% to 0.1%) and breast tenderness (from 39.9% to 0.8%). Improvement in bleeding intensity, frequency and menstrual pain was experienced by 83.4%, 79.2%, and 85.2% of the patients, respectively. When analyzed by disease category, these parameters improved in almost all dysmenorrhea patients, while they improved to a lesser extent in mastodynia/mastalgia patients. QoL improved in all aspects, but was reported by a higher proportion of dysmenorrhea patients compared to mastodynia/mastalgia patients. Treatment was overall well tolerated with a favorable safety profile.

CONCLUSION

These real-world data demonstrate the effectiveness of the VAC-containing products Cyclodynon® and Mastodynon® in the three-month treatment of MCDs, with a pronounced improvement in key disease symptoms and QoL. Intriguingly, while QoL was generally greatly improved, the response to VAC therapy varied depending on the type of underlying MCD.

Phytotherapy (BNO 1045) of Acute Lower Uncomplicated Urinary Tract Infection in Women Normalizes Local Host Responses

INTRODUCTION

Acute lower uncomplicated urinary tract infection (uUTI) affects a large proportion of women. Increased antimicrobial resistance has created an urgent need for novel therapeutics and the phytotherapeutic drug BNO 1045 (Canephron® N) has previously been shown to be noninferior to standard antimicrobial stewardship. This sub-analysis from a randomized, double-blind, controlled phase III noninferiority clinical trial using BNO 1045 versus fosfomycin to treat uUTI aimed to determine how urine cytokine levels are altered by the two different treatments.

METHODS

Urine samples from a predefined subset of women diagnosed with uUTI (18-70 years) and treated with BNO 1045 (n = 58) or fosfomycin (n = 69) were analyzed for urine levels of IL-6 and IL-8, using analyte-to-creatinine ratios.

RESULTS

BNO 1045 treatment showed similar effects to fosfomycin treatment in reducing both urine IL-6 and IL-8 levels. Mean IL-6 and IL-8 levels were markedly reduced in all patients regardless of treatment. BNO 1045 treatment decreased urine IL-8 significantly (p = 0.0142) and showed a trend toward reduction of urine IL-6 (p = 0.0551). Fosfomycin treatment reduced both IL-6 and IL-8 levels significantly (p = 0.0038, <0.0001 respectively).

CONCLUSION

BNO 1045 is, in addition to reducing symptoms, comparable to fosfomycin treatment in reducing the local inflammatory response associated with uUTI.

Contribution of Symptomatic, Herbal Treatment Options to Antibiotic Stewardship and Microbiotic Health

Epithelial surfaces in humans are home to symbiotic microbes (i.e., microbiota) that influence the defensive function against pathogens, depending on the health of the microbiota. Healthy microbiota contribute to the well-being of their host, in general (e.g., via the gut-brain axis), and their respective anatomical site, in particular (e.g., oral, urogenital, skin, or respiratory microbiota). Despite efforts towards a more responsible use of antibiotics, they are often prescribed for uncomplicated, self-limiting infections and can have a substantial negative impact on the gut microbiota. Treatment alternatives, such as non-steroidal anti-inflammatory drugs, may also influence the microbiota; thus, they can have lasting adverse effects. Herbal drugs offer a generally safe treatment option for uncomplicated infections of the urinary or respiratory tract. Additionally, their microbiota preserving properties allow for a more appropriate therapy of uncomplicated infections, without contributing to an increase in antibiotic resistance or disturbing the gut microbiota. Here, herbal treatments may be a more appropriate therapy, with a generally favorable safety profile.

Non-Antibiotic Herbal Therapy (BNO 1045) versus Antibiotic Therapy (Fosfomycin Trometamol) for the Treatment of Acute Lower Uncomplicated Urinary Tract Infections in Women: A Double-Blind, Parallel-Group, Randomized, Multicentre, Non-Inferiority Phase III Trial

INTRODUCTION

This randomized, controlled, Phase III non-inferiority clinical trial aimed to determine whether herbal therapy with Canephron® N (BNO 1045) is non-inferior to fosfomycin trometamol (FT) in treating acute lower uncomplicated urinary tract infections (uUTIs).

MATERIALS AND METHODS

Women aged 18-70 years with typical symptoms of newly diagnosed acute lower uUTIs were randomized to BNO 1045 (n = 325) or FT (n = 334), with corresponding matched placebo. The primary endpoint was the proportion of patients who received additional antibiotics (ABs) to treat uUTIs between Days 1 and 38 ±3.

RESULTS

Between Days 1 and 38, 238 (83.5%) patients in the BNO 1045 group and 272 (89.8%) patients in the FT group received no additional ABs. At a 15% non-inferiority margin, BNO 1045 was non-inferior to FT in treating uUTIs (non-AB rate difference: -6.26%; 95% CI -11.99 to -0.53%; 2-sided p = 0.0014). Adverse event rates were similar between groups, with higher rates of gastrointestinal disorders in the FT group and pyelonephritis in the BNO 1045 group. During the trial, no patient died or discontinued due to a treatment-related adverse event.

CONCLUSIONS

BNO 1045 has the potential to reduce outpatient use of ABs for uUTIs and thus may have a significant impact on antimicrobial stewardship strategies.

TRIAL REGISTRATION

NCT02639520, EudraCT number 2013-004529-99.

Clinical Application of Fiber Visualization with LIC Maps Using Multidirectional Anisotropic Glyph Samples (A-Glyph LIC)

Recently, a fiber visualization method for high-angular resolution diffusion-weighted magnetic resonance imaging (MRI) data was proposed using a multiple-kernel line integral convolution (LIC) algorithm and an anisotropic spot pattern. This processing routine leads to high contrast color-coded LIC maps that are capable of visualizing local anisotropy information and regional fiber architecture. In this paper, we evaluate and validate this method by applying it to simulated datasets and to in vivo diffusion MRI data of children and adults with different disease conditions and healthy volunteers. Compared to routine clinical fiber visualization (color-coded fractional anisotropy, FA maps, and fiber tractography), it has the advantage of visualizing complex local fiber architecture in a fully automated way. The results indicate that this method is capable of reliably delineating normal fiber architecture and fibers infiltrated, displaced, or disrupted by lesions and is therefore a promising tool in the clinical context.

Strain-specific differences in pili formation and the interaction of Corynebacterium diphtheriae with host cells

BACKGROUND

Corynebacterium diphtheriae, the causative agent of diphtheria, is well-investigated in respect to toxin production, while little is known about C. diphtheriae factors crucial for colonization of the host. In this study, we investigated strain-specific differences in adhesion, invasion and intracellular survival and analyzed formation of pili in different isolates.

RESULTS

Adhesion of different C. diphtheriae strains to epithelial cells and invasion of these cells are not strictly coupled processes. Using ultrastructure analyses by atomic force microscopy, significant differences in macromolecular surface structures were found between the investigated C. diphtheriae strains in respect to number and length of pili. Interestingly, adhesion and pili formation are not coupled processes and also no correlation between invasion and pili formation was found. Using RNA hybridization and Western blotting experiments, strain-specific pili expression patterns were observed. None of the studied C. diphtheriae strains had a dramatic detrimental effect on host cell viability as indicated by measurements of transepithelial resistance of Detroit 562 cell monolayers and fluorescence microscopy, leading to the assumption that C. diphtheriae strains might use epithelial cells as an environmental niche supplying protection against antibodies and macrophages.

CONCLUSIONS

The results obtained suggest that it is necessary to investigate various isolates on a molecular level to understand and to predict the colonization process of different C. diphtheriae strains.

Is the head position during preoperative image data acquisition essential for the accuracy of navigated brain tumor surgery?

OBJECTIVE

To analyze the influence of head positioning during preoperative image data acquisition on intraoperative accuracy of modern neuronavigation systems.

MATERIAL AND METHODS

All measurements were performed preoperatively before opening the head. In 24 patients, preoperative MR image data acquisition was performed twice on a 0.5 T scanner using a contrast-enhanced T1-weighted sequence; first in the neutral head position, and thereafter in the surgical head position for pterional craniotomy. For both data sets, the Sylvian fissure, the central sulcus, and the superior and inferior temporal sulci were depicted on the patient's scalp using the frameless neuronavigation system EasyGuide Neurotrade mark. At the beginning of surgery, with the head fixed in a Mayfield clamp and an articulated instrument holder being used for fixation of the navigation system's pointer, the distances of 10 correlating points of the sulci for the two data sets were measured. To evaluate the accuracy of the navigation system in this experimental set-up, a phantom study was also performed.

RESULTS

The phantom study revealed a mean inaccuracy of 1.6 mm (range 0.1-2.3 mm, standard deviation 0.6 mm). The patient study revealed a mean inaccuracy of 1.8 mm (range 0.4-2.8 mm, standard deviation 0.5 mm).

CONCLUSIONS

The data suggest that the positioning of the patient's head during preoperative imaging plays no relevant role in intraoperative accuracy of neuronavigation. However, further studies and a larger number of patients with various pathologies in different regions of the brain are necessary to obtain a better understanding of the problem of brain shift in neuronavigation due to patient positioning alone, and to avoid procedure-related operative morbidity.

In vivo 3D visualization of normal pyramidal tracts in human subjects using diffusion weighted magnetic resonance imaging and a neuronavigation system

We describe the potential of anisotropic diffusion weighted imaging to visualize the course of large cerebral fiber tracts. Five healthy volunteers were investigated at a field strength of 1.5 Tesla, employing a spin-echo diffusion weighted sequence with gradient sensitivity in six non-collinear directions to visualize the course of the pyramidal tracts. The pyramidal tracts were segmented and reconstructed for three-dimensional visualization. Reconstruction results together with a fusioned high resolution 3D T1 weighted image data set were available in a customized neuronavigation system. Origination in the primary motor cortex, convergence in the centrum semiovale, the posterior limb of the internal capsule, the cerebral peduncles, the splitting at the level of the pons, and the pyramidal decussation were identified in all subjects. Fiber tract maps might have the prospect of guiding neurosurgical interventions, especially when being linked to a neuronavigation system. Other potential applications include the demonstration of the anatomical substrate of functional connectivity in the human brain.

Lactate and postischemic recovery of energy metabolism and electrical activity in the isolated perfused rat brain

The aim of the present study was to evaluate whether lactate can maintain the energy metabolism and electrical activity of isolated perfused rat brain in the absence of glucose. To exhaust cerebral glucose stores and simultaneously raise endogenous lactate, complete ischemia was induced. After ischemia, when a glucose-free perfusate was supplied, restoration of interstitial potassium (Ke+), cortical discontinuous current (DC) potential, electroencephalogram (EEG) activity, and ATP and phosphocreatine (PCr) was not significantly different from postischemic recovery findings when a glucose-containing perfusate was used. In the group receiving glucose-free perfusate, postischemic application of 1 mM iodoacetic acid did not inhibit the recovery of electrical activity, Ke+, or DC potential. After recovery of Ke+ in glucose-free reperfusion, a 20-30-Hz EEG pattern appeared and was maintained for about 20 min followed by disappearance of spontaneous electrical activity. An abrupt increase of Ke+, a steep negative DC shift, and a substantial decrease of ATP and PCr occurred after about 22 min of reperfusion. During the first 5 min of glucose-free reperfusion, consumption of lactate was significantly higher (0.89 mumol/g wet weight/min) than during reperfusion with medium containing glucose (0.41 mumol/g ww/min). Increasing amounts of tissue lactate prolonged maintenance of electrical function in glucose-free reperfusion. This correlation could not be found for free fatty acids. In conclusion, after a few minutes of ischemia, the brain is able to recover cellular ion transport and electrical activity without a supply of glucose, preferentially by combustion of lactate accumulated in brain tissue. This mechanism is only useful during a limited time period until the lactate accumulated during ischemia is combusted.

Production of thromboxane and prostaglandins in human blood in the presence of thromboxane synthase inhibitors: a comparison of RIA and GC/MS determinations

The radioimmunological determination (RIA) of primary prostaglandins (PGs) in serum and plasma was evaluated with gas chromatography/mass spectrometry (GC/MS). Human blood was stimulated in vitro in the presence or absence of the specific thromboxane synthase inhibitor ridogrel. TxB2, 6-keto-PGF1 alpha, PGE2, PGD2 and PGF2 alpha were determined with RIA and GC/MS on the same samples. For GC/MS analysis, prostanoids were extracted and derivatized to their methoximepentafluorobenzyl-esters-trimethylsilyl-ethers. An excellent correlation was observed between levels of all eicosanoids determined by RIA or GC/MS (r = 0.996-0.999) when plasma was spiked with known amounts of PGs and TxB2 (2-500 ng/ml). In stimulated blood, with or without inhibition of thromboxane synthase, the correlation between RIA and GC/MS values remained good, except for 6-keto-PGF1 alpha. RIA largely overestimated the levels of 6-keto-PGF1 alpha and no significant correlation was found with levels detected by GC/MS. The results demonstrate the importance of corroborating the reliability of RIA with GC/MS.

Determination of 6-keto-PGF1 alpha, 2,3-dinor-6-keto-PGF1 alpha, thromboxane B2, 2,3-dinor-thromboxane B2, PGE2, PGD2 and PGF2 alpha in human urine by gas chromatography-negative ion chemical ionization mass spectrometry

A method for quantification of 6-keto-PGF1 alpha, 2,3-dinor-6-keto-PGF1 alpha TXB2, 2,3-dinor TXB2, PGE2, PGD2 and PGF2 alpha in human urine samples, using gas chromatography-negative ion chemical ionization mass spectrometry, is described. Deuterated analogues were used as internal standards. Methoximation was carried out in urine samples which were subsequently applied to phenylboronic acid cartridges, reversed-phase cartridges and thin-layer chromatography. The eluents were further derivatized to pentafluorobenzyl ester trimethylsilyl ethers for final quantification by gas chromatography-mass spectrometry. The overall recovery was 77% for tritiated 6-keto-PGF1 alpha and 55% for tritiated TXB2. Urinary levels of prostanoids were determined in a group of six volunteers before and after intake of the thromboxane synthase inhibitor Ridogrel, and related to creatinine clearance.

A rapid redistribution of hydrogen ions is associated with depolarization and repolarization subsequent to cerebral ischemia reperfusion

1. The aim of this study was to examine the rapid changes in extracellular hydrogen ion activity [( H+]o or pHo) which are associated with depolarization and repolarization subsequent to cerebral ischemia reperfusion. Two parallel studies were performed with different rat models of ischemia: repetitive severe ischemia produced in anesthetized animals by occlusion of the vertebral and carotid arteries and temporary interruption of blood flow in isolated brain. [H+]o and direct current potential (DC potential) were recorded simultaneously in all experiments. Examination of these two parameters was supplemented by recording tissue concentration of carbon dioxide (PtCO2) in the four-vessel occlusion model and assaying major metabolites involved in energy production in experiments with isolated brains. 2. Measurements of [H+]o during ischemia consistently revealed a steady increase of [H+]o on which was superimposed an abrupt and transient fall in [H+]o closely related to the occurrence of the fast negative shift of DC potential characterizing brain-cell depolarization. Analysis of the relationship between the magnitude of the transient fall in H+ and the level of [H+]o at which this occurred showed that the amplitude of the transient fall in H+ increased with tissue acidosis. 3. We propose that this phenomenon is indirect evidence that rapid transfer of acid equivalents occurs across the plasmalemma, concomitantly to its depolarization. Both events probably result from a common cause, i.e., nonspecific increase of the cell-membrane permeability to ions subsequent to opening of membrane channels. 4. Early on during recirculation, an acidotic [H+]o shift associated with membrane repolarization was clearly visible whenever the ionic gradients recovered rapidly.(ABSTRACT TRUNCATED AT 250 WORDS)

Sequence analysis of the promoter region of the glioblastoma derived T cell suppressor factor/transforming growth factor (TGF)-beta 2 gene reveals striking differences to the TGF-beta 1 and -beta 3 genes

Human glioblastoma cells secrete a factor termed glioblastoma derived T cell suppressor factor (G-TsF) or transforming growth factor beta 2 (TGF-beta 2) which inhibits the response of T cells to mitogenic or antigenic stimulation. In the present study we isolated the promoter region of the G-TsF/TGF-beta 2 gene. The promoter region shares no homology to the promoter of the TGF-beta 1 or the 5' region of the TGF-beta 3 gene and harbours several familiar DNA motifs, including the cytokine-1 region, an octamer-like sequence, Sp1- and AP-2-like elements and a putative NF-kappa B site. In contrast to the TGF-beta 1 gene, the G-TsF/TGF-beta 2 gene contains three TATA-like sequences but lacks an AP-1 site. To understand the cell type specificity of expression of G-TsF/TGF-beta 2, the individual contribution of the DNA elements detected in the promoter has to be analysed in further studies.

Eicosanoids in rat brain during ischemia and reperfusion--correlation to DC depolarization

The effects of complete ischemia on cerebral arachidonic acid (AA) metabolism were investigated in the isolated perfused rat brain. During 12.5 min of ischemia, AA, 5-hydroxy-6,8,11,14-eicosatetraenoic acid, and 15-hydroxy-5,8,11,13-eicosatetraenoic acid increased 129-, 4-, and 10-fold, respectively, while subsequent reperfusion for 30 min resulted in normalized levels independently of the duration of preceding ischemia. Prostaglandin (PG) F2 alpha, PGE2, PGD2, 6-keto-PGF1 alpha, and thromboxane (Tx) B2 remained at preischemic levels during 12.5 min of complete ischemia. However, at the end of subsequent reperfusion for 30 min, the levels of the prostanoids PGF2 alpha, PGE2, PGD2, 6-keto-PGF1 alpha, and TxB2 increased according to the preceding ischemic time. The levels reached a maximum after 7.5 min of ischemia and were elevated by 7-, 14-, 48-, 3-, and 30-fold, respectively. A prolongation of ischemia of up to 12.5 min was not associated with further increases of prostanoids at the end of reperfusion. The mechanisms underlying the metabolism of eicosanoids are discussed in relation to the changes of cortical direct current potential.

Sp1 transcription factor binds DNA and activates transcription even when the binding site is CpG methylated

In vertebrates, a negative correlation between gene activity and CpG methylation of DNA, notably in the promoter region, is well established. Therefore, it is conceivable that differential binding of transcription factors to methylated versus unmethylated binding sites is crucial for gene activity. Since the consensus binding site of transcription factor Sp1 contains a central CpG, we have investigated the binding of Sp1 factor to unmethylated and synthetically CpG-methylated DNA. A strong Sp1 binding site was methylated on both strands at two CpG positions, located in the center and at the periphery of the recognition sequence. Our studies show that neither binding in vitro, nor transcription in vivo and in vitro are affected by methylation of the Sp1 binding site. We discuss the possibility that binding of Sp1 factor, which is often associated with promoters of housekeeping genes, prevents CpG methylation.

The interactions of propranolol and ketanserin

Ten healthy volunteers received a single 10 mg intravenous dose of the 5-hydroxytryptamine-2 serotonin antagonist ketanserin in the control state and again during coadministration of propranolol, 80 mg b.i.d. There were no differences between control and propranolol treatment conditions in ketanserin volume of distribution (5.2 vs. 3.8 L/kg), elimination half-life (6.6 vs. 4.7 hours), clearance (9.7 vs. 10.0 ml/min/kg), or 72-hour excretion of intact ketanserin (0.7% vs. 0.7% of dose) or ketanserinol (21.8% vs. 24.9% of dose). In a second study, eight volunteers received a 160 mg oral dose of propranolol hydrochloride in the control state and again during treatment with ketanserin, 40 mg b.i.d. There were no significant differences between control and ketanserin conditions in the time of peak serum propranolol concentration (2.1 vs. 1.5 hours after dosage) or elimination half-life (3.8 vs. 4.1 hours). However, ketanserin increased peak serum propranolol concentrations (169 vs. 233 ng/ml) and reduced oral clearance (39 vs. 27 ml/min/kg); the differences were not statistically significant (0.05 less than P less than 0.1) with a sample size of eight. Thus therapeutic doses of propranolol in healthy volunteers do not alter the kinetics of a single dose of ketanserin. Therapeutic doses of ketanserin may impair oral clearance of propranolol, leading to increased area under the serum concentration curve and higher peak serum levels.

Studies on the intracerebral metabolism of anticonvulsant drugs--II. Disposition of carbamazepine in the isolated perfused rat brain

Carbamazepine (CBZ) was perfused (85 nmoles/ml) through the isolated brains of rats. After 2 hr the mean regional concentrations of the drug were between 170 and 234 nmoles/g wet weight. The total brain content of CBZ was 390 nmoles. During perfusion 82 nmoles epoxycarbamazepine (E-CBZ) were formed, most of which were found in perfusion medium. Tissue levels of E-CBZ were between 0.3 and 2.8 nmoles/g wet weight. No dihydroxycarbamazepine (DH-CBZ) could be found. Pretreatment of the rats with phenobarbital neither influenced the uptake of CBZ into the brains nor increased the formation of E-CBZ significantly.

Effect of ketanserin on the kinetics of digoxin and digitoxin

The influence of the serotonin antagonist ketanserin on the kinetics of digoxin and digitoxin were evaluated in healthy volunteers. Subjects received a single intravenous dose of digoxin (1.25 mg) or of digitoxin (1.0 mg) on two occasions: once in the control state, and again during treatment with ketanserin, 40 mg twice daily. Ketanserin caused a prolongation of digoxin elimination half-life (50 versus 40 h) and reduction in clearance (2.4 versus 3.7 ml/min/kg), but differences were not significant. For digitoxin, ketanserin caused a small but significant (p less than 0.005) increase in volume of distribution (0.89 versus 0.78 L/kg), but no significant effect on half-life (7.0 versus 6.8 days), or clearance (0.063 versus 0.059 ml/min/kg). Thus, ketanserin coadministration is not likely to alter steady-state concentrations of digoxin or digitoxin during clinical use of these two digitalis glycosides.

Studies on the intracerebral metabolism of anticonvulsant drugs--I. Perfusion of primidone through the isolated brain of the rat

Primidone and phenobarbital (each 85 nmoles/ml were separately perfused through the isolated brain of the rat. After 5 min of perfusion similar amounts of primidone and phenobarbital were taken up into the brain; for both drugs the concentration ratio between brain and perfusion medium was about 0.2. However, after 2 hr of perfusion the mean concentration ratio for primidone was about 0.55; for phenobarbital it was about 0.9 thus indicating a better uptake of phenobarbital. In two regions (hypophysis, mesencephalon) the concentration of phenobarbital was significantly higher than in perfusion medium. During 2 hr of perfusion of primidone, substantial quantities of phenobarbital and PEMA were formed amounting to 1400 pmoles for each metabolite. The highest concentration of the metabolites was found in septum, hypothalamus, hypophysis and mesencephalon. The in situ metabolism of primidone in the intact brain was demonstrated for the first time.

Disposition of [4-14C]oestradiol-17 beta in the isolated perfused brain of the rat

[4-14C] Oestradiol-17 beta was perfused through isolated brains of male and ovariectomized female rats. Two different perfusion media were used. The uptake of oestradiol-17 beta was higher in female brains, the highest concentrations being found in the hypophysis and hypothalamus. Oestradiol-17 beta was metabolized to a greater extent by female brains, the most important metabolite being oestrone. Additionally, 2-hydroxyoestradiol-17 beta, 6 zeta-hydroxyoestradiol-17 beta, and 7 alpha-hydroxyoestradiol-17 beta were found; 7 alpha-hydroxyoestrone and another polar metabolite could not be definitely identified. Quantitatively, 2-hydroxylation was no more important than hydroxylation at C atom 6 or 7.

An improved method for perfusion of the isolated brain of the rat-influence of perfusion conditions and application of analeptic and anticonvulsant drugs

A method for the perfusion of the isolated brain of the rat with synthetic fluorocarbon emulsion is described. The functional states of the brains were investigated using biochemical, biophysical, and histological methods. After 4.5 h of perfusion, all brains were in excellent condition and comparable to the in vivo state. The influence of perfusion conditions on the viability of the brains was studied. Deep hypothermia was well tolerated; at 13 degrees the EEG exhibited a mean frequency of about 8 Hz, while the mean amplitude was about 40% lower than at 28 degrees or 36 degrees. Constant-pressure perfusion did not affect brain function, provided that the pressure amplitude was very slowly decreased. During application of pentylenetetrazole (PTZ) it was found that the threshold concentration of PTZ in the perfusion medium to induce epileptic seizure discharges was 0.13 mg/ml. However, after repeated application of PTZ, the threshold concentration decreased exponentially, indicating a kindling phenomenon. It could be shown that not PTZ as such, but the spike potentials provoked by PTZ, induced the kindling effect. This was inhibited by application of primidone or phenobarbital.

Simultaneous perfusion of [4-14C]oestriol and [6,9-3H2]oestriol 16 alpha-monoglucuronide through the isolated rat liver. II. Kinetic aspects

The uptake of [4-14C]oestriol by the isolated perfused rat liver is 3.8 times faster as compared to that of simultaneously perfused [6,9-3H2]oestriol 16 alpha-monoglucuronide. During perfusion the concentration of both radioactive oestrogens decreased exponentially in perfusion medium (apparent kel: 0.061 min-1 and 0.016 min-1, respectively). [6,9-3H2]Oestriol 16 alpha-monoglucuronide was metabolized only to a small extent; more than 92% was secreted unchanged into the bile where it was highly concentrated (1800 nmol/g). In contrast [4-14C]oestriol was extensively metabolized; it was mainly hydroxylated at C-atom 2, leading to a rapid increase in the concentration of 2-hydroxyoestriol in the perfused medium. This metabolite was quickly taken up by the liver during recirculation and subsequently either methylated or sulphated. 2-Hydroxyoestriol monosulphate was glucuronated to 2-hydroxyoestriol 16 alpha-monoglucuronide 3-sulphate, which was rapidly excreted into the bile. No double conjugate was formed when [6,9-3H2]oestriol 16 alpha-monoglucuronide was perfused; this is additional evidence for the correctness of the assumption that monoglucuronides cannot serve as precursors of sulphoglucuronides.

Simultaneous perfusion of [4-14C]oestriol and [6,9-3H2]oestriol 16 alpha-monoglucuronide through the isolated rat liver. I. Qualitative aspects

Equimolar concentrations of [4-14C]oestriol and [6,9-3H]oestriol 16 alpha-monoglucuronide were simultaneously perfused through isolated rat livers. Oestriol was hydroxylated to 2-hydroxyoestriol and 6 xi-hydroxyoestriol; 2-hydroxyoestriol was further methylated to 2-methoxyoestriol. Oxidoreduction of oestriol led to the formation of 16 alpha-hydroxyoestrone, 16-0xooestradio-17 beta and 16-epioestriol. In addition, two dehydroxylation products, namely oestrone and oestradiol-17 beta were found. The metabolites formed from oestriol were partly conjugated to monoglucuronides, monosulphates and sulphoglucuronides. About 80% of the oestriol perfused was hydroxylated at C-atom 2. Most of the 2-hydroxyoestriol formed was either methylated (about 37%) or sulphated (about 55%). Only small amounts (less than 2%) of the catecholoestrogens formed were methylated as well as sulphated. The 2-hydroxyoestriol monosulphates accumulated in the liver. After their conjugation with glucuronic acid, the double conjugates formed were immediately excreted into the bile. In fact, 2-hydroxyoestriol 16 alpha-monoglucuronide 2(3?)-monosulphate comprised by far the main biliary metabolite of [4-14C]oestriol, followed by oestriol 16 alpha-monoglucuronide and 2-methoxyoestriol 16 alpha-monoglucuronide. No triated sulphoglucuronides were detected, thus indicating that the monosulphates are the immediate precursors of the double conjugates. [6,9-3H2]Oestriol 16 alpha-monoglucuronide was metabolised only to a small extent. After its uptake into the liver more than 90% of this conjugate was secreted unchanged into the bile. The remaining part was hydrolysed; the oestriol liberated followed the same metabolic reactions as those found for [4-14C]oestriol. This indicates that the 16 alpha-glucuronide of oestriol is not metabolised to any appreciable extent.

Liver cirrhosis and oestrogen metabolism--perfusion studies with cirrhotic rat livers

1. Radioactive oestrone and oestradiol-17 beta were perfused through normal and cirrhotic livers of rats. Liver cirrhosis had been induced by a combined application of carbon tetrachloride and azathioprine. 2. The hepatic uptake of both oestrogens by cirrhotic livers was reduced; the uptake of oestrone was more affected than that of oestradiol-17 beta. 3. The pattern of oestrogen metabolites indicated a reduction of the sulphotransferase activity in cirrhotic livers. The activity of other enzymes of oestrogen metabolism were similar in normal and cirrhotic livers. 4. The amount of oestrogen glucuronides excreted into the bile was significantly less in cirrhotic livers although the bile volume was larger in cirrhotic than normal livers. 5. The release of oestrogen metabolites into the circulating medium was considerably higher during perfusion of cirrhotic livers. From the findings presented here it is concluded that the turnover of oestrogens is slower in cirrhotic than in normal livers. Moreover, it may be speculated that the distribution volume of the oestrogen metabolites is smaller in rats with liver cirrhosis, due to a disturbed enterohepatic circulation. This results in higher oestrogen concentrations in extracellular fluids, thus supporting the concept of hyper-oestrogenism in liver cirrhosis.

Reduced uptake of oestrone and corticosterone by cells from cirrhotic rat liver

The uptake of oestrone and corticosterone into isolated parenchymal cells from normal and cirrhotic rat livers has been studied. The maximal uptake of both hormones by cells from cirrhotic livers was reduced by 30 to 50 % compared to the uptake by normal cells. The affinity of the uptake systems for both hormones was similar in cells from normal and cirrhotic livers.

The activation energy for the uptake of oestrone by normal cells was 3.9 ± 0.2 kcal./mol from 0 to 40°C, whereas that for the uptake of oestrone by cells from cirrhotic rats was 3.0 ± 0.1 kcal./mol. Glucuronidation of oestrone by cells from cirrhotic livers was lower than that by cells from normal livers, but that by homogenates of the diseased tissue was not affected.

The Arrhenius plot of the uptake of corticosterone by normal cells showed a transition at 17°C; the activation energy for the uptake by normal cells was 16.0 ± 1.4 and 6.0 ± 0.7 kcal./mol from 0 to 17°C and 17 to 40°C, respectively. The activation energy for the uptake of corticosterone by cells from cirrhotic livers was 11.4 ±0.6 and 2.8 ± 0.2 kcal./mol from 0 to 17°C and 17 to 40°C, respectively. Sulfhydryl reagents reduced the uptake of both hormones by both cell preparations by 10 to 20 %; treatment of cells with β-galactosidase, phospholipase A and pronase reduced the uptake of both hormones. The results suggest that the amount of oestrone and corticosterone transported into isolated parenchymal cells from cirrhotic livers is decreased.

Studies on the metabolism of oestrone sulphate. Comparative perfusions of oestrone and oestrone sulphate through isolated rat livers

The metabolism of [4-(14)C]oestrone and of [6,7-(3)H(2)]oestrone sulphate was studied during cyclic perfusion and once-through perfusion of the isolated rat liver. The following results were obtained. 1. As shown by once-through perfusion, the two steroids are metabolized differently during the first passage through the organ. [4-(14)C]Oestrone was taken up by the liver and partly delivered as oestradiol-17beta and oestriol into the medium. After uptake of [6,7-(3)H(2)]oestrone sulphate, only oestrone, liberated by hydrolysis, was delivered into the medium; no oestradiol-17beta or oestriol could be detected in the medium after one passage through the organ. This indicates that intracellular oestrone, which was taken up as such, and oestrone, which derived from intracellular hydrolysis, may be metabolized in different compartments of the liver cell. 2. The results of the cyclic perfusion showed that intracellular oestrone is preferentially conjugated with glucuronic acid, and subsequently excreted into the bile. Intracellular oestrone sulphate is preferably reduced to oestradiol sulphate, thus indicating that oestrone sulphate is a better substrate for the 17beta-hydroxy steroid oxidoreductase than is oestrone. 3. Albumin-bound oestrone sulphate acts as a large reservoir, and in contrast with free oestrone is protected from enzyme attack by its strong binding to albumin. 4. Oestrone sulphate is partly converted into the hormonally active oestrone by liver tissue. This suggests that liver not only inactivates oestrogens, but also provides the organism with oestrone, which is subsequently readily taken up by other organs.

Effect of oxygen shortage on the metabolism of oestrone in the hemoglobin-free perfused rat liver

The isolated rat liver was perfused with a haemoglobin-free, albumin containing salt solution at 28 degrees and 37 degrees C, respectively, with [4-14C]oestrone as substrate. During perfusion, the functional state of the liver was checked by continuously measuring the oxygen pressure and hydrogen ion concentration in the perfusion medium, flow rate, oxygen tension at various areas of the liver surface, and oxygen consumption; in addition, the following biochemical parameters were determined: ATP, ADP, lactate and pyruvate in liver tissue, and lactate and pyruvate in the perfusion medium. After 30 min of perfusion, free steroids, steroid glucuronides, steroid sulphates and the remaining water-soluble metabolites, present in liver tissue, perfusion medium and bile, were separated from each other and characterised by thin-layer and paper chromatography. It was found that, during perfusion at 37 degrees C, less hydroxylated metabolites were formed than at 28 degrees C. In contrast, metabolites whose formation is not directly oxygen-dependent, such as glucuronides and sulphates, arose in higher amounts at 37 degrees C than at 28 degrees C. It may be concluded that the relative shortage of oxygen at 37 degrees C leads to a selective impairment of metabolic pathways requiring a sufficient supply of molecular oxygen. Since oxidative processes play an important role in the biogenesis and metabolism of steroid hormones, it is evident that results, obtained in perfusion experiments with haemoglobin-free media at 37 degrees C, must be treated with reserve.

Uptake of cortisol by isolated rat liver cells. A phenomenon indicative of carrier-mediation and simple diffusion

The uptake of cortisol by isolated rat liver cells was studied. Cortisol was taken up rapidly; the uptake increased with increasing temperature and reached a plateau after 45 s at 37 degrees, C, after 60 s at 27 degrees C, and after 90 s at 22 degrees C; at 5 degrees C the uptake increased linearly with time. The uptake was linear up to 1.5 mg of cell protein. Analysis of uptake as a function of increasing concentration of cortisol in the external medium indicated the presence of two saturable systems: a high-affinity system with an apparent Km value of 190 +/- 25 nM and a low-affinity system with an apparent Km value of 2200 +/- 180 nM. Above 600 nM, the rate of uptake of cortisol increased almost linearly with increasing cortisol concentration. Treatment of cells with KCN or 2,4-dinitrophenol inhibited the two saturable components, leaving the nonsaturable system unaffected. The affinity constants, Ka, were 6 X 10(6) M-1 and 0.6 X 10(6) M-1 for the high and low affinity components, respectively. These values increased approximately two-fold when uptake rates were corrected for diffusion. Cortisone and corticosterone inhibited the uptake of cortisol by liver cells competitively; dexamethasone inhibited cortisol uptake noncompetitively. Similarly, oestrone, oestradiol and testosterone decreased the uptake of cortisol, at a concentration of 2000 nM in the external medium, by 20, 49 and 35 percent, respectively; the inhibition was noncompetitive. p-Chloromercuribenzoate, N-ethylmaleimide and 1-fluoro-2,4-dinitrobenzene decreased the uptake of cortisol. Ouabain did not influence the uptake of cortisol; varying the external sodium concentration also did not affect uptake of cortisol. Cyclic-3',5'-adenosine monophosphate had a stimulatory effect. The results show that the first step, before cortisol is bound to intracellular binding proteins, is the uptake of cortisol by proteins in the plasma membrane. At lower concentrations of cortisol, uptake takes place by saturable processes; at higher concentrations saturation is not achieved, indicating that simple diffusion becomes the major route of transport into the cell. The proteins in the plasma membrane probably function as carriers to transport the glucocorticoid into the cell.

The effect of fluorocarbon FC 43 on the metabolism of steroids during perfusion of the isolated rat liver

The influence of fluorocarbon FC 43 on the metabolism of oestrogens in the isolated perfused rat liver was investigated. In comparative once-through perfusions with FC 43 emulsion or albumin solution as perfusion medium, the clearance rates of oestrone and its metabolites were determined. In perfusions with FC 43, the clearance of oestrone was lower, and the metabolites formed in the liver were more concentrated in the outflowing medium than in perfusions without fluorocarbon. This can be explained by the high affinity, even of conjugated oestrogens, to FC 43, which is established by equilibrium dialysis and partition coefficient. The results presented here show that the fluorocarbon has a strong influence of its own on the metabolism of steroids in the isolated perfused liver. Therefore, this solvent should be avoided as medium when the metabolism of steroids is studied in perfusion experiments.