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PubMed1976

Effects of dihydrogenated ergot alkaloids on the sleep-wakefulness cycle and on brain biogenic amines in the rat.

Investigations with four dihydrogenated ergot alkaloids, dihydroergotoxine, dihydroergonine, dihydroergostine and dihydro-beta-ergosine indicate that they exert similar dose dependent effects on the sleep-wakefulness cycle of the rat. The duration of wakefulness was increased, non-rapid eye movement (NREM) and, in particular, rapid eye movement (REM) sleep were shortened. 5-Hydroxytryptophan, but not apomorphine, induced similar changes of the rat sleep-wakefulness cycle. Neurochemical studies on rat brain biogenic amines indicate that dihydroergotoxine lowers homovanillic acid (HVA) levels and reduces HVA elevations after morphine or haloperidol in the striatum. In addition, the turnover of serotonin was slowed down and 5-hydroxyindoleacetic acid (5-HIAA) content in the whole brain was reduced. 5-HIAA elevation induced by clozapine was inhibited. These results suggest that the electroencephalographic changes in the rat produced by treatment with dihydrogenated ergot alkaloids reflect an enhanced level of vigilance and could be related to changes of brain biogenic amine metabolism.

Animals↗

PubMedDate not supplied

[Change in biogenic amine metabolism in botulin poisoning].

An increase in content of serotonin, histamine, the elevated histaminase activity in tissues and an increase in excretion of 5-hydroxyindolylacetic acid with urine were observed in experimental botulism, accompanied by paresis of sceletal muscles. As the paralysis progressed content of histamine gradually decreased in nervous tissue but it remained to be increased in the internal tissues although the histaminase activity was high. At the same time, content of serotonin was maintained at an increased level in the nervous tissue, but it was normalized in several internal organs. Excretion of 5-hydroxyindolylacetic acid with urine was decreased. LD50 of botulinic toxin was titrated in mice, which were simultaneously administered with preparations increasing or decreasing the synthesis and the activity of biogenic amines. The data obtained suggest that the impairments in metabolism of biogenic amines could be important for development of the intoxication.

Amine Oxidase (Copper-Containing)↗

PubMed1996

Involvement of biogenic amines and amino acids in the central regulation of cardiovascular homeostasis.

Biogenic amines and amino acids have been implicated in central cardiovascular homeostasis. Initially, drugs were injected into the brain and their effects on blood pressure were investigated. Other approaches allowed endogenous neurotransmitters released in the extracellular space of brain structures involved in cardiovascular regulation to be identified. As Nicolas Singewald and Athineos Philippu outline, even slight disturbances in blood pressure and/or isovolaemia lead to marked changes in the release rates of biogenic amines and amino acids in various brain structures. Blood pressure homeostasis is maintained with the participation of several brain regions and neurotransmitters which possess the same or opposing functions when released from CNS neurones.

Amino Acids↗

PubMedDate not supplied

Changes in circulatory biogenic amines during head-up tilt testing in neurocardiogenic syncope.

The pathogenesis of neurocardiogenic syncope is not completely understood. To examine the possible role of biogenic amines in patients with neurocardiogenic syncope, 18 consecutive patients (age 30 +/- 13 years, 15 males, 3 females) of unexplained syncope were subjected to Head-Up Tilt Testing (HUTT). Blood was sampled by an indwelling cannula at baseline, end of tilt test (or at syncope) and 1 min after returning to the supine position. Biogenic amines, epinephrine (E), norepinephrine (NE), serotonin (5-HT) and their metabolites, homovanillic acid (HVA) and 5-hydroxy indole acetic acid (5-HIAA), were measured in the serum after serial organic phase extraction by high-performance liquid chromatography (HPLC) using ultraviolet detection at a wavelength of 280 nm. Twelve patients were found to be HUTT negative while 6 patients were HUTT positive. Baseline E, NE and 5-HT levels were significantly greater in the HUTT positive patients [E 510 +/- 154 versus 302 +/- 96 pg/ml (p < 0.01), NE 253 +/- 99 versus 159 +/- 62 pg/ml (p < 0.05), 5-HT 174 +/- 32 versus 118 +/- 22 pg/ml (p < 0.01)]. E and HVA levels at the end of the test were significantly higher in HUTT positive patients [E 788 +/- 268 versus 465 +/- 119 pg/ml (p < 0.01), HVA 308 +/- 91 versus 112 +/- 12 pg/ml (p < 0.001)]. A significantly greater rise of E from the baseline was observed in HUTT positive patients (510 +/- 154 versus 112 +/- 12 pg/ml (p < 0.01)]. The increase in the levels of E and HVA both at baseline and after the tilt test, without a corresponding rise in NE levels indicates enhanced activity of the adrenomedullary axis which is not paralleled by NE release from sympathetic nerve endings in patients of neurocardiogenic syncope.

Adolescent↗

PubMed1998

[The influence of interferon therapy on CNS function--from the aspects of quantitative EEG and biogenic amines].

Various CNS side effects have been reported since interferon (IFN) was introduced for the treatment of chronic active hepatitis C (CAHC) patients. Most reports of EEG changes after IFN therapy were inspective, and there is no report of quantitative EEG analysis. In this study, changes in quantitative EEG and biogenic amines after IFN therapy were studied to enable identification of CNS side effects early in CAHC patients. Before and 7 days after IFN therapy, EEG records and plasma and urinary amines were examined in 36 CAHC patients (46.9 +/- 12.3 years, 29 men and 7 women) who were hospitalized for the IFN therapy. After IFN therapy, no notable change in biogenic amines was recognized. On EEG, 13 patients (39.4%) showed increased slow wave activities and 2 patients (6.1%) showed paroxysmal discharges after IFN therapy. On quantitative EEG, the patients showed significantly increased absolute power in slow alpha, theta and delta bands and decreased absolute power in fast beta band (paired-T test). After IFN therapy, 4 of 36 patients developed psychiatric disorders; 2 patients developed depressive symptoms and 2 other patients developed manic states. One depressive patient and one manic patient had 6 Hz spike and slow waves before IFN therapy. On quantitative EEG, the other manic patient had shown significantly increased absolute power in slow alpha and decreased power in fast alpha and beta bands, and the other depressive patient had shown significantly increased absolute power in fast theta band and decreased power in fast beta band before the development of the psychiatric disorders. These results suggest that the changes of quantitative EEG, between before and 7 days after IFN therapy, can be useful in assessing the risk for the development of psychiatric symptoms induced by IFN therapy. It also suggests that patients with slight EEG abnormality such as a 6 Hz spike and slow waves before IFN therapy need careful observation.

Adult↗

PubMedDate not supplied

[Biogenic amines in rat brain structures in an adjuvant arthritis model].

The role of changes in biogenic amines neurochemistry in cerebral structures in abnormal immunoreactivity accompanying development of autoimmune disease was investigated in experiments on 24 Wistar male rats. Biogenic amines and their metabolites (dopamine, dioxyphenylacetic acid, serotonin, oxyindolacetic acid) were assays in the sensomotor cortex, hypothalamus and hippocamp by means of high-performance liquid chromatography. Development of adjuvant arthritis was associated with definite neurochemical changes in the brain: inhibition of serotonin metabolism and enhancement of dopaminergic systems in the hypothalamus and sensomotor cortex. Prophylactic administration of oil solution D,L-alpha-tocopherol acetate promoted enhancement of serotonin metabolism in hypothalamic and hippocampal neurons. Bitemporal exposure to UHF electric field aroused stronger effects on the neurochemical metabolism in hypothalamic, hippocampal and sensomotor cortex neurons than TPA. It is concluded that bitemporal exposure to UHF electric field and antioxidant activate central immunoreactivity mechanisms in animals with adjuvant arthritis. Serotonin and dopamine systems in this process are leading.

Animals↗

PubMedDate not supplied

[Biogenic amines in the brain nuclei of August and Wistar rats under repeated stress].

The level of biogenic amines and their metabolites were measured in the brain regions involved in the major mechanisms of maintaining sympathetic and parasympathetic tones during emotional stress (48-h intermittent immobilization). An increase in 3,4-dihydroxyphenylalanine content and a trend to serotonin decrease were found in the locus coeruleus of Wistar rats, while in August rats an increase in noradrenaline, 3,4-dihydroxyphenylalanine, and 3,4-dihydroxyphenylacetic acid contents was observed in the same structure. In Wistar rats, a decrease in dopamine level was observed in the midbrain reticular formation and paraventricular hypothalamic nucleus against the background of the increased level of 3,4-dihydroxyphenylalanine in the ventral tegmental area. In August rats, an increase in 5-hydroxyindoleacetic acid was revealed in the dorsal nucleus of n. vagus, A1 and ventral tegmental areas, and nucleus tractus solitarii. The findings suggest that the level of biogenic amine metabolism in the structures of the central nervous system during emotional stress is determined genotypically.

Animals↗

PubMed1998

Studies of the biogenic amine transporters. VII. Characterization of a novel cocaine binding site identified with [125I]RTI-55 in membranes prepared from human, monkey and guinea pig caudate.

[125I]RTI-55 is a cocaine analog with high affinity for dopamine (DA) and serotonin (5-HT) transporters. Quantitative ligand binding studies revealed a novel high affinity [125I]RTI-55 binding site assayed under 5-HT transporter (SERT) conditions which has low affinity for almost all classic biogenic amine transporter ligands, including high affinity 5-HT transporter inhibitors such as paroxetine, but which retains high affinity for cocaine analogs. This site, termed SERT(site2) for its detection under 5-HT transporter conditions (not for an association with the SERT) occurs in monkey caudate, human caudate, and guinea pig caudate membranes, but not in rat caudate membranes. SERT(site2) is distinguished from the DA transporter (DAT) and SERT by several criteria, including a distinct ligand-selectivity profile, the inability to detect SERT(site2) in cells stably expressing the cloned human DAT, and insensitivity to irreversible ligands which inhibit [125I]RTI-55 binding to the DAT and SERT. Perhaps the most striking finding about SERT(site2) is that a wide range of representative antidepressant agents have very low affinity for SERT(site2). The affinity of cocaine for this site is not very different from the concentration cocaine achieves in the brain at pharmacological doses. Viewed collectively with the observation that ligands with high affinity for SERT(site2) are mostly cocaine analogs, these data lead us to speculate that actions of cocaine which differ from those of classic biogenic amine uptake inhibitors may be mediated in part via SERT(site2).

Animals↗

PubMed2000

Neurochemical neutralization of methamphetamine with high-affinity nonselective inhibitors of biogenic amine transporters: a pharmacological strategy for treating stimulant abuse.

The abuse of methamphetamine (METH) and other amphetamine-like stimulants is a growing problem in the United States. METH is a substrate for the 12-transmembrane proteins which function as transporters for the biogenic amines dopamine (DA), serotonin (5-HT), and norepinephrine (NE). Increased release of CNS DA is thought to mediate the addictive effects of METH, whereas increased release of NE in both the peripheral and CNS is thought to mediate its cardiovascular effects. The neurotoxic effects of METH on both dopaminergic and serotonergic nerves requires the transport of METH into the nerve terminals. Thus, transport of METH into nerve terminals is the crucial first step in the production of METH-associated pharmacological and toxicological effects. A single molecular entity which would block the transport of METH at all three biogenic amine transporters might function to neurochemically neutralize METH. This agent would ideally be a high-affinity slowly dissociating agent at all three transporters, and also be amenable to formulation as a long-acting depot medication, such as has been accomplished with an analog of GBR12909. As a first step towards developing such an agent, we established an in vitro assay which selectively detects transporter substrates and used this assay to profile the ability of a lead compound, indatraline, to block the releasing effects of METH and MDMA at the DA, 5-HT, and NE transporters. The major finding reported here is that indatraline blocks the ability of METH and MDMA to release these neurotransmitters. Synapse 35:222-227, 2000. Published 2000 Wiley-Liss, Inc.

Adrenergic Uptake Inhibitors↗

PubMed2005

Looking for biogenic magnetite in brain ferritin using NMR relaxometry.

Mammalian cellular iron is stored inside the multisubunit protein ferritin, normally taking the structure of a ferrihydrite-like mineral core. It has been suggested that biogenic magnetite, which has been detected in the brain and may be related to neurodegenerative diseases such as Alzheimer's and Parkinson's diseases, could initially form in ferritin. Indeed, as ferritin is present in the brain, the ferrihydrite core could be a precursor for biogenic magnetite formation--particularly in cases where the normal functioning of the ferritin protein is disrupted. In this work, NMR relaxometry was used to detect magnetite inside samples of ferritin extracted from normal and Alzheimer-diseased brains. The method was first calibrated with different fractions of horse spleen ferritin and synthetic magnetite particles. The relaxometry results suggest that the proportion of iron contained in brain ferritin in the form of well-crystallized magnetite instead of ferrihydrite must be <1%, which is much less than that reported for 'magnetite-like' phase in recent transmission electron microscopy studies of similar samples. Consequently, the magnetization of this 'magnetite-like' phase must be very low compared with that of magnetite.

Aged, 80 and over↗

PubMed1995

[Biogenic organochlorine compounds--occurrence, function and ecological relevance].

Organic chlorinated compounds are of increasing interest due to their almost ubiquitous occurrence in the biosphere, their toxic and cancerogenic activity, and their environmental relevance. Despite the relatively high level of knowledge on anthropogenic chlorine compounds, knowledge about biogenic chlorine compounds is comparatively poor. This is astonishing because the quantity of natural emissions of particular organic chlorinated compounds into the ecosphere exceeds that from industrial production considerably. An overview of the occurrence, biosynthesis, and ecological significance of biogenic chlorine-containing organics is given in this article. Results of recent investigations on this topic are discussed and the natural elimination processes of organic chlorinated compounds presented.

Bacteria↗

PubMed1999

Biogenic amines in foods: histamine and food processing.

Biogenic amines, e.g. histamine, occur in many different foods. At high concentrations, they are risk factors for food intoxication, whereas moderate levels may lead to food intolerance. Sensitive persons, with insufficient diamine oxidase activity, suffer from numerous undesirable reactions after intake of histamine containing foods. Besides spoiled foodstuffs, especially fermented foods tend to contain elevated levels of biogenic amines, although their concentrations vary extensively not only between different food varieties but also within the varieties themselves. High histamine content in foods and beverages result from microbial contamination. The evidence of enteral histaminosis represents a challenge for the food industry to produce foods with histamine levels as low as possible. We therefore investigated critical steps for histamine formation during food production processes, and established production methods that include low-histamine technology.

Food Analysis↗

PubMed2005

Biogenic stabilization of intertidal sediments: the importance of extracellular polymeric substances produced by benthic diatoms.

The sediment-stabilizing effect of benthic diatoms was investigated in a laboratory setting. Axenic cultures of the benthic diatoms Nitzschia cf. brevissima and Cylindrotheca closterium were inoculated in Petri dishes containing sand and incubated under axenic conditions. By ensuring aseptic routines throughout the experiments, interference from other organisms occurring with diatoms in natural photothrophic biofilms was avoided. This allowed the examination of the role of benthic diatoms in sediment stabilization. Increases in the critical erosion shear stress of the sediment were observed in the presence of both diatom taxa relative to sterile sediment. However, N. cf. brevissima was more effective than C. closterium. Values of critical shear stress in the experimental system were in the same range as those observed in natural biofilms, which indicates that diatoms are important agents for biogenic stabilization. Extracellular carbohydrate contents in the microcosms were similar for both diatom species. However, in the presence of N cf. brevissima, extracellular carbohydrate correlated significantly to critical shear stress, explaining up to 80% of the variation, whereas this was not the case for C. closterium. Therefore, it was concluded that the quantity of extracellular polymeric substances (EPS) alone did not explain the biogenic stabilization. Observed adsorption of EPS to sediment particles depended on the relative amount of uronic acids in the exopolymers. Using fluorescently labeled lectins, confocal laser scanning microscopy showed that EPS secretion by N. cf. brevissima resulted in ordered three-dimensional matrix structures. It is suggested that the structuring of EPS plays an prominent role in the process of biostabilization, and that diatoms such as N. cf. brevissima are actively involved in producing the structure of EPS, whereas others such as C. closterium do not do so to the same extent.

Adsorption↗

PubMed2002

Detection of biogenic CO production above vascular cell cultures using a near-room-temperature QC-DFB laser.

We report the first application of pulsed, near-room-temperature quantum cascade laser technology to the continuous detection of biogenic CO production rates above viable cultures of vascular smooth muscle cells. A computer-controlled sequence of measurements over a 9-h period was obtained, resulting in a minimum detectable CO production of 20 ppb in a 1-m optical path above a standard cell-culture flask. Data-processing procedures for real-time monitoring of both biogenic and ambient atmospheric CO concentrations are described.

Air Conditioning↗

PubMed2026

Biogenic Silver Nanoparticles from the Cell-Free Supernatant of Mychonastes sp. B1: Antibacterial and Antibiofilm Effects, and Wound Healing Activity Supported by Gene and Protein Expression Analysis.

The biogenic synthesis of silver nanoparticles (AgNPs) using microalgae provides a sustainable alternative to conventional physicochemical methods. In this study, AgNPs were synthesized from the cell-free supernatant of the freshwater microalga Mychonastes sp. B1 and characterized by ultraviolet-visible spectroscopy (UV-Vis), transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), and field-emission scanning electron microscopy with energy-dispersive X-ray spectroscopy (FE-SEM/EDS). The nanoparticles were predominantly spherical (15-55 nm), highly stable (ζ =  - 42.8 mV), and appeared to be capped by extracellular polymeric substances. The biogenic AgNPs (GS-AgNPs) exhibited potent antibacterial activity, with minimum inhibitory concentrations (MICs) of 2.0 µg/mL against Staphylococcus aureus and 2.5 µg/mL against Pseudomonas aeruginosa, and significantly (p < 0.05) inhibited biofilm formation. Fibroblast viability remained at or above 80% at AgNP concentrations up to 1.5 µg/mL, which promoted cell migration and increased wound closure by 8.1% at 24 h (p < 0.05). Exposure to 1.5 µg/mL AgNPs significantly upregulated extracellular matrix markers (Col1a1 2.3-fold, Fn1 3.3-fold at mRNA level; COL1A1 2.1-fold, FN1 2.7-fold at the protein level). These findings indicate that GS-AgNPs possess antimicrobial and wound healing properties, highlighting their potential as biocompatible nanomaterials for biomedical applications.

Silver↗

PubMed1991

Interference of biogenic amines with the measurement of proteins using bicinchoninic acid.

The use of bicinchoninic acid (BCA) to measure protein concentrations has received wide acceptance because the reagent is insensitive to many of the buffers, sucrose solutions and detergents used with various tissue and enzyme preparations. However, any compound capable of reducing Cu2+ in an alkaline medium such as biogenic amines will produce a color reaction. The primary objective of this study was to determine whether biogenic amines present in neuronal tissue would interfere with the measurement of protein using the BCA method. Catecholamines were found to produce a linear increase in color of the BCA reagent at concentrations between 1 and 100 nmol/2.1 ml assay volume. Catecholamines appeared to be more sensitive to the BCA reagent than either serotonin or ascorbic acid. Catecholamines at concentrations of 50 nmol/mg of protein or 1 nmol/2.1 ml assay volume or higher will produce significantly (P less than 0.0001) higher color reactions than protein alone. The BCA reagent is not ideal for measuring protein concentrations of intact synaptic vesicles and chromaffin granules since the catecholamine concentrations in these organelles are high enough to increase the color developed by 1.1 to 2.5 times that observed with protein alone. The linearity of the color development produced by catecholamines suggest that BCA could be used to quantitate catecholamine concentrations between 1 and 100 nmol. The BCA reagent will not distinguish between the different catecholamines.

Catecholamines↗

PubMed1986

Effects of induction of rat liver cytosolic aldehyde dehydrogenase on the oxidation of biogenic aldehydes.

Phenobarbital and tetrachlorodibenzo-p-dioxin (TCDD) induce two different forms of aldehyde dehydrogenase (EC 1.2.1.3, ALDH), designated phi and tau respectively, in the rat liver cytosol. The physiological substrates for these enzymes are as yet unknown. In this study we investigated whether the induction of these enzymes forms affected the metabolism of dopamine and norepinephrine in rat liver slices. A 10-fold increase in phi-ALDH produced by phenobarbital treatment resulted in small increases in the formation of 3,4-dihydroxyphenylacetic acid and 3,4-dihydroxymandelic acid from the biogenic amines. The 50- to 100-fold elevation of the tau-isozyme did not alter the rate of formation of the acids. When liver slices were incubated with 40 mM ethanol, the formation of the reduced products of dopamine and norepinephrine, 3,4-dihydroxyphenylethanol and 3,4-dihydroxyphenylglycol, respectively, was favored. Under these conditions, the induction of the phi-isoenzyme again produced only a small increase in the formation of the acid products, whereas the induction of the tau-isoenzyme had no effect on acid production from biogenic amine metabolism. The results suggest that neither the phi- nor the tau-forms of ALDH are involved in the hepatic metabolism of dopamine or norepinephrine and support the conclusion that the oxidation of the aldehyde derived from dopamine occurs in mitochondria [A. W. Tank, H. Weiner and J. Thurman, Biochem. Pharmac. 30, 3265 (1981)].

3,4-Dihydroxyphenylacetic Acid↗

PubMed1986

Formation of biogenic amines by isolated kidneys of spontaneously hypertensive rats.

Kidneys form dopamine (DA) from L-dopa and serotonin from L-5-hydroxytryptophan (L-5-HTP) via aromatic L-amino acid decarboxylase. We compared the ability of isolated perfused kidneys from adult (20-week-old) spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto rats (WKY) to form these biogenic amines. Renal vascular resistance (RVR) was greater in perfused kidneys from SHR (n = 10) than WKY (n = 8) (p less than 0.01). Slight decreases in RVR were observed during L-dopa infusion but these were unrelated to DA formation. L-Dopa infusion was associated with greater DA output in SHR than WKY in both the renal venous and urinary effluents although the latter did not achieve statistical significance. L-5-HTP increased RVR to a greater degree in SHR than WKY kidneys. This was associated with larger quantities of serotonin in the urinary and venous effluents and greater pressor responses to exogenous serotonin in SHR than WKY kidneys; however, either parameter alone was not significantly increased. Our findings do not support a deficiency of intrarenal DA formation as a pathogenic factor for hypertension in SHR. Biogenic amine formation is as great if not greater in SHR than WKY kidneys and appears to contribute largely to the greater increases in renal resistance seen in SHR kidneys on infusion of L-5-HTP. Enhanced renal serotonin formation may elevate blood pressure, whereas enhanced renal DA formation would favor blood pressure lowering, perhaps as a compensatory mechanism.

5-Hydroxytryptophan↗