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At least 343 records · Page 19Linked to original sources
PubMed2001

Biphasic effects of acetaldehyde-biogenic amine condensation products on membrane fluidity.

I have studied the effects of four acetaldehyde-biogenic amine condensation products on membrane fluidity of liposomes, consisting of 1-palmitoyl-2-oleoylphosphatidylcholine and cholesterol, by measuring fluorescence polarization using different probes. The condensation products were 1-methyl-1,2,3,4-tetrahydro-beta-carboline (MTBC), 6-hydroxy-1-methyl-1,2,3,4-tetrahydro-beta-carboline (6-OH-MTBC), 3-carboxy-1-methyl-1,2,3,4-tetrahydro-beta-carboline (3-C-MTBC) and 6,7-dihydroxy-1-methyl-1,2,3,4-tetrahydroisoquinoline (salsolinol). They changed the fluidity of the hydrophobic and hydrophilic regions of liposomal membranes at micromolar levels almost corresponding to their antibacterial and antiplatelet concentrations, but their membrane effects varied by structure, concentration and membrane lipid composition. MTBC and salsolinol showed biphasic effects on the inner layers of membranes to enhance the fluidity at 250-1000 microM and reduce the fluidity at 50-100 microM, whereas both of them fluidized the outer layers of the membranes. 3-C-MTBC concentration-dependently fluidized both layers of membranes. 6-OH-MTBC most weakly enhanced and reduced the fluidity of the outer and inner layers, respectively. The membrane effect of MTBC was the greatest of the four condensation products. MTBC (50-1000 nM) significantly reduced the fluidity by exclusively acting on the membrane core, but was less effective in fluidizing the membrane surface. However, the others were not active at low nanomolar levels. The membrane effects may be partly responsible for the antibacterial and antiplatelet actions of the acetaldehyde-biogenic amine condensation products, although they do not appear to be simple membrane fluidizers.

Acetaldehyde↗
PubMed2006

Changes in brain biogenic amines and haem biosynthesis and their response to combined administration of succimers and Centella asiatica in lead poisoned rats.

This study was designed to investigate the therapeutic potential of meso 2,3-dimercaptosuccinic acid (DMSA) and one of its monoesters, monoisoamyl DMSA (MiADMSA), individually or when administered in combination with an extract of Centella asiatica against experimental lead intoxication in rats. Biochemical variables indicative of alterations in the central nervous system and haem biosynthesis were investigated to determine the toxicity in male Wistar rats. Thirty five rats were exposed to 0.2% lead acetate for 10 weeks, followed by 10 days of treatment with DMSA and MiADMSA (50 mg kg(-1), i.p., once daily) alone and in combination with C. asiatica (200 mg kg(-1), p.o., once daily). Biochemical variables indicative of oxidative stress and brain biogenic amines, along with lead concentration in blood and brain, were measured. Lead exposure caused a significant depletion of blood and brain delta-aminolevulinic acid dehydratase (ALAD) activity, an important enzyme of the haem biosynthesis pathway, and glutathione (GSH) level. These changes were accompanied by a marked increase in reactive oxygen species (ROS) level, thiobarbituric acid reactive substances (TBARS), delta-aminolevulinic acid synthase (ALAS) and oxidized glutathione (GSSG) activity in blood and brain. Significant depletion of brain noradrenaline (norepinephrine, NE), 5-hydroxytryptamine (5-HT), dopamine (DA) and acetylcholinesterase (AChE) also were observed following lead exposure. Also seen was a significant depletion in brain glutathione peroxidase (GPx), glutathione S-transferase (GST) and monoamine oxidase activity, as well as blood and brain superoxide dismutase (SOD) activity. These biochemical changes were correlated with an increased uptake of lead in blood and brain. Combined administration of MiADMSA and C. asiatica was most effective in reducing these alterations, including biogenic amines, besides reducing body lead burden, compared with individual treatment with MiADMSA. Certain other biochemical variables responded favourably to combination therapy and monotherapy with MiADMSA. Thus, supplementation of C. asiatica during chelation could be recommended for achieving optimum effects of chelation therapy.

Animals↗
PubMed1982

Effects of brain biogenic amines on ethanol withdrawal reactions and the development of ethanol dependence in mice.

Mice were made physically dependent on ethanol by a four-day period of ethanol inhalation. A single injection of L-dopa tended to enhance ethanol withdrawal reactions and 5HTP tended to suppress it. Daily treatment with PCPA and L-dopa or pretreatment with 6OHDA tended to modify the severity of withdrawal reactions. PCPA slightly decreased the severity, 6OHDA tended to aggravate the severity, and L-dopa tended to decrease the severity. The simultaneous estimation of brain biogenic amine levels suggests that 5HT and DA may be involved in the development of physical dependence on ethanol. Treatment with neuropharmacological drugs during ethanol withdrawal modified the severity of ethanol withdrawal reactions. Pentobarbital and diazepam completely suppressed ethanol withdrawal reactions. GHBA and reserpine suppressed the severity and haloperidol, imipramine, and methylphenidate aggravated it. The simultaneous estimation of brain catecholamine levels suggests that suppression of ethanol withdrawal reactions consistently results from the decreased activities of either noradrenergic or dopaminergic neurons. However, the effects of biogenic amines on ethanol withdrawal reactions may be different from those on the development of physical dependence on ethanol.

Alcoholism↗
PubMed1989

Relationships between the effects of peripherally administered salmon calcitonin on calcaemia and brain biogenic amines.

The effects of s.c. administered salmon calcitonin on the biogenic amine neurotransmitters and metabolites were studied in discrete brain sections in order to evaluate the relationships between these central effects and the fall of serum calcium and to investigate the mechanisms of calcitonin-induced behavioral changes. The biogenic amines and metabolites were simultaneously determined by high-performance liquid chromatography with electrochemical detection in tissue samples obtained from rats treated with 10-80 MRC U/kg of the peptide. Some rats were pretreated with calcium lactate to inhibit the calcitonin-induced hypocalcaemia. Most of the effects, consisting of signs of serotonergic system activation, have been observed in the hypothalamus, accounting for some behavioral effects of the peripherally administered salmon calcitonin. It was speculated that the activation of the brain serotonergic system could result from two indirect and separate mechanisms: the first, which would involve enhanced serotonin synthesis, seemed to be facilitated by calcium availability. A second possible mechanism, which would involve enhanced serotonin release from the neurons, seemed to be mediated by the fall of calcium levels in the blood.

Animals↗
PubMed1991

Quality assurance for biogenic amines with authentic patient specimens.

The measurement of biogenic amines and metabolites is essential for diagnosis and follow-up of neural crest tumors. A Quality Assurance programme involving the distribution of urine specimens obtained from patients with neural crest and related tumors was conducted by the Australian Association of Clinical Biochemists' Working Party on Biogenic Amines in 1988. Fifty laboratories participated in the programme and measured a number of analytes with a variety of methods. These included high performance liquid chromatography with electrochemical detection (HPLC-EC), spectrophotometry, fluorescence, fluorescence polarization immunoassay (Abbott TDX) and gas chromatography--mass spectroscopy (GC-MS). The results of this survey indicated that fluorimetric methods for catecholamines are unreliable as they are subject to interference particularly by Labetalol. Twice as many laboratories utilized catecholamines rather than metanephrines for detection of pheochromocytoma. 5-HIAA appears to be the analyte measured with the least accuracy, particularly with spectrophotometric methods of analysis. Several laboratories would have failed to diagnose some neural crest tumors and need to improve their performance.

Biogenic Amines↗
PubMed1993

Effect of L-thyroxine and carbimazole on brain biogenic amines and amino acids in rats.

Effect of L-thyroxine and carbimazole on brain biogenic amines and amino acids content and circulating levels of thyroid hormones has been investigated in rats. L-thyroxine treatment caused marked elevation of 5-HT, histamine and glutamate along with the decline in the level of GABA whereas administration of carbimazole had a contrary effect on rat hypothalamus. Further, L-thyroxine administration also raised histamine as well as glutamate content and decreased GABA level in thalamic region of the rat brain but carbimazole treatment reduced 5-HT and glutamate content in this area of the rat brain. Similarly, cortical content of 5-HT and histamine also increased following L-thyroxine administration whereas carbimazole treatment lowered 5-HT, histamine and glutamate levels. Simultaneously, there was a considerable rise in the circulating levels of T3 and T4 in L-thyroxine-treated rats and a marked reduction in their levels in carbimazole-treated rats. There is a positive correlation between these amines and the thyroid hormone level. Thus, the results suggest that L-thyroxine and carbimazole administration cause marked alteration in biogenic amines and amino acids in rat brain, which may have an important role in the functioning of thyroid gland.

Amino Acids↗
PubMed2003

Biogenic amines in striatum of rats that had been treated with ethanol, and their brains later stored in different temperatures.

The purpose of this study was to investigate how ethanol pretreatment and storage temperatures of brain striatum affect levels of biogenic amines in this tissue. Adult Wistar male rats were injected with 25% ethanol (5.0 g/kg i.p.) while the control rats were administered i.p. with the same volume of saline. Two hours later the rats were decapitated, their brains removed, and the striatum separated. Each striatum was divided into three parts: one part was immediately frozen on dry ice and kept at -70 degrees C; a second fragment was kept in a household refrigerator (+4 degrees C); and the third fragment was kept at +22 degrees C. Twenty-four hours later, levels of DA, DOPAC, HVA, 3-MT, 5-HT, and 5-HIAA in the striatum were assayed by HPLC/ED. Immediately after decapitation; ethanol levels were assayed in the serum of ethanol-pretreated and saline-pretreated rats using gas chromatography. Our results indicate that levels of striatal DA, DOPAC, and HVA in saline-pretreated rats decreased significantly when the storage temperature of the striatum was raised from -70 degrees C, through +4 degrees C, to +22 degrees C, while levels of striatal 5-HT and 5-HIAA remained constant within the temperature range tested and levels of 3-MT fluctuated. In ethanol-pretreated rats, striatal levels of DOPAC, HVA, and 5-HIAA were increased in all three storage temperatures, while levels of DA, 5-HT, and 3-MT were decreased in those temperatures. Those decreases were most profound in striatal samples kept at +22 degrees C. We conclude that concern about possible interactions between drugs and biogenic amines should be exercised.

Animals↗
PubMed1992

Central and peripheral biogenic amine effects of brain missile wounding and increased intracranial pressure.

This study was performed to ascertain the acute effects of brain missile wounding on brain-stem and hypothalamic biogenic amines in a group of cats anesthetized with pentobarbital (40 mg/kg). Brain wounding is associated with a concomitant increase in intracranial pressure (ICP); to separate the effects of elevated ICP alone from the effects of wounding, a second group of cats had ICP artificially increased from a normal level of approximately 5 mm Hg to approximately 140 mm Hg by infusion of mock cerebrospinal fluid into the cisterna magna. In both groups, significant epinephrine depletions (47% to 74%) occurred in the nucleus tractus solitarius, area A1C1, locus ceruleus, raphe nuclei, and posterior hypothalamus. Epinephrine levels were also significantly decreased in the anterior hypothalamus in the wounded cats. In addition, both brain wounding and artificially induced ICP increases caused significant decreases of norepinephrine in the posterior hypothalamus, and of serotonin, 5-hydroxyindoleacetic acid, dopamine, and homovanillic acid in the raphe nuclei. Only brain wounding, however, caused significant reductions of norepinephrine, dopamine, and homovanillic acid in the nucleus tractus solitarius and area A1C1. The plasma catecholamine levels resulting from brain wounding or artificially induced ICP increases were dissimilar only in the amount of time required to attain maximum plasma levels, with the wounded animals responding faster. It is concluded that the hypothalamic and brain-stem biogenic amine changes resulting from either brain wounding or increased ICP alone are reflective of a stress response. Brain-stem distortion caused by brain wounding did not appear to be a factor and monoaminergic systems appeared to remain intact despite a severe and eventually lethal brain injury.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗
PubMed1993

Regional differences in the levels of biogenic amines and their metabolites in rat brain after tricyclic antidepressant treatments.

Changes in the levels of biogenic amines in different brain regions and the cerebrospinal fluid in rats were measured after acute or chronic treatment with tricyclic antidepressants. After single or 3 weeks' treatment with imipramine or desipramine, blocks of tissues were obtained from seven regions of the brain (frontal cortex, corpus striatum, hippocampus, thalamus, hypothalamus, substantia nigra and cerebellum) immediately after collection of the cerebrospinal fluid (CSF) from the cisterna magna. The concentrations of biogenic amines and their metabolites (norepinephrine, epinephrine, dopamine, 5-hydroxytryptamine (5-HT), dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA)) in brain tissues and the CSF were measured using the high performance liquid chromatography-electrochemical detection system (HPLC-ECD). Treatment with desipramine or imipramine caused major alterations in the concentrations of central norepinephrine or 5-HT and its metabolite, respectively. Brain regional responses were variable according to the kind of tricyclic antidepressants and the duration of treatment. It is noteworthy that chronic treatment with both desipramine and imipramine caused altered hippocampal concentrations of norepinephrine and/or 5-HT and its metabolites. Striatal DOPAC concentrations were also changed after acute or chronic treatment with both drugs. These results suggest that tricyclic antidepressants altered neurotransmission according to the brain region, and the hippocampal norepinephrine and 5-HT and/or the striatal dopamine may have a significant role for the expression of antidepressant action of tricyclic antidepressants.

Animals↗
PubMed1978

Biogenic amine-containing cells in the chicken lung.

Formaldehyde induced fluorescence was used to identify biogenic amine-containing cells in the adult chicken lung. Such cells, found in the parabronchial region, are sparsely distributed. There are at least two types of biogenic amine-containing cells in the lung: one type probably contains serotonin and the other a catecholamine. These cells might function as either a humoral or hormonal regulator of pulmonary ventilation and perfusion or as a receptor involved in control of breathing.

Animals↗
PubMed1998

Changes in biogenic amines and microbiological analysis in albacore (Thunnus alalunga) muscle during frozen storage.

Albacore specimens of extra quality were analyzed for their biogenic amine contents after 1, 3, 6, and 9 months of frozen storage at -18 degrees C or -25 degrees C. A high-performance liquid chromatography method involving a linear elution gradient was optimized for the identification and determination of putrescine, cadaverine, histamine, spermidine, and spermine in albacore tuna. Putrescine was the biogenic amine that showed the highest increase, reaching concentrations of 59.04 ppm (815% of the initial level) and 68.26 ppm (942% of the initial level) in the white muscle of albacore after 9 months of frozen storage at -18 and -25 degrees C, respectively. Cadaverine, histamine, and spermidine concentrations were below 3, 5, and 11 ppm, respectively, after 9 months of frozen storage, while spermidine underwent a significant decrease at both storage temperatures. Microbiological analysis confirmed the absence of species of Enterobacteriaceae in 75% of the albacore specimens after 9 months of frozen storage; coliforms were always below 3 CFU/g. The survival rate of the psychrotrophic microorganisms after 9 months of frozen storage at -25 degrees C was 4.6%, while 38.9 and 92.1% of the aerobic mesophiles present in the white muscle of albacore before freezing survived 9 months of storage at -18 and -25 degrees C, respectively.

Animals↗
PubMed2000

Histamine and biogenic amine production by Morganella morganii isolated from temperature-abused albacore.

Histamine-producing bacteria were isolated from albacore stored at 0, 25, 30, and 37 degrees C. They were screened using Niven's differential medium, and their histamine production was confirmed by high-pressure liquid chromatography analysis. The optimum temperature for growth of histamine-producing bacteria was 25 degrees C. The bacterium producing the highest level of histamine was isolated from fish abused at 25 degrees C. It was identified as Morganella morganii by morphological, cultural, biochemical, and antimicrobial characteristics and by the Vitek microbial identification system. The M. morganii isolate was inoculated into tuna fish infusion broth medium, and the effect of temperature was determined for microbial growth and formation of histamine and other biogenic amines. The isolate produced the highest level of histamine, 5,253 ppm, at 25 degrees C in the stationary phase. At 15 degrees C, histamine production was reduced to 2,769 ppm. Neither microbial growth nor histamine formation was detected at 4 degrees C. To determine whether the isolate can also produce other biogenic amines that can potentiate histamine toxicity, production of cadaverine, putrescine, serotonin, tryptamine, tyramine, phenylethylamine, spermidine, and spermine by the isolate was also monitored. Cadaverine, putrescine, and phenylethylamine were detected with microbial growth in the tuna fish infusion broth medium. The optimum temperature for cadaverine, putrescine, and phenylethylamine formation was found to be 25 degrees C, as it was for histamine.

Animals↗
PubMed2002

Growth of Carnobacterium divergens V41 and production of biogenic amines and divercin V41 in sterile cold-smoked salmon extract at varying temperatures, NaCl levels, and glucose concentrations.

A complete factorial design 2(3) was used to study some aspects of Carnobacterium divergens V41 metabolism (growth, biogenic amine production, and divercin V41 production) in sterile cold-smoked salmon extract (SSE) at varying temperatures (3 to 9 degrees C), NaCl levels (2.5 to 6.5%), and glucose concentrations (2 to 6 g liter(-1)). The results showed that temperature and NaCl content were the most influential factors on growth parameters in SSE. Predictive models are suggested for the assessment of C. divergens lag time (t(lag)) and maximum specific growth rate (micro(max)) Among the biogenic amines studied, only tyramine was found to be produced by C. divergens in SSE. Furthermore, we showed that temperature, NaCl, and glucose variations did not greatly affect tyramine and divercin V41 production by the bacteria under the experimental conditions used. Indeed, divercin V41, a bacteriocin from C. divergens V41 that is highly active against some Listeria strains, was produced in SSE even under harsh culture conditions. Similarly, tyramine production in SSE was delayed at 3 degrees C but reached 35 microg ml(-1) in all experiments after 27 days of storage. However, this final tyramine concentration in SSE is low compared with the threshold values of 100 to 800 microg g(-1) reported as the potentially toxic dose in foods. Thus, we have found that C. divergens V41 is a promising strain for the biopreservation of refrigerated cold-smoked salmon.

Animals↗
PubMed2002

Formation of biogenic amines in a typical semihard Italian cheese.

Given that the concentration of biogenic amines in cheeses depends on variety, age, and type of microflora, a study was undertaken to investigate the formation of these compounds during the ripening of a typical semihard Italian cheese. Tryptamine, phenylethylamine, putrescine, cadaverine, histamine, and tyramine contents were calculated in 30 samples of Montasio cheese characterized by different levels of proteolysis. Histamine and tyramine were the major amines. Tryptamine and phenylethylamine concentrations were very low at all ripening periods. Putrescine and cadaverine were present only in samples with anomalous fermentation processes. The relationship between the total amine content and the proteolytic maturation coefficient was calculated; however, even for higher levels of proteolysis, the biogenic amine content in Montasio cheese was below the level considered potentially toxic.

Amino Acids↗
PubMed2004

Effects of on-board and dockside handling on the formation of biogenic amines in mahimahi (Coryphaena hippurus), skipjack tuna (Katsuwonus pelamis), and yellowfin tuna (Thunnus albacares).

Consumer illnesses by scombroid poisonings have been a continuing problem for many years. The intoxications follow the ingestion of fish such as tuna and mahimahi that have undergone bacterial decomposition, leading to the formation of biogenic amines. Research studies have concluded that histamine is one of the indicators of scombrotoxic fish and that other amines, such as cadaverine, could be involved in the illnesses. Guidance for the handling of fish on board fishing vessels to prevent the production of scombrotoxic fish has been limited by a lack of data addressing changes that occur in fish from the water to delivery at dockside. In this study, the changes in selected biogenic amines were determined in mahimahi and tuna, which were captured and held in seawater at 25 to 35 degrees C for incubation times up to 18 h. The fillets from the treated fish were sectioned by transverse cuts and analyzed for histamine, cadaverine, and putrescine. Results showed that at 26 degrees C, more than 12 h of incubation were required before a histamine concentration of 50 ppm was reached in mahimahi. At 35 degrees C, 50 ppm histamine formed within 9 h. Similar results were found for skipjack and yellowfin tuna. Histamine concentrations exceeded 500 ppm within an additional 3 h of incubation in mahimahi. At both temperatures, an increase in the concentration of cadaverine preceded an increase in histamine levels. Changes in putrescine concentrations in the fish were less pronounced. The study also demonstrated that histidine decarboxylase activity was retained in some frozen samples of fish and could result in further increases in histamine on thawing.

Animals↗
PubMed2004

Biogenic amines in restructured beef steaks as affected by added walnuts and cold storage.

This article evaluates changes in biogenic amines and how these relate to microbiological growth in chilled, fresh restructured beef steaks containing transglutaminase as a cold binding agent and different amounts of walnut. Added walnut and chilling favored higher total and lactic acid bacteria counts during storage, whereas Enterobacteriaceae were not affected. The highest initial biogenic amine concentrations were identified as spermidine, spermine, and tyramine. Both added walnut and cold storage generally favored the formation of amines (tyramine, histamine, putrescine, and cadaverine), which was more obviously apparent by the end of the storage period. Agmatine, on the other hand, was not generally affected by the walnut.

Animals↗
PubMed2006

Production of biogenic amines by lactic acid bacteria: screening by PCR, thin-layer chromatography, and high-performance liquid chromatography of strains isolated from wine and must.

Biogenic amines are frequently found in wine and other fermented food. We investigated the ability of 133 strains of lactic acid bacteria isolated from musts and wines of different origins to produce histamine, tyramine, and putrescine. We detected the genes responsible for encoding the corresponding amino acid decarboxylases through PCR assays using two primer sets for every gene: histidine decarboxylase (hdc), tyrosine decarboxylase (tdc), and ornithine decarboxylase (odc); these primers were taken from the literature or designed by us. Only one strain of Lactobacillus hilgardii was shown to possess the hdc gene, whereas four strains of Lactobacillus brevis had the tdc gene. None of the Oenococcus oeni strains, the main agents of malolactic fermentation, was a biogenic amine producer. All PCR amplicon band-positive results were confirmed by thin-layer chromatography and high-performance liquid chromatography analyses.

Base Sequence↗
PubMed1976

[Effect of the enterotropic carcinogen 1,2-dimethylhydrazine on the level of biogenic amines in the hypothalamus of rats].

The hypothalamic levels of noradrenaline (NA), dophamine (DA), serotonine (5-HT), 5-hydroxyindolacetic acid (5-HIAA) were found to be decreased in male rats 24 hours after subcutaneous injection of 1,2-dimethylhydrazine (SDMH) in a dose of 21 mg/kg. During 3 to 12 hrs after the SDMH treatment the hypothalamic level of NA was decreased, whereas the 5-HT turnover became greater. The hypothalamic histamine level increased 30 min after the SDMH injection only. In the brain stem and the great hemispheres the biogenic amine level displayed no significant changes under the effect of SDMH. The endocrine-metabolic changes due to the selected SDMH effect on the hypothalamic biogenic amine level are supposed to be of great significance in the realization of the carcinogenic action of SDMH in rats.

Animals↗