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1.
Serum and erythrocyte levels of the polyamines spermine, spermidine and putrescine, as well as ornithine decarboxylase in erythrocytes, were studied in patients with different neoplasms (breast, lung and colon cancer) and in those with a nonmalignant proliferative disease (familial polyposis). The blood levels of polyamines and the spermine/putrescine ratio were significantly higher in all tumors and in nonmalignant colon polyposis. In erythrocyte ornithine decarboxylase activity, spermine and spermidine levels, as well as spermidine/putrescine and spermine/putrescine ratios showed a significant decrease after surgery and chemotherapy. Our data suggest that high levels of blood polyamines and erythrocyte ornithine decarboxylase activity are related to cell proliferation and cancer treatment, but that levels of polyamines in serum and erythrocytes are still significantly high after cancer treatment and are similar to those in polyposis disease. Polyamines are related to nuclear activity during differentiation; therefore, the altered turnover of polyamines could be a sign of abnormal nuclear function. Since polyamines stimulate protooncogene expression, their high levels could be considered an important cofactor in malignant cell transformation.  相似文献   

2.
Recent studies have implicated alterations in the expression of polyamine-related genes in the brains of suicide completers including widespread downregulation of spermidine/spermine N1-acetyltransferase, the key enzyme in polyamine catabolism, suggesting compensatory mechanisms attempting to increase brain levels of polyamines. Given the complexity of the polyamine system, quantification of the levels of the polyamines is an essential step in understanding the downstream effects of dysregulated gene expression. We developed a method using high-resolution capillary gas chromatography (GC) in combination with mass spectrometry (MS) for quantitation of polyamines from post-mortem brain tissue, which allowed us to accurately measure spermidine and putrescine concentrations in post-mortem brain tissues. Using this method, we analyzed putrescine and spermidine levels in a total of 126 samples from Brodmann areas 4, 8/9, and 11, from 42 subjects, comprising 16 suicide completers with major depression, 13 non-depressed suicide completers, and 13 control subjects. Both putrescine and spermidine levels fell within the expected nanomolar ranges and were significantly elevated in the brain of suicide completers with a history of major depression as compared with controls. These results were not accounted by possible confounders. This is the first GC–MS study to analyze the expression of putrescine and spermidine from post-mortem brain tissue and confirms the hypothesis raised by previous studies indicating alterations in putrescine and spermidine levels in suicide/major depression.  相似文献   

3.
Administration of allylglycine to mice (.8 nmole/kg, 1. p.) results in a depletion of GABA levels, and it is accompanied by a decrease in SAM-DC activity and spermidine and spermine levels (Pajunen et al., 1979). Here we describe a biphasic effect on the acetylation of putrescine and spermidine in mouse brain homogenate. There appears to be an inverse correlation between the initial decrease in spermidine levels at 2 hours and the increase in the acetylation of spermidine. This is suggestive of a conversion of spermidine, probably through N -acetylspermidine to putrescine. The peak of putrescine acetylation observed by us at 4 hours may also reflect a conversion of putrescine, via acetylputrescine to GABA. The inter conversion hypothesis is supported by the fact that putrescine levels remain essentially stable in spite of a significant depletion of spermidine and spermine. In addition, there is a decrease in putrescine and spermidine acetylation at 8 hours, which coincides with the increase in ODC activity and the increase towards control levels of GAD activity (Pajunen et al., 1979). Such inverse correlations suggest a mechanism for replenishment of polyamines once GAD activity returns to control levels.  相似文献   

4.
Administration of allylglycine to mice (.8 mmole/kg, i.p.) results in a depletion of GABA levels, and it is accompanied by a decrease in SAM-DC activity and spermidine and spermine levels (Pajunen et al., 1979). Here we describe a biphasic effect on the acetylation of putrescine and spermidine in mouse brain homogenate. There appears to be an inverse correlation between the initial decrease in spermidine levels at 2 hours and the increase in the acetylation of spermidine. This is suggestive of a conversion of spermidine, probably through N1-acetylspermidine to putrescine. The peak of putrescine acetylation observed by us at 4 hours may also reflect a conversion of putrescine, via acetylputrescine to GABA. The interconversion hypothesis is supported by the fact that putrescine levels remain essentially stable in spite of a significant depletion of spermidine and spermine. In addition, there is a decrease in putrescine and spermidine acetylation at 8 hours, which coincides with the increase in ODC activity and the increase towards control levels of GAD activity (Pajunen et al., 1979). Such inverse correlations suggest a mechanism for replenishment of polyamines once GAD activity returns to control levels.  相似文献   

5.
Johnson DR  Guo GL  Klaassen CD 《Toxicology》2002,176(3):209-219
The naturally occurring polyamines--putrescine, spermidine and spermine--are organic cations present in all living cells and essential for cell growth and differentiation. The aim of the present study was to extend the investigations on the effects of porphyrinogenic compounds on polyamine metabolism. This was achieved by studying putrescine, spermidine and spermine levels in a model of acute porphyria, i.e. 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induced porphyria, and in a model of non-acute porphyria, i.e. hexachlorobenzene (HCB)-induced porphyria. HCB administration to female Wistar rats for 7, 14, 21, 28 and 56 days did not alter polyamine levels in liver, even though rats presented clear signs of HCB-induced porphyria. In contrast to HCB, DDC treatment resulted in a remarkable increase in putrescine levels in the liver of female and male Sprague-Dawley rats. This increase was due, at least in part, to ornithine decarboxylase (ODC) activation. DDC induction of putrescine levels did not show organ specificity, since it could also be seen in adrenal gland. Interestingly, the deregulation of polyamine biosynthesis occurred concomitantly with the deregulation of the heme biosynthetic pathway. In addition to porphyria, it is known that DDC intoxication affects several proteins of the hepatocyte cytoskeleton. It is suggested that DDC-induced increase in ODC activity and putrescine levels may be an early event contributing to alter the cytoskeleton.  相似文献   

6.
Recent evidence suggests that polyamines putrescine, spermidine and spermine are essential in maintaining normal cellular function. The present study investigated the effects of chronic treatment of difluoromethylornithine (DFMO, 3% in drinking water), a potent inhibitor of putrescine synthesis, for 54 consecutive days on animals'behavior and neurochemical levels in the CA1, CA2/3 and dentate gyrus sub-regions of the hippocampus and the prefrontal cortex. The DFMO group showed performance impairments in the place navigation and the probe test conducted 24 h after the training in the reference memory version of the water maze task, but not in the elevated plus maze, open field, object recognition, cued navigation and the working memory version of the water maze task when compared to the control group (drinking water only). DFMO treatment resulted in approximately 80-90% and 20% of reductions in the putrescine and spermidine levels, respectively, in the four brain regions examined, and a small reduction in agmatine level in the CA2/3, with no effects on spermine, glutamate and γ-aminobutyrate. The DFMO group showed decreased body weight relative to the control one. However, there were no significant differences between groups in the normalized brain, kidney and liver weights. The present study demonstrates that chronic treatment of DFMO depletes putrescine and decreases spermidine levels in the brain, inhibits growth, and impairs spatial learning and memory in the reference memory version of the water maze specifically. These findings merit further investigation to fully understand the functional role of endogenous polyamines in learning and memory.  相似文献   

7.
The naturally occurring polyamines, putrescine, spermidine and spermine, and the analogue cadaverine, induce a dose-dependent histamine release from rat peritoneal mast cells. Spermine was the most active among these polycationic metabolites, followed by spermidine and putrescine. The histamine release was inhibited by a 2 h pretreatment of the cells with pertussis toxin (100 ng/ml), demonstrating the involvement of a pertussis toxin-sensitive GTP-binding regulatory protein during the exocytotic process. Experiments performed with purified Go/Gi proteins reconstituted into phospholipid vesicles showed a direct stimulation of GTPase activity by the polyamines. This direct stimulation of G proteins and the consequent activation of the coupled effectors may represent a new mechanism of action for natural polyamines controlling receptor-dependent processes.  相似文献   

8.
INTRODUCTION: An efficient and reproducible electron-capture gas chromatographic protocol that allows the simultaneous detection and quantification of the polyamines putrescine (1,4-diaminobutane), cadaverine (1,5-diaminopentane), and spermidine (N-[3-aminopropyl]-1,4-diaminobutane) was developed. METHODS: Hepatic tissue from male Sprague-Dawley rats was used for analysis. The polyamines and the internal standard (sertraline) were extracted and derivatized with pentafluorobenzoyl chloride (PFBC) under basic aqueous conditions prior to analysis on a gas chromatograph equipped with a capillary column (narrow-bore fused silica column; 25 mm x 0.32 mm) and an electron-capture detector. RESULTS: PFBC reacts with the amine functions of the polyamines examined here to produce PFB derivatives with high sensitivity on electron-capture detection. The method permitted the quantitative analyses of all three amines in rat hepatic tissue; the concentration of putrescine, but not spermidine, was increased significantly following a 14-day administration of the diamine oxidase (DAO) inhibitor aminoguanidine. Cadaverine was also present at increased concentrations in hepatic homogenates from aminoguanidine-treated rats. DISCUSSION: Extractive derivatization with PFBC followed by gas chromatographic analysis using electron-capture detection results in a rapid and reproducible assay that permits the simultaneous detection and quantification of putrescine, cadaverine, and spermidine in biological tissue.  相似文献   

9.
Pretreatment of 17-day-old chick embryos with 2-diethylaminocthyl-2,2-diphenylvalerate hydrochloride (SKF 525-A) resulted in enhancement of hepatic δ-aminolevulinic acid (ALA)-synthetase activity and porphyrin accumulation induced by 3.5-diethoxycarbonyl-1,4-dihydro-2,4,6-trimethylpyridine (DDC). The levels of [14C]DDC and its metabolites in chick embryo livers were measured at different times after administration of [14C]DDC in the presence and absence of SKF 525-A. It is concluded that the magnitude of inhibition of DDC metabolism following SKF 525-A pretreatment is too small to account for the enhanced inducing effects of DDC. DDC was found to inhibit ferrochelatase in chick embryo liver at doses considerably less than those required to induce ALA-synthetase activity. A dose of DDC was selected for administration to the chick embryo large enough to produce 95 per cent inhibition of ferrochelatase without affecting ALA-synthetase activity. When SKF 525-A was then administered, a marked synergistic effect was observed on ALA-synthetase activity and porphyrin accumulation. It is concluded that DDC, by inhibiting ferrochelatase, enhances the ability of SKF 525-A to induce ALA-synthetase activity and porphyrin accumulation.  相似文献   

10.
Experimental pancreatitis is associated with activation of polyamine catabolism. The polyamine analog bismethylspermine (Me(2)Spm) can ameliorate pancreatic injury. We investigated the roles of polyamine catabolism in remote organs during pancreatitis and explored the mechanism of polyamine catabolism by administering Me(2)Spm. Acute pancreatitis was induced by an infusion of 2 or 6% taurodeoxycholate before Me(2)Spm administration. Blood, urine and tissues were sampled at 24 and 72 h to assess multi-organ injury and polyamine catabolism. The effect of Me(2)Spm on mortality in experimental pancreatitis was tested separately. Liver putrescine levels were elevated following liver injury. Me(2)Spm increased the activity of spermidine/spermine N(1)-acetyltransferase (SSAT) and depleted the spermidine, spermine or putrescine levels. Lung putrescine levels increased, and SSAT and spermine decreased following lung injury. Me(2)Spm enhanced the activity of SSAT and decreased the spermidine and spermine levels. Renal injury was manifested as an increase in creatinine or a decrease in urine output. Decreases in kidney SSAT, spermidine or spermine and an increase in putrescine were found during pancreatitis. In the 2% taurodeoxycholate model, Me(2)Spm decreased urine output and raised plasma creatinine levels. Me(2)Spm increased SSAT and decreased polyamines. Excessive Me(2)Spm accumulated in the kidney, and greater amounts were found in the 6% taurodeoxycholate model in which this mortality was not reduced by Me(2)Spm. In the 2% taurodeoxycholate model, Me(2)Spm dose-dependently induced mortality at 72 h. Like pancreatic injury, remote organ injury in pancreatitis is associated with increased putrescine levels. However, Me(2)Spm could not ameliorate multi-organ injury. Me(2)Spm administration was associated with significant renal toxicity and induced mortality, suggesting that the current dose is too high and needs to be modified.  相似文献   

11.
The diamine, putrescine, and polyamines, spermidine and spermine, are low molecular weight organic cations with documented regulatory roles in cell growth and differentiation. Multiple lines of direct and indirect evidence suggest that these organic cations also may function in stimulus-response coupling processes regulating cellular injury and repair. For example, recent studies in monocrotaline-treated rats, hyperoxic rats, and in cultured pulmonary endothelial cells suggest that polyamines regulate pulmonary endothelial integrity and may thus participate in development and/or regression of acute edematous lung injury. To determine if the polyamines are involved in a well-characterized animal model of acute lung injury, the present experiments assessed the relation between changes in polyamine synthesis and development of edema in lungs from rats treated with alpha-naphthylthiourea (ANTU). ANTU caused dose- and time-dependent increases in the lung activity of the initial and rate-limiting enzyme in polyamine biosynthesis, ornithine decarboxylase (ODC) and in the lung contents of the polyamines putrescine, spermidine, and spermine. ANTU also caused dose- and time-dependent increases in the lung wet-to-dry weight ratio indicative of pulmonary edema formation. Changes in lung polyamine biosyntheic activity after ANTU did not relate temporally to changes in the lung wet-to-dry weight ratio: ODC activity was depressed during the 3-h period immediately following ANTU administration, a period when the wet-to-dry weight ratio was increasing, and markedly elevated at 18 h after ANTU administration when the wet-to-dry weight ratio had returned to control levels. Pretreatment of the animals with alpha-difluoromethylornithine, a highly specific inhibitor of ODC, failed to attenuate ANTU-induced increases in lung wet-to-dry weight ratio. These observations indicate polyamine synthesis is enhanced in rat lungs with ANTU-induced pulmonary edema but, unlike certain other models of lung injury and pulmonary edema, accumulation of polyamines probably is not essential for development of edematous lung injury. It is conceivable that in this animal model polyamines play a role in lung repair processes or some longer-term consequence of lung injury.  相似文献   

12.
BACKGROUND: We have previously reported the polyamine uptake kinetics in various prostate and non-prostate cancer cell lines, concluding that the prostate cancer cell lines took up and accumulated polyamines at higher levels than non-prostate cell lines, with a view to their use as PET agents. The objective of the present study was to assess their in vivo accumulation in a rat prostate tumor model. MATERIALS AND METHODS: A comparative biodistribution study of the polyamines was conducted in AT3B-1 prostate tumors in male Copenhagen rats to determine which of the polyamines show preferential accumulation in the tumor. Tissue samples were collected one hour post administration of the polyamines (i.v.), and the radioactivity of the samples was measured by first combusting the tissue samples in a biological oxidizer and then assaying the trapped 14CO2 in a liquid scintillation counter. RESULTS: Putrescine exhibited the highest tumor accumulation followed by ornithine (4.1% and 1.8% of injected dose/g of the tumor respectively). The tumor-to-blood ratio was highest with putrescine followed by spermidine (18.7 and 12.9 respectively) and the order of tumor-to-normal prostate accumulation ratio was putrescine>ornithine>spermine>spermidine. CONCLUSION: The results indicated preferential accumulation of putrescine and ornithine in the prostate tumor.  相似文献   

13.
The induction of hypertrophy of cardiac and skeletal muscles has been studied after treatment with two different salbutamol dosages, therapeutic and doping. Treatment of rats subjected to a physical training schedule with repeated doses (16 μg kg?1 per day or 3 mg kg?1 per day) of salbutamol, a specific β-adrenergic agonist, induced a marked increase in both skeletal and heart-muscle weight, whereas total body weight did not change significantly. Adrenergic involvement of salbutamol-linked muscle hypertrophy was demonstrated by co-administration of the non-specific β-adrenergic antagonist, propranolol (20 mg kg?1 per day). Salbutamol-induced muscle hypertrophy was associated with an increase in serum, skeletal-muscle and heart levels of the naturally occurring polyamines putrescine, spermidine and spermine. These observations suggest the involvement of polyamines in muscle hypertrophy and the possible role of blood polyamines as exposure biomarkers in β-adrenergic-muscle hypertrophy.  相似文献   

14.
15.
The abilities of the naturally occuring polyamines, putrescine, spermidine and spermine, to affect variables related to the bioenergetic functions of isolated rat liver mitochondria were studied. At concentrations comparable to those present intracellularly, the polyamines inhibited state 4 respiration, but they had much less effect on state 3 or uncoupled respiration. The concentrations required to produce 25% inhibition (I25) of state 4 respiration varied according to the polyamine, with putrescine being least effective (I25, 20mM) and spermidine and spermine being more effective and comparable (I25, 7.5 and 7.0mM respectively). This inhibition was antagonized by 15 mM potassium and enhanced by valinomycin and 4 mM magnesium. Inhibition of monoamine oxidase, an enzyme of outer mitochondrial membrane, was also observed to occur. Addition of polyamines to mitochondrial suspensions caused an increase in the optical density and protected against the swelling effects of sublytic concentrations of Triton X-100. By electron microscopy, polyamines were found to cause the outer mitochondrial compartment to collapse bringing the inner and outer membranes into apparent contact with one another. The electrophoretic mobility of mitochondria toward the anode was markedly slowed by polyamines (i.e. 50% by 1.25 mM spermine), indicating surface binding and neutralization of the negative surface charge. In almost all of the above mitochondrial effects, spermine and spermidine were similar in effectiveness and putrescine was less effective. It is suggested that polyamines may be capable of modulating respiration of isolated mitochondria by binding to non-specific anionic sites at the surface of the inner mitochondrial membrane. Neutralization of the net negative surface potential may interfere with cation fluxes across the membrane, particularly those of potassium.  相似文献   

16.
The pulmonary uptake and accumulation of the three polyamines in intact, ventilated, and perfused rabbit lungs was investigated. Lungs were perfused using Krebs-Ringer bicarbonate buffer with albumin in which putrescine, spermidine, or spermine were included at an initial concentration of 10(-3), 10(-2), 10(-1), 5, 10, or 20 mM. At a 5 mM concentration of spermidine and spermine, the uptake by isolated lungs reached a steady state equilibrium in 20-30 min of perfusion. This did not occur for putrescine, which showed linear uptake throughout the entire period of the 60-min perfusion. The lung uptake of putrescine for all perfusate concentrations was greater than that of spermidine or spermine, but all three showed concentration-dependent linear uptake. In the presence of harmaline (1 mM) and ouabain (1 mM), isolated perfused rabbit lungs showed a decrease in uptake of putrescine although no effect was seen for spermidine and spermine. Perfusate containing decreased sodium showed no effect on putrescine uptake by isolated rabbit lungs, but there was a significant increase in the uptake of spermidine and spermine. Significant uptake of all three polyamines was also observed when incubated separately with rabbit lung slices for 60 min. HPLC analysis of lung, the perfusate samples, lung slices, and the incubation medium after a 60-min incubation did not indicate the presence of metabolites of these polyamines. Likewise, the analysis of the lung homogenate incubated with polyamines did not show any metabolites confirming the absence of detectable pulmonary metabolism.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

17.
The effects of paraquat (PQ) on lung putrescine, spermidine, and spermine levels, and ornithine decarboxylase (ODC) activity were assessed in rats after 7 days of iv infusion of the herbicide via osmotic minipump. Paraquat administration at a rate of 250 nmol/hr [673 +/- 40 nmol/kg/hr (n = 15)] had no effect on these parameters. In contrast, significant (p less than 0.05) elevations in lung putrescine (407% of control), spermidine (202% of control), and ODC activity (174% of control were measured in lungs of rats given 500 nmol PQ/hr [1.31 +/- 0.53 mumol/kg/hr (n = 14)]. Since evidence of lung damage was, likewise, observed only in the high-dose PQ rats, these changes in polyamine metabolism could have been a nonspecific response to PQ-induced lung injury rather than a direct biochemical effect of PQ. The results suggest that stimulation of polyamine biosynthesis may play an important role in PQ-induced lung injury. This role may involve regulation of repair mechanisms or, conversely, the polyamines may actually mediate PQ-induced fibrotic changes in the lung.  相似文献   

18.
Polyamines (putrescine, spermidine and spermine) are aliphatic amines that are produced by the action of ornithine decarboxylase (ODC) in a rate-limiting and protein kinase C (PKC)-regulated step. Because high levels of polyamines are found in the synovial fluid of arthritic patients, the aim of the present study was to identify the role of peripherally produced polyamines in a model of inflammatory pain induced by adjuvant. The subcutaneous injection of Complete Freund's adjuvant (CFA, 50 μL/paw) caused the development of mechanical allodynia and edema. Moreover, it increased ODC expression and activity and PKC activation. Administration of the selective ODC inhibitor DFMO (10 μmol/paw) attenuated the development of allodynia and edema and decreased ODC activity in both control and CFA-treated animals. Furthermore, administration of the PKC inhibitor GF109203X (1 nmol/paw) reduced allodynia and ODC activity in animals injected with CFA. A subcutaneous injection of putrescine (10 μmol/paw), spermidine (3–10 μmol/paw) or spermine (0.3–3 μmol/paw) into the rat paw also caused mechanical allodynia and edema. The present results suggest that endogenously synthesized polyamines are involved in the development of nociception and edema caused by an adjuvant. Moreover, polyamine production in inflammatory sites seems to be related to an increase in ODC activity stimulated by PKC activation. Thus, controlling polyamine synthesis and action could be a method of controlling inflammatory pain.  相似文献   

19.
In the present investigation, the effects of polyamines, spermidine and spermine on events mediated by the N-methyl-D-aspartate (NMDA) receptor complex were examined. Spermine and spermidine did not alter basal levels of cyclic GMP (cGMP) in the cerebellum of the mouse, over a wide range of concentrations. However, exogenously added spermine, spermidine, D- and L-ornithine and putrescine attenuated the increases in cGMP seen after the administration of D-serine, an agonist of the NMDA receptor-associated glycine recognition sites. Spermine and/or spermidine also antagonized harmaline-, methamphetamine- and pentylenetetrazol-induced increases in the levels of cGMP. Spermidine also potentiated (+)-MK-801 (dizocilipine)-induced attenuation of basal levels of cGMP. Intracerebroventricular administration of ifenprodil, a suggested polyamine antagonist, did not antagonize spermine- and spermidine-induced attenuation of the response to D-serine. These data suggest that exogenously added polyamines attenuate events mediated by the NMDA receptor complex, in an ifenprodil-insensitive manner.  相似文献   

20.
It was found that 1 mM 2,4-dichlorophenoxyacetate (2,4-D) inhibited DNA and protein synthesis in Chinese hamster ovary (CHO) cells. When the possible relationship of this phenomenon to the presence of polyamines in the culture medium was investigated, it was found that: (a) the pesticide inhibited ornithine decarboxylase activity; (b) when the concentration of polyamines present in cells treated with the pesticide was determined, the putrescine concentration did not change, and the spermine and spermidine concentration decreased; (c) the addition of spermidine and spermine to CHO cells grown in the presence of 2,4-D normalized DNA and protein synthesis. Putrescine did not have any effect.  相似文献   

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