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1.
Human amniotic membrane (hAM) has recently drawn attention as an upcoming anti-cancer therapy. Regarding the strategies which have already investigated, little is known about hAM protein extracts (hAMPE) effect on cancer. So, this work aims to study the effect of hAMPE in metabolic activity of several human cancer cell lines. hAMPE were mechanically obtained, thus avoiding the effect of detergents and other reagents commonly used in protein extraction under the cell lines studied. After quantification of proteins in hAMPE, their effect on the metabolic activity of 21 human cancer cell lines was assessed by 3-(4,5-dimethylthia-zolyl-2)2,5-diphenyltetrazolium bromide (MTT) assay. Our results indicate that there is an inhibition of metabolic activity until 25 and 50 % in two and seven cell lines, respectively. Five cell lines proved to be very sensitive to hAMPE, being its metabolic activity more than 50 % inhibited. Our results show that hAMPE can inhibit the metabolic activity of some human cancer cell lines. However, research about this cell line-dependent response to hAMPE becomes indispensable.  相似文献   

2.
Changes in the functional activity of the synthesis apparatus of rat blood lymphocytes under different scheme in application of bioadditive Soma after acute X-irradiation by fluorescent microspectrometry. Some metabolic indices in animals were investigated too. It has been shown the bioadditive Soma using in norm reliably increased the synthetic activity on days 13 and 20. Preliminary Soma using during a month followed by the same interval increased the animal radioresistance (scheme 1), while the Soma using immediately after irradiation (scheme 2) revealed no pronounced radioprotective effect. It was found the Soma increased metabolism that may be important to recover homeostasis. The results show the expediency of further investigation of the Soma radioprotective properties with different concentrations and schemes as well as the necessity of monitoring the immune system during Soma using.  相似文献   

3.
Some aspects of peroxisome proliferator activated receptors (PPAR) involvement in regulation of stress-dependent biological processes leading to insulin resistance, lipid imbalance, hypertension and inflammation are reviewed. Analysis of literature data clearly shows the main role of PPAR in stress signal transduction following to metabolic disbalance development under prolonged stress conditions. The interplay of three PPAR isoforms functional activity with metabolic process disturbances during stress is under special emphasis. Taking into account experimental data described in literature we suggest that PPAR activation under acute stress is an adaptive response while stable PPAR hyperexpression under prolonged stress can cause insulin resistance, hypertension, and visceral obesity. The strategy of PPAR using as pharmacological targets in metabolic syndrome correction is under consideration.  相似文献   

4.
Obesity is increasing in industrialized countries at an alarming rate. Recent studies have linked this condition with changes in the circadian regulation, and circadian clock dysfunctions have also been linked to metabolic disorders. When in captivity and fed a regular rodent chow diet ad libitum some volcano mice, Neotomodon alstoni (endemic species of Mexico) become overweight and display symptoms equivalent to metabolic syndrome. The aim of this work was to observe whether there are significant changes in the functional properties of the circadian system, namely in the entraining circadian locomotor activity rhythm, between mice that became obese and normal adult mice. Freely moving circadian rhythms of locomotor activity were tested under constant conditions as well as under conditions of discrete and continuous entrainment. Our results show that volcano lean mice present a phase response curve with larger delays than advances, indicating that re-entrainment is more easily achieved by delays. Volcano obese mice are less efficient at re-entraining because they show smaller phase shifts in delays than control mice. These results indicate that obesity in N. alstoni has a negative effect on the circadian mechanisms that integrate the photic entrainment.  相似文献   

5.
The studies showed that mytilan, a polysaccharide from Crenomytilus grayanus had a marked activating effect on macrophages evident from respective morphological changes and increased metabolic and functional activity of the macrophages. Exposure to mytilan resulted in an increase in the number of the macrophages and their size (optic microscopy), changes in their surface (scanning microscopy) and ultrastructural reconstruction of the cells (light microscopy). It was shown that subcutaneous and intraperitoneal administration of mytilan defined a decrease in the activity of 5'-nucleotidase in the macrophages of the peritoneal exudate from ++noninbred mice and mice CBA. Moreover, under the influence of mytilan the macrophage phagocytic activity against E. coli, S. aureus, P. aeruginosa and P. vulgaris increased in vivo and in vitro.  相似文献   

6.

Background

Experimental observations and numerical studies with dissipative metabolic networks have shown that cellular enzymatic activity self-organizes spontaneously leading to the emergence of a metabolic core formed by a set of enzymatic reactions which are always active under all environmental conditions, while the rest of catalytic processes are only intermittently active. The reactions of the metabolic core are essential for biomass formation and to assure optimal metabolic performance. The on-off catalytic reactions and the metabolic core are essential elements of a Systemic Metabolic Structure which seems to be a key feature common to all cellular organisms.

Methodology/Principal Findings

In order to investigate the functional importance of the metabolic core we have studied different catalytic patterns of a dissipative metabolic network under different external conditions. The emerging biochemical data have been analysed using information-based dynamic tools, such as Pearson''s correlation and Transfer Entropy (which measures effective functionality). Our results show that a functional structure of effective connectivity emerges which is dynamical and characterized by significant variations of bio-molecular information flows.

Conclusions/Significance

We have quantified essential aspects of the metabolic core functionality. The always active enzymatic reactions form a hub –with a high degree of effective connectivity- exhibiting a wide range of functional information values being able to act either as a source or as a sink of bio-molecular causal interactions. Likewise, we have found that the metabolic core is an essential part of an emergent functional structure characterized by catalytic modules and metabolic switches which allow critical transitions in enzymatic activity. Both, the metabolic core and the catalytic switches in which also intermittently-active enzymes are involved seem to be fundamental elements in the self-regulation of the Systemic Metabolic Structure.  相似文献   

7.
The dynamics of leukocyte number and functional activity of peripheral blood neutrophils under whole-body exposure of healthy mice to low-intensity extremely-high-frequency electromagnetic radiation (EHF EMR, 42.0 GHz, 0.15 mW/cm2, 20 min daily) was studied. It was shown that the phagocytic activity of peripheral blood neutrophils was suppressed by about 50% (p < 0.01 as compared with the sham-exposed control) in 2-3 h after the single exposure to EHF EMR. The effect persisted for 1 day after the exposure, and then the phagocytic activity of neutrophils returned to the norm within 3 days. A significant modification of the leukocyte blood profile in mice exposed to EHF EMR for 5 days was observed after the cessation of exposures: the number of leukocytes increased by 44% (p < 0.05 as compared with sham-exposed animals), mostly due to an increase in the lymphocyte content. The supposition was made that EHF EMR effects can be mediated via the metabolic systems of arachidonic acid and the stimulation of adenylate cyclase activity, with subsequent increase in the intracellular cAMP level. The results indicated that the whole-body exposure of healthy mice to low-intensity EHF EMR has a profound effect on the indices of nonspecific immunity.  相似文献   

8.
9.
Changes in the specific activity of cytochrome oxidase, monoamine oxidase, acetylcholinesterase and Na,K-ATPase in the light and heavy synaptosomes and mitochondria of neurone bodies fractions in the motor cerebral cortex of rabbits were demonstrated under conditions of light (visual) deprivation. These changes were specific of different metabolic cycles and differed in individual cell ultrastructures. The influence of sensory impulsation on functional neuron activity in different projection regions of the cerebral cortex is discussed.  相似文献   

10.
Intranasal insulin (II) administration is widely used in the last years to treat Alzheimer’s disease and other cognitive disorders. Meanwhile, it is almost not used to treat type 2 diabetes mellitus (DM2), mainly due to insufficiently studied molecular mechanisms of its effect on the hormonal and metabolic status of the organism. The effect of II on activity of the hypothalamic signaling systems playing a key role in central regulation of energy metabolism is also poorly studied. The aim of this work was to study the effect of 5-week II treatment of male rats with the neonatal model of DM2 (0.48 ME/rat) both on the metabolic parameters and functional activity of the hypothalamic signaling systems. II treatment of diabetic rats (DI group) was shown to normalize the blood glucose level and restore glucose tolerance and utilization. In the hypothalamus of the DI group, the regulatory effects of agonists of the type 4 melanocortin receptor (MC4R), type 2 dopamine receptor (D2-DAR) and serotonin 1B receptor (S1BR) on adenylyl cyclase (AC) activity, reduced under DM2, were found to be restored; moreover, the inhibitory effect of S1BR agonists became even stronger as compared to control. In the DI group, the restoration of AC hormonal regulation was associated with a considerable increase in expression of the genes encoding S1BR and MC4R. Besides, the attenuation of the AC-stimulating effect of D2-DAR agonists against the background of decreasing expression of the Drd1 gene was found to promote the enhancement of the negative effect of dopamine on AC activity. II treatment did not have a considerable effect on expression of the genes encoding the insulin receptor and insulin receptor substrate-2, which was slightly reduced in the hypothalamus of diabetic rats. Thus, II treatment of rats with the neonatal model of DM2 partially restores the hypothalamic AC signaling pathways regulated by melanocortin, serotonin and dopamine, demonstrating thereby one of the mechanisms of the positive influence of II on energy metabolism and insulin sensitivity in peripheral tissues.  相似文献   

11.
Glycolysis and pentose phosphate pathway (PPP) in red blood cell (RBC) are modulated by the cell oxygenation state. This metabolic modulation is connected to variations in intracellular nicotinamide adenine dinucleotide phosphate‐reduced form (NADPH) and adenosine triphosphate (ATP) levels as a function of the oxygenation state of the cell, and, consequently, it should have physiologic relevance. In the present study, we analysed the effects of amyloid beta peptide (1–42) (Abeta) on RBC metabolism and its relationship with the activity of protein kinase C (PKC). Our results showed that metabolic response to Abeta depended on the degree of cell oxygenation. In particular, under high O2 pressure, in Abeta‐treated RBC, glucose metabolized through PPP approached that metabolized by RBC under low O2 pressure, differently to that observed in untreated cells. The effect of Abeta on RBC metabolism was paralleled by increase in PKC enzyme activity, but cytosolic Ca2+ concentration does not seem to be involved in this mechanism. Incubation of Abeta‐treated RBC with a specific inhibitor of PKC partially restores PPP flux. A possible rationalization of the different metabolic behaviours shown by RBC following Abeta treatment is proposed. It takes into account the known post‐translational modifications to cytoskeleton proteins induced by PKC. The reduction in PPP flux may lead to a weakened defence system of antioxidant reserve in RBC, becoming a source of reactive species, and, consequently, its typical, structural and functional features are lost. Therefore, oxidative stress may outflow from the RBC and trigger damage events in adjacent cells and tissue, thus contributing to vascular damage. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

12.
AMP-activated kinase (AMPK) is a ubiquitous metabolic sensor that inhibits the cystic fibrosis (CF) transmembrane conductance regulator (CFTR). To determine whether CFTR reciprocally regulates AMPK function in airway epithelia and whether such regulation is involved in lung inflammation, AMPK localization, expression, and activity and cellular metabolic profiles were compared as a function of CFTR status in CF and non-CF primary human bronchial epithelial (HBE) cells. As compared with non-CF HBE cells, CF cells had greater and more diffuse AMPK staining and had greater AMPK activity than their morphologically matched non-CF counterparts. The cellular [AMP]/[ATP] ratio was higher in undifferentiated than in differentiated non-CF cells, which correlated with AMPK activity under these conditions. However, this nucleotide ratio did not predict AMPK activity in differentiating CF cells. Inhibiting channel activity in non-CF cells did not affect AMPK activity or metabolic status, but expressing functional CFTR in CF cells reduced AMPK activity without affecting cellular [AMP]/[ATP]. Therefore, lack of functional CFTR expression and not loss of channel activity in CF cells appears to up-regulate AMPK activity in CF HBE cells, presumably through non-metabolic effects on upstream regulatory pathways. Compared with wild-type CFTR-expressing immortalized CF bronchial epithelial (CFBE) cells, DeltaF508-CFTR-expressing CFBE cells had greater AMPK activity and greater secretion of tumor necrosis factor-alpha and the interleukins IL-6 and IL-8. Further pharmacologic AMPK activation inhibited inflammatory mediator secretion in both wild type- and DeltaF508-expressing cells, suggesting that AMPK activation in CF airway cells is an adaptive response that reduces inflammation. We propose that therapies to activate AMPK in the CF airway may be beneficial in reducing excessive airway inflammation, a major cause of CF morbidity.  相似文献   

13.
Metabolism of arachidonic acid by cytochrome P450 (CYP) to biologically active eicosanoids has been recognized increasingly as an integral mediator in the pathogenesis of cardiovascular and metabolic disease. CYP epoxygenase-derived epoxyeicosatrienoic and dihydroxyeicosatrienoic acids (EET + DHET) and CYP ω-hydroxylase-derived 20-hydroxyeicosatetraenoic acid (20-HETE) exhibit divergent effects in the regulation of vascular tone and inflammation; thus, alterations in the functional balance between these parallel pathways in liver and kidney may contribute to the pathogenesis and progression of metabolic syndrome. However, the impact of metabolic dysfunction on CYP-mediated formation of endogenous eicosanoids has not been well characterized. Therefore, we evaluated CYP epoxygenase (EET + DHET) and ω-hydroxylase (20-HETE) metabolic activity in liver and kidney in apoE(-/-) and wild-type mice fed a high-fat diet, which promoted weight gain and increased plasma insulin levels significantly. Hepatic CYP epoxygenase metabolic activity was significantly suppressed, whereas renal CYP ω-hydroxylase metabolic activity was induced significantly in high-fat diet-fed mice regardless of genotype, resulting in a significantly higher 20-HETE/EET + DHET formation rate ratio in both tissues. Treatment with enalapril, but not metformin or losartan, reversed the suppression of hepatic CYP epoxygenase metabolic activity and induction of renal CYP ω-hydroxylase metabolic activity, thereby restoring the functional balance between the pathways. Collectively, these findings suggest that the kinin-kallikrein system and angiotensin II type 2 receptor are key regulators of hepatic and renal CYP-mediated eicosanoid metabolism in the presence of metabolic syndrome. Future studies delineating the underlying mechanisms and evaluating the therapeutic potential of modulating CYP-derived EETs and 20-HETE in metabolic diseases are warranted.  相似文献   

14.
氮输入对湿地生态系统碳氮循环具有重要影响,研究湿地土壤微生物功能多样性及碳氮组分对氮输入的响应,对于明确湿地土壤碳氮循环微生物驱动机制具有重要意义。依托长期野外氮输入模拟试验,利用Biolog-ECO微平板技术,分析不同浓度氮输入:N1(6 g N m-2 a-1)、N2(12 g N m-2 a-1)和N3(24 g N m-2 a-1)对湿地土壤表层(0-15 cm)和亚表层(15-30 cm)微生物碳源代谢活性、功能多样性和碳氮组分的影响。结果表明:N2处理显著提高了亚表层土壤微生物碳源代谢活性和McIntosh指数,N3处理显著降低了表层土壤微生物Shannon指数和Shannon-evenness指数。随氮输入浓度增加湿地表层土壤微生物对糖类的利用率显著降低,N3处理表层土壤微生物对胺类的利用率以及亚表层土壤微生物对醇类的利用率显著提高。N1处理显著提高了湿地表层土壤全氮和微生物量碳含量;N2、N3处理显著提高了土壤铵态氮、硝态氮含量;N3处理显著降低了土壤pH值。湿地土壤pH、总碳、溶解性有机碳含量是影响微生物碳源代谢活性和功能多样性的重要因素,土壤溶解性有机碳、铵态氮、全氮含量、含水率是影响微生物碳源利用变化的主要因子。  相似文献   

15.
Our previous results have shown that metabolic and thermal stressors influence interscapular brown adipose tissue (IBAT) metabolic activity by increasing oxygen consumption and, consequently, altering the toxic reactive oxygen species (ROS) production and the antioxidative system activity. Since there is not enough evidence about the effect of psychosocial stressors on these processes, we studied the effect of acute crowding stress on the IBAT and hypothalamic monoamine oxidase (MAO) activity as well as IBAT antioxidative enzymes, manganese (MnSOD), copper-zinc superoxide dismutase (CuZnSOD) and catalase (CAT), as the relevant indicators of IBAT metabolic alternations under the stress exposure and the returning of animals to control conditions. The results indicated that acute crowding stress did not change the hypothalamic and IBAT MAO activities, the generation of ROS and, consequently, the IBAT CuZnSOD and CAT activities. However, all three antioxidative enzymes were affected only after the recovery period. It seems that peripheral overheating of rats during acute crowding changes the stress nature, by becoming more thermal than psychosocial and by suppression the hypothalamic efferent pathways involved in the IBAT thermogenesis regulation. However, it seems that returning of the animals to the control conditions after the stress termination causes the reactivation of IBAT thermogenesis with tendency to normalise the body temperature.  相似文献   

16.
Changes in functional activity of specific enzyme reactions in the cells of pectinolytic bacteria from the gastrointestinal tract of animals in vitro cultivated in the medium containing pectin or glucose were studied against a background of the low dose effect of the wide spread biocide pentachlorophenol alone as well as in combination with the natural sorbents clinoptilolites. Regardless of the absence of transketolase reaction in the cells of all studied strains, they metabolized highly the above substrates that are dissimilar in chemical structure and produced different products of their degradation. It has been shown that the high metabolic level in the cells is provided by the function of the unique enzymatic reaction catalyzed by 2-keto-3-desoxy-6-phosphogluconate aldolase (EC 4.1.2.14) that permits to use effectively the metabolic pathway of Entner-Doudoroff. Cells could also utilize the same substrates via the Embden-Meyerhof-Parnas pathway, therefore they possess the other key reaction that is catalyzed by fructosobiphosphate aldolase (EC 4.1.2.13). Even a low dose of PCP (20 microM) decreased sharply activity of the mentioned key enzymes and intermediates' production in the cells of the studied strains with the use of both substrates. However, presence of clinoptilolites in the medium reduced significantly the biocide inhibition effect. Furthermore, in the medium with glucose, protection of intracellular metabolism with the help of sorbents was registered more clearly than with pectin. This can evidence for more mobile and simpler possibilities of accelerated production of necessary intermediates from glucose that are capable to induce activation of the key enzymatic reactions in cells utilizing selectively the substrates (which are different in accessibility and other characteristics) under the toxic agent effect.  相似文献   

17.
Hamilton JJ  Reed JL 《PloS one》2012,7(4):e34670
Genome-scale network reconstructions are useful tools for understanding cellular metabolism, and comparisons of such reconstructions can provide insight into metabolic differences between organisms. Recent efforts toward comparing genome-scale models have focused primarily on aligning metabolic networks at the reaction level and then looking at differences and similarities in reaction and gene content. However, these reaction comparison approaches are time-consuming and do not identify the effect network differences have on the functional states of the network. We have developed a bilevel mixed-integer programming approach, CONGA, to identify functional differences between metabolic networks by comparing network reconstructions aligned at the gene level. We first identify orthologous genes across two reconstructions and then use CONGA to identify conditions under which differences in gene content give rise to differences in metabolic capabilities. By seeking genes whose deletion in one or both models disproportionately changes flux through a selected reaction (e.g., growth or by-product secretion) in one model over another, we are able to identify structural metabolic network differences enabling unique metabolic capabilities. Using CONGA, we explore functional differences between two metabolic reconstructions of Escherichia coli and identify a set of reactions responsible for chemical production differences between the two models. We also use this approach to aid in the development of a genome-scale model of Synechococcus sp. PCC 7002. Finally, we propose potential antimicrobial targets in Mycobacterium tuberculosis and Staphylococcus aureus based on differences in their metabolic capabilities. Through these examples, we demonstrate that a gene-centric approach to comparing metabolic networks allows for a rapid comparison of metabolic models at a functional level. Using CONGA, we can identify differences in reaction and gene content which give rise to different functional predictions. Because CONGA provides a general framework, it can be applied to find functional differences across models and biological systems beyond those presented here.  相似文献   

18.
The capacity of the bone marrow-derived myelopeptide-1 (MP-1) to affect in vivo and in vitro the functional activity of phagocytes of intact mice and mice treated with a cytostatic agent (cyclophosphane) has been studied. It was found that MP-1 produces a correcting effect on the functional activity of bone marrow and peripheral blood phagocytes. An optimal scheme of the injection of MP-1 to mice with the cyclophosphane-induced immunodeficiency was developed, which provides a maximum immunocorrecting action. MP-1 had the most pronounced effect on the quantitative characteristics and the functional activity of phagocytes of different localization when introduced prior to the cytostatic; under these conditions, the pep tide affects peripheral blood neutrophils. The results obtained enable one to consider MP-1 as a preparation protecting the peripheral blood phagocytes from the damaging action of cyclophosphane.  相似文献   

19.
20.
We studied the influence of parathyroid hormone (PTH) on the functional activity of white rat and human platelets, and examined in particular possible mechanisms of PTH influence on the platelet aggregation activity. It has been stated that PTH renders a marked dose-dependent proaggregative effect on platelets. Possible mechanisms of proaggregative effect of parathyroid hormone were examined on platelets using substances with defined mechanisms of the effect. Examination of PTH effect on lectin-intermediated aggregation in a suspension of washed platelets shows that metabolic activation of platelets by PTH causes an increased expression on their plasmic membrane mainly of glycoprotein complex IIb-IIIa and in a lesser degree of glycoprotein complexes Ia-IIa and IV which take part in the formation of interplatelet contact.  相似文献   

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