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Effect of the polyamine oxidase inactivator MDL 72527 on N(1)-(n-octanesulfonyl)spermine toxicity.

N(1)-(n-octanesulfonyl)spermine (N(1)OSSpm) is a potent calmodulin antagonist. In the present work, its toxicity to DHD/K12/TRb and CaCo-2 cells, two colon carcinoma-derived cell lines, was studied with the aim to identify those properties of the cells, which determine their sensitivity to N(1)OSSpm and related structures. Exposure of the cells to MDL 72527, a compound considered to be a selective inactivator of polyamine oxidase (PAO) increased the cytotoxicity of N(1)OSSpm to both cell lines. In contrast, toxicity of trifluoperazine, a calmodulin antagonist with a polyamine-unrelated structu

Acceleration of purine degradation by periodontal diseases.

Periodontal diseases, such as gingivitis and periodontitis, are characterized by bacterial plaque accumulation around the gingival crevice and the subsequent inflammation and destruction of host tissues. To test the hypothesis that cellular metabolism is altered as a result of host-bacteria interaction, we performed an unbiased metabolomic profiling of gingival crevicular fluid (GCF) collected from healthy, gingivitis, and periodontitis sites in humans, by liquid and gas chromatography mass spectrometry. The purine degradation pathway, a major biochemical source for reactive oxygen species (RO

Biochemical, structural, and transglutaminase substrate properties of human loricrin, the major epidermal cornified cell envelope protein.

Loricrin is the major protein of the cornified cell envelope of terminally differentiated epidermal keratinocytes which functions as a physical barrier. In order to understand its properties and role in cornified cell envelope, we have expressed human loricrin from a full-length cDNA clone in bacteria and purified it to homogeneity. We have also isolated loricrin from newborn mouse epidermis. By circular dichroism and fluorescence spectroscopy, the in vivo mouse and bacterially expressed human loricrins possess no alpha or beta structure but have some organized structure in solution associated

Molecular patterns of clinically important fluoroquinolone resistance in multidrug-resistant Klebsiella pneumoniae isolates during nosocomial outbreaks in Shanghai, PR China.

Introduction. The soaring resistance of Klebsiella pneumoniae to fluoroquinolones in PR China has substantially limited the application of t … one or in combination, co-occurring with genes (bla) encoding β-lactamases, 16S rRNA methylases and putrescine ABC permeases. AcrR, an AcrAB transcriptional repressor, was insertion-inactivated by the IS5-like element in ST11 isolates. The encoding sequences of OmpK35 and OmpK36 genes were associated with specific STs and wzi alleles. ST11, ST15-wzi19 and ST …

The role of polyamine metabolism in remodeling immune responses and blocking therapy within the tumor immune microenvironment.

The study of metabolism provides important information for understanding the biological basis of cancer cells and the defects of cancer treatment. Disorders of polyamine metabolism is a common metabolic change in cancer. With the deepening of understanding of polyamine metabolism, including molecular functions and changes in cancer, polyamine metabolism as a new anti-cancer strategy has become the focus of attention. There are many kinds of polyamine biosynthesis inhibitors and transport inhibitors, but not many drugs have been put into clinical application. Recent evidence shows that polyamin

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… Meanwhile, putrescine derived from macrophages induces 5-FU resistance in colorectal cancer ( 113 ). … It was also observed that increased arginine in M(IL-4) promoted putrescine production by ODC and increased flux of putrescine to spermidine, which could be used to synthesize hypusine. …

Chemosynthetic alphaproteobacterial diazotrophs reside in deep-sea cold-seep bottom waters.

UNLABELLED: Nitrogen (N)-fixing organisms, also known as diazotrophs, play a crucial role in N-limited ecosystems by controlling the product … rved abundant transcripts mapped to genes involved in the transport systems for acetate, spermidine/putrescine, and pectin oligomers, suggesting that Seep-BW-D1 can utilize organics from the intermediates synthesized by methane-oxidizing microorganisms, decaying tissues from cold-seep benthic animals, and refractory pectin derived from upper photosynthetic e …

Gene overexpression reduces inhibitory metabolites to enhance CHO cell growth and IgG1 production.

Controlling the generation of toxic by-products in mammalian bioprocess to maximize therapeutic protein production and glycosylation patterns is a challenge. Intracellular metabolism is often not well-regulated and known to secrete toxic intermediate by-products which hampers cellular performance and negatively impacts critical quality attributes (CQA) of cells. Previous studies have identified trigonelline (TRI), n-acetyl putrescine (NAP), aconitic acid (AA), and cytidine monophosphate (CMP) generated through CHO cell metabolism and verified their negative impacts on growth and antibody produ…

The c-myc gene regulates the polyamine pathway in DMSO-induced apoptosis.

It is accepted that apoptosis is a gene-controlled process of cellular self-destruction. It occurs during physiological regulation and in pathological situations in the life of a cell. In the immune system, several different intracellular and extracellular factors have been associated with the induction of apoptosis, and the final responses depend on the cell system and the acquired signals. In lymphoid cells, dexamethasone-induced apoptosis is associated with c-myc downregulation in cells that remain in G0-G1 until the point of death. Ornithine decarboxylase (ODC), a key enzyme involved in po

Spermine deficiency in Gy mice caused by deletion of the spermine synthase gene.

Two mouse mutations gyro (Gy) and hypophosphatemia (Hyp) are mouse models for X-linked hypophosphatemic rickets and have been shown to be deleted for the 5' and 3' end of the mouse homolog of PHEX (phosphate regulating gene with homologies to endopeptidases on the X chromosome; formerly called PEX), respectively. In addition to the metabolic disorder observed in Hyp mice, male Gy mice are sterile and show circling behavior and reduced viability. The human SMS (spermine synthase) gene maps approximately 39 kb upstream of PHEX and is transcribed in the same direction. To elucidate the complex ph

Sequence, expression and functional analysis of the Coccidioides immitis ODC (ornithine decarboxylase) gene.

The ornithine decarboxylase (ODC) gene of the human respiratory fungal pathogen, Coccidioides immitis (Ci) was cloned, sequenced, chromosome-mapped, and expressed in Escherichia coli (Ec). The genomic, cDNA and translated sequences are presented. Transformation of an ODC null mutant strain of Ec (EWH 319) with the Ci ODC gene was conducted to confirm function of the protein encoded by the fungal gene. Activity of the enzyme by the bacterial transformant was inhibited by 1, 4-diamino-2-butanone (DAB), a known inhibitor of eukaryotic ODC. Temporal expression of the Ci ODC gene during the parasit

A Preliminary Report of the Biochemical and Clinical Effects of 1,4-Diaminobutane on Prevention of Human Hypertrophic Scars.

Objective evidence for the role of inhibition of collagen cross-linking in human scar using a nontoxic topical inhibitor, 1,4-diaminobutane (1,4 DAB), in patients with scars at risk for hypertrophic scar formation is presented. The authors used a concentration of 1,4 DAB of 0.8% (weight/volume) in a cream base similar to Glaxal Base. Application was once per day at night. The control was treated with cream base alone. In treatment phase studies at 2 months, tissue biopsies were performed and used to determine a therapeutic effect biochemically in paired scars harvested chosen with typical hype

Clinical utility of a novel colorimetric chair side test for oral malodour.

AIM: The aim of this study was to evaluate the utility of a simple colorimetric chair side test detecting amines in saliva as an adjunct test in the oral malodour diagnosis. MATERIAL AND METHODS: Non-stimulated saliva samples were collected from 100 volunteers with different degrees of oral malodour. The amount of amines detected by the test was estimated clinically (colorimetric test), confirmed semi quantitatively in the laboratory (standard addition method) and consequently compared with (i) the organoleptic score (OLS); (ii) the volatile sulphur compounds (VSCs) levels (OralChroma(™)) and

Longitudinal characterization of the metabolome of dairy cows transitioning from one lactation to the next: Investigations in fecal samples.

The fecal metabolome comprises metabolites that are excreted or not absorbed by the animal. This study examined the changes in the fecal met … protein metabolism for milk production. Higher concentrations of polyamines, such as spermidine and putrescine, were observed postpartum, indicating increased cell growth and improved tissue regeneration. Elevated gamma-aminobutyric acid levels during lactation indicate increased microbial activity driven by a nutrient-rich diet. Results showed significant a …

Urinary Microbiome Dysbiosis in Children With Congenital Uropathies at Varying Risk for Urinary Tract Infections.

INTRODUCTION: Febrile urinary tract infections (UTIs) may occur in 30% to 50% of children with vesicoureteral reflux (VUR) or posterior uret … nd branched-chain fatty acid and spermidine production; high-risk microbiomes overproduced ammonia, putrescine, and cadaverine. Resistance to 18 of 22 routinely tested antibiotics was almost confined to the 31 risk-associated microbiomes (P = 0.001). During the median (interquartile range) follow-up of 564 (518-594) months, 14 of 36 children with CAKUT devel …

Metabolic modeling of single Th17 cells reveals regulators of autoimmunity.

Metabolism is a major regulator of immune cell function, but it remains difficult to study the metabolic status of individual cells. Here, we present Compass, an algorithm to characterize cellular metabolic states based on single-cell RNA sequencing and flux balance analysis. We applied Compass to associate metabolic states with T helper 17 (Th17) functional variability (pathogenic potential) and recovered a metabolic switch between glycolysis and fatty acid oxidation, akin to known Th17/regulatory T cell (Treg) differences, which we validated by metabolic assays. Compass also predicted that T

Role of polyamine metabolism in kainic acid excitotoxicity in organotypic hippocampal slice cultures.

Polyamines are ubiquitous cations that are essential for cell growth, regeneration and differentiation. Increases in polyamine metabolism have been implicated in several neuropathological conditions, including excitotoxicity. However, the precise role of polyamines in neuronal degeneration is still unclear. To investigate mechanisms by which polyamines could contribute to excitotoxic neuronal death, the present study examined the role of the polyamine interconversion pathway in kainic acid (KA) neurotoxicity using organotypic hippocampal slice cultures. Treatment of cultures with N1,N(2)-bis(2

Beta-adrenergic stimulation and cAMP mobilize Ca2+ from an IP3-insensitive pool in rat submandibular granular ducts.

The beta-adrenergic agonist isoproterenol induced an increase in intracellular calcium concentration ([Ca2+]i) in rat submandibular granular ducts that was blocked by beta-adrenergic but not by alpha-adrenergic or muscarinic antagonists. This effect was only partially inhibited by the selective beta 1- and beta 2-adrenergic antagonists atenolol and ICI-118,551, but was completely blocked by the combination of the two, suggesting the involvement of multiple (or atypical) beta-adrenergic receptor subtypes. The response to isoproterenol was mimicked by forskolin, 3-isobutyl-1-methylxanthine, and

Myeloid Cell-Derived Arginase in Cancer Immune Response.

Amino acid metabolism is a critical regulator of the immune response, and its modulating becomes a promising approach in various forms of immunotherapy. Insufficient concentrations of essential amino acids restrict T-cells activation and proliferation. However, only arginases, that degrade L-arginine, as well as enzymes that hydrolyze L-tryptophan are substantially increased in cancer. Two arginase isoforms, ARG1 and ARG2, have been found to be present in tumors and their increased activity usually correlates with more advanced disease and worse clinical prognosis. Nearly all types of myeloid

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… Polyamines, such as putrescine, spermine, or spermidine are necessary for cell proliferation, while proline is necessary for collagen synthesis. Initially, it was thought that arginase is expressed only in the liver. … Once entering the cell, L-arg turned out to be rapidly converted into L-ornithine, agmatine, and putrescine. …

[Arginase activity in plasma and erythrocytes in children with hematologic diseases].

INTRODUCTION: Arginase (EC 3.5.3.1) is one of the essential enzymes in the terminal stages of the urea cycle in the liver which participates in the elimination of ammonia from the human body [1, 7]. Except in liver tissue arginase is also present in many human tissues and in the circulating blood cells, especially in erythrocytes and leukocytes. Arginase splits arginase to urea and ornithine that serve for biosynthesis of amino acid proline, glutamic acid and biosynthesis of polyamines-spermine, spermidine and putrescine. Arginase activity is high during the mitotic cycle, with the function in…

Blockade by ifenprodil of high voltage-activated Ca2+ channels in rat and mouse cultured hippocampal pyramidal neurones: comparison with N-methyl-D-aspartate receptor antagonist actions.

1. The block by ifenprodil of voltage-activated Ca2+ channels was investigated in intracellular free calcium concentration ([Ca2+]i) evoked … dil 20 micro M on high-[K+]0-evoked rises in [Ca2+]. were attenuated by spermine 0.25 mM but not by putrescine 1 or 5 mM. In contrast,spermine 0.1 mM increased rises in [Ca2+]i evoked by NMDA and enhanced the ifenprodil (5 micro M) block of NMDA-evoked rises in [Ca2+]i.4. Similar results were obtained in mouse cultured hippocampal pyramidal neurones under wh …