Polyamine Content Research Articles

Polyamines and its analogue modulates amyloid fibrillation in lysozyme: A comparative investigation

BackgroundPolyamines can induce protein aggregation that can be related to the physiology of the cellular function. Polyamines have been implicated in protein aggregation which may lead to neuropathic and non neuropathic amyloidosis. Scope of reviewChange in the level of polyamine concentration has been associated with ageing and neurodegeneration such as Parkinson's disease, Alzheimer's disease. Lysozyme aggregation in the presence of polyamines leads to non neuropathic amyloidosis. Polyamine analogues can suppress or inhibit protein aggregation suggesting their efficacy against amyloidogenic protein aggregates. Major conclusionsIn this study we report the comparative interactions of lysozyme with the polyamine analogue, 1-naphthyl acetyl spermine in comparison with the biogenic polyamines through spectroscopy, calorimetry, imaging and docking techniques. The findings revealed that the affinity of binding varied as spermidine > 1-naphthyl acetyl spermine > spermine. The biogenic polyamines accelerated the rate of fibrillation significantly, whereas the analogue inhibited the rate of fibrillation to a considerable extent. The polyamines bind near the catalytic diad residues viz. Glu35 and Asp52, and in close proximity of Trp62 residue. However, the analogue showed dual nature of interaction where its alkyl amine region bind in same way as the biogenic polyamines bind to the catalytic site, while the naphthyl group makes hydrophobic contacts with Trp62 and Trp63, thereby suggesting its direct influence on fibrillation. General significanceThis study, thus, potentiates, the development of a polyamine analogue that can perform as an effective inhibitor targeted towards aggregation of amyloidogenic proteins.

ATP13A2 deficiency disrupts lysosomal polyamine export.

ATP13A2 (PARK9) is a late endolysosomal transporter that is genetically implicated in a spectrum of neurodegenerative disorders, including Kufor-Rakeb syndrome-a parkinsonism with dementia1-and early-onset Parkinson's disease2. ATP13A2 offers protection against genetic and environmental risk factors of Parkinson's disease, whereas loss of ATP13A2 compromiseslysosomes3. However, the transport function of ATP13A2in lysosomes remains unclear. Here we establish ATP13A2 as a lysosomal polyamine exporter that shows the highest affinity for spermine among the polyamines examined. Polyamines stimulate the activity of purified ATP13A2, whereas ATP13A2 mutants that are implicated in disease are functionally impaired to a degree that correlates with the disease phenotype. ATP13A2 promotes the cellular uptake of polyamines by endocytosis and transports them into the cytosol, highlighting a role for endolysosomes in the uptake of polyamines into cells. At high concentrations polyamines induce cell toxicity, which is exacerbated by ATP13A2 loss due to lysosomal dysfunction, lysosomal rupture and cathepsin B activation. This phenotype is recapitulated in neurons and nematodes with impaired expression of ATP13A2 or its orthologues. We present defective lysosomal polyamine export as a mechanism for lysosome-dependent cell death that may be implicated in neurodegeneration, and shed light on the molecular identity of the mammalian polyamine transport system.

Role of the Arabidopsis calcineurin B-like protein-interacting protein kinase CIPK21 in plant cold stress tolerance

The Arabidopsis calcineurin B-like protein-interacting protein kinase CIPK21 gene (AtCIPK21) plays important roles in cell metabolism, plant development, and abiotic stress responses. However, the function of the AtCIPK21 gene in cold stress tolerance in plant cells is not fully understood. In this study, we use cell cultures of three plant species including rice (Oryza sativa L.), cotton (Gossypium hirsutum L.), and white pine (Pinus strobus L.), as well as Agrobacterium tumefaciens strain GV3101 harboring pBI-AtCIPK21 to generate transgenic cell lines. After confirmation of integration of the AtCIPK21 gene into the genome by polymerase chain reaction (PCR), southern blotting, and northern blotting analyses, the rice, cotton, and pine AtCIPK21 transgenic cell lines were used to examine cold stress tolerance. The experimental results demonstrated that overexpression of the AtCIPK21 gene enhanced cold stress tolerance of transgenic cells by increasing cell viability and cell growth rate, decreasing lipid peroxidation and ion leakage, increasing the content of polyamines, as well as elevating the activity of antioxidative enzymes. In rice cells, AtCIPK21 increases expression of Ca2+-dependent protein kinase (CPK) genes and mitogen-activated protein kinase (MAPK) genes under cold stress. These results indicated that overexpression of the AtCIPK21 gene in plant cells improved cold stress tolerance by elevating polyamines content, antioxidative enzyme activity, and expression of CPK genes and MAPK genes. Overexpression of the AtCIPK21 gene may be a valuable approach for engineering plant cold stress tolerance.

Sex-related differences in urinary immune-related metabolic profiling of alopecia areata patients

Alopecia areata is a well-known autoimmune disease affecting humans. Polyamines are closely associated with proliferation and inflammation, and steroid hormones are involved in immune responses. Additionally,bile acids play roles in immune homeostasis by activating various signaling pathways; however, the roles of these substances and their metabolites in alopecia areata remain unclear. In this study, we aimed to identify differences in metabolite levels in urine samples from patients with alopecia areata and healthy controls. To assess polyamine, androgen, and bile acid concentrations, we performed high-performance liquid chromatography-tandem mass spectrometry. Our results showed that spermine and dehydroepiandrosterone levels differed significantly between male patients and controls, whereas ursodeoxycholic acid levels were significantly higher in female patients with alopecia areata than in controls. Our findings suggested different urinary polyamine, androgen, and bile acid concentrations between alopecia areata patients and normal controls. Additionally, levels of endogenous substances varied according to sex, and this should be considered when developing appropriate treatments and diagnostic techniques. Our findings improve ourunderstanding of polyamine, androgen, and bile acid profiles in patients with alopecia areata and highlight the need to consider sex-related differences.

The intracellular water volume modulates the accumulation of cadmium in Euglena gracilis

In order to describe a relatively novel mechanism associated to heavy metal resistance in Euglena gracilis, the osmotic responses during cadmium accumulation were analyzed. Several physiological/biochemical parameters were assessed in E. gracilis exposed to 50 and 200 μM Cd2+, concentrations well within the range found in polluted soils and aquatic environments. The Cd2+ accumulation attained after only 24 h exposure induced marked increases in both the intracellular water volume and cellular size, which were maintained for several days; these changes correlated with (i) an increased intracellular osmolarity (i.e. osmotic pressure) driven by a generalized increase in the osmo-metabolites (trehalose, phosphate-molecules, amino acids, thiol-molecules, betaines and polyamines) content; and (ii) the triggering of antioxidant defenses (increased GSH/GSSG ratios and GPx, GR and APx activities). In contrast, no changes in intracellular volume, cellular size and antioxidant status were observed under hyperaccumulation of Zn2+. Furthermore, E. gracilis cultured in a hypoosmotic medium promoted greater Cd2+ accumulation and water volume, compared to a hyperosmotic medium. These changes were significantly decreased by the aquaporin inhibitors Hg2+ and pentamidine. The results suggested that the cell responses to Cd2+ and osmotic stress share biochemical mechanisms in this algae-like protist, in which Cd2+ accumulation closely correlates with the intracellular water volume changes in an oxidative stress-mediated process.

Spermidine alleviates cardiac aging by improving mitochondrial biogenesis and function.

Polyamines have been shown to delay cellular and organismal aging and to provide cardiovascular protection in humans. Because age-related cardiovascular dysfunction is often accompanied by impaired mitochondrial biogenesis and function, we explored the ability of spermidine (SPD), a major mammalian polyamine, to attenuate cardiac aging through activation of mitochondrial biogenesis. Cardiac polyamine levels were reduced in aged (24-month-old) rats. Six-week SPD supplementation restored cardiac polyamine content, preserved myocardial ultrastructure, and inhibited mitochondrial dysfunction. Immunoblotting showed that ornithine decarboxylase (ODC) and SPD/spermine N1-acetyltransferase (SSAT) were downregulated and upregulated, respectively, in the myocardium of older rats. These changes were paralleled by age-dependent downregulation of components of the sirtuin-1/peroxisome proliferator-activated receptor gamma coactivator alpha (SIRT1/PGC-1α) signaling pathway, an important regulator of mitochondrial biogenesis. SPD administration increased SIRT1, PGC-1α, nuclear respiratory factors 1 and 2 (NRF1, NRF2), and mitochondrial transcription factor A (TFAM) expression; decreased ROS production; and improved OXPHOS performance in senescent (H2O2-treated) cardiomyocytes. Inhibition of polyamine biosynthesis or SIRT1 activity abolished these effects. PGC-1α knockdown experiments confirmed that SPD activated mitochondrial biogenesis through SIRT1-mediated deacetylation of PGC-1α. These data provide new insight into the antiaging effects of SPD, and suggest potential applicability to protect against deterioration of cardiac function with aging.

Physiological performance of Garcinia gardneriana (Planch. & Triana) Zappi: a species with recalcitrant and dormant seeds

Abstract: Garcinia gardneriana (Planch. & Triana) Zappi is a native species widely distributed in Brazil. It has ornamental features, edible fruits, and its leaves have medicinal properties; however, its potential has not been explored. The aim of this study was to evaluate seed physiological performance due to dormancy, desiccation and storage tolerance. Only decoated seeds germinated. Seeds had an initial water content of 1.07 g H2O.g-1 dw and final germination of 95%. Both desiccation to 0.67 g H2O.g-1 dw and storage at 25 ºC for ninety days resulted in decreased germination, 43 and 41%, respectively. Desiccation below 0.25 g H2O.g-1 dw and storage for ninety days at 5 ºC were lethal. A rapid decrease in enzymic protection by superoxide dismutase and ascorbate peroxidase was correlated to desiccation sensitivity. Total polyamines content was higher in fresh seeds and markedly decreased with desiccation. The decrease in enzyme activity and polyamines content seems to be associated with seed viability loss. In sum, G. gardneriana seeds have a low tolerance to desiccation and are sensitive to chilling. Therefore, the seeds can be categorized as recalcitrant and dormant, a rare combination in terms of seed biology.

Effect of N-acetyl-L-cysteine (NAC) on soluble sugar and polyamine content in wheat seedlings exposed to heavy metal stress (Cd, Hg and Pb)

Heavy metal stress adversely affects plant growth and productivity worldwide. Alleviating the stress effect through the exogenous use of various chemical substances has become an interesting area of study in the field of plant stress tolerance. As a thiol compound, the cysteine derivative N-acetylcysteine (N-acetyl- L-cysteine, NAC) is the precursor of glutathione synthesis and a potent ROS scavenger with powerful antioxidant and free radical scavenging capabilities. This study investigated the effects of heavy metals (Cd, Hg and Pb, 100 ?M) on accumulation of soluble sugars and polyamine content in roots and shoots of wheat seedlings, the water potential and proline content in shoots and the role of NAC in protection against heavy metal toxicity. The addition of 1 mM NAC significantly increased root content of glucose, fructose and sucrose in varying degrees (avg. 1.34-, 1.20- and 1.51-fold, respectively) in comparison with heavy metals alone. The treatments led to a significant reduction of sugar content in shoots. Water potential values were highly correlated with proline and sugar content in wheat seedling shoots. Heavy metal stress significantly reduced polyamine content in both plant parts. The addition of NAC increased polyamine content in seedlings in comparison with heavy metals alone in both roots and shoots. These results suggest that NAC may protect plants from oxidative stress damage in heavy metal stress, and this enhancement of stress tolerance seems to involve soluble sugar and polyamine biosynthesis.

Nitrogen metabolism and secondary metabolism regulation of Atropa belladonna by exogenous NO under NaCl stress

Atropa belladonna seedlings were used as experimental materials and cultivated by soil culture method. Different concentrations(0,0.05,0.1,0.2,0.5 mmol·L~(-1))of NO donor sodium nitroprusside(SNP) were sprayed on the leaves. The effects of different concentrations of SNP and different treatment time(4,8,12,16 d) on nitrogen metabolism, secondary metabolite content, precursor content of tropane alkaloid synthesis pathway and expression of key enzyme genes under 100 mmol·L~(-1) NaCl stress were studied. The results showed that with the prolongation of salt stress, the nitrogen metabolism and the accumulation of secondary metabolites of A. belladonna were inhibited to some extent. After treatment with different concentrations of exogenous SNP, the ammonium nitrogen content decreased dramatically, and the contents of nitrate nitrogen, free amino acid, soluble protein and the activities of key enzymes of nitrogen metabolism(NR, GS, GDH) were all greatly improved; the contents of precursor amino acids(ornithine, arginine) and polyamines(Put, Spd, Spm) in the secondary metabolic pathway have increased to varying degrees. The qRT-PCR analysis showed that exogenous SNP treatment can effectively promote the high expression of key enzyme genes PMT, TRⅠ and H6H in the secondary metabolic pathway of A. belladonna, and the production of hyoscyamine and scopolamine were increased notably. In summary, the application of appropriate concentration of SNP can effectively alleviate the inhibition of salt stress on the nitrogen metabolism and secondary metabolism of Atropa belladonna, and enhance its salt tolerance. Overall, 0.1 mmol·L~(-1) and 0.2 mmol·L~(-1) SNP treatment achieved the most remarkable effect.

Chitosan-induced phenolics production is mediated by nitrogenous regulatory molecules: NO and PAs in Linum album hairy roots

Due to medicinal value, phenolics are of great interest. Many investigations have already been conducted on Linum album Kotschy ex Boiss to increase these valuable compounds especially lignans. In the present work, the hairy roots of the L. album were treated with 200 mg L−1 chitosan for 12, 24, 48, and 72 h and the lignan contents were determined by high performance liquid chromatography (HPLC). To understand the governing upstream routes, the contents of hydrogen peroxide (H2O2), nitric oxide (NO), salicylic acid (SA), the activity of antioxidant enzymes, the amino acids, polyamines, and phenylpropanoids were determined by HPLC and spectroscopy techniques. The levels of regulatory molecules (H2O2, NO, and SA) enhanced at first hours of treatment and the antioxidant enzymatic activities increased in correlation with them. This observation might be attributed to adjustment of the oxidative status and direction of the elicited cells toward specific defensive responses. The content of amino acids, polyamines, and phenylpropanoids underwent a time-dependent reprogramming. The amino acid metabolism shifted toward the elevated levels of glutamate, aspartate, arginine, methionine, phenylalanine, and tyrosine after 24 h as well as correlated with the modulation of polyamines and phenylpropanoids. After 72 h, there was a channeling of the cell metabolism towards the accumulation of secondary metabolites, mainly podophyllotoxin, 6-methoxy podophyllotoxin, catechin, and vitexin. These results propose the complex relationship between the regulatory molecules and the profile of nitrogenous compounds enhanced the phenolics accumulation. Chitosan treatment of Linum album hairy roots activates signaling network accompanied by modulation of nitrogenous compounds and alteration of defensive pathways towards production of phenylpropanoids.

РОЛЬ ПОЛИАМИНОВ В ОГРАНИЧЕНИИ ПРОНИЦАЕМОСТИ ВНЕШНЕЙ МЕМБРАНЫ ESCHERICHIA COLI ДЛЯ АНТИБИОТИКОВ

Various hydrophilic antibiotics enter the cells of gram-negative bacteria through porin channels, which can be blocked by polyamine cadaverine. In this paper, we studied the rate of porin-mediated transport and the intracellular concentration of the main biogenic polyamines of Escherichia coli cells subjected to fluoroquinolone antibiotics depending on the exposure time. Porin permeability sharply decreased in the first two hours of antibiotic exposure, after that the transport rate continued to decline, but at a lower rate. Free polyamines accumulated by the second hour of the exposure, then putrescine and spermidine de-clined, and the concentration of cadaverine continued to grow. Activation of micF gene, a product of which is involved in the negative control of ompF porin gene expression, was observed after the two hours of antibiotic exposure. It could be supposed that the inhibition of porin-mediated transport of anti-biotics by blocking pores precedes the mechanisms regulating the number of porins. The paper discusses the probable specialization of polyamines in the regulation of porin-mediated transport of antibiotics.

Strawberry physiological and biochemical responses to chilling and freezing stress and application of alleviating factors as countermeasures

BACKGROUND: Strawberry is usually cultivated in unheated glasshouses or outdoors, suffering many times by low temperatures during the winter period, with the danger of plant losses. OBJECTIVE: To investigate the efficacy of various alleviating agents against chilling and freezing stress. METHODS: Strawberry plants were foliarly treated with various alleviating substances, i.e. glycine betaine, trehalose, salicylic acid and proline and exposed to 5 °C (chilling treatment) for three weeks followed by a three hour exposure to – 10 °C (freezing treatment), while control plants were growing under 20 °C. At the end of each period polyamine and carbohydrate concentration, antioxidant enzymes activities, total phenols and proline concentration, chlorophyll concentration, lipid peroxidation, electrolyte leakage and H2O2 production in the leaves were measured. RESULTS: All applied products alleviated chilling stress, inducing lower electrolyte leakage, but higher sucrose and fructose concentration in the leaves compared to control. Under freezing temperature, salicylic acid proved to be the most efficient based on the lowest leaf damage observed, followed by trehalose and proline. CONCLUSIONS: Salicylic acid was the best alleviation agent based on leaf damage evaluation, by inducing low chlorophyll a degradation, low superoxide dismoutase, peroxidase and polyphenol oxidase activities as well as low putrescine concentration.

Effect of Spermine and Putrescine on Germination and Growth of Vigna Radiate (L.) R. Wilczek Seeds

Polyamines are polycationic hydrocarbons that is found in all plant parts that regulates growth and development. In current study, seeds treated with polyamines,Spermine and Putrescine were studied to evaluate the growth and development in terms of various physiological and biochemical parameters. For this study, seeds were soaked in different strengths of Spermine and Putrescine (0.01mM, 0.1mM and 1mM) for 48 hours and distilled water was used as control. After sprouting, seeds were transferred into half strength M.S. medium and evaluated at every 48 hours for 10 days. Highest seed germination (95%) was obtained in control after 24 hours and it was observed that germination was less in higher concentrations of polyamines. Out of all treatments, 0.01mM concentration showed maximum concentration compared to 0.1mM and 1mM polyamine concentration. First leaves were observed in Putrescine and Spermine treated seeds after 24 hours whereas, first leaves in distilled water treated seeds were observed after 30 hours. Statistical analysis using One Way ANOVA and Dunn’s Post hoc analysis were performed to check the relationship between protein concentration, shoot length, chlorophyll a and b content. It was observed that there is a significant relationship between total protein content and chlorophyll a and b content and also between shoot length and chlorophyll a and b content.However, no significant relationship was observed between shoot length and protein concentration. An attempt has been made to characterize protein profile using SDS-PAGE, however no distinct band was found in treated seeds compared to control.

Differences of endogenous polyamines and putative genes associated with paraquat resistance in goosegrass (Eleusine indica L.).

BackgroundParaquat is one of the most effective herbicides used to control weeds in agricultural management, while the pernicious weed goosegrass (Eleusine indica) has evolved resistance to herbicides, including paraquat. Polyamines provide high-level paraquat resistance in many plants. In the present study, we selected three polyamines, namely, putrescine, spermidine, and spermine, as putative genes to investigate their correlation with paraquat resistance by using paraquat-resistant (R) and paraquat-susceptible (S) goosegrass populations.ResultsThere was no significant difference in the putrescine nor spermine content between the R and S biotypes. However, 30 and 90 min after paraquat treatment, the spermidine concentration was 346.14-fold and 421.04-fold (P < 0.001) higher in the R biotype than in the S biotype, but the spermidine concentration was drastically reduced to a marginal level after 90 min. Since the transcript level of PqE was low while the spermidine concentration showed a transient increase, the PqE gene was likely involved in the synthesis of the paraquat resistance mechanism, regulation of polyamine content, and synthesis of spermidine and spermine. PqTS1, PqTS2, and PqTS3 encode transporter proteins involved in the regulation of paraquat concentration but showed different transcription patterns with synchronous changes in polyamine content.ConclusionEndogenous polyamines (especially spermidine) play a vital role in paraquat resistance in goosegrass. PqE, PqTS1, PqTS2, and PqTS3 were speculated on the relationship between polyamine metabolism and paraquat resistance. To validate the roles of PqE, PqTS1, PqTS2, and PqTS3 in polyamine transport systems, further research is needed.

Effects of high N2/CO2 in package treatment on polyamine-derived 4-Aminobutyrate (GABA) biosynthesis in cold-stored white mushrooms (Agaricus bisporus)

Abstract White mushrooms were harvested and then packaged, the air was evacuated from the package, and then one of two inert gases, N2 or CO2, was pumped into the sealed packages. After storing all mushrooms at 4 °C, dynamic quantitative changes in polyamines and amino acids were subsequently detected. The results showed that the content of polyamines (PAs) in the white mushrooms was significantly increased due to the climacteric effect after 24 h of cold storage, but anaerobic treatment inhibited the biosynthesis of PAs and maintained a level as low as that of fresh mushrooms. In addition, anaerobic treatment significantly changed the amino acid content, especially the content of γ-aminobutyric acid (GABA), which was more markedly increased when the mushrooms were treated with N2. Then, the multiple enzymatic activities related to the GABA synthesis pathway were determined, including that of arginine decarboxylase (ADC), ornithine decarboxylase (ODC), diamine oxidase (DAO), polyamine oxidase (PAO), and glutamate decarboxylation (GAD), and the results showed that PAs metabolism played a great role in driving GABA biosynthesis in mushrooms that were exposed to N2.

Inhibitors of tri- and tetra- polyamine oxidation, but not diamine oxidation, impair the initial stages of wound-induced suberization

The mechanisms regulating, and modulating potato wound-healing processes are of great importance in reducing tuber infections, reducing shrinkage and maintaining quality and nutritional value for growers and consumers. Wound-induced changes in tuber polyamine metabolism have been linked to the modulation of wound healing (WH) and in possibly providing the crucial amount of H2O2 required for suberization processes. In this investigation we determined the effect of inhibition of specific steps within the pathway of polyamine metabolism on polyamine content and the initial accumulation of suberin polyphenolics (SPP) during WH. The accumulation of SPP represents a critical part of the beginning or inchoate phase of tuber WH during closing-layer formation because it serves as a barrier to bacterial infection and is a requisite for the accumulation of suberin polyaliphatics which provide the barrier to fungal infection. Results showed that the inhibitor treatments that caused changes in polyamine content generally did not influence wound-induced accumulation of SPP. Such lack of correlation was found for inhibitors involved in metabolism and oxidation of putrescine (arginine decarboxylase, ornithine decarboxylase, and diamine oxidase). However, accumulation of SPP was dramatically reduced by treatment with guazatine, a potent inhibitor of polyamine oxidase (PAO), and methylglyoxal-bis(guanylhydrazone), a putative inhibitor of S-adenosylmethione decarboxylase which may also cross-react to inhibit PAO. The mode of action of these inhibitors is presumed to be blockage of essential H2O2 production within the WH cell wall. These results are of great importance in understanding the mechanisms modulating WH and ultimately controlling related infections and associated postharvest losses.

Polyamines Deficient Diet is a Complementary Strategy in Fighting Cancer: Analysis on Selected Medicinal Fruits

Polyamines are one of the oldest substances known in biochemistry consist of putrescine, spermidine and spermine. They are essential components of all living cells primarily involve in cell growth and proliferation. Upregulation of polyamines in human body is highly associated with various diseases, including cancer. Therefore, polyamines deficient diet (PDD) has become one of the strategies to inhibit carcinogenesis. This study was aimed to determine the polyamines content in selected anticancer fruits and their effect on polyamine polyamine metabolic enzymes was explored in human lung adenocarcinoma cells (A549). In this study, the selected medicinal fruits are Phoenix dactylifera (ajwa dates),Ficus auriculata (fig),Beta vulgaris (beetroot), Ziziphus jujube (jujube) and Vitis vinifera (raisin). The selected medicinal fruits were initially grouped into classes based on total polyamines content using High performance Liquid Chromatography (HPLC). The ability of selected fruits to reduce A549 intracellular polyamines was determined using the same technique. Accordingly, changes in polyamine metabolic enzymes activities; ornithine decarboxylase (ODC) and spermidine/spermine N-acetyltransferase (SSAT) were measured correspondingly using quantitative polymerase chain reactions (qPCR). Results suggested Beetroot, ajwa dates, fig and raisin are classified as low polyamines fruits while jujube demonstrates high content of polyamines. Significant decreased of total intracellular polyamine content after 24 h of treatments with these fruits were identified when compared with untreated A549 cells.Ornithine decarboxylase (ODC) activity showed downregulation upon treatment with ajwa dates, jujube and raisin while SSAT activity displayed alterations in beetroot and jujube treated A549 cells. Thus, we concluded that beetroot, ajwa dates, fig and raisins are the promising candidates for PDD strategy for their low polyamines, ability to reduce A549 intracellular polyamines and modification on ODC and SSAT activities.

The polyamine transporter Slc18b1(VPAT) is important for both short and long time memory and for regulation of polyamine content in the brain

SLC18B1 is a sister gene to the vesicular monoamine and acetylcholine transporters, and the only known polyamine transporter, with unknown physiological role. We reveal that Slc18b1 knock out mice has significantly reduced polyamine content in the brain providing the first evidence that Slc18b1 is functionally required for regulating polyamine levels. We found that this mouse has impaired short and long term memory in novel object recognition, radial arm maze and self-administration paradigms. We also show that Slc18b1 KO mice have altered expression of genes involved in Long Term Potentiation, plasticity, calcium signalling and synaptic functions and that expression of components of GABA and glutamate signalling are changed. We further observe a partial resistance to diazepam, manifested as significantly lowered reduction in locomotion after diazepam treatment. We suggest that removal of Slc18b1 leads to reduction of polyamine contents in neurons, resulting in reduced GABA signalling due to long-term reduction in glutamatergic signalling.

Exogenous polyamines enhance somatic embryogenesis and Agrobacterium tumefaciens-mediated transformation efficiency in sugarcane (Saccharum spp. hybrid)

The influence of exogenous polyamines (PAs) on somatic embryogenesis from immature leaf roll explants and Agrobacterium tumefaciens-mediated transformation of embryogenic callus of Saccharum spp. (sugarcane) ‘Co 86032’ was examined. Immature leaf roll-derived embryogenic callus was obtained on Murashige and Skoog with Gamborg B5 vitamins (MSB5) medium containing 3 mg L−1 2,4-dichlorophenoxyacetic acid (2,4-D). Various concentrations of PAs along with 2 mg L−1 2,4-D and 0.5 mg L−1 kinetin (Kin) were tested for somatic embryo induction. A total of 106 somatic embryos per 250 mg of callus (96.3% responsive explants) were obtained on medium supplemented with 20 mg L−1 putrescine (PUT) and 92.0% of the somatic embryos matured and produced 98 shoots per 250 mg of callus. Somatic embryo induction and maturation was increased more than two- and threefold, respectively, on PUT-supplemented medium compared to control cultures. Histomorphological analyses of various developmental stages verified somatic embryogenesis from immature leaf roll explants. The rooted plantlets were successfully hardened and exhibited normal growth. The efficiency of A. tumefaciens-mediated transformation of embryogenic callus using various concentrations of PAs in the infection, co-cultivation, and regeneration media was also assessed. Putrescine at 20 mg L−1 showed the highest regeneration (54.4%) and transformation (35.8%) efficiencies, which were more than twofold higher than the control treatment. These results demonstrate that exogenously supplied PAs improve plant regeneration using somatic embryogenesis and A. tumefaciens-mediated transformation of embryogenic callus of sugarcane ‘Co 86032’.

Changes in the activity of adenosine deaminase and the content of polyamines in the blood of cats with breast cancer

In this work, the clinical significance of changes in the activity of adenosine deaminase (ADA) and the content of polyamines in the blood plasma of cats with breast cancer was studied. There were examined 30 cats aged 1 to 20 years, operated on in veterinary clinics due to spontaneous neoplasms. Histological studies of surgical material were performed to establish nosological forms of the tumor. The results of the measurements showed that there were no significant differences between ADA activity in the blood plasma of cats diagnosed with invasive non-specific carcinoma and ADA activity in the blood of healthy animals. In the plasma of animals diagnosed with fibroadenomatous breast hyperplasia, ADA activity was reduced by 35% compared with the control group. The content of putrescine in the red blood cells of cats with benign neoplasms of the mammary gland (fibroepithelial hyperplasia) was statistically significantly increased 5 times compared with the control group. In malignant neoplasms of the mammary gland (invasive non-specific carcinoma, tubular cancer and fibrosarcoma), the content of putrescine and spermine in the blood significantly exceeded the control values by 60 and 10 times, respectively, compared with the control group. Thus, the data obtained indicate the possibility of using polyamines in order to improve the accuracy of diagnosis and treatment of cats with breast cancer. The determination of ADA activity in the blood plasma of cats with breast tumors in the early stages of cancer is not an informationally significant indicator as a tumor biomarker.