Spermidine Levels Research Articles

Arginine Supplementation Promotes Extracellular Matrix and Metabolic Changes in Keratoconus.

Keratoconus (KC) is a common corneal ectatic disease that affects 1:500–1:2000 people worldwide and is associated with a progressive thinning of the corneal stroma that may lead to severe astigmatism and visual deficits. Riboflavin-mediated collagen crosslinking currently remains the only approved treatment to halt progressive corneal thinning associated with KC by improving the biomechanical properties of the stroma. Treatments designed to increase collagen deposition by resident corneal stromal keratocytes remain elusive. In this study, we evaluated the effects of arginine supplementation on steady-state levels of arginine and arginine-related metabolites (e.g., ornithine, proline, hydroxyproline, spermidine, and putrescine) and collagen protein expression by primary human corneal fibroblasts isolated from KC and non-KC (healthy) corneas and cultured in an established 3D in vitro model. We identified lower cytoplasmic arginine and spermidine levels in KC-derived constructs compared to healthy controls, which corresponded with overall higher gene expression of arginase. Arginine supplementation led to a robust increase in cytoplasmic arginine, ornithine, and spermidine levels in controls only and a significant increase in collagen type I secretion in KC-derived constructs. Further studies evaluating safety and efficacy of arginine supplementation are required to elucidate the potential therapeutic applications of modulating collagen deposition in the context of KC.

Spermidine and spermine exert protective effects within the lung.

Asthma is a heterologous disease that is influenced by complex interactions between multiple environmental exposures, metabolism, and host immunoregulatory processes. Specific metabolites are increasingly recognized to influence respiratory inflammation. However, the role of protein‐derived metabolites in regulating inflammatory responses in the lung are poorly described. The aims of the present study were to quantify polyamine levels in bronchoalveolar lavages (BALs) from healthy volunteers and asthma patients, and to evaluate the impact of each polyamine on inflammatory responses using in vitro models and in a house dust mite (HDM)‐induced respiratory allergy model. Spermidine levels were decreased, while cadaverine levels were increased in BALs from asthma patients compared to healthy controls, using Ultra Performance Liquid Chromatography (UPLC). Both spermine and spermidine inhibit lipopolysaccharide (LPS)‐induced cytokine secretion from human peripheral blood mononuclear cells (PBMCs) and dendritic cells (DCs) in vitro. In addition, oral gavage with spermine or spermidine modulate HDM‐induced cell infiltration, cytokine secretion, and epithelial cell tight junction expression in murine models. Spermidine also reduces airway hyper‐responsiveness. These results suggest that modulation of polyamine metabolism, in particular spermidine, is associated with respiratory inflammation and these molecules and pathways should be further explored as biomarkers of disease and potential targets for novel therapies.

Relationship between Micromolecules and Quality Changes of Tilapia Fillets after Partial Freezing Treatment with Polyphenols.

The study investigated the main characteristic micromolecular changes in tilapia fillets after partial freezing treatment with polyphenols by ultrahigh-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) analysis. A total of 2121 metabolite ion features were identified. The result suggested that procyanidin treatment increased the sweet, salty, and thick peptides' contents and suppressed the formation of bitter peptides. The levels of cis-4-octenedioic acid, 2-amino-heptanoic acid, indoleacrylic acid, and 2-amino-3-methyl-1-butanol in polyphenol treatments were significantly lower compared to those in the control group (P < 0.05), which delayed the formation of micromolecule of acids and alcohols associated with spoilage and inhibited the protein and lipid oxidation and degradation. Polyphenol treatments suppressed the formation of biogenic amines (lower levels of spermidine and 1-naphthylacetylspermine) and reduced fillet quality deterioration. It provided critical novel insights into the understanding of the molecular mechanism for inhibiting the quality deterioration of fillets treated with polyphenols during storage.

Exogenous Nitric Oxide Confers Tolerance to Cr(VI) in Maize (Zea mays L.) Seedlings by Modulating Endogenous Oxido-Nitrosative Events

The use of exogenous compounds such as ‘gasotransmitter’ molecules is a well-established agronomic strategy to improve the crop tolerance to environmental stresses. In this current work, when Cr (200 µM) was combined with the nitric oxide (NO) generator sodium nitroprusside SNP, 500 µM) there was a suppression of metal-induced alterations in embryo growth. Exogenous NO produced by SNP reduced the accumulation of toxic hydrogen peroxide and methylglyoxal and stress-linked proline in Cr-treated seedlings. Chromium increased thiol and S-nitrosothiol levels but this was restored to control levels by SNP, in spite of a competing NO reaction leading to increase of S-nitrosoglutathione content. However, added complexity was indicated by addition of arginine analogue N (ω)-nitro-L-arginine methyl ester (L-NAME, 500 µM) in the germinating medium to suppress endogenous NO production. This suppressed endogenous NO production but superoxide dismutase (SOD) was suppressed not enhanced in Cr + L-NAME treatments. In addition, Cr + L-NAME significantly decreased the content of spermidine and spermine in epicotyls as compared to Cr treatment alone. Similarly, exposure to Cr + SNP decreased spermidine and spermine levels in both radicles and epicotyls. This is important as polyamines have been suggested as route for NO production. Thus, our observations suggest that exogenous NO mitigates Cr-induced damage and confers seedling tolerance to Cr through suppression of NADPH oxidase activity and increased GSNO contents. This may act to prevent an excess of methylglyoxal and hydrogen peroxide. However, the reduction in polyamine mediated cellular NO generation could also promote increased viability under Cr stress.

Trehalose can alleviate decreases in grain number per spike caused by low‐temperature stress at the booting stage by promoting floret fertility in wheat

AbstractAlleviating the negative effects of low temperature at the booting stage on wheat grain number and yield is important for maintaining high and stable wheat yields. In this study, we selected wheat varieties with different levels of cold resistance, simulated low temperature at the booting stage and exogenously applied trehalose to study its effect on wheat floret development under low‐temperature stress and explore the physiological mechanism of that process. The results showed that higher levels of endogenous trehalose benefited wheat resistance to low‐temperature stress. Exogenous trehalose inhibited floret degeneration and increased floret fertility in the apical spikelets, thus significantly alleviating the decrease in grain number per spike caused by low temperature. The results of the metabolomics analysis as well as the physiological indexes showed that trehalose significantly promoted the assimilation of nitrogen in florets under low‐temperature stress, thus reducing the accumulation of ammonium ions in the plant cells. In addition, exogenous trehalose significantly increased the endogenous spermidine level in florets, increased their glutathione and ascorbic acid contents, promoted the glutathione‐ascorbic acid cycle, and thereby reduced the contents of reactive oxygen species in florets. This may be an important physiological mechanism by which trehalose alleviates the effect of low‐temperature stress on floret development in wheat.

Exogenous melatonin regulates endogenous phytohormone homeostasis and thiol-mediated detoxification in two indica rice cultivars under arsenic stress.

Melatonin enhanced arsenic (As) tolerance by inhibiting As bioaccumulation, modulating the expression of As transporters and phytohormone homeostasis, leading to efficient utilization of thiol machinery for sequestration and detoxification of this toxic metalloid. The present study was aimed at investigating the influence of exogenous melatonin on the regulation of endogenous plant growth regulators and their cumulative effects on metal(loid)-binding ligands in two contrasting indica rice cultivars, viz., Khitish (arsenic sensitive) and Muktashri (arsenic tolerant) under arsenic stress. Melatonin supplementation ameliorated arsenic-induced perturbations by triggering endogenous levels of gibberellic acid and melatonin, via up-regulating the expression of key biosynthetic genes like GA3ox, TDC, SNAT and ASMT. The endogenous abscisic acid content was also enhanced upon melatonin treatment by induced expression of the key anabolic gene, NCED3 and concomitant suppression of ABA8ox1. Enhanced melatonin content induced accumulation of higher polyamines (spermidine and spermine), together with up-regulation of SPDS and SPMS in Khitish, thereby modulating stress condition. On the contrary, melatonin escalated putrescine and spermidine levels in Muktashri, via enhanced expression of ADC and SAMDC. The role of melatonin appeared to be more prominent in Khitish, as evident from better utilization of thiol components like cysteine, GSH, non-protein thiols and phytochelatins, with higher GSH/GSSG ratio, despite down-regulated expression of corresponding thiol-metabolic genes (OsMT2 and OsPCS1) to deal with arsenic toxicity. The extent of arsenic bioaccumulation, which was magnified several folds, particularly in Khitish, was decreased upon melatonin application. Overall, our observation highlighted the fact that melatonin enhanced arsenic tolerance by inhibiting arsenic bioaccumulation, via modulating the expression levels of selected arsenic transporters (OsNramp1, OsPT2, OsPT8, OsLsi1) and controlling endogenous phytohormone homeostasis, leading to efficient utilization of thiol machinery for sequestration and detoxification of this toxic metalloid.

Exogenous melatonin alleviated chilling injury in harvested plum fruit via affecting the levels of polyamines conjugated to plasma membrane

Polyamines (PAs) are related closely with many abiotic stresses. However, conjugated PA functions are not clear in alleviating chilling injury in fruit. The contents of free PAs in plum flesh cell and conjugated PAs in plasma membrane (PM), the activities of S-adenosylmethionine decarboxylase (SAMDC) and transglutaminase (TGase), and the degree of chilling injury were investigated in harvested plum (Prunus salicina L.) fruit pre-treated with exogenous melatonin. Chilling treatment resulted in the injury of plasma membrane (PM), as judged by the increased PM permeability, chilling injury index and malondialdehyde (MDA) content, and the decreased sulfhydryl group contents. Exogenous melatonin alleviated chilling injury, in parallel with the increased levels of free spermidine (Spd) and spermine (Spm) in cell, conjugated non-covalently (CNC) Spd and Spm, and conjugated covalently (CC) Put and Spd in PM, resulting from the increased activities of SAMDC and TGase. The results of the additional experiments with two inhibitors, methylglyoxyl-bis (guanylhydrazone) (MGBG) and phenanthrolin, which inhibit the activities of SAMDC and TGase, respectively, were complementary evidences for our research. MGBG and TGase treatment decreased the level of CNC PAs (Spd and Spm) and CC PAs (Put and Spd), respectively, coupled with aggravating the chilling injury. From these above mentioned-results, it could be suggested that exogenous melatonin alleviated chilling injury by elevating the levels of CNC Spd, CNC Spm, CC Put and CC Spd in PM.

Effect of Pretreatment Processes on Biogenic Amines Content and Some Bioactive Compounds in Hericium erinaceus Extract.

Hericium erinaceus is reported as a source of several nutritional contents and bioactive compounds, especially β-glucan. However, various uncontrolled processes lead to the formation of byproducts that can affect human health, including biogenic amines. These amines are concerning, because their presence is an important indicator of the process of hygiene and food spoilage or quality. A better understanding of various pretreatment processes can control the content of biogenic amines. In this work, we studied the effect of pretreatment processes, i.e., sample size (whole, ripping, and chopping); heating process (non-heating, blanching, and boiling); and drying method (nondrying, hot air drying, and freeze-drying) on biogenic amine contents in H. erinaceus extract. A method of the post-column high-performance liquid chromatography (HPLC) technique was used for the analysis of putrescine (PUT) and spermidine (SPD) in H. erinaceus extract following the acceptable guidelines. In this study, treatment 20 (chopping/non-heating/hot air drying) was suggested as a good choice for the pretreatment process, because low levels of PUT and SPD were shown in the extract while high levels of the bioactive compounds β-glucan and antioxidant activity were presented. This treatment process can be applied to the industry because of its easy operation and cost-saving.

Insight into the Metabolite Pattern of Psoriasis: Correlation among Homocysteine, Methionine, and Polyamines

Psoriasis is an incurable dermatological disorder, characterized by increased epidermal cell proliferation. Numerous studies have focused on the modulation of polyamine (PA) metabolism in psoriatic lesions, as well as the relationship between serum homocysteine (Hcy) levels and psoriasis severity. The correlation between Hcy and PA levels has not been investigated, although both of them depend on methionine (Met) loading. The aim of this study was to examine Met, Hcy, and polyamine levels in serum, saliva, lesions, and non-affected skin to investigate the eventual relationship between their levels in skin samples and to assess the correlation of each metabolite among the tested samples. This study was conducted on 24 patients with plaque-form psoriasis vulgaris. The original LC-MS/MS method was used for quantification of analytes. Hyperhomocysteinemia was observed and the serum levels of spermidine (Spd) and spermine (Spm) were also found to be elevated. A significant increase in Met (p &lt; 0.05) and Spm (p &lt; 0.001) concentrations in the psoriatic plaques were found, when compared to the non-affected skin. Significant correlations were established between all polyamines levels and between methionine and spermine in both types of cutaneous samples. This study illustrates the tight relationship between Met and Polyamine levels in epidermis of psoriatic patients. Our results could be helpful in psoriasis treatment, highlighting the importance of the balanced protein diet and intake of vitamins B12 and B9.

Spermidine at supraphysiological doses induces oxidative stress and granulosa cell apoptosis in mouse ovaries

Given that spermidine is associated with aging-related diseases and it is a potential target for delaying aging, functional studies on supraphysiological levels of spermidine are required. Our previous studies showed that the granulosa layer arranged irregular and the follicular oocytes were shrunk in female mice injected intraperitoneally with spermidine at 150 mg/kg (Body weight) after 24 h. It indicated that supraphysiological levels of spermidine induced ovarian damage in female mice. The objective of this study was to investigate the effect of acute administration of supraphysiological spermidine on the ovary and granulosa cells in mice. The results showed that treatment with spermidine at 150 mg/kg (intraperitoneal) significantly increased the levels of both H2O2 and malondialdehyde and reduced total antioxidant capacity and the activities of catalase and superoxide dismutase in mouse ovaries. The contents of putrescine and spermine increased significantly in the ovaries of mice treated with spermidine. Treatment with spermidine at 150 mg/kg increased the apoptotic rate and reactive oxygen species levels of granulosa cells in mouse ovaries. Furthermore, the protein expression of P53, CASPASE 8 (Cleaved/Pro), CASPASE 9 (Cleaved/Pro) and CASPASE 3 (Cleaved/Pro) in granulosa cells of mice treated with spermidine were significantly upregulated, while BCL2 expression was significantly downregulated. In summary, our study demonstrates for the first time that spermidine at supraphysiological doses causes ovarian oxidative stress and induces granulosa cell apoptosis via the P53 and/or BCL2-CASPASEs pathway.

SPERMIDINE MAINTAINS TELOMERE LENGTH AND DELAYS AGING

Spermidine, a natural polyamine, has been noticed for its anti-aging properties. Supplementation of this drug prolongs lifespan and diminishes the incidence of age-related pathology. In the human population, spermidine levels decrease as aging progresses, and a potential link between diminished endogenous spermidine levels and age-related declination has been studied. At the cellular level, autophagy is the prime mode of action of spermidine known to decline with the progress of aging, similarly contributing to the accretion of impaired macromolecules and organelles through aging. Epidemiological statistics support the concept, suggesting that elevated uptake of polyamine delays aging. Here, we overview the effect of autophagy on cellular processes and age-associated diseases, emphasizing the importance of these events to the hallmarks of aging.&#x0D; There are numerous factors like shortening telomere, oxidative stress, mitochondrial damage, and impaired intracellular calcium signaling, which are influenced by the aging process. We hypothesize that spermidine supplements in the diet increase the telomere length. The proposed hypothesis also brings to light the differentially regulated genes involved in telomere maintenance and aging after spermidine treatment. Knowing the role of spermidine in telomere maintenance would help us understand the molecular mechanism of spermidine's effect on aging.

EIF5A hypusination, boosted by dietary spermidine, protects from premature brain aging and mitochondrial dysfunction.

Mitochondrial function declines during brain aging and is suspected to play a key role in age-induced cognitive decline and neurodegeneration. Supplementing levels of spermidine, a body-endogenous metabolite, has been shown to promote mitochondrial respiration and delay aspects of brain aging. Spermidine serves as the amino-butyl group donor for the synthesis of hypusine (Nε-[4-amino-2-hydroxybutyl]-lysine) at a specific lysine residue of the eukaryotic translation initiation factor 5A (eIF5A). Here, we show that in the Drosophila brain, hypusinated eIF5A levels decline with age but can be boosted by dietary spermidine. Several genetic regimes of attenuating eIF5A hypusination all similarly affect brain mitochondrial respiration resembling age-typical mitochondrial decay and also provoke a premature aging of locomotion and memory formation in adult Drosophilae. eIF5A hypusination, conserved through all eukaryotes as an obviously critical effector of spermidine, might thus be an important diagnostic and therapeutic avenue in aspects of brain aging provoked by mitochondrial decline.

Survey of biogenic amines (histamine and spermidine) in commercial seafood by enzyme linked immunosorbent assay (ELISA)

Introduction Worldwide there is serious concern about food and consumer safety [1], namely with seafood products. Consequently, there is a major concern regarding food spoilage which make them unsuitable for human consumption. When deteriorating, seafood products suffers a complex series of events that begins when the organism die [1,2]. Therefore, there is a strong need for developing reliable seafood quality analysis. In the present study we surveyed histamine and spermidine in several seafood products (fresh fish and clams), purchased in a Portuguese traditional market. Materials and methods Fresh seafood (Sardina pilchardus, Trachurus trachurus, Sparus aurata and Ruditapes decussata) were purchased in a market and taken to the laboratory in refrigerated containers. A total of 10 specimens were sampled from each species. Then samples were processed for analysis by homogenising in a phosphate buffer saline solution, centrifuged (10,000×g at 4 °C) for 15 min) and then stored at –80 °C until analysis. Seafood samples were assessed for the presence and content of histamine and spermidine using an indirect Enzyme Linked Immunosorbent assay (ELISA) [3]. The statistical analysis was performed using the Mann–Whitney U-test to determine differences between biogenic amine levels in seafood samples. Statistics was performed with a significance level of 5%, using the software Statistica 8.0 (Statsoft, Tulsa, OK, USA). Results The results show variable results between species (from < LD to 184104 mg histamine/Kg wet weight). The highest levels were detected in T. trachurus samples and the lowest in clams. However, it was possible to detect the presence of the selected biogenic amines (histamine and spermidine) in most samples analysed. The lowest levels of spermidine were determined in R. decussata (1504.43 mg/kg w.w.), while the highest levels were determined in T. trachurus (184104 mg/Kg w.w.). Regarding histamine, the lowest levels were determined in R. decussata 20.23 mg/Kg w.w.) and the highest levels were measured in T. trachurus (460.25 mg/kg w.w.). Discussion and conclusions Although we are capable to detect the presence of the selected biogenic amines, in most of the samples the levels were below the limits established by Food and Drug Administration [4] and the European Union Commission Regulation (EC) No 1441/2007 [5].

Spermidine supplementation in rare translation-associated disorders.

The polyamine spermidine is essential for protein translation in eukaryotes, both as a substrate for the hypusination of the translation initiation factor eIF5A as well as general translational fidelity. Dwindling spermidine levels during aging have been implicated in reduced immune cell function through insufficient eIF5A hypusination, which can be restored by external supplementation. Recent findings characterize a group of novel Mendelian disorders linked to EIF5A missense and nonsense variants that cause protein translation defects. In model organisms that recapitulate these mutations, spermidine supplementation was able to alleviate at least some of the concomitant protein translation defects. Here, we discuss the role of spermidine in protein translation and possible therapeutic avenues for translation-associated disorders.

Assessment of biogenic amines profile in ciders from the Central Europe region as affected by storage time

The aim of the research was the assessment of 8 biogenic amines occurrence (BA) in ciders. Forty samples with ethanol content ≤4.5% v/v (LC; low alcohol content) and 34 samples with ethanol content > 4.5% v/v (HC; high alcohol content) manufactured in the Central Europe region were tested. The cider samples were immediately analyzed after purchase and at the end of the best before date. The most abundant BA across all ciders was tyramine, followed by putrescine and cadaverine (p < 0.05). Samples reported low levels of tryptamine, spermidine, spermine, histamine and phenylethylamine. No cider at the end of the best before date had a sum of BA below <5 mg l−1. Moreover, 67% of the samples at the beginning of the storage period and 47% of the ciders after the best before date presented a total BA content in the range of 5–20 mg l−1. A total number of 14% of the samples immediately after purchase and 31% of samples at the end of the best before date showed a BA concentration in the range of 20–50 mg l−1. The BA content of 16 samples was >50 mg l−1 at the end of the best before date. However, one LC cider and two HC products displayed a BA sum of nearly 120 mg l−1. In general, higher concentrations of tyramine, cadaverine and putrescine were detected in LC samples. All in all, with the prolonging of storage the BA concentration increased.

AMD1 upregulates hepatocellular carcinoma cells stemness by FTO mediated mRNA demethylation.

BackgroundS‐adenosylmethionine decarboxylase proenzyme (AMD1) is a key enzyme involved in the synthesis of spermine (SPM) and spermidine (SPD), which are associated with multifarious cellular processes. It is also found to be an oncogene in multiple cancers and a potential target for tumor therapy. Nevertheless, the role AMD1 plays in hepatocellular carcinoma (HCC) is still unknown.MethodsHCC samples were applied to detect AMD1 expression and evaluate its associations with clinicopathological features and prognosis. Subcutaneous and orthotopic tumor mouse models were constructed to analyze the proliferation and metastasis of HCC cells after AMD1 knockdown or overexpression. Drug sensitive and tumor sphere assay were performed to investigate the effect of AMD1 on HCC cells stemness. Real‐time quantitative PCR (qRT‐PCR), western blot, immunohistochemical (IHC) and m6A‐RNA immunoprecipitation (Me‐RIP) sequencing/qPCR were applied to explore the potential mechanisms of AMD1 in HCC. Furthermore, immunofluorescence, co‐IP (Co‐IP) assays, and mass spectrometric (MS) analyses were performed to verify the proteins interacting with AMD1.ResultsAMD1 was enriched in human HCC tissues and suggested a poor prognosis. High AMD1 level could promote SRY‐box transcription factor 2 (SOX2), Kruppel like factor 4 (KLF4), and NANOG expression of HCC cells through obesity–associated protein (FTO)‐mediated mRNA demethylation. Mechanistically, high AMD1 expression increased the levels of SPD in HCC cells, which could modify the scaffold protein, Ras GTPase‐activating‐like protein 1 (IQGAP1) and enhance the interaction between IQGAP1 and FTO. This interaction could enhance the phosphorylation and decrease the ubiquitination of FTO.ConclusionsAMD1 could stabilize the interaction of IQGAP1 with FTO, which then promotes FTO expression and increases HCC stemness. AMD1 shows prospects as a prognostic predictor and a therapeutic target for HCC.

Derangement of hepatic polyamine, folate, and methionine cycle metabolism in cystathionine beta-synthase-deficient homocystinuria in the presence and absence of treatment: Possible implications for pathogenesis

Cystathionine beta-synthase deficient homocystinuria (HCU) is a life-threatening disorder of sulfur metabolism. Our knowledge of the metabolic changes induced in HCU are based almost exclusively on data derived from plasma. In the present study, we present a comprehensive analysis on the effects of HCU upon the hepatic metabolites and enzyme expression levels of the methionine-folate cycles in a mouse model of HCU.HCU induced a 10-fold increase in hepatic total homocysteine and in contrast to plasma, this metabolite was only lowered by approximately 20% by betaine treatment indicating that this toxic metabolite remains unacceptably elevated. Hepatic methionine, S-adenosylmethionine, S-adenosylhomocysteine, N-acetlymethionine, N-formylmethionine, methionine sulfoxide, S-methylcysteine, serine, N-acetylserine, taurocyamine and N-acetyltaurine levels were also significantly increased by HCU while cysteine, N-acetylcysteine and hypotaurine were all significantly decreased. In terms of polyamine metabolism, HCU significantly decreased spermine and spermidine levels while increasing 5′-methylthioadenosine. Betaine treatment restored normal spermine and spermidine levels but further increased 5′-methylthioadenosine.HCU induced a 2-fold induction in expression of both S-adenosylhomocysteine hydrolase and methylenetetrahydrofolate reductase. Induction of this latter enzyme was accompanied by a 10-fold accumulation of its product, 5-methyl-tetrahydrofolate, with the potential to significantly perturb one‑carbon metabolism. Expression of the cytoplasmic isoform of serine hydroxymethyltransferase was unaffected by HCU but the mitochondrial isoform was repressed indicating differential regulation of one‑carbon metabolism in different sub-cellular compartments. All HCU-induced changes in enzyme expression were completely reversed by either betaine or taurine treatment. Collectively, our data show significant alterations of polyamine, folate and methionine cycle metabolism in HCU hepatic tissues that in some cases, differ significantly from those observed in plasma, and have the potential to contribute to multiple aspects of pathogenesis.

The combined supplementation of omega-3 fatty acids and probiotics decreased the levels of serum polyamines in experimental colitis

Polyamines play an important role in the maintenance of intestinal permeability. Therefore we aimed to determine the effects of probiotics and omega 3 fatty acids on serum polyamine levels in colitis. Fifty BALB/c mice were randomly grouped as normal, colitis with no treatment applied, colitis treated by probiotics (VSL#3), colitis treated by omega-3, and colitis treated by both probiotics and omega-3. Experimental colitis was induced by injection of 200 mg/kg 2,4-Dinitrobenzenesulfonic acid (DNBS). The probiotic and the omega-3 fatty acid supplements were applied daily by oral gavage. Serum polyamine levels were measured with high performance liquid chromatography (HPLC). In each group, the levels of serum polyamines are the highest in spermidine and the least in spermine. Bowel inflammation in experimentally induced colitis mice resulted in lower serum polyamine concentrations. In probiotic and omega 3 fatty acid supplemented group significant decreases were observed for spermine and spermidine (p&lt;0.001), while no significant changes were obtained for putrescine. Combined supplementation of probiotics and omega-3 fatty acids for 10 days in colitis mice significantly decreased the serum levels of spermine and spermidine.

The impact of storage duration and conditions on the formation of biogenic amines and microbial content in poultry meat

This research was conducted to estimate the safety of breast and thigh meat (Ross 308) stored in refrigeration and freezing for different periods (0, 3 and 6) and (0, 15 and 30) days, respectively (total samples 12). High pH found in the 6th day of refrigeration storage for thigh meat; 6.414, while low recorded in the 6th day for breast meat; 5.757. High pH was found in the freezing storage period 0 day for chicken breast meat; 6.168, and low pH was found in breast meat in the 30th day of freezing storage; 5.826. The 6th day of refrigeration storage gave the highest TPC for thigh meat; 111.33×106 cfu/ gm. Also, the 15th day of freezing storage recorded significant increase in TPC for breast and thigh meat; 244×105 cfu/ gm and 274×105 cfu/ gm respectively. Significant differences were noted for histamine, cadaverine and spermidine during storage periods, high levels recorded in the 6th day of storage for breast meat; 0.395, 0.078 and 0.643 mg/ kg respectively. Significant differences were noted between the mean levels of biogenic amines for breast samples during all storage periods. High levels of histamine, putrescine, cadaverine, spermine and spermidine were recorded in the 15h day of storage; 2.654, 0.358, 1.589, 0.124 and 2.652 mg/ kg respectively. In thigh meat, significant differences were recorded for levels of biogenic amines during the freezing storage periods except putrescine. Histamine did not exceed the legal limit set by the US FDA; 50 mg/ kg in all samples.

Effects of alkali stress on dry matter accumulation, root morphology, ion balance, free polyamines, and organic acids of sugar beet

Sugar beet is strongly resistant to salt-alkalinity. Understanding the physiological alkali stress resistance mechanism of sugar beet is important for fully utilizing saline–alkaline soil. Sugar beet seedlings from cultivars KWS0143 (alkali-tolerant) and Beta464 (alkali-sensitive) were treated with five concentrations of mixed alkaline solutions (NaHCO3: Na2CO3, 2:1), namely, 0 (control), 25, 50, 75, and 100 mM (mole concentration was calculated in Na+). A sharper decrease in dry weight per plant (87.1%) and total root length (91.7%) of Beta464 were observed compared to the 61.5% and 85.0% decrease in those of KWS0143 under 100 mM alkali treatment. With increasing alkaline stress, Na+ accumulation hindered K+ and Ca2+ absorption by roots. Free polyamines contents and phosphoenolpyruvate carboxylase (PEPC) activity in roots of both cultivars were all significantly enhanced by 50 and 75 mM alkali treatments. KWS0143 exhibited higher dissociated putrescine (Put), spermine (Spm), as well as spermidine (Spd) levels within the roots compared to Beta464 under alkali conditions. Root free Spd contents of KWS0143 and Beta464 increased by 154.2 and 64.5% treated with 50 mM alkali in comparison with the control. After treated with the dose of 25 mM, root succinic acid (SA) contents of KWS0143 and Beta464 increased by 90.4 and 14.3%, respectively, compared to the plants subjected to the control. Our results imply that polyamines and PEPC contribute to the tolerance of sugar beet to alkali stress. Those results could be useful for enriching the theory of plant stress response.