Diamino Oxidase Research Articles

Observational study to assess the efficacy and safety of diaminooxidase (DAO) supplementation in patients with histamine intolerance (HIT)

Observational study to assess the efficacy and safety of diaminooxidase (DAO) supplementation in patients with histamine intolerance (HIT)

Excessive dietary soluble arabinoxylan impairs the intestinal physical and immunological barriers via activating MAPK/NF-κB signaling pathway in rainbow trout (Oncorhynchus mykiss)

Arabinoxylan (AX) has been deemed as an antinutritional factor, but limited information has addressed the effects of dietary AX on intestinal health of fish. The present study investigated the effects of dietary AX on intestinal mucosal physical and immunological barriers of rainbow trout (Oncorhynchus mykiss). Five isoproteic and isolipidic experimental diets (AXE, AX0, AX2.5, AX5 and AX10) were formulated to contain 0.03% arabinoxylanase as well as 0%, 2.5%, 5% and 10% AX, respectively. Each diet was randomly distributed to triplicate groups of 35 juvenile (average weight 3.14 ± 0.02 g) per tank in a rearing system maintained at 17 ± 1 °C for 9 weeks. Dietary AX supplementation regardless of inclusion levels significantly (P < 0.05) depressed the growth performance and feed utilization. The plasma endothelin-1 and d-lactic acid contents as well as diamino oxidase activity were significantly higher in fish fed diet AX10 compared to fish fed diet AX0. Dietary inclusion of 5–10% AX resulted in decreased intestinal villus height, goblet cell number and desmosome density, increased crypt depth, short and irregular microvilli, widened intercellular space; down-regulated the mRNA levels of occludin in hindgut, claudin3 and ZO-1 in foregut and midgut, but up-regulated the mRNA levels of claudin12 and claudin15 in midgut as well as claudin23 in foregut, midgut and hindgut. Furthermore, dietary 5–10% AX supplementation decreased the midgut and hindgut complement 3, complement 4 and sIgT contents as well as the midgut IgM and hindgut IL-10 contents. Conversely, the hindgut TNF-α and IL-6 contents increased with the rising dietary AX level. RT-qPCR demonstrated that the pro-inflammatory cytokines (IL-1β, IL-6, IL-8, IL-12β, IFN-γ, and TNF-α) and pIgR mRNA levels in midgut and hindgut were up-regulated by dietary AX inclusion of 5–10% AX. Meanwhile, the mRNA levels of p38 MAPK, IκBα, and NF-κB p65 in midgut and hindgut raised gradually with the increasing dietary AX content. The Western blot results showed that the protein expression levels of p38 MAPK and NF-κB generally increased with the rising dietary AX content. Dietary treatment with 0.03% arabinoxylanase did not affect the growth performance and intestinal health of rainbow trout (P > 0.05). In conclusion, excessive dietary AX inclusion (5–10%) increased the intestinal permeability and induced the intestinal inflammatory response via activating MAPK/NF-κB signaling pathway, and ultimately damaged the intestinal barrier function of rainbow trout.

Placebo-Controlled Histamine Challenge Disproves Suspicion of Histamine Intolerance

Histamine intolerance (HIT) is frequently diagnosed in patients with polysymptomatic otherwise unexplained symptoms. To exclude HIT by a single-blind placebo-controlled histamine challenge (SBPCHC), to study clinical features of patients with positive challenge, and to examine the predictability of HIT by biomarkers. SBPCHC was performed in 59 patients with suspected HIT. History and clinical data, including serum diamine oxidase (DAO) and histamine skin test wheal size of patients with positive versus negative SBPCHC, were compared. Patients were predominantly middle-aged women (84.7%). Three-quarters reported improvement but never resolution of symptoms during a histamine-low diet. Histamine provocation was safe; only 1 patient was treated with antihistamines. Thirty-seven patients (62.7%) displayed symptoms to placebo. HIT was excluded in 50 patients (84.7%). Objective symptoms occurred in 4 of 59 cases (6.8%) after histamine but not after placebo challenge. These were diagnosed with "plausible HIT" because reactions occurring by chance could not be excluded. Another 5 patients (8.5%) were diagnosed with "possible HIT" after case-dependent detailed analysis. Patients with plausible/possible HIT had reported more gastrointestinal symptoms (P= .01), but comparable diet response and equal histamine skin prick test wheal sizes to those without HIT. Serum DAO activity tended to be lower in patients with HIT (P= .08), but was highly variable in those without, limiting its value as a biomarker. SBPCHC disproves HIT in the majority of patients. Placebo-controlled challenges are needed as placebo reactions were frequent. Gastrointestinal symptoms after food intake and reduced DAO levels are markers for HIT; however, specificity is not sufficient enough for making the diagnosis.

Isolation, purification and characterization of Pueraria lobata polysaccharide and its effects on intestinal function in cyclophosphamide-treated mice

This study investigated the structure of acidic Pueraria lobata polysaccharide (a-PLP) and its bioactive effects on intestinal function in cyclophosphamide (CY)-treated mice. The structure of a-PLP was preliminarily analyzed, and the results showed that it is composed of fucose, arabinose, rhamnose, galactose, glucose, xylose, mannose, galacturonic acid, and glucuronic acid in a molar proportion of 2.54:16.52: 6.14: 16.60: 4.05: 4.75: 0.48: 47.44: 1.47 with a weight average molecular weight of 22.675 kDa. In addition, the methylation analysis suggested that 4-Gal(p)-UA may be the main backbone of a-PLP. Furthermore, a-PLP (1.2 g/kg, 0.8 g/kg, and 0.4 g/kg) was administered orally for the treatment of CY-treated mice. The results showed that a-PLP could remarkably relieved weight loss and intestinal villous atrophy in CY-treated mice. Meanwhile, the secretion levels of sIgA, β-defensin, cytokines, Mucin-2, and tight junction proteins increased significantly. Moreover, the ratio of T (CD4+ and CD8+) cells in the Peyer's patches and mesenteric lymph nodes also increased remarkably, along with the number of goblet cells. Furthermore, a-PLP decreased the levels of diamino oxidase and malondialdehyde, but up-regulated the activity of superoxide dismutase. In summary, a-PLP exhibited great benefits by attenuating CY side effects, opening a potential avenue to effectively treat cancer and reduce the suffering of chemotherapy patients.

Histamine intolerance and anxiety disorders: pilot cross-sectional study of histamine intolerance prevalence in cohort of patients with anxiety disorders

IntroductionHistamine intolerance (HI) is a disorder associated with an impairment of ability to metabolize ingested histamine. The incidence of HI in general population is 1-3%. Clinical manifestation of HI contains nonspecific predominantly gastrointestinal, but also extraintestinal symptoms. HI could be primary with genetic predisposition, or secondary with lower activity of diaminooxidase (DAO) without positive genetic screening.ObjectivesThis study aims to evaluate the prevalence of HI by patients with anxiety disorders. HI can imitate anxiety symptoms, therefore we predict higher prevalence HI in patients with anxiety disorders than in general population.MethodsIt is observational cross-sectional study on cohort of anxious patients for detecting the prevalence of HI. Patients were screened by scale for histamine intolerance questionnaire. Patients with positive questionnaire were examined for serum DAO and genetically examined.Results113 patients fulfilled the HI questionnaire. From this cohort 35.4% (40 subjects) were positive at screening. Biomarkers of HI were screened only in case of positivity in this questionnaire. Table No. 1: Results of our study from cohort with positive screening, 35.4 % (40 subjects).Genetic predispositionpositivity in risk allelenegativity in risk allelealtogetherSerum level of DAOpositive screening (DAO&lt;10 U/ml)5 (4.4%)primary-genetically determined HI5 (4.4%)secondary HI10negative screening (DAO≥10 U/ml)14 (12.4%)16 (14.2%)30altogether1921ConclusionsThis pilot study shows that the prevalence of HI could be higher in group of patients with anxiety disorders than in general population. For further confirmation other studies with control group and larger cohort should be done.DisclosureNo significant relationships.

Co-functioning of 2AP precursor amino acids enhances 2-acetyl-1-pyrroline under salt stress in aromatic rice (Oryza sativa L.) cultivars

Aromatic rice (Oryza sativa) fetches a premium price due to the pleasant aroma. The major aroma compound 2-acetyl-1-pyrroline (2AP) has been found to be enhanced under stress. This condition can be considered to study the genes, precursors, enzymes, and metabolites involved in elevated levels of 2AP biosynthesis. In the present study, 100 mM salt treatment was given to two aromatic rice cultivars Ambemohar-157 (A-157) and Basmati-370 (B-370) at the vegetative stage (VS3). After salt treatment, in the leaves, 2AP contents were elevated by 2.2 and 1.8 fold in A-157 and B-370, respectively. Under these elevated 2AP conditions, the precursor amino acids (glutamate, putrescine, ornithine, and proline), their related genes, enzymes, and metabolites (methylglyoxal and γ-aminobutyric acid (GABA) related to 2AP biosynthesis were analyzed. In addition, agronomic characters were also studied. It was observed that the proline content was enhanced in both the cultivars by 29% (A-157) and 40% (B-370) as compared to control. The Δ1-pyrroline-5-carboxylate synthetase (P5CS) enzyme activity was increased in salt-treated plants leaf tissue by 31% (A-157) and 40% (B-370) compared to control. The P5CS gene expression was enhanced by A-157 (1.8 fold) and B-370 (2.2 fold) compared to control, putrescine content in A-157 and B-370 decreased by 2.5 and 2.7 fold respectively as compared to control. The ornithine decarboxylase (ODC) activity was enhanced in A-157 (12%) and B-370 (35%) over control. Further, ODC gene expression was enhanced in both the cultivars A-157 (1.5 fold) and B-370 (1.3 fold). The diamino oxidase (DAO) enzyme activity was increased by 28% (A-157) and 35% (B-370) respectively over control. The GABA content marginally increased over control in both the cultivars namely, A-157 (1.9%) and B-370 (9.5%). The methylglyoxal levels were enhanced by 1.4 fold in A-157 and 1.6 fold in B-370. Interestingly, the enhancement in 2AP in the vegetative stage also helped to accumulate it in mature grains (twofold in A-157 and 1.5 fold in B-370) without test weight penalty. The study indicated that the ornithine and proline together along with methylglyoxal contribute towards the enhancement of 2AP under salt stress.

Hepatoprotective Potential of Lycopene in a Rat Model of Cisplatin-Induced Damage: Involvement of Oxidative Cell Damage and Glutathione Metabolism

Application of cisplatin for the treatment of various solid tumors is known to cause liver damage, through an increase in lipid peroxidation and reactive oxygen species production. Lycopene is a powerful antioxidant agent capable of preventing the cells damage, the formation of stronger intercellular bonds and faster cellular metabolism. This study aims to estimate the potential of lycopene in preventing cisplatin induced liver tissue damage by studying the levels of several biochemical parameters (arginase, aminotransferases, alkaline phosphatase, gamma-glutamyl transpeptidase activity, total protein and albumin concentration) reflecting liver function and a panel of liver tissue biomarkers (xanthine oxidase, reduced glutathione, malondialdehyde, protein carbonylated concentration and diamino oxidase activity). These parameters would be studied in male Wistar rats treated with either cisplatin alone or with cisplatin and lycopene. Additionally, microscopic analysis of liver tissue would be conducted as well. Application of the combination of lycopene and cisplatin significantly prevented the disturbance in all here-studied biomarkers of liver tissue damage. Morphological liver tissue alterations followed the changes in hepatic biochemical status. Our results suggest that lycopene could act as a protective agent in cisplatin-induced liver damage in rats.

Roflumilast, a type of phosphodiesterase 4 inhibitor, can reduce intestinal injury caused by sepsis.

Sepsis is a systemic inflammatory response syndrome caused by infection, which has a complex mechanism. The gastrointestinal tract is commonly the first organ affected by sepsis, but intestinal disease itself can also induce sepsis. Roflumilast has been found to exert anti-inflammatory effects and, thus, the present study sought to examine its effect on intestinal damage caused by sepsis. In vivo studies were conducted using cecal ligation and puncture rat models, and in vitro experiments were performed using IEC-6 cells. The intestinal cells were first induced with lipopolysaccharide and the induced cells were then treated with roflumilast to evaluate its effects on phosphodiesterase (PDE)4 expression, intestinal function indices, release of inflammatory factors and cell apoptosis. The expression level of PDE4 in the small intestinal tissue of septic rats was found to be significantly higher compared with that in the normal group, suggesting that PDE4 may play a key role in intestinal injury caused by sepsis. It was found that roflumilast reduced PDE4 expression, as well as the levels of intestinal function indices, including lactate dehydrogenase, diamino oxidase and intestinal fatty acid-binding protein, in intestinal cells. Moreover, roflumilast reduced cellular damage, the release of inflammatory factors and apoptosis. In summary, the findings of the present study indicated that roflumilast can relieve the inflammation and apoptosis of intestinal cells caused by sepsis and can promote their functional recovery. These findings may promote the expansion of the clinical application of roflumilast in the future.

Immune-Mediated Mechanisms in Cofactor-Dependent Food Allergy and Anaphylaxis: Effect of Cofactors in Basophils and Mast Cells.

Cofactors may explain why in some cases food ingestion leads to anaphylaxis while in others elicits a milder reaction or tolerance. With cofactors, reactions become more severe and/or have a lower allergen threshold. Cofactors are present in up to 58% of food anaphylaxis (FAn). Exercise, NSAIDs, and alcohol are the most frequently described, although the underlying mechanisms are poorly known. Several hypotheses have suggested the influence of these cofactors on basophils and mast cells (MCs). Exercise has been suggested to enhance MC activation by increasing plasma osmolarity, redistributing blood flow, and activating adenosine and eicosanoid metabolism. NSAIDs’ cofactor effect has been related with cyclooxygenase inhibition and therefore, prostaglandin E2 (PGE2) production. Indeed, overexpression of adenosine receptor 3 (A3) gene has been described in NSAID-dependent FAn; A3 activation potentiates FcϵRI-induced MC degranulation. Finally, alcohol has been related with an increase of histamine levels by inhibition of diamino oxidase (DAO) and also with and increase of extracellular adenosine by inhibition of its uptake. However, most of these mechanisms have limited evidence, and further studies are urgently needed. In conclusion, the study of the immune-related mechanisms involved in food allergic reactions enhanced by cofactors is of the utmost interest. This knowledge will help to design both tailored treatments and prophylactic strategies that, nowadays, are non-existent.

Involvement of Polyamine Metabolism in the Response of Medicago truncatula Genotypes to Salt Stress.

Salinity constitutes one of the most important causes leading to severe reduction in plant yield. Several reports correlate the accumulation of polyamines in plants with tolerance to abiotic stress cues. The present study examined three Medicago truncatula genotypes with differing sensitivities to salinity (TN1.11, tolerant; Jemalong A17, moderately sensitive; TN6.18, sensitive), with the aim of examining the genotype-specific involvement of the polyamine metabolic pathway in plant response to salinity. The study was carried out with leaves harvested 48 h after watering plants with 200 mM NaCl. A comprehensive profile of free polyamines was determined using high performance liquid chromatography. All genotypes showed spermidine and spermine as the most abundant polyamines under control conditions. In salinity conditions, spermine levels increased at the expense of putrescine and spermidine, indicating a drift of polyamine metabolism towards the synthesis of increasing polycationic forms as a stress response. The increasing balance between high and low polycationic forms was clearly diminished in the salt-sensitive genotype TN6.18, showing a clear correlation with its sensitive phenotype. The polyamine metabolic profile was then supported by molecular evidence through the examination of polyamine metabolism transcript levels by RT-qPCR. General suppression of genes that are involved upstream in the PA biosynthetic pathway was determined. Contrarily, an induction in the expression of genes involved in the biosynthesis of spermine and spermidine was observed, in agreement with the metabolic analysis. A significant induction in diamino oxidase expression, involved in the catabolism of putrescine, was specifically found in the sensitive genotype ΤΝ6.18, indicating a distinct metabolic response to stress. Present findings highlight the involvement of polyamines in the defense response of Medicago genotypes showing sensitivity to salt stress.

Lathyrus sativus diamine oxidase reduces Clostridium difficile toxin A-induced toxicity in Caco-2 cells by rescuing RhoA-GTPase and inhibiting pp38-MAPK/NF-κB/HIF-1α activation.

Clostridium difficile toxin A (TcdA) impairs the intestinal epithelial barrier, increasing the mucosa permeability and triggering a robust inflammatory response. Lathyrus sativus diamino oxidase (LSAO) is a nutraceutical compound successfully used in various gastrointestinal dysfunctions. Here, we evaluated the LSAO (0.004-0.4 μM) ability to counter TcdA-induced (30 ng/mL) toxicity and damage in Caco-2 cells, investigating its possible mechanism of action. LSAO has improved the transepithelial electrical resistance (TEER) score and increased cell viability in TcdA-treated cells, significantly rescuing the protein expression of Ras homolog family members, A-GTPase (RhoA-GTPase), occludin, and zonula occludens-1 (ZO-1). LSAO has also exhibited an anti-apoptotic effect by inhibiting the TcdA-induced expression of Bcl-2-associated X protein (Bax), p50 nuclear factor-kappa-B (p50), p65nuclear factor-kappa-B (p65), and hypoxia-inducible transcription factor-1 alpha (HIF-1α), and the release of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and vascular endothelial growth factor (VEGF) in the cell milieu. Our data showed that LSAO exerts a protective effect on TcdA-induced toxicity in Caco-2 cells, placing itself as an interesting nutraceutical to supplement the current treatment of the Clostridium difficile infections.

Smartphone-interrogated test supports for the enzymatic determination of putrescine and cadaverine in food.

Diamino-oxidase (DAO), horseradish peroxidase (HRP), and tetramethylbenzidine (TMB) have been immobilized into cellulose to obtain circular cellulose test supports (CCTSs) for the determination of cadaverine (Cad) and putrescine (Put). During the enzymatic reaction, TMB is oxidized and a blue spot is obtained. This color (RGB coordinates) is measured with a smartphone and a commercial application. The highest sensitivity is provided by the component R and a linear response is observed for low biogenic amine (BA) concentrations, but a second-order polynomial response better fits the experimental results for a wider concentration range. This has been successfully explained with a model developed to explain the RGB values obtained in this type of analytical system. Optimization studies enable CCTSs to be obtained for Put and Cad determination, which could be used (kept at 4°C) for at least 45days if a stabilizer (StabilCoat™ or StabilGuard™) is added during its synthesis. In these conditions, the R coordinate follows the model up to at least 4 × 10-4M Put and/or Cad (both analytes give the same response). The method permits the Put and Cad determination from 5 × 10-5M up to 4 × 10-4M (RSD = 3%, n = 3). The CCTSs have been applied to Put + Cad determination in a tuna sample without any interference by other biogenic amines. The concentration found statistically agrees with that obtained using a HPLC-MS-validated method. Graphical abstract.

Water availability influences morphology, mycorrhizal associations, PSII efficiency and polyamine metabolism at early growth phase of Scots pine seedlings

Scots pine (Pinus sylvestris L.) is adapted to various soil types with diverse water availabilities. However, Scots pine seedlings are vulnerable to abiotic stress during the early growth, when they may be exposed to both dry and wet conditions. Here, we focused on the above and below ground coping strategies of Scots pine seedlings under controlled wet, optimal and dry soil conditions by investigating morphological traits including seedling biomass, number of root tips, proportion of mycorrhizal root tips and brown needles. In addition, we studied metabolic and physiological responses including gene expression involved in biosynthesis and catabolism of polyamines (PA), PSII efficiency and the expression of the catalase (CAT) late-embryogenesis abundant protein (LEA), pyruvate decarboxylase (PDC), glutamate-cysteine ligase (GCL) and glutathione synthetase (GS) genes. We found that seedlings invested in shoots by maintaining stable shoot water content and high PSII efficiency under drought stress. Free and soluble conjugated putrescine (Put) accumulated in needles under drought stress, suggesting the role of Put in protection of photosynthesizing tissues. However, the expression of the PA biosynthesis genes, arginine decarboxylase (ADC), spermidine synthase (SPDS) and thermospermine synthase (ACL5) was not affected under drought stress whereas catabolizing genes diamino oxidase (DAO) and polyamine oxidase (PAO) were down-regulated in shoots. The morphology of the roots was affected by peat water content. Furthermore, both drought stress and water excess restricted the seedling ability to sustain a symbiotic relationship. The consistent pattern of endogenous PAs seems to be advantageous to the Scots pine seedlings also under stress conditions.

Protective effect of glutamine on intestinal injury and bacterial community in rats exposed to hypobaric hypoxia environment.

To investigate the protective effect of glutamine (Gln) on intestinal injury and the bacterial community in rats exposed to hypobaric hypoxia environment. Sprague-Dawley rats were divided into control, hypobaric hypoxia (HH), and hypobaric hypoxia + Gln (5.0 g/kg BW·d) (HG) groups. On the first 3 d, all rats were placed in a normal environment. After the third day, the HH and HG groups were transferred into a hypobaric chamber at a simulated elevation of 7000 m for 5 d. The rats in the HG group were given Gln by gavage daily for 8 d. The rats in the control and HH groups were treated with the same volume of saline. The intestinal morphology, serum levels of malondialdehyde (MDA), superoxide dismutase (SOD), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interferon-gamma (IFN-γ) and diamino oxidase (DAO) were examined. We also evaluated the expression levels of occludin, toll-like receptor 4 (TLR4), nuclear factor-κB p65 (NF-κB p65) and myeloid differentiation factor 88 (MyD88), and examined the bacterial community in caecal contents. Hypobaric hypoxia induced the enlargement of the heart, liver, lung and kidney, and caused spleen atrophy. Intestinal villi damage was also observed in the HH group. Supplementation with Gln significantly alleviated hypobaric-induced damage to main organs including the intestine, increased serum SOD (1.14 ± 0.03 vs 0.88 ± 0.04, P < 0.05) and MDA (8.35 ± 1.60, P < 0.01) levels and decreased serum IL-6 (1172.13±30.49 vs 1407.05 ± 34.36, P < 0.05), TNF-α (77.46 ± 0.78 vs 123.70 ± 3.03, P < 0.001), IFN-γ (1355.42 ± 72.80 vs 1830.16 ± 42.07, P < 0.01) and DAO (629.30 ± 9.15 vs 524.10 ± 13.34, P < 0.001) levels. Moreover, Gln significantly increased occludin (0.72 ± 0.05 vs 0.09 ± 0.01, P < 0.001), TLR4 (0.15 ± 0.05 vs 0.30 ±0.09, P < 0.05), MyD88 (0.32 ± 0.08 vs 0.71 ± 0.06, P < 0.01), and NF-κB p65 (0.16 ± 0.04 vs 0.44 ± 0.03, P < 0.01) expression levels and improved the intestinal bacterial community. Gln treatment protects from intestinal injury and regulates the gut flora imbalance in hypoxia environment. These effects may be related to the TLR4/MyD88/NF-κB signaling pathway.

Effect of vitamin e supplementation on intestinal barrier function in rats exposed to high altitude hypoxia environment.

The study was conducted to investigate the role of vitamin E in the high altitude hypoxia-induced damage to the intestinal barrier in rats. Sprague-Dawley rats were divided into control (Control), high altitude hypoxia (HH), and high altitude hypoxia+vitamin E (250 mg/kg BW*d) (HV) groups. After the third day, the HH and HV groups were placed in a hypobaric chamber at a stimulated elevation of 7000 m for 5 days. The rats in the HV group were given vitamin E by gavage daily for 8 days. The other rats were given equal volume saline. The results showed that high altitude hypoxia caused the enlargement of heart, liver, lung and kidney, and intestinal villi damage. Supplementation with vitamin E significantly alleviated hypoxia-caused damage to the main organs including intestine, increased the serum superoxide dismutase (SOD) (p< 0.05), diamino oxidase (DAO) (p< 0.01) levels, and decreased the serum levels of interleukin-2 (IL-2) (p< 0.01), interleukin-4 (IL-4) (p<0.001), interferon-gamma (IFN-γ) (p<0.01) and malondialdehyde (MDA) (p<0.001), and decreased the serum erythropoietin (EPO) activity (p<0.05). Administration of vitamin E significantly increased the S-IgA (p<0.001) in ileum and significantly improved the expression levels of occludin and IκBα, and decreased the expression levels of hypoxia-inducible factor 1 alpha and 2 alpha (HIF-1α and HIF-2α), Toll-like receptors (TLR4), P-IκBα and nuclear factor-κB p65(NF-κB P65) in ileum compared to the HH group. This study suggested that vitamin E protectis from intestinal injury caused by high altitude hypoxia environment. These effects may be related to the HIF and TLR4/NF-κB signaling pathway.

Attenuating effects of omega-3 fatty acids (Omegaven) on irradiation-induced intestinal injury in mice

Gastrointestinal injury is a major cause of death following exposure to high levels of irradiation, and no effective treatments are currently available. In this study, we examined the effect of omega-3 fatty acids (Omegaven) on intestinal injury of BALB/c mice induced by irradiation. Intravenously administered 3days prior to irradiation for 7 consecutive days, Omegaven was shown to improve survival, intestinal morphology including villous height, crypt height and mucosal thickness and the intestinal proliferation compared with saline control. Omegaven also normalized the levels of circulating tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6), attenuated the increase of diamino oxidase (DAO) activity and malondialdehyde (MDA) level and recovered the decrease of superoxide dismutase (SOD) activity. Meanwhile, Omegaven attenuated the myelosuppression caused by irradiation. In conclusion, our results suggest that Omegaven enhanced the survival of irradiated mice and minimized the effects of radiation on gastrointestinal injury.

A randomized doubled blinded trial of treatment with diamino-oxidase (DAO) in patients with migraine and deficit of enzyme'/INS;s activity

Background: Histamine has been considerate as a chemical mediator of migraine. The degradation is done in two different pathways. One of the enzymes that allow this process is the diamino-oxidase (DAO).

Competitive inhibition of copper amine oxidases by vitamin B hydrochloride in chickpea

A B S T R A C T Copper amine oxidases (CAOs) catalyse the oxidative de-amination of biogenic amines which are ubiquitous compounds essential for cell growth and proliferation. The enzymes are homodimers containing both topaquinone and a Cu(II) ions as cofactors at the active site of each subunit. After extraction and purification of chickpea (cicer arietinum) amine oxidase by chromatoghraphy, Km and Vmax of the enzyme were determined to be 3.3 mM and 0.95 mmol/min/mg, respectively, using a Lineweaver-Burk plot. In this study, the interaction of chickpea diamino oxidase with vitamin B hydrochloride was studied. Vitamin B hydrochloride (Thiamin) by Ki=8 mM acted as competitive inhibitor of the enzyme.

Histamine intolerance as a cause of chronic digestive complaints in pediatric patients

histamine intolerance (HI) is a poorly described disease in gastroenterology that may present with predominant digestive complaints. The goals of this study include a report of two cases diagnosed in a pediatric gastroenterology clinic. observational, retrospective study of patients diagnosed with HI from September 2010 to December 2011 at the pediatric gastroenterology clinic of a tertiary hospital.They were deemed to have a diagnosis of HI in the presence of 2 or more characteristic digestive complaints, decreased diamino oxidase (DAO) levels and/or response to a low histamine diet with negative IgE-mediated food allergy tests. sixteen patients were diagnosed. Males predominated versus females (11/5). Mean age at symptom onset was 4 years (6 months vs. 13 years and 6 months) and mean age at diagnosis was 6 years and 6 months (17 months vs. 13 years and 11 months), with an interval of 2 years and 1 month between symptom onset and diagnosis (5 months vs. 4 years). Predominant symptoms included diffuse abdominal pain (16/16), intermittent diarrhea (10/16), headache (5/16), intermittent vomiting (4/16), and skin rash (2/16). The diagnosis was established by measuring plasma diamino oxidase levels, which were below 10 kU/L (normal > 10 kU/L) in 14 cases, and symptom clearance on initiating a low histamine diet. In two patients DAO levels were above 10 kU/L but responded to diet. Treatment was based on a diet low in histamine-contaning food, and antihistamines H1 y H2 had to be added for two cases. histamine intolerance is a little known disease with a potentially relevant incidence. Predominant complaints include diffuse abdominal pain, diarrhea, headache, and chronic intermittent vomiting. Its diagnosis is based on clinical suspicion, plasma DAO measurement, and response to a low histamine diet. Management with the latter provides immediate improvement.

Reactivity of liver monoamine oxidase in the seal Phoca hispida ladogensis

The goal of this work consisted in substrate and inhibitor specificity of liver monoamine oxidase (MAO) of the freshwater Ladoga subspecies of the ringed seal Phoca hispida ladogensis. The studied enzyme has been found to have the large substrate specificity by deaminating, apart from eight classic substrates of the terrestrial mammalian MAO, also histamine, the substrate of diamino oxidase. It has been revealed that the studied enzyme realizes wide substrate specificity by deaminating, apart from eight classic MAO substrates of terrestrial mammals, also histamine, the substrate of diamino oxidase. The deamination rates of benzylamine, β-phenylethylamine, and N-methylhistamine are found to be almost by one order higher than the deamination rates of serotonin and noradrenaline. The seal liver MAO did not deaminate putrescine and cadaverine and was insensitive to 10−2 M semicarbaside. There were calculated bimolecular rate constants of interaction of inhibitors: chlorgyline, deprenyl, berberine, sanguinarine, chelidonine, and four derivatives of acridine with the enzyme at deamination of nine substrates. By the method of substrate-inhibitor analysis we have shown heterogeneity of the enzyme, i.e., the presence in the seal liver of at least of two different MAO.