Changes in photosynthetic pigments, osmolytes and antioxidants of Indian mustard by drought and exogenous polyamines.

A pot experiment was performed as factorial based on randomized complete block design with three replications, to assess the effects of 1 mM spermidine (SPD) and 1 mM putrescine (PUT) on Indian mustard (Brassica Juncea L.) under different levels of watering (100, 75, 50 and 25% of field capacity). Chlorophyll a and b contents decreased, but the ratio of Chl a/b and carotenoid content increased with decreasing water supply. Foliar sprays of polyamines improved chlorophylls a and b and carotenoid contents, while the ratio of Chl a/b was reduced by these growth regulators. Relative water content, glycine betaine, proteins and soluble sugars contents were increased, but proline content was decreased by exogenous polyamines under limited water supply. Antioxidant enzyme (POX, CAT, SOD and APX) activities were enhanced by drought stress and polyamine treatments. This resulted in lower electrolyte leakage and lipid peroxidation (less MDA) under stressful conditions. The present results indicate that exogenous polyamines such as putrescine and spermidine can alleviate some of the deleterious impacts of water limitation on Indian mustard.

Putrescine supplementation during in vitro maturation of aged mouse oocytes improves the quality of blastocysts.

Mouse ovaries exhibit a peri-ovulatory rise of ornithine decarboxylase and its product putrescine concurrent with oocyte maturation. Older mice exhibit a deficiency of both the enzyme and putrescine. Peri-ovulatory putrescine supplementation in drinking water increases ovarian putrescine levels, reduces embryo resorption and increases live pups in older mice. However, it is unknown if putrescine acts in the ovaries to improve oocyte maturation. This study examined the impact of putrescine supplementation during oocyte in vitro maturation (IVM) on the developmental potential of aged oocytes. Cumulus-oocyte complexes from 9-12-month-old C57BL/6 mice were subjected to IVM with or without 0.5mM putrescine, followed by in vitro fertilisation and culture to the blastocyst stage. Putrescine supplementation during IVM did not influence the proportion of oocyte maturation, fertilisation or blastocyst formation, but significantly increased blastocyst cell numbers (44.5±1.9, compared with 36.5±1.9 for control; P=0.003). The putrescine group also had a significantly higher proportion of blastocysts with top-grade morphology (42.9%, compared with 26.1% for control; P=0.041) and a greater proportion with octamer-binding transcription factor 4 (OCT4)-positive inner cell mass (38.3%, compared with 19.8% for control; P=0.005). Therefore, putrescine supplementation during IVM improves egg quality of aged mice, providing proof of principle for possible application in human IVM procedures for older infertile women.

Acute Putrescine Supplementation with Schwann Cell Implantation Improves Sensory and Serotonergic Axon Growth and Functional Recovery in Spinal Cord Injured Rats.

Schwann cell (SC) transplantation exhibits significant potential for spinal cord injury (SCI) repair and its use as a therapeutic modality has now progressed to clinical trials for subacute and chronic human SCI. Although SC implants provide a receptive environment for axonal regrowth and support functional recovery in a number of experimental SCI models, axonal regeneration is largely limited to local systems and the behavioral improvements are modest without additional combinatory approaches. In the current study we investigated whether the concurrent delivery of the polyamine putrescine, started either 30 min or 1 week after SCI, could enhance the efficacy of SCs when implanted subacutely (1 week after injury) into the contused rat spinal cord. Polyamines are ubiquitous organic cations that play an important role in the regulation of the cell cycle, cell division, cytoskeletal organization, and cell differentiation. We show that the combination of putrescine with SCs provides a significant increase in implant size, an enhancement in axonal (sensory and serotonergic) sparing and/or growth, and improved open field locomotion after SCI, as compared to SC implantation alone. These findings demonstrate that polyamine supplementation can augment the effectiveness of SCs when used as a therapeutic approach for subacute SCI repair.

Resembling breast milk: influence of polyamine-supplemented formula on neonatal BALB/cOlaHsd mouse microbiota.

Infant microbiota is influenced by numerous factors, such as delivery mode, environment, prematurity and diet (breast milk or formula). In addition to its nutritional value, breast milk contains bioactive substances that drive microbial colonisation and support immune system development, which are usually not present in infant formulas. Among these substances, polyamines have been described to be essential for intestinal and immune functions in newborns. However, their effect on the establishment of microbiota remains unclear. Therefore, the aim of the present study was to ascertain whether an infant formula supplemented with polyamines has an impact on microbial colonisation by modifying it to resemble that in breast-fed neonatal BALB/c mice. In a 4 d intervention, a total of sixty pups (14 d old) were randomly assigned to the following groups: (1) breast-fed group; (2) non-enriched infant formula-fed group; (3) three different groups fed an infant formula enriched with increasing concentrations of polyamines (mixture of putrescine, spermidine and spermine), following the proportions found in human milk. Microbial composition in the contents of the oral cavity, stomach and small and large intestines was analysed by quantitative PCR targeted at fourteen bacterial genera and species. Significantly different (P< 0·05) microbial colonisation patterns were observed in the entire gastrointestinal tract of the breast-fed and formula-fed mice. In addition, our findings demonstrate that supplementation of polyamines regulates the amounts of total bacteria, Akkermansia muciniphila, Lactobacillus, Bifidobacterium, Bacteroides-Prevotella and Clostridium groups to levels found in the breast-fed group. Such an effect requires further investigation in human infants, as supplementation of an infant formula with polyamines might contribute to healthy gastrointestinal tract development.

Exogenous application of putrescine at pre-anthesis enhances the thermotolerance of wheat (Triticum aestivum L.).

Antioxidant enzymes, besides being involved in various developmental processes, are known to be important for environmental stress tolerance in plants. In this study, the effect of treatment of 2.5 mM putrescine (Put), heat stress (HS -42 degrees C for 2 h) and their combination on the expression and activity of antioxidant enzymes was studied at pre-anthesis in the leaves of two wheat (Triticum aestivum L.) cultivars--HDR77 (thermotolerant) and HD2329 (thermosusceptible). We observed that 2.5 mM Put before HS significantly enhanced the transcript levels of superoxide dismutase (SOD), catalase (CAT), cytoplasmic and peroxisomal ascorbate peroxidase (cAPX, pAPX) in both the cultivars. However, the activities of antioxidant enzymes (SOD, CAT, APX and GR), as well as accumulation of antioxidants (ascorbic acid and total thiol content) were higher in HDR77 than in HD2329 in response to the treatment 2.5 mM Put + HS. No significant change was observed in the proline accumulation in response to HS and combined treatment of 2.5 mM Put + HS. A decrease in the H2O2 accumulation, lipid peroxidation and increase in cell membrane stability (CMS) were observed in response to 2.5 mM Put + HS treatment, as compared to HS treatment alone in both the cultivars; HDR77 was, however, more responsive to 2.5 mM Put + HS treatment. Put (2.5 mM) treatment at pre-anthesis thus modulated the defense mechanism responsible for the thermotolerance capacity of wheat under the heat stress. Elicitors like Put, therefore, need to be further studied for temporarily manipulating the thermotolerance capacity of wheat grown under the field conditions in view of the impending global climate change.

Reversal of difluoromethylornithine effects by the administration of putrescine in rats.

OBJECTIVE: To assess the reversal of Di-fluoromethyl ornithine (DFMO) effects by administration of putrescine on thyroid glands in rats. METHODS: The study was conducted on female rats weighing 248 to 320 grams at Quaid-e-Azam University, Islamabad in November end 2006. They were divided into three groups namely control group I treated with normal saline, DFMO treated group II at a dose of 50 mg/rat and DFMO and Putrescine group III received a combination of 50 mg/rat of DFMO and 150 microg of Putrescine, subcutaneously for five consecutive days. On sixth day, blood was collected by cardiac puncture and radioimmunoassay was performed to measure Serum T3, T4 and TSH levels in all groups. RESULTS: In group II there was a fall in T3, T4 concentration with significant rise in TSH concentration as compared to the control group. The combined administration of Putrescine and DFMO resulted in a rise in serum T3 and T4 with negligible fall in TSH. CONCLUSION: DFMO induced hypothyroidism was reversed by the administration of Putrescine. It is thus concluded that hormone mediated response in thyroid tissue can be altered by altering ODC responsiveness of target tissue of female rats.

Central L-ornithine, but not polyamines, induces a hypnotic effect in neonatal chicks under acute stress.

To clarify whether L-ornithine and/or its metabolite involves sedative and hypnotic effects under social separation stress, the effects of intracerebroventricular (i.c.v.) injection of L-ornithine and polyamines (putrescine, spermidine and spermine) were compared in chicks. Birds were injected i.c.v. with 0.5 mumol of L-ornithine, putrescine, spermidine, spermine or saline (control). After injection, chicks were immediately separated from the flock and monitored for the number of distress vocalizations and various postures. L-Ornithine greatly attenuated the stress response and caused sedative and hypnotic effects. Among the polyamines, only putrescine attenuated distress vocalizations but did not induce sleep. In conclusion, the sedative and hypnotic effect of L-ornithine was mainly induced by L-ornithine itself, while the polyamines contributed to the sedative, but not hypnotic, effect under social separation stress.

A putrescine-anthracene conjugate: a paradigm for selective drug delivery.

Increased polyamine concentrations play an important role in the development of cancer at all stages, from initiation through to maintenance of the transformed phenotype. One way cancer cells accumulate increased concentrations of polyamines is by increased uptake of preformed polyamines via their PTS (polyamine transport system). The PTS is promiscuous and will transport a range of polyamine-based molecules. Therefore it may be that cytotoxic drugs could be attached to polyamine vectors and targeted selectively to cancer cells by utilizing the PTS. The aim of the present study was to investigate the potential of Ant 4, a putrescine-anthracene conjugate, to target cytotoxic agents to human cancer cells as a paradigm for a novel method of selective drug delivery. Ant 4 induced cytotoxicity after only 24 h exposure. Apoptosis was the predominant type of cell death, with mechanistic studies revealing that oxidative stress and DNA damage may have a part to play. For the first time, uptake of Ant 4 via the PTS was demonstrated both directly and indirectly in human cell lines. In addition, Ant 4 significantly reduced putrescine uptake, demonstrating that this conjugate not only used the PTS, but also could successfully compete with its native polyamine for uptake. However, the most interesting finding was the intracellular depletion of the polyamine pools, providing an additional mode of toxicity for Ant 4 and the possibility that this molecule may act as a 'double-edged sword': preventing cell growth by delivery of the toxic moiety and by depletion of intracellular polyamine content.

Dietary Polyamines Intake and Risk of Colorectal Cancer: A Case-Control Study.

Polyamines (including putrescine, spermidine, and spermine) are small, cationic molecules that are necessary for cell proliferation and differentiation. Few studies have examined the association of dietary polyamines intake with colorectal cancer risk. The aim of this study was to evaluate total polyamines, putrescine, spermidine, and spermine intake in relation to colorectal cancer risk in China. In total, 2502 colorectal cancer cases and 2538 age-(5-year interval) and sex-matched controls were recruited from July 2010 to April 2019. Odds ratios (ORs) and 95% confidence intervals (CI) were calculated by multivariable unconditional logistic regression after adjustment for various potential confounding factors. Higher intake of total polyamine, putrescine and spermidine was significantly associated with reduced risk of colorectal cancer. The adjusted ORs for the highest compared with the lowest quartile of intake were 0.60 (95% CI 0.50, 0.72; Ptrend < 0.001) for total polyamines, 0.35 (95% CI 0.29, 0.43; Ptrend < 0.001) for putrescine and 0.79 (95% CI 0.66, 0.95; Ptrend = 0.001) for spermidine, respectively. However, higher intake of spermine was associated with increased risk of colorectal cancer, with an adjusted OR of 1.58 (95% CI 1.29, 1.93; Ptrend < 0.001). This data indicate that higher intake of total polyamines, putrescine and spermidine, as well as lower intake of spermine, is associated with a decreased risk of colorectal cancer.

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

Objective evidence for the role of inhibition of collagen cross-linking in human scar using a nontoxic topical inhibitor, 1,4-diaminobutane (1,4 DAB), in patients with scars at risk for hypertrophic scar formation is presented. The authors used a concentration of 1,4 DAB of 0.8% (weight/volume) in a cream base similar to Glaxal Base. Application was once per day at night. The control was treated with cream base alone. In treatment phase studies at 2 months, tissue biopsies were performed and used to determine a therapeutic effect biochemically in paired scars harvested chosen with typical hypertrophic scars at two major treatment centers. Tissue transglutaminase activity revealed a significant reduction of the ε-(γ-glutamyl)lysine cross-links in the treated scars: 7.96 ± 1.51 pmol/µmol amino acid versus 14.78 ± 3.52 pmol/µmol amino acid. A subset of paired scars (n = 15) was also analyzed for soluble procollagen type III amino propeptide. The effect was a significant increase in procollagen type III amino propeptide in the scars treated with 1,4 DAB compared with sham-treated scars: 47.75 ± 4.6 µg/mg wet weight versus 39.08 ± 6.02 µg/mg wet weight, respectively. Levels of tissue 1,4 DAB was found to be twice as high in the presence of the active cream versus in the tissue of the control group. In subsequent prophylaxis studies, the authors treated 44 breast reduction patients prospectively with active cream to one or the other side in a double-blind randomized fashion. Hardness (in grams) measured using a Rex Durometer at 6 and 12 weeks postoperatively along with photographs were analyzed. The mean value ± SD of 24.98 ± 1.2 g on the active side versus 31.76 ± 1.1 g on the sham side was significantly different (p < 0.05). The patient scale scores of the Patient and Observer Scar Assessment Scale were also requested by survey in a responding 27-patient subgroup at a minimum 1 year postoperatively, and the differences between the two sides were found to be statistically significant, where the mean on the active side was 14.07 ± 1.34 and the mean on the sham side was 21.41 ± 1 (p < 0.05). The results are evidence to support the use of this agent in prevention of hypertrophic scars. CLINICAL QUESTION/LEVEL OF EVIDENCE:: Therapeutic, II.

Degradable PEG-folate coated poly(DMAEA-co-BA)phosphazene-based polyplexes exhibit receptor-specific gene expression.

A new cationic biodegradable polyphosphazene was developed, bearing both pendant primary and tertiary amine side groups, poly(2-dimethylaminoethylamine-co-diaminobutane)phosphazene (poly(DMAEA-co-BA)phosphazene). PEG and PEG-folate were coupled to polyplexes based on this poly(DMAEA-co-BA)phosphazene, leading to small (size 100 and 120nm, respectively) and almost neutral particles. In vitro tissue culture experiments showed a low cytotoxicity of both uncoated and coated polyplexes. However, the PEG coated polyplexes showed a 2-fold lower transfection activity in OVCAR 3 cells as compared to the uncoated polyplexes. On the other hand, the PEG-folate coated polyplexes had a 3-fold higher transfection than the PEGylated polyplexes. When free folate was added to the transfection medium, only the transfection activity of the targeted polyplexes was reduced, indicating internalization of the targeted PEG polyplexes via the folate receptor. Confocal laser scanning microscopy confirmed a lower binding and uptake of the PEGylated polyplexes by OVCAR-3 cells when compared to uncoated and folate-PEGylated polyplexes. While uncoated polyplexes induced aggregation of erythrocytes at polymer concentrations of 0.09microg/mL, the PEGylated systems could be incubated at ten times higher concentration before aggregation occurred indicating excellent shielding of the surface charge of the polyplexes by grafting of PEG. In conclusion, the targeted delivery of poly(DMAEA-co-BA)phosphazene bases polyplexes and their improved compatibility with erythrocytes makes them interesting for in vivo applications.

Improvement of intestinal absorption of water-soluble macromolecules by various polyamines: intestinal mucosal toxicity and absorption-enhancing mechanism of spermine.

The absorption-enhancing effects of three different polyamines, spermine (SPM), spermidine (SPD) and putrescine (PUT) on the intestinal absorption of water-soluble macromolecules were examined in rats. Fluorescein isothiocyanate-labeled dextrans (FDs) with different average molecular weights were chosen as models of water-soluble macromolecules and intestinal absorption of FDs with or without these polyamines was examined by an in situ closed loop method. The intestinal absorption of fluorescein isothiocyanate-labeled dextran with an average molecular weight of 4400 (FD4) was relatively low in the absence of these polyamines. However, its absorption was improved in the presence of 5-10mM SPM and 10mM SPD in the jejunum and 10mM SPM in the colon, while 10mM PUT had almost no absorption-enhancing effect on the intestinal absorption of FD4. Overall, the enhancing effects of these polyamines were greater in the jejunal membranes than in the colonic membranes. The absorption-enhancing effect of SPM decreased as the molecular weights of FDs increased. The intestinal membrane toxicity of 10mM SPM was evaluated by measuring the amount of protein and activity of lactate dehydrogenase (LDH) released from the intestinal epithelial cells. We also observed the morphological changes of intestinal mucosa in the presence or absence of SPM. The results indicated that the amount of protein and LDH was not changed in the presence of 10mM SPM, although we observed a significant increase in these biological markers in the presence of 3% Triton X-100, as a positive control. Furthermore, we found no significant change in the intestinal membrane with 10mM SPM by the morphological observation. These findings suggested that 10mM SPM did not cause any significant membrane damage to the intestinal epithelium. To investigate the absorption-enhancing mechanism of SPM, the transepithelial electrical resistance (TEER) of the rat jejunal membranes was studied by using a diffusion chamber method. SPM decreased the TEER values in a concentration dependent manner and 10mM SPM had almost the same effect to decrease the TEER value compared with 10mM EDTA as a positive control. These findings suggest that SPM may loosen the tight junction of the epithelium, thereby increasing the intestinal absorption of drugs via a paracellular route. In summary, polyamines, especially SPM would be one of the suitable absorption enhancers with high effectiveness and low intestinal membrane toxicity.

An altered gene expression profile in tyramine-exposed intestinal cell cultures supports the genotoxicity of this biogenic amine at dietary concentrations.

Tyramine, histamine and putrescine are the most commonly detected and most abundant biogenic amines (BA) in food. The consumption of food with high concentrations of these BA is discouraged by the main food safety agencies, but legal limits have only been set for histamine. The present work reports a transcriptomic investigation of the oncogenic potential of the above-mentioned BA, as assessed in the HT29 human intestinal epithelial cell line. Tyramine had a greater effect on the expression of genes involved in tumorigenesis than did histamine or putrescine. Since some of the genes that showed altered expression in tyramine-exposed cells are involved in DNA damage and repair, the effect of this BA on the expression of other genes involved in the DNA damage response was investigated. The results suggest that tyramine might be genotoxic for intestinal cells at concentrations easily found in BA-rich food. Moreover, a role in promoting intestinal cancer cannot be excluded.

A sequential injection analysis/chemiluminescent plant tissue-based biosensor system for the determination of diamine.

In this paper, a new chemiluminescent plant tissue-based biosensor for diamine detection was presented by employing sequential injection analysis (SIA), which facilitates precise fluidic handling and lower consumption of sample and reagents. Pea-seedling tissue acted as the molecular recognition element and was packed in a mini-PTFE column and further incorporated in the SIA system. The analysis of diamines, such as putrescine and cadaverine, is based on an enzymatic conversion which takes place in the plant tissue column to produce hydrogen peroxide. The formed hydrogen peroxide was detected by a chemiluminescence reaction involving luminol and Co(2+). Under the optimal conditions, the linear calibration graphs were obtained within 0.2-80 microM (putrescine) and 0.5-100 microM (cadaverine). The detection limits of 0.03 and 0.06 microM were achieved for putrescine and cadaverine, respectively, along with the relative standard deviations of 2.14% and 3.08% (n=11) and a sampling frequency of 40 h(-1). The present biosensor has been used for the analysis of diamine in fish samples with an acceptable accuracy.

Development of a polyamine database for assessing dietary intake.

Reducing the concentration of polyamines (spermine, spermidine, and putrescine) in the body pool may slow the cancer process. Because dietary spermine, spermidine, and putrescine contribute to the body pool of polyamines, quantifying them in the diet is important. Limited information about polyamine content of food is available, especially for diets in the United States. This brief report describes the development of a polyamine database linked to the Fred Hutchinson Cancer Center food frequency questionnaire (FFQ). Values for spermine, spermidine, and putrescine were calculated and reported per serving size (nmol/serving). Of the foods from the database that were evaluated, fresh and frozen corn contain the highest levels of putrescine (560,000 nmol/serving and 902,880 nmol/serving) and spermidine (137,682 nmol/serving and 221,111 nmol/serving), and green pea soup contains the highest concentration of spermine (36,988 nmol/serving). The polyamine database and FFQ were tested with a convenience sample (n=165). Average daily polyamine intakes from the sample were: 159,133 nmol/day putrescine, 54,697 nmol/day spermidine, and 35,698 nmol/day spermine. Orange and grapefruit juices contributed the greatest amount of putrescine (44,441 nmol/day) to the diet. Green peas contributed the greatest amount of spermidine (3,283 nmol/day) and ground meat contributed the greatest amount of spermine (2,186 nmol/day). Development of this database linked to an FFQ provides a means of estimating polyamine intake and contributes to investigations relating polyamines to cancer.

Enhancement of growth and polysaccharide production in suspension cultures of protocorm-like bodies from Dendrobium huoshanense by the addition of putrescine.

Putrescine at 0.6 mM stimulated protocorm-like body growth and polysaccharide synthesis in suspension cultures of Dendrobium huoshanense. The specific growth rate of protocorm-like body increased from 0.047 to 0.056 day(-1), and the maximum dry weight and polysaccharide production reached 33.2 and 2.94 g l(-1), respectively, while they were 24.6 and 2.12 g l(-1), respectively, in the control. The administration of polyamine inhibitor, alpha-DL-difluoromethylarginine, at 1 mM, decreased protocorm-like body growth and polysaccharide production to 21.4 and 1.76 g l(-1), respectively.

Modulation of N-nitrosodimethylamine kidney tumorigenesis by unilateral hydronephrosis and multiple putrescine administrations.

The effects of unilateral hydronephrosis by ligation of the right ureter and/or multiple injections of putrescine on kidney tumorigenesis by a single intrarenal injection of N-nitrosodimethylamine (DMN) were studied. Inbred female W rats in the unilateral hydronephrotic groups given or not given putrescine developed kidney tumors and/or neoplastic or preneoplastic lesions of the liver at an incidence of 55.6%. Almost all kidney tumors developed in the contralateral kidneys, which showed hypertrophy due to unilateral hydronephrosis. Rats having unilateral hydronephrosis and subjected to long-term putrescine administration after DMN injection frequently contracted large mesenchymal cell tumors (83%), whereas the group not given putrescine developed no mesenchymal cell tumors. Histologically, epithelial cell tumors showed a marked decrease in both gamma-glutamyltransferase activity and trypan blue uptake, but mesenchymal cell tumors did not.

Mastitis Modifies the Biogenic Amines Profile in Human Milk, with Significant Changes in the Presence of Histamine, Putrescine and Spermine.

Biogenic amines (BAs) are low molecular weight nitrogenous organic compounds with different biological activities. Putrescine, spermidine and spermine are essential for the development of the gut and immune system of newborns, and are all found in human milk. Little is known, however, about the role of histamine, tyramine or cadaverine in breast milk. Nor is it known whether mastitis alters the BA composition of milk. The BA profile of human milk, and the influence of mastitis on BA concentrations, were therefore investigated. Putrescine, spermidine and spermine were the main BAs detected. In mastitis-affected milk, the concentrations of putrescine, spermine and histamine were higher.

Polyamine oxidase and tissue transglutaminase activation in rat small intestine by polyamines.

Polyamine degradation was studied in the small intestine from rats fed on a polyamine-supplemented diet. Lactalbumin diet was given to Hooded-Lister rats, with or without 5 mg rat(-1) day(-1) of putrescine or spermidine for 5 days. Polyamine oxidase activity increased with putrescine and spermidine in the diet, whereas spermidine/spermine N(1)-acetyltransferase and diamine oxidase activities were unchanged. We also studied the calcium-dependent and -independent tissue transglutaminase activities, since they can modulate intestinal polyamine levels. Both types of enzymes increased in the cytosolic fraction after putrescine (about 65%) or spermidine (80-100%). Our results indicate that exogenous polyamines stimulate intestinal polyamine oxidase and tissue transglutaminase activities, probably to prevent polyamine accumulation, when other pathways of polyamine catabolism (acetylation and terminal catabolism) are not activated.

Oxidative degradation of polyamines in rat pancreatic hypertrophy.

In the hypertrophic pancreas, we studied the oxidative degradation of polyamines, which are endogenous polycations important for cell division, growth and differentiation. To induce pancreatic hypertrophy, rats were fed on a semi-synthetic diet containing a daily dose of 42 mg phytohaemagglutinin per rat for 5 or 10 days. In the model, the activities of polyamine oxidase (the enzyme that degrades spermidine, spermine and mainly their acetyl derivatives) and diamine oxidase (the key enzyme of terminal catabolism of polyamines in vivo) increased by 100-180% and 90-100%, respectively, parallel to an elevation in polyamine content (40-100%). The results suggest that in pancreas hypertrophy, which does not exhibit stimulation of spermidine/spermine N1-acetyltransferase activity, increases in the activity of polyamine and diamine oxidases are related events that lead to putrescine formation and removal of excess polyamines.