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Experimental pancreatitis is associated with activation of polyamine catabolism. The polyamine analog bismethylspermine (Me(2)Spm) can ameliorate pancreatic injury. We investigated the roles of polyamine catabolism in remote organs during pancreatitis and explored the mechanism of polyamine catabolism by administering Me(2)Spm. Acute pancreatitis was induced by an infusion of 2 or 6% taurodeoxycholate before Me(2)Spm administration. Blood, urine and tissues were sampled at 24 and 72 h to assess multi-organ injury and polyamine catabolism. The effect of Me(2)Spm on mortality in experimental pancreatitis was tested separately. Liver putrescine levels were elevated following liver injury. Me(2)Spm increased the activity of spermidine/spermine N(1)-acetyltransferase (SSAT) and depleted the spermidine, spermine or putrescine levels. Lung putrescine levels increased, and SSAT and spermine decreased following lung injury. Me(2)Spm enhanced the activity of SSAT and decreased the spermidine and spermine levels. Renal injury was manifested as an increase in creatinine or a decrease in urine output. Decreases in kidney SSAT, spermidine or spermine and an increase in putrescine were found during pancreatitis. In the 2% taurodeoxycholate model, Me(2)Spm decreased urine output and raised plasma creatinine levels. Me(2)Spm increased SSAT and decreased polyamines. Excessive Me(2)Spm accumulated in the kidney, and greater amounts were found in the 6% taurodeoxycholate model in which this mortality was not reduced by Me(2)Spm. In the 2% taurodeoxycholate model, Me(2)Spm dose-dependently induced mortality at 72 h. Like pancreatic injury, remote organ injury in pancreatitis is associated with increased putrescine levels. However, Me(2)Spm could not ameliorate multi-organ injury. Me(2)Spm administration was associated with significant renal toxicity and induced mortality, suggesting that the current dose is too high and needs to be modified.

Background: Overinduced polyamine catabolism (PC) in a transgenic rat model has been suggested to be a mediator of trypsin activation which is important in acinar cell necrosis. PC has also been observed in experimental taurodeoxycholate pancreatitis. We hypothesized that PC may be a mediator of trypsin activation in taurodeoxycholate pancreatitis., Methods: Pancreatitis was induced in wild-type rats by 2 or 6% taurodeoxycholate infusion or in transgenic rats by overexpressing spermidine/spermine N(1)-acetyltransferase (SSAT). The time courses of necrosis, caspase-3 immunostaining, SSAT, polyamine levels, and trypsinogen activation peptide (TAP) were monitored. The effect of the polyamine analogue bismethylspermine (Me(2)Spm) was investigated., Results: In a transgenic pancreatitis model, TAP and acinar necrosis increased simultaneously after the activation of SSAT, depletion of spermidine, and development of apoptosis. In taurodeoxycholate pancreatitis, necrosis developed along with the accumulation of TAP. SSAT was activated simultaneously or after TAP accumulation and less than in the transgenic model, with less depletion of spermidine than in the transgenic model. Supplementation with Me(2)Spm ameliorated the extent of acinar necrosis at 24 h, but contrary to previous findings in the transgenic model, in the taurodeoxycholate model it did not affect trypsin activation. Compared with the transgenic model, no extensive apoptosis was found in taurodeoxycholate pancreatitis., Conclusions: Contrary to transgenic SSAT-overinduced pancreatitis, PC may not be a mediator of trypsin activation in taurodeoxycholate pancreatitis. The beneficial effect of polyamine supplementation on necrosis in taurodeoxycholate pancreatitis may rather be mediated by other mechanisms than amelioration of trypsin activation. and IAP., (Copyright © 2011 S. Karger AG, Basel.)

Objective: Experimental studies have shown that pancreatic activation of polyamine catabolism occurs during the early stage of acute pancreatitis. Changes in pancreatic polyamines are reflected in the red blood cell (RBC) polyamine contents, correlating with the extent of pancreatic necrosis. The aim of this human study was to examine the changes in polyamine levels in the RBCs of patients with acute pancreatitis., Material and Methods: Twenty-four patients with acute pancreatitis (7 alcoholic, 10 gallstone and 7 of unknown etiology) were recruited in the study. Eighteen patients with non-pancreatic acute abdominal diseases were included as controls, and 6 volunteers were studied as references. Blood samples were collected on admission and during hospitalization to assess polyamine levels. After clinical recovery, the patients revisited the clinic, and RBC polyamine levels were measured again. For comparison, plasma interleukin-6 (IL-6), IL-10 and C-reactive protein (CRP) were measured., Results: In acute pancreatitis patients, there was no difference in RBC polyamine levels on admission compared with those in controls or in volunteers. Putrescine levels on admission were higher in patients with pancreatic necrosis than in patients without necrosis, but there was no difference in spermidine and spermine levels. Patients with pancreatitis of unknown etiology had significantly higher levels of polyamines on admission and throughout hospitalization, but they also had more necrosis, which explained the difference in multivariate analysis. Spermidine and spermine levels increased after clinical recovery. RBC putrescine correlated with IL-6 and IL-10, and spermine correlated with CRP., Conclusions: The results of this study suggest that RBC polyamines change in human acute pancreatitis in several respects, as has been previously observed in experimental pancreatitis.

Background: Stable polyamine homeostasis is important for cell survival and regeneration. Our experimental studies have shown that catabolism of spermidine and spermine to putrescine is associated with the development of pancreatitis. We investigated the pathogenetic role of polyamine catabolism by studying the effect of a methylated polyamine analog on taurodeoxycholate-induced acute experimental pancreatitis., Methods: Acute pancreatitis was induced by infusion of sodium taurodeoxycholate (2%) into the pancreatic duct. Bismethylspermine (Me(2)Spm) was administered as a pretreatment before the induction of pancreatitis or as a treatment after the induction of pancreatitis. The sham operation included laparotomy only. Pancreas tissue and blood were sampled at 24 h and 72 h after the infusion of taurodeoxycholate and studied for pancreatitis severity (serum amylase activity, pancreatic water content, and histology) and polyamine catabolism, which includes spermidine/spermine N(1)-acetyltransferase (SSAT) activity as well as spermidine, spermine, and putrescine concentrations in the pancreas., Results: Sodium taurodeoxycholate-induced acute pancreatitis manifests as increases in serum amylase and pancreatic water content, leukocytosis, and acinar cell necrosis in the pancreas. The activity of SSAT increased significantly together with an increase in the ratios of pancreatic putrescine/spermidine and putrescine/spermine at 24 h, which indicates SSAT-induced polyamine catabolism. Pancreatic water content and necrosis were reduced significantly by the treatment with Me(2)Spm at 24 h but not at 72 h when the polyamine homeostasis had recovered, and the pancreatitis had progressed., Conclusions: Taurodeoxycholate-induced acute pancreatitis was associated with activation of polyamine catabolism in the pancreas. The polyamine analog Me(2)Spm ameliorated the injury in the early stage, but it did not ameliorate the late progression of the pancreatic necrosis at 72 h. Thus, besides proteolytic enzyme activation and the cascades of inflammation, polyamine catabolism may be an important pathogenetic mediator of the early stages of acute pancreatitis.

Background: We have experimental data indicating that the pancreas is easily damaged by any intervention. The present study compared the effects of suture diameter, number of needle passes and suture tightness on rat pancreas., Methods: Under anesthesia, rat pancreas was sutured either with one loose stitch of 6-0 polydioxanone (PDS II) or 3-0 PDS II, with 5 passes of loose running 6-0 PDS II, or with 6-0 PDS II loop tightened to 0.6 or 1.2 N. Amylase activity and pancreatic tissue histology at the suturing site and farther away, were evaluated 1, 3, 7 and 21 days postoperatively., Results: Each suturing exposure and the sham-operation induced temporary amylase activity elevation on day 1 when compared with the baseline. In histology, 3-0 suture, 5 needle passes and 1.2-newton loop induced more damage than 6-0 suture, single needle pass and 0.6-newton loop, respectively. Similar but milder changes were observed in samples from the remote site., Conclusions: The pancreas reacts to suturing with widespread injury response resembling that of acute pancreatitis. In attempting to reduce suturing-induced widespread injury, as few and thin sutures and as loose suture tightness as possible should be used. Although these findings may seem obvious, they have not previously been proven in terms of histology., (Copyright 2008 S. Karger AG, Basel.)

Background/aims: Polyamines are essential to survival, growth, and proliferation of mammalian cells. Previous studies have suggested that the pancreatic polyamine levels may change in acute pancreatitis. In this study, the changes of polyamine levels in the pancreas have been studied with respect to the severity of pancreatitis. We investigated whether there is a relationship in polyamine levels between pancreas and blood, and whether pancreatic and blood polyamine levels change according to the severity of pancreatitis., Methods: In rats, sublethal pancreatitis was induced by intraductal infusion of 2% taurodeoxycholate, while lethal pancreatitis was induced with 6% taurodeoxycholate., Results: Infusion of 6% taurodeoxycholate as compared with 2% resulted in more severe pancreatitis, as revealed by mortality, histology, and serum amylase activity. Pancreatic spermidine/spermine N(1)-acetyltransferase was induced early after pancreatitis and was associated with increased putrescine and decreased spermidine levels. The extent of pancreatic necrosis significantly correlated with the polyamine catabolism indicators pancreatic putrescine/spermidine ratio (r = 0.29, p < 0.01) and pancreatic putrescine/spermine ratio (r = 0.32, p < 0.01). The two pancreatic polyamine ratios correlated well also with the red blood cell polyamine ratios (r = 0.75 and r = 0.72, respectively, both p < 0.01). Furthermore, the extent of pancreatic necrosis correlated with red blood cell putrescine/spermidine (r = 0.32, p < 0.01) and putrescine/spermine (r = 0.37, p < 0.01) ratios., Conclusions: Acute experimental pancreatitis is associated with an early pancreatic spermidine/spermine N(1)-acetyltransferase induction and consequent changes in polyamine levels in pancreas and red blood cells, depending on the severity of pancreatitis. Because changes in red blood cell spermidine, spermine, and putrescine levels evolve already early during the time course of pancreatitis, and correlate with the extent of pancreatic necrosis, their clinical value as early markers of the severity of acute pancreatitis needs to be further evaluated. and IAP., (Copyright 2008 S. Karger AG, Basel.)