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Background and Aim: The mechanism of pancreatic fibrosis is unclear. Taurine is used in the clinical treatment of a wide variety of diseases, but its effect on improving pancreatic fibrosis is unknown. We examined whether a diet with added taurine improves pancreatic fibrosis induced by dibutyltin dichloride (DBTC) in an experimental chronic pancreatitis rat model. In addition, we examined the influence of taurine on pancreatic stellate cells. Methods: Pancreatic fibrosis was induced by DBTC. Rats were fed a taurine-containing diet or a normal diet and were killed at 4 weeks. Pancreatic stellate cells were isolated from male Wistar rats. Cultured pancreatic stellate cells were incubated with or without taurine chloramine. Type I collagen and transforming growth factor-β1 secretion was evaluated by ELISA, and matrix metalloproteinase activity was assessed by gelatin zymography. Interleukin-6, interleukin-2, and transforming growth factor-β1 levels in the supernatants of pancreatic tissue homogenates were measured. Results: Pancreatic fibrosis induced by DBTC was improved remarkably by the oral administration of the taurine-containing diet. Taurine chloramine decreased type I collagen, transforming growth factor-β1, and matrix metalloproteinases 2 of the pancreatic stellate cell culture supernatant. Increased interleukin-6 and decreased interleukin-2 were found in the supernatants of the pancreatic tissue homogenates of DBTC-induced pancreatitis rats compared with other groups. Conclusion: The oral administration of taurine improves pancreatic fibrosis. Taurine chloramine inhibits transforming growth factor-β1 produced from activated pancreatic stellate cells and improves pancreatic fibrosis. [ABSTRACT FROM AUTHOR]

Background and Aim: Free radicals are reported to be associated with fibrosis in the pancreas. It is generally accepted that pancreatic stellate cells (PSC) play an important role in pancreatic fibrosis. However, the exact role of free radicals in activation of PSC has not been fully elucidated. In the present study, using a superoxide dismutase (SOD) inhibitor, diethyldithiocarbamate (DDC) with cultured PSC, we investigated how free radicals act on the activation of PSC. Methods: PSC were isolated from male Wister rats. Cultured rat PSC were incubated with DDC for 48 h. Intracellular SOD activity and lipid peroxidation were examined in DDC-treated PSC. Activation of PSC was examined by determining the expression of α-smooth muscle actin (α-SMA) by immunocytochemistry. The number of PSC using a hemocytometer, type I collagen secretion with ELISA and matrix metalloproteinases (MMP) activities with gelatin zymography were also examined. Secretion of transforming growth factor-β1 (TGF-β1) was evaluated by ELISA. The effects of the allopurinol, a xanthine oxidase (XOD) inhibitor, on PSC were also examined. Results: DDC decreased SOD activity and increased lipid peroxidation products in PSC. DDC activated PSC, increasing the number of α-SMA positive cells, enhancing secretion of type I collagen and MMP, inhibiting PSC proliferation. Secretion of TGF-β1, which is known to activate PSC, was increased by DDC treatment. These alterations were prevented by allopurinol. Conclusion: These results suggest that free radicals generated by XOD might directly activate PSC. [ABSTRACT FROM AUTHOR]

An oral trypsin inhibitor, camostat (CM), has a beneficial effect on chronic pancreatitis, but its mechanism is not yet fully understood. Recently, pancreatic stellate cells (PSC) have been reported to play an essential role in pancreatic fibrosis. An experimental model of pancreatic fibrosis induced by a superoxide dismutase (SOD) inhibitor (diethyldithiocarbamate[DDC]) was developed in rats. Thus, the effect of an oral trypsin inhibitor on pancreatic fibrosis and PSC was investigated.Pancreatic fibrosis was induced in rats using DDC (DDC rats). DDC + CM rats were administered DDC, and subsequently were fed a diet containing CM. Immunohistochemistry of the pancreas was performed with monoclonal anti-α-smooth muscle actin (α-SMA) antibody and anti-desmin antibody.The DDC rats showed a significant increase inα-SMA-positive cells or desmin-positive cells compared with control rats. These significant increases in the fibrotic area improved after treatment with CM. The level of prolyl hydroxylase in the pancreas, which significantly increased as a result of DDC, decreased after treatment with CM.Camostat has a beneficial effect on pancreatic fibrosis induced by the administration of a SOD inhibitor, which inhibits the proliferation and activation of PSC. [ABSTRACT FROM AUTHOR]

Impaired gallbladder contraction and rapid gastric emptying in patients with chronic pancreatitis may be the result of depleted pancreatic exocrine function. The authors tested whether oral pancreatic enzymes can improve the dysmotility or not. Study subjects consisted of 15 patients with chronic pancreatitis and 18 healthy controls. The gastric emptying time and gallbladder contraction were studied. All patients were initially studied using a test meal without pancreatic enzymes, followed on separate days by a test meal with a single and a triple dose of pancreatic enzymes. Blood samples were taken before and 2 h after the test meal to determine the pancreatic polypeptide levels. In patients with chronic pancreatitis, gallbladder contraction at 15 min after the meal was impaired. The gastric emptying time was faster and the ratio of pre- to postprandial pancreatic polypeptide levels was enhanced. A single dose and a triple dose of oral enzymes further improved the gastric emptying time and the pancreatic polypeptide ration, but did not improve the gallbladder contraction rate at 15 min. It was demonstrated that the oral pancreatic enzymes improved the gastric dysmotility, confirming the previous findings that suggested the depleted pancreatic enzyme output caused the dysmotility. © 2004 Blackwell Publishing Asia Pty Ltd [ABSTRACT FROM AUTHOR]