Oxidative stress is considered to be an important regulator of the pathogenesis of acute pancreatitis. Reactive oxygen species (ROS) regulate the activation of inflammatory cascades, the recruitment of inflammatory ce...Oxidative stress is considered to be an important regulator of the pathogenesis of acute pancreatitis. Reactive oxygen species (ROS) regulate the activation of inflammatory cascades, the recruitment of inflammatory cells and tissue damage in acute pancreatitis. A hallmark of the inflammatory response in pancreatitis is the induction of cytokine expression, which is regulated by a number of signaling molecules including oxidant-sensitive transcription factors such as nuclear factor-κB (NF-κB) and activator protein-1 (AP-1), signal transducer and activator of transcription 3 (STAT3), and mitogen-activated protein kinases (MAPKs). Cross-talk between ROS and pro-inflammatory cytokines is mediated by NF-κB, AP-1, STAT3, and MAPKs; this crosstalk amplifies the inflammatory cascade in acute pancreatitis. Therapeutic studies have shown that antioxidants and natural compounds can have beneficial effects for patients with pancreatitis and can also influence the expression of proinflammatory cytokines in cerulein-induced pancreatitis. Since oxidative stress may activate inflammatory signaling pathways and contribute to the development of pancreatitis, antioxidant therapy may alleviate the symptoms or prevent the development of pancreatitis. Since chronic administration of high doses of antioxidants may have deleterious effects, dosage levels and duration of antioxidant treatment should be carefully determined.展开更多
AIM:To investigate the effects of long term pretreatment with low-,medium-and high-dose aspirin(acetylsalicylic acid,ASA) on a model of acute pancreatitis(AP) induced in rats.METHODS:Forty male Wistar rats were used.T...AIM:To investigate the effects of long term pretreatment with low-,medium-and high-dose aspirin(acetylsalicylic acid,ASA) on a model of acute pancreatitis(AP) induced in rats.METHODS:Forty male Wistar rats were used.Three experimental groups,each consisting of eight animals,received low-(5 mg/kg per day),medium-(150 mg/kg per day) and high-dose(350 mg/kg per day) ASA in supplemented pellet chow for 100 d.Eight animals,serving as the AP-control group,and another eight,serving as reference value(RV) group,were fed with standard pellet chow for the same period.After pretreatment,AP was induced in the experimental animals by intraperitoneal administration of cerulein(2 × 50 μg/kg),while the RV group received saline in the same way.Twelve hours after the second injection,the animals were sacrificed.Pancreatic tissue and plasma samples were collected.One part of the collected pancreatic tissues was used for histopathological evaluation,and the remaining portion was homogenized.Cytokine levels [tumor necrosis factor,interleukin(IL)1β,IL-6],hemogram parameters,biochemical parameters(amylase and lipase),nuclear factor-κB,aspirin triggered lipoxins and parameters related to the antioxidant system(malondialdehyde,nitric oxide,hemeoxygenase-1,catalase and superoxide dismutase) were measured.RESULTS:Cerulein administration induced mild pancreatitis,characterized by interstitial edema(total histopathological score of 5.88 ± 0.44vs 0.25 ± 0.16,P < 0.001).Subsequent pancreatic tissue damage resulted in an increase in amylase(2829.71 ± 772.48 vs 984.57 ± 49.22 U/L,P = 0.001) and lipase(110.14 ± 75.84 U/L vs 4.71 ± 0.78 U/L,P < 0.001) in plasma,and leucocytes(6.89 ± 0.48 vs 4.36 ± 0.23,P = 0.001) in peripheral blood.Cytokines,IL-1β(18.81 ± 2.55 pg/μg vs 6.65 ± 0.24 pg/μg,P = 0.002) and IL-6(14.62 ± 1.98 pg/μg vs 9.09 ± 1.36 pg/μg,P = 0.04) in pancreatic tissue also increased.Aspirin pretreatment reduced the increase in the aforementioned parameters to a certain degree and partially improved the histopathologic展开更多
AIM： To observe the expressions of early growth response factor-1 （Egr-1） and tissue factor （TF） in rats with cerulein-induced acute pancreatitis and to explore its significance. METHODS： A large dose of cerulei...AIM： To observe the expressions of early growth response factor-1 （Egr-1） and tissue factor （TF） in rats with cerulein-induced acute pancreatitis and to explore its significance. METHODS： A large dose of cerulein was used to create the experimental acute pancreatitis model in rats. The changes of Egr-1 mRNA and protein in rats were observed during 30 min to 4 h after the treatment and immunohistochemical method was used to observe the localized expression of Egr-1 in tissues. In addition to the mRNA expression of Egr-1 target gene, TF was also observed. A blank control group, and a bombesinadministered group were used for comparison. RESULTS： Alter the stimulation of a large dose of cerulein, the rats showed typical inflammatory changes of acute pancreatitis. Thirty minutes alter the stimulation, the mRNA expression of Egr-1 in the pancreatic tissue reached its peak and then declined, while the expression of Egr-1 protein reached its peak 2 h after the stimulation. Histologically, 2 h after the stimulation, almost all pancreatic acinar cells had the expression of Egr-1 protein, which was focused in the nuclei. The mRNA expression of TF occurred 1 h after the stimulation and gradually increased within 4 h. However, a large dose of bombesin only stimulated the pancreatic tissue to produce a little mRNA expression of Egr-1 and no mRNA expression of Egr-1 protein and TF. CONCLUSION： Egr-1 as a pro-inflammatory transcription factor may play an important role in the pathogenesis of acute pancreatitis by modulating the expression of TF.展开更多
AIM： To investigate the effect of Garden/a fasm/noides （GJ） on cerulein-induced acute pancreatitis （AP） in mice. METHODS： C57BL/6 mice weighing 18-20 g were divided into three groups. （1） Normal salinetreated ...AIM： To investigate the effect of Garden/a fasm/noides （GJ） on cerulein-induced acute pancreatitis （AP） in mice. METHODS： C57BL/6 mice weighing 18-20 g were divided into three groups. （1） Normal salinetreated group, （2） treatment with GJ at a dose of 0.1 g/kg, （3） treatment with GJ at a dose of 1 g/kg. GJ was administered orally （n = 6 per group） for 1 wk. Three hours later, the mice were given anintraperitoneal injection of cerulein （50 μg/kg）, a stable cholecystokinin （CCK） analogue, every hour for a total of 6h as described previously. The mice were sacrificed at 6 h after completion of cerulein injections. Blood samples were obtained to determine serum amylase, lipase and cytokine levels. The pancreas was rapidly removed for morphologic examination and scoring. A portion of pancreas was stored at -70℃ and prepared for the measurement of tissue myeloperoxidase （MPO） activity, an indicator of neutrophil sequestration, and for reverse-transcriptase PCR （RT-PCR） and real-time PCR measurements. RESULTS： Treatment with G.1 decreased significantly the severity of pancreatitis and pancreatitis-associated lung injury. Treatment with G.1 attenuated the severity of AP compared with saline-treated mice, as shown by reduction in pancreatic edema, neutrophil infiltration, serum amylase and lipase levels, serum cytokine levels, and mRNA expression of multiple inflammatory mediators. CONCLUSION： These results suggest that GJ attenuated the severity of AP as well as pancreatitisassociated lung injury.展开更多
AIM: To evaluate the therapeutic role of caffeic acid phenethyl ester (CAPE) in a rat model of ceruleaninduced acute pancreatitis (AP).METHODS: Seventy male Wistar albino rats were divided into seven groups. Acute ede...AIM: To evaluate the therapeutic role of caffeic acid phenethyl ester (CAPE) in a rat model of ceruleaninduced acute pancreatitis (AP).METHODS: Seventy male Wistar albino rats were divided into seven groups. Acute edematous pancreatitis was induced by subcutaneous cerulein injection (20 μg/kg) four times at 1-h intervals. CAPE (30 mg/kg) was given by subcutaneous injection at the beginning (CAPE 1 group) and 12 h after the last cerulein injection (CAPE 2 group). Serum amylase, lipase, white blood cell count, and tumor necrosis factor (TNF)-α levels were measured, and pancreatic histopathology was assessed. RESULTS: In the AP group, amylase and lipase levels were found to be elevated and the histopathological evaluation showed massive edema and inflammation of the pancreas, with less fatty necrosis when compared with sham and control groups. Amylase and lipase levels and edema formation decreased signif icantly in the CAPE therapy groups (P < 0001); especially in the CAPE 2 group, edema was improved nearly completely (P = 0001). Inflammation and fatty necrosis were partially recovered by CAPE treatment. The pathologicalresults and amylase level in the placebo groups were similar to those in the AP group. White blood cell count and TNF-α concentration was nearly the same in the CAPE and placebo groups.CONCLUSION: CAPE may be useful agent in treatment of AP but more experimental and clinical studies are needed to support our observation of benef icial effects of CAPE before clinical usage of this agent.展开更多
BACKGROUND： Oxidative stress is recognized as a pivotal effector of several pathogenic processes, including acute pancreatitis. Reactive oxygen species not just cause damage on the main cellular components, but also ...BACKGROUND： Oxidative stress is recognized as a pivotal effector of several pathogenic processes, including acute pancreatitis. Reactive oxygen species not just cause damage on the main cellular components, but also influence the expression of antioxidant system genes. Antioxidant molecules, such as melatonin, could be good candidates for the treatment of this multidimensional disease. The present study was to evaluate the chemopreventive effect of melatonin in a rat model of ceruleininduced acute pancreatitis.METHODS： Four subcutaneous injections of cerulein（20 μg/kg body weight） were given to Wistar rats at two hours intervals;melatonin was injected intraperitoneally（25 mg/kg body weight）30 minutes before each injection of cerulein. Lipid peroxidation,protein oxidation（carbonyl groups）, total antioxidant status,and glutathione peroxidase activity were determined in pancreatic tissue using commercial kits.RESULTS： The chemopreventive administration of melatonin caused a reduction in lipid peroxidation and protein oxidation due to injections of cerulein. Additionally, melatonin treatment was also able to revert glutathione peroxidase activity and total antioxidant status near to control levels, suggesting that melatonin could prevent from oxidative phenomena in the pancreas, such as lipid peroxidation and protein oxidation,and could stimulate, directly or indirectly, the expression of antioxidant enzymes.CONCLUSION： Melatonin, a polyvalent antioxidant, protected the pancreatic damage via the decrease of oxidative stress andincrease of the activities of antioxidant enzymes in ceruleininduced acute pancreatitis.展开更多
Acute pancreatitis(AP) is an inflammatory disease characterized by acute inflammation and necrosis of the pancreatic parenchyma. AP is often associated with organ failure, sepsis, and high mortality. The pathogenesis ...Acute pancreatitis(AP) is an inflammatory disease characterized by acute inflammation and necrosis of the pancreatic parenchyma. AP is often associated with organ failure, sepsis, and high mortality. The pathogenesis of AP is still not well understood. In recent years several papers have highlighted the cellular and molecular events of acute pancreatitis. Pancreatitis is initiated by activation of digestive enzymes within the acinar cells that are involved in autodigestion of the gland, followed by a massive infiltration of neutrophils and macrophages and release of inflammatory mediators, responsible for the local and systemic inflammatory response. The hallmark of AP is parenchymal cell necrosis that represents the cause of the high morbidity and mortality, so that new potential therapeutic approaches are indispensable for the treatment of patients at high risk of complications. However, not all factors that determine the onset and course of the disease have been explained. Aim of this article is to review the role of mitogen-activated protein kinases in pathogenesis of acute pancreatitis.展开更多
INTRODUCTIONAmino acid consumption test (AACT) has a highsensitivity and specificity in evaluating exocrinepancreatic insufficiency,but its diagnostic valueto exocrine pancreatic insufficiency in Chinese hasnot been w...INTRODUCTIONAmino acid consumption test (AACT) has a highsensitivity and specificity in evaluating exocrinepancreatic insufficiency,but its diagnostic valueto exocrine pancreatic insufficiency in Chinese hasnot been well understood.In this study,the oralreagent stimulating pancreatic secretion (O-AACT)was used instead of cerulein(I-AACT) for amidoacid consumption test and the dignostic efficiency ofO-AACT was evaluated and compared with I-AACTon the exocrine pancreatic insufficiency in Chinese.展开更多
基金Supported by National Research Foundation of Korea grant funded by the Korea government No.2007-0056092
文摘Oxidative stress is considered to be an important regulator of the pathogenesis of acute pancreatitis. Reactive oxygen species (ROS) regulate the activation of inflammatory cascades, the recruitment of inflammatory cells and tissue damage in acute pancreatitis. A hallmark of the inflammatory response in pancreatitis is the induction of cytokine expression, which is regulated by a number of signaling molecules including oxidant-sensitive transcription factors such as nuclear factor-κB (NF-κB) and activator protein-1 (AP-1), signal transducer and activator of transcription 3 (STAT3), and mitogen-activated protein kinases (MAPKs). Cross-talk between ROS and pro-inflammatory cytokines is mediated by NF-κB, AP-1, STAT3, and MAPKs; this crosstalk amplifies the inflammatory cascade in acute pancreatitis. Therapeutic studies have shown that antioxidants and natural compounds can have beneficial effects for patients with pancreatitis and can also influence the expression of proinflammatory cytokines in cerulein-induced pancreatitis. Since oxidative stress may activate inflammatory signaling pathways and contribute to the development of pancreatitis, antioxidant therapy may alleviate the symptoms or prevent the development of pancreatitis. Since chronic administration of high doses of antioxidants may have deleterious effects, dosage levels and duration of antioxidant treatment should be carefully determined.
基金Supported by The Istanbul University Department of Scientific Research Projects,Grant No. 3101
文摘AIM:To investigate the effects of long term pretreatment with low-,medium-and high-dose aspirin(acetylsalicylic acid,ASA) on a model of acute pancreatitis(AP) induced in rats.METHODS:Forty male Wistar rats were used.Three experimental groups,each consisting of eight animals,received low-(5 mg/kg per day),medium-(150 mg/kg per day) and high-dose(350 mg/kg per day) ASA in supplemented pellet chow for 100 d.Eight animals,serving as the AP-control group,and another eight,serving as reference value(RV) group,were fed with standard pellet chow for the same period.After pretreatment,AP was induced in the experimental animals by intraperitoneal administration of cerulein(2 × 50 μg/kg),while the RV group received saline in the same way.Twelve hours after the second injection,the animals were sacrificed.Pancreatic tissue and plasma samples were collected.One part of the collected pancreatic tissues was used for histopathological evaluation,and the remaining portion was homogenized.Cytokine levels [tumor necrosis factor,interleukin(IL)1β,IL-6],hemogram parameters,biochemical parameters(amylase and lipase),nuclear factor-κB,aspirin triggered lipoxins and parameters related to the antioxidant system(malondialdehyde,nitric oxide,hemeoxygenase-1,catalase and superoxide dismutase) were measured.RESULTS:Cerulein administration induced mild pancreatitis,characterized by interstitial edema(total histopathological score of 5.88 ± 0.44vs 0.25 ± 0.16,P < 0.001).Subsequent pancreatic tissue damage resulted in an increase in amylase(2829.71 ± 772.48 vs 984.57 ± 49.22 U/L,P = 0.001) and lipase(110.14 ± 75.84 U/L vs 4.71 ± 0.78 U/L,P < 0.001) in plasma,and leucocytes(6.89 ± 0.48 vs 4.36 ± 0.23,P = 0.001) in peripheral blood.Cytokines,IL-1β(18.81 ± 2.55 pg/μg vs 6.65 ± 0.24 pg/μg,P = 0.002) and IL-6(14.62 ± 1.98 pg/μg vs 9.09 ± 1.36 pg/μg,P = 0.04) in pancreatic tissue also increased.Aspirin pretreatment reduced the increase in the aforementioned parameters to a certain degree and partially improved the histopathologic
基金Supported by the National Natural Science Foundation of China,No. 30370648
文摘AIM： To observe the expressions of early growth response factor-1 （Egr-1） and tissue factor （TF） in rats with cerulein-induced acute pancreatitis and to explore its significance. METHODS： A large dose of cerulein was used to create the experimental acute pancreatitis model in rats. The changes of Egr-1 mRNA and protein in rats were observed during 30 min to 4 h after the treatment and immunohistochemical method was used to observe the localized expression of Egr-1 in tissues. In addition to the mRNA expression of Egr-1 target gene, TF was also observed. A blank control group, and a bombesinadministered group were used for comparison. RESULTS： Alter the stimulation of a large dose of cerulein, the rats showed typical inflammatory changes of acute pancreatitis. Thirty minutes alter the stimulation, the mRNA expression of Egr-1 in the pancreatic tissue reached its peak and then declined, while the expression of Egr-1 protein reached its peak 2 h after the stimulation. Histologically, 2 h after the stimulation, almost all pancreatic acinar cells had the expression of Egr-1 protein, which was focused in the nuclei. The mRNA expression of TF occurred 1 h after the stimulation and gradually increased within 4 h. However, a large dose of bombesin only stimulated the pancreatic tissue to produce a little mRNA expression of Egr-1 and no mRNA expression of Egr-1 protein and TF. CONCLUSION： Egr-1 as a pro-inflammatory transcription factor may play an important role in the pathogenesis of acute pancreatitis by modulating the expression of TF.
基金The Ministry of Science & Technology (MoST)/Korea Science & Engineering Foundation (KOSEF) through the Vestibulocochlear Research Center (VCRC) at Wonkwang University (R13-2002-055-00000-0)
文摘AIM： To investigate the effect of Garden/a fasm/noides （GJ） on cerulein-induced acute pancreatitis （AP） in mice. METHODS： C57BL/6 mice weighing 18-20 g were divided into three groups. （1） Normal salinetreated group, （2） treatment with GJ at a dose of 0.1 g/kg, （3） treatment with GJ at a dose of 1 g/kg. GJ was administered orally （n = 6 per group） for 1 wk. Three hours later, the mice were given anintraperitoneal injection of cerulein （50 μg/kg）, a stable cholecystokinin （CCK） analogue, every hour for a total of 6h as described previously. The mice were sacrificed at 6 h after completion of cerulein injections. Blood samples were obtained to determine serum amylase, lipase and cytokine levels. The pancreas was rapidly removed for morphologic examination and scoring. A portion of pancreas was stored at -70℃ and prepared for the measurement of tissue myeloperoxidase （MPO） activity, an indicator of neutrophil sequestration, and for reverse-transcriptase PCR （RT-PCR） and real-time PCR measurements. RESULTS： Treatment with G.1 decreased significantly the severity of pancreatitis and pancreatitis-associated lung injury. Treatment with G.1 attenuated the severity of AP compared with saline-treated mice, as shown by reduction in pancreatic edema, neutrophil infiltration, serum amylase and lipase levels, serum cytokine levels, and mRNA expression of multiple inflammatory mediators. CONCLUSION： These results suggest that GJ attenuated the severity of AP as well as pancreatitisassociated lung injury.
文摘AIM: To evaluate the therapeutic role of caffeic acid phenethyl ester (CAPE) in a rat model of ceruleaninduced acute pancreatitis (AP).METHODS: Seventy male Wistar albino rats were divided into seven groups. Acute edematous pancreatitis was induced by subcutaneous cerulein injection (20 μg/kg) four times at 1-h intervals. CAPE (30 mg/kg) was given by subcutaneous injection at the beginning (CAPE 1 group) and 12 h after the last cerulein injection (CAPE 2 group). Serum amylase, lipase, white blood cell count, and tumor necrosis factor (TNF)-α levels were measured, and pancreatic histopathology was assessed. RESULTS: In the AP group, amylase and lipase levels were found to be elevated and the histopathological evaluation showed massive edema and inflammation of the pancreas, with less fatty necrosis when compared with sham and control groups. Amylase and lipase levels and edema formation decreased signif icantly in the CAPE therapy groups (P < 0001); especially in the CAPE 2 group, edema was improved nearly completely (P = 0001). Inflammation and fatty necrosis were partially recovered by CAPE treatment. The pathologicalresults and amylase level in the placebo groups were similar to those in the AP group. White blood cell count and TNF-α concentration was nearly the same in the CAPE and placebo groups.CONCLUSION: CAPE may be useful agent in treatment of AP but more experimental and clinical studies are needed to support our observation of benef icial effects of CAPE before clinical usage of this agent.
基金supported by grants from MICINNFEDER(BFU2010-15049)Gobierno de Extremadura(Re:GRU10003)Plan of Recruitment and Training of Human Resources on Research of University of Extremadura(1076)
文摘BACKGROUND： Oxidative stress is recognized as a pivotal effector of several pathogenic processes, including acute pancreatitis. Reactive oxygen species not just cause damage on the main cellular components, but also influence the expression of antioxidant system genes. Antioxidant molecules, such as melatonin, could be good candidates for the treatment of this multidimensional disease. The present study was to evaluate the chemopreventive effect of melatonin in a rat model of ceruleininduced acute pancreatitis.METHODS： Four subcutaneous injections of cerulein（20 μg/kg body weight） were given to Wistar rats at two hours intervals;melatonin was injected intraperitoneally（25 mg/kg body weight）30 minutes before each injection of cerulein. Lipid peroxidation,protein oxidation（carbonyl groups）, total antioxidant status,and glutathione peroxidase activity were determined in pancreatic tissue using commercial kits.RESULTS： The chemopreventive administration of melatonin caused a reduction in lipid peroxidation and protein oxidation due to injections of cerulein. Additionally, melatonin treatment was also able to revert glutathione peroxidase activity and total antioxidant status near to control levels, suggesting that melatonin could prevent from oxidative phenomena in the pancreas, such as lipid peroxidation and protein oxidation,and could stimulate, directly or indirectly, the expression of antioxidant enzymes.CONCLUSION： Melatonin, a polyvalent antioxidant, protected the pancreatic damage via the decrease of oxidative stress andincrease of the activities of antioxidant enzymes in ceruleininduced acute pancreatitis.
文摘Acute pancreatitis(AP) is an inflammatory disease characterized by acute inflammation and necrosis of the pancreatic parenchyma. AP is often associated with organ failure, sepsis, and high mortality. The pathogenesis of AP is still not well understood. In recent years several papers have highlighted the cellular and molecular events of acute pancreatitis. Pancreatitis is initiated by activation of digestive enzymes within the acinar cells that are involved in autodigestion of the gland, followed by a massive infiltration of neutrophils and macrophages and release of inflammatory mediators, responsible for the local and systemic inflammatory response. The hallmark of AP is parenchymal cell necrosis that represents the cause of the high morbidity and mortality, so that new potential therapeutic approaches are indispensable for the treatment of patients at high risk of complications. However, not all factors that determine the onset and course of the disease have been explained. Aim of this article is to review the role of mitogen-activated protein kinases in pathogenesis of acute pancreatitis.
基金the Science Fund of Department of Health,Sichuan Province,No.9241-920054
文摘INTRODUCTIONAmino acid consumption test (AACT) has a highsensitivity and specificity in evaluating exocrinepancreatic insufficiency,but its diagnostic valueto exocrine pancreatic insufficiency in Chinese hasnot been well understood.In this study,the oralreagent stimulating pancreatic secretion (O-AACT)was used instead of cerulein(I-AACT) for amidoacid consumption test and the dignostic efficiency ofO-AACT was evaluated and compared with I-AACTon the exocrine pancreatic insufficiency in Chinese.
