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Characterization of the nerve-stellate cell interactions in pancreatic cancer
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Abstracts / Pancreatology 14 (2014) S1eS129
Aims: To investigate the effects of LPS and hyperglycemia on PSC activation and effects of simvastatin on LPS induced PSC activation. Materials & methods: Primary cultures of rat PSCs were exposed to various concentrations of glucose and LPS with/without simvastatin. Quantification of proliferation was performed by Brd-U assay. PSC activation was assessed by expression of a-SMA and extracellular signal-regulated kinase (ERK) using Western blot. Results: LPS induced activation and proliferation of PSC. However, glucose did not affect PSC proliferation. The proliferative effect of LPS on PSC was not affected by glucose concentration in culture media. Simvastatin inhibited LPS induced activation and proliferation of PSC. The proliferative effect of LPS was mediated by activation of Erk 1/2 pathway which was effectively inhibited by simvastatin. Conclusion: This study shows that LPS is one of the activating factors toward PSC. Endotoxemia which is frequently encountered in the clinical settings of acute and chronic pancreatitis may act as a triggering factor for initiating and persisting pancreatic fibrosis. Simvastain could be a therapeutic agent for preventing pancreatic fibrosis.
T-017. Oxidative stress and proinflammatory role of pancreatic stellate cells in response to tobacco and alcohol ~ eiras-Alvarin ~ o a, María Luaces-Regueira a, J. Enrique Margarita Castin ~ oz b Domínguez-Mun a
Foundation for Research in Digestive Diseases, Spain University Hospital of Santiago de Compostela. Foundation for Research in Digestive Diseases, Spain b
Background: Smoking and alcohol are recognized risk factors for chronic pancreatitis (CP). Previous studies from our group showed that both toxics are associated with pancreatic fibrosis development mediated by pancreatic stellate cells (PSC) activation. This activation may be regulated by reactive oxygen species (ROS) production and perpetuated by cytokine secretion involved in the inflammatory response. Aims: To study the role of tobacco, as independent factor or associated with alcohol, on oxidative stress production and secretion of proinflammatory cytokines in PSC primary culture. Materials & methods: Isolated PSC from rat pancreas were exposed to tobacco alone (0.01mg/ml) or in combination of increasing concentrations of ethanol (5 to 50mM). ROS production was examined using 2’-7’-dichlorofluorescin diacetate (DCF-DA) and was detected by flow cytometry. Fractalkine secretion as proinflammatory cytokine was evaluated by ELISA. Results are expressed as mean±SEM. Data were analyzed by ANOVA. Results: Alcohol at 50mM alone (3.06±0.77, p¼0.008 vs negative control) or in combination with tobacco (2.68±0.49, p¼0.027 vs negative control) induced ROS production into PSC without a synergic effect of both toxics. Tobacco in combination with 50 mM ethanol induced fractalkine secretion at 48 hours (11.5±3.3 pg/mL vs 5±1.25 pg/mL negative control; p¼0.017). Conclusion: The association of alcohol and tobacco stimulates ROS production and fractalkine secretion in the PSC, thereby perpetuating the activated PSC phenotype. This fact explains the progression of pancreatic fibrosis in patients maintaining alcohol and smoking consumption, and represents the pathophysiological basis for a strict recommendation for drinking and smoking cessation in patients with chronic pancreatitis.
T-018. The role of heat shock protein 70 in pancreatic stellate cells Jong Jin Hyun, Jae Min Lee, Hyo Jung Kim, Jae Seon Kim, Hong Sik Lee, Chang Duck Kim Korea University College of Medicine, Department of Internal Medicine, South Korea Background: The role of heat shock protein 70 (hsp70) in acinar cells (acute pancreatitis) and ductal cells (pancreatic cancer) has been extensively studied. However, the role of hsp70 in pancreatic stellate cell (PSC), an important cell responsible for desmoplastic reaction, is less well understood. Aims: To investigate the role of hsp70 in PSC activation and proliferation. Materials & methods: PSCs were incubated at 42 C for 2hr and recovered at 37 C for 24hr in order to induce hsp70 expression. Cultured PSCs were treated with heat, PDGF, TGF-b, and LPS to measure a-SMA and hsp70 expression by Western blotting. Cell proliferation was measured by BrdU assay. Simvastatin and quercetin were used in order to inhibit PSC proliferation and hsp70 expression, respectively. Results: Overexpression of hsp70 did not affect cytokine induced aSMA expression. Hsp70 expression was significantly increased with PDGF and to a moderate degree with LPS, but not with TGF-b. Similarly, PSC proliferation was also significantly increased by PDGF and to a lesser degree by LPS, but TGF-b did not induce PSC proliferation. Simvastatin suppressed hsp70 expression and PSC proliferation induced by heat or PDGF. Quercetin completely inhibited PDGF-induced hsp70 expression and cell proliferation and partly inhibited heat-induced effects. However, heat preconditioning which induces hsp70 expression had no additional effect on PDGF induced cell proliferation. Conclusion: Hsp70 expression was closely related to cell proliferation in PSCs. Inhibition of hsp70 expression abolished or decreased the effect of PDGF and heat on cell proliferation. Therefore, modulation of hsp70 expression could be an effective therapeutic target for inhibition of pancreatic fibrosis.
T-019. Characterization of the nerve-stellate cell interactions in pancreatic cancer €ß, Ihsan Ekin Demir, Helmut Steffen Teller, Dominic Dischl, Rüdiger Go Friess, Güralp O. Ceyhan Chirurgische Klinik und Poliklinik, Pankreasforschungslabor, Klinikum rechts der Isar, TU München, Ismaninger Straße 22, D-81675, Germany Background: Pancreatic stellate cells (PSC) emerged in recent years as the main actor for the generation of pancreatic fibrosis in pancreatic cancer (PCa). Subsequent to their activation, PSC start to proliferate, migrate, and produce several extracellular matrix (ECM) components as well as cytokines. In this context, neural invasion and pancreatic neuroplasticity is most prominent in the desmoplastic areas. Aims: The present study aims at elucidating the characterisation of the interactions of nerves, carcinoma cells and PSC and the potential impact of PSC during the generation of neuropathic alterations in PCa. Materials & methods: PSC were isolated from Wistar rats and cultivated under hypoxia, stimulated with TGFß or left untreated as controls. After cell lysis, the expression of neurotrophic factors and their receptors (GFRa) was determined by Immunoblotting and by qRT-PCR. For neuroplasticity assays, dorsal root ganglia (DRG) were isolated from newborn
Abstracts / Pancreatology 14 (2014) S1eS129
Wistar rats and treated with supernatants of quiescent and activated PSC. Changes in neurite length, axonal branching, perikaryonal diameter and glial density were determined. Results: PSC produce neurotrophic factors as well as their receptors and alter the expression pattern of neurturin and artemin after activation towards their active forms, whereas the GFRa expression remains unchanged. After treatment of PSC with hypoxia or TGFß, PSC are activated. Cell culture supernatants of activated PSC lead to an increased neurite and glial density in isolated DRG. Conclusion: Activated PSC alter their expression pattern of neurotrophic factors, influence neuroplasticity of isolated DRG and therefore may play a seminal role in the generation of pancreatic neuropathy and pain in PCa.
T-020. Chemokine ligand CXCL16 is an indicator of infected necrosis in necrotizing pancreatitis Uwe A. Wittel a, Andrea I. Schmidt a, Pauli Puolakkainen b, Ulrich Hopt a, €npa €a €b Leena Kyla €tsklinik Freiburg, Department of General- and Visceral Universita Surgery, Germany b Helsinki University Central Hospital, Department of Surgery, Finland a
Background: When in necrotizing pancreatits the necrotic tissue gets infected, the infected, necrotic tissue needs to be removed. Unfortunately, in most cases bacterial infection can only be diagnosed by invasive methods. Aims: We wanted to identify a serum marker capable of detecting bacterial infection of pancreatic necrosis in patients with severe necrotizing pancreatitis. Materials & methods: Necrotizing taurocholate pancreatitis with sterile (SN) and infected necrosis (IN) was induced in mice. Serum samples were examined by antibody based protein array. The serum concentration of 6 canidate proteins was examined by sandwich ELISAs. Human samples from patients with mild pancreatitis (MP) and severe pancreatitis (SP) with and without infection of pancreatic necrosis were analyzed by sandwich ELISAs. Results: Protein arrays identified several proteins to be increased in infected necrosis. The increase of serum IFNgR1 und CCL17 was induced by the presence of pancreatitis or infection alone. TRANCE and CXCL16 showed a significant increase in animals with infected necrosis (TRANCE: SN 60.7±32.0, IN 163.4±62.7ng/ml, p<0.005; CXCL16 SN 524.9±56.9, IN 1200.4±233.8ng/ml; p<0.05). CXCL16 showed an increased concentration in patients with infected pancreatic necrosis (MP 2.78±0.27, SP 5.20±1.50, IN 7.40±0.83 ng/ml, p<0.001) while C-reactive protein did not show significant differences in our collective. Analysis of receiver operated characteristics indicated a good predictive value for CXCL16 detecting infection (AUC 0.844; p<0.0005) while C-reactive protein only had moderate predictive properties (AUC 0.704; p<0.05). Conclusion: By detecting the infection of pancreatic necrosis, serum CXCL16 is capable of identifying patients with severe necrotizing pancreatitis having a potential benefit from intervention.
T-021. L-glutamine transport and metabolism in the exocrine pancreas during acute pancreatitis Evelyne Kuster a, Rolf Graf b, François Verrey a, Simone Camargo a a b
University of Zurich, Institute of Physiology, Switzerland University Hospital Zurich, Department of Surgery, Switzerland
Background: Acute pancreatitis (AP) is a serious disease that results in the loss of acinar cells. The regeneration phase is marked by proliferation which requires an adaptation of nutrient transport to support
S55
proliferation and cell growth. During proliferating states, the demand for amino acids especially L-glutamine increases. Modulation of L-glutamine transport and its metabolism has been shown to impact on autophagy, cell growth and oxidative stress. The role of glutamine metabolism in the proliferating acinar cells during regeneration after AP is unknown. Aims: To characterise L-glutamine transport and metabolism during AP in isolated pancreatic acinar cells, using a mouse model. Materials & methods: AP was induced in male C57BL6/J mice by 12 hourly intraperitoneal cerulein injections (50ug/kg) and acinar cells were isolated 12, 24 respectively 72 hours after the first injection. Expression of L-glutamine transporters and metabolising enzymes were assessed by qPCR and Western blot analysis. Amino acid concentrations in serum and in acinar cells were determined by UPLC. Pancreatic tissue sections were subjected to immunofluorescence analysis. Results: We observed in our preliminary results that the concentration of free L-glutamine increases highly and rapidly in acinar cells after the induction of AP. RNA and Protein expression of the acinar glutamine transporter SNAT5 (Slc38a5) and the acinar isoform of glutaminase (Gls2) are impaired during AP. Conclusion: Transport and metabolism of L-glutamine in pancreatic acinar cells are altered during the acute and the regenerative processes of AP. These new insights might help in designing more effective nutritional support for AP patients.
T-022. Distinctive roles of unsaturated and saturated fatty acids in the pathogenesis of hyperlipidemic pancreatitis Yu-Ting Chang a, Ming-Chu Chang a, Chien-Chih Tung b, Jau-Min Wong a a Department of Internal Medicine, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taiwan b Department of Integrated Diagnostics & Therapeutics, National Taiwan University Hospital, Taiwan
Background: Hypertriglyceridemia (HTG) is the third frequent etiology of acute pancreatitis in Taiwan. It is difficult to explain why some patients experienced acute pancreatitis and why some patients with HTG seldom develop pancreatitis even with marked elevation of triglyceride. We hypothesized that the composition of saturated and unsaturated fatty acids may influence the susceptibility to develop acute pancreatitis in HTG patients. Aims: To investigate the hypothesis that the composition of triglyceride may influence the susceptibility to develop acute pancreatitis. Materials & methods: Primary pancreatic acinar cell culture were treated with low and high concentrations of different saturated and unsaturated fatty acids. Cytosolic Ca2+ signal change and expression of protein kinase C (PKC) in acinar cells were measured after treatment. Results: Unsaturated fatty acids, including Oleic acid, Linoleic acid, Palmitoleic acid, DHA, and arachidonic acid in high concentration induced the persistent rise of cytosolic Ca2+ concentration in acinar cell. Unsaturated fatty acids in low concentration and saturated fatty acids, including Palmitic acid and Stearic acid, and triglyceride in low and high concentrations could not induce the rise of Ca2+ concentration in acinar cell. Unsaturated fatty acids instead of saturated fatty acids induced intra-acinar cell trypsin activation and cell damage and more PKC expression. Conclusion: Triglyceride itself could not induce the attack of acute pancreatitis. Only the ratio of unsaturated/saturated fatty acid high enough, the acinar cells become injured then pancreatitis developed. The unsaturated fatty acids may play a distinctive role in the pathogenesis of pancreatitis. The results explain that why clinically only a portion of HTG patients develop pancreatitis.
Abstracts / Pancreatology 14 (2014) S1eS129
Aims: To investigate the effects of LPS and hyperglycemia on PSC activation and effects of simvastatin on LPS induced PSC activation. Materials & methods: Primary cultures of rat PSCs were exposed to various concentrations of glucose and LPS with/without simvastatin. Quantification of proliferation was performed by Brd-U assay. PSC activation was assessed by expression of a-SMA and extracellular signal-regulated kinase (ERK) using Western blot. Results: LPS induced activation and proliferation of PSC. However, glucose did not affect PSC proliferation. The proliferative effect of LPS on PSC was not affected by glucose concentration in culture media. Simvastatin inhibited LPS induced activation and proliferation of PSC. The proliferative effect of LPS was mediated by activation of Erk 1/2 pathway which was effectively inhibited by simvastatin. Conclusion: This study shows that LPS is one of the activating factors toward PSC. Endotoxemia which is frequently encountered in the clinical settings of acute and chronic pancreatitis may act as a triggering factor for initiating and persisting pancreatic fibrosis. Simvastain could be a therapeutic agent for preventing pancreatic fibrosis.
T-017. Oxidative stress and proinflammatory role of pancreatic stellate cells in response to tobacco and alcohol ~ eiras-Alvarin ~ o a, María Luaces-Regueira a, J. Enrique Margarita Castin ~ oz b Domínguez-Mun a
Foundation for Research in Digestive Diseases, Spain University Hospital of Santiago de Compostela. Foundation for Research in Digestive Diseases, Spain b
Background: Smoking and alcohol are recognized risk factors for chronic pancreatitis (CP). Previous studies from our group showed that both toxics are associated with pancreatic fibrosis development mediated by pancreatic stellate cells (PSC) activation. This activation may be regulated by reactive oxygen species (ROS) production and perpetuated by cytokine secretion involved in the inflammatory response. Aims: To study the role of tobacco, as independent factor or associated with alcohol, on oxidative stress production and secretion of proinflammatory cytokines in PSC primary culture. Materials & methods: Isolated PSC from rat pancreas were exposed to tobacco alone (0.01mg/ml) or in combination of increasing concentrations of ethanol (5 to 50mM). ROS production was examined using 2’-7’-dichlorofluorescin diacetate (DCF-DA) and was detected by flow cytometry. Fractalkine secretion as proinflammatory cytokine was evaluated by ELISA. Results are expressed as mean±SEM. Data were analyzed by ANOVA. Results: Alcohol at 50mM alone (3.06±0.77, p¼0.008 vs negative control) or in combination with tobacco (2.68±0.49, p¼0.027 vs negative control) induced ROS production into PSC without a synergic effect of both toxics. Tobacco in combination with 50 mM ethanol induced fractalkine secretion at 48 hours (11.5±3.3 pg/mL vs 5±1.25 pg/mL negative control; p¼0.017). Conclusion: The association of alcohol and tobacco stimulates ROS production and fractalkine secretion in the PSC, thereby perpetuating the activated PSC phenotype. This fact explains the progression of pancreatic fibrosis in patients maintaining alcohol and smoking consumption, and represents the pathophysiological basis for a strict recommendation for drinking and smoking cessation in patients with chronic pancreatitis.
T-018. The role of heat shock protein 70 in pancreatic stellate cells Jong Jin Hyun, Jae Min Lee, Hyo Jung Kim, Jae Seon Kim, Hong Sik Lee, Chang Duck Kim Korea University College of Medicine, Department of Internal Medicine, South Korea Background: The role of heat shock protein 70 (hsp70) in acinar cells (acute pancreatitis) and ductal cells (pancreatic cancer) has been extensively studied. However, the role of hsp70 in pancreatic stellate cell (PSC), an important cell responsible for desmoplastic reaction, is less well understood. Aims: To investigate the role of hsp70 in PSC activation and proliferation. Materials & methods: PSCs were incubated at 42 C for 2hr and recovered at 37 C for 24hr in order to induce hsp70 expression. Cultured PSCs were treated with heat, PDGF, TGF-b, and LPS to measure a-SMA and hsp70 expression by Western blotting. Cell proliferation was measured by BrdU assay. Simvastatin and quercetin were used in order to inhibit PSC proliferation and hsp70 expression, respectively. Results: Overexpression of hsp70 did not affect cytokine induced aSMA expression. Hsp70 expression was significantly increased with PDGF and to a moderate degree with LPS, but not with TGF-b. Similarly, PSC proliferation was also significantly increased by PDGF and to a lesser degree by LPS, but TGF-b did not induce PSC proliferation. Simvastatin suppressed hsp70 expression and PSC proliferation induced by heat or PDGF. Quercetin completely inhibited PDGF-induced hsp70 expression and cell proliferation and partly inhibited heat-induced effects. However, heat preconditioning which induces hsp70 expression had no additional effect on PDGF induced cell proliferation. Conclusion: Hsp70 expression was closely related to cell proliferation in PSCs. Inhibition of hsp70 expression abolished or decreased the effect of PDGF and heat on cell proliferation. Therefore, modulation of hsp70 expression could be an effective therapeutic target for inhibition of pancreatic fibrosis.
T-019. Characterization of the nerve-stellate cell interactions in pancreatic cancer €ß, Ihsan Ekin Demir, Helmut Steffen Teller, Dominic Dischl, Rüdiger Go Friess, Güralp O. Ceyhan Chirurgische Klinik und Poliklinik, Pankreasforschungslabor, Klinikum rechts der Isar, TU München, Ismaninger Straße 22, D-81675, Germany Background: Pancreatic stellate cells (PSC) emerged in recent years as the main actor for the generation of pancreatic fibrosis in pancreatic cancer (PCa). Subsequent to their activation, PSC start to proliferate, migrate, and produce several extracellular matrix (ECM) components as well as cytokines. In this context, neural invasion and pancreatic neuroplasticity is most prominent in the desmoplastic areas. Aims: The present study aims at elucidating the characterisation of the interactions of nerves, carcinoma cells and PSC and the potential impact of PSC during the generation of neuropathic alterations in PCa. Materials & methods: PSC were isolated from Wistar rats and cultivated under hypoxia, stimulated with TGFß or left untreated as controls. After cell lysis, the expression of neurotrophic factors and their receptors (GFRa) was determined by Immunoblotting and by qRT-PCR. For neuroplasticity assays, dorsal root ganglia (DRG) were isolated from newborn
Abstracts / Pancreatology 14 (2014) S1eS129
Wistar rats and treated with supernatants of quiescent and activated PSC. Changes in neurite length, axonal branching, perikaryonal diameter and glial density were determined. Results: PSC produce neurotrophic factors as well as their receptors and alter the expression pattern of neurturin and artemin after activation towards their active forms, whereas the GFRa expression remains unchanged. After treatment of PSC with hypoxia or TGFß, PSC are activated. Cell culture supernatants of activated PSC lead to an increased neurite and glial density in isolated DRG. Conclusion: Activated PSC alter their expression pattern of neurotrophic factors, influence neuroplasticity of isolated DRG and therefore may play a seminal role in the generation of pancreatic neuropathy and pain in PCa.
T-020. Chemokine ligand CXCL16 is an indicator of infected necrosis in necrotizing pancreatitis Uwe A. Wittel a, Andrea I. Schmidt a, Pauli Puolakkainen b, Ulrich Hopt a, €npa €a €b Leena Kyla €tsklinik Freiburg, Department of General- and Visceral Universita Surgery, Germany b Helsinki University Central Hospital, Department of Surgery, Finland a
Background: When in necrotizing pancreatits the necrotic tissue gets infected, the infected, necrotic tissue needs to be removed. Unfortunately, in most cases bacterial infection can only be diagnosed by invasive methods. Aims: We wanted to identify a serum marker capable of detecting bacterial infection of pancreatic necrosis in patients with severe necrotizing pancreatitis. Materials & methods: Necrotizing taurocholate pancreatitis with sterile (SN) and infected necrosis (IN) was induced in mice. Serum samples were examined by antibody based protein array. The serum concentration of 6 canidate proteins was examined by sandwich ELISAs. Human samples from patients with mild pancreatitis (MP) and severe pancreatitis (SP) with and without infection of pancreatic necrosis were analyzed by sandwich ELISAs. Results: Protein arrays identified several proteins to be increased in infected necrosis. The increase of serum IFNgR1 und CCL17 was induced by the presence of pancreatitis or infection alone. TRANCE and CXCL16 showed a significant increase in animals with infected necrosis (TRANCE: SN 60.7±32.0, IN 163.4±62.7ng/ml, p<0.005; CXCL16 SN 524.9±56.9, IN 1200.4±233.8ng/ml; p<0.05). CXCL16 showed an increased concentration in patients with infected pancreatic necrosis (MP 2.78±0.27, SP 5.20±1.50, IN 7.40±0.83 ng/ml, p<0.001) while C-reactive protein did not show significant differences in our collective. Analysis of receiver operated characteristics indicated a good predictive value for CXCL16 detecting infection (AUC 0.844; p<0.0005) while C-reactive protein only had moderate predictive properties (AUC 0.704; p<0.05). Conclusion: By detecting the infection of pancreatic necrosis, serum CXCL16 is capable of identifying patients with severe necrotizing pancreatitis having a potential benefit from intervention.
T-021. L-glutamine transport and metabolism in the exocrine pancreas during acute pancreatitis Evelyne Kuster a, Rolf Graf b, François Verrey a, Simone Camargo a a b
University of Zurich, Institute of Physiology, Switzerland University Hospital Zurich, Department of Surgery, Switzerland
Background: Acute pancreatitis (AP) is a serious disease that results in the loss of acinar cells. The regeneration phase is marked by proliferation which requires an adaptation of nutrient transport to support
S55
proliferation and cell growth. During proliferating states, the demand for amino acids especially L-glutamine increases. Modulation of L-glutamine transport and its metabolism has been shown to impact on autophagy, cell growth and oxidative stress. The role of glutamine metabolism in the proliferating acinar cells during regeneration after AP is unknown. Aims: To characterise L-glutamine transport and metabolism during AP in isolated pancreatic acinar cells, using a mouse model. Materials & methods: AP was induced in male C57BL6/J mice by 12 hourly intraperitoneal cerulein injections (50ug/kg) and acinar cells were isolated 12, 24 respectively 72 hours after the first injection. Expression of L-glutamine transporters and metabolising enzymes were assessed by qPCR and Western blot analysis. Amino acid concentrations in serum and in acinar cells were determined by UPLC. Pancreatic tissue sections were subjected to immunofluorescence analysis. Results: We observed in our preliminary results that the concentration of free L-glutamine increases highly and rapidly in acinar cells after the induction of AP. RNA and Protein expression of the acinar glutamine transporter SNAT5 (Slc38a5) and the acinar isoform of glutaminase (Gls2) are impaired during AP. Conclusion: Transport and metabolism of L-glutamine in pancreatic acinar cells are altered during the acute and the regenerative processes of AP. These new insights might help in designing more effective nutritional support for AP patients.
T-022. Distinctive roles of unsaturated and saturated fatty acids in the pathogenesis of hyperlipidemic pancreatitis Yu-Ting Chang a, Ming-Chu Chang a, Chien-Chih Tung b, Jau-Min Wong a a Department of Internal Medicine, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taiwan b Department of Integrated Diagnostics & Therapeutics, National Taiwan University Hospital, Taiwan
Background: Hypertriglyceridemia (HTG) is the third frequent etiology of acute pancreatitis in Taiwan. It is difficult to explain why some patients experienced acute pancreatitis and why some patients with HTG seldom develop pancreatitis even with marked elevation of triglyceride. We hypothesized that the composition of saturated and unsaturated fatty acids may influence the susceptibility to develop acute pancreatitis in HTG patients. Aims: To investigate the hypothesis that the composition of triglyceride may influence the susceptibility to develop acute pancreatitis. Materials & methods: Primary pancreatic acinar cell culture were treated with low and high concentrations of different saturated and unsaturated fatty acids. Cytosolic Ca2+ signal change and expression of protein kinase C (PKC) in acinar cells were measured after treatment. Results: Unsaturated fatty acids, including Oleic acid, Linoleic acid, Palmitoleic acid, DHA, and arachidonic acid in high concentration induced the persistent rise of cytosolic Ca2+ concentration in acinar cell. Unsaturated fatty acids in low concentration and saturated fatty acids, including Palmitic acid and Stearic acid, and triglyceride in low and high concentrations could not induce the rise of Ca2+ concentration in acinar cell. Unsaturated fatty acids instead of saturated fatty acids induced intra-acinar cell trypsin activation and cell damage and more PKC expression. Conclusion: Triglyceride itself could not induce the attack of acute pancreatitis. Only the ratio of unsaturated/saturated fatty acid high enough, the acinar cells become injured then pancreatitis developed. The unsaturated fatty acids may play a distinctive role in the pathogenesis of pancreatitis. The results explain that why clinically only a portion of HTG patients develop pancreatitis.