Stimulation of stellate cells by injured acinar cells: a model of acute pancreatitis induced by alcohol and fat (VLDL).
Mechanisms leading to acute pancreatitis after a fat-enriched meal combined with excess alcohol are incompletely understood. We have studied the effects of alcohol and fat (VLDL) on pancreatic acinar cell (PAC) function, oxidative stress, and repair mechanisms by pancreatic stellate cells (PSC) leading to fibrogenesis. To do so, PAC (rat) were isolated and cultured up to 24 h. Ethanol and/or VLDL were added to PAC. We measured PAC function (amylase, lipase), injury (lactic dehydrogenase), apoptosis (TUNEL, Apo2.7, annexin V binding), oxidative stress, and lipid peroxidation (conjugated dienes, malondialdehyde, chemoluminescence); we also measured PSC proliferation (bromodeoxyuridine incorporation), matrix synthesis (immunofluorescence of collagens and fibronectin, fibronectin immunoassay), and fatty acids in PAC supernatants (gas chromatography). Within 6 h, cultured PAC degraded and hydrolyzed VLDL completely. VLDL alone (50 microg/ml) and in combination with alcohol (0.2, 0.5, and 1% vol/vol) induced PAC injury (LDL, amylase, and lipase release) within 2 h through generation of oxidative stress. Depending on the dose of VLDL and alcohol, apoptosis and/or necrosis were induced. Antioxidants (Trolox, Probucol) reduced the cytotoxic effect of alcohol and VLDL. Supernatants of alcohol/VLDL-treated PAC stimulated stellate cell proliferation and extracellular matrix synthesis. We concluded that, in the presence of lipoproteins, alcohol induces acinar cell injury. Our results provide a biochemical pathway for the clinical observation that a fat-enriched meal combined with excess alcohol consumption can induce acinar cell injury (acute pancreatitis) followed by repair mechanisms (proliferation and increased matrix synthesis in PSC).
Siech
Marco
M
Dept. of General and Vascular Surgery, Ostalb-Klinikum Aalen, Germany. marco.siech@ostalb-klinikum.de
Zhou
Zhengfei
Z
Zhou
Shaoxia
S
Bair
Bernd
B
Alt
Andreas
A
Hamm
Stefan
S
Gross
Hans
H
Mayer
Jens
J
Beger
Hans G
HG
Tian
Xiaodong
X
Kornmann
Marko
M
Bachem
Max G
MG
D000208:Acute Disease; D000681:Amylases / Q000378:metabolism; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D000431:Ethanol / Q000633:toxicity*; D005109:Extracellular Matrix / Q000378:metabolism*; D005355:Fibrosis; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008049:Lipase / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008079:Lipoproteins, VLDL / Q000378:metabolism / Q000633:toxicity*; D018384:Oxidative Stress / Q000187:drug effects; D046790:Pancreas, Exocrine / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D010195:Pancreatitis / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
D008079:Lipoproteins, VLDL; D000431:Ethanol; D007770:L-Lactate Dehydrogenase; D008049:Lipase; D000681:Amylases