Cigarette smoke-induced differential expression of the genes involved in exocrine function of the rat pancreas.
OBJECTIVE
Little is known about the molecular and biological aspects of the epidemiological association between smoking and pancreatic pathology, such as chronic pancreatitis and pancreatic cancer. Recently, we reported that tobacco smoke exposure induced morphological alterations in the rat pancreas. Here, we have investigated the alterations in the expression of genes associated with exocrine pancreatic function and cellular differentiation upon exposure to cigarette smoke.


METHODS
Female rats were exposed to environmental smoke inhalation for 2 d/wk (70 min/d) for 12 weeks. The expression profiles of trypsinogen, pancreas-specific trypsin inhibitor, cholecystokinin A receptor, cystic fibrosis transmembrane conductance regulator (CFTR), carbonic anhydrase, and Muc1 and Muc4 mucins transcripts were analyzed by RNA slot blot analysis. Muc4 expression was also examined by immunohistochemistry.


RESULTS
Our data revealed that the ratio of trypsinogen to that of the protective pancreas-specific trypsin inhibitor was elevated upon cigarette smoke exposure. The expression of carbonic anhydrase and CFTR remained unaltered when inflammatory signs were not detected in histological examinations. On the other hand, when pancreatic inflammation was present, the levels of CFTR and carbonic anhydrase were increased, indicating ductal and/or centroacinar cell involvement. No changes in the expression of Muc1 and Muc4 mucins were observed.


CONCLUSIONS
Our data show that cigarette smoke exposure leads to an increased vulnerability to pancreatic self-digestion. Moreover, the concomitant involvement of pancreatic ducts occurs only when focal pancreatic inflammation is present.
Wittel
Uwe A
UA
Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha 68198-5870, USA.
Singh
Ajay P
AP
Henley
Brandon J
BJ
Andrianifahanana
Mahefatiana
M
Akhter
Mohammed P
MP
Cullen
Diane M
DM
Batra
Surinder K
SK
D000818:Animals; D002256:Carbonic Anhydrases / Q000235:genetics / Q000378:metabolism; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation; D009077:Mucins / Q000235:genetics / Q000378:metabolism; D046790:Pancreas, Exocrine / Q000378:metabolism* / Q000473:pathology; D010183:Pancreatic Ducts / Q000378:metabolism / Q000473:pathology; D010195:Pancreatitis / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D043886:Receptor, Cholecystokinin A / Q000235:genetics / Q000378:metabolism; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*; D014359:Trypsin Inhibitor, Kazal Pancreatic / Q000235:genetics / Q000378:metabolism; D014362:Trypsinogen / Q000235:genetics / Q000378:metabolism
D009077:Mucins; D012333:RNA, Messenger; D043886:Receptor, Cholecystokinin A; D014028:Tobacco Smoke Pollution; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D014359:Trypsin Inhibitor, Kazal Pancreatic; D014362:Trypsinogen; D002256:Carbonic Anhydrases