Thermal stress-induced HSP70 mediates protection against intrapancreatic trypsinogen activation and acute pancreatitis in rats

Gastroenterology. 2002 Jan;122(1):156-65. doi: 10.1053/gast.2002.30314.

Abstract

Background & aims: Prior thermal stress induces heat shock protein 70 (HSP70) expression in the pancreas and protects against secretagogue-induced pancreatitis, but it is not clear that this thermal stress-induced protection is actually mediated by HSP70 since thermal stress may have other, non-HSP related, effects.

Methods: In the present study, we have administered antisense (AS) oligonucleotides, which prevent pancreatic expression of HSP70 to rats, in vivo, to evaluate this issue. In a separate series of experiments, designed to examine the role of pancreatitis-induced HSP70 expression in modulating the severity of pancreatitis, rats not subjected to prior thermal stress were given AS-HSP70 before cerulein administration, and trypsinogen activation as well as the severity of pancreatitis were evaluated.

Results: Hyperthermia induced HSP70 expression, prevented intrapancreatic trypsinogen activation, and protected against cerulein-induced pancreatitis. Administration of AS-HSP70 but not sense-HSP70 reduced the thermal stress-induced HSP70 expression, restored the ability of supramaximal cerulein stimulation to cause intrapancreatic trypsinogen activation, and abolished the protective effect of prior thermal stress against pancreatitis. In non-thermally stressed animals, pretreatment with AS-HSP70 before the induction of pancreatitis exacerbated all the parameters associated with pancreatitis.

Conclusions: These findings lead us to conclude that HSP70 induction, rather than some other thermal stress-related phenomenon, mediates the thermal stress-induced protection against pancreatitis and that it protects against pancreatitis by preventing intrapancreatic activation of trypsinogen. The worsening of pancreatitis, which occurs when non-thermally stressed animals are given AS-HSP70 before cerulein, suggests that cerulein-induced HSP70 expression in nontreated animals acts to limit the severity of pancreatitis.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acute Disease
  • Animals
  • Ceruletide
  • Gene Expression Regulation / physiology
  • HSP70 Heat-Shock Proteins / genetics*
  • HSP70 Heat-Shock Proteins / metabolism
  • Heat Stress Disorders / metabolism*
  • Oligonucleotides, Antisense / pharmacology
  • Pancreatitis / chemically induced
  • Pancreatitis / metabolism*
  • Pancreatitis / pathology
  • Rats
  • Rats, Wistar
  • Stress, Physiological / metabolism
  • Trypsinogen / metabolism*

Substances

  • HSP70 Heat-Shock Proteins
  • Oligonucleotides, Antisense
  • Ceruletide
  • Trypsinogen