5 research outputs found
Hydrogen sulfide formation in experimental model of acute pancreatitis
Acute pancreatitis (AP) is a disease defined as acute or
chronic inflammatory process of the pancreas characterized by premature activation of digestive enzymes
within the pancreatic acinar cells and causing pancreatic
auto-digestion. In mammalian tissues, H2S is synthesized
endogenously from L-cysteine in regulated enzymatic
pathways catalyzed by pyridoxal phosphate-dependent
enzymes: cystathionine beta-synthase (CBS), gammacystathionase (CTH) and cysteine aminotransferase
(CAT) coupled with 3-mercaptopyruvate sulfurtransferase (MPST). In the mitochondria, hydrogen sulfide is
oxidized to sulfite, which is then converted to thiosulfate
(a sulfane sulfur-containing compound) by thiosulfate
sulfurtransferase (rhodanese; TST). Activity and expression of CBS, CTH, MPST, and TST have been determined
in vivo in pancreas of the control rats, rats with acute
pancreatitis and a sham group. Levels of low-molecular
sulfur compounds, such as the reduced and oxidized
glutathione, cysteine, cystine and cystathionine, were
also determined. This study revealed a significant role of
MPST in H2S metabolism in the pancreas. Stress caused
by the surgery (sham group) and AP cause a decrease in
H2S production associated with a decrease in MPST activity and expression. Markedly higher level of cysteine
in the AP pancreas may be caused by a reduced rate of
cysteine consumption in a reaction catalyzed by MPST,
but it can also be a sign of proteolytic processes occurring in the changed tissu