Cardiovascular disease and resuscitated septic shock lead to the downregulation of the H2S-producing enzyme cystathionine-γ-lyase in the porcine coronary artery.
BACKGROUND
Downregulation of the hydrogen sulfide (H2S)-producing enzymes cystathionine-γ-lyase (CSE), cystathionine-β-synthase (CBS), and/or 3-mercaptopyruvate sulfurtransferase (3-MST) is associated with chronic cardiovascular pathologies. Nevertheless, equivocal data are available on both the expression and function of these enzymes in coronary arteries (CA). We recently reported that atherosclerotic pigs subjected to sepsis developed impaired cardiac function, which coincided with decreased myocardial CSE expression and increased nitrotyrosine formation. To define the endogenous source(s) of H2S in the CA, we studied the expression of CBS, CSE, or 3-MST in the CA of pigs subjected to septic shock with/without pre-existing cardiovascular co-morbidity.


METHODS
Anesthetized and instrumented FBM "familial hypercholesterolemia Bretoncelles Meishan" pigs with high-fat diet-induced hypercholesterolemia and atherosclerosis were subjected to polymicrobial septic shock, or sham procedure, and subsequent intensive care therapy for 24 h. Young German domestic pigs were used as naïve controls. CSE, CBS, 3-MST, HO-1, eNOS, and nitrotyrosine expression was quantified by immunohistochemistry of formalin-fixed paraffin sections.


RESULTS
FBM pigs, in the absence of septic shock, showed decreased CSE expression in the media. This decrease became more pronounced after sepsis. The expression pattern of HO-1 resembled the pattern of CSE expression. CBS protein was not detected in the media of any of the CA examined but was localized to the adventitia and only in the atheromatous plaques containing foam cells of the CA, in regions that also displayed abundant nitrotyrosine formation. The CBS expression in the adventitia was not associated with nitrotyrosine formation. 3-MST expression was not found in any of the CA samples.


CONCLUSIONS
We hypothesize that (i) the reduced CSE expression in FBM pigs may contribute to their cardiovascular disease phenotype and moreover (ii) the further decrease in CA CSE expression in sepsis may contribute to the sepsis-associated cardiac dysfunction.
Universitätsklinik Ulm, Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Helmholtzstrasse 8, 89081, Ulm, Germany.
Tamara
T
Merz
Universitätsklinik Ulm, Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Helmholtzstrasse 8, 89081, Ulm, Germany.
Tatjana
T
Stenzel
Universitätsklinik Ulm, Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Helmholtzstrasse 8, 89081, Ulm, Germany.|Universitätsklinik Ulm, Klinik für Anästhesiologie, Albert-Einstein-Allee 23, 89081, Ulm, Germany.
Benedikt
B
Nußbaum
Universitätsklinik Ulm, Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Helmholtzstrasse 8, 89081, Ulm, Germany.|Universitätsklinik Ulm, Klinik für Anästhesiologie, Albert-Einstein-Allee 23, 89081, Ulm, Germany.
Martin
M
Wepler
Department of Anesthesiology, The University of Texas Medical Branch at Galveston, 601 Harborside Drive, Galveston, TX, 77555, USA.
Csaba
C
Szabo
Department of Biology, Laurentian University, Sudbury, ON, Canada.
Rui
R
Wang
Universitätsklinik Ulm, Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Helmholtzstrasse 8, 89081, Ulm, Germany.
Peter
P
Radermacher
Universitätsklinik Ulm, Institut für Anästhesiologische Pathophysiologie und Verfahrensentwicklung, Helmholtzstrasse 8, 89081, Ulm, Germany. oscar.mccook@uni-ulm.de.|Institute of Anesthesiological Pathophysiology and Process Engineering, University Medical School, Helmholtzstrasse 8-1, 89081, Ulm, Germany. oscar.mccook@uni-ulm.de.
Oscar
http://orcid.org/0000-0001-7879-7695
O
McCook
Blood vessels; Endothelial NO synthase; Oxidative stress; Peroxynitrite; Shock