Early Myocardial Dysfunction is Not Caused by Mitochondrial Abnormalities in a Rat Model of Peritonitis

Lonneke Smeding*, Willem J. van der Laarse, Toke A. van Veelen, Regis R. Lamberts, Hans W. M. Niessen, Martin C. J. Kneyber, A. B. Johan Groeneveld, Frans B. Plotz

*Bijbehorende auteur voor dit werk

OnderzoeksoutputAcademicpeer review

8 Citaten (Scopus)

Samenvatting

Background. Patients with complicated intra-abdominal infections are prone to develop multiple organ failure, including myocardial dysfunction. We hypothesized that early dysfunction during sepsis is associated with inflammation, mitochondrial injury, impaired mitochondrial function, and activation of mitochondrial biogenesis.

Materials and Methods. Rats received lipopolysaccharide (LPS, n = 11) intraperitoneally. Healthy rats (n = 6) served as controls. Myocardial function was measured ex vivo in an isolated Langendorff-perfused heart set-up. Myocardial vascular cell adhesion molecule-1 (VCAM-1) expression was determined by immunofluorescence microscopy. Cytochrome c release and cytochrome c oxidase (COX IV) activity were measured by immunohistochemistry and enzyme histochemistry, respectively. Protein expression of tumor necrosis factor-alpha (TNF-alpha), B-cell lymphoma (Bcl)-2, peroxisome proliferator activated receptor gamma cofactor 1 alpha (PGC-1 alpha), and mitochondrial transcription factor A (TFAM) were analyzed by Western blot technique. Mitochondria were studied by electron microscopy.

Results. Two hours after LPS injection, developed pressure had decreased and after 4 h myocardial contractility (DdP/dt) and relaxation (-dP/dt) also had decreased. TNF-alpha protein expression was increased after 2 h and returned to normal at 4 h, whereas after 4 h VCAM-1expression was higher in LPS-treated animals. At 2 h a substrate-dependent increase in COXIV-activity was seen, but no mitochondrial damage occurred as cytochrome c release, COX IV activity and Bcl-2, PGC-1 alpha or TFAM expression were not changed. Electron microscopy did not reveal differences in myocardial mitochondrial characteristics between LPS-treated and control rats.

Conclusions. Early myocardial dysfunction in sepsis is associated with myocardial inflammation but not with mitochondrial injury, impaired mitochondrial function, or activated mitochondrial biogenesis. (C) 2012 Elsevier Inc. All rights reserved.

Originele taal-2English
Pagina's (van-tot)178-184
Aantal pagina's7
TijdschriftJournal of Surgical Research
Volume176
Nummer van het tijdschrift1
DOI's
StatusPublished - jul-2012

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