The diaphragm is better protected from oxidative stress than hindlimb skeletal muscle during CLP-induced sepsis.
OBJECTIVE
The aim of this study was to determine whether non-lethal sepsis induced by cecal ligation and puncture (CLP) modulates oxidative damage and enzymatic antioxidant defenses in diaphragm and hindlimb skeletal muscles (soleus and Extensor Digitorus Longus (EDL)).


METHODS
Female Wistar rats were divided into four experimental groups: (1) control animals, (2) animals sacrificed 2 hours or (3) 7 days after CLP, and (4) sham-operated animals. At the end of the experimental procedure, EDL, soleus, and diaphragm muscles were harvested and 4-hydroxynonenal (HNE)-protein adducts and protein carbonyl contents were examined in relation to superoxide dismutase and catalase expression and activities.


RESULTS
We observed that both non-respiratory oxidative (i.e. soleus) and glycolytic skeletal muscles (i.e. EDL) are more susceptible to sepsis-induced oxidative stress than diaphragm, as attested by an increase in 4-HNE protein adducts and carbonylated proteins after 2 hours of CLP only in soleus and EDL.


CONCLUSIONS
These differences could be explained by higher basal enzymatic antioxidant activities in diaphragm compared to hindlimb skeletal muscles. Together, these results demonstrate that diaphragm is better protected from oxidative stress than hindlimb skeletal muscles during CLP-induced sepsis.
a Physiology Department EA1274, UFR Médecine et Sciences de la Santé , Université de Bretagne Occidentale , Brest , France.
Hélène
H
Talarmin
b "Movement Sport and Health Sciences" Laboratory EA1274 , University Rennes 2-ENS Rennes , Bruz , France.
Frédéric
F
Derbré
b "Movement Sport and Health Sciences" Laboratory EA1274 , University Rennes 2-ENS Rennes , Bruz , France.
Luz
L
Lefeuvre-Orfila
a Physiology Department EA1274, UFR Médecine et Sciences de la Santé , Université de Bretagne Occidentale , Brest , France.
Karelle
K
Léon
a Physiology Department EA1274, UFR Médecine et Sciences de la Santé , Université de Bretagne Occidentale , Brest , France.
Mickaël
M
Droguet
a Physiology Department EA1274, UFR Médecine et Sciences de la Santé , Université de Bretagne Occidentale , Brest , France.
Jean-Pierre
JP
Pennec
a Physiology Department EA1274, UFR Médecine et Sciences de la Santé , Université de Bretagne Occidentale , Brest , France.
Marie-Agnès
MA
Giroux-Metgès
D000447:Aldehydes / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D002432:Cecum / Q000601:surgery; D003964:Diaphragm; D005260:Female; D006614:Hindlimb; D008026:Ligation; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000503:physiopathology; D018384:Oxidative Stress; D050050:Protein Carbonylation; D017208:Rats, Wistar; D018805:Sepsis / Q000378:metabolism / Q000503:physiopathology*; D013482:Superoxide Dismutase / Q000378:metabolism
D000447:Aldehydes; D000975:Antioxidants; D002374:Catalase; D013482:Superoxide Dismutase; C027576:4-hydroxy-2-nonenal
4-HNE; antioxidant enzymes; diaphragm; protein carbonylation; soleus