Cardiolipin linoleic acid content and mitochondrial cytochrome c oxidase activity are associated in rat skeletal muscle.
Cardiolipin (CL) is an inner-mitochondrial membrane phospholipid that is important for optimal mitochondrial function. Specifically, CL and CL linoleic (18:2ω6) content are known to be positively associated with cytochrome c oxidase (COX) activity. However, this association has not been examined in skeletal muscle. In this study, rats were fed high-fat diets with a naturally occurring gradient in linoleic acid (coconut oil [CO], 5.8%; flaxseed oil [FO], 13.2%; safflower oil [SO], 75.1%) in an attempt to alter both mitochondrial CL fatty acyl composition and COX activity in rat mixed hind-limb muscle. In general, mitochondrial membrane lipid composition was fairly resistant to dietary treatments as only modest changes in fatty acyl composition were detected in CL and other major mitochondrial phospholipids such as phosphatidylcholine (PC) and phosphatidylethanolamine (PE). As a result of this resistance, CL 18:2ω6 content was not different between the dietary groups. Consistent with the lack of changes in CL 18:2ω6 content, mitochondrial COX activity was also not different between the dietary groups. However, correlational analysis using data obtained from rats across the dietary groups showed a significant relationship (p = 0.009, R(2) = 0.21). Specifically, our results suggest that CL 18:2ω6 content may positively influence mitochondrial COX activity thereby making this lipid molecule a potential factor related to mitochondrial health and function in skeletal muscle.
Centre for Bone and Muscle Health, Department of Health Sciences, Faculty of Applied Health Sciences, Brock University, 500 Glenridge Ave., St. Catharines, ON L2S 3A, Canada.
Val Andrew
VA
Fajardo
Centre for Bone and Muscle Health, Department of Health Sciences, Faculty of Applied Health Sciences, Brock University, 500 Glenridge Ave., St. Catharines, ON L2S 3A, Canada.
Lauren
L
McMeekin
Centre for Bone and Muscle Health, Department of Health Sciences, Faculty of Applied Health Sciences, Brock University, 500 Glenridge Ave., St. Catharines, ON L2S 3A, Canada.
Caitlin
C
Saint
Centre for Bone and Muscle Health, Department of Health Sciences, Faculty of Applied Health Sciences, Brock University, 500 Glenridge Ave., St. Catharines, ON L2S 3A, Canada. Electronic address: pleblanc@brocku.ca.
Paul J
PJ
LeBlanc
D000818:Animals; D002308:Cardiolipins / Q000378:metabolism*; D059305:Diet, High-Fat / Q000379:methods; D004041:Dietary Fats / Q000378:metabolism*; D003576:Electron Transport Complex IV / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000502:physiology*; D019787:Linoleic Acid / Q000378:metabolism; D008931:Mitochondria, Muscle / Q000201:enzymology*; D018482:Muscle, Skeletal / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
D002308:Cardiolipins; D004041:Dietary Fats; D019787:Linoleic Acid; D003576:Electron Transport Complex IV
Cardiolipin; Cytochrome c oxidase; High fat diet; Linoleic acid; Skeletal muscle mitochondria