Effects of trans MUFA from dairy and industrial sources on muscle mitochondrial function and insulin sensitivity.
Epidemiological studies suggest that chronic consumption of trans MUFA may alter muscle insulin sensitivity. The major sources of dietary trans MUFA (dairy fat vs. industrially hydrogenated oils) have different isomeric profiles and thus probably different metabolic consequences. These effects may involve alterations in muscle mitochondrial oxidative capacity, which may in turn promote insulin resistance if fatty acid oxidation is reduced. We report that in Wistar rats, an 8 week diet enriched (4% of energy intake) in either dairy, industrial, or control MUFA did not alter insulin and glucose responses to an intraperitoneal glucose tolerance test (1g/kg). In C2C12 myotubes, vaccenic and elaidic acids did not modify insulin sensitivity compared with oleic acid. Furthermore, the ex vivo total, mitochondrial and peroxisomal oxidation rates of [1-(14)C]oleic, vaccenic, and elaidic acids were similar in soleus and tibialis anterior rat muscle. Finally, an 8 week diet enriched in either dairy or industrial trans MUFA did not alter mitochondrial oxidative capacity in these two muscles compared with control MUFA but did induce a specific reduction in soleus mitochondrial ATP and superoxide anion production (P<0.01 vs. control). In conclusion, dietary trans MUFA of dairy or industrial origin have similar effects and do not impair muscle mitochondrial capacity and insulin sensitivity.
Tardy
Anne-Laure
AL
INRA, UMR 1019 Nutrition Humaine, F-63122 Saint Genès Champanelle, France.
Giraudet
Christophe
C
Rousset
Paulette
P
Rigaudière
Jean-Paul
JP
Laillet
Brigitte
B
Chalancon
Sandrine
S
Salles
Jérôme
J
Loreau
Olivier
O
Chardigny
Jean-Michel
JM
Morio
Béatrice
B
D000255:Adenosine Triphosphate / Q000096:biosynthesis; D000821:Animal Feed; D000818:Animals; D001823:Body Composition; D002460:Cell Line; D004041:Dietary Fats / Q000378:metabolism / Q000494:pharmacology*; D007221:Industry; D007328:Insulin / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism; D051336:Mitochondrial Membranes / Q000378:metabolism; D009132:Muscles / Q000187:drug effects* / Q000378:metabolism; D009821:Oils / Q000378:metabolism / Q000494:pharmacology*; D010084:Oxidation-Reduction; D051381:Rats; D017208:Rats, Wistar; D013481:Superoxides / Q000378:metabolism; D044242:Trans Fatty Acids / Q000378:metabolism / Q000494:pharmacology*
D004041:Dietary Fats; D007328:Insulin; D009821:Oils; D044242:Trans Fatty Acids; D013481:Superoxides; D000255:Adenosine Triphosphate