L-carnitine stimulates lipolysis via induction of the lipolytic gene expression and suppression of the adipogenic gene expression in 3T3-L1 adipocytes.
We investigated the lipolytic effects of L-carnitine in 3T3-L1 adipocytes. L-carnitine at 10-S100 nM suppressed lipid accumulation. The release of glycerol and free fatty acid into the medium was significantly increased by 1.5- and 1.7- fold, respectively, by the addition of 100 nM L-carnitine compared with the control (P < .05). The mRNA levels of hormone-sensitive lipase, carnitine palmitoyltransferase I-a, and acyl-coenzyme A oxidase, all of which participate in lipid catabolism, were increased in the presence of 100 nM L-carnitine by 2.8-, 2.2-, and 1.6-fold, respectively (P < .05). However, the expression of peroxisome proliferator-activated receptor-gamma and adipose-specific fatty acid-binding protein, which are involved in adipogenesis, were down-regulated by L-carnitine in 3T3-L1 adipocytes (P < .05). These results suggest an anti-obesity action of L-carnitine. L-carnitine may modulate lipid metabolism by stimulation of lipolysis and beta-oxidation accompanied by corresponding changes in gene expression and suppression of adipogenic gene expression.
Lee
Mak-Soon
MS
Department of Food and Nutritional Sciences, Ewha Womans University, Sudaemun-Ku, Seoul, Republic of Korea.
Lee
Hyun-Jung
HJ
Lee
Hyun-Sook
HS
Kim
Yangha
Y
D041721:3T3-L1 Cells; D042962:Acyl-CoA Oxidase / Q000235:genetics; D017667:Adipocytes / Q000378:metabolism*; D050156:Adipogenesis / Q000187:drug effects / Q000235:genetics*; D000818:Animals; D002331:Carnitine / Q000494:pharmacology*; D002334:Carnitine O-Palmitoyltransferase / Q000235:genetics; D050556:Fatty Acid-Binding Proteins / Q000235:genetics; D015870:Gene Expression / Q000187:drug effects*; D008066:Lipolysis / Q000187:drug effects / Q000235:genetics*; D051379:Mice; D047495:PPAR gamma / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D002787:Sterol Esterase / Q000235:genetics
D050556:Fatty Acid-Binding Proteins; D047495:PPAR gamma; D012333:RNA, Messenger; D042962:Acyl-CoA Oxidase; D002334:Carnitine O-Palmitoyltransferase; D002787:Sterol Esterase; D002331:Carnitine