J Korean Diabetes Assoc.  2007 May;31(3):230-235. 10.4093/jkda.2007.31.3.230.

Effects of Lovastatin on Free Fatty Acid Oxidation in Cultured L6 Rat Skeletal Muscle Cells

• Kim DL
• Song KH
• Kim HR
• Kim SK

• KMID: 1523011
• DOI: http://doi.org/10.4093/jkda.2007.31.3.230

Abstract

BACKGROUND: Recent clinical studies suggest that statins improve insulin resistance and glucose metabolism in patients with metabolic syndrome and type 2 diabetes. To evaluate the possible mechanism of this action, we measured free fatty acid oxidation in cultured L6 rat skeletal muscle cell line.
METHODS
Cultured L6 myotubes were treated with or without lovastatin (1, 5, 20 micrometer) for 24 hours or 48 hours and palmitate oxidation was measured. We also measured protein concentration of the cells.
RESULTS
Lovastain increased palmitate oxidation in dose and time dependent manner in L6 myotubes (24 hr; 1 micrometer 119.2 +/- 11.9% of control, 5 micrometer 140.9 +/- 8.1%, 20 micrometer 150 +/- 5%, P = 0.05 vs control, respectively, 48 hr 1 micrometer 120.9 +/- 14.5%, 5 micrometer 176.6 +/- 28.2%, 20 micrometer 196.0 +/- 19.9%, P < 0.01 vs control, respectively). However, lovastatin decreased total cellular protein (24 hr: 1 micrometer 89.2 +/- 6.1% of control, 5 micrometer 79.3 +/- 7.6%, 20 micrometer 65.4 +/- 4.2%, P = 0.05 vs control, respectively, 48 hr: 1 micrometer 81.7 +/- 5.1%, 5 micrometer 58.6 +/- 11.9%, 20 micrometer 48.1 +/- 6.9%, P < 0.01 vs control, respectively).
CONCLUSION
Lovastatin increased skeletal muscle free fatty acid oxidation in L6 rat skeletal muscle cells. This would be one of the mechanisms which lovastatin improves insulin resistance.

Keyword

Fatty acid oxidation; Skeletal muscle; Statins

MeSH Terms

Animals
Cell Line
Glucose
Humans
Hydroxymethylglutaryl-CoA Reductase Inhibitors
Insulin Resistance
Lovastatin*
Metabolism
Muscle Fibers, Skeletal
Muscle, Skeletal*
Rats*
Glucose
Lovastatin

Figure

• 

  Fig. 1 Effects of lovastatin treatment on total cellular protein in cultured L6 cells. Fully differenciated myotubes were treated with lovastatin (0, 1, 5, 20 µM) for 24 hrs (n = 3) or 48 hrs (n = 8). Results were expressed as percentage of total concentration of protein in control cells for each individual set of cells. Data are mean ± SE. *P < 0.01 vs control value.

• 

  Fig. 2 Effects of lovastatin treatment on cell count in cultured L6 cells. Fully differenciated myotubes were treated with lovastatin (0, 1, 20 µM) for 24 hrs or 48 hrs (n = 3). Cell counts were expressed as percentage of total number of control cells for each individual set of cells. Data are mean ± SE.

• 

  Fig. 3 Effects of lovastatin treatment on palmitate oxidation activity in cultured L6 cells. Fully differenciated myotubes were treated with lovastatin (0, 1, 5, 20 µM) for 24 hrs (n = 3) or 48 hrs (n = 8). Myotubes were incubated with 3H-palmitate (5 mM final concentration) for 3 hr at 37℃. Products of oxidation were monitored as 3H2O released to the media. Results are mean ± SE. *P < 0.01 vs control value. †P < 0.01 vs value in 24 hr.

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