ShRNA-mediated gene silencing of lipoprotein lipase improves insulin sensitivity in L6 skeletal muscle cells
- Resource Type
- Authors
- Jheem D. Medh; Majib Jan
- Source
- Biochemical and Biophysical Research Communications. 462:33-37
- Subject
- medicine.medical_specialty
Glucose uptake
medicine.medical_treatment
Muscle Fibers, Skeletal
Biophysics
Gene Expression
Biochemistry
Article
Cell Line
Internal medicine
medicine
Animals
Hypoglycemic Agents
Insulin
Myocyte
RNA, Small Interfering
Glycogen synthase
Molecular Biology
Lipoprotein lipase
biology
Reverse Transcriptase Polymerase Chain Reaction
digestive, oral, and skin physiology
nutritional and metabolic diseases
Skeletal muscle
Cell Biology
Transfection
Actins
Rats
Lipoprotein Lipase
Glucose
medicine.anatomical_structure
Endocrinology
Cell culture
biology.protein
RNA Interference
lipids (amino acids, peptides, and proteins)
Insulin Resistance
Oxidation-Reduction
Glycogen
Oleic Acid
- Language
- ISSN
- 0006-291X
In previous studies, we demonstrated that down-regulation of lipoprotein lipase in L6 muscle cells increased insulin-stimulated glucose uptake. In the current study, we used RNA interference technology to silence the LPL gene in L6 cells and generate a LPL-knock-down (LPL-KD) cell line. ShRNA transfected cells showed a 88% reduction in the level of LPL expression. The metabolic response to insulin was compared in wild-type (WT) and LPL-KD cells. Insulin-stimulated glycogen synthesis and glucose oxidation were respectively, 2.4-fold and 2.6-fold greater in LPL-KD cells compared to WT cells. Oxidation of oleic acid was reduced by 50% in LPL-KD cells compared to WT cells even in the absence of insulin. The contribution of LPL in regulating fuel metabolism was confirmed by adding back purified LPL to the culture media of LPL-KD cells. The presence of 10 µg/mL LPL resulted in LPL-KD cells reverting back to lower glycogen synthesis and glucose oxidation and increased fatty acid oxidation. Thus, LPL depletion appeared to mimic the action of insulin. These finding suggests an inverse correlation between muscle LPL levels and insulin-stimulated fuel homeostasis.