A high-capacity assay for activators of glucose incorporation into glycogen in L6 muscle cells.
Skeletal muscle is the major tissue responsible for insulin-stimulated glucose uptake and incorporation into glycogen. Skeletal muscle insulin resistance and the resulting postprandial hyperglycemia are hallmarks of non-insulin-dependent diabetes. Therefore, compounds that serve as insulin mimetics or insulin sensitizers in skeletal muscle may be effective in the treatment of diabetes. In order to identify such hypoglycemic agents, a novel assay for activators of glucose incorporation into glycogen has been developed utilizing differentiated L6 muscle cells in 96-well plates. We found that glucose incorporation occurs in a time- and concentration-dependent manner. It is inhibitable by phloretin, an inhibitor of glucose transport. Both insulin and the insulin-mimetic compound pervanadate activate L6 cell glucose incorporation in dose-responsive manners. We conclude that this assay should serve as a high-capacity screen to identify novel compounds that upregulate glucose anabolic metabolism in skeletal muscle. Such chemical entities may prove useful as antidiabetic agents.
Berger
J
J
Department of Molecular Endocrinology, Merck Research Laboratories, Rahway, New Jersey, 07065, USA. Joel_Berger@Merck.com
Hayes
N S
NS
D000818:Animals; D002460:Cell Line; D005947:Glucose / Q000378:metabolism*; D006003:Glycogen / Q000096:biosynthesis / Q000378:metabolism*; D007004:Hypoglycemic Agents / Q000494:pharmacology; D007328:Insulin / Q000737:chemistry / Q000494:pharmacology; D018716:Molecular Mimicry; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism*; D051381:Rats
D007004:Hypoglycemic Agents; D007328:Insulin; D006003:Glycogen; D005947:Glucose