Lysophosphatidylserine regulates blood glucose by enhancing glucose transport in myotubes and adipocytes.
Lysophosphatidylserine (LPS) is known to have diverse cellular effects, but although LPS is present in many biological fluids, its in vivo effects have not been elucidated. In the present study, we investigated the effects of LPS on glucose metabolism in vivo, and how skeletal muscle cells respond to LPS stimulation. LPS enhanced glucose uptake in a dose- and time-dependent manner in L6 GLUT4myc myotubes, and this effect of LPS on glucose uptake was mediated by a Galpha(i) and PI 3-kinase dependent signal pathway. LPS increased the level of GLUT4 on the cell surface of L6 GLUT4myc myotubes, and enhanced glucose uptake in 3T3-L1 adipocytes. In line with its cellular functions, LPS lowered blood glucose levels in normal mice, while leaving insulin secretion unaffected. LPS also had a glucose-lowering effect in STZ-treated type 1 diabetic mice and in obese db/db type 2 diabetic mice. This study shows that LPS-stimulated glucose transport both in skeletal muscle cells and adipocytes, and significantly lowered blood glucose levels both in type 1 and 2 diabetic mice. Our results suggest that LPS is involved in the regulation of glucose homeostasis in skeletal muscle and adipose tissue.
Yea
Kyungmoo
K
Division of Molecular and Life Science, Pohang University of Science and Technology, Pohang, South Korea.
Kim
Jaeyoon
J
Lim
Seyoung
S
Kwon
Taewan
T
Park
Ho Seon
HS
Park
Kyong Soo
KS
Suh
Pann-Ghill
PG
Ryu
Sung Ho
SH
D016475:3T3 Cells; D017667:Adipocytes / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism*; D002460:Cell Line; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism; D003922:Diabetes Mellitus, Type 1 / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism; D006801:Humans; D008246:Lysophospholipids / Q000494:pharmacology / Q000502:physiology*; D051379:Mice; D008815:Mice, Inbred Strains; D018485:Muscle Fibers, Skeletal / Q000187:drug effects / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D051381:Rats
D001786:Blood Glucose; D008246:Lysophospholipids; C025059:lysophosphatidylserine; D019869:Phosphatidylinositol 3-Kinases