1,25-Dihydroxyvitamin D Induces Lipoprotein Lipase Expression in 3T3-L1 Cells in Association with Adipocyte Differentiation

Authors

Diane Vu, Cedars-Sinai Medical Center
John M. Ong, Cedars-Sinai Medical Center
Thomas L. Clemens, Cedars-Sinai Medical Center
Philip A. Kern, University of Kentucky

Abstract

1,25-dihydroxyvitamin D₃ [1,25-(OH)₂D₃] is known to modulate the development of hone and other mesenchymal cell types. Since osteoblasts and adipocytes are thought to arise in bone marrow from a common progenitor, this work examined the effects of 1,25-(OH)₂D₃ on adipocyte development, and in particular on the expression of lipoprotein lipase (LPL), which is an early marker for the differentiated adipocyte. 3T3-L1 preadipocytes were cultured in the presence of 1.25-(OH)₂D₃ (10^-9 to 10^-7 M) for up to 7 days. LPL activity was measured in the medium and cell extracts, and LPL messenger RNA levels were measured by Northern blotting. When compared to control cells, 10^-7 M 1,25-(OH)₂D₃ increased medium LPL activity by 2- to 3-fold and cellular LPL by 1.5-fold. Significant increases in medium and cellular LPL were observed at 10^-9 M and were maximal at 10^-7 M. Along with the increase in LPL activity, there was an increase in LPL messenger RNA by 2- fold at 5 days, and by 5-fold at 7 days. In addition to an increase in LPL, 1,25-(OH)₂D₃ increased expression of aP2, an adipocyte-specific marker associated with differentiation. After the addition of 1,25-(OH)₂D₃, there was a decrease in 3T3-L1 cell number, which is consistent with differentiation, and a decrease in vitamin D receptors. Finally, these cells developed a different morphology. 1,25-(OH)₂D₃-treated cells assumed a rounded appearance, although without detachment from the dish and without the degree of lipid accumulation usually associated with the addition of insulin, isobutylmethylxanthine, and dexamethasone. It is concluded that 1,25- (OH)₂D₃ induced LPL expression in 3T3-L1 cells through an induction of differentiation-dependent mechanism(s). These findings suggest an important role for 1,25-(OH)₂D₃ in normal adipocyte differentiation.

Document Type

Article

Publication Date

1996

Digital Object Identifier (DOI)

10.1210/endo.137.5.8612483

Repository Citation

Vu, Diane; Ong, John M.; Clemens, Thomas L.; and Kern, Philip A., "1,25-Dihydroxyvitamin D Induces Lipoprotein Lipase Expression in 3T3-L1 Cells in Association with Adipocyte Differentiation" (1996). Clinical and Translational Science Faculty Publications. 58.
https://uknowledge.uky.edu/ccts_facpub/58