TY - JOUR
T1 - Antagonistic effects of vitamin D and parathyroid hormone on lipoprotein lipase in cultured adipocytes
AU - Querfeld, Uwe
AU - Hoffmann, Michael M.
AU - Klaus, GÜNTER
AU - Eifinger, Frank
AU - Ackerschott, Marion
AU - Michalk, Dietrich
AU - Kern, Philip A.
PY - 1999/10
Y1 - 1999/10
N2 - The effects of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) (calcitriol) and parathyroid hormone (PTH) on synthesis and secretion of lipoprotein lipase (LPL) were studied in 3T3-L1 adipocytes. Expression of the vitamin D receptor was demonstrated by saturation kinetics with radiolabeled calcitriol. Incubation with calcitriol (10-8 M) for up to 4 d resulted in a time- dependent significant increase in heparin-releasable LPL activity (LPLa) accompanied by a significant increase in LPL mRNA. In contrast, incubation with intact (1-84) PTH (10-6 to 10-9 M) produced a time- and dose- dependent significant decrease in LPLa, but no change in LPL mRNA. The effect of PTH (24-h incubation, 10-8 M) could be prevented by the calcium channel blocker verapamil. Coincubation with both calcitriol and PTH at equimolar concentration (10-8 M) resulted in an increase in LPLa and LPL mRNA. These data indicate an antagonistic role for calcitriol and PTH in the regulation of LPL, possibly mediated by intracellular calcium, which may contribute to the alterations in lipoprotein metabolism occurring in uremia.
AB - The effects of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) (calcitriol) and parathyroid hormone (PTH) on synthesis and secretion of lipoprotein lipase (LPL) were studied in 3T3-L1 adipocytes. Expression of the vitamin D receptor was demonstrated by saturation kinetics with radiolabeled calcitriol. Incubation with calcitriol (10-8 M) for up to 4 d resulted in a time- dependent significant increase in heparin-releasable LPL activity (LPLa) accompanied by a significant increase in LPL mRNA. In contrast, incubation with intact (1-84) PTH (10-6 to 10-9 M) produced a time- and dose- dependent significant decrease in LPLa, but no change in LPL mRNA. The effect of PTH (24-h incubation, 10-8 M) could be prevented by the calcium channel blocker verapamil. Coincubation with both calcitriol and PTH at equimolar concentration (10-8 M) resulted in an increase in LPLa and LPL mRNA. These data indicate an antagonistic role for calcitriol and PTH in the regulation of LPL, possibly mediated by intracellular calcium, which may contribute to the alterations in lipoprotein metabolism occurring in uremia.
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M3 - Article
C2 - 10505692
AN - SCOPUS:0032850535
SN - 1046-6673
VL - 10
SP - 2158
EP - 2164
JO - Journal of the American Society of Nephrology
JF - Journal of the American Society of Nephrology
IS - 10
ER -