Effect of transforming growth factor-beta on lipoprotein lipase in rat mesenchymal heart cell cultures.
The effect of recombinant transforming growth factor-beta 2 (rTGF-beta 2) on lipoprotein lipase (LPL) synthesis was studied in mesenchymal rat heart cell cultures. Addition of rTGF-beta 2 to culture medium containing 20% serum resulted in a time-dependent decrease in LPL activity. With 10 ng/ml a 30% fall occurred after 12 h and only 20% of enzyme activity remained after 24 h with 5 or 10 ng/ml. The minimal effective dose of rTGF-beta 2 was 0.1 ng/ml and a 20% decrease occurred after exposure for 24 h. Antibodies specific to TGF-beta 2 blocked this effect. The decrease in enzymic activity was accompanied by a decrease in enzyme mass and LPL mRNA. Addition of rTGF-beta 2 was effective only during the first week in culture, when enzyme activity was increasing but not after 12 days when the cultures were overconfluent, and the enzyme activity was high.
Friedman
G
G
Lipid Research Laboratory, Hadassah University Hospital, Jerusalem, Israel.
Ben-Yehuda
A
A
Ben-Naim
M
M
Matsa
D
D
Stein
O
O
Stein
Y
Y
D000818:Animals; D015152:Blotting, Northern; D002478:Cells, Cultured; D003470:Culture Media; D007700:Kinetics; D008071:Lipoprotein Lipase / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D008648:Mesoderm / Q000201:enzymology*; D009206:Myocardium / Q000201:enzymology*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011994:Recombinant Proteins / Q000494:pharmacology; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
D003470:Culture Media; D012333:RNA, Messenger; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; D008071:Lipoprotein Lipase