Hepatic lipase gene expression is upregulated by a cystine-rich diet in male but not in female rats.
Male and female rats fed a cystine-rich diet (5% L-cystine) became hypercholesterolemic after 2 months, with 2-fold higher cholesterol levels carried mainly by the HDL1 and HDL2 lipoprotein fractions. Post-heparin lipoprotein lipase activity was increased in male rats only (60%, P < 0.01), while hepatic lipase (HL) activity was increased in both males and females (48%, P < 0.001 and 27%, P < 0.01, respectively). In the liver, HL activity and mRNA levels were increased in males (30%, P < 0.01, and 70%, P < 0.001, respectively), but not in females. A higher correlation between HDL1-cholesterol and liver HL activity was found in male rats than in female rats. In the latter, although the cystine diet induced a virtually identical increase in HDL1-cholesterol, HL gene expression was not promoted. It is suggested that HL gene expression may be triggered by the uptake of HDL1-cholesterol in male rats, while oestrogens in female rats would counteract this effect.
Benhizia
F
F
Laboratoire de Physiopathologie de la Nutrition, INSERM U177, Paris, France.
Sérougne
C
C
Férézou
J
J
Lagrange
D
D
Malewiak
M I
MI
Griglio
S
S
D000818:Animals; D008076:Cholesterol, HDL / Q000378:metabolism; D003553:Cystine / Q000494:pharmacology*; D004032:Diet; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D006937:Hypercholesterolemia / Q000201:enzymology*; D008049:Lipase / Q000235:genetics / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D008297:Male; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D012737:Sex Factors; D015854:Up-Regulation
D008076:Cholesterol, HDL; D012333:RNA, Messenger; D003553:Cystine; D008049:Lipase