Estrogen markedly increases LDL-receptor activity in hypercholesterolemic patients.
We investigated the change in low-density lipoprotein receptor activity following the administration of estrogen to patients with hypercholesterolemia (HC). Studies were conducted in 16 patients with HC (total cholesterol (TC)>220 mg/dL) and 133 healthy control subjects. LDL-R activity was measured by fluorocytometry. Three of sixteen patients with HC showed low LDL-R activity below 80% together with extremely high serum levels of TC and LDL cholesterol (LDL-C). LDL-R activity showed an inverse correlation with serum levels of TC and LDL-C (p<0.05, respectively). Two women with initially low LDL-R activity who showed a marked increase in LDL-R activity exhibited a normalized activity at four and eight weeks after estriol administration, proportional to the reduction in serum levels of TC and LDL-C. One man with an initially extremely low LDL-R activity showed no abnormality at the sites of exons 7, 14, 17 and intron 12 by the PCR-DGGE method, which are common sites for point-mutations of LDL-R among Japanese patients with HC. Estrogen reduced serum levels of TC and LDL-C in patients with HC, at least in part, via an increase in the LDL-R activity of patients with HC and an initially low LDL-R activity.
Inukai
T
T
Department of Medicine, Koshigaya Hospital, Dokkyo University School of Medicine, Minami-Koshigaya, Japan. t-inukai@dokkyomed.ac.jp
Takanashi
K
K
Takebayashi
K
K
Tayama
K
K
Aso
Y
Y
Takiguchi
Y
Y
Takemura
Y
Y
D000328:Adult; D002784:Cholesterol / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D004964:Estriol / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D006938:Hyperlipoproteinemia Type II / Q000097:blood / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism*; D007150:Immunohistochemistry / Q000379:methods; D007564:Japan; D008214:Lymphocytes / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D011973:Receptors, LDL / Q000378:metabolism*; D013223:Statistics as Topic
D008078:Cholesterol, LDL; D011973:Receptors, LDL; D002784:Cholesterol; D004964:Estriol