Reduced fecal sterol excretion in subjects with familial hypoalphalipoproteinemia.
BACKGROUND
Fecal bile acid and neutral sterol excretion are the obligate endpoints of the reverse cholesterol transport pathway (RCT). In studies in mice, no evidence was found for a relation between HDL-cholesterol (HDL-c) levels and fecal sterol excretion. In this study, we have evaluated this relationship in patients with isolated low HDL-c versus controls.


RESULTS
Fecal sterol excretion was studied in 12 subjects with familial hypoalphalipoproteinemia (FHA) and 11 healthy controls. Compared to the controls (8.9+/-6.3mg/kg/day), neutral sterol excretion was significantly lower in the FHA group (4.0+/-2.4mg/kg/day). Fecal bile acid excretion showed a similar pattern. Across the groups, a strong positive correlation between HDL-c and fecal neutral sterol excretion was found (r=0.53; p=0.01).


CONCLUSIONS
Isolated low HDL-c levels in humans are associated with reduced fecal sterol excretion suggesting that in humans HDL regulates the final step in the RCT pathway at low HDL-c levels.
Harchaoui
Karim El
KE
Department of Vascular Medicine, Academic Medical Centre, Amsterdam, The Netherlands.
Franssen
Remco
R
Hovingh
G Kees
GK
Bisoendial
Radjesh J
RJ
Stellaard
Frans
F
Kuipers
Folkert
F
Kastelein
John J P
JJ
Kuivenhoven
Jan Albert
JA
Stroes
Erik S G
ES
Groen
Albert K
AK
D000328:Adult; D001647:Bile Acids and Salts / Q000378:metabolism; D016022:Case-Control Studies; D008076:Cholesterol, HDL / Q000097:blood*; D015536:Down-Regulation; D005243:Feces / Q000737:chemistry*; D005260:Female; D006801:Humans; D052456:Hypoalphalipoproteinemias / Q000097:blood / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D013261:Sterols / Q000378:metabolism*; D013997:Time Factors
D001647:Bile Acids and Salts; D008076:Cholesterol, HDL; D013261:Sterols