Familial hypobetalipoproteinemia due to apolipoprotein B R463W mutation causes intestinal fat accumulation and low postprandial lipemia.
OBJECTIVE
Familial hypobetalipoproteinemia (FHBL) is characterized by inherited low plasma levels of apolipoprotein B (apoB)-containing lipoproteins. In this paper we investigated whether the already described APOB R463W missense mutation, a FHBL mutation able to impair the activity of microsomal triglyceride transfer protein (MTP), may cause intestinal fat accumulation and reduced postprandial lipemia.


METHODS
Four out of five probands harboring APOB R463W mutation were compared with six healthy controls and six patients with celiac disease (CD). An oral fat load supplemented with retinyl palmitate (RP) was administered and a gastro-duodenal endoscopy with biopsy was performed.


RESULTS
Plasma triglyceride area under curves was significantly reduced in FHBL probands compared to controls and CD patients; the proportion of absorbed RP was similar to that of CD patients. Only the intestinal biopsies of FHBL patients showed lipids accumulating within the duodenal mucosa.


CONCLUSIONS
FHBL due to R463W apoB mutation is a cause of intestinal fat accumulation and postprandial lipid absorption impairment.
Department of Clinical Medicine and Emerging Diseases, University of Palermo, Italy.
Davide
D
Noto
Angelo B
AB
Cefalù
Alessandra
A
Cannizzaro
Mariangela
M
Minà
Francesca
F
Fayer
Vincenza
V
Valenti
Carlo M
CM
Barbagallo
Antonino
A
Tuttolomondo
Antonio
A
Pinto
Carmelo
C
Sciumè
Giuseppe
G
Licata
Maurizio
M
Averna
D000293:Adolescent; D000328:Adult; D001055:Apolipoproteins B / Q000235:genetics*; D002352:Carrier Proteins; D002648:Child; D004224:Diterpenes; D005260:Female; D006801:Humans; D006949:Hyperlipidemias / Q000235:genetics*; D052476:Hypobetalipoproteinemia, Familial, Apolipoprotein B / Q000235:genetics* / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D050152:Intra-Abdominal Fat / Q000378:metabolism*; D050356:Lipid Metabolism; D008297:Male; D008875:Middle Aged; D020125:Mutation, Missense; D019518:Postprandial Period; D000084562:Retinyl Esters; D014280:Triglycerides / Q000097:blood; D014801:Vitamin A / Q000031:analogs & derivatives / Q000378:metabolism
D001055:Apolipoproteins B; D002352:Carrier Proteins; D004224:Diterpenes; D000084562:Retinyl Esters; D014280:Triglycerides; C106092:microsomal triglyceride transfer protein; D014801:Vitamin A; C014794:retinol palmitate