Dietary lipids modify intestinal lipid-binding protein RNA abundance in diabetic and control rats.
BACKGROUND
Lipid-binding proteins have been identified in the enterocyte, including the cytosolic intestinal and liver fatty acid binding proteins (I-FABP and L-FABP, respectively) as well as the brush border membrane fatty acid transporter (FAT). It is unclear whether variations in the type of dietary lipids or diabetes modify the RNA abundance of these proteins. Diabetes is associated with an increased intestinal lipid uptake, and the lipid uptake is greater in rats fed a semisynthetic saturated fatty acid (SFA) as compared with a polyunsaturated fatty acid (PUFA) diet.


METHODS
Male Sprague-Dawley rats were injected with streptozotocin or control vehicle and fed chow or either SFA or PUFA for 2 weeks. Northern blotting was performed on RNA isolated from jejunal and ileal tissues.


RESULTS
In controls, feeding SFA as compared with PUFA reduced the jejunal abundance of I-FABP and L-FABP RNA. In diabetic rats, feeding SFA increased the ileal FAT RNA. Feeding PUFA reduced jejunal L-FABP and ileal FAT RNA in diabetic rats as compared with controls.


CONCLUSIONS
The enhanced lipid uptakes reported with feeding an SFA diet or with diabetes were not associated with parallel alterations in lipid-binding proteins. We speculate that these lipid-binding proteins act as a storage mechanism for lipids in enterocytes and are not directly involved in lipid uptake.
Drozdowski
L
L
Nutrition and Metabolism Research Group, Division of Gastroenterology, University of Alberta, Edmonton, Canada.
Clement
L
L
Keelan
M
M
Niot
I
I
Clandinin
M T
MT
Agellon
L
L
Wild
G
G
Besnard
P
P
Thomson
A B R
AB
D000818:Animals; D002352:Carrier Proteins / Q000187:drug effects*; D003921:Diabetes Mellitus, Experimental; D004041:Dietary Fats / Q000494:pharmacology*; D050556:Fatty Acid-Binding Proteins; D007422:Intestines / Q000187:drug effects; D008297:Male; D026901:Membrane Transport Proteins / Q000187:drug effects*; D023421:Models, Animal; D012313:RNA; D051381:Rats; D017207:Rats, Sprague-Dawley
D002352:Carrier Proteins; D004041:Dietary Fats; C493321:Fabp1 protein, rat; D050556:Fatty Acid-Binding Proteins; D026901:Membrane Transport Proteins; D012313:RNA