Zinc deficiency decreases plasma level and hepatic mRNA abundance of apolipoprotein A-I in rats and hamsters.
The influence of Zn deficiency on the plasma level as well as the hepatic and intestinal gene expression of apolipoprotein (apo) A-I was examined in rats and hamsters. Male Sprague-Dawley rats (8 wk old) and Golden Syrian hamsters (7 wk old) were assigned to three dietary treatments: Zn adequate (ZA, 30 mg Zn/kg diet), Zn deficient (ZD, <0.5 mg Zn/kg diet), and Zn replete (ZDA, ZD animals fed the ZA diet for the last 2 days). The dietary treatments lasted for 18 days for rats or 6 wk for hamsters. For the measurement of apoA-I mRNA abundance, hamster apoA-I cDNA was cloned from the small intestine. The full-length 905-base pair cDNA shared approximately 80% similarity with the human, rat, and mouse apoA-I cDNAs. Hepatic and plasma Zn levels were reduced in ZD animals but normalized in ZDA rats and increased in ZDA hamsters compared with ZA animals. Zn deficiency reduced plasma apoA-I and hepatic apoA-I mRNA levels 13 and 38%, respectively, in ZD rats. The 2 days of Zn replenishment raised plasma apoA-I and hepatic apoA-I mRNA levels in ZDA rats by 34 and 28%, respectively, higher than ZA rats. Similarly, these levels were decreased by 18 and 25%, respectively, in ZD hamsters but normalized in ZDA hamsters compared with ZA hamsters. In contrast to the alterations of hepatic apoA-I mRNA levels, neither Zn deficiency nor subsequent Zn repletion produced alterations in the intestinal apoA-I mRNA abundance. Data from this study demonstrated that Zn deficiency specifically decreases hepatic apoA-I gene expression, which may at least be partly responsible for the reduction of plasma apoA-I levels.
Wu
J Y
JY
Department of Nutritional Sciences, University of Arizona, Tucson, Arizona 85721, USA.
Reaves
S K
SK
Wang
Y R
YR
Wu
Y
Y
Lei
P P
PP
Lei
K Y
KY
D000595:Amino Acid Sequence / Q000235:genetics; D000818:Animals; D016632:Apolipoprotein A-I / Q000097:blood* / Q000235:genetics*; D001483:Base Sequence / Q000235:genetics; D006224:Cricetinae; D018076:DNA, Complementary / Q000235:genetics; D004032:Diet; D006801:Humans; D008099:Liver / Q000378:metabolism*; D008297:Male; D008647:Mesocricetus; D051379:Mice; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012016:Reference Values; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015032:Zinc / Q000008:administration & dosage / Q000172:deficiency*
D016632:Apolipoprotein A-I; D018076:DNA, Complementary; D012333:RNA, Messenger; D015032:Zinc