A fish oil diet produces different degrees of suppression of apoB and triglyceride secretion in human apoB transgenic mouse strains.
Human apolipoprotein B (apoB) transgenic (HuBTg) mouse strains were used to assess genetic effects on the response to fish oil (FO), a source of n-3 fatty acids. A congenic HuBTg strain of the C57BL/6 (B6) background and six F1 HuBTg strains were fed a FO for 2 weeks. Different responses of plasma lipid levels to FO were observed among these strains. In particular, plasma apoB levels changed minimally in FO-fed male B6 HuBTg mice, but increased markedly ( approximately 40%) in FO-fed male FVB/NJ (FVB) x B6 F1 HuBTg mice. These strain differences were determined mainly by hepatic apoB secretion rates and were likely regulated by posttranscriptional mechanisms. In addition, plasma triglyceride (TG) levels were reduced (14%) in FO-fed B6 mice, but not in FVB x B6 mice. These strain differences were determined mainly by TG secretion rates, but were not due to differences in hepatic lipogenesis. Hepatic mRNA levels of acyl-CoA oxidase, reflective of peroxisomal beta-oxidation rate, were increased in FO-fed B6 but not in FVB x B6 mice, which could account for the difference in TG secretion rates. In summary, differential effects of FO on plasma apoB and TG levels in B6 and FVB x B6 HuBTg mice were associated with strain differences in hepatic apoB and TG secretion and in peroxisomal beta-oxidation.
Ko
Carol
C
Department of Medicine, Columbia University, College of Physicians & Surgeons, New York, NY 10032, USA.
O'Rourke
Shawn M
SM
Huang
Li-Shin
LS
D042962:Acyl-CoA Oxidase / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001055:Apolipoproteins B / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D005395:Fish Oils / Q000008:administration & dosage*; D005786:Gene Expression Regulation; D006801:Humans; D008099:Liver / Q000378:metabolism; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D010084:Oxidation-Reduction; D020675:Peroxisomes / Q000201:enzymology / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D011973:Receptors, LDL / Q000378:metabolism; D013045:Species Specificity; D014280:Triglycerides / Q000097:blood / Q000235:genetics / Q000378:metabolism*
D001055:Apolipoproteins B; D005395:Fish Oils; D012333:RNA, Messenger; D011973:Receptors, LDL; D014280:Triglycerides; D042962:Acyl-CoA Oxidase