Ingested cocoa can prevent high-fat diet-induced obesity by regulating the expression of genes for fatty acid metabolism.
OBJECTIVE
We previously found that ingested cocoa decreased visceral adipose tissue weight in rat. To elucidate the molecular mechanisms of that effect, we carried out experiments aimed at analyzing biochemical parameters and gene expression profiles.


METHODS
Rats were fed either of two high-fat diets, differing only in supplementation with real or mimetic cocoa. On day 21, body weights, mesenteric white adipose tissue weights, and concentrations of serum triacylglycerol were measured. To investigate the molecular mechanisms underlying the effects of cocoa on lipid metabolism and triacylglycerol accumulation, we examined gene expression profiles in liver and mesenteric white adipose tissues using the GeneChip microarray system.


RESULTS
Final body weights and mesenteric white adipose tissue weights were significantly lower in rats fed the real cocoa diet than in those fed the mimetic cocoa diet (P<0.05), and serum triacylglycerol concentrations tended to be lower in rats fed the real cocoa diet (P=0.072). DNA microarray analysis showed that cocoa ingestion suppressed the expression of genes for enzymes involved in fatty acid synthesis in liver and white adipose tissues. In white adipose tissue, cocoa ingestion also decreased the expression of genes for fatty acid transport-relating molecules, whereas it upregulated the expression of genes for uncoupling protein-2 as a thermogenesis factor.


CONCLUSIONS
Ingested cocoa can prevent high-fat diet-induced obesity by modulating lipid metabolism, especially by decreasing fatty acid synthesis and transport systems, and enhancement of part of the thermogenesis mechanism in liver and white adipose tissue.
Matsui
Naoko
N
Research Institute, Morinaga & Co., Ltd., Kanagawa, Japan. n-matsui-jj@morinaga.co.jp
Ito
Ryoichi
R
Nishimura
Eisaku
E
Yoshikawa
Mariko
M
Kato
Masatoshi
M
Kamei
Masanori
M
Shibata
Haruki
H
Matsumoto
Ichiro
I
Abe
Keiko
K
Hashizume
Shuichi
S
D000273:Adipose Tissue / Q000378:metabolism*; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002099:Cacao / Q000378:metabolism; D004041:Dietary Fats / Q000008:administration & dosage / Q000009:adverse effects / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism*; D020869:Gene Expression Profiling; D015971:Gene Expression Regulation, Enzymologic; D008099:Liver / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D009765:Obesity / Q000209:etiology / Q000378:metabolism / Q000517:prevention & control*; D020411:Oligonucleotide Array Sequence Analysis; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D014280:Triglycerides / Q000097:blood
D004041:Dietary Fats; D005227:Fatty Acids; D014280:Triglycerides