The Pro12Ala polymorphism of the PPAR-gamma2 gene affects associations of fish intake and marine n-3 fatty acids with glucose metabolism.
OBJECTIVE
Data on associations between marine n-3 fatty acids and glucose metabolism are inconsistent. Therefore, we explored effects of the Pro12Ala polymorphism in peroxisome proliferator-activated receptor (PPAR)-gamma2 gene on associations of fish intake and dietary and plasma eicosapentaenoic and docosahexaenoic acid with glucose metabolism. The design comprises of the cross-sectional analysis.


METHODS
The Pro12Ala variant in the PPAR-gamma2 (PPARG) gene was genotyped in 571 non-diabetic relatives of subjects with type II diabetes. The dietary intake was measured by a 3-day food record, and the plasma cholesterol ester fatty acid composition was analysed with gas chromatography. Associations of dietary and plasma variables with insulin resistance and fasting and 2-h glucose and free fatty acid concentrations were analysed with multiple linear regression analysis.


RESULTS
In men, there was a significant interaction between PPARG polymorphism and plasma docosahexaenoic acid on fasting free fatty acid concentration (P=0.036), and genotype-stratified models showed an inverse association in Pro homozygotes only (P=0.028). In women, the proportion of plasma eicosapentaenoic acid was higher in Ala-allele carriers compared to Pro homozygotes (1.67 vs 1.44% respectively, P=0.006). A significant interaction between PPARG polymorphism and fish intake on 2-h glucose was found in women (P=0.021), and genotype-stratified models suggested an inverse association in Ala-allele carriers only (P=0.039).


CONCLUSIONS
The findings suggest that PPARG polymorphism might affect the plasma proportion of eicosapentaenoic acid and modulate the associations of fish intake and marine n-3 fatty acids with glucose metabolism and fasting free fatty acids.
Ylönen
S K
SK
Department of Applied Chemistry and Microbiology, Division of Nutrition, University of Helsinki, Helsinki, Finland. katriina.ylonen@helsinki.fi
Salminen
I
I
Lyssenko
V
V
Virtanen
S M
SM
Groop
L
L
Aro
A
A
Saloranta
C
C
D000409:Alanine; D000483:Alleles; D001786:Blood Glucose / Q000378:metabolism*; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000235:genetics; D015930:Diet Records; D004281:Docosahexaenoic Acids / Q000008:administration & dosage / Q000097:blood; D015118:Eicosapentaenoic Acid / Q000008:administration & dosage / Q000097:blood; D005230:Fatty Acids, Nonesterified / Q000097:blood*; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage* / Q000097:blood; D005260:Female; D005838:Genotype; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000235:genetics; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D047495:PPAR gamma / Q000235:genetics*; D011110:Polymorphism, Genetic; D011392:Proline; D012737:Sex Factors
D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D015525:Fatty Acids, Omega-3; D007328:Insulin; D008055:Lipids; D047495:PPAR gamma; D004281:Docosahexaenoic Acids; D011392:Proline; D015118:Eicosapentaenoic Acid; D000409:Alanine