The apolipoprotein A5 gene -1131T-->C polymorphism affects vitamin E plasma concentrations in type 2 diabetic patients.
BACKGROUND
Variations of the apolipoprotein A5 (APOA5) gene are strongly associated with hypertriglyceridemia. Vitamin E is transported in triglyceride (TG)-rich lipoproteins and therefore could also be modulated by apoAV. Patients with type 2 diabetes have a tendency towards high TG values and increased oxidative stress.


METHODS
We examined the impact of genetic APOA5 variation (-1131T-->C) on vitamin E and oxidative status in 169 non-smoker type 2 diabetic patients. Plasma samples were analyzed for lipids, lipoproteins, vitamin E, oxidized low-density lipoprotein (oxLDL), lipoperoxides, autoantibodies against oxLDL and diene formation of LDL.


RESULTS
Vitamin E concentrations were higher in TC carriers compared with TT carriers (45.48+/-8.20 micromol/L vs. 40.32+/-10.47 micromol/L; p=0.02). The prevalence of the TC genotype was 2.6-fold higher among individuals with high vitamin E concentrations (p=0.02). The APOA5 polymorphism did not determine any differences in oxidative status. Fasting TG concentration was a significant 21% higher in carriers of the TC genotype (p=0.04) due to higher TG concentrations in very-low-density lipoprotein (VLDL) and high-density lipoprotein.


CONCLUSIONS
The APOA5-1131T-->C polymorphism is associated with both higher vitamin E concentrations and higher VLDL-TGs in diabetic patients.
Girona
Josefa
J
Unitat de Recerca en Lípids i Arteriosclerosi, IRCIS, Hospital Universitari Sant Joan, Universitat Rovira i Virgili, Reus, Spain.
Guardiola
Montse
M
Cabré
Anna
A
Manzanares
Josep M
JM
Heras
Mercedes
M
Ribalta
Josep
J
Masana
Lluís
L
D000328:Adult; D000368:Aged; D000072040:Apolipoprotein A-V; D001054:Apolipoproteins A / Q000235:genetics*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000235:genetics*; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D008055:Lipids / Q000737:chemistry; D008077:Lipoproteins, LDL / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress; D011110:Polymorphism, Genetic; D014280:Triglycerides / Q000378:metabolism; D014810:Vitamin E / Q000097:blood* / Q000378:metabolism
C437704:APOA5 protein, human; D000072040:Apolipoprotein A-V; D001054:Apolipoproteins A; D008055:Lipids; D008077:Lipoproteins, LDL; D014280:Triglycerides; D014810:Vitamin E