Effects of n-3 fatty acids on macro- and microvascular function in subjects with type 2 diabetes mellitus.
BACKGROUND
Recent evidence supports the protective effects of n-3 (omega-3) fatty acids (n-3 FAs), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), on vascular function.


OBJECTIVE
We investigated the effects of EPA and DHA on postprandial vascular function in subjects with type 2 diabetes mellitus.


METHODS
In a double-blind, placebo-controlled, randomized, crossover manner, 34 subjects with type 2 diabetes mellitus received daily either 2 g purified EPA/DHA (termed n-3 FAs) or olive oil (placebo) for 6 wk. At the end of this period, we measured macrovascular (brachial ultrasound of flow-mediated dilatation; FMD) and microvascular [laser-Doppler measurements of reactive hyperemia (RH) of the hand] function at fasting and 2, 4, and 6 h after a high-fat meal (600 kcal, 21 g protein, 41 g carbohydrates, 40 g fat).


RESULTS
Fasting vascular function remained unchanged after n-3 FAs and placebo. Postprandial FMD decreased from fasting after placebo, with a maximum decrease (38%) at 4 h-an effect that was significantly reduced (P = 0.03 for time x treatment interaction) by n-3 FA supplementation (maximum decrease in FMD was at 4 h: 13%). RH remained unchanged after placebo, whereas it improved significantly (P = 0.04 for time x treatment interaction) after n-3 FA supplementation (maximum increase was at 2 h: 27%).


CONCLUSIONS
In subjects with type 2 diabetes mellitus, 6 wk of supplementation with n-3 FAs reduced the postprandial decrease in macrovascular function relative to placebo. Moreover, n-3 FA supplementation improved postprandial microvascular function. These observations suggest a protective vascular effect of n-3 FAs.
Stirban
Alin
A
Ruhr-University Bochum, Bochum, Germany. stirban@web.de.
Nandrean
Simona
S
Götting
Christian
C
Tamler
Ronald
R
Pop
Alexandra
A
Negrean
Monica
M
Gawlowski
Thomas
T
Stratmann
Bernd
B
Tschoepe
Diethelm
D
D000328:Adult; D000368:Aged; D018592:Cross-Over Studies; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy*; D004032:Diet; D019587:Dietary Supplements; D004281:Docosahexaenoic Acids / Q000494:pharmacology* / Q000627:therapeutic use; D004311:Double-Blind Method; D015118:Eicosapentaenoic Acid / Q000494:pharmacology* / Q000627:therapeutic use; D005260:Female; D006801:Humans; D006940:Hyperemia / Q000188:drug therapy*; D055806:Microvessels / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000502:physiology; D008875:Middle Aged; D000069463:Olive Oil; D010938:Plant Oils / Q000494:pharmacology; D019518:Postprandial Period / Q000187:drug effects; D014463:Ultrasonography; D014664:Vasodilation / Q000187:drug effects*
D000069463:Olive Oil; D010938:Plant Oils; D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid