Dietary Flavonoids Increase Plasma Very Long-Chain (n-3) Fatty Acids in Rats1,2 1. Marie-Claire Toufektsian3, 2. Patricia Salen3, 3. François Laporte4, 4. Chiara Tonelli5, and 5. Michel de Lorgeril3,*
Abstract
Flavonoids probably contribute to the health benefits associated with the consumption of fruit and vegetables. However, the mechanisms by which they exert their effects are not fully elucidated. PUFA of the (n-3) series also have health benefits. Epidemiological and clinical studies have suggested that wine flavonoids may interact with the metabolism of (n-3) PUFA and increase their blood and cell levels. The present studies in rats were designed to assess whether flavonoids actually increase plasma levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), the main very long-chain (n-3) PUFA. Rats were fed a corn-derived anthocyanin (ACN)-rich (ACN-rich) or ACN-free diet with constant intakes of plant and marine (n-3) PUFA for 8 wk (Expt. 1). Plasma fatty acids were measured by GC. The ACN-rich diet contained ~0.24 ± 0.01 mg of ACN/g pellets. There were no significant differences between groups in the main saturated, monounsaturated, and (n-6) fatty acids. In contrast, plasma EPA and DHA were greater in the ACN-rich diet group than in the ACN-free diet group (P < 0.05). We obtained similar results in 2 subsequent experiments in which rats were administered palm oil (80 μL/d) and consumed the ACN-rich or ACN-free diet (Expt. 2) or were supplemented with fish oil (60 mg/d, providing 35 mg DHA and 12 mg EPA) and consumed the ACN-rich or ACN-free diet (Expt. 3). In both experiments, plasma EPA and DHA were significantly greater in the ACN-rich diet group. These studies demonstrate that the consumption of flavonoids increases plasma very long-chain (n-3) PUFA levels. These data confirm previous clinical and epidemiological studies and provide new insights into the health benefits of flavonoids.
90 szczurów podzielono na 3 grupy, które były karmione przez 8 tygodni dietą zgodną z poniższym opisem:
Three experiments were conducted successively using 3 different groups of rats. Expt. 1: To test the effects of ACN in rats fed a standard diet, the rats were randomized into 2 experimental groups (n = 15/group) for an 8-wk feeding trial during which they received either the ACN-free or the ACN-rich diet. Expt. 2: To test the effects of ACN in rats fed a saturated fat-rich diet, they were fed either the ACN-free or the ACN-rich diet in combination with a daily oral administration of palm oil (80 μL/d, Marka) in both groups for 8 wk (n = 15/group). In addition to the standard diet, palm oil provided 37 mg/d of SFA, 28 mg/d of monounsaturated fatty acids, and 7 mg/d of PUFA. The palm oil contained no EPA or DHA. Expt. 3: To test the effects of ACN in rats fed an (n-3) PUFA-rich diet, they were fed either the ACN-free or the ACN-rich diet in combination with daily oral administration of fish oil (60 mg/d; IsodisNatura) in both groups supplying ~35 mg/d DHA and 12 mg/d EPA for 8 wk (n = 15/group).
Wykazano iż szczury, karmione dietą bogatą w antocyjany miały wyższe stężenie kwasów omega3 we krwi w porównaniu z grupą szczurów karmionych dietą nie zawierającą antocyjanów. Poziom kwasów tłuszczowych nasyconych oraz jednonienasyconych, kwasów tłuszczowych omega-6, cholesterolu, triglicerydów, kwasu oleinowego nie różnił się znacząco u poszczególnych grup szczurów. Co obrazuje poniższa tabela.
Procentowy wzrost EPA we krwi w grupach wg. kolejności wyniósł 41, 25 i 24%. Wzrost DHA był niższy, i wyniósł on wg. kolejności 16, 10 i 16%. Wyższy wzrost kwasu EPA we krwi wynika z łatwiejszej jego syntezy w organizmie.
Sugestią jest, iż antocyjany mogą powodować wzrost n-3 we krwi poprzez konwersję kwasu alfa-linolenowego do dłuższych kwasów EPA i DHA oraz wspomagać absorpcję powyższych kwasów do jelit, co może być przyczyną wzrostu ich stężenia we krwi. U szczurów otrzymujących większe ilości EPA/DHA nie zaobserwowano mimo wszystko wyższego wzrostu o3 we krwi.
1. Interactions of wine drinking with omega-3 fatty acids in patients with coronary heart disease: a fish-like effect of moderate wine drinking. Am Heart J. 2008;155:175-81.
2.Alcohol drinking and n-3 polyunsaturated fatty acids in healthy men and women from 3 European populations. Am J Clin Nutr. 2009;89:354-62.
Zmieniony przez - Skalar. w dniu 2011-04-07 20:00:44