α-亚麻酸对高脂模型大鼠组织脂肪酸代谢的影响

Effect of α-Linolenic Acid on Fatty Acid Metabolism of Rats Fed with High Fat Diet

研究不同ALA含量油脂对高脂模型大鼠组织脂肪酸代谢的影响。60只雄性Wistar大鼠分为正常组、高脂组、花生油组、13%、27%和55%ALA含量油脂组,除正常组和高脂组外,其余各组在饲喂高脂饲料的同时采用灌胃方式连续给予2 mL/kg.bw剂量的受试油。试验6周后分别测定大鼠各组织脂肪酸组成。结果表明,高脂饮食能够降低大鼠各组织n-3脂肪酸含量,但摄入不同ALA油脂可显著增加组织n-3脂肪酸含量,并具有一定的剂量效应关系;但ALA及其代谢产物EPA、DPA和DHA的累积具有组织特异性,其中肾和心组织中ALA累积高于血浆、脑及肝组织,肝和脑组织中EPA和DPA含量增加较显著,而肾和心组织中EPA含量不变,各组织DHA含量增加不显著。不同ALA油脂组C18∶3(n-6)和C20∶3(n-6)差异不显著,但与花生油组相比,其血浆、脑和肾组织C20∶4含量显著降低。因此,富含ALA含量的油脂能够增加组织中ALA及其代谢产物在组织中的含量,提高其在脑组织中的分布比例,这可能是ALA具有心血管保护作用和促进脑生长发育的作用机制之一。

In order to investigate the effect of different ALA levels of oils on fatty acid metabolism of rats fed with high fat diet,rats were divided into control（Cont） group,high fat diet（HFD） group,peanut oil（PO） group,13%,27% and 55% α-linolenic acid blend oil（ALA-BO） groups.Besides Cont and HFD groups,other rats were fed with high-fat diet and treated simultaneously with corresponding oils（2 mL/kg.bw） orally for 6 weeks.The total fatty acid composition in plasma,liver,brain,kidney and heart were determined.The results showed that high fat diet could reduce the n-3 PUFA levels in all tissues,but increasing ALA intake could result in an incorporation of n-3 PUFA in tissues and also showed a dose-effect relationship.There were some tissue-dependent differences in the increase of n-3 PUFA levels,the increase of ALA in kidney and heart was greater than that in plasma,brain and liver,and the EPA level in brain and liver enhanced significantly,but no change was observed in DPA level in kidney and heart,and there was no significant change in DHA level in tissues.No difference was revealed in C18∶ 3（n-6） and C20∶ 3（n-6） levels among 13%,27% and 55% ALA-BO groups,but C20∶ 4 level decreased significantly in plasma,brain and kidney when compared with PO group.Our data suggestted that oils rich in ALA could increase the levels of ALA and its metabolites in rat tissues and improve the relative proportion of EPA and DPA in brain,which may be one mechanism of ALA in reducing the risk of cardiovascular disease and promoting the growth of brain.