Centre des Sciences du Goût et de l'Alimentation, AgroSup Dijon, CNRS, INRAE, Université Bourgogne Franche-Comté, F-21000, Dijon, France.
Centre des Sciences du Goût et de l'Alimentation, AgroSup Dijon, CNRS, INRAE, Université Bourgogne Franche-Comté, F-21000, Dijon, France; Laboratoire de Biochimie Médicale, Plateforme de Biologie Hospitalo-Universitaire, F-21000, Dijon, France.
Exp Eye Res. 2020 Jul;196:108059. doi: 10.1016/j.exer.2020.108059. Epub 2020 May 5.
Structure and function of the retina mainly rely on its fatty acid (FA) composition. Evidence from epidemiological studies and from animal experiments indicates that FA composition of the retina is influenced by the diet. Mice under chronic high-fat diet (HFD) develop metabolic syndrome, a risk factor for diabetes that is associated with structural and functional alterations of the retina. Here, we studied the impact of chronic exposure of mice to HFD on retinal FA composition. C57BL/6 J male mice were fed either a chow diet or a HFD for 11 weeks. As expected, HFD induced weight gain, adiposity, hyperglycemia and dyslipidemia. The retinal FA composition was determined by gas chromatography coupled to flame ionization detection. No significant change in the relative abundance of total saturated FAs (SFAs), total monounsaturated FAs (MUFAs) or total polyunsaturated FAs (PUFAs) was observed. However, retinas of HFD-fed mice displayed decreased amounts of C24:0 (p = 0.0231), C16:1n-7 (p < 0.0001), C18:1n-7 (p < 0.0001), C20:3n-9 (p = 0.0425) and C20:3n-6 (p = 0.0008), and an increased amount of C20:2n-6 (p < 0.0001). In addition, the ratio of linoleic acid (C18:2n-6) to alpha-linolenic acid (C18:3n-3) was increased in the retinas of HFD-fed mice (15.0 ± 0.8 versus 11.8 ± 0.6 in HFD and CD, respectively, p = 0.0045). No modification in the contents of arachidonic acid (C20:4n-6, AA) and docosahexaenoic acid (C22:6n-3, DHA) were observed. Analysis of dimethylacetals (DMA), which are residues of plasmalogens (Pls), revealed that the amount of Pls containing octadecanal-aldehydes (DMA C18:0) was significantly increased in HFD-fed mice (p = 0.0447). This increase was, at least in part, balanced by a decrease in Pls containing 7-octadecanal-aldehydes (DMA C18:1n-7) (p = 0.0007). In conclusion, HFD had an impact on the relative proportion of essential dietary fatty acids linoleic acid and alpha-linolenic acid that are incorporated in the retina. However, this imbalance in PUFA precursors did not alter the content of the two major retinal long-chain PUFAs, AA and DHA. HFD consumption also led to alterations in the retinal SFAs, MUFAs and Pls profiles.
视网膜的结构和功能主要依赖于其脂肪酸 (FA) 组成。来自流行病学研究和动物实验的证据表明，视网膜的 FA 组成受饮食的影响。长期高脂肪饮食 (HFD) 的小鼠会出现代谢综合征，这是糖尿病的一个风险因素，与视网膜的结构和功能改变有关。在这里，我们研究了慢性暴露于 HFD 对小鼠视网膜 FA 组成的影响。将 C57BL/6J 雄性小鼠分别喂食标准饮食或 HFD 11 周。正如预期的那样，HFD 导致体重增加、肥胖、高血糖和血脂异常。通过气相色谱法结合火焰离子化检测来确定视网膜 FA 组成。未观察到总饱和脂肪酸 (SFAs)、总单不饱和脂肪酸 (MUFAs) 或总多不饱和脂肪酸 (PUFAs) 的相对丰度有显著变化。然而，HFD 喂养的小鼠的视网膜显示出 C24:0 含量减少（p=0.0231）、C16:1n-7 含量减少（p<0.0001）、C18:1n-7 含量减少（p<0.0001）、C20:3n-9 含量减少（p=0.0425）和 C20:3n-6 含量减少（p=0.0008），C20:2n-6 含量增加（p<0.0001）。此外，HFD 喂养小鼠视网膜中亚油酸（C18:2n-6）与α-亚麻酸（C18:3n-3）的比例增加（HFD 和 CD 分别为 15.0±0.8 和 11.8±0.6，p=0.0045）。未观察到花生四烯酸（C20:4n-6，AA）和二十二碳六烯酸（C22:6n-3，DHA）含量的改变。二甲乙缩醛 (DMA) 的分析，它们是溶血磷脂 (Pls) 的残留物，表明 HFD 喂养的小鼠中含有十八醛的 Pls 数量显著增加（p=0.0447）。这种增加至少部分被含有 7-十八醛的 Pls 减少所平衡（p=0.0007）。总之，HFD 对必需膳食脂肪酸亚油酸和α-亚麻酸在视网膜中的相对比例有影响。然而，这种多不饱和脂肪酸前体的不平衡并没有改变两种主要的视网膜长链多不饱和脂肪酸，AA 和 DHA 的含量。HFD 的摄入也导致视网膜 SFAs、MUFAs 和 Pls 谱的改变。
