Chan Chun-Wai, Chan Pei-Hsuan, Lin Bi-Fong
Department of Biochemical Science and Technology, College of Life Science, National Taiwan University, Taipei, Taiwan.
Front Nutr. 2022 Apr 25;9:852451. doi: 10.3389/fnut.2022.852451. eCollection 2022.
Imbalanced dietary habits are closely associated with poor micronutrients status and the development of obesity. Previous studies have shown that serum folate level is decreased in obese individuals. However, whether folate deficiency could result in adiposity is still unclear. The aim of this study was to investigate the effects of dietary folate on lipid accumulation and leptin production using both and studies. Male C57BL/6 mice were fed with a diet with (f1) or without (f0) folate in a high-fat (HF) diet containing high-sucrose (HFS-f1, HFS-f0) for 4.5-5 months in Experiment 1, or an HF diet (HF-f1, HF-f0) for 12 months in Experiment 2, or an HF diet containing high-fructose (HFF-f1, HFF-f0) for 12 months in Experiment 3, compared with the normal-fat (NF-f1, NF-f0) diet, respectively. The serum levels of folate and leptin, white adipose tissue (WAT), size of adipocytes, hepatic contents of triglyceride (TG), and cholesterol were measured. study, TG contents, proinflammatory cytokines, leptin, and expressions of hypoxia-inducible factor (HIF)-1α and lipogenesis-related genes of 3T3-L1 adipocytes cultured with (f) or without (f) folate were assayed. The results showed that folate deficiency together with a high-fat diet (HFS-f0, HF-f0, HFF-f0) had higher WAT mass, adipocyte size, serum leptin level, and hepatic TG compared to those of the folate-sufficient groups (HFS-f1, HF-f1, and HFF-f1). Folate deficiency with a high-fat high -sucrose or -fructose diet (HFS-f0, HFF-f0) significantly increased the body weight of the mice. Increased intracellular TG, leptin, monocyte chemotactic protein (MCP)-1 and interleukin (IL)-6 levels, and the expression of α and lipogenesis-related genes α, β, , and were also detected in folate-deficient 3T3-L1 adipocytes. Our results suggested that folate deficiency increased lipid accumulation and leptin production of adipocytes, and thus, inadequate folate status might be one of the risk factors for adiposity.
不均衡的饮食习惯与微量营养素缺乏及肥胖的发生密切相关。先前的研究表明,肥胖个体的血清叶酸水平会降低。然而,叶酸缺乏是否会导致肥胖仍不清楚。本研究的目的是通过体内和体外研究来探究膳食叶酸对脂质积累和瘦素产生的影响。在实验1中,将雄性C57BL/6小鼠在含高蔗糖的高脂(HF)饮食(HFS-f1、HFS-f0)中喂食4.5 - 5个月,饮食中添加(f1)或不添加(f0)叶酸;在实验2中,在高脂(HF)饮食(HF-f1、HF-f0)中喂食12个月;在实验3中,在含高果糖的高脂(HF)饮食(HFF-f1、HFF-f0)中喂食12个月,分别与正常脂肪(NF-f1、NF-f0)饮食组进行比较。检测血清叶酸和瘦素水平、白色脂肪组织(WAT)、脂肪细胞大小、肝脏甘油三酯(TG)含量和胆固醇含量。在体外研究中,检测用(f)或不用(f)叶酸培养的3T3-L1脂肪细胞的TG含量、促炎细胞因子、瘦素以及缺氧诱导因子(HIF)-1α和脂肪生成相关基因的表达。结果表明,与叶酸充足组(HFS-f1、HF-f1和HFF-f1)相比,叶酸缺乏与高脂饮食(HFS-f0、HF-f0、HFF-f0)共同作用会使WAT质量、脂肪细胞大小、血清瘦素水平和肝脏TG含量更高。叶酸缺乏与高脂高蔗糖或高果糖饮食(HFS-f0、HFF-f0)会显著增加小鼠体重。在叶酸缺乏的3T3-L1脂肪细胞中还检测到细胞内TG、瘦素、单核细胞趋化蛋白(MCP)-1和白细胞介素(IL)-6水平升高,以及α和脂肪生成相关基因α、β、 和 的表达增加。我们的结果表明,叶酸缺乏会增加脂肪细胞的脂质积累和瘦素产生,因此,叶酸状态不足可能是肥胖的危险因素之一。