Department of Life Science and Chemistry, Graduate School of Natural Science and Technology, Gifu University, 1-1 Yanagido, Gifu-shi, Gifu 501-1193, Japan.
Department of Life Science and Chemistry, Graduate School of Natural Science and Technology, Gifu University, 1-1 Yanagido, Gifu-shi, Gifu 501-1193, Japan; Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu-shi, Gifu 501-1193, Japan.
Nutr Res. 2021 Apr;88:28-33. doi: 10.1016/j.nutres.2020.12.022. Epub 2020 Dec 25.
ELOVL fatty acid elongase 6 (ELOVL6) is a long-chain fatty acid elongase, and the hepatic expression of the Elovl6 gene and accumulation of triglycerides (TG) are enhanced by long-term high-fructose intake. Fatty acid synthesis genes, including Elovl6, are regulated by lipogenic transcription factors, sterol regulatory element-binding protein 1c (SREBP-1c) and carbohydrate-responsive element-binding protein (ChREBP). In addition, carbohydrate signals induce the expression of fatty acid synthase not only via these transcription factors but also via histone acetylation. Since a major lipotrope, myo-inositol (MI), can repress short-term high-fructose-induced fatty liver and the expression of fatty acid synthesis genes, we hypothesized that MI might influence SREBP-1c, ChREBP, and histone acetylation of Elovl6 in fatty liver induced by even short-term high-fructose intake. This study aimed to investigate whether dietary supplementation with MI affects Elovl6 expression, SREBP-1 and ChREBP binding, and acetylation of histones H3 and H4 at the Elovl6 promoter in short-term high-fructose diet-induced fatty liver in rats. Rats were fed a control diet, high-fructose diet, or high-fructose diet supplemented with 0.5% MI for 10 days. This study showed that MI supplementation reduced short-term high-fructose diet-induced hepatic expression of the Elovl6 gene, ChREBP binding, but not SREBP-1 binding, and acetylation of histones H3 and H4 at the Elovl6 promoter.
ELOVL 脂肪酸延长酶 6(ELOVL6)是一种长链脂肪酸延长酶,长期高果糖摄入会增强 Elovl6 基因的肝表达和甘油三酯(TG)的积累。脂肪酸合成基因,包括 Elovl6,受脂肪生成转录因子固醇调节元件结合蛋白 1c(SREBP-1c)和碳水化合物反应元件结合蛋白(ChREBP)调节。此外,碳水化合物信号不仅通过这些转录因子,还通过组蛋白乙酰化诱导脂肪酸合酶的表达。由于主要的脂源肌醇(MI)可以抑制短期高果糖诱导的脂肪肝和脂肪酸合成基因的表达,我们假设 MI 可能会影响 SREBP-1c、ChREBP 和 Elovl6 启动子处的组蛋白 H3 和 H4 的乙酰化,即使是在短期高果糖摄入引起的脂肪肝中也是如此。本研究旨在探讨膳食补充 MI 是否会影响短期高果糖饮食诱导的大鼠脂肪肝中 Elovl6 表达、SREBP-1 和 ChREBP 结合以及 Elovl6 启动子处组蛋白 H3 和 H4 的乙酰化。大鼠分别喂食对照饮食、高果糖饮食或高果糖饮食补充 0.5%MI 10 天。本研究表明,MI 补充可降低短期高果糖饮食诱导的肝脏 Elovl6 基因表达、ChREBP 结合,但不降低 SREBP-1 结合以及 Elovl6 启动子处组蛋白 H3 和 H4 的乙酰化。