Laboratory of Molecular Iron Metabolism, College of Life Science, Hebei Normal University, Shijiazhuang, Hebei Province, China.
Hebei Key Laboratory of Metabolic Diseases, Hebei General Hospital, Shijiazhuang, Hebei, China.
J Food Biochem. 2021 Jan;45(1):e13578. doi: 10.1111/jfbc.13578. Epub 2020 Dec 2.
Nonalcoholic fatty liver disease (NAFLD) correlates with the high intake of fructose-rich soft drinks. Both inflammation and dysregulated iron metabolism are pathogenic factors in the development of NAFLD. The present investigation assessed the effects of a high-fructose diet (HF diet) on inflammation and iron metabolism. In this study, rats were fed a control or HF diet for 4, 8, or 12 weeks, after which insulin resistance, transaminases levels, serum and liver lipid profiles, inflammatory factors, and iron metabolism-related molecules were evaluated. The activities of the hepatic inflammation-associated pathways, IKKβ/NF-κB, and JAK2/STAT3, were detected by western blot. Result showed that the HF diet-fed animals developed a time-dependent serum lipid increase and hepatic lipid accumulation as well as insulin resistance. Serum iron (SI), serum ferritin (SF), and transferrin saturation (TS) decreased while total iron-binding capacity (TIBC) and serum transferrin (s-TF) increased at 8 and 12 weeks in the HF diet group. The HF diet led to increased transaminases levels at 8 and 12 weeks, and iron deposition was observed in the liver, accompanied by an upregulation of ferritin light chain (FTL), hepcidin (HEPC), transferrin (TF), transferrin receptor 1 (TfR1), iron regulatory protein 1 (IRP1), hemojuvelin (HJV), and divalent metal transporter 1 (DMT1). Moreover, ferroportin (FPN1) levels were downregulated, as expected from the increased HEPC. A progressive inflammation phenotype was apparent, with increased inflammatory factors, MDA, IL-1β, IL-6, and TNF-α, in the serum and liver tissue. Concomitantly, the hepatic IKKβ/NF-κB and JAK2/STAT3 pathways were activated. In summary, we verified that HF diet induces systemic iron deficiency and hepatic iron accumulation, likely due to the activation of inflammation via the NF-κB and JAK2/STAT3 pathways. PRACTICAL APPLICATIONS: As increasing numbers of individuals consume HF diets, the health implications of this type of over nutrition become globally relevant. Using a high-fructose diet rat model, our present study reveals inflammation as the link between a HF diet and dysregulated iron metabolism. Importantly, both inflammation and disrupted iron metabolism have been shown to be pathogenic factors in nonalcoholic fatty liver disease (NAFLD). The iron regulatory hormone, HEPC, is a link between the liver, inflammation, and iron metabolism. As fructose-rich foods become increasingly abundant and people's fructose intake increases, the impact of high fructose on health requires increased attention. Little research has been conducted on the effects of fructose on iron metabolism. Our study provides useful insights into the prevention and treatment of iron metabolism disorders arising from metabolic syndrome.
非酒精性脂肪性肝病(NAFLD)与富含果糖的软饮料摄入过高有关。炎症和铁代谢失调都是 NAFLD 发展的致病因素。本研究评估了高果糖饮食(HF 饮食)对炎症和铁代谢的影响。在这项研究中,大鼠喂食对照或 HF 饮食 4、8 或 12 周,然后评估胰岛素抵抗、转氨酶水平、血清和肝脏脂质谱、炎症因子和铁代谢相关分子。通过 Western blot 检测肝炎症相关途径 IKKβ/NF-κB 和 JAK2/STAT3 的活性。结果表明,HF 饮食喂养的动物表现出时间依赖性血清脂质增加和肝脂质蓄积以及胰岛素抵抗。血清铁(SI)、血清铁蛋白(SF)和转铁饱和度(TS)在 HF 饮食组 8 和 12 周时降低,而总铁结合能力(TIBC)和血清转铁蛋白(s-TF)增加。HF 饮食在 8 和 12 周时导致转氨酶水平升高,并且在肝脏中观察到铁沉积,伴随着铁蛋白轻链(FTL)、hepcidin(HEPC)、转铁蛋白(TF)、转铁蛋白受体 1(TfR1)、铁调节蛋白 1(IRP1)、hemojuvelin(HJV)和二价金属转运蛋白 1(DMT1)的上调。此外,预期由于 HEPC 的增加,亚铁转运蛋白(FPN1)水平下调。血清和肝组织中炎症因子、MDA、IL-1β、IL-6 和 TNF-α的增加表明存在进行性炎症表型。同时,肝 IKKβ/NF-κB 和 JAK2/STAT3 途径被激活。总之,我们验证了 HF 饮食诱导全身铁缺乏和肝铁蓄积,这可能是由于 NF-κB 和 JAK2/STAT3 途径激活引起的炎症。
随着越来越多的人食用 HF 饮食,这种营养过剩对全球健康的影响变得越来越重要。使用高果糖饮食大鼠模型,本研究揭示了炎症是 HF 饮食与铁代谢失调之间的联系。重要的是,炎症和铁代谢紊乱已被证明是非酒精性脂肪性肝病(NAFLD)的致病因素。铁调节激素 HEPC 是肝脏、炎症和铁代谢之间的联系。由于富含果糖的食物越来越丰富,人们的果糖摄入量增加,因此需要更多地关注高果糖对健康的影响。关于果糖对铁代谢的影响,研究甚少。我们的研究为代谢综合征引起的铁代谢紊乱的预防和治疗提供了有用的见解。