Hazarika Ankita, Kalita Himadri, Kalita Mohan Chandra, Devi Rajlakshmi
Life Sciences Division, Institute of Advanced Study in Science and Technology, Guwahati, Assam, India.
Department of Biotechnology, Gauhati University, Guwahati, Assam, India.
Nutrition. 2017 Jun;38:95-101. doi: 10.1016/j.nut.2017.01.005. Epub 2017 Feb 2.
The "lipid hypothesis" determined that saturated fatty acid (SFA) raises low-density lipoprotein cholesterol, thereby increasing the risk for metabolic syndrome (MetS). The aim of this study was to investigate the effect of subchronic withdrawal from a high-carbohydrate, high-saturated fat (HCHF) diet during MetS with reference to changes in deleterious SFA (C12:0, lauric acid; C14:0, myristic acid; C16:0, palmitic acid; C18:0, stearic acid) distribution in liver, white adipose tissue (WAT), and feces.
MetS induced by prolonged feeding of an HCHF diet in Wistar albino rat is used as a model of human MetS. The MetS-induced rats were withdrawn from the HCHF diet and changed to a basal diet for final 4 wk of the total experimental duration of 16 wk. SFA distribution in target tissues and hepatic low-density lipoprotein receptor (LDLr) expression were analyzed.
Analyses of changes in SFA concentration of target tissues indicate that C16:0 and C18:0 reduced in WAT and liver after withdrawal of the HCHF diet. There was a significant (P < 0.001) decrease in fecal C12:0 with HCHF feeding, which significantly (P < 0.01) increased after withdrawal of this diet. Also, an improvement in expression of hepatic LDLr was observed after withdrawal of HCHF diet.
The prolonged consumption of an HCHF diet leads to increased SFA accumulation in liver and WAT, decreased SFA excretion, and reduced hepatic LDLr expression during MetS, which is prominently reversed after subchronic withdrawal of the HCHF diet. This can contribute to better understanding of the metabolic fate of dietary SFA during MetS and may apply to the potential reversal of complications by the simple approach of nutritional modification.
“脂质假说”认为饱和脂肪酸(SFA)会升高低密度脂蛋白胆固醇,从而增加代谢综合征(MetS)的风险。本研究旨在探讨在代谢综合征期间,从高碳水化合物、高饱和脂肪(HCHF)饮食中进行亚慢性撤食对肝脏、白色脂肪组织(WAT)和粪便中有害饱和脂肪酸(C12:0,月桂酸;C14:0,肉豆蔻酸;C16:0,棕榈酸;C18:0,硬脂酸)分布变化的影响。
通过长期给Wistar白化大鼠喂食HCHF饮食诱导的MetS用作人类MetS的模型。将MetS诱导的大鼠从HCHF饮食中撤食,并在为期16周的总实验持续时间的最后4周改为基础饮食。分析目标组织中的饱和脂肪酸分布和肝脏低密度脂蛋白受体(LDLr)表达。
对目标组织饱和脂肪酸浓度变化的分析表明,撤掉HCHF饮食后,WAT和肝脏中的C16:0和C18:0减少。喂食HCHF饮食后,粪便C12:0显著降低(P < 0.001),撤掉该饮食后显著增加(P < 0.01)。此外,撤掉HCHF饮食后观察到肝脏LDLr表达有所改善。
长期食用HCHF饮食会导致代谢综合征期间肝脏和WAT中饱和脂肪酸积累增加、饱和脂肪酸排泄减少以及肝脏LDLr表达降低,在亚慢性撤掉HCHF饮食后这些情况会明显逆转。这有助于更好地理解代谢综合征期间膳食饱和脂肪酸的代谢归宿,并且可能适用于通过简单的营养调整方法潜在逆转并发症。