Zhu Qian, Wu Jingjing, Li Jianling, Wang Shengquan, He Daxue, Lian Xuemei
Key Laboratory of Molecular Biology for Infectious Diseases, Ministry of Education, Center for Lipid Research, Chongqing Medical University, Chongqing, China.
Department of Nutrition and Food Hygiene, School of Public Health and Management, Chongqing Medical University, Chongqing, China.
Front Nutr. 2022 Jul 27;9:924236. doi: 10.3389/fnut.2022.924236. eCollection 2022.
This study aimed to investigate the long-term effects of phytosterols (PS) intake on systemic and tissue-specific lipid metabolism in C57BL/6J mice. Healthy male C57BL/6J mice were randomly divided into control diet group (CS) and PS diet group (2% PS). After 28 weeks of continuous feeding, serums, livers, and lungs were collected for targeted free sterols quantification, biochemical tests, lipid profile detection, and RNA-seq analysis. Compared with the CS group, 2% PS supplementation significantly increased campesterol concentrations and its ratio to cholesterol in the serum, liver, and lung of mice, with cholestanol concentrations and its ratio to cholesterol decreased. Total cholesterol (TC) levels were reduced in the serum of the PS group ( < 0.05), with the triglyceride (TG) levels unchanged. In response to the decreased circulating cholesterol concentration, the expression of endogenous cholesterol synthesis genes was upregulated in the liver, but caused no obvious lipid accumulation and inflammatory cell infiltration. However, for peripheral tissues, long-term PS-fed mice exhibited diminished cholesterol synthesis, fatty acid transport, and oxidation in the lung. The results provided clear indication that 2% PS diet effectively reduced circulating TC levels in the healthy mice, with tissue-specific lipid metabolic regulation in the liver and the lung.
本研究旨在探讨摄入植物甾醇（PS）对C57BL/6J小鼠全身及组织特异性脂质代谢的长期影响。将健康雄性C57BL/6J小鼠随机分为对照饮食组（CS）和PS饮食组（2%PS）。连续喂养28周后，收集血清、肝脏和肺组织进行靶向游离甾醇定量、生化检测、血脂谱检测及RNA测序分析。与CS组相比，补充2%PS显著提高了小鼠血清、肝脏和肺组织中菜油甾醇的浓度及其与胆固醇的比值，而胆甾烷醇浓度及其与胆固醇的比值降低。PS组血清总胆固醇（TC）水平降低（<0.05），甘油三酯（TG）水平无变化。随着循环胆固醇浓度降低，肝脏中内源性胆固醇合成基因的表达上调，但未引起明显的脂质蓄积和炎性细胞浸润。然而，对于外周组织，长期喂食PS的小鼠肺组织中胆固醇合成、脂肪酸转运及氧化减少。结果表明，2%PS饮食可有效降低健康小鼠的循环TC水平，并对肝脏和肺组织进行组织特异性脂质代谢调节。
