基于代谢组学和肠道微生态的核桃多酚降脂物质基础及作用机制研究

Hyperlipidemia has significantly increased in China in recent years. Application of natural plants and their active ingredients for lipid-lowering has become one of R&D hotspots all over the world. Walnut kermel is the traditional Chinese medicine pharmacopoeia included, but its medicinal value has ineffectively been researched and developed. Our previous studies have shown that polyphenol-rich extracts from walnut present good hypolipidemic effects on diet-induced hyperlipidemia model rats, MSG-induced hyperlipidemia mice, mice induced by yolk milk. Walnut cultivation area and yield of China rank first in the world, and Yunnan walnuts occupy the top of China. This project intends to further using animal models, metabolomics and gut microbiome, combining with the pharmacodynamics and bioinformatics,so as to systematically research metabonomics and gut microbiome of a high-fat diet and hyperlipidemia model rats before and after walnut polyphenols intervention, for which illuminate lipid-lowering active metabolites related targets, metabolic profile, gut microbiota, lipid-lowering active ingredient or component group and corresponding metabolism and function in the body,as well as evaluate walnut polyphenols effect of prevention and treatment of hyperlipidemia, reveal material basis and mechanism of walnut polyphenols lipid-lowering based on the overall animal metabolism and intestinal flora level. The results will lay the scientific bases for enriching the content of science of pharmacopoeia walnut items, elevating walnut medicinal value, and further exploring hyperlipidemia and hypolipidemia metabonomics and gut microbiome.

近年高脂血症发病率持续上升，利用天然植物及其有效成分降脂是国内外的研究热点。核桃是药典收录的传统中药，但其药用价值尚未得到有效研发。我们前期研究表明核桃富含多酚，核桃多酚对高脂血症大鼠和高脂血症小鼠均有良好的降脂作用。我国核桃种植面积和产量均居世界第一，云南又居全国之首。本项目拟进一步采用动物模型、代谢组学和肠道菌群组学的研究技术和方法，结合药效学和生物信息学，系统研究高脂饮食和高脂血症模型大鼠及其核桃多酚干预前后的代谢组学和肠道菌群组学，阐明与降脂活性相关的代谢物靶标、代谢轮廓、肠道菌群、降脂活性成分或成分群及其在体内的代谢和作用，同时评估核桃多酚预防和治疗高脂血症的效果，从整体动物体内代谢和肠道菌群层面揭示核桃多酚降脂的物质基础和作用机制，为提升核桃药用价值和核桃资源的高效利用及其辅助降脂奠定科学基础，并丰富药典核桃条目的科学内涵，丰富高脂血症及其降脂代谢组学和肠道菌群组学的科学内容。

高脂血症发病率持续上升，植物多酚降脂是其研究热点之一。核桃富含多酚，云南核桃面积产量均居全国第一，资源丰富。本项目利用高脂饮食诱导的高脂血症大鼠模型，探明了核桃多酚(WMP)对高脂饮食引起的高脂血症有显著的预防和治疗作用，能显著抑制高脂饮食引起的大鼠血清和肝脏中TC､TG､LDL-C水平、体重、Lee’s指数、AST、ALT、和MDA的升高，显著提高HDL-C、CAT､GSH和ADP，visfatin和PPAR-γ及脂肪酶HSL的表达和降低血清LEP的表达。探明了WMP降脂的活性成分和成分群，其中相对含量高的Glansreginin A降脂关联度最高，其次是Glansreginin B､(4S)-4-羟-α-四氢萘酮-4-O-β-D-(6’-O-4”羟苯甲酰)-G､芦丁等成分。用代谢组学探明了WMP在预防高脂血症方面有苯乙酰甘氨酸等血清代谢标志物12种、肝脏代谢标志物11种，主要涉及的代谢通路为芳香族氨基酸合成等；在治疗高脂血症方面可显著逆转苯乙酰甘氨酸等血清中32种代谢标志物和肝脏中23种代谢标志物的显著变化，主要涉及的代谢通路为牛磺酸和亚牛磺酸的代谢，探明了WMP防治高血脂症代谢物靶标及其调控途径和代谢通路。用肠道菌群组学探明了WMP对高脂饮食和高脂血症模型大鼠肠道菌群的影响及其变化规律，WMP干预可逆转由于高脂饮食和高脂血症引起的肠道菌群失调，恢复肠道菌群多样性，降低革兰氏阴性菌等有害菌的丰度，增加短链脂肪酸产生菌等益生菌的丰度。用转录组学筛选出WMP降脂的6个关键基因Cpt1a、Por、Chka、Apoa1、Hadhb、Scd。用网络药理学获得核桃粕中槲皮素､芦丁､儿茶素等7种成分具有降脂相关靶点59个，节点值最高的靶点为透明质酸合酶2､核受体辅活化因子2､雌激素受体､过氧化氢酶､雄激素受体､血管内皮生长因子A，主要信号通路为HIF-1信号通路､TNF信号通路｡项目从整体动物体内代谢和肠道菌群等层面揭示了核桃多酚降脂的物质基础和作用机制，为提升核桃药用价值和核桃资源的高效利用及其辅助降脂奠定科学基础。项目实施期间发表相关论文9篇(含中科院SCI一区刊物3篇），申请发明专利3件，获授权发明专利1件。