Identification of functional ingredients of wild rice and their potential mechanisms of maintaining physiologic function and integrity of the vessel wall

我建议进行一系列实验，以确定野生稻的功能成分，以及它们可能维持生理功能和维管壁完整性的潜在机制。在我之前的研究中，我观察到在转基因小鼠模型即低密度脂蛋白受体KO(LDL-r-KO)小鼠的饮食中添加野生大米与显著降低血浆胆固醇水平和维持主要冠状动脉和主动脉的正常形态有关。我们知道，与传统白米相比，野生大米含有更多的膳食纤维。膳食纤维可能有助于野生大米的降胆固醇特性。然而，低密度脂蛋白-胆固醇水平的降低幅度大于膳食纤维本身的预期。野生大米的其他成分可能也有助于降低胆固醇的效果，从而维持正常的血管结构和功能。我建议利用低密度脂蛋白-r-KO和载脂蛋白E-KO小鼠以及适当的细胞系进行一系列分析实验，以鉴定野生大米的生物活性成分。我还建议调查长期食用野生大米对这些动物肠道微生物区系的影响。野生大米可以被认为是益生菌。一些研究报告说，肠道微生物区系类型和种群的变化可能与短链脂肪酸等生物活性化合物形成的变化有关。这些化合物还可以有益地改变细胞的脂肪代谢，从而降低血清胆固醇水平。这些动物的组织和血浆样本将被筛选，以鉴定生物活性物质，如生育酚、生育三烯醇、伽马-谷维素、阿魏酸和植物甾醇。这些物质的浓度将与他们的饮食水平和血管壁的完整性状态以及炎症和血脂水平的生物标志物相关。在确定野生大米生物活性成分的内部剂量后，这些物质将在两种动物模型(低密度脂蛋白-r-KO和载脂蛋白E-KO)小鼠以及Hep G2和Caco-2细胞系中单独或联合进行测试。此外，将测试单核细胞与治疗动物的主动脉内皮细胞或用测试化合物处理的人脐静脉内皮细胞的粘附性。拟议的研究将产生的数据将有助于了解膳食制剂如何帮助维持生物系统的完整性；这将支持开发和销售对加拿大农业和经济部门产生重大影响的新的功能食品和/或营养食品。在此期间，我将培训20名不同层次的实习生，包括本科生(10名)和研究生(3名博士+4名硕士+2名访问博士)学生和1名博士后研究员。

I propose to perform a series of experiments to identify functional ingredients of wild rice and the potential mechanisms by which they may maintain physiologic function and integrity of the vessel wall. In my previous studies, I observed that addition of wild rice to the diets of a genetically-modified mouse model, namely LDL-receptor-KO (LDL-r-KO) mice, was associated with significant reductions in plasma cholesterol levels and maintaining normal morphology of the major coronary arteries and aorta. We know that wild rice contains higher amounts of dietary fiber as compared to the conventional white rice. Dietary fiber may have contributed to the cholesterol-lowering properties of wild rice. However, the extent of reductions in LDL-cholesterol levels was greater than what is expected from dietary fiber per se. Other ingredients of wild rice may have also contributed to the cholesterol-lowering effects and consequently maintaining normal vessel structure and function. I propose to carry out a series of analytical experiments to identify bio-active components of wild rice using the LDL-r-KO and apo E-KO mice as well as appropriate cell lines. I also propose to investigate the impact of long-term consumption of wild rice on the gut micro-flora in these animals. Wild rice may be considered as a prebiotic. Several studies have reported that changes in the type and population of the gut micro-flora may be associated with changes in the formation of biologically active compounds such as short chain fatty acids. These compounds may also beneficially alter cellular lipid metabolism, resulting in reduced serum cholesterol levels. Tissue and plasma samples from these animals will be screened for identification of biologically active substances such as tocopherols, tocotrienols, gamma-oryzanols, ferulic acid and plant sterols. Concentrations of these substances will be correlated with their dietary levels and the state of integrity of the vessel wall plus the biomarkers of inflammation and plasma lipid levels. After establishing the internal doses of the bio-active ingredients of the wild rice, these substances will be tested individually or in combination in both animal models (LDL-r-KO and apo E-KO) mice as well as Hep G2 and Caco-2 cell lines. Additionally, the adhesion of monocytes to the aortic endothelial cells from the treated animals or from the human umbilical vein endothelial cells treated with the test compounds will be tested. The proposed studies will produce data that will shed light on understanding how dietary agents help maintaining the integrity of biological systems; this endorses developing and marketing new functional foods and/or nutraceuticals with a great impact on the Canadian Agriculture and Economy sectors. During this grant, I will train 20 trainees at various levels including undergraduate (10) and graduate (3 PhD + 4 MSc + 2 visiting PhD) students and one post-doctoral fellow.**