Guelph Food Research Centre, Agriculture and Agri-Food Canada (AAFC), Guelph, Ontario, Canada; Department of Human Health and Nutritional Science, University of Guelph, Guelph, Ontario, Canada;
Guelph Food Research Centre, Agriculture and Agri-Food Canada (AAFC), Guelph, Ontario, Canada;
Am J Physiol Gastrointest Liver Physiol. 2014 Jun 15;306(12):G1042-55. doi: 10.1152/ajpgi.00253.2013. Epub 2014 Apr 24.
Flaxseed (FS), a dietary oilseed, contains a variety of anti-inflammatory bioactives, including fermentable fiber, phenolic compounds (lignans), and the n-3 polyunsaturated fatty acid (PUFA) α-linolenic acid. The objective of this study was to determine the effects of FS and its n-3 PUFA-rich kernel or lignan- and soluble fiber-rich hull on colitis severity in a mouse model of acute colonic inflammation. C57BL/6 male mice were fed a basal diet (negative control) or a basal diet supplemented with 10% FS, 6% kernel, or 4% hull for 3 wk prior to and during colitis induction via 5 days of 2% (wt/vol) dextran sodium sulfate (DSS) in their drinking water (n = 12/group). An increase in anti-inflammatory metabolites (hepatic n-3 PUFAs, serum mammalian lignans, and cecal short-chain fatty acids) was associated with consumption of all FS-based diets, but not with anti-inflammatory effects in DSS-exposed mice. Dietary FS exacerbated DSS-induced acute colitis, as indicated by a heightened disease activity index and an increase in colonic injury and inflammatory biomarkers [histological damage, apoptosis, myeloperoxidase, inflammatory cytokines (IL-6 and IL-1β), and NF-κB signaling-related genes (Nfkb1, Ccl5, Bcl2a1a, Egfr, Relb, Birc3, and Atf1)]. Additionally, the adverse effect of the FS diet was extended systemically, as serum cytokines (IL-6, IFNγ, and IL-1β) and hepatic cholesterol levels were increased. The adverse effects of FS were not associated with alterations in fecal microbial load or systemic bacterial translocation (endotoxemia). Collectively, this study demonstrates that although consumption of a 10% FS diet enhanced the levels of n-3 PUFAs, short-chain polyunsaturated fatty acids, and lignans in mice, it exacerbated DSS-induced colonic injury and inflammation.
亚麻籽（FS）是一种食用性油籽，含有多种抗炎生物活性物质，包括可发酵纤维、酚类化合物（木脂素）和 n-3 多不饱和脂肪酸（PUFA）α-亚麻酸。本研究旨在确定 FS 及其富含 n-3PUFA 的内核，或富含木脂素和可溶性纤维的种皮，对急性结肠炎症小鼠模型中结肠炎严重程度的影响。C57BL/6 雄性小鼠在结肠炎诱导前和诱导期间，用基础饮食（阴性对照）或基础饮食补充 10%FS、6%内核或 4%种皮喂养 3 周，在饮用水中添加 5 天 2%（wt/vol）葡聚糖硫酸钠（DSS）（n=12/组）。所有 FS 基饮食均与抗炎代谢物（肝内 n-3PUFA、血清哺乳动物木脂素和盲肠短链脂肪酸）的增加相关，但与 DSS 暴露小鼠的抗炎作用无关。FS 饮食加重了 DSS 诱导的急性结肠炎，表现为疾病活动指数升高，结肠损伤和炎症生物标志物增加[组织学损伤、凋亡、髓过氧化物酶、炎症细胞因子（IL-6 和 IL-1β）和 NF-κB 信号相关基因（Nfkb1、Ccl5、Bcl2a1a、Egfr、Relb、Birc3 和 Atf1）]。此外，FS 饮食的不良影响还扩展到了全身，表现为血清细胞因子（IL-6、IFNγ 和 IL-1β）和肝胆固醇水平升高。FS 的不良影响与粪便微生物负荷或全身细菌易位（内毒素血症）的改变无关。总之，本研究表明，尽管 10%FS 饮食可增加小鼠体内 n-3PUFA、短链多不饱和脂肪酸和木脂素的水平，但会加重 DSS 诱导的结肠损伤和炎症。
