Abstract：
The effects of seaweed cellulose (SC) on high fat-sugar diet (HFSD)-induced glucolipid metabolism disorders in mice and potential mechanisms were investigated. SC was isolated from dealginated residues of giant kelp (Macrocystis pyrifera), with a crystallinity index of 85.51 % and an average particle size of 678.2 nm. Administering SC to C57BL/6 mice at 250 or 500 mg/kg BW/day via intragastric gavage for six weeks apparently inhibited the development of HFSD-induced obesity, dyslipidemia, insulin resistance, oxidative stress and liver damage. Notably, SC intervention partially restored the structure and composition of the gut microbiota altered by the HFSD, substantially lowering the Firmicutes to Bacteroidetes ratio, and greatly increasing the relative abundance of Lactobacillus, Bifidobacterium, Oscillospira, Bacteroides and Akkermansia, which contributed to improved short-chain fatty acid (SCFA) production. Supplementing with a higher dose of SC led to more significant increases in total SCFA (67.57 %), acetate (64.56 %), propionate (73.52 %) and butyrate (66.23 %) concentrations in the rectal contents of HFSD-fed mice. The results indicated that highly crystalline SC microparticles could modulate gut microbiota dysbiosis and ameliorate HFSD-induced obesity and related metabolic syndrome in mice. Furthermore, particle size might have crucial impact on the prebiotic effects of cellulose as insoluble dietary fiber.
摘要：
研究了海藻纤维素（SC）对高脂糖饮食（HFSD）诱导的小鼠糖脂代谢紊乱的影响及其可能的机制。SC是从巨型海带（大囊藻）的脱胶残留物中分离出来的，结晶度指数为85.51%,平均粒径为678.2nm。通过胃内灌胃以250或500mg/kg体重/天的剂量对C57BL/6小鼠施用SC六周明显抑制了HFSD诱导的肥胖的发展，血脂异常,胰岛素抵抗，氧化应激和肝损伤。值得注意的是,SC干预部分恢复了HFSD改变的肠道微生物群的结构和组成，大大降低了Firmicutes与拟杆菌的比率，大大增加了乳酸菌的相对丰度，双歧杆菌,螺旋体,拟杆菌和Akkermansia,这有助于改善短链脂肪酸（SCFA）的生产。补充较高剂量的SC导致总SCFA（67.57％）显着增加，醋酸盐（64.56%），HFSD喂养小鼠直肠内容物中的丙酸（73.52％）和丁酸（66.23％）浓度。结果表明，高度结晶的SC微粒可以调节肠道菌群失调，改善HFSD诱导的小鼠肥胖和相关的代谢综合征。此外，颗粒大小可能对纤维素作为不溶性膳食纤维的益生元效应有至关重要的影响。
