【摘要】 目的 研究粪菌定植对无菌SD大鼠脂肪吸收率、脂肪酸代谢流向及短链脂肪酸产量的影响。方法 将10周龄雄性无菌SD大鼠按体重随机分为4组(每组5～6只),空白对照组灌胃生理盐水喂饲无菌鼠基础饲料，正常甘油三酯(triglyceride, TG)组定植TG正常(≤1.7 mmol/L)人群肠道菌群喂饲无菌鼠基础饲料，另两组定植高TG(>1.7 mmol/L)人群肠道菌群分别喂饲无菌鼠基础饲料和高脂饲料(脂肪供能比40.5%)。将首次定植当日设为第0天(实验计时起点),于第0、2、4天按每100克体重1 mL灌胃粪便菌液。适应10天后，第14天起对高脂干预组喂饲高脂饲料共9周。分别于第0(定植前)、14(喂饲高脂饲料前)、21、56和77天刺激大鼠肛门诱导排便并无菌采集，测定总脂肪以计算脂肪吸收率，测定脂肪酸谱和丁酸等短链脂肪酸。结果 第77天，与空白对照组相比，正常TG组体重和脂肪吸收率、粪便中棕榈油酸和亚油酸水平显著降低(P<0.05),而丁酸、棕榈酸、花生酸、油酸、二十二碳六烯酸(DHA)、硬脂酸水平显著升高(P<0.05)。高TG组体重和脂肪吸收率、粪便中棕榈油酸和亚油酸排出水平显著高于正常TG组(P<0.05),丁酸、3种饱和脂肪酸及油酸排出水平则显著降低(P<0.05)。高脂干预组大鼠的体重、脂肪吸收率及粪便中各脂肪酸水平均显著高于高TG组(P<0.05)。第21天后，所有组均未检出α-亚麻酸。结论 正常TG菌群定植可积极调节无菌大鼠脂代谢，高TG菌群定植会打破脂代谢平衡，抑制饱和脂肪酸与油酸排出、减少丁酸生成，提高脂肪吸收率，增加肥胖风险，并且可能与高脂饲料协同作用，加重肠道脂代谢紊乱。更多还原

【Abstract】 OBJECTIVE To investigate the effects of fecal microbiota transplantation on fat absorption rate, fatty acid metabolic flux, and short-chain fatty acid production in germ-free Sprague-Dawley(SD) rats.METHODS Ten-week-old male germ-free SD rats were randomly grouped(5-6 rats/group) by body weight. Blank control: saline gavaged + germ-free basal diet. Normal control: colonized with normal-TG(≤1.7 mmol/L) human gut microbiota + germ-free basal diet. Two other groups: colonized with high-TG(>1.7 mmol/L) human gut microbiota, one on germ-free basal diet and the other on high-fat diet(40.5% fat energy). Day 0 marked colonization start. On Days 0, 2, 4, rats were gavaged with fecal bacteria(1 mL/100 g body weight). After 10-day adaptation, high-fat group started high-fat diet on Day 14. Feces were induced and collected aseptically on Days 0, 14, 21, 56, 77 for total fat(fat absorption rate), fatty acid profile, and short-chain fatty acids like butyric acid.RESULTS On Day 77, compared to blank control, normal control had lower body weight, fat absorption rate, and fecal palmitoleic and linoleic acids(P<0.05), but higher butyric, palmitic, arachidic, oleic, DHA, and stearic acids(P<0.05). High-TG group had higher body weight, fat absorption rate, and fecal palmitoleic and linoleic acids than normal control(P<0.05), with lower butyric, three saturated, and oleic acids(P<0.05). High-fat group had higher body weight, fat absorption rate, and fecal fatty acids than high-TG group(P<0.05). After Day 21, α-linolenic acid was undetectable in all groups.CONCLUSION In contrast to the positive regulation of lipid metabolism in rats by colonization with non-high-TG microbiota, colonization with high-TG microbiota disrupts lipid metabolism balance, inhibits the excretion of saturated fatty acids and oleic acid, reduces butyrate production, increases fat absorption rate, elevates the risk of obesity, and may synergize with a high-fat diet to exacerbate intestinal lipid metabolism disorders.更多还原