Abstract：
A 60-d feeding trial was conducted to explore the potential regulatory effects of dietary Clostridium butyricum cultures (CBC) supplementation in high-carbohydrate diet (HCD) on carbohydrate utilisation, antioxidant capacity and intestinal microbiota of largemouth bass. Triplicate groups of largemouth bass (average weight 35·03 ± 0·04 g), with a destiny of twenty-eight individuals per tank, were fed low-carbohydrate diet and HCD supplemented with different concentration of CBC (0 %, 0·25 %, 0·50 % and 1·00 %). The results showed that dietary CBC inclusion alleviated the hepatic glycogen accumulation induced by HCD intake. Additionally, the expression of hepatic ampkα1 and insulin signaling pathway-related genes (ira, irb, irs, p13kr1 and akt1) increased linearly with dietary CBC inclusion, which might be associated with the activation of glycolysis-related genes (gk, pfkl and pk). Meanwhile, the expression of intestinal SCFA transport-related genes (ffar3 and mct1) was significantly increased with dietary CBC inclusion. In addition, the hepatic antioxidant capacity was improved with dietary CBC supplementation, as evidenced by linear decrease in malondialdehyde concentration and expression of keap1, and linear increase in antioxidant enzyme activities (total antioxidative capacity, total superoxide dismutase and catalase) and expression of antioxidant enzyme-related genes (nrf2, sod1, sod2 and cat). The analysis of bacterial 16S rRNA V3-4 region indicated that dietary CBC inclusion significantly reduced the enrichment of Firmicutes and potential pathogenic bacteria genus Mycoplasma but significantly elevated the relative abundance of Fusobacteria and Cetobacterium. In summary, dietary CBC inclusion improved carbohydrate utilization, antioxidant capacity and intestinal microbiota of largemouth bass fed HCD.
摘要：
进行了60天的喂养试验，以探索高碳水化合物饮食（HCD）中饮食中补充丁酸梭菌培养物（CBC）对碳水化合物利用的潜在调节作用，大嘴鲈鱼的抗氧化能力和肠道菌群。一式三份大嘴鲈鱼组（平均体重35·03±0·04g），每个坦克有28个人的命运，饲喂低碳水化合物饮食和补充不同浓度CBC的HCD(0%，0·25%，0·50%和1·00%）。结果表明，膳食CBC包合减轻了HCD摄入引起的肝糖原积累。此外,肝ampkα1和胰岛素信号通路相关基因的表达(IRA，irb,irs,p13kr1和akt1)随饮食CBC含量线性增加，这可能与糖酵解相关基因的激活有关(gk，pfkl和pk)。同时,肠道SCFA转运相关基因(ffar3和mct1)的表达随着饮食CBC的加入而显著增加。此外,饮食中补充CBC可以提高肝脏的抗氧化能力，如丙二醛浓度和keap1表达的线性降低和抗氧化酶活性的线性增加(总抗氧化能力，总超氧化物歧化酶和过氧化氢酶）和抗氧化酶相关基因（nrf2，sod1，sod2和cat）的表达。对细菌16SrRNAV3-4区域的分析表明，饮食中的CBC掺入显着降低了Firmicutes和潜在致病菌支原体属的富集，但显着提高了Fusobacteria和Cetobacterium的相对丰度。总之,饮食中加入CBC提高了碳水化合物的利用率，大嘴鲈鱼饲喂HCD的抗氧化能力和肠道菌群。
