Teagasc Moorepark Food Research Centre, Fermoy, Co. Cork, Ireland.
Department of Microbiology, University College Cork, National University of Ireland, Co. Cork, Ireland.
Microbiology (Reading). 2011 Feb;157(Pt 2):609-615. doi: 10.1099/mic.0.043406-0. Epub 2010 Dec 22.
We have previously demonstrated that oral administration of a metabolically active Bifidobacterium breve strain, with ability to form cis-9, trans-11 conjugated linoleic acid (CLA), resulted in modulation of the fatty acid composition of the host, including significantly elevated concentrations of c9, t11 CLA and omega-3 (n-3) fatty acids in liver and adipose tissue. In this study, we investigated whether a recombinant lactobacillus expressing linoleic acid isomerase (responsible for production of t10, c12 CLA) from Propionibacterium acnes (PAI) could influence the fatty acid composition of different tissues in a mouse model. Linoleic-acid-supplemented diets (2 %, w/w) were fed in combination with either a recombinant t10, c12 CLA-producing Lactobacillus paracasei NFBC 338 (Lb338), or an isogenic (vector-containing) control strain, to BALB/c mice for 8 weeks. A third group of mice received linoleic acid alone (2 %, w/w). Tissue fatty acid composition was assessed by GLC at the end of the trial. Ingestion of the strain expressing linoleic acid isomerase was associated with a 4-fold increase (P<0.001) in t10, c12 CLA in adipose tissues of the mice when compared with mice that received the isogenic non-CLA-producing strain. The livers of the mice that received the recombinant CLA-producing Lb338 also contained a 2.5-fold (albeit not significantly) higher concentration of t10, c12 CLA, compared to the control group. These data demonstrate that a single gene (encoding linoleic acid isomerase) expressed in an intestinal microbe can influence the fatty acid composition of host fat.
我们之前已经证明，口服具有形成顺式-9，反式-11 共轭亚油酸（CLA）能力的代谢活跃短双歧杆菌菌株会调节宿主的脂肪酸组成，包括肝和脂肪组织中 c9、t11 CLA 和 ω-3（n-3）脂肪酸的浓度显著升高。在这项研究中，我们研究了来自痤疮丙酸杆菌（PAI）的表达亚油酸异构酶（负责生产 t10、c12 CLA）的重组乳杆菌是否可以影响不同组织在小鼠模型中的脂肪酸组成。用亚油酸补充饮食（2%，w/w）与重组 t10、c12 CLA 产生乳杆菌副干酪亚种 NFBC 338（Lb338）或同基因（含载体）对照菌株联合喂养 BALB/c 小鼠 8 周。第三组小鼠单独接受亚油酸（2%，w/w）。试验结束时通过 GLC 评估组织脂肪酸组成。与接受同基因非 CLA 产生菌株的小鼠相比，摄入表达亚油酸异构酶的菌株可使脂肪组织中 t10、c12 CLA 增加 4 倍（P<0.001）。接受重组 CLA 产生 Lb338 的小鼠的肝脏中也含有 t10、c12 CLA 的浓度增加了 2.5 倍（尽管没有显著增加）与对照组相比。这些数据表明，肠道微生物中表达的单个基因（编码亚油酸异构酶）可以影响宿主脂肪的脂肪酸组成。
