Section of Nutrition and Dietetics, Division of Medicine, Department of Clinical Service, Oslo University Hospital, Oslo, Norway.
Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
Eur J Nutr. 2020 Oct;59(7):3325-3338. doi: 10.1007/s00394-020-02282-5. Epub 2020 May 21.
Compared to a healthy population, the gut microbiota in type 2 diabetes presents with several unfavourable features that may impair glucose regulation. The aim of this study was to evaluate the prebiotic effect of inulin-type fructans on the faecal microbiota and short-chain fatty acids (SCFA) in patients with type 2 diabetes.
The study was a placebo controlled crossover study, where 25 patients (15 men) aged 41-71 years consumed 16 g of inulin-type fructans (a mixture of oligofructose and inulin) and 16-g placebo (maltodextrin) for 6 weeks in randomised order. A 4-week washout separated the 6 weeks treatments. The faecal microbiota was analysed by high-throughput 16S rRNA amplicon sequencing and SCFA in faeces were analysed using vacuum distillation followed by gas chromatography.
Treatment with inulin-type fructans induced moderate changes in the faecal microbiota composition (1.5%, p = 0.045). A bifidogenic effect was most prominent, with highest positive effect on operational taxonomic units (OTUs) of Bifidobacterium adolescentis, followed by OTUs of Bacteroides. Significantly higher faecal concentrations of total SCFA, acetic acid and propionic acid were detected after prebiotic consumption compared to placebo. The prebiotic fibre had no effects on the concentration of butyric acid or on the overall microbial diversity.
Six weeks supplementation with inulin-type fructans had a significant bifidogenic effect and induced increased concentrations of faecal SCFA, without changing faecal microbial diversity. Our findings suggest a moderate potential of inulin-type fructans to improve gut microbiota composition and to increase microbial fermentation in type 2 diabetes.
The trial is registered at clinicaltrials.gov (NCT02569684).
与健康人群相比，2 型糖尿病患者的肠道微生物群存在多种不利特征，可能会损害葡萄糖调节。本研究旨在评估菊粉型果聚糖对 2 型糖尿病患者粪便微生物群和短链脂肪酸（SCFA）的益生元作用。
该研究是一项安慰剂对照交叉研究，25 名（15 名男性）年龄在 41-71 岁的患者随机分为两组，分别服用 16 克菊粉型果聚糖（低聚果糖和菊粉的混合物）和 16 克安慰剂（麦芽糊精），持续 6 周。4 周洗脱期将 6 周的治疗分开。通过高通量 16S rRNA 扩增子测序分析粪便微生物群，使用真空蒸馏和气相色谱法分析粪便中的 SCFA。
菊粉型果聚糖治疗引起粪便微生物群组成的中度变化（1.5%，p=0.045）。双歧杆菌作用最为明显，双歧杆菌属的操作分类单位（OTUs）的正效应最高，其次是拟杆菌属的 OTUs。与安慰剂相比，益生元后粪便中总 SCFA、乙酸和丙酸的浓度显著升高。该益生元纤维对丁酸浓度或整体微生物多样性没有影响。
6 周补充菊粉型果聚糖具有显著的双歧杆菌作用，并诱导粪便 SCFA 浓度增加，而不改变粪便微生物多样性。我们的研究结果表明，菊粉型果聚糖具有适度的潜力，可以改善肠道微生物群组成，并增加 2 型糖尿病患者的微生物发酵。
该试验在 clinicaltrials.gov 注册（NCT02569684）。
