Human Biology, School for Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University Medical Center+, Maastricht, The Netherlands.
Laboratory of Microbiology, Wageningen University&Research, Wageningen, The Netherlands.
Gut Microbes. 2022 Jan-Dec;14(1):2009297. doi: 10.1080/19490976.2021.2009297.
Infusions of the short-chain fatty acid (SCFA) acetate in the distal colon improved metabolic parameters in men. Here, we hypothesized that combining rapidly and slowly fermentable fibers will enhance distal colonic acetate production and improve metabolic health. In vitro cultivation studies in a validated model of the colon were used to identify fiber mixtures that yielded high distal colonic acetate production. Subsequently, in two randomized crossover studies, lean and prediabetic overweight/obese men were included. In one study, participants received supplements of either long-chain inulin+resistant starch (INU+RS), INU or maltodextrin (PLA) the day prior to a clinical investigation day (CID). The second trial studied beta glucan+RS (BG+RS) versus BG and PLA. During each CID, breath hydrogen, indirect calorimetry, plasma metabolites/hormones were assessed during fasting and postprandial conditions. Additionally, fecal microbiota composition and SCFA were determined. In prediabetic men, INU+RS increased plasma acetate compared to INU or PLA ( < .05), but did not affect metabolic parameters. In lean men, INU+RS increased breath hydrogen and fasting plasma butyrate, which was accompanied by increased energy expenditure, carbohydrate oxidation and PYY and decreased postprandial glucose concentrations (all < .05) compared to PLA. BG+RS increased plasma butyrate compared to PLA ( < .05) in prediabetic individuals, but did not affect other fermentation/metabolic markers in both phenotypes. Fiber-induced shifts in fecal microbiota were individual-specific and more pronounced with INU+RS versus BG+RS. Administration of INU+RS (not BG+RS) the day prior to investigation improved metabolic parameters in lean but not in prediabetic individuals, demonstrating that effects were phenotype- and fiber-specific. Further research should study whether longer-term supplementation periods are required to elicit beneficial metabolic health in prediabetic individuals. Trial registration numbers: Clinical trial No. NCT03711383 (Inulin study) and Clinical trial No. NCT03714646 (Beta glucan study).
在远端结肠输注短链脂肪酸（SCFA）乙酸盐可改善男性的代谢参数。在这里，我们假设将快速发酵和缓慢发酵的纤维结合起来可以提高远端结肠乙酸盐的产生，并改善代谢健康。我们使用经过验证的结肠模型进行体外培养研究，以确定产生高远端结肠乙酸盐产量的纤维混合物。随后，在两项随机交叉研究中纳入了瘦人和前驱糖尿病超重/肥胖男性。在一项研究中，参与者在前一天接受了长链菊粉+抗性淀粉（INU+RS）、INU 或麦芽糊精（PLA）的补充剂，然后进行临床研究日（CID）。第二项试验研究了β葡聚糖+RS（BG+RS）与 BG 和 PLA 的对比。在每个 CID 期间，评估禁食和餐后条件下的呼吸氢、间接热量测定法、血浆代谢物/激素，此外还测定了粪便微生物群落组成和 SCFA。在前驱糖尿病男性中，INU+RS 与 INU 或 PLA 相比增加了血浆乙酸盐（<0.05），但对代谢参数没有影响。在瘦男性中，INU+RS 增加了呼吸氢和空腹时的血浆丁酸盐，这伴随着能量消耗增加、碳水化合物氧化和 PYY 增加以及餐后葡萄糖浓度降低（所有<0.05）与 PLA 相比。与 PLA 相比，BG+RS 增加了前驱糖尿病个体的血浆丁酸（<0.05），但对两种表型的其他发酵/代谢标志物没有影响。纤维诱导的粪便微生物群变化具有个体特异性，与 INU+RS 相比，BG+RS 的变化更为明显。在调查前一天给予 INU+RS（而非 BG+RS）可改善瘦男性的代谢参数，但不能改善前驱糖尿病男性的代谢参数，这表明作用具有表型和纤维特异性。进一步的研究应该研究是否需要更长时间的补充期才能在前驱糖尿病个体中引起有益的代谢健康。临床试验注册号：临床试验号 NCT03711383（菊粉研究）和临床试验号 NCT03714646（β葡聚糖研究）。
