State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, P. R. China.
The Center of Gerontology and Geriatrics, National Clinical Research Center of Geriatrics, West China Hospital, Sichuan University, Chengdu, P. R. China.
BMC Microbiol. 2021 Feb 15;21(1):47. doi: 10.1186/s12866-021-02103-7.
Gut microbiota is critical in maintaining human health, of which diversity and abundance are subject to significantly reduce in seniors. Gut microbiota is reported to be stable across the long adulthood in general, but lack of careful examination, especially for the midlife people.
To characterize the gut microbiota in midlife, we investigated the faecal microbiota between two groups of healthy people, young, 20-39 years old, n = 15; and midlife, 40-60 years old, n = 15. Metabolic responses of the microbiota were studied through in vitro batch fermentation model. Although no difference was observed in the diversity indices between the two age groups, a wide range taxonomic changes were found in the faecal microbiota. Furthermore, substantial Bifidobacterium reduction was also found in both faecal and fermented samples. The faecal SCFAs are similar in both groups, as well as starch fermentation broth. However, after inulin fermentation, the acetate concentration and inulin degradation rate decreased while the gas production increased in midlife group, suggesting a deficiency of saccharolytic potential in midlife, especially for non-digestible carbohydrate.
Our data demonstrate that gut microbiota begins to change as early as in midlife. The reduction in Bifidobacterium dominates the change of the microbiota composition in midlife resulting in attenuated saccharolytic capacity of inulin, possibly leading to insufficient acetate production which might be associated with healthy problems in this transition period from young to elderly.
肠道微生物群对于维持人类健康至关重要，其多样性和丰度在老年人中显著降低。据报道，肠道微生物群在整个成年期通常是稳定的，但缺乏仔细的检查，特别是对于中年人群。
为了描述中年人的肠道微生物群，我们调查了两组健康人群的粪便微生物群，一组为年轻人，年龄 20-39 岁，n=15；另一组为中年人，年龄 40-60 岁，n=15。通过体外批量发酵模型研究了微生物群的代谢反应。尽管两个年龄组之间的多样性指数没有差异，但粪便微生物群存在广泛的分类变化。此外，粪便和发酵样本中双歧杆菌的数量也明显减少。两组粪便 SCFAs 相似，淀粉发酵液也是如此。然而，在菊粉发酵后，中年组的乙酸浓度和菊粉降解率降低，而气体产量增加，这表明中年组的糖解潜力不足，尤其是对不可消化的碳水化合物。
我们的数据表明，肠道微生物群早在中年就开始发生变化。双歧杆菌的减少主导了中年微生物群组成的变化，导致菊粉的糖解能力减弱，可能导致乙酸产生不足，这可能与从年轻到老年的过渡时期的健康问题有关。
