Gut Microbiota Prevents Sugar Alcohol-Induced Diarrhea

While poorly-absorbed sugar alcohols such as sorbitol are widely used as sweeteners, they may induce diarrhea in some individuals. However, the factors which determine an individual’s susceptibility to sugar alcohol-induced diarrhea remain unknown. Here, we show that specific gut bacteria are involved in the suppression of sorbitol-induced diarrhea. Based on 16S rDNA analysis, the abundance of Enterobacteriaceae bacteria increased in response to sorbitol consumption. We found that Escherichia coli of the family Enterobacteriaceae degraded sorbitol and suppressed sorbitol-induced diarrhea. Finally, we showed that the metabolism of sorbitol by the E. coli sugar phosphotransferase system helped suppress sorbitol-induced diarrhea. Therefore, gut microbiota prevented sugar alcohol-induced diarrhea by degrading sorbitol in the gut. The identification of the gut bacteria which respond to and degrade sugar alcohols in the intestine has implications for microbiome science, processed food science, and public health.     

Gut Microbiota Profile and Its Association with Clinical Variables and Dietary Intake in Overweight/Obese and Lean Subjects: A Cross-Sectional Study

We aimed to differentiate gut microbiota composition of overweight/obese and lean subjects and to determine its association with clinical variables and dietary intake. A cross-sectional study was performed with 96 overweight/obese subjects and 32 lean subjects. Anthropometric parameters were positively associated with Collinsella aerofaciens, Dorea formicigenerans and Dorea longicatena, which had higher abundance the overweight/obese subjects. Moreover, different genera of Lachnospiraceae were negatively associated with body fat, LDL and total cholesterol. Saturated fatty acids (SFAs) were negatively associated with the genus Intestinimonas, a biomarker of the overweight/obese group, whereas SFAs were positively associated with Roseburia, a biomarker for the lean group. In conclusion, Dorea formicigenerans, Dorea longicatena and Collinsella aerofaciens could be considered obesity biomarkers, Lachnospiraceae is associated with lipid cardiovascular risk factors. SFAs exhibited opposite association profiles with butyrate-producing bacteria depending on the BMI. Thus, the relationship between diet and microbiota opens new tools for the management of obesity.     

Foxtail Millet Improves Blood Glucose Metabolism in Diabetic Rats through PI3K/AKT and NF-κB Signaling Pathways Mediated by Gut Microbiota

Foxtail millet (FM) is receiving ongoing increased attention due to its beneficial health effects, including the hypoglycemic effect. However, the underlying mechanisms of the hypoglycemic effect have been underexplored. In the present study, the hypoglycemic effect of FM supplementation was confirmed again in high-fat diet and streptozotocin-induced diabetic rats with significantly decreased fasting glucose (FG), glycated serum protein, and areas under the glucose tolerance test (p < 0.05). We employed 16S rRNA and liver RNA sequencing technologies to identify the target gut microbes and signaling pathways involved in the hypoglycemic effect of FM supplementation. The results showed that FM supplementation significantly increased the relative abundance of Lactobacillus and Ruminococcus_2, which were significantly negatively correlated with FG and 2-h glucose. FM supplementation significantly reversed the trends of gene expression in diabetic rats. Specifically, FM supplementation inhibited gluconeogenesis, stimulated glycolysis, and restored fatty acid synthesis through activation of the PI3K/AKT signaling pathway. FM also reduced inflammation through inhibition of the NF-κB signaling pathway. Spearman’s correlation analysis indicated a complicated set of interdependencies among the gut microbiota, signaling pathways, and metabolic parameters. Collectively, the above results suggest that the hypoglycemic effect of FM was at least partially mediated by the increased relative abundance of Lactobacillus, activation of the PI3K/AKT signaling pathway, and inhibition of the NF-κB signaling pathway.     

Habitual Dietary Intake Affects the Altered Pattern of Gut Microbiome by Acarbose in Patients with Type 2 Diabetes

The aim of this research was to reveal the characteristics of gut microbiome altered by acarbose intervention in Japanese patients with type 2 diabetes (T2D) and its possible association with habitual dietary intake. Eighteen patients with T2D were administered acarbose for four weeks. The abundances of two major phyla, namely Actinobacteria and Bacteroidetes, were reciprocally changed accompanied by the acarbose intervention. There were also significant changes in the abundances of ten genera, including the greater abundance of Bifidobacterium, Eubacterium, and Lactobacillus and the lower abundance of Bacteroides in the group after the intervention than that before the intervention. Hierarchical clustering of habitual dietary intake was performed based on the pattern of changes in the gut microbiota and were classified into distinct three clusters. Cluster I consisted of sucrose, cluster II mainly included fat intake, and cluster III mainly included carbohydrate intake. Moreover, the amount of change in Faecalibacterium was positively correlated with the intake of rice, but negatively correlated with the intake of bread. The intake of potato was negatively correlated with the amount of change in Akkermansia and Subdoligranulum. Acarbose altered the composition of gut microbiome in Japanese patients with T2D, which might be linked to the habitual dietary intake.     

基于高通量测序的鼠类肠道细菌群落多样性分析

目的探明鼠类肠道细菌群落组成和多样性。方法分离鼠类完整肠道并提取总DNA,利用Oxford Nanopore Technologies公司(MK1C)的纳米孔单分子测序技术对其肠道细菌16S rRNA的全区序列进行测序,统计肠道细菌的操作分类单元(operational taxonomic unit,OTU)数量,分析其物种组成、丰度及Alpha、Beta多样性。结果获得鼠类肠道细菌16S rRNA优质序列1161377条,根据序列相似性进行聚类分析获得1484个OTUs。共注释到24个门,48个纲,113个目,241个科和534个属;在门分类水平上,以厚壁菌门Firmicutes和变形菌门Proteobacteria为优势门类;在属分类水平上,优势属为肠球菌Enterococcus、乳酸杆菌Lactobacillus和葡萄球菌Staphylococcus,其丰度分别为38.7%,17.65%和7.48%。Alpha多样性分析结果显示,鼠类肠道细菌的观测物种数、Chao1指数、Shannon指数和Simpson指数分别为1484、1825.77、3.91和0.058。Beta多样性分析结果显示臭鼬和小家鼠肠道菌群组成最接近,而黄胸鼠和小家鼠肠道菌群组成相差最大。结论鼠类肠道细菌菌群整体多样性比较丰富,可为有效评估鼠传疾病传播风险提供依据。     

基于网络药理学和16SrDNA测序的当归六黄汤合煎与单煎治疗阴虚甲亢作用的差异研究

目的 探讨当归六黄汤的抗阴虚甲亢作用,阐释传统汤剂合煎和单煎的差异。方法 运用网络药理学方法,筛选当归六黄汤的主要活性成分和治疗阴虚甲亢疾病的相关靶点,并对交集靶点进行蛋白质-蛋白质相互作用（protein-protein interaction,PPI）网络分析、基因本体（gene ontology,GO）功能和京都基因与基因组百科全书（Kyoto encyclopedia of genes and genomes,KEGG）通路富集分析,构建药材-成分-靶点-通路网络;进一步进行实验验证,构建阴虚甲亢大鼠模型,评价当归六黄汤合煎和单煎对阴虚甲亢大鼠体质量、粪便含水率及相关血清学指标的影响;利用16S rDNA测序技术,揭示合煎和单煎对大鼠肠道微生物群落多样性的影响。结果 筛选获得当归六黄汤方中102个活性成分,检索出与阴虚甲亢有关靶点116个。富集分析获得871条GO条目和158条KEGG相关条目（P<0.05）,其中生物过程（biological process,BP）675条、细胞组分（cellular component,CC）77条、分子功能（molecular fu...     

Washed microbiota transplantation stopped the deterioration of amyotrophic lateral sclerosis: The first case report and narrative review

Amyotrophic lateral sclerosis (ALS) is known as a progressive paralysis disorder characterized by degeneration of upper and lower motor neurons, and has an average survival time of three to five years. Growing evidence has suggested a bidirectional link between gut microbiota and neurodegeneration. Here we aimed to report one female case with ALS, who benefited from washed microbiota transplantation (WMT), an improved fecal microbiota transplantation (FMT), through a transendoscopic enteral tube during a 12-month follow-up. Notedly, the accidental scalp trauma the patient suffered later was treated with prescribed antibiotics that caused ALS deterioration. The subsequent rescue WMTs successfully stopped the progression of the disease with a quick improvement. The plateaus and reversals occurred during the whole course of WMT. The stool and blood samples from the first WMT to the last were collected for dynamic microbial and metabolomic analysis. We observed the microbial and metabolomic changing trend consistent with the disease status. This case report for the first time shows the direct clinical evidence on using WMT for treating ALS, indicating that WMT may be the novel treatment strategy for controlling this so-called incurable disease.     

基于“人卧血归于肝”探讨睡眠障碍对代谢相关脂肪性肝病的影响

“人卧血归于肝”是睡眠与“肝”藏象功能的重要关联,也是肝主藏血、肝主疏泄的具体体现。现基于“人卧血归于肝” 梳理睡眠与“肝”藏象的必然联系,总结睡眠障碍对肝脏糖脂代谢紊乱的影响,指出睡眠障碍通过中枢调控系统引发进食异常从而增加肝脏代谢负担,并通过其诱发的免疫反应加重肝脏代谢紊乱和肝脏炎症,也可增加胰岛素抵抗引发糖脂代谢异常并增加肝脏脂肪堆积。除此以外,睡眠障碍还可通过影响肠道菌群的变化对脂肪的消化吸收促进肝脏脂肪变性。故以“人卧血归于肝”的理论引出睡眠对于肝脏疾病的重要作用,并以期为进一步探索中西医结合防治方案提供理论参考。     

胰腺炎基础研究进展与展望

近年来,胰腺炎的病理生理机制研究取得了诸多实质性进展。其中,急性胰腺炎领域热点内容众多,如胰蛋白酶原异常激活、病理性钙超载、线粒体功能障碍、自噬、内质网应激、NF-κb激活、细胞程序性死亡等。慢性胰腺炎领域的研究则更多集中于胰腺星状细胞激活对慢性胰腺炎纤维化的影响,以此为主干,又可进一步研究自噬、外泌体等与胰腺星状细胞活化的关系。在胰腺炎的基础研究中,可以进行机制的深入发掘,而机制的发掘又为寻找疾病分子标记物、新药研发、治疗靶点选择等提供了源源不断的新思路。此外,免疫、肠道微生态等作为当前基础研究的热点领域,其在胰腺炎发生、发展中的作用值得进一步探索。