藜麦皂苷灌胃后大鼠尿液代谢及肠道菌变化

以藜麦皂苷为材料,对成年健康Sprague Dawley大鼠进行90 d经口暴露后结合肠道菌群及尿液代谢组学研究,探究其对肾脏的影响。实验分别将雌雄大鼠（n=48）分为高剂量（500 mg/kg）皂苷灌胃组、中剂量（50 mg/kg）皂苷灌胃组、低剂量（5 mg/kg）皂苷灌胃组与空白对照组,经口灌胃处理后,对肠道内容物进行16S rDNA分析,对尿液代谢物采用UPLC-MS分析,探究皂苷对大鼠的肠道菌群及代谢组学的影响。在雌雄大鼠中高剂量组大鼠肾脏切片均发生部分炎性变化。代谢组学结果显示,中低剂量组与空白对照组相比无明显差异,高剂量组大鼠在藜麦皂苷灌胃后,雌性大鼠尿液中发现差异代谢物101种,雄性大鼠尿液中发现差异代谢物29种,影响了维生素B6代谢、氨循环、色氨酸代谢等代谢过程。肠道菌群分析显示,藜麦皂苷灌胃组与对照组大鼠肠道菌群多样性差异明显。综上所述,藜麦皂苷在低剂量下无明显的毒性反应,然而在不可接触的中高剂量下有潜在的肾毒性。     

Functional Roles of B‐Vitamins in the Gut and Gut Microbiome

The gut microbiota produce hundreds of bioactive compounds, including B‐vitamins, which play significant physiological roles in hosts by supporting the fitness of symbiotic species and suppressing the growth of competitive species. B‐vitamins are also essential to the host and certain gut bacterium. Although dietary B‐vitamins are mainly absorbed from the small intestine, excess B‐vitamins unable to be absorbed in the small intestine are supplied to the distal gut. In addition, B‐vitamins are supplied from biosynthesis by distal gut microbiota. B‐vitamins in the distal colon may perform many important functions in the body. They act as 1) nutrients for a host and their microbiota, 2) regulators of immune cell activity, 3) mediators of drug efficacy, 4) supporters of survival, or the fitness of certain bacterium, 5) suppressors of colonization by pathogenic bacteria, and 6) modulators of colitis. Insights into basic biophysical principles, including the bioavailability of B‐vitamins and their derivatives in the distal gut are still not fully elucidated. Here, the function of single B‐vitamin in the distal gut including their roles in relation to bacteria are briefly reviewed. The prospect of extending analytical methods to better understand the role of B‐vitamins in the gut is also explored.     

婴儿肠道菌群中乳酸菌的分离鉴定及其多样性分析

结合传统培养方法与基于PacBio Sequel平台的单分子实时(Single-molecule real-time,SMRT)三代测序技术,对中国婴儿肠道菌群中的乳酸菌进行分离鉴定并分析其多样性,同时探究抗生素治疗对婴儿肠道乳酸菌多样性的影响。采用稀释涂布法培养分离粪便样品菌落,运用生理生化试验及16S rDNA序列比对鉴定菌株,并分析不同菌株间的系统发育关系。同时提取整体粪便样品的基因组DNA进行16S rDNA全长SMRT测序,利用QIIME、Mothur等生物信息学分析软件进行细菌群落结构和多样性分析。结果表明:中国婴儿肠道菌群中乳酸菌丰度及多样性普遍较低,传统培养方法分离出7种共32株乳酸菌,经鉴定为Lactobacillus rhamnosus、Enterococcus faecalis、L. gasseri、L. plantarum、L. casei、Pediococcus pentosaceus与Bifidobacterium longum;SMRT测序技术共获得11种乳酸菌,分别为L. rhamnosus、E. faecalis、L. gasseri、L. casei、P. pentosaceus、L. paracasei、L. salivarius、L. paraplantarum、L. porcinae、B. pseudocatenulatum、B. longum。其中,抗生素组仅分离检测到2种乳酸菌,分别为L. porcinae和E. faecalis。传统培养方法与SMRT测序技术对婴儿肠道菌群中乳酸菌多样性的分析存在差异,且抗生素的使用会降低婴儿肠道菌群中乳酸菌的多样性。     

纳米二氧化钛对小鼠亚慢性暴露的肠道微生物组和代谢组关联分析

基于微生物组学和代谢组学技术探讨纳米二氧化钛(TiO₂)颗粒对C57BL/6小鼠肠道微生物和粪便代谢物的影响及组学间的关联性。设置对照组和实验组,对照组灌胃磷酸盐缓冲液,实验组以100 mg/(kg m_b·d)纳米TiO₂灌胃,连续暴露13周。测定血糖、血脂等指标,并利用16S rDNA测序和气相色谱-质谱技术对肠道内容物进行分析,筛选出显著变化的微生物和差异代谢物。结果表明,与对照组相比,实验组小鼠空腹血糖水平显著上升(P=0.032)。厚壁菌门(Firmicutes)、样棒菌属(Allobaculum)、乳杆菌属(Lactobacillus)、颤螺旋菌属(Oscillospira)相对丰度增加。差异代谢物与甘油酯类代谢、半乳糖代谢、色氨酸代谢通路有关。厚壁菌门细菌相对丰度与差异代谢物水平呈负相关,其他门类的细菌相对丰度与差异代谢物水平呈正相关。推断小鼠在纳米TiO₂亚慢性暴露后,所产生的毒性作用可能与粪便中糖脂代谢异常相关。     

From Gut to Hormones: Unraveling the Role of Gut Microbiota in (Phyto)Estrogen Modulation in Health and Disease

The human gut microbiota regulates estrogen metabolism through the “estrobolome,” the collection of bacterial genes that encode enzymes like β-glucuronidases and β-glucosidases. These enzymes deconjugate and reactivate estrogen, influencing circulating levels. The estrobolome mediates the enterohepatic circulation and bioavailability of estrogen. Alterations in gut microbiota composition and estrobolome function have been associated with estrogen-related diseases like breast cancer, enometrial cancer, and polycystic ovarian syndrome (PCOS). This is likely due to dysregulated estrogen signaling partly contributed by the microbial impacts on estrogen metabolism. Dietary phytoestrogens also undergo bacterial metabolism into active metabolites like equol, which binds estrogen receptors and exhibits higher estrogenic potency than its precursor daidzein. However, the ability to produce equol varies across populations, depending on the presence of specific gut microbes. Characterizing the estrobolome and equol-producing genes across populations can provide microbiome-based biomarkers. Further research is needed to investigate specific components of the estrobolome, phytoestrogen-microbiota interactions, and mechanisms linking dysbiosis to estrogen-related pathology. However, current evidence suggests that the gut microbiota is an integral regulator of estrogen status with clinical relevance to women's health and hormonal disorders.     

Using a Metabotype Framework to Deliver Personalized Nutrition Improves Dietary Quality and Metabolic Health Parameters: A 12-Week Randomized Controlled Trial

Scope

Effective strategies for tailoring dietary advice to individuals are urgently needed. The effectiveness of personalized nutrition advice delivered using a metabotype framework in improving dietary quality and metabolic health biomarkers compared to population-level advice is investigated.

Materials and results

A 12-week parallel randomized controlled trial is performed with 107 healthy adults. Individuals in the personalized group are classified into metabotypes using four markers (triacylglycerol, high-density lipoprotein [HDL]-cholesterol, total cholesterol [TC], and glucose) and received dietary advice from decision tree algorithms containing metabotypes characteristics and individual traits. Individuals in the control group received generic dietary advice based on national guidelines. The personalized approach results in higher dietary quality assessed by the Alternate Mediterranean Diet Score (effect size [95% confidence interval, CI], 0.77 [0.07, 1.48], 12% versus 3% increase) and significantly lower concentrations of triacylglycerol (−0.17 [−0.28, −0.06] log10 mmol L⁻¹), TC (−0.42 [−0.74, −0.10] mmol L⁻¹), low-density lipoprotein (LDL)-cholesterol (−0.34, [−0.60, −0.09] mmol L⁻¹), and lower triacylglycerol-glucose index (−0.40, [−0.67, −0.13]). Sixteen phosphatidylcholines and six lysophosphatidylcholines, predominately with chain lengths of 30–36 carbons, are lower in the personalized group.

Conclusions

Personalized nutrition advice delivered using the metabotype framework is effective to improve dietary quality, which could result in reduced CVD risk, and metabolic heath biomarkers.     

Short-Term Ingestion of Essential Amino Acid Based Nutritional Supplements or Whey Protein Improves the Physical Function of Older Adults Independently of Gut Microbiome

Scope : Dietary proteins and essential amino acids (EAAs) are the major nutritional supplements that support the growth and activity of gut microbes contributing to the wellbeing of their host. This study hypothesizes that daily supplementation of the diet with either EAAs or whey protein for 12 weeks would improve the gut microbiome of older adults. Methods and results : The stool samples are processed and subjected to Illumina-based 16S ribosomal ribonucleic acid (rRNA) gene amplicon sequencing. In both groups, the most abundant families are found in order of relative abundance included: Bacteroidaceae, Lachnospiraceae, Ruminococcaceae, Prevotellaceae, Rikenellaceae, Enterobacteriaceae, Oscillospiraceae, Tannerellaceae, and Akkermansiaceae, which indicate that these subjects are able to maintain a same healthy microbial diversity in their guts. A significant finding is a reduction of proinflammatory cytokine, interleukin-18 (IL-18) in the EAAs group. It also uses the standard 6-min walking test (6MWT) as a measure of cardiopulmonary fitness. At the end of the study, the subjects in the EAAs group perform significantly better in the 6MWT as compared to the whey group. Conclusion : It seems plausible that the improved physical performance and reduced proinflammatory cytokine, IL-18 seen in the EAAs group, are independent of changes in gut microbiota.     

Personalized Cardio‐Metabolic Responses to an Anti‐Inflammatory Nutrition Intervention in Obese Adolescents: A Randomized Controlled Crossover Trial

1 Scope

Chronic inflammation and hypoadiponectinemia are characteristics of obesity‐induced insulin resistance (IR). The effect of an anti‐inflammatory nutrition supplement (AINS) on IR and adiponectin biology in overweight adolescents was investigated. The secondary objective was to examine the extent to which individuals’ biomarker profiles, derived from baseline phenotypes, predicted response or not to the AINS. Additionally, the impact of DNA methylation on intervention efficacy was assessed.

2 Methods and results

Seventy overweight adolescents (13–18 years) were recruited to this randomized controlled crossover trial. Participants received an AINS (long chain n‐3 PUFA, vitamin C, α‐tocopherol, green tea extract, and lycopene) and placebo for 8 weeks each. Homeostatic model assessment (HOMA)‐IR, adiponectin, inflammatory profiles, and DNA methylation were assessed. HOMA‐IR was unchanged in the total cohort. High‐molecular‐weight (HMW) adiponectin was maintained following the AINS while it decreased over time following the placebo intervention. HOMA‐IR decreased in 40% of subjects (responders) following the AINS. Responders’ pretreatment phenotype was characterized by higher HOMA‐IR, total and LDL cholesterol, but similar BMI in comparison to nonresponders. HMW adiponectin response to the AINS was associated with bidirectional modulation of adipogenic gene methylation.

3 Conclusion

The AINS modulated adiponectin biology, an early predictor of type 2 diabetes risk, was associated with bidirectional modulation of adipogenic gene methylation in weight‐stable overweight adolescents. HOMA‐IR decreased in a sub‐cohort of adolescents with an adverse metabolic phenotype. Thus, suggesting that more stratified or personalized nutrition approaches may enhance efficacy of dietary interventions.     

汉族和藏族婴儿肠道微生物群落结构和多样性分析

为了解民族因素对婴儿的影响,对中国汉族和藏族母乳喂养的健康婴儿粪便微生物菌群进行研究。通过16S rRNA高通量测序技术,发现两组粪便微生物的组成存在差异。在门水平上,汉族婴儿的放线菌门相对丰度较高,而藏族则以厚壁菌门为主,且两组间的厚壁菌门差异显著（P＜0.05）。基于UniFrac的非加权和加权的主坐标分析表明汉族和藏族婴儿肠道微生物群结构有显著性差异。此外,偏最小二乘判别分析显示两组间微生物明显分离。研究表明,肠道微生物群可以在不同民族的婴儿之间进行区别,从而扩展人类及其共生肠道微生物群共同进化的认识。     

食物多酚对肠道糖吸收与代谢的影响

多酚类物质,包括白藜芦醇、绿原酸、儿茶素等广泛存在于多种食物中,其普遍具有抗氧化、清除体内自由基等生物活性,对心血管疾病、肿瘤、癌症、糖尿病等疾病有一定的预防作用。越来越多的证据表明,食物多酚能在多个层面上影响糖代谢,如调节餐后血糖、刺激肠道激素分泌、提高胰岛素敏感性等。本文结合国内外研究结果,从肠道消化酶、肠道葡萄糖转运、微生物菌群生态及肠道激素分泌四个方面,讨论了食物多酚对肠道糖吸收与代谢的影响,以期为后期研究提供理论依据。     

Nutrition recommendations and science: next parallel steps

This article examines nutrition recommendations in relation to developments in nutrition science. Combining data on the genome, metabolome and microbiota is likely to open possibilities for personalized nutrition planning, but we are still far from practical applications. However, even these new steps are unlikely to challenge the role and importance of population‐based nutrition recommendations as a tool to promote dietary patterns, policies and public health. Developments in science could help in deriving more benefits from nutrition recommendations. For instance, improved accuracy of dietary intake assessment is needed both for surveillance and for understanding the quantitative interplay between diet and health. Applying metabolomics together with food diaries or questionnaires, and also modern technologies such as digital photography, are potentially interesting methods in this respect. Research on consumer behaviour, attitudes and policy interventions, such as taxation of unhealthy foods and nutrition labelling, are needed to gain more insight into how to change eating behaviour for better health at the population level. © 2015 Society of Chemical Industry     

配制酒个性化设计及设计实例

如何使配制酒产品体现出个性化,是每个配制酒设计人员必须思考的问题。阐明了何为配制酒个性化设计及设计原则、设计依据标准、设计差异性、具体设计方式等,并列举实例对配制酒个性化设计进行研究。     

老年住院患者营养状况的评价与分析

目的：用不同营养评价方法评价老年住院患者的营养状况,分析不同因素对老年住院患者营养状况的影响。方法：以2012年4月_2012年8月在中日友好医院住院治疗的年龄I〉65岁的225例老年患者为研究对象,入院后第三天使用微型营养评价精法（MNA—SF）对研究对象进行评估。进行评估时测量上臂围（AC）、小腿围（CC）、身高、体重、计算体质指数（BMI）,记录入院后距进行评估最近的一次血清白蛋白（ALB）检测值。使用统一问卷对研究对象进行调查。结果：MNA—SF、AC、CC、ALB评定住院老年患者营养不良和营养不良风险发生率分别是58．7％、24％、34．7％、22．7％,BMI的评定表明,低体重占20％,超重和肥胖占38．2％。年龄、对自身营养状况的关注度和日常生活活动能力显著影响老年住院患者的营养状况。结论：老年住院患者营养不良和营养不良风险发生率较高。加强营养宣教,增强生活自理能力、定期进行营养评价、积极进行营养干预和营养治疗有助于改善老年住院患者的营养状况。