紫苏叶促进大鼠肠胃消化吸收作用的研究

研究紫苏叶促进肠蠕动与健胃消食的作用。实验分成两大组（A组,B组）。A组SD大鼠68只,随机分8组：阴性对照组、阳性对照组（1．4g／kg）、紫苏叶石油醚提取物低剂量组（15g／kg）、中剂量组（30g／kg）、高剂量组（60g／kg）,乙醇提取物低剂量组（10g／kg）、中剂量组（20g／kg）、高剂量组（30g／kg）。连续给药10d,测大鼠小肠碳末推进百分率。B组SD大鼠56只,随机分7组：阴性对照组、紫苏叶石油醚提取物及乙醇提取物大、中、小剂量组。连续给药8d,测大鼠胃部总酸度和总酸排出量。结果表明：与阴性对照组相比,各剂量组大鼠小肠碳末推进百分率与总酸排出量均增高（P〈0．05,P〈0．01）。紫苏叶的石油醚提取物及乙醇提取物具有促进肠胃消化吸收的作用。     

The Gut Microbiota,Tumorigenesis, and Liver Diseases

In recent decades, diseases concerning the gut microbiota have presented some of the most serious public health problems worldwide. The human host’s physiological status is influenced by the intestinal microbiome, thus integrating external factors, such as diet, with genetic and immune signals. The notion that chronic inflammation drives carcinogenesis has been widely established for various tissues. It is surprising that the role of the microbiota in tumorigenesis has only recently been recognized, given that the presence of bacteria at tumor sites was first described more than a century ago. Extensive epidemiological studies have revealed that there is a strong link between the gut microbiota and some common cancers. However, the exact molecular mechanisms linking the gut microbiota and cancer are not yet fully understood. Changes to the gut microbiota are instrumental in determining the occurrence and progression of hepatocarcinoma, chronic liver diseases related to alcohol, nonalcoholic fatty liver disease (NAFLD), and cirrhosis. To be specific, the gut milieu may play an important role in systemic inflammation, endotoxemia, and vasodilation, which leads to complications such as spontaneous bacterial peritonitis and hepatic encephalopathy. Relevant animal studies involving gut microbiota manipulations, combined with observational studies on patients with NAFLD, have provided ample evidence pointing to the contribution of dysbiosis to the pathogenesis of NAFLD. Given the poor prognosis of these clinical events, their prevention and early management are essential. Studies of the composition and function of the gut microbiota could shed some light on understanding the prognosis because the microbiota serves as an essential component of the gut milieu that can impact the aforementioned clinical events. As far as disease management is concerned, probiotics may provide a novel direction for therapeutics for hepatocellular carcinoma (HCC) and NAFLD, given that probiotics function as a type of medicine that can improve human health by regulating the immune system. Here, we provide an overview of the relationships among the gut microbiota, tumors, and liver diseases. In addition, considering the significance of bacterial homeostasis, we discuss probiotics in this article in order to guide treatments for related diseases.     

Self-nanoemulsifying drug delivery system of docosahexanoic acid: development,in vitro,in vivo characterization

Context: Docosahexanoic acid (DHA) is an essential omega-3 fatty acid for normal brain development and its use has increased considerably in recent years.

Objective: The aim of this study is to develop and evaluate self-nanoemulsifying drug delivery systems (SNEDDS) of DHA for improved palatability, dispersibility and bioavailability.

Methods: The SNEDDS were prepared and evaluated for miscibility, employing different combinations of olive oil and soyabean oil as oil phase, Span 80, Span 20, soya phosphatidylcholine, Labrafil M 1944 CS as surfactants while Tween 80, PEG 400, Cremophor RH40 and propylene glycol as cosurfactants. Thermodynamically stable SNEDDS were characterized for dispersibility, self-emulsification time, droplet size, zeta potential along with sensory analysis. The optimized formulation was subjected to ex vivo and in vivo evaluation such as intestinal permeability, memory performance test, brain concentration and histopathology studies.

Results: The optimized SNEDDS formulation showed emulsification time of 27?±?4.7?s with droplet size of 17.6?±?3.5?nm and zeta potential of??37.6?±?0.5?mV. Intestinal absorption study depicted 18.3%, 21.5%, 41.5%, 98.7% absorption of DHA with SNEDDS-based formulation in comparison to 8.2%, 15.1%, 28.8%, 46.1% absorption of DHA with oil-based marketed formulation after 0.5, 1, 2 and 4?h. DHA concentration in brain homogenate was found to be increased to 2.6-fold in comparison to DHA-marketed formulation. This could be ascribed to enhanced dispersibility and bioavailability of DHA from nanosized formulation.

Conclusion: The developed formulation led to enhanced dispersibility and bioavailability of DHA due to the formation of nanodroplets.     

养殖河鱼屯肠道细菌16S rDNA多样性分析

从养殖河鱼屯肠道内容物中提取细菌基因组DNA,通过PCR和TA克隆构建了细菌的16SrDNA基因文库研究肠道内容物细菌的多样性。结果表明,大部分序列通过NCBI数据库的BLAST搜索发现相似率为88%~99%,共有8个OTUs的序列相似率小于98%;鉴定出4类系统发育菌群,分别是变形菌门γ亚群(Gamma-Proteobacteria,44.8%)、CFB菌群细菌(Cytophaga-Flexibacter-Bacteroides,6.9%),厚壁菌门(Firmicutes,13.8%)、Unclassified group(34.5%),其中变形菌门γ亚群为肠道内容物中的优势细菌类群。文库多样性分析结果显示养殖河鱼屯肠道内容物中有着丰富的细菌多样性群落。     

巯基化党参多糖对鼠李糖乳杆菌肠道黏附定植作用的影响

益生菌的肠道黏附是其实现长期肠道定植的关键因素。为增加外源性益生菌的肠道黏附性,对前期分离所得党参多糖(CPP-2)采用羧甲基化和巯基化两步化学修饰法,制备巯基化党参多糖(sC-CPP-2)。通过体外黏附实验和激光共聚焦显微镜法分析在添加sC-CPP-2情况下肠黏液对鼠李糖乳杆菌(LGG)的黏附效果,利用党参多糖及其修饰组分与海藻酸钠形成的复合薄膜,间接验证sC-CPP-2对LGG的黏附性,并利用流变仪和经典拉伸实验检测sC-CPP-2与肠道黏液之间的相互作用关系。结果表明：羧甲基党参多糖(C-CPP-2)的取代度为0.588±0.026,sC-CPP-2中巯基含量为(279.50±5.97)μmol/g, C-CPP-2经巯基化修饰后处于巯基和羧基共存状态。sC-CPP-2表面巯基可与LGG表面蛋白质上的半胱氨酸残基形成二硫键,增加LGG的肠道黏附性。sC-CPP-2与肠黏液的最大分离力为(101.82±5.78) mN,黏附总功为(120.07±6.81)μJ,二者间相互作用力增强,表观黏度变大,黏合力显著增强。sC-CPP-2能够起到连接LGG与肠黏液的中介作用,增强LGG的肠道...     

Psychological Stress Exacerbates Inflammation of the Ileum via the Corticotropin-Releasing Hormone-Mast Cell Axis in a Mouse Model of Eosinophilic Enteritis

The effects of psychological stress on eosinophilic gastrointestinal disorders have not been elucidated. This study investigated the effects of psychological stress in a mouse model of eosinophilic enteritis (EoN). BALB/c mice were treated with ovalbumin (OVA) to create an EoN model and subjected to either water avoidance stress (WAS) or sham stress (SS). Microscopic inflammation, eosinophil and mast cell counts, mRNA expression, and protein levels of type 2 helper T cell (Th2) cytokines in the ileum were compared between groups. We evaluated ex vivo intestinal permeability using an Ussing chamber. A corticotropin-releasing hormone type 1 receptor (CRH-R1) antagonist was administered before WAS, and its effects were analyzed. WAS significantly increased diarrhea occurrence and, eosinophil and mast cell counts, and decreased the villus/crypt ratio compared to those in the SS group. The mRNA expression of CRH, interleukin IL-4, IL-5, IL-13, eotaxin-1, and mast cell tryptase β2 significantly increased, and the protein levels of IL-5, IL-13, and OVA-specific immunoglobulin E (IgE) also significantly increased in the WAS group. Moreover, WAS significantly increased the intestinal permeability. The CRH-R1 antagonist significantly inhibited all changes induced by WAS. Psychological stress exacerbated ileal inflammation via the CRH-mast cell axis in an EoN mouse model.     

通过RRLC-Q-TOF MS和UPLC-QQQ MS分析原人参三醇型皂苷在人肠道菌群中的代谢产物

通过高分离度快速液相色谱-四极杆飞行时间质谱(RRLC-Q-TOF MS)和超高效液相色谱-三重四极杆质谱(UPLC-QQQ MS)法对原人参三醇型皂苷Re、Rg 1、Rg 2、Rh 1、Rf、F 1、R 1在人肠道菌群中的转化产物进行定性、定量分析,确定原人参三醇型皂苷的代谢产物、转化途径和60 h时的转化率。结果表明,人参皂苷Re的转化产物为人参皂苷Rg 1、Rg 2、Rh 1、F 1和PPT,转化率为91%;人参皂苷Rg 1的转化产物为人参皂苷Rh 1、F 1和PPT,转化率为80%;人参皂苷Rg 2的转化产物为人参皂苷Rh 1和PPT,转化率为73%;人参皂苷Rh 1和F 1主要通过PPT代谢,转化率分别为82%和81%;人参皂苷Rf的转化产物为人参皂苷Rh 1和PPT,转化率为89%;三七皂苷R 1的转化产物为人参皂苷Rg 1、R 2、Rh 1和PPT,转化率为79%。原人参三醇型皂苷类成分可被人肠道菌群代谢,主要通过丢失糖残基形成转化产物,而次级皂苷和苷元是人参在体内发挥药理作用的物质基础。     

Metformin Influence on the Intestinal Microbiota and Organism of Rats with Metabolic Syndrome

Metformin is a first-line drug for DM2 treatment and prevention, but its complex effect on impaired glucose tolerance (IGT), including its influence on myocardial resistance to ischemia-reperfusion injury, is not completely studied. We aimed to evaluate the influence of metformin on the intestinal microbiota (IM), metabolism, and functional and morphological characteristics of myocardium in rats with IGT. IGT was modelled in SPF Wistar rats with a high-fat diet and streptozotocin and nicotinamide injection. Rats were divided into three groups: IGT (without treatment), IGT MET (metformin therapy), and CRL (without IGT induction and treatment). IGT group was characterized by: higher body weight, increased serum glucose and total cholesterol levels, atherogenic coefficient, impairment in the functional parameters of the isolated heart during perfusion, and larger myocardium infarction (MI) size in comparison with the CRL group. IM of IGT rats differed from that of CRL: an increase of Bacteroides, Acinetobacter, Akkermansia, Roseburia, and a decrease of Lactobacillus genera representation. Metformin therapy led to the diminishing of metabolic syndrome (MS) symptoms, which correlated with IM restoration, especially with the growth of Akkermansia spp. and decline of Roseburia populations and their influence on other members of IM. The obtained results allow us to consider from a new point of view the expediency of probiotic A. muciniphila use for MS treatment.     

Drugs,Guts, Brains,but Not Rock and Roll: The Need to Consider the Role of Gut Microbiota in Contemporary Mental Health and Wellness of Emerging Adults

Emerging adulthood (ages 18–25) is a critical period for neurobiological development and the maturation of the hypothalamic–pituitary–adrenal axis. Recent findings also suggest that a natural perturbation of the gut microbiota (GM), combined with other factors, may create a unique vulnerability during this period of life. The GM of emerging adults is thought to be simpler, less diverse, and more unstable than either younger or older people. We postulate that this plasticity in the GM suggests a role in the rising mental health issues seen in westernized societies today via the gut–brain–microbiota axis. Studies have paid particular attention to the diversity of the microbiota, the specific function and abundance of bacteria, and the production of metabolites. In this narrative review, we focus specifically on diet, physical activity/exercise, substance use, and sleep in the context of the emerging adult. We propose that this is a crucial period for establishing a stable and more resilient microbiome for optimal health into adulthood. Recommendations will be made about future research into possible behavioral adjustments that may be beneficial to endorse during this critical period to reduce the probability of a “dysbiotic” GM and the emergence and severity of mental health concerns.     

Intratracheal Transplantation of Mesenchymal Stem Cells Attenuates Hyperoxia-Induced Microbial Dysbiosis in the Lungs,Brain, and Gut in Newborn Rats

We attempted to determine whether intratracheal (IT) transplantation of mesenchymal stem cells (MSCs) could simultaneously attenuate hyperoxia-induced lung injuries and microbial dysbiosis of the lungs, brain, and gut in newborn rats. Newborn rats were exposed to hyperoxia (90% oxygen) for 14 days. Human umbilical cord blood-derived MSCs (5 × 10⁵) were transplanted via the IT route on postnatal day (P) five. At P14, the lungs were harvested for histological, biochemical, and microbiome analyses. Bacterial 16S ribosomal RNA genes from the lungs, brain, and large intestine were amplified, pyrosequenced, and analyzed. IT transplantation of MSCs simultaneously attenuated hyperoxia-induced lung inflammation and the ensuing injuries, as well as the dysbiosis of the lungs, brain, and gut. In correlation analyses, lung interleukin-6 (IL-6) levels were significantly positively correlated with the abundance of Proteobacteria in the lungs, brain, and gut, and it was significantly inversely correlated with the abundance of Firmicutes in the gut and lungs and that of Bacteroidetes in the lungs. In conclusion, microbial dysbiosis in the lungs, brain, and gut does not cause but is caused by hyperoxic lung inflammation and ensuing injuries, and IT transplantation of MSCs attenuates dysbiosis in the lungs, brain, and gut, primarily by their anti-oxidative and anti-inflammatory effects.