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111.
The increased prevalence of type 2 diabetes mellitus (T2DM) and life expectancy of diabetic patients fosters the worldwide prevalence of retinopathy and nephropathy, two major microvascular complications that have been difficult to treat with contemporary glucose-lowering medications. The gut microbiota (GM) has become a lively field research in the last years; there is a growing recognition that altered intestinal microbiota composition and function can directly impact the phenomenon of ageing and age-related disorders. In fact, human GM, envisaged as a potential source of novel therapeutics, strongly modulates host immunity and metabolism. It is now clear that gut dysbiosis and their products (e.g. p-cresyl sulfate, trimethylamine?N?oxide) dictate a secretory associated senescence phenotype and chronic low-grade inflammation, features shared in the physiological process of ageing (“inflammaging”) as well as in T2DM (“metaflammation”) and in its microvascular complications. This review provides an in-depth look on the crosstalk between GM, host immunity and metabolism. Further, it characterizes human GM signatures of elderly and T2DM patients. Finally, a comprehensive scrutiny of recent molecular findings (e.g. epigenetic changes) underlying causal relationships between GM dysbiosis and diabetic retinopathy/nephropathy complications is pinpointed, with the ultimate goal to unravel potential pathophysiological mechanisms that may be explored, in a near future, as personalized disease-modifying therapeutic approaches. 相似文献
112.
Kundan Kumar Gaurao V. Dhoke Ashok K. Sharma Shubham K. Jaiswal Vineet K. Sharma 《Journal of cellular biochemistry》2019,120(7):11206-11215
The human gut harbors diverse bacterial species in the gut, which play an important role in the metabolism of food and host health. Recent studies have also revealed their role in altering the pharmacological properties and efficacy of oral drugs through promiscuous metabolism. However, the atomistic details of the enzyme-drug interactions of gut bacterial enzymes which can potentially carry out the metabolism of drug molecules are still scarce. A well-known example is the FDA drug amphetamine (a central nervous system stimulant), which has been predicted to undergo promiscuous metabolism by gut bacteria. Therefore, to understand the atomistic details and energy landscape of the gut microbial enzyme-mediated metabolism of this drug, molecular dynamics studies were performed. It was observed that amphetamine binds to tyramine oxidase from the Escherichia coli strain present in the human gut microbiota at the binding site harboring polar and nonpolar amino acids. The stability analysis of amphetamine at the binding site showed that the binding is stable and the free energy for the binding of amphetamine was found to be ~ −51.71 kJ/mol. The insights provided by this study on promiscuous metabolism of amphetamine by a gut enzyme will be very useful to improve the efficacy of the drug. 相似文献
113.
Bing Wei Yi Chen Tingyan Lu Wenjiao Cao Zhenhua Tang Haiou Yang 《Genetics and molecular biology》2022,45(2)
The process from high-risk human papillomavirus (HR-HPV) infection to cervical cancer is a continuous and long-term process, but the pathogenesis of the whole process is not completely clear. Here, 59 Chinese women were engaged in this study, and divided into five groups: normal healthy group, HR-HPV infections group, low-grade intraepithelial neoplasia (LSIL) group, high-SIL(HSIL) group, and cervical cancer group. With the occurrence of HR-HPV infection and the development of cervical lesions, the diversity of vaginal microbiota species was increased, and the relative abundance of Lactobacillus (L.), the dominant bacteria in maintaining vaginal microecological balance, was decreased gradually. In contrast, the abundance of Actinobacteria in the four disease groups was significantly higher than that in normal group. Furthermore L. iners may be related to the serious progression of cervical cancer. After analyzing the whole process, we found that Gardnerella(G.), Atopobium(A.) and Dialister(D.) have important effects on both persistent HR-HPV infection and the pathogenesis of cervical cancer. In addition, PICRUSt2 and KEGG results showed that the KEGG pathways enriched by the predicted genes of vaginal microbiota in cancer group included metabolic diseases, endocrine system and immune systems when compared with that in normal group. These findings may provide insights into the pathogenesis of cervical cancer, and help to improve the early detection and prevention of cervical precancerous lesions. 相似文献
114.
近年来得益于宏基因组学和代谢组学研究技术的进步,人类健康或疾病状态下,肠道菌群与宿主相关性研究剧增,但其潜在机制研究仍然处于初级阶段。以慢性肾脏病(chronic kidney disease, CKD)为研究背景,大量证据表明患者宿主和肠道菌群之间存在双向关联。一方面,CKD的病理状态下存在特殊的肠道菌群代谢模式;另一方面,肠道菌群紊乱及分解代谢后产生的肠源性尿毒症毒素(gut-derived uremic toxins, GDUT)也加速CKD进展。因此,本文着重探讨硫酸吲哚酚、硫酸对甲酚和氧化三甲胺等关键GDUT对CKD患者结肠转运时间、肾转运体和自清除作用的潜在作用机制。进而从微生态角度出发,提出优化膳食摄入、调节肠道菌群等肾保护性措施,为延缓CKD的进展提供新的治疗思路。 相似文献
115.
Sara Santarossa Alexandra R. Sitarik Christine Cole Johnson Jia Li Susan V. Lynch Dennis R. Ownby Alex Ramirez Germaine LM. Yong Andrea E. Cassidy-Bushrow 《Journal of Exercise Nutrition & Biochemistry》2021,25(4):24
[Purpose] To determine whether physical activity (PA), primarily the recommended 60 minutes of moderate-to-vigorous PA, is associated with gut bacterial microbiota in 10-year-old children.[Methods] The Block Physical Activity Screener, which provides minutes/day PA variables, was used to determine whether the child met the PA recommendations. 16S rRNA sequencing was performed on stool samples from the children to profile the composition of their gut bacterial microbiota. Differences in alpha diversity metrics (richness, Pielou’s evenness, and Faith’s phylogenetic diversity) by PA were determined using linear regression, whereas beta diversity (unweighted and weighted UniFrac) relationships were assessed using PERMANOVA. Taxon relative abundance differentials were determined using DESeq2.[Results] The analytic sample included 321 children with both PA and 16S rRNA sequencing data (mean age [SD] =10.2 [0.8] years; 54.2% male; 62.9% African American), where 189 (58.9%) met the PA recommendations. After adjusting for covariates, meeting the PA recommendations as well as minutes/day PA variables were not significantly associated with gut richness, evenness, or diversity (p ≥ 0.19). However, meeting the PA recommendations (weighted UniFrac R2 = 0.014, p = 0.001) was significantly associated with distinct gut bacterial composition. These compositional differences were partly characterized by increased abundance of Megamonas and Anaerovorax as well as specific Christensenellaceae_R-7_group taxa in children with higher PA.[Conclusion] Children who met the recommendations of PA had altered gut microbiota compositions. Whether this translates to a reduced risk of obesity or associated metabolic diseases is still unclear. 相似文献
116.
117.
目的 探讨去卵巢对小鼠肠道菌群和血脂的影响.方法 12只10周龄C57BL/6小鼠随机分为2组:假手术组(SHAM组)和去卵巢组(OVX组),每组6只,进行12周的喂养.每2周测定小鼠体质量,12周后测肝脏指数、血清三酰甘油水平和游离脂肪酸水平,小肠进行病理学检查,收集小鼠粪便并在Illumina MiSeq测序平台进... 相似文献
118.
Lepercq P Gérard P Béguet F Raibaud P Grill JP Relano P Cayuela C Juste C 《FEMS microbiology letters》2004,237(1):65-72
Several H2-producing fermentative anaerobic bacteria including Clostridium, Klebsiella and Fusobacteria degraded octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) (36 microM) to formaldehyde (HCHO) and nitrous oxide (N2O) with rates ranging from 5 to 190 nmol h(-1)g [dry weight] of cells(-1). Among these strains, C. bifermentans strain HAW-1 grew and transformed HMX rapidly with the detection of the two key intermediates the mononitroso product and methylenedinitramine. Its cellular extract alone did not seem to degrade HMX appreciably, but degraded much faster in the presence of H2, NADH or NADPH. The disappearance of HMX was concurrent with the release of nitrite without the formation of the nitroso derivative(s). Results suggest that two types of enzymes were involved in HMX metabolism: one for denitration and the second for reduction to the nitroso derivative(s). 相似文献
119.
The fecal and mucosal microbiota of infants with rectal bleeding and the fecal microbiota of healthy age-matched controls were investigated by fluorescent in situ hybridization. Bifidobacteria were the main genus in both the feces and mucosa. The other genera tested, Bacteroides, Clostridium, Escherichia coli and lactobacilli/enterococci, represented only minor constituents. No differences in fecal microbiota were observed between patients and controls. In the patients, however, four times greater numbers of bifidobacteria were observed in the feces when compared to the mucosa. Notwithstanding this difference, a strong positive correlation prevailed for bifidobacteria in feces and mucosal samples. The genera assessed accounted for 16% of total bacterial counts on mucosal samples and for 47% of total bacterial counts in feces. This indicates that the unidentified part of the microbiota, especially on the mucosa, deserves more attention. 相似文献
120.
Fecal microbial diversity in a strict vegetarian as determined by molecular analysis and cultivation
Fecal microbial diversity in a strictly vegetarian woman was determined by the 16S rDNA library method, terminal restriction fragment length polymorphism (T-RFLP) analysis and a culture-based method. The 16S rDNA library was generated from extracted fecal DNA, using bacteria-specific primers. Randomly selected clones were partially sequenced. T-RFLP analysis was performed using amplified 16S rDNA. The lengths of T-RF were analyzed after digestion by HhaI and MspI. The cultivated bacterial isolates were used for partial sequencing of 16S rDNA. Among 183 clones obtained, approximately 29% of the clones belonged to 13 known species. About 71% of the remaining clones were novel "phylotypes" (at least 98% similarity of clone sequence). A total of 55 species or phylotypes were identified among the 16S rDNA library, while the cultivated isolates included 22 species or phylotypes. In addition, many new phylotypes were detected from the 16S rDNA library. The 16S rDNA library and isolates commonly included the Bacteroides group, Bifidobacterium group, and Clostridium rRNA clusters IV, XIVa, XVI and XVIII. T-RFLP analysis revealed the major composition of the vegetarian gut microbiota were Clostridium rRNA subcluster XIVa and Clostridium rRNA cluster XVIII. The dominant feature of this strictly vegetarian gut microbiota was the detection of many Clostridium rRNA subcluster XIVa and C. ramosum (Clostridium rRNA cluster XVIII). 相似文献