scholarly journals Characterizing the Composition of the Pediatric Gut Microbiome: A Systematic Review

Nutrients ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 16 ◽  
Author(s):  
Kane E. Deering ◽  
Amanda Devine ◽  
Therese A. O’Sullivan ◽  
Johnny Lo ◽  
Mary C. Boyce ◽  
...  

The consortium of trillions of microorganisms that live inside the human gut are integral to health. Little has been done to collate and characterize the microbiome of children. A systematic review was undertaken to address this gap (PROSPERO ID: CRD42018109599). MEDLINE and EMBASE were searched using the keywords: “healthy preadolescent children” and “gut microbiome” to 31 August 2018. Of the 815 journal articles, 42 met the inclusion criteria. The primary outcome was the relative abundance of bacteria at the phylum, family, and genus taxonomic ranks. α-diversity, short chain fatty acid concentrations, diet, 16S rRNA sequencing region, and geographical location were documented. The preadolescent gut microbiome is dominated at the phylum level by Firmicutes (weighted overall average relative abundance = 51.1%) and Bacteroidetes (36.0%); genus level by Bacteroides (16.0%), Prevotella (8.69%), Faecalibacterium (7.51%), and Bifidobacterium (5.47%). Geographic location and 16S rRNA sequencing region were independently associated with microbial proportions. There was limited consensus between studies that reported α-diversity and short chain fatty acids. Broadly speaking, participants from non-Western locations, who were less likely to follow a Westernized dietary pattern, had higher α-diversity and SCFA concentrations. Confirmatory studies will increase the understanding of the composition and functional capacity of the preadolescent gut microbiome.

2021 ◽  
Author(s):  
Liying Zhang ◽  
Jiaqi Zhu ◽  
Qiutao Ding ◽  
Yanqi Huang ◽  
Hongbo Zhang ◽  
...  

Abstract The association between the gut microbiome and the five stages of colorectal cancer (CRC) (healthy, polyposis, nonadvanced adenoma, advanced adenoma, and cancer) remains unclear. We performed 16S rRNA sequencing of the V3-V4 amplicon from 999 samples from subjects at various stages of CRC development and constructed an accurate predictive random forest model for CRC development. In the testing set, our five-category CRC prediction classifier had accuracies of 0.84 and 0.74 using the relative operational taxonomic unit (OTU) abundances and relative genus abundances, respectively. Specifically, the OTU-based classifier had a sensitivity of 0.97 and specificity of 0.97 for CRC samples, and the genus-based classifier had a sensitivity of 0.97 and specificity of 0.95 for CRC samples. Meanwhile, the gut microbiota was found to differ at all stages of CRC development. The differential abundances of closely related bacteria were used to accurately classify the five stages of CRC development. Additionally, both unannotated and annotated OTUs played important roles in classifier modelling. Our work not only provides valuable 16S rRNA sequencing data from patients and healthy individuals on a large scale but also identifies reproducible gut microbiome biomarkers for CRC staging and highlights their potential applications as noninvasive microbiome biomarkers for diagnosis and as predictive CRC screening tests.


2018 ◽  
Vol 5 (1) ◽  
Author(s):  
Ashok Kumar Dubey ◽  
Niyati Uppadhyaya ◽  
Pravin Nilawe ◽  
Neeraj Chauhan ◽  
Santosh Kumar ◽  
...  

2020 ◽  
Author(s):  
Bo Cui ◽  
Huimin Chi ◽  
Wa Cao ◽  
Donghong Su ◽  
Honglian Yang ◽  
...  

Abstract Background: Environmental noise exposure and genetic risk factors are thought to be associated with gut microbiome that exacerbates Alzheimer’s disease (AD) pathology. However, the role and mechanism of environmental risk factors in early-onset AD (EOAD) pathogenesis remain unclear. Methods: We established APP/PS1 Tg and C57BL/6 (wild type [WT]) mouse models to evaluate the molecular pathways underlying EOAD pathophysiology following environmental noise exposure. 16S rRNA sequencing analyses were used for intestinal flora measurements and Tax4Fun were used to predict the metagenome content from 16S rRNA sequencing results; and assessment of the flora dysbiosis-triggered dyshomeostasis of oxi-inflamm-barrier and the effects of the CNS end of the gut–brain axis were conducted to explore the underlying pathological mechanisms. Results: Both WT and APP/PS1 mice showed statistically significant relationship between environmental noise and the taxonomic composition of the corresponding gut microbiome. Bacterial-encoded functional categories in noise-exposed WT and APP/PS1 mice included phospholipid and galactose metabolism, oxidative stress, and cell senescence. These alterations corresponded with imbalanced intestinal oxidation and anti-oxidation systems and low-grade systemic inflammation after noise exposure. Mechanistically, axis-series experiments demonstrated that after noise exposure, intestinal and hippocampal tight junction proteins levels reduced, whereas serum levels of inflammatory mediator were elevated. With regard to APP/PS1 overexpression, noise-induced abnormalities in the gut–brain axis may contribute to aggravation of neuropathology in the presymptomatic stage of EOAD mice model. Conclusions: Our results demonstrate that noise exposure has deleterious effects on the homeostasis of oxi-inflamm-barrier in the microbiome–gut–brain axis. Therefore, at least in a genetic context, chronic noise may aggravate the progression of EOAD.


2020 ◽  
Vol 10 (3) ◽  
pp. 204589402092914
Author(s):  
Takayuki J. Sanada ◽  
Koji Hosomi ◽  
Hiroki Shoji ◽  
Jonguk Park ◽  
Akira Naito ◽  
...  

The pathogenesis of pulmonary arterial hypertension is closely associated with dysregulated inflammation. Recently, abnormal alterations in gut microbiome composition and function were reported in a pulmonary arterial hypertension experimental animal model. However, it remains unclear whether these alterations are a result or the cause of pulmonary arterial hypertension. The purpose of this study was to investigate whether alterations in the gut microbiome affected the hemodynamics in SU5416/hypoxia rats. We used the SU5416/hypoxia rat model in our study. SU5416/hypoxia rats were treated with a single SU5416 injection (30 mg/kg) and a three-week hypoxia exposure (10% O2). Three SU5416/hypoxia rats were treated with a combination of four antibiotics (SU5416/hypoxia + ABx group) for four weeks. Another group was exposed to hypoxia (10% O2) without the SU5416 treatment, and control rats received no treatment. Fecal samples were collected from each animal, and the gut microbiota composition was analyzed by 16S rRNA sequencing. The antibiotic treatment significantly suppressed the vascular remodeling, right ventricular hypertrophy, and increase in the right ventricular systolic pressure in SU5416/hypoxia rats. 16S rRNA sequencing analysis revealed gut microbiota modification in SU5416/hypoxia + ABx group. The Firmicutes-to-Bacteroidetes ratio in SU5416/hypoxia rats was significantly higher than that in control and hypoxia rats. Compared with the control microbiota, 14 bacterial genera, including Bacteroides and Akkermansia, increased, whereas seven bacteria, including Rothia and Prevotellaceae, decreased in abundance in SU5416/hypoxia rats. Antibiotic-induced modification of the gut microbiota suppresses the development of pulmonary arterial hypertension. Dysbiosis may play a causal role in the development and progression of pulmonary arterial hypertension.


Animals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 118
Author(s):  
Zhengwen Wang ◽  
Xiongxiong Li ◽  
Lingyun Zhang ◽  
Jianping Wu ◽  
Shengguo Zhao ◽  
...  

The objective of this experiment was to evaluate the effect of different EOC (0.1425% cobalt lactate + 1.13% oregano essential oil + 98.7275% carrier) levels on in vitro rumen fermentation and microbial changes. Six EOC levels (treatments: 0 mg·L−1, CON; 50 mg·L−1, EOC1; 100 mg·L−1, EOC2; 400 mg·L−1, EOC3; 800 mg·L−1, EOC4 and 1500 mg·L−1, EOC5) were selected to be used to in vitro incubation. The in vitro dry matter digestibility (IVDMD), in vitro neutral detergent fiber digestibility (IVNDFD), in vitro acid detergent fiber digestibility (IVNDFD), pH, ammonia-nitrogen (NH3-N) concentration, total volatile fatty acid (TVFA) concentration and microbial protein (MCP) concentration were measured after 48 h incubation, after which the groups with significant nutrient digestibility and fermentation parameters were subjected to 16S rRNA sequencing. The results showed that the total gas production (GP) of the EOC5 group was higher than that of the other groups after 12 h of in vitro incubation. TVFA, NH3-N and MCP concentrations were also shown to be higher in group EOC5 than those in other groups (p < 0.05), while NH3-N and MCP concentrations in the EOC2 group were lower than those in other groups significantly (p < 0.05). The molar ratio of acetic acid decreased while the molar ratio of propionic acid increased after the addition of EOC. 16S rRNA sequencing revealed that the rumen microbiota was altered in response to adding EOC, especially for the EOC5 treatment, with firmicutes shown to be the most abundant (43.1%). The relative abundance of Rikenellaceae_RC9_gut_group was significantly lower, while the relative abundance of uncultured_bacterium_f_Muribaculaceae and Succiniclasticum was significantly higher in the EOC5 group than those in other groups (p < 0.05). Comprehensive analysis showed that EOC (1500 mg·L−1) could significantly increase gas production, alter sheep rumen fermentation parameters and microbiota composition.


Nutrients ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 2431 ◽  
Author(s):  
Jiayu Gu ◽  
Bingyong Mao ◽  
Shumao Cui ◽  
Xuemei Liu ◽  
Hao Zhang ◽  
...  

Fructooligosaccharides (FOS) are considered prebiotics and have been proven to selectively promote the growth of Bifidobacterium in the gut. This study aimed to clarify the effects of FOS intake on the composition of luminal and mucosal microbiota in mice. Briefly, mice were fed a 0% or 25% FOS (w/w)-supplemented diet for four weeks, and the composition of luminal and mucosal microbiota, especially the Bifidobacterium, was analyzed by sequencing the V3–V4 region of 16S rRNA and groEL gene, respectively. After FOS intervention, there were significant increases in the total and wall weights of the cecum and the amount of total short-chain fatty acids (SCFAs) in the cecal contents of the mice. At the phylum level, the results showed a significant increase in the relative abundance of Actinobacteria in the contents and mucosa from the cecum to the distal colon in the FOS group. Besides Bifidobacterium, a significant increase was observed in the relative abundance of Coprococcus in all samples at the genus level, which may be partially related to the increase in butyric acid levels in the luminal contents. Furthermore, groEL sequencing revealed that Bifidobacterium pseudolongum was almost the sole bifidobacterial species in the luminal contents (>98%) and mucosa (>89%). These results indicated that FOS can selectively promote B. pseudolongum proliferation in the intestine, either in the lumen or the mucosa from the cecum to the distal colon. Further studies are required to reveal the competitive advantage of B. pseudolongum over other FOS-metabolizing bacteria and the response mechanisms of B. pseudolongum to FOS.


Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 807
Author(s):  
Ning Chin ◽  
Gema Méndez-Lagares ◽  
Diana H. Taft ◽  
Victoria Laleau ◽  
Hung Kieu ◽  
...  

Breastfeeding is the gold standard for feeding infants because of its long-term benefits to health and development, but most infants in the United States are not exclusively breastfed in the first six months. We enrolled 24 infants who were either exclusively breastfed or supplemented with formula by the age of one month. We collected diet information, stool samples for evaluation of microbiotas by 16S rRNA sequencing, and blood samples for assessment of immune development by flow cytometry from birth to 6 months of age. We further typed the Bifidobacterium strains in stool samples whose 16S rRNA sequencing showed the presence of Bifidobacteriaceae. Supplementation with formula during breastfeeding transiently changed the composition of the gut microbiome, but the impact dissipated by six months of age. For example, Bifidobacterium longum, a bacterial species highly correlated with human milk consumption, was found to be significantly different only at 1 month of age but not at later time points. No immunologic differences were found to be associated with supplementation, including the development of T-cell subsets, B cells, or monocytes. These data suggest that early formula supplementation, given in addition to breast milk, has minimal lasting impact on the gut microbiome or immunity.


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