The Impact of Traumatic Brain Injury on Microbiome Composition: A Systematic Review

Traumatic brain injuries (TBIs) are a significant health problem, impacting millions of people every year. Although emerging evidence suggests that the composition of the gut microbiome is altered after TBI, no systematic review has been published on this topic. The objective of the present systematic review is to analyze publications that evaluate the impact of TBI on gut microbiome composition. Research articles were pulled from seven databases. The systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. In order for publications to be eligible for this review, they had to (1) report on original human- or animal-subjects research, (2) evaluate the impact of TBI on the microbiome, and (3) be written in English and (4) be published in a peer-reviewed journal. Of the seven articles that met these criteria, one involved human participants, while the other six reported on experimental animal studies. All studies found changes in the gut microbiome following TBI, with similar changes in bacterial populations observed across studies. The limitations of these studies included the use of primarily male animals, limitations of 16 S rRNA gene sequencing, and small sample sizes. This review was also limited by the small pool of studies conducted in this area. In summary, changes in bacterial populations of the gut microbiome, specifically increases in proteobacteria and firmicutes, were observed across the studies. By evaluating the changes in the microbiome resulting from TBI, potential therapeutic interventions could be explored.

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Consumption of Lysozyme-Rich Milk Can Alter Microbial Fecal Populations

Applied and Environmental Microbiology ◽

10.1128/aem.00956-12 ◽

2012 ◽

Vol 78 (17) ◽

pp. 6153-6160 ◽

Cited By ~ 56

Author(s):

Elizabeth A. Maga ◽

Prerak T. Desai ◽

Bart C. Weimer ◽

Nguyet Dao ◽

Dietmar Kültz ◽

...

Keyword(s):

Human Milk ◽

Gut Microbiome ◽

16S Rrna Gene Sequencing ◽

Fecal Microbiota ◽

Rrna Gene ◽

Gut Health ◽

Content Type ◽

Microbiome Composition ◽

The Impact ◽

Over Time

ABSTRACTHuman milk contains antimicrobial factors such as lysozyme and lactoferrin that are thought to contribute to the development of an intestinal microbiota beneficial to host health. However, these factors are lacking in the milk of dairy animals. Here we report the establishment of an animal model to allow the dissection of the role of milk components in gut microbiota modulation and subsequent changes in overall and intestinal health. Using milk from transgenic goats expressing human lysozyme at 68%, the level found in human milk and young pigs as feeding subjects, the fecal microbiota was analyzed over time using 16S rRNA gene sequencing and the G2 Phylochip. The two methods yielded similar results, with the G2 Phylochip giving more comprehensive information by detecting more OTUs. Total community populations remained similar within the feeding groups, and community member diversity was changed significantly upon consumption of lysozyme milk. Levels ofFirmicutes(Clostridia) declined whereas those ofBacteroidetesincreased over time in response to the consumption of lysozyme-rich milk. The proportions of these major phyla were significantly different (P< 0.05) from the proportions seen with control-fed animals after 14 days of feeding. Within phyla, the abundance of bacteria associated with gut health (BifidobacteriaceaeandLactobacillaceae) increased and the abundance of those associated with disease (Mycobacteriaceae,Streptococcaceae,Campylobacterales) decreased with consumption of lysozyme milk. This study demonstrated that a single component of the diet with bioactivity changed the gut microbiome composition. Additionally, this model enabled the direct examination of the impact of lysozyme on beneficial microbe enrichment versus detrimental microbe reduction in the gut microbiome community.

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Viscoelastometric Testing to Assess Hemostasis of COVID-19: A Systematic Review

Journal of Clinical Medicine ◽

10.3390/jcm10081740 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1740

Author(s):

Marion Bareille ◽

Michaël Hardy ◽

Jonathan Douxfils ◽

Stéphanie Roullet ◽

Dominique Lasne ◽

...

Keyword(s):

Systematic Review ◽

Mechanical Strength ◽

Small Sample ◽

The Common ◽

Small Sample Sizes ◽

Definition Of ◽

Reported Data ◽

Prophylactic Anticoagulation ◽

The Impact ◽

Heparin Neutralization

Infection by SARS-CoV-2 is associated with a high risk of thrombosis. The laboratory documentation of hypercoagulability and impaired fibrinolysis remains a challenge. Our aim was to assess the potential usefulness of viscoelastometric testing (VET) to predict thrombotic events in COVID-19 patients according to the literature. We also (i) analyzed the impact of anticoagulation and the methods used to neutralize heparin, (ii) analyzed whether maximal clot mechanical strength brings more information than Clauss fibrinogen, and (iii) critically scrutinized the diagnosis of hypofibrinolysis. We performed a systematic search in PubMed and Scopus databases until December 31st, 2020. VET methods and parameters, and patients’ features and outcomes were extracted. VET was performed for 1063 patients (893 intensive care unit (ICU) and 170 non-ICU, 44 studies). There was extensive heterogeneity concerning study design, VET device used (ROTEM, TEG, Quantra and ClotPro) and reagents (with non-systematic use of heparin neutralization), timing of assay, and definition of hypercoagulable state. Notably, only 4 out of 25 studies using ROTEM reported data with heparinase (HEPTEM). The common findings were increased clot mechanical strength mainly due to excessive fibrinogen component and impaired to absent fibrinolysis, more conspicuous in the presence of an added plasminogen activator. Only 4 studies out of the 16 that addressed the point found an association of VETs with thrombotic events. So-called functional fibrinogen assessed by VETs showed a variable correlation with Clauss fibrinogen. Abnormal VET pattern, often evidenced despite standard prophylactic anticoagulation, tended to normalize after increased dosing. VET studies reported heterogeneity, and small sample sizes do not support an association between the poorly defined prothrombotic phenotype of COVID-19 and thrombotic events.

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Relationship between Prenatal or Postnatal Exposure to Pesticides and Obesity: A Systematic Review

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18137170 ◽

2021 ◽

Vol 18 (13) ◽

pp. 7170

Author(s):

Helena Pinos ◽

Beatriz Carrillo ◽

Ana Merchán ◽

Judit Biosca-Brull ◽

Cristian Pérez-Fernández ◽

...

Keyword(s):

Systematic Review ◽

Body Weight ◽

Weight Control ◽

Animal Studies ◽

Pesticide Exposure ◽

Endocrine Disrupting Chemicals ◽

Overweight And Obesity ◽

Postnatal Exposure ◽

Body Weight Control ◽

The Impact

In recent years, the worldwide prevalence of overweight and obesity among adults and children has dramatically increased. The conventional model regarding the onset of obesity is based on an imbalance between energy intake and expenditure. However, other possible environmental factors involved, such as the exposure to chemicals like pesticides, cannot be discarded. These compounds could act as endocrine-disrupting chemicals (EDC) that may interfere with hormone activity related to several mechanisms involved in body weight control. The main objective of this study was to systematically review the data provided in the scientific literature for a possible association between prenatal and postnatal exposure to pesticides and obesity in offspring. A total of 25 human and 9 animal studies were analyzed. The prenatal, perinatal, and postnatal exposure to organophosphate, organochlorine, pyrethroid, neonicotinoid, and carbamate, as well as a combined pesticide exposure was reviewed. This systematic review reveals that the effects of pesticide exposure on body weight are mostly inconclusive, finding conflicting results in both humans and experimental animals. The outcomes reviewed are dependent on many factors, including dosage and route of administration, species, sex, and treatment duration. More research is needed to effectively evaluate the impact of the combined effects of different pesticides on human health.

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Endoscopic pituitary surgery: a systematic review and meta-analysis

Journal of Neurosurgery ◽

10.3171/2007.12.17635 ◽

2009 ◽

Vol 111 (3) ◽

pp. 545-554 ◽

Cited By ~ 189

Author(s):

Abtin Tabaee ◽

Vijay K. Anand ◽

Yolanda Barrón ◽

David H. Hiltzik ◽

Seth M. Brown ◽

...

Keyword(s):

Systematic Review ◽

Meta Analysis ◽

Pituitary Surgery ◽

Small Sample ◽

Csf Leak ◽

Tumor Control ◽

Published Data ◽

Complication Rates ◽

Short Term ◽

The Impact

Object Surgery on the pituitary gland is increasingly being performed through an endoscopic approach. However, there is little published data on its safety and relative advantages over traditional microscope-based approaches. Published reports are limited by small sample size and nonrandomized study design. A meta-analysis allows for a description of the impact of endoscopic surgery on short-term outcomes. Methods The authors performed retrospective review of data from their institution as well as a systematic review of the literature. The pooled data were analyzed for descriptive statistics on short-term outcomes. Results Nine studies (821 patients) met inclusion criteria. Overall, the pooled rate of gross tumor removal was 78% (95% CI 67–89%). Hormone resolution was achieved in 81% (95% CI 71–91%) of adrenocorticotropic hormone secreting tumors, 84% (95% CI 76–92%) of growth hormone secreting tumors, and 82% (95% CI 70–94%) of prolactin secreting tumors. The pooled complication rates were 2% (95% CI 0–4%) for CSF leak and 1% (95% CI 0–2%) for permanent diabetes insipidus. There were 2 deaths reported in the literature that were both related to vascular injury, giving an overall mortality rate of 0.24%. Conclusions The results of this meta-analysis support the safety and short-term efficacy of endoscopic pituitary surgery. Future studies with long-term follow-up are required to determine tumor control.

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Gut microbiome signatures of risk and prodromal markers of Parkinson’s disease

10.1101/2019.12.11.872481 ◽

2019 ◽

Author(s):

Sebastian Heinzel ◽

Velma T. E. Aho ◽

Ulrike Suenkel ◽

Anna-Katharina von Thaler ◽

Claudia Schulte ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Gut Microbiome ◽

Physical Inactivity ◽

Disease Onset ◽

Rem Sleep Behavior Disorder ◽

Sleep Behavior ◽

Microbiome Composition ◽

Β Diversity ◽

The Impact

AbstractObjectivesAlterations of the gut microbiome in Parkinson’s disease (PD) have been repeatedly demonstrated. However, little is known about whether such alterations precede disease onset and how they may be related to risk and prodromal markers of PD. We investigated associations of these features with gut microbiome composition.MethodsEstablished risk and prodromal markers of PD as well as factors related to diet/lifestyle, bowel function and medication were studied in relation to bacterial α-/β-diversity, enterotypes, and taxonomic composition in stool samples of 666 elderly TREND study participants.ResultsAmong risk and prodromal markers, physical inactivity, constipation and age showed associations with α- and β-diversity, and for both measures subthreshold parkinsonism and physical inactivity showed interaction effects. Moreover, male sex, possible REM-sleep behavior disorder (RBD), smoking as well as body-mass-index, antidiabetic and urate-lowering medication were associated with β-diversity. Physical inactivity and constipation severity were increased in individuals with the Firmicutes-enriched enterotype. Subthreshold parkinsonism was least frequently observed in individuals with the Prevotella-enriched enterotype. Differentially abundant taxa were linked to constipation, physical inactivity, possible RBD, and subthreshold parkinsonism. Substantia nigra hyperechogenicity, olfactory loss, depression, orthostatic hypotension, urinary/erectile dysfunction, PD family history and the overall prodromal PD probability showed no significant microbiome associations.InterpretationSeveral risk and prodromal markers of PD are associated with changes in gut microbiome composition. However, the impact of the gut microbiome on PD risk and potential microbiome-dependent subtypes in the prodrome of PD need further investigation based on prospective clinical and (multi)omics data in incident PD cases.

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Metabolic phenotyping for understanding the gut microbiome and host metabolic interplay

Emerging Topics in Life Sciences ◽

10.1042/etls20170079 ◽

2017 ◽

Vol 1 (4) ◽

pp. 325-332 ◽

Cited By ~ 2

Author(s):

Abigail R. Basson ◽

Anisha Wijeyesekera

Keyword(s):

Gut Microbiome ◽

Skin Diseases ◽

Compositional Analysis ◽

Exciting Field ◽

Inflammatory Skin Diseases ◽

Metabolic Phenotyping ◽

Microbiome Composition ◽

Host Health ◽

The Impact ◽

Analytical Approaches

There is growing interest in the role of the gut microbiome in human health and disease. This unique complex ecosystem has been implicated in many health conditions, including intestinal disorders, inflammatory skin diseases and metabolic syndrome. However, there is still much to learn regarding its capacity to affect host health. Many gut microbiome research studies focus on compositional analysis to better understand the causal relationships between microbial communities and disease phenotypes. Yet, microbial diversity and complexity is such that community structure alone does not provide full understanding of microbial function. Metabolic phenotyping is an exciting field in systems biology that provides information on metabolic outputs taking place in the system at a given moment in time. These readouts provide information relating to by-products of endogenous metabolic pathways, exogenous signals arising from diet, drugs and other lifestyle and environmental stimuli, as well as products of microbe–host co-metabolism. Thus, better understanding of the gut microbiome and host metabolic interplay can be gleaned using such analytical approaches. In this review, we describe research findings focussed on gut microbiota–host interactions, for functional insights into the impact of microbiome composition on host health. We evaluate different analytical approaches for capturing metabolic activity and discuss analytical methodological advancements that have made a contribution to the field. This information will aid in developing novel approaches to improve host health in the future, and therapeutic modulation of the microbiome may soon augment conventional clinical strategies.

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Abstract 18: Gut Microbiome Modifies the Protective Effects of a Mediterranean Dietary Pattern Against Diabetes Mellitus in US Hispanics/ Latinos: The Hispanic Community Health Study/ Study of Latinos (HCHS/SOL)

Circulation ◽

10.1161/circ.141.suppl_1.18 ◽

2020 ◽

Vol 141 (Suppl_1) ◽

Cited By ~ 1

Author(s):

Dong Wang ◽

Qibin Qi ◽

Zheng Wang ◽

Mykhaylo Usyk ◽

Daniela Sotres-Alvarez ◽

...

Keyword(s):

Diabetes Mellitus ◽

Relative Abundance ◽

Gut Microbiome ◽

16S Rrna Gene Sequencing ◽

Health Study ◽

Rrna Gene ◽

Inverse Association ◽

Protective Effects ◽

Acid Fermentation ◽

Microbiome Composition

Introduction: Little is known about whether the effect of a healthy diet on diabetes mellitus (DM) is modified by the gut microbiome in human. Hypothesis: We hypothesize that the gut microbiome modifies the inverse association between the Mediterranean diet (MedDiet) and risk of DM. Methods: This study included 543 DM cases, 805 with impaired glucose tolerance (IGT) and 394 with normal glucose regulation (NGR) in adults 23-83yrs old from the HCHS/SOL. Fecal samples were profiled using 16s rRNA gene sequencing. We applied QIIME 2 to cluster sequences into OTUs and assign taxonomies, and PICRUSt to predict metagenomic gene functions. Adherence to the MedDiet was evaluated by a MedDiet index using the average of two 24-hr dietary recalls. We applied MaAsLin2 to quantify associations between the MedDiet index and microbial features with adjustment for confounding factors listed in the caption of Fig. 1. Results: MedDiet was associated with phylogenetically diverse, rare, and abundant gut microbes (Fig. 1a). For example, a higher MedDiet index was associated with a higher relative abundance of Faecalibacterium Prausnitzii [FDR-adjusted p (q) =0.002], but a lower relative abundance of Collinsella aerofaciens ( q =0.009). We found that several microbial functions related to plant-derived polysaccharide degradation such as fructuronate reductase ( q =0.02), and short-chain fatty acid fermentation such as butyryl-CoA dehydrogenase ( q =0.002) were enriched in participants with higher MedDiet index. We found that the inverse association between MedDiet and risk of DM was more pronounced in participants with greater abundance of Prevotella copri , but weaker in participants whose gut microbial communities were dominated by Bacteroides ( P interaction =0.02 for IGT/DM vs NGR, Fig. 1b). Conclusions: Adherence to the MedDiet is associated with diverse gut microorganisms and microbial functions. The inverse association between MedDiet and risk of DM might be modified by gut microbiome composition. 1

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Changes in the Intestinal Microbiome during a Multispecies Probiotic Intervention in Compensated Cirrhosis

Nutrients ◽

10.3390/nu12061874 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1874 ◽

Cited By ~ 1

Author(s):

Angela Horvath ◽

Marija Durdevic ◽

Bettina Leber ◽

Katharina di Vora ◽

Florian Rainer ◽

...

Keyword(s):

Gut Microbiome ◽

Controlled Trial ◽

16S Rrna Gene Sequencing ◽

Intestinal Microbiome ◽

Rrna Gene ◽

Microbiome Composition ◽

Beneficial Effects ◽

Compensated Cirrhosis ◽

Gut Barrier Function ◽

Probiotic Treatment

Probiotics have been used in trials to therapeutically modulate the gut microbiome and have shown beneficial effects in cirrhosis. However, their effect on the microbiome of cirrhosis patients is not fully understood yet. Here, we tested the effects of a multispecies probiotic on microbiome composition in compensated cirrhosis. The gut microbiome composition of 58 patients with compensated cirrhosis from a randomized controlled trial who received a daily dose of multispecies probiotics or placebo for six months was analysed by 16S rRNA gene sequencing. Microbiome composition of patients who received probiotics was enriched with probiotic strains and the abundance of Faecalibacterium prausnitzii, Syntrophococcus sucromutans, Bacteroides vulgatus, Alistipes shahii and a Prevotella species was increased in the probiotic group compared to the placebo group. Patients who had microbiome changes in response to probiotic treatment also showed a significant increase in neopterin and a significant decrease in faecal zonulin levels after intervention, which was not observed in placebo-treated patients or patients with unchanged microbiome compositions. In conclusion, multispecies probiotics may enrich the microbiome of compensated cirrhotic patients with probiotic bacteria during a six-month intervention and beneficially change the residential microbiome and gut barrier function.

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The Impact of Primer Design on Amplicon-Based Metagenomic Profiling Accuracy: Detailed Insights into Bifidobacterial Community Structure

Microorganisms ◽

10.3390/microorganisms8010131 ◽

2020 ◽

Vol 8 (1) ◽

pp. 131 ◽

Cited By ~ 6

Author(s):

Leonardo Mancabelli ◽

Christian Milani ◽

Gabriele Andrea Lugli ◽

Federico Fontana ◽

Francesca Turroni ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

In Silico ◽

In Silico Analysis ◽

Amplification Efficiency ◽

Rrna Gene ◽

Test Case ◽

Bacterial Populations ◽

Taxonomic Marker ◽

The Impact

Next Generation Sequencing (NGS) technologies have overcome the limitations of cultivation-dependent approaches and allowed detailed study of bacterial populations that inhabit the human body. The consortium of bacteria residing in the human intestinal tract, also known as the gut microbiota, impacts several physiological processes important for preservation of the health status of the host. The most widespread microbiota profiling method is based on amplification and sequencing of a variable portion of the 16S rRNA gene as a universal taxonomic marker among members of the Bacteria domain. Despite its popularity and obvious advantages, this 16S rRNA gene-based approach comes with some important limitations. In particular, the choice of the primer pair for amplification plays a major role in defining the accuracy of the reconstructed bacterial profiles. In the current study, we performed an in silico PCR using all currently described 16S rRNA gene-targeting primer pairs (PP) in order to assess their efficiency. Our results show that V3, V4, V5, and V6 were the optimal regions on which to design 16S rRNA metagenomic primers. In detail, PP39 (Probio_Uni/Probio_Rev), PP41 (341F/534R), and PP72 (970F/1050R) were the most suitable primer pairs with an amplification efficiency of >98.5%. Furthermore, the Bifidobacterium genus was examined as a test case for accurate evaluation of intra-genus performances at subspecies level. Intriguingly, the in silico analysis revealed that primer pair PP55 (527f/1406r) was unable to amplify the targeted region of any member of this bacterial genus, while several other primer pairs seem to rather inefficiently amplify the target region of the main bifidobacterial taxa. These results highlight that selection of a 16S rRNA gene-based PP should be done with utmost care in order to avoid biases in microbiota profiling results.

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The Effects of Glucosamine and Chondroitin Sulfate on Gut Microbial Composition: A Systematic Review of Evidence from Animal and Human Studies

Nutrients ◽

10.3390/nu11020294 ◽

2019 ◽

Vol 11 (2) ◽

pp. 294 ◽

Cited By ~ 8

Author(s):

Anna Shmagel ◽

Ryan Demmer ◽

Daniel Knights ◽

Mary Butler ◽

Lisa Langsetmo ◽

...

Keyword(s):

Systematic Review ◽

Gut Microbiota ◽

Chondroitin Sulfate ◽

Gut Microbiome ◽

Human Studies ◽

Journal Articles ◽

Microbial Composition ◽

Microbiome Composition ◽

Search Terms ◽

Quality Evidence

Oral glucosamine sulfate (GS) and chondroitin sulfate (CS), while widely marketed as joint-protective supplements, have limited intestinal absorption and are predominantly utilized by gut microbiota. Hence the effects of these supplements on the gut microbiome are of great interest, and may clarify their mode of action, or explain heterogeneity in therapeutic responses. We conducted a systematic review of animal and human studies reporting the effects of GS or CS on gut microbial composition. We searched MEDLINE, EMBASE, and Scopus databases for journal articles in English from database inception until July 2018, using search terms microbiome, microflora, intestinal microbiota/flora, gut microbiota/flora and glucosamine or chondroitin. Eight original articles reported the effects of GS or CS on microbiome composition in adult humans (four articles) or animals (four articles). Studies varied significantly in design, supplementation protocols, and microbiome assessment methods. There was moderate-quality evidence for an association between CS exposure and increased abundance of genus Bacteroides in the murine and human gut, and low-quality evidence for an association between CS exposure and an increase in Desulfovibrio piger species, an increase in Bacteroidales S24-7 family, and a decrease in Lactobacillus. We discuss the possible metabolic implications of these changes for the host. For GS, evidence of effects on gut microbiome was limited to one low-quality study. This review highlights the importance of considering the potential influence of oral CS supplements on gut microbiota when evaluating their effects and safety for the host.

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