Evaluation of the orally administered calcium alginate aerogel on the changes of gut microbiota and hepatic and renal function of Wistar rats

The present study evaluates the effect of calcium alginate aerogel as a potential drug carrier, on the liver and kidney functions, and on the gut microbiota of Wistar rats. The studied alginate aerogel was prepared in the form of nanoparticles using the jet cutting technique, and they were characterized in terms of specific surface areas, outer morphology and particle size distribution. For the in vivo study, calcium alginate aerogel was administered orally, and liver and kidney functions were tested for one week and for four weeks in two distinct studies. During the short-term in vivo study, feces samples were collected for bacterial DNA extraction followed by 16S rRNA gene sequencing analyses to detect changes in gut microbiota. Results showed that the prepared alginate aerogel has an average BET-specific surface area of around 540 m2/g, with a pore volume of 7.4 cc/g, and pore width of 30–50 nm. The in vivo study revealed that the levels of the studied kidney and liver enzymes didn’t exceed the highest level of the normal range. The study of gut microbiota showed different patterns; certain groups of bacteria, such as Clostridia and Bacteriodia, increased during the aerogels regime and continued to increase after the aerogel was stopped. While other groups such as Erysipelotrichia, and Candidatus saccharibacteria increased during aerogels treatment, and then decreased again after one month. Members of the Bacilli class showed a unique trend, that is, after being the most abundant group (63%) at time 0, their relative abundance decreased dramatically until it reached < 5%; which was the case even after stopping the aerogel treatment.

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Encapsulated cyclosporine does not change the composition of the human microbiota when assessed ex vivo and in vivo

Journal of Medical Microbiology ◽

10.1099/jmm.0.001130 ◽

2020 ◽

Vol 69 (6) ◽

pp. 854-863

Author(s):

Catherine O'Reilly ◽

Órla O’Sullivan ◽

Paul D. Cotter ◽

Paula M. O’Connor ◽

Fergus Shanahan ◽

...

Keyword(s):

Pilot Study ◽

Gut Microbiota ◽

Targeted Delivery ◽

Healthy Subjects ◽

Ex Vivo ◽

16S Rrna Gene Sequencing ◽

Rrna Gene ◽

Microbiota Composition ◽

Faecal Samples

Introduction. Management of steroid-refractory ulcerative colitis has predominantly involved treatment with systemic cyclosporine A (CyA) and infliximab. Aim. The purpose of this study was to assess the effect of using a colon-targeted delivery system CyA formulation on the composition and functionality of the gut microbiota. Methodology. Ex vivo faecal fermentations from six healthy control subjects were treated with coated minispheres (SmPill) with (+) or without (−) CyA and compared with a non-treated control in a model colon system. In addition, the in vivo effect of the SmPill+CyA formulation was investigated by analysing the gut microbiota in faecal samples collected before the administration of SmPill+CyA and after 7 consecutive days of administration from eight healthy subjects who participated in a pilot study. Results. Analysis of faecal samples by 16S rRNA gene sequencing indicated little variation in the diversity or relative abundance of the microbiota composition before or after treatment with SmPill minispheres with or without CyA ex vivo or with CyA in vivo. Short-chain fatty acid profiles were evaluated using gas chromatography, showing an increase in the concentration of n-butyrate (P=0.02) and acetate (P=0.32) in the faecal fermented samples incubated in the presence of SmPill minispheres with or without CyA. This indicated that increased acetate and butyrate production was attributed to a component of the coated minispheres rather than an effect of CyA on the microbiota. Butyrate and acetate levels also increased significantly (P=0.05 for both) in the faecal samples of healthy individuals following 7 days’ treatment with SmPill+CyA in the pilot study. Conclusion. SmPill minispheres with or without CyA at the clinically relevant doses tested here have negligible direct effects on the gut microbiota composition. Butyrate and acetate production increased, however, in the presence of the beads in an ex vivo model system as well as in vivo in healthy subjects. Importantly, this study also demonstrates the relevance and value of using ex vivo colon models to predict the in vivo impact of colon-targeted drugs directly on the gut microbiota.

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Monosodium Glutamate Induces Changes in Hepatic and Renal Metabolic Profiles and Gut Microbiome of Wistar Rats

Nutrients ◽

10.3390/nu13061865 ◽

2021 ◽

Vol 13 (6) ◽

pp. 1865

Author(s):

Kanokwan Nahok ◽

Jutarop Phetcharaburanin ◽

Jia V. Li ◽

Atit Silsirivanit ◽

Raynoo Thanan ◽

...

Keyword(s):

16S Rrna ◽

Gut Microbiota ◽

16S Rrna Gene ◽

Gut Microbiome ◽

Wistar Rats ◽

Monosodium Glutamate ◽

16S Rrna Gene Sequencing ◽

Rrna Gene ◽

Male Wistar Rats ◽

The Impact

The short- and long-term consumption of monosodium glutamate (MSG) increases urinary pH but the effects on the metabolic pathways in the liver, kidney and the gut microbiota remain unknown. To address this issue, we investigated adult male Wistar rats allocated to receive drinking water with or without 1 g% MSG for 2 weeks (n = 10, each). We performed a Nuclear Magnetic Resonance (NMR) spectroscopy-based metabolomic study of the jejunum, liver, and kidneys, while faecal samples were collected for bacterial DNA extraction to investigate the gut microbiota using 16S rRNA gene sequencing. We observed significant changes in the liver of MSG-treated rats compared to controls in the levels of glucose, pyridoxine, leucine, isoleucine, valine, alanine, kynurenate, and nicotinamide. Among kidney metabolites, the level of trimethylamine (TMA) was increased, and pyridoxine was decreased after MSG-treatment. Sequencing of the 16S rRNA gene revealed that MSG-treated rats had increased Firmicutes, the gut bacteria associated with TMA metabolism, along with decreased Bifidobacterium species. Our data support the impact of MSG consumption on liver and kidney metabolism. Based on the gut microbiome changes, we speculate that TMA and its metabolites such as trimethylamine-N-oxide (TMAO) may be mediators of the effects of MSG on the kidney health.

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Role of Modified Diet and Gut Microbiota in Metabolic Endotoxemia in Mice

10.21203/rs.3.rs-603542/v1 ◽

2021 ◽

Author(s):

Iram Liaqat ◽

Arjumand Iqbal Durrani ◽

Urooj Zafar ◽

Saima Rubab ◽

Mehwish Faheem ◽

...

Keyword(s):

Gut Microbiota ◽

16S Rrna Gene Sequencing ◽

Diet Group ◽

The Body ◽

Chow Diet ◽

Rrna Gene ◽

Group 2 ◽

Rrna Gene Sequencing ◽

Metabolic Endotoxemia

Abstract This study was aimed to investigate the effect of cultured gut microbiota (GM) from obese humans coupled HFD in inducing metabolic endotoxemia in humanized mice. In total, 30 strains were isolated from 10 stool samples of obese patients. Following morphological and biochemical characterization, 16S rRNA gene sequencing of six abundant isolates identified these as Klebsiella aerogenes, Levilactobacillus brevis, Escherichia coli, Staphylococcus aureus, Bacillus cereus and Bacillus subtilis (MZ052089- MZ052094). In vivo trial using above six isolates, known as human gut microbiota (HGM), was performed for six months. Sixteen mice were distributed into four groups i.e., G1 (control) mice fed with chow diet, group 2 (G2) mice with HFD, group 3 (G3) mice with HFD + HGM and group 4 (G4) mice with chow diet + HGM. Body mass index (BMI) and plasma endotoxins were measured pre and post experiment. In vivo study revealed that HFD + HGM caused significant increase (3.9 g/cm at 20 weeks) in the body weight and BMI (0.4g/cm post experiment) of G3 mice compared to the other groups. One way ANOVA showed significantly higher level of endotoxins (2.41, 4.08 and 3.7 mmol/l) in mice groups G2, G3 and G4, respectively, indicating onset of metabolic endotoxemia. Cecal contents of experimental mice groups showed more diversified microbiota in mice groups G1 and G4 compared to G2 and G3 where high fat feeding alone and combined with obese gut microbiota caused a shift in microbial diversity as observed by all five strains belonging to either Firmicutes or Bacteriodetes phyla, respectively. In conclusion, current study reported that minor alteration in GM composition through HFD feeding and cultured GM transfer has significant impact in development of metabolic endotoxemia, possibly via modified intestinal permeability.

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Fecal Methylmercury Correlates With Gut Microbiota Taxa in Pacific Walruses (Odobenus rosmarus divergens)

Frontiers in Microbiology ◽

10.3389/fmicb.2021.648685 ◽

2021 ◽

Vol 12 ◽

Author(s):

Sarah E. Rothenberg ◽

Danielle N. Sweitzer ◽

Bryna R. Rackerby ◽

Claire E. Couch ◽

Lesley A. Cohen ◽

...

Keyword(s):

Gut Microbiota ◽

Total Mercury ◽

Linear Models ◽

16S Rrna Gene Sequencing ◽

Systemic Circulation ◽

Rrna Gene ◽

Fecal Samples ◽

Odobenus Rosmarus Divergens ◽

Odobenus Rosmarus

ObjectivesMethylmercury metabolism was investigated in Pacific walruses (Odobenus rosmarus divergens) from St. Lawrence Island, Alaska, United States.MethodsTotal mercury and methylmercury concentrations were measured in fecal samples and paired colon samples (n = 16 walruses). Gut microbiota composition and diversity were determined using 16S rRNA gene sequencing. Associations between fecal and colon mercury and the 24 most prevalent gut microbiota taxa were investigated using linear models.ResultsIn fecal samples, the median values for total mercury, methylmercury, and %methylmercury (of total mercury) were 200 ng/g, 4.7 ng/g, and 2.5%, respectively, while in colon samples, the median values for the same parameters were 28 ng/g, 7.8 ng/g, and 26%, respectively. In fecal samples, methylmercury was negatively correlated with one Bacteroides genus, while members of the Oscillospirales order were positively correlated with both methylmercury and %methylmercury (of total mercury). In colon samples, %methylmercury (of total mercury) was negatively correlated with members of two genera, Romboutsia and Paeniclostridium.ConclusionsMedian %methylmercury (of total mercury) was 10 times higher in the colon compared to the fecal samples, suggesting that methylmercury was able to pass through the colon into systemic circulation. Fecal total mercury and/or methylmercury concentrations in walruses were comparable to some human studies despite differences in seafood consumption rates, suggesting that walruses excreted less mercury. There are no members (at this time) of the Oscillospirales order which are known to contain the genes to methylate mercury, suggesting the source of methylmercury in the gut was from diet and not in vivo methylation.

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An In Vitro Pilot Fermentation Study on the Impact of Chlorella pyrenoidosa on Gut Microbiome Composition and Metabolites in Healthy and Coeliac Subjects

Molecules ◽

10.3390/molecules26082330 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2330

Author(s):

Carmen van der Linde ◽

Monica Barone ◽

Silvia Turroni ◽

Patrizia Brigidi ◽

Enver Keleszade ◽

...

Keyword(s):

Gut Microbiota ◽

Healthy Donor ◽

16S Rrna Gene Sequencing ◽

Chlorella Pyrenoidosa ◽

In Vivo Studies ◽

Rrna Gene ◽

In Vitro Fermentation ◽

The Impact

The response of a coeliac and a healthy gut microbiota to the green algae Chlorella pyrenoidosa was evaluated using an in vitro continuous, pH controlled, gut model system, which simulated the human colon. The effect of C. pyrenoidosa on the microbial structure was determined by 16S rRNA gene sequencing and inferred metagenomics, whereas the metabolic activitywas determined by1H-nuclear magnetic resonancespectroscopic analysis. The addition of C. pyrenoidosa significantly increased the abundance of the genera Prevotella, Ruminococcus and Faecalibacterium in the healthy donor, while an increase in Faecalibacterium, Bifidobacterium and Megasphaera and a decrease in Enterobacteriaceae were observed in the coeliac donor. C. pyrenoidosa also altered several microbial pathways including those involved in short-chain fatty acid (SCFA) production. At the metabolic level, a significant increase from baseline was seen in butyrate and propionate (p < 0.0001) in the healthy donor, especially in vessels 2 and 3. While acetate was significantly higher in the healthy donor at baseline in vessel 3 (p < 0.001) compared to the coeliac donor, this was markedly decreased after in vitro fermentation with C. pyrenoidosa. This is the first in vitro fermentation study of C. pyrenoidosa and human gut microbiota, however, further in vivo studies are needed to prove its efficacy.

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Diversity, Composition and Functional Inference of Gut Microbiota in Indian Cabbage white Pieris canidia (Lepidoptera: Pieridae)

Life ◽

10.3390/life10110254 ◽

2020 ◽

Vol 10 (11) ◽

pp. 254

Author(s):

Ying Wang ◽

Jianqing Zhu ◽

Jie Fang ◽

Li Shen ◽

Shuojia Ma ◽

...

Keyword(s):

Gut Microbiota ◽

16S Rrna Gene Sequencing ◽

Adult Survival ◽

Rrna Gene ◽

Life Stages ◽

Microbial Composition ◽

Significant Difference ◽

Functional Inference ◽

Rrna Gene Sequencing ◽

Insect Fitness

We characterized the gut microbial composition and relative abundance of gut bacteria in the larvae and adults of Pieris canidia by 16S rRNA gene sequencing. The gut microbiota structure was similar across the life stages and sexes. The comparative functional analysis on P. canidia bacterial communities with PICRUSt showed the enrichment of several pathways including those for energy metabolism, immune system, digestive system, xenobiotics biodegradation, transport, cell growth and death. The parameters often used as a proxy of insect fitness (development time, pupation rate, emergence rate, adult survival rate and weight of 5th instars larvae) showed a significant difference between treatment group and untreated group and point to potential fitness advantages with the gut microbiomes in P. canidia. These data provide an overall view of the bacterial community across the life stages and sexes in P. canidia.

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Gut microbiota markers associated with obesity and overweight in Italian adults

Scientific Reports ◽

10.1038/s41598-021-84928-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Vanessa Palmas ◽

Silvia Pisanu ◽

Veronica Madau ◽

Emanuela Casula ◽

Andrea Deledda ◽

...

Keyword(s):

Gut Microbiota ◽

Relative Abundance ◽

Smoking Status ◽

16S Rrna Gene Sequencing ◽

Normal Weight ◽

Activity Level ◽

Rrna Gene ◽

Illumina Platform ◽

Obesity And Overweight ◽

Rrna Gene Sequencing

AbstractIn the present study, we characterized the distinctive signatures of the gut microbiota (GM) from overweight/obese patients (OB), and normal-weight controls (NW), both of Sardinian origin. Fecal bacterial composition of 46 OB patients (BMI = 36.6 ± 6.0; F/M = 40/6) was analyzed and compared to that of 46 NW subjects (BMI = 21.6 ± 2.1; F/M = 41/5), matched for sex, age and smoking status, by using 16S rRNA gene sequencing on MiSeq Illumina platform. The gut microbial community of OB patients exhibited a significant decrease in the relative abundance of several Bacteroidetes taxa (i.e. Flavobacteriaceae, Porphyromonadaceae, Sphingobacteriaceae, Flavobacterium, Rikenella spp., Pedobacter spp., Parabacteroides spp., Bacteroides spp.) when compared to NW; instead, several Firmicutes taxa were significantly increased in the same subjects (Lachnospiraceae, Gemellaceae, Paenibacillaceae, Streptococcaceae, Thermicanaceae, Gemella, Mitsuokella, Streptococcus, Acidaminococcus spp., Eubacterium spp., Ruminococcus spp., Megamonas spp., Streptococcus, Thermicanus, Megasphaera spp. and Veillonella spp.). Correlation analysis indicated that body fatness and waist circumference negatively correlated with Bacteroidetes taxa, while Firmicutes taxa positively correlated with body fat and negatively with muscle mass and/or physical activity level. Furthermore, the relative abundance of several bacterial taxa belonging to Enterobacteriaceae family, known to exhibit endotoxic activity, was increased in the OB group compared to NW. The results extend our knowledge on the GM profiles in Italian OB, identifying novel taxa linking obesity and intestine.

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Gut microbiota accelerates cisplatin-induced acute liver injury associated with robust inflammation and oxidative stress in mice

Journal of Translational Medicine ◽

10.1186/s12967-021-02814-5 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Shenhai Gong ◽

Yinglin Feng ◽

Yunong Zeng ◽

Huanrui Zhang ◽

Meiping Pan ◽

...

Keyword(s):

Oxidative Stress ◽

16S Rrna ◽

Gut Microbiota ◽

Gene Sequencing ◽

16S Rrna Gene Sequencing ◽

Rrna Gene ◽

Metabolomic Analysis ◽

Rrna Gene Sequencing ◽

And Oxidative Stress

Abstract Background Gut microbiota has been reported to be disrupted by cisplatin, as well as to modulate chemotherapy toxicity. However, the precise role of intestinal microbiota in the pathogenesis of cisplatin hepatotoxicity remains unknown. Methods We compared the composition and function of gut microbiota between mice treated with and without cisplatin using 16S rRNA gene sequencing and via metabolomic analysis. For understanding the causative relationship between gut dysbiosis and cisplatin hepatotoxicity, antibiotics were administered to deplete gut microbiota and faecal microbiota transplantation (FMT) was performed before cisplatin treatment. Results 16S rRNA gene sequencing and metabolomic analysis showed that cisplatin administration caused gut microbiota dysbiosis in mice. Gut microbiota ablation by antibiotic exposure protected against the hepatotoxicity induced by cisplatin. Interestingly, mice treated with antibiotics dampened the mitogen-activated protein kinase pathway activation and promoted nuclear factor erythroid 2-related factor 2 nuclear translocation, resulting in decreased levels of both inflammation and oxidative stress in the liver. FMT also confirmed the role of microbiota in individual susceptibility to cisplatin-induced hepatotoxicity. Conclusions This study elucidated the mechanism by which gut microbiota mediates cisplatin hepatotoxicity through enhanced inflammatory response and oxidative stress. This knowledge may help develop novel therapeutic approaches that involve targeting the composition and metabolites of microbiota.

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Comparison between 16S rRNA and shotgun sequencing data for the taxonomic characterization of the gut microbiota

Scientific Reports ◽

10.1038/s41598-021-82726-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Francesco Durazzi ◽

Claudia Sala ◽

Gastone Castellani ◽

Gerardo Manfreda ◽

Daniel Remondini ◽

...

Keyword(s):

16S Rrna ◽

Gut Microbiota ◽

16S Rrna Gene ◽

Gene Sequencing ◽

16S Rrna Gene Sequencing ◽

Shotgun Sequencing ◽

Rrna Gene ◽

Metagenomic Sequencing ◽

Experimental Conditions ◽

Rrna Gene Sequencing

AbstractIn this paper we compared taxonomic results obtained by metataxonomics (16S rRNA gene sequencing) and metagenomics (whole shotgun metagenomic sequencing) to investigate their reliability for bacteria profiling, studying the chicken gut as a model system. The experimental conditions included two compartments of gastrointestinal tracts and two sampling times. We compared the relative abundance distributions obtained with the two sequencing strategies and then tested their capability to distinguish the experimental conditions. The results showed that 16S rRNA gene sequencing detects only part of the gut microbiota community revealed by shotgun sequencing. Specifically, when a sufficient number of reads is available, Shotgun sequencing has more power to identify less abundant taxa than 16S sequencing. Finally, we showed that the less abundant genera detected only by shotgun sequencing are biologically meaningful, being able to discriminate between the experimental conditions as much as the more abundant genera detected by both sequencing strategies.

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Infant Gut Microbiota Associated with Fine Motor Skills

Nutrients ◽

10.3390/nu13051673 ◽

2021 ◽

Vol 13 (5) ◽

pp. 1673

Author(s):

Inmaculada Acuña ◽

Tomás Cerdó ◽

Alicia Ruiz ◽

Francisco J. Torres-Espínola ◽

Ana López-Moreno ◽

...

Keyword(s):

Gut Microbiota ◽

Infant Development ◽

16S Rrna Gene Sequencing ◽

Fine Motor ◽

Rrna Gene ◽

Neurodevelopmental Outcomes ◽

Gut Colonization ◽

Healthy Infants ◽

Behavioural Characteristics ◽

Rrna Gene Sequencing

BACKGROUND: During early life, dynamic gut colonization and brain development co-occur with potential cross-talk mechanisms affecting behaviour. METHODS: We used 16S rRNA gene sequencing to examine the associations between gut microbiota and neurodevelopmental outcomes assessed by the Bayley Scales of Infant Development III in 71 full-term healthy infants at 18 months of age. We hypothesized that children would differ in gut microbial diversity, enterotypes obtained by Dirichlet multinomial mixture analysis and specific taxa based on their behavioural characteristics. RESULTS: In children dichotomized by behavioural trait performance in above- and below-median groups, weighted Unifrac b-diversity exhibited significant differences in fine motor (FM) activity. Dirichlet multinomial mixture modelling identified two enterotypes strongly associated with FM outcomes. When controlling for maternal pre-gestational BMI and breastfeeding for up to 3 months, the examination of signature taxa in FM groups showed that Turicibacter and Parabacteroides were highly abundant in the below-median FM group, while Collinsella, Coprococcus, Enterococcus, Fusobacterium, Holdemanella, Propionibacterium, Roseburia, Veillonella, an unassigned genus within Veillonellaceae and, interestingly, probiotic Bifidobacterium and Lactobacillus were more abundant in the above-median FM group. CONCLUSIONS: Our results suggest an association between enterotypes and specific genera with FM activity and may represent an opportunity for probiotic interventions relevant to treatment for motor disorders.

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