Gender assessment of the gut microbiome in obese patients

The aim. To assess the relationship between body mass index (BMI) and gut bacteria in men and women with obesity.Materials and methods. The study included 56 overweight patients, divided into 2 groups. The first group consisted of 27 women (the average age was 62 ± 2.2 years), the second group — 29 men (the average age was 55 ± 9 years). The Quetelet index (kg / m2) was calculated for all patients. To study the gut microbiome, the method of polymerase chain reaction in real time (RT-PCR) and metagenomic sequencing were used. DNA from feces was isolated using the Express-DNA-Bio DNA isolation kit (AlkorBio, Russia). To carry out RT-PCR, a set of reagents “Colonoflor-16” (“Alfalab”, Russia) was used. For microbiome sequencing, DNA libraries were prepared using the Illumina Nextera Sample Preparation Kit with DNA primers corresponding to the V3 — V4 regions of the 16S rRNA gene. The study of fecal samples was carried out using 16S rRNA gene sequencing on the Illumina platform (MiSeq sequencer).Results. It was revealed that a higher total number of bacteria, an increased content of Bacteroides fragilis group and Faeca-libacterium prausnitzii, is statistically significantly more common in women than in men. Strong negative correlations were found between BMI and total bacterial mass, between BMI and the number of Bacteroides fragilis group among women with grade I obesity. In overweight men, a correlation was found between BMI and the Bacteroides fragilis group / Faecalibacterium prausnitzii ratio.Conclusions. The total number of bacteria, the content of Bacteroides fragilis group and Faecalibacterium prausnitzii in the gut of patients have statistically significant associations with BMI, and probably can affect the formation of metabolic disorders to a greater extent in women than in men. To clarify the identified trends and patterns in this pilot study, further study of the microbiome with a large number of patients and additional analyzes of the metagenome (16S rRNA) and metabolome, a transcriptome, allowing to control the expression of key metabolic enzymes, largely associated with the compositional features of the gut microbiocenosis, is required.

The Prebiotic Effects of Oats on Blood Lipids, Gut Microbiota, and Short-Chain Fatty Acids in Mildly Hypercholesterolemic Subjects Compared With Rice: A Randomized, Controlled Trial

Phytochemicals derived from oats are reported to possess a beneficial effect on modulating dyslipidemia, specifically on lowering total and LDL cholesterol. However, deeper insights into its mechanism remain unclear. In this randomized controlled study, we assigned 210 mildly hypercholesterolemic subjects from three study centers across China (Beijing, Nanjing, and Shanghai) to consume 80 g of oats or rice daily for 45 days. Plasma lipid profiles, short chain fatty acids (SCFAs), and fecal microbiota were measured. The results showed that total cholesterol (TC) and non-high-density lipoprotein cholesterol (non-HDL-C) decreased significantly with both oats and rice intake after 30 and 45 days. The reduction in TC and non-HDL-C was greater in the participants consuming oats compared with rice at day 45 (p = 0.011 and 0.049, respectively). Oat consumption significantly increased the abundance of Akkermansia muciniphila and Roseburia, and the relative abundance of Dialister, Butyrivibrio, and Paraprevotella, and decreased unclassified f-Sutterellaceae. In the oat group, Bifidobacterium abundance was negatively correlated with LDL-C (p = 0.01, r = −0.31) and, TC and LDL-C were negatively correlated to Faecalibacterium prausnitzii (p = 0.02, r = −0.29; p = 0.03, r = −0.27, respectively). Enterobacteriaceae, Roseburia, and Faecalibacterium prausnitzii were positively correlated with plasma butyric acid and valeric acid concentrations and negatively correlated to isobutyric acid. HDL-C was negatively correlated with valeric acid (p = 0.02, r = −0.25) and total triglyceride (TG) was positively correlated to isovaleric acid (p = 0.03, r = 0.23). Taken together, oats consumption significantly reduced TC and LDL-C, and also mediated a prebiotic effect on gut microbiome. Akkermansia muciniphila, Roseburia, Bifidobacterium, and Faecalibacterium prausnitzii, and plasma SCFA correlated with oat-induced changes in plasma lipids, suggesting prebiotic activity of oats to modulate gut microbiome could contribute towards its cholesterol-lowering effect.

Possible Benefits of Faecalibacterium prausnitzii for Obesity-Associated Gut Disorders

Metabolic disorders are an increasing concern in the industrialized world. Current research has shown a direct link between the composition of the gut microbiota and the pathogenesis of obesity and diabetes. In only a few weeks, an obesity-inducing diet can lead to increased gut permeability and microbial dysbiosis, which contributes to chronic inflammation in the gut and adipose tissues, and to the development of insulin resistance. In this review, we examine the interplay between gut inflammation, insulin resistance, and the gut microbiota, and discuss how some probiotic species can be used to modulate gut homeostasis. We focus primarily on Faecalibacterium prausnitzii, a highly abundant butyrate-producing bacterium that has been proposed both as a biomarker for the development of different gut pathologies and as a potential treatment due to its production of anti-inflammatory metabolites.

The features of the composition of the gut microbiota in patients with hypertension and abdominal obesity

The aim of this work was to study the features of the composition of the gut microbiota (GM) in patients with arterial hypertension (AH), which occurs against the background of abdominal obesity (AO). Materials and methods. The paper presents the data on examination of 70 patients with AH of 2–3 degrees (46 patients with AO and 24 patients without obesity – with normal body weight (NBW)). The control group included 20 apparently healthy individuals with NBW. The patients underwent detailed standard clinical, laboratory and instrumental examination. Determination of the quantitative composition of GM was carried out by the method of polymerase chain reaction with hybridization-fluorescence detection of results in real time using the test system “COLONOFLOR-16 (biocenosis)” (“ALFA-LAB”). In this work, a statistical analysis of the obtained data was carried out using standard methods and Microsoft Excel 17.0. Results. A significant change in the composition of GM were found in patients with AH, which proceeds against the background of AO, in comparison with apparently healthy individuals and with patients with AH without obesity (with NBW). In the group of AH patients with the presence of AO, significant decrease in the number of Lactobacillus spp., Bifidobacterium spp., Faecalibacterium prausnitzii and Аkkermansia muciniphila was found in comparison with apparently healthy individuals. The number of Faecalibacterium prausnitzii and Аkkermansia muciniphila in these patients was also significantly lower than in hypertensive patients with NBW. At the same time, the ratio of Bacteroides fragilis/Faecalibacterium prausnitzii was significantly higher than in the control group and the group of hypertensive patients without obesity – with NBW. Conclusions. The results of the study indicate a possible role for the deficiency of such representatives of GM as Lactobacillus spp., Bifidobacterium spp., Faecalibacterium prausnitzii and Аkkermansia muciniphila and an increase in the ratio of Bacteroides fragilis/Faecalibacterium prausnitzii in the pathogenesis of AH, which occurs against the background of AO.

Tianwang Buxin Granules Influence the Intestinal Flora in Perimenopausal Insomnia

Study Objectives. To study the relationship between perimenopausal insomnia (PI) and intestinal flora and the potential mechanism of Tianwang Buxin granules (TWBXG) in exerting its clinical efficacy. Methods. The subjects included 13 PI patients from the Hubei Provincial Hospital of TCM, Hubei University of TCM, and Wuhan Traditional Chinese Medicine Hospital, and the corresponding noninsomniac spouses of the patients were selected as controls. TWBXG was continuously administered for 4 weeks. The feces of PI patients and their noninsomniac spouses before and after treatment with TWBXG were collected. The intestinal flora composition of each group was detected by metagenomic sequencing, and the efficacy of TWBXG was evaluated by the PSQI scale. Results. Compared with the control group, the model group showed an increase in the abundance of Roseburia faecis, Ruminococcus, Prevotella copri, Fusicatenibacter saccharivorans, and Blautia obeum, while those of Bacteroides, fecal Bacteroidetes, and Faecalibacterium prausnitzii were decreased. Compared with pretreatment, the PSQI score was significantly reduced ( P < 0.05 ), the abundance of Bacteroides, fecal Bacteroidetes, and Faecalibacterium prausnitzii increased, and that of Roseburia faecis, Ruminococcus, Prevotella copri, Fusicatenibacter saccharivorans, and Blautia obeum decreased after treatment. However, there was still a certain gap in the abundance of related flora in the treatment group compared with the control. Conclusion. PI is associated with disturbances in the intestinal flora and is mainly related to the disorders of Roseburia faecis, Ruminococcus, Prevotella copri, Fusicatenibacter saccharivorans, Blautia obeum, Bacteroides, fecal Bacteroidetes, and Faecalibacterium prausnitzii. TWBXG can effectively treat PI, and its effect may be achieved by regulating the disordered intestinal flora. Clinical Trials. The study was registered in the Chinese clinical trial registry and approved by the World Health Organization clinical trial registration platform (Effects of the modified Tianwang Buxin granule and modified Tianwang Buxin decoction pieces on insomnia: a randomized, controlled trial, ChiCTR-IPR-17011549).

A Six-Day, Lifestyle-Based Immersion Program Mitigates Cardiovascular Risk Factors and Induces Shifts in Gut Microbiota, Specifically Lachnospiraceae, Ruminococcaceae, Faecalibacterium prausnitzii: A Pilot Study

Cardiovascular disease (CVD) prevalence remains elevated globally. We have previously shown that a one-week lifestyle “immersion program” leads to clinical improvements and sustained improvements in quality of life in moderate to high atherosclerotic CVD (ASCVD) risk individuals. In a subsequent year of this similarly modeled immersion program, we again collected markers of cardiovascular health and, additionally, evaluated intestinal microbiome composition. ASCVD risk volunteers (n = 73) completed the one-week “immersion program” involving nutrition (100% plant-based foods), stress management education, and exercise. Anthropometric measurements and CVD risk factors were compared at baseline and post intervention. A subgroup (n = 22) provided stool, which we analyzed with 16S rRNA sequencing. We assessed abundance changes within-person, correlated the abundance shifts with clinical changes, and inferred functional pathways using PICRUSt. Reductions in blood pressure, total cholesterol, and triglycerides, were observed without reduction in weight. Significant increases in butyrate producers were detected, including Lachnospiraceae and Oscillospirales. Within-person, significant shifts in relative abundance (RA) occurred, e.g., increased Lachnospiraceae (+58.8% RA, p = 0.0002), Ruminococcaceae (+82.1%, p = 0.0003), Faecalibacterium prausnitzii (+54.5%, p = 0.002), and diversification and richness. Microbiota changes significantly correlated with body mass index (BMI), blood pressure (BP), cholesterol, high-sensitivity C-reactive protein (hsCRP), glucose, and trimethylamine N-oxide (TMAO) changes. Pairwise decreases were inferred in microbial genes corresponding to cancer, metabolic disease, and amino acid metabolism. This brief lifestyle-based intervention improved lipids and BP and enhanced known butyrate producers, without significant weight loss. These results demonstrate a promising non-pharmacological preventative strategy for improving cardiovascular health.

A higher bacterial inward BCAA transport driven by Faecalibacterium prausnitzii is associated with lower serum levels of BCAA in early adolescents

Background Elevations of circulating branched-chain amino acids (BCAA) are observed in humans with obesity and metabolic comorbidities, such as insulin resistance. Although it has been described that microbial metabolism contributes to the circulating pool of these amino acids, studies are still scarce, particularly in pediatric populations. Thus, we aimed to explore whether in early adolescents, gut microbiome was associated to circulating BCAA and in this way to insulin resistance. Methods Shotgun sequencing was performed in DNA from fecal samples of 23 early adolescents (10–12 years old) and amino acid targeted metabolomics analysis was performed by LC–MS/MS in serum samples. By using the HUMAnN2 algorithm we explored microbiome functional profiles to identify whether bacterial metabolism contributed to serum BCAA levels and insulin resistance markers. Results We identified that abundance of genes encoding bacterial BCAA inward transporters were negatively correlated with circulating BCAA and HOMA-IR (P < 0.01). Interestingly, Faecalibacterium prausnitzii contributed to approximately ~ 70% of bacterial BCAA transporters gene count. Moreover, Faecalibacterium prausnitzii abundance was also negatively correlated with circulating BCAA (P = 0.001) and with HOMA-IR (P = 0.018), after adjusting for age, sex and body adiposity. Finally, the association between Faecalibacterium genus and BCAA levels was replicated over an extended data set (N = 124). Conclusions We provide evidence that gut bacterial BCAA transport genes, mainly encoded by Faecalibacterium prausnitzii, are associated with lower circulating BCAA and lower insulin resistance. Based on the later, we propose that the relationship between Faecalibacterium prausnitzii and insulin resistance, could be through modulation of BCAA.