METHODS: Adult patients undergoing pelvic radiation were recruited and randomly assigned to receive supplementation of either 10 g of PHGG or placebo (maltodextrin) twice daily, 14 days prior and 14 days during pelvic radiation. Diarrhea frequency, fecal samples, nutrition status, and QoL were assessed at baseline and days 14, 28 (2 weeks after pelvic radiation), and 45 (at the completion of pelvic radiation, 2 weeks' postsupplementation).
RESULTS: A total of 30 patients (mean age 56.5 ± 10.8 years, 75% malnourished) participated. The mean of diarrhea frequency in the intervention group (IG) was higher compared with the control group (CG) from days 14 and 28 but reduced at day 45. There was a significant intervention effect after controlling for confounders (ie, baseline diarrhea, age, nutrition status) (P < .05). Bifidobacterium count increased by double among the IG at 14 days of PHGG supplementation, whereas such trend was not observed in the CG.
CONCLUSION: Supplementation of PHGG potentially increased the bifidobacterial count and seemed to have post-supplementation effects by reducing the frequency of diarrhea upon the completion of pelvic radiation treatment.
METHODS: We assessed interactions between the taxonomic and functional potential profiles of the gut microbiome (profiled via shotgun metagenomic sequencing), gut transit time (measured via the blue dye method), cardiometabolic health and diet in 863 healthy individuals from the PREDICT 1 study.
RESULTS: We found that gut microbiome taxonomic composition can accurately discriminate between gut transit time classes (0.82 area under the receiver operating characteristic curve) and longer gut transit time is linked with specific microbial species such as Akkermansia muciniphila, Bacteroides spp and Alistipes spp (false discovery rate-adjusted p values <0.01). The blue dye measure of gut transit time had the strongest association with the gut microbiome over typical transit time proxies such as stool consistency and frequency.
CONCLUSIONS: Gut transit time, measured via the blue dye method, is a more informative marker of gut microbiome function than traditional measures of stool consistency and frequency. The blue dye method can be applied in large-scale epidemiological studies to advance diet-microbiome-health research. Clinical trial registry website https://clinicaltrials.gov/ct2/show/NCT03479866 and trial number NCT03479866.
METHODS: Literature search was performed using electronic databases. Relevant studies were identified, extracted and assessed for risk of bias. The primary outcome of this systematic review was the composition of gut microbiota in healthy controls and T2DM while the secondary outcomes included the correlation of gut microbiota with metabolic parameters.
RESULTS: Thirteen case-control studies involving 575 T2DM and 840 healthy controls were included. T2DM patients exhibited a marked increase in lactobacilli. Six studies found lactobacilli to predominate the gut of T2DM patients; however, this could be confounded by the types of antihyperglyacemic medications. Conversely, butyrate producers dominate the gut of healthy controls. In T2DM patients, butyrate producers were surprisingly higher in those taking metformin intake than those not taking the drug. Whilst lactobacilli were found to be higher with increased plasma glucose, conflicting correlations were observed between various genera and anthropometric measurements, dietary intake, lipid profiles and inflammatory markers. There were moderate to strong significant positive correlations between the class Clostridia and phylum Firmicutes with pro-inflammatory IFN-γ as well as between Negativicutes and IL-6.
CONCLUSIONS: Altogether, butyrate-producing bacteria are negatively correlated to glycaemic parameters. Lactobacilli are higher in T2DM patients and Firmicutes is correlated with inflammation.
METHODS AND ANALYSIS: A 2×2 cross-over randomised mechanistic dietary trial will allocate 16 participants with NAFLD to a 2-week either HGI or LGI diet followed by a 4-week wash-out period and then the LGI or HGI diet, alternative to that followed in the first 2 weeks. Baseline and postintervention (four visits) outcome measures will be collected to assess liver fat content (using MRI/S and controlled attenuation parameter-FibroScan), gut microbiota composition (using 16S RNA analysis) and blood biomarkers including glycaemic, insulinaemic, liver, lipid and haematological profiles, gut hormones levels and short-chain fatty acids.
ETHICS AND DISSEMINATION: Study protocol has been approved by the ethics committees of The University of Nottingham and East Midlands Nottingham-2 Research Ethics Committee (REC reference 19/EM/0291). Data from this trial will be used as part of a Philosophy Doctorate thesis. Publications will be in peer-reviewed journals.
TRIAL REGISTRATION NUMBER: NCT04415632.