Constitution Of Microbiota Research Articles

Simulated Digestion and Fermentation In Vitro by Obese Human Gut Microbiota of Sulforaphane from Broccoli Seeds.

sulforaphane is a kind of isothiocyanate, which is obtained by hydrolysis of glucosinolate by the unique myrosinase in plants. It has been proved to prevent the occurrence of many chronic diseases, such as obesity, diabetes and cancer. The impact of SFN on obese human gut flora, however, has not been established. In this research, SFN was isolated from broccoli seeds and then refined to achieve 95% purity. Next, an investigation was conducted into the digestion and fermentation processes of SFN. The stability of the SFN in simulated saliva, gastric fluid, and intestinal juice provides evidence that it can reach the gut and be available for utilization by gut microflora. In vitro fermentation of SFN by gut microbes in obese patients results in alteration in constitution of microbiota and production of short chain fatty acids. As the result of SFN ingestion by human gut bacteria, the content of butyric and valeric acids increased 1.21- and 1.46-fold, respectively. In obese human guts, the relative abundances of the beneficial genera including Lactobacillus, Weissella, Leuconosto, Algiphilus and Faecalibacterium significantly increased, whilst the detrimental genera, such as Escherichia-Shigella, Klebsiella, Clostridium_sensu_stricto_1, Sutterella, Megamonas and Proteus drastically declined. Taken together, these findings demonstrate that SFN can be used as a nutraceutical ingredient for obese patients and for improving human health.

Intestinal Microbiota at Neutrophil Engraftment Can Predict Acute Graft-Versus-Host Disease in the Recipients of Allogeneic Hematopoietic Stem Cell Transplantation

Backgrounds: An increasing of researches have demonstrated that intestinal microbiome plays an important role in the development of acute graft-versus-host disease (aGVHD), and loss of microbiota diversity is associated with aGVHD. But whether microbiota might be as a biomarker to predict aGVHD is undetermined. This study investigates the prediction of intestinal microbiota at neutrophil engraftment for occurrence of aGVHD.Methods: We prospectively collected stool and blood samples from 166 patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) at pre-conditioning, day 0 and day 15 post-transplantation. The microbiota in stool were detected by 16S rRNA gene sequencing; the inflammatory factors (TNF-α, IL-6, IL-17A, IL-1β and Lipopolysaccharide (LPS)) in blood by multiplex immunoassays and dynamic turbidimetric methods; and T lymphocyte subsets were tested by flow cytometry. AGVHD was determined by retrospective review of the clinical charts.Results: 141 patients were enrolled into analysis, including 83 in grade 0-I aGVHD (non-aGVHD group) and 58 in grades II-IV aGVHD (aGVHD group). The microbiota diversity was lower in aGVHD group than that in non-aGVHD both at day 0 and day 15 post-transplantation (P = 0.018, 0.009, respectively). The diversity was associated with conditioning (Intensified vs. Standard: medain, 3.39 vs. 3.04 (P = 0.017, day 0); medain, 3.17 vs.1.89 (P = 0.045, day 15)) and β-lactam antibiotics (β-lactam vs. No β-lactam: medain, 3.33 vs. 2.48, P = 0.004 (day 15)). At day 15 post-transplantation, Treg/Th17 cells ratio in blood positively correlated with the microbial diversity(r = 0.217, P = 0.010), but negatively correlated with the levels of TNF-α, IL-17A and LPS (r = -0.226, -0.216, -0.291; P = 0.007, 0.010, < 0.001, respectively). Based on the accumulated microbiota Score of the diversity and the special discriminated constitution (Enterobacteriaceae, Lachnospiraceae, Peptostreptococcaceae and Erysipelotrichaceae) between aGVHD and non-aGVHD groups at day 15, the area under the receiver operator characteristic curve (AUC) of the Score could be used to predict aGVHD (II-IV aGVHD: AUC = 0.75, P < 0.001; III-IV aGVHD: AUC = 0.84, p < 0.001). The Score also correlated with the grades of aGVHD (r = 0.481, P < 0.001).Conclusions: The intestinal microbiota diversity is affected by both conditioning and antibiotics. The constitution of microbiota at neutrophil engraftment was a predictive marker for the subsequent development and grades of aGVHD.Keywords: intestinal microbiota, marker, acute graft-versus-host disease, hematopoietic stem cell transplantation DisclosuresNo relevant conflicts of interest to declare.