Yinhui Liu

Association between Polycystic Ovary Syndrome and Gut Microbiota

Polycystic ovary syndrome (PCOS) is the most frequent endocrinopathy in women of reproductive age. It is difficult to treat PCOS because of its complex etiology and pathogenesis. Here, we characterized the roles of gut microbiota on the pathogenesis and treatments in letrozole (a nonsteroidal aromatase inhibitor) induced PCOS rat model. Changes in estrous cycles, hormonal levels, ovarian morphology and gut microbiota by PCR-DGGE and real-time PCR were determined. The results showed that PCOS rats displayed abnormal estrous cycles with increasing androgen biosynthesis and exhibited multiple large cysts with diminished granulosa layers in ovarian tissues. Meanwhile, the composition of gut microbiota in letrozole-treated rats was different from that in the controls. Lactobacillus, Ruminococcus and Clostridium were lower while Prevotella was higher in PCOS rats when compared with control rats. After treating PCOS rats with Lactobacillus and fecal microbiota transplantation (FMT) from healthy rats, it was found that the estrous cycles were improved in all 8 rats in FMT group, and in 6 of the 8 rats in Lactobacillus transplantation group with decreasing androgen biosynthesis. Their ovarian morphologies normalized. The composition of gut microbiota restored in both FMT and Lactobacillus treated groups with increasing of Lactobacillus and Clostridium, and decreasing of Prevotella. These results indicated that dysbiosis of gut microbiota was associated with the pathogenesis of PCOS. Microbiota interventions through FMT and Lactobacillus transplantation were beneficial for the treatments of PCOS rats.

Intestinal dysbacteriosis induces changes of T lymphocyte subpopulations in Peyer’s patches of mice and orients the immune response towards humoral immunity

The large numbers of human intestinal microorganisms have a highly co-evolved relationship with the immune system. Dysbacteriosis of intestinal microbiota induces alterations of immune responses, and is closely related to disease development. Peyer’s patches are immune sensors in intestine which exert essential functions during development of inflammatory disease. However, interactions between commensal bacteria and PPs have been poorly characterized. In this study, changes of lymphocyte subpopulations and production of cytokines in PPs of mice with intestinal dysbacteriosis were investigated. The ceftriaxone-induced dysbacteriosis caused a notable change in populations of T lymphocytes, their subpopulations in PPs and expressions of various cytokines. Our results suggest intestinal dysbacteriosis in mice reduces immune tolerance in PPs and orients immune response towards humoral immunity.

Long-term use of ceftriaxone sodium induced changes in gut microbiota and immune system

Antibiotic administration, while facilitating clearance of targeted infections, also perturbs commensal microbial communities. Previous studies have all focused on the effects of short term use of antibiotics. Here, we focus on the effects of long term use of antibiotic on gut microbiota and immunity. BALB/c mice received saline or different doses of ceftriaxone sodium (100, 200 and 400 mg/mL) via daily gavage for 150 days. Alterations of fecal microbiota, small intestine histopathology, body weight, spleen index, serum IgG, mucus SIgA, IFN-γ/IL-4 ratio, CD4/CD8 ratio and CD4+CD25+ cells were evaluated. Long term ceftriaxone sodium administration resulted in gut microbiota dysbiosis, intestine histological lesions, growth inhibition, spleen index reducing. The immune defense ability reduced as serum IgG and mucus SIgA decreased significantly. Not only the immune defense, long term ceftriaxone administration also affected immune regulation. The IFN-γ/IL-4 and CD4/CD8 ratios increased, the CD4+CD25+ cells reduced on days 30 and 60 after ceftriaxone administration. However, after 90 days of ceftriaxone administration, the IFN-γ/IL-4, CD4/CD8 ratios and CD4+CD25+ cells restored, which indicated a new balance of immune regulation had been formed. Overall, these findings contribute to our understanding of long term antibiotic administration influencing gut microbiota and immunity.

Transplantation of a bacterial consortium ameliorates trinitrobenzenesulfonic acid-induced colitis and intestinal dysbiosis in rats.

AIM To investigate the effects of a defined bacterial consortium on trinitrobenzenesulfonic acid (TNBS)-induced colitis and intestinal dysbiosis in rats. MATERIALS & METHODS Rats with TNBS-induced colitis were treated with ceftriaxone and/or a mixture of ten bacterial strains isolated from mouse feces for continuous 24 days. Macroscopic and histopathological parameters in colonic tissue were compared, as were myeloperoxidase enzyme activity and cytokine levels. Patterns of intestinal microbiota were assessed by PCR-denaturing gradient gel electrophoresis, the abundance of selected microbial groups was evaluated by qPCR. RESULTS & CONCLUSION Transplantation of the bacterial consortium showed anti-inflammatory activity in the intestines of rats with TNBS-induced colitis and contributed to the rapid re-establishment of intestinal microbial equilibrium. A defined bacterial consortium may be a viable therapeutic option for the treatment inflammatory bowel disease.

Effects of ceftriaxone-induced intestinal dysbacteriosis on dendritic cells of small intestine in mice.

Intestinal microflora plays a pivotal role in the development of the innate immune system and is essential in shaping adaptive immunity. Dysbacteriosis of intestinal microflora induces altered immune responses and results in disease susceptibility. Dendritic cells (DCs), the professional antigen‐presenting cells, have gained increasing attention because they connect innate and adaptive immunity. They generate both immunity in response to stimulation by pathogenic bacteria and immune tolerance in the presence of commensal bacteria. However, few studies have examined the effects of intestinal dysbacteriosis on DCs. In this study, changes of DCs in the small intestine of mice under the condition of dysbacteriosis induced by ceftriaxone sodium were investigated. It was found that intragastric administration of ceftriaxone sodium caused severe dysteriosis in mice. Compared with controls, numbers of DCs in mice with dysbacteriosis increased significantly (P = 0.0001). However, the maturity and antigen‐presenting ability of DCs were greatly reduced. In addition, there was a significant difference in secretion of IL‐10 and IL‐12 between DCs from mice with dysbacteriosis and controls. To conclude, ceftriaxone‐induced intestinal dysbacteriosis strongly affected the numbers and functions of DCs. The present data suggest that intestinal microflora plays an important role in inducing and maintaining the functions of DCs and thus is essential for the connection between innate and adaptive immune responses.

Traditional Herbal Medicine-Derived Sulforaphene LFS-01 Reverses Colitis in Mice by Selectively Altering the Gut Microbiota and Promoting Intestinal Gamma-Delta T Cells

Sulforaphene (LFS-01) is a natural compound derived from traditional herbal medicine. Here, we show that oral administration of LFS-01 is able to dramatically alter the skewed gut microbiota and reverse colitis in model mice associated with an increase of intestinal γδT cells. Through 16S rDNA sequencing, we showed that LFS-01 can selectively suppress enteric pathogens such as Escherichia–Shigella and Helicobacter whereas the protective strains including Lactobacillus and Lachnospiraceae were significantly expanded after LFS-01 treatment. Interestingly, we demonstrated that LFS-01 administration can significantly promote the IL-17+γδT cells in model mice in response to the expanded Lactobacillus. We verified that the intracellular components of Lactobacillus can stimulate the growth of IL-17+γδT cells upon preincubation. The increased IL-17A after LFS-01 treatment in turn recovers the disrupted occludin subcellular location and protects the epithelial barrier in the colon of model mice. Remarkably, LFS-01 does not show apparent toxicity to animals and we demonstrated that LFS-01 also exerts strong protective effects in TNBS-induced colitis rats. Therefore, LFS-01 holds great promise for the treatment of inflammatory bowel disease (IBD) and warrants translation for use in clinical trials. Our work provided a new avenue for the treatment of IBD based on the strategy of harnessing intestinal symbiosis.

Gut Microbiome Associates With Lipid-Lowering Effect of Rosuvastatin in Vivo

Background: Statin has been widely used to treat hyperlipidemia because of its high potency in decreasing cholesterol levels. The present study aimed to examine the lipid-lowering effect of rosuvastatin and the composition, diversity and species abundance of gut microbiome in association with rosuvastatin efficacy. Trial registration: ChiCTR-ORC-17013212 at the First Affiliated Hospital of Dalian Medical University, November 2, 2017. Results: Totally 64 patients with hyperlipidemia were treated with 10 mg/day of rosuvastatin for 4–8 weeks. Blood lipid indicators triglycerides (TG), total cholesterol (TC), high density lipoprotein (HDL), low-density lipoprotein cholesterol (LDL-C) were measured before and after the treatment. Stool samples were collected right after the treatment. Following total DNA extraction and PCR amplification of 16S rRNA gene, Illumina sequencing was performed for gut microbiome identification, classification and characterization. All the patients showed a significant blood lipid reduction after the treatment. The patients were grouped according to parallel manner design. Group I had 33 patients whose blood lipid levels dropped to the normal levels from week 4, with 58.5% reduction in LDL-C and 26.6% reduction in TC. Group II had 31 patients whose blood lipid levels were still above the normal levels after 8 weeks therapy, but with 41.9% reduction in LDL-C and 31.2% reduction in TC. Based on Operational Taxonomic Unit data, Alpha-diversity by Shannon Index was different between the two groups, and beta-diversity by Principle Component Analysis exhibited separated patterns of the two groups. The differences were also observed in the relative-abundance at phylum, family, and genus levels of the two groups. Linear discriminate analysis illustrated that the abundance of 29 taxa was higher in group I, while the abundance of other 13 taxa was higher in group II. Phyla Firmicutes and Fusobacteria had negative correlation to LDL-C level, but Cyanobacteria and Lentisphaerae had a positive correlation to LDL-C level. Moreover, gender and age were also found somehow correlated to microbial community composition. Conclusion: Rosuvastatin therapy had different blood lipid-lowering effect on hyperlipidemia. The gut microbiota exhibited variation in community composition, diversity and taxa in association to rosuvastatin hypolipidemic effect. These results indicate that modulation of gut microflora, especially the negative/positive correlated species might strengthen statin efficacy in statin-inadequate patients.

20 Gut microbiota in human adults with irritable bowel syndrome differs from healthy controls

Background Recent evidence suggests that there is a link between irritable bowel syndrome (IBS) and microbiota in the gut. The onset and maintenance of IBS may be caused by gut microbiota, but the causes of the pathophysiology of this disorder are unknown. Method 25 patients who fulfilled Rome III criteria for IBS and 29 age- and gender-matched healthy controls were chosen in this study. The total bacterial DNA isolated from the two populations was investigated through amplicon pyrosequencing of the V3–V4 regions of the 16S ribosomal RNA gene. Results The composition of bacteria in the groups differed between healthy controls and IBS subgroups from phylum to the genus level. Synergistetes phylum (p=0.016), Bacilli class (p=0.006), Lactobacillales order (p=0.006), Enterobacteriales order (p=0.02), the families Streptococcaceae (p=0.009), Enterobacteriaceae (p=0.02), and Enterococcaceae (p=0.001), and the genera Streptococcus (p=0.002), Enterobacter (p=0), Klebsiella (p=0.006), and Enterococcus (p=0.001) exhibited higher levels in IBS patients compared with healthy controls. By contrast, Clostridia class (p=0.024), Betaproteobacteria class (p=0.019), Clostridiales order (p=0.024), the families Bacteroidaceae (p=0.049), Desulfovibrionaceae (p<<0.01), and Lachnospiraceae (p=0.012), and the genera Bacteroides (p=0.049) and Roseburia (p=0.012) had lower levels in IBS patients. The genera Turicibacter and Collinsella were most abundant in 51–60 year old patients, followed by 31–40 year old IBS patients. We also detected Acinetobacter and Campylobacter belonging to Proteobacteria phylum in female IBS patients, but not in male patients. Conclusion There were differences in faecal microbiota between IBS patients and healthy controls. The faecal microbiota of patients with IBS is associated with significant increases in detrimental and decreases in beneficial bacterial groups. Acknowledgment Supported by grants from National Program on Key Basic Research Project (973 Program, 2013CB531405), and the National Natural Science Foundation of China (NSFC, No. 81641029 and 81370113).