Alteration of gut microbial composition associated with the therapeutic efficacy of fecal microbiota transplantation in Clostridium difficile infection

BACKGROUND/PURPOSE

Clostridium difficile infection (CDI) leads to a significant cause of hospital-acquired morbidity and mortality. Fecal microbiota transplantation (FMT) is effective to treat recurrent or refractory CDI (rCDI). However, the change of microbial composition contributed by FMT and its association with treatment outcomes is not well determined in Taiwan. We aimed to investigate the efficacy of FMT and the association with microbial alteration endemically.

METHODS

Twelve patients who received FMT for rCDI in Taipei Veterans General Hospital were prospectively enrolled from April 2019 to July 2020. The clinical assessments and fecal microbial analyses in comparison with fecal materials of unrelated donors were conducted before and after FMT.

RESULTS

The overall success rate of FMT for rCDI was 91.7%. A prominence of Proteobacteria, Gammaproteobacteria and Enterobacteriales were observed in the feces of patients with rCDI. Increased fecal phylogenetic diversities and a significant microbial dissimilarity were provided by successful FMT compared to patients before treatment. However, the distinctness was not obvious between patients' feces at baseline and after unsuccessful FMT. Moreover, dynamic change of fecal microbial composition after FMT was observed during follow-up but did not interrupt the treatment effects of FMT.

CONCLUSION

Gut dysbiosis commonly co-exists in patients with rCDI. Restoration of gut microbial communities by FMT provides a promising strategy to treat antibiotic-failed CDI, and the extent of microbial change would be related to the treatment outcomes of FMT. Besides, the effectiveness of FMT for CDI could be maintained even the gut microbiota has diverged over time.

Differences in intestinal microbiota profiling after upper and lower gastrointestinal surgery

BACKGROUND

We aimed to investigate the long-term effects of metabolic profiles and microbiota status in patients after upper gastrointestinal (GI) surgery and lower GI surgery and compared them with a control group.

METHODS

In this cross-sectional study, we analyzed the occurrence of metabolic syndrome (MS) in 10 patients who underwent curative total gastrectomy with Roux-en-Y esophagojejunostomy (RYEJ) anastomosis, 11 patients who underwent curative partial colectomy with right hemicolectomy (RH), and 33 age- and sex-matched controls. Fecal samples were also analyzed by a next-generation sequencing method.

RESULTS

Compared with the control group, the occurrence of MS was significantly lower among patients who underwent total gastrectomy with RYEJ than the controls over the long-term follow-up (>8 years; p < 0.05). Patients who received RH only had a trend of higher serum fasting glucose (p = 0.10). The diversity of the gut microbiota significantly decreased after RH in comparison with the control group and RYEJ group, respectively (p < 0.05). Principal component analysis revealed significant differences between the control, RYEJ, and RH groups (p < 0.001). At the genus level, the ratio of Prevotella to Bacteroides (P/B) was significantly higher in the RYEJ group than in the control group, whereas the P/B ratio was significantly lower in the RH group than in the control group (p < 0.05).

CONCLUSION

Early gastric cancer patients who received total gastrectomy with RYEJ had a lower occurrence of MS than the controls, while early colorectal cancer patients who received RH were associated with a higher serum fasting glucose than the controls during long-term follow-up. In parallel with the metabolic differences, the P/B ratio was also significantly altered in patients after upper and lower GI surgery.

Lactobacillus plantarum PS128 alleviates neurodegenerative progression in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse models of Parkinson's disease

Evidence suggests that the Parkinson's disease (PD) pathogenesis is strongly associated with bidirectional pathways in the microbiota-gut-brain axis (MGBA), and psychobiotics may inhibit PD progression. We previously reported that the novel psychobiotic strain, Lactobacillus plantarum PS128 (PS128), ameliorated abnormal behaviors and modulated neurotransmissions in dopaminergic pathways in rodent models. Here, we report that orally administering PS128 for 4 weeks significantly alleviated the motor deficits, elevation in corticosterone, nigrostriatal dopaminergic neuronal death, and striatal dopamine reduction in 1-methyl-4-phenyl-1,2,3,6-tetrathydropyridine (MPTP)-induced PD mouse models. PS128 ingestion suppressed glial cell hyperactivation and increased norepinephrine and neurotrophic factors in the striatum of the PD-model mice. PS128 administration also attenuated MPTP-induced oxidative stress and neuroinflammation in the nigrostriatal pathway. Fecal analysis showed that PS128 modulated the gut microbiota. L. plantarum abundance was significantly increased along with methionine biosynthesis-related microbial modules. PS128 also suppressed the increased family Enterobacteriaceae and lipopolysaccharide and peptidoglycan biosynthesis-related microbial modules caused by MPTP. In conclude, PS128 ingestion alleviated MPTP-induced motor deficits and neurotoxicity.PS128 supplementation inhibited neurodegenerative processes in PD-model mice and may help prevent PD.

Genome-wide association study identifies novel susceptibility loci for migraine in Han Chinese resided in Taiwan

Background Susceptibility genes for migraine, despite it being a highly prevalent and disabling neurological disorder, have not been analyzed in Asians by genome-wide association study (GWAS). Methods We conducted a two-stage case-control GWAS to identify susceptibility genes for migraine without aura in Han Chinese residing in Taiwan. In the discovery stage, we genotyped 1005 clinic-based Taiwanese migraine patients and 1053 population-based sex-matched controls using Axiom Genome-Wide CHB Array. In the replication stage, we genotyped 27 single-nucleotide polymorphisms with p < 10^-4 in 1120 clinic-based migraine patients and 604 sex-matched normal controls by using Sequenom. Variants at LRP1, TRPM8, and PRDM, which have been replicated in Caucasians, were also genotyped. Results We identified a novel susceptibility locus (rs655484 in DLG2) that reached GWAS significance level for migraine risk in Han Chinese ( p = 1.45 × 10^-12, odds ratio [OR] = 2.42), and also another locus (rs3781545in GFRA1) with suggestive significance ( p = 1.27 × 10^-7, OR = 1.38). In addition, we observed positive association signals with a similar trend to the associations identified in Caucasian GWASs for rs10166942 in TRPM8 (OR = 1.33, 95% confidence interval [CI] = 1.14-1.54, P_permutation = 9.99 × 10^-5; risk allele: T) and rs1172113 in LRP1 (OR = 1.23, 95% CI = 1.04-1.45, P_permutation = 2.9 × 10^-2; risk allele: T). Conclusion The present study is the first migraine GWAS conducted in Han-Chinese and Asians. The newly identified susceptibility genes have potential implications in migraine pathogenesis. DLG2 is involved in glutamatergic neurotransmission, and GFRA1 encodes GDNF receptors that are abundant in CGRP-containing trigeminal neurons. Furthermore, positive association signals for TRPM8 and LRP1 suggest the possibility for common genetic contributions across ethnicities.

The DAO gene is associated with schizophrenia and interacts with other genes in the Taiwan Han Chinese population

BACKGROUND

Schizophrenia is a highly heritable disease with a polygenic mode of inheritance. Many studies have contributed to our understanding of the genetic underpinnings of schizophrenia, but little is known about how interactions among genes affect the risk of schizophrenia. This study aimed to assess the associations and interactions among genes that confer vulnerability to schizophrenia and to examine the moderating effect of neuropsychological impairment.

METHODS

We analyzed 99 SNPs from 10 candidate genes in 1,512 subject samples. The permutation-based single-locus, multi-locus association tests, and a gene-based multifactorial dimension reduction procedure were used to examine genetic associations and interactions to schizophrenia.

RESULTS

We found that no single SNP was significantly associated with schizophrenia. However, a risk haplotype, namely A-T-C of the SNP triplet rsDAO7-rsDAO8-rsDAO13 of the DAO gene, was strongly associated with schizophrenia. Interaction analyses identified multiple between-gene and within-gene interactions. Between-gene interactions including DAO*DISC1 , DAO*NRG1 and DAO*RASD2 and a within-gene interaction for CACNG2 were found among schizophrenia subjects with severe sustained attention deficits, suggesting a modifying effect of impaired neuropsychological functioning. Other interactions such as the within-gene interaction of DAO and the between-gene interaction of DAO and PTK2B were consistently identified regardless of stratification by neuropsychological dysfunction. Importantly, except for the within-gene interaction of CACNG2, all of the identified risk haplotypes and interactions involved SNPs from DAO.

CONCLUSIONS

These results suggest that DAO, which is involved in the N-methyl-d-aspartate receptor regulation, signaling and glutamate metabolism, is the master gene of the genetic associations and interactions underlying schizophrenia. Besides, the interaction between DAO and RASD2 has provided an insight in integrating the glutamate and dopamine hypotheses of schizophrenia.

FASTSNP: an always up-to-date and extendable service for SNP function analysis and prioritization

Single nucleotide polymorphism (SNP) prioritization based on the phenotypic risk is essential for association studies. Assessment of the risk requires access to a variety of heterogeneous biological databases and analytical tools. FASTSNP (function analysis and selection tool for single nucleotide polymorphisms) is a web server that allows users to efficiently identify and prioritize high-risk SNPs according to their phenotypic risks and putative functional effects. A unique feature of FASTSNP is that the functional effect information used for SNP prioritization is always up-to-date, because FASTSNP extracts the information from 11 external web servers at query time using a team of web wrapper agents. Moreover, FASTSNP is extendable by simply deploying more Web wrapper agents. To validate the results of our prioritization, we analyzed 1569 SNPs from the SNP500Cancer database. The results show that SNPs with a high predicted risk exhibit low allele frequencies for the minor alleles, consistent with a well-known finding that a strong selective pressure exists for functional polymorphisms. We have been using FASTSNP for 2 years and FASTSNP enables us to discover a novel promoter polymorphism. FASTSNP is available at .