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Hui, Y.

Publications and source records attributed to Hui, Y..

18 recordsLinked to original sources

Transcription factors read a second regulatory code in chromatin

Transcription factors (TFs) decode gene regulatory information written in DNA, yet how this vocabulary is interpreted within chromatin remains largely unexplored. Here, using an upgraded NCAP-SELEX platform, we systematically map the nucleosomal DNA recognition landscapes of 269 human TFs. We uncover a widespread, chromatin-dependent mode of sequence recognition: many TFs recognize motifs on nucleosomal DNA that are distinct from their canonical naked-DNA binding sites, revealing that nucleosome architecture encodes a second gene regulatory code in chromatin. Cryo-electron microscopy structures of TF-nucleosome complexes demonstrate that this second code is read through a combination of nucleosome-induced DNA deformation and direct protein-histone contacts. Functional analyses show that these chromatin-encoded motifs actively promote chromatin accessibility and drive cell-type-specific cis-regulatory activity in vivo. Strikingly, a single TF can deploy its canonical and nucleosome-derived motif repertoires to partition and govern entirely distinct physiological programs. Together, our findings establish that TFs interpret two complementary layers of genomic information: the primary DNA sequence and a second code written into the nucleosome architecture. This chromatin-encoded layer of regulatory information fundamentally expands our understanding of how TF specificity is achieved and how gene regulatory networks are wired in multicellular organisms.

systems biology↗

Probiotic Lactiplantibacillus plantarum VB165 improves metabolic disorders in Insulin-Resistant Mice

This study investigated the effects of Lactiplantibacillus plantarum VB165, a probiotic strain with intrinsic -glucosidase inhibitor (AGI) activity, on metabolic disorders in high-fat diet (HFD)-induced insulin-resistant (IR) mice. Male C57BL/6 mice were divided into four groups: normal control diet (NCD), NCD supplemented with VB165, HFD, and HFD supplemented with VB165. After 16 weeks, VB165 supplementation significantly attenuated HFD-induced weight gain and reduced epididymal and inguinal white adipose tissue indices. VB165 also improved glucose intolerance and insulin resistance (IR), as demonstrated by oral glucose tolerance tests (OGTT) and insulin tolerance tests (ITT), and lowered fasting blood glucose, fasting insulin, and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) levels. Additionally, it ameliorated dyslipidemia by reducing serum total cholesterol, triglycerides, and low-density lipoprotein cholesterol (LDL-C), while alleviating hepatic steatosis and adipocyte hypertrophy. Mechanistically, VB165 enhanced intestinal barrier function by upregulating tight junction proteins (ZO-1 and Occludin), reduced systemic inflammation by lowering LPS, IL-6, and IL-1{beta}. Gut microbiota analysis revealed that VB165 modulated community composition, suppressing HFD-enriched genera (e.g., Ileibacterium and Coriobacteriaceae_UCG_002) and promoting beneficial taxa (e.g., Faecalibaculum and Oscillibacter). These findings demonstrate that L. plantarum VB165 improves HFD-induced metabolic disorders via multi-target mechanisms, highlighting its potential as a probiotic intervention for IR and related metabolic diseases.

microbiology↗

Salmonella hijacks a host glucose transporter for intravacuolar proliferation

AbstractsSalmonella is an intracellular pathogen that resides within a vacuole, which protects it from cytosolic host defenses at the expense of limited nutrient access. Glucose serves as a critical carbon source supporting Salmonellas intracellular replication. However, the molecular mechanisms driving glucose enhancement and the pathways by which cytosolic glucose becomes accessible to intravacuolar Salmonella remain poorly understood. Here, we elucidate a sophisticated three-pronged strategy through which Salmonella hijacks GLUT1 to co-opt host glucose metabolism for pathogenic advantage. Firstly, Salmonella infection upregulates the glucose transporter GLUT1 by activating the MAPK signaling cascade, enhancing host glucose uptake, and accelerating glycolytic flux. Secondly, Salmonella redirects GLUT1 to the bacterial vacuolar membrane to establish a glucose-import conduit that facilitates bacterial acquisition of cytosolic glucose. Thirdly, K29-linked ubiquitination modifications on bacterial vacuolar membranes are a previously unrecognized regulatory mechanism that potentiates GLUT1 transporter activity. Inhibition of GLUT1 potentiates Salmonella-triggered innate immune responses and attenuates bacterial virulence in vitro (RAW264.7 macrophages) and in vivo (murine infection model). Collectively, these findings delineate a novel paradigm of metabolic hijacking, wherein Salmonella systematically rewires host glucose metabolic networks to support intracellular proliferation, providing new insights into host-directed antimicrobial interventions.

microbiology↗

Structural innovations and neurogenic continuity define avian brain development and evolution

Understanding how neurogenic diversity and brain architecture emerge is crucial for deciphering the mechanisms of brain plasticity and cognitive evolution. Here, we present a comprehensive single-cell and spatial transcriptomic atlas of the budgerigar brain, a highly cognitive avian species. We uncover a striking dorsoventral symmetry in excitatory neuron distribution, precisely organized along the lamina mesopallialis intermedia (LMI), a key boundary structure. Cross-species comparisons further reveal the origins of this unique avian pallial organization, offering new insight into avian brain evolution. Our study also highlights distinct developmental trajectories and asynchronous maturation patterns between telencephalic and optic tectum excitatory neurons, underscoring their contribution to innate circuit assembly. Furthermore, we identify adult neural stem cells (NSCs) with evolutionarily conserved transcriptomic signatures across avian species, emphasizing their role in brain plasticity and adaptation. These findings refine fundamental models of avian brain development and elucidate conserved principles of cognitive plasticity.

evolutionary biology↗

Discovery of A Chimeric Polyketide Family as Cancer Immunogenic Chemotherapeutic Leads

Discovery of cancer immunogenic chemotherapeutics represents an emerging, highly promising direction for cancer treatment that uses a chemical drug to achieve the efficacy of both chemotherapy and immunotherapy. Herein we report a high-throughput screening platform and the subsequent discovery of a new class of cancer immunogenic chemotherapeutic leads. Our platform integrates informatics-based activity metabolomics for rapid identification of microbial natural products with both novel structures and potent activities. Additionally, we demonstrate the use of microcrystal electron diffraction (MicroED) for direct structure elucidation of the lead compounds from partially purified mixtures. Using this strategy to screen geographically and phylogenetically diverse microbial metabolites against pseudomyxoma peritonei, a rare and severe cancer, we discovered a new class of leads, aspercyclicins. The aspercyclicins feature an unprecedented tightly packed polycyclic polyketide scaffold that comprises continuous fused, bridged, and spiro rings. The biogenesis of aspercyclicins involves two distinct biosynthetic pathways, leading to formation of chimeric compounds that cannot be predicted by bottom-up approaches mining natural products biosynthetic genes. With comparable potency to some clinically used anticancer drugs, aspercyclicins are active against multiple cancer cell types by inducing immunogenic cell death (ICD), including the release of damage-associated molecular patterns and subsequent phagocytosis of cancer cells. The broad-spectrum ICD-inducing activity of aspercyclicins, combined with their low toxicity to normal cells, represents a new class of potential cancer immunogenic chemotherapeutics and particularly the first drug lead for pseudomyxoma peritonei treatment.

biochemistry↗

Programming aliphatic polyester degradation by engineered bacterial spores

Enzymatic degradation of plastics is a sustainable approach to addressing the growing issue of plastic accumulation. The primary challenges for using enzymes as catalysts are issues with their stability and recyclability, further exacerbated by their costly production and delicate structures. Here, we demonstrate an approach that leverages engineered spores that display target enzymes in high density on their surface to catalyze aliphatic polyester degradation and create self-degradable materials. Engineered spores display recombinant enzymes on their surface, eliminating the need for costly purification processes. The intrinsic physical and biological characteristics of spores enable easy separation from the reaction mixture, repeated reuse, and renewal. Engineered spores displaying lipases completely degrade aliphatic polyesters and retain activity through four cycles, with full activity recovered through germination and sporulation. Directly incorporating spores into polyesters results in robust materials that are completely degradable. Our study offers a straightforward and sustainable biocatalytic approach to plastic degradation.

bioengineering↗

Matching Excellence: ONT's Rise to Parity with PacBio in Genome Reconstruction of Non-Model Bacterium with High GC Content

Reconstruction of complete bacterial genomes is a vital aspect of microbial research, as it provides complex information about genetic content, gene ontology, and regulation. It has become a domain of 3rd generation, long-read sequencing platforms, as short-read technologies can deliver mainly fragmented genomes. PacBio platform can provide high-quality complete genomes, yet remains one of the most expensive sequencing strategies. Oxford Nanopore Technology (ONT) offers the advantage of producing the longest reads, being at the same time the most cost-effective option in terms of platform costs, as well as library preparation, and sequencing. However, ONTs error rate, although significantly reduced lately, still holds a certain level of distrust in the scientific community. In recent years, hybrid assembly of Nanopore and Illumina data has been used to solve ONTs issue with error rate and has yielded the best results in terms of genome completeness, quality, and price. However, the latest advancements in Nanopore technology, including new flow cells (R10.4.1), new library preparation chemistry (V14) and duplex-mode, updated basecallers (Dorado v0.4.1), and the realization that sequencing in dark mode results in significantly increased throughput, have had a significant impact on the quality of generated data and, thus, the recovery of complete genomes by ONT sequencing alone. In this study, we compared the data generated by ONT using three sequencing strategies (Native barcoding, RAPID barcoding, and custom-developed: BARSEQ) against PacBio and Illumina (NextSeq) as well as Illumina-ONT hybrid data. For this purpose, we employed three strains of the actinobacteria Propionibacterium freudenreichii, whose genomes have been proven difficult to reconstruct due to high GC content, regions of repeated sequences and massive genome rearrangements. Our data indicate that DNA libraries prepared with the native barcoding kit, sequenced with V14 chemistry on R10.4.1 flow cell, and assembled with Flye resulted in the reconstruction of complete genomes of overall quality highly similar to that of genomes reconstructed with PacBio. The highest level of quality can be achieved by hybrid assembly of data from the Native barcoding kit complemented with data from custom-developed BARSEQ, both sequenced on R10.4.1 flow cell. In conclusion, our results demonstrate that ONT can be used as a cost-effective sequencing strategy, without the need for complementing with other sequencing technologies, for the reconstruction of complete genomes of the highest quality.

genomics↗

De novo clustering of long-read amplicons improves phylogenetic insight into microbiome data

Long-read amplicon profiling through read classification limits phylogenetic analysis of amplicons while community analysis of multicopy genes, relying on unique molecular identifier (UMI) corrections, often demands deep sequencing. To address this, we present a long amplicon consensus analysis (LACA) workflow employing multiple de novo clustering approaches based on sequence dissimilarity. LACA controls the average error rate of corrected sequences below 1% for the Oxford Nanopore Technologies (ONT) R9.4.1 and ONT R10.3 data, 0.2% for ONT R10.4.1, and 0.1% for high-accuracy ONT Duplex and Pacific Biosciences (PacBio) circular consensus sequencing (CCS) data in both simulated 16S rRNA and real 16-23S rRNA amplicon datasets. In high-accuracy PacBio CCS data, the clustering-based correction matched UMI correction, while outperforming 4xUMI correction in noisy ONT R10.3 and R9.4.1 data. Notably, LACA preserved phylogenetic fidelity in long operational taxonomic units and enhanced microbiome-wide phenotype characterization for synthetic mock communities and human vaginal samples.

bioinformatics↗

An intranasal stringent response vaccine targeting dendritic cells as a novel adjunctive therapy against tuberculosis

Lengthy tuberculosis (TB) treatment is required to address the ability of a subpopulation of persistent Mycobacterium tuberculosis (Mtb) to remain in a non-replicating, antibiotic-tolerant state characterized by metabolic remodeling, including induction of the RelMtb-mediated stringent response. We developed a novel therapeutic DNA vaccine construct involving fusion of the relMtb gene with the immature dendritic cell-targeting gene encoding chemokine MIP-3/CCL20. To augment mucosal immune responses, intranasal delivery was also evaluated. We found that the intramuscular MIP-3/relMtb (fusion) vaccine potentiates isoniazid activity more than a similar DNA vaccine expressing relMtb alone in a chronic TB mouse model (absolute reduction of Mtb burden: 0.63 log10 colony-forming units, P=0.0001), inducing pronounced Mtb-protective immune signatures. The intranasal fusion vaccine, an approach combining relMtb fusion to MIP-3 and intranasal delivery, demonstrated the greatest therapeutic effect compared to each approach alone, as evidenced by robust Th1 and Th17 responses systemically and locally and the greatest mycobactericidal activity when combined with isoniazid (absolute reduction of Mtb burden: 1.13 log10, P<0.0001, when compared to the intramuscular vaccine targeting relMtb alone). This DNA vaccination strategy may be a promising adjunctive approach combined with standard therapy to shorten curative TB treatment, and also serve as proof-of-concept for treating other chronic infections.

immunology↗

Antigen and IL-33 synergistically promote chromatin accessibility at the regulatory regions of pro-inflammatory genes of human skin mast cells

BackgroundAntigenic stimulation through cross-linking the IgE receptor and epithelial cell-derived cytokine IL-33 are potent stimuli of mast cell (MC) activation. Moreover, IL-33 primes a variety of cell types, including MCs to respond more vigorously to external stimuli. However, target genes induced by the combined IL-33 priming and antigenic stimulation have not been investigated in human skin mast cells (HSMCs) in a genome-wide manner. Furthermore, epigenetic changes induced by the combined IL-33 priming and antigenic stimulation have not been evaluated. ResultsWe found that IL-33 priming of HSMCs enhanced their capacity to promote transcriptional synergy of the IL1B and CXCL8 genes by 16- and 3-fold, respectively, in response to combined IL-33 and antigen stimulation compared to without IL-33 priming. We identified the target genes in IL-33-primed HSMCs in response to the combined IL-33 and antigenic stimulation using RNA sequencing (RNA-seq). We found that the majority of genes synergistically upregulated in the IL-33-primed HSMCs in response to the combined IL-33 and antigenic stimulation were predominantly proinflammatory cytokine and chemokine genes. Moreover, the combined IL-33 priming and antigenic stimulation increase chromatin accessibility in the synergy target genes but not synergistically. Transcription factor binding motif analysis revealed more binding sites for NF-{kappa}B, AP-1, GABPA, and RAP1 in the induced or increased chromatin accessible regions of the synergy target genes. ConclusionsOur study demonstrates that IL-33 priming greatly potentiates MCs ability to transcribe proinflammatory cytokine and chemokine genes in response to antigenic stimulation, shining light on how epithelial cell-derived cytokine IL-33 can cause exacerbation of skin MC-mediated allergic inflammation.

immunology↗

Stress-tolerant, recyclable, and autonomously renewable biocatalyst platform enabled by engineered bacterial spores

Here, we describe a stress-tolerant, recyclable, and autonomously renewable biocatalyst platform based on T7 RNA polymerase-enabled high-density protein display on bacterial spores (TIED). TIED uses high-level T7 RNA polymerase-driven expression of recombinant proteins specifically in sporulating cells to allow spontaneous assembly of recombinant fusion proteins on B. subtilis spore surface. TIED enables a high loading density in the range of 106-107 recombinant enzymes per spore, robust catalytic activities of displayed enzymes comparable to the respective free enzymes, and enhanced kinetic stability of displayed enzymes in methanol and elevated temperatures. Further, we demonstrate TIED-enzymes to be not only recyclable, but fully renewable after loss of activity through induction of germination and sporulation, enabling perpetual reuse of these immobilized biocatalysts. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=126 SRC="FIGDIR/small/484680v1_ufig1.gif" ALT="Figure 1"> View larger version (46K): org.highwire.dtl.DTLVardef@6f50d0org.highwire.dtl.DTLVardef@22a9c3org.highwire.dtl.DTLVardef@1b74e9corg.highwire.dtl.DTLVardef@18a11c8_HPS_FORMAT_FIGEXP M_FIG C_FIG Schematic illustration of the T7 RNA polymerase-enabled high-density protein display (TIED) on bacterial spores and its unique features as a biocatalyst platform.

synthetic biology↗

CovidExpress: an interactive portal for intuitive investigation on SARS-CoV-2 related transcriptomes

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in humans could cause coronavirus disease 2019 (COVID-19). Since its first discovery in Dec 2019, SARS-CoV-2 has become a global pandemic and caused 3.3 million direct/indirect deaths (2021 May). Amongst the scientific communitys response to COVID-19, data sharing has emerged as an essential aspect of the combat against SARS-CoV-2. Despite the ever-growing studies about SARS-CoV-2 and COVID-19, to date, only a few databases were curated to enable access to gene expression data. Furthermore, these databases curated only a small set of data and do not provide easy access for investigators without computational skills to perform analyses. To fill this gap and advance open-access to the growing gene expression data on this deadly virus, we collected about 1,500 human bulk RNA-seq datasets from publicly available resources, developed a database and visualization tool, named CovidExpress (https://stjudecab.github.io/covidexpress). This open access database will allow research investigators to examine the gene expression in various tissues, cell lines, and their response to SARS-CoV-2 under different experimental conditions, accelerating the understanding of the etiology of this disease to inform the drug and vaccine development. Our integrative analysis of this big dataset highlights a set of commonly regulated genes in SARS-CoV-2 infected lung and Rhinovirus infected nasal tissues, including OASL that were under-studied in COVID-19 related reports. Our results also suggested a potential FURIN positive feedback loop that might explain the evolutional advantage of SARS-CoV-2.

bioinformatics↗

Gapless indica rice genome reveals synergistic effects of active transposable elements and segmental duplications that promote rice genome evolution

The ultimate goal of genome assembly is a high-accuracy gapless genome. Here we report a new assembly pipeline which we have used to produce a gapless genome for the indica rice cultivar Minghui 63. The 395.82 Mb final assembly is composed of 12 contigs with a contig N50 size of 31.82 Mb. All chromosomes are now gapless, with each chromosome represented by a single contig. This is the first gapless genome assembly achieved for higher plants or animals. BUSCO evaluation showed that gene regions of our assembly have higher completeness than the current rice reference genome (IRGSP-1.0). Compared with japonica rice, indica has more transposable elements (TEs) and segmental duplications (SDs), the latter of which produce many duplicated genes that can affect plant traits through dose effect or sub-/neo-functionalization. The insertion of TEs can also affect the expression of duplicated genes, which may drive evolution of these genes. We also found the expansion of NBS-LRR disease resistance genes and cZOGT growth-related genes in SDs, suggesting that SDs contribute to the adaptative evolution of rice disease resistance and developmental processes. Our findings suggest that active TEs and SDs together provide synergistic effects to promote rice genome evolution.

genomics↗

Comparative analysis of temporal transcriptome reveals the relationship between pectin degradation and pathogenicity of defoliating Verticillium dahliae to Upland cotton (Gossypium hirsutum)

Verticillium wilt (VW), caused by Verticillium dahliae Kleb., is a major plant disease that causes heavy annual losses around the world, especially in Upland cotton (Gossypium hirsutum). The disease-causing pathogen can be classified into defoliating (D) and non-defoliating (ND) pathotypes based on the induced symptoms. At present, little is known about the complex mechanisms of fungal pathogenicity and cotton resistance to it. Comparative analysis of temporal transcriptome was performed on two V. dahliae strains, Vd_086 (D) and Vd_BP2 (ND), at key development stages (hyphal growth, microsclerotia production, and spore germination) to reveal the functional process on plant defoliation and death. Differentially expressed gene (DEG) analysis revealed a strong correlation between cell wall protein kinase activities and the early pathogenicity of defoliating Vd_086. With weighted gene co-expression network analysis (WGCNA), six specific gene modules were correlated with the biological traits of the fungal samples. Functional enrichment with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways together with DEG analysis revealed six pectin degrading enzymes including Polygalacturonase gene 1 (PG1), Pectate lyase gene (PEL) and Pectinesterase gene 1 (PME1) expressed in the early development of Vd_086 that may be related to the robust pathogenicity of this strain during the early invasion. The expression of four of these genes was verified by real-time quantitative reverse transcription PCR (qRT-PCR). In addition, we identified Mitogen-Activated Protein Kinase (MAPK) signaling "hub" genes that may regulate these pectinases. In a word, enhanced expression of pectin degradation enzymes is associated with the stronger pathogenicity of Vd_086 than Vd_BP2, especially at early infection stages. The disease-causing capability is likely regulated by MAPK signaling genes. This study provides new insight into molecular mechanisms of the plant-pathogen interaction on the VW disease, facilitating more effective control measures against this pathogen, including molecular breeding for the VW-resistant cotton cultivars. Author summaryVerticillium wilt (VW), caused by fungal pathogen Verticillium dahliae (Vd), is arguably the most devastating disease in cotton production for decades. Molecular biologists and plant breeders have been working hard to identify host plant resistant genes for many years but have met with little success due to the large complex genome of cotton. The V. dahliae strains are grouped in two pathotypes, of which defoliating (D) strains cause total leaf loss of infected cotton plants and non-defoliating (ND) strains do not. Comparative transcriptome analysis of D strain Vd_086 and ND strain Vd_BP2 identified the candidate genes and molecular mechanisms related to the Vd pathogenicity. Besides the difference in pathogenicity, these strains are distinguishable by the rate of hyphal elongation, microsclerotia production, and spore germination. With these phenotypes, transcriptome sequencing of both strains was performed at the three growth phases. By the combination of comparative transcriptomic differentially expressed gene (DEG) analysis and weighted gene correlation network analysis (WGCNA), cell wall-associated pectinase genes were found to be active at hyphal elongation stage of the V. dahliae pathogen and ribosome-related processes were activated for microsclerotia production. Gene modification processes were activated with many protein kinases at spore germination stage that for the next infection cycle. Furthermore, four pectinases in the pentose and glucuronate interconversion (PGI) pathway were identified and verified as highly expressed in the D strain with strong pathogenicity to Upland cotton (Gossypium hirsutum). Our results provided evidence in support of the hypothesis that stronger early pathogenicity of the D strain is resulted from greater plant cell wall pectin degradability. Transcription factors (TFs) and "hub" module genes were identified in searching of protein interaction for possible regulators of the recognized pectinases. TFs involved in mitogen-activated protein kinase (MAPK) signaling pathway were shown to regulate not only hyphal processes but also the entire growth period of V. dahliae. This is the first study known to use module extraction techniques of WGCNA to identify differentially co-expressed genes between two fungal pathotypes of V. dahliae strains. The study provides new insights into molecular mechanisms of the plant-pathogen interaction and may lead to molecular breeding for resistant cotton cultivars to effectively control this devastating disease.

microbiology↗

Necrotizing enterocolitis-induced systemic immune suppression in neonatal preterm pigs

ObjectivesPreterm infants are at high risks of sepsis and necrotising enterocolitis (NEC). Some develop sepsis shortly after suspected or confirmed NEC, implying that NEC may predispose to sepsis but the underlying mechanisms are unknown. Using NEC-sensitive preterm pigs as models, we investigated the immune status in animals with and without NEC. MethodsPreterm pigs (n=113, caesarean delivered at day 106) were reared until day 5 or 9. Blood was analyzed for T cell subsets, neutrophil phagocytosis, trans criptomics and immune responses to LPS challenge. Gut tissues were used for histology and cytokine analyses. Pigs with/without macroscopic NEC lesions were scored as healthy, mild or severe NEC. ResultsOverall NEC incidence was similar on days 5 and 9 (61-62%) with less severe lesions on day 9, implying gradual mucosal repair following the early phase of NEC on day 5. Pigs with NEC, especially severe NEC, showed decreased goblet cell density and increased MPO+ and CD3+ cell density in the distal intestine or colon. Circulating parameters were minimally affected by NEC on day 5, but widely altered on day 9 in pigs with NEC, especially severe NEC, to the direction of immune suppression. These included elevated Treg frequency, impaired neutrophil phagocytosis, diminished LPS-induced cytokine secretions and immune gene responses, and consistently low expressions of genes related to innate immune signalling and Th1 polarization. ConclusionWe shows evidence for NEC-induced systemic immune suppression, even with mild and sub-clinical NEC lesions, thereby suggesting mechanisms for increased secondary infections in infants with previous NEC diagnosis.

pathology↗

Supplementation of a lacto-fermented rapeseed-seaweed blend promotes gut microbial- and gut immune-modulation in weaner piglets

The direct use of medical zinc oxide (ZnO) in feed will be abandoned after 2022 in Europe, leaving an urgent need for substitutes to prevent post-weaning disorders. This study assessed whether rapeseed meal added two brown macroalagae species (Saccharina latissima and Ascophylum nodosum) and fermented using lactic acid bacteria (FRS) could improve piglet performance and gut health. The weaned piglets were fed one of three different feeding regimens (n = 230 each): basal diet, 2.5% and 5% FRS from day 28 of life to day 85. The piglets fed with 2.5% FRS presented superior phenotype with alleviated intraepithelial and stromal lymphocytes infiltration in the gut, enhanced colon mucosa barrier as well as numerically improvements of final body weight. Colon microbiota composition was determined using amplicon sequencing of the V3 and V1 - V8 region of the 16S rRNA gene using Illumina Nextseq and Oxford Nanopore MinION sequencing, respectively. The two amplicon sequencing strategies showed high consistence between the detected bacteria. Both sequencing technologies showed that the FRS fed piglets had a distinctly different microbial composition relative to the basal diet. Compared with piglets fed the basal diet, Prevotella stercorea was verified by both technologies to be more abundant in the FRS piglets, and positively correlated with colon mucosa thickness and negatively correlated with blood levels of leucocytes and IgG. In conclusion, FRS supplementation improved gut health of weaner piglets, and altered their gut microbiota composition. Increasing the dietary inclusion of FRS from 2.5% to 5% did not cause further improvements.

microbiology↗

Fecal filtrate transfer protects against necrotizing enterocolitis in preterm pigs

Background and aimsNecrotizing enterocolitis (NEC) is an acute and life-threatening gastrointestinal disorder afflicting preterm infants, which is currently unpreventable. Fecal microbiota transplantation (FMT) is a promising preventative therapy, but potential side effects raise concern. Removal of bacteria from donor fecal water may reduce side effects while maintaining wanted effects. We aimed to assess preclinical efficacy and safety of bacteria-free fecal filtrate transfer (FFT). MethodsUsing fecal material from healthy suckling piglets, we administered rectal FMT or cognate FFT by either rectal or oro-gastric administration to formula-fed preterm, cesarean piglets, and compared gut pathology and related safety parameters with saline controls. We then analyzed mucosa and luminal bacterial and viral composition using 16S rRNA gene amplicon and metavirome sequencing, respectively. Finally, we used isolated ileal mucosa, coupled with RNA-Seq, to gauge the host response to the different treatments. ResultsOro-gastric FFT eliminated NEC, which was confirmed by microscopy, whereas FMT did not perform better than control. Moreover, FFT but not FMT reduced intestinal permeability, whereas FMT animals had reduced body weight increase and intestinal growth. Oro-gastric FFT increased viral diversity and reduced Proteobacteria abundance in ileal mucosa relative to control. Global gene expression of host mucosa responded to FMT but not FFT with increased and decreased bacterial and viral defense mechanisms, respectively. ConclusionsAs preterm infants are extremely vulnerable, rational therapies need incontestable safety profiles. Here we show in a clinically relevant animal model that FFT, as opposed to FMT, efficiently prevents NEC without any recognizable side effects. If translatable to preterm infants, this could lead to a change of practice and in turn a reduction in NEC burden.

microbiology↗

Millet-based supplement restored microbiota diversity of acute undernourished pigs

The strong connection between undernutrition and gut microbiota (GM) has enabled microbiota-targeting to become an evolving strategy, which witnessed urgent need for fortified formula of supplementary food in undernutrition therapy. Using undernourished pigs as models, we investigated how corn- and millet-based nutritional supplement acted differently in modulating microbiota. Undernourished pigs at age of 9 weeks were fed with pure maize diet (Maize), corn-based (CSB+) and millet-based (MSB+) supplementary food for 3 weeks. Compared with Maize group, both CSB+ and MSB+ improved serum total protein and globulin level, but no physiological improvement was observed by short-term food intervention. MSB+ shown superior influence on GM immaturity which were more normally-grown like at both structural and functional level. Higher level of Bacteriodetes, Firmicutes and lower level of Preteobacteria were detected in MSB+ fed piglets in contrast with CSB+. Lachnospira.spp was significantly raised after nutritional intervention, indicating high correlation with the undernutrition-associated phenotype. Thus, especially from the GM aspect, millet could be one promising source to help undernourished children reconstruct balanced microbiota in short therapeutic term.

microbiology↗