Size control and electronic manipulation of Ru catalyst over B, N co-doped carbon network for high-performance hydrogen evolution reaction

Microbiota-gut-brain axis is an evident pathway of host-microbiota crosstalk that is linked to multiple brain disorders. Microbiota released extracellular vesicles (MEVs) has emerged as a key player in intercellular signaling in host microbiome communications. However, their role in gutbrain axis signaling is poorly investigated. Here, we performed a deep multi-omics profiling of MEVs content generated ex vivo and from stool samples in order to get some insights on their role in gut-brain-axis signaling. Metabolomics profiling identified a wide array of metabolites embedded in MEVs, including lipids, carbohydrates, amino acids, vitamins, and organic acids. Interestingly, many neurotransmitter-related compounds were detected inside MEVs, including arachidonyl-dopamine (NADA), gabapentin, glutamate and N-acylethanolamines. Next, we aimed to identify commensal microbes with psychobiotic activity. We isolated 58 Bacteroides strains assigned to four genera, 11 species, and 4 new species based on 16S rDNA sequencing. We performed whole genome sequencing of 18 representative isolates, followed by a comparative analysis of the structure of polysaccharide utilization loci (PUL) and glutamate decarboxylase (GAD), a genetic system involved in GABA production. Quantifying GABA was done using competitive ELISA, wherein three isolates (B. finegoldii, B. faecis, and B. caccae) showed high GABA production (4.5-7 mM range) in supernatant whereas 2.2 to 4 uM GABA concentration was detected inside microvesicles extracted using ultracentrifugation. To test the biodistribution of MEVs from the gut to other parts of the body, CACO-2, RIN-14 B, and hCMEC/D3 cells showed a capacity to internalize labeled MEVs through an endocytic mechanism. Additionally, MEVs exhibited a dose dependent paracellular transport through CACO-2 intestinal cells and hCMEC/D3 brain endothelial cells. In vivo results showed biodistribution of MEVs to liver, stomach and spleen. Overall, our results reveal the capabilities of MEVs to cross the intestinal and blood brain barriers to deliver their cargoes of neuroactive molecules to the brain as a new signaling mechanism in microbiota-gut-brain axis communications.

/pdf/comprehensive-multi-omics-characterization-of-gut-microbiome-7q9jp5x5.pdf

Comprehensive multi-omics characterization of gut microbiome extracellular vesicles reveals a connection to gut-brain axis signaling

SCOPE
miR-29a expression patterns influence numerous physiological phenomena. Of note, upregulation of miR-29a ameliorates high-fat diet (HFD)-induced liver dysfunctions in mice. However, the miR-29a effect on gut microbiome composition and HFD-induced gut microbiota changes during metabolic disturbances remains unclear. We provide compelling evidence for the protective role of miR-29a in gut barrier dysfunction and steatohepatitis.


METHODS AND RESULTS
We bred miR-29a overexpressed mice (miR-29aTg) to characterize intestinal, serum biochemical, and fecal microbiota profiling features compared to wild-type mice (WT). Mice were fed an HFD for 8 months to induce steatohepatitis, and intestinal dysfunction was determined via histopathological analysis. miR-29aTg had better lipid metabolism capability that decreased total cholesterol and triglyceride levels in serum than WT of the same age. We further demonstrated that miR-29aTg contributes to intestinal integrity by maintaining periodic acid Schiff positive cell numbers and diversity of fecal microorganisms. HFD-induced bacterial community disturbance and steatohepatitis resulted in more severe WT than miR-29aTg. Gut microorganism profiling revealed Lactobacillus, Ruminiclostridium_9, and Lachnoclostridium enrichment in miR-29aTg and significantly decreased interleukin-6 expression in the liver and intestinal tract.


CONCLUSION
This study provides new evidence that sheds light on the host genetic background of miR-29a, which protects against steatohepatitis and other intestinal disorders. This article is protected by copyright. All rights reserved.

MicroRNA-29a Compromises Hepatic Adiposis and Gut Dysbiosis in High Fat Diet-Fed Mice via Downregulating Inflammation.

N,O-Doped Hierarchical Meso/Microporous Carbon Frameworks Enable Efficient Carbon-Based Supercapacitor

The gut microbiota is now well known to affect the host's immune system. One way of bacterial communication with host cells is via the secretion of vesicles, small membrane structures containing various cargo. Research on vesicles secreted by Gram-positive gut bacteria, their mechanisms of interaction with the host and their immune-modulatory effects are still relatively scarce. Here we characterized the size, protein content, and immune-modulatory effects of extracellular vesicles (EVs) secreted by a newly sequenced Gram-positive human gut symbiont strain - Bifidobacterium longum AO44. We found that B. longum EVs exert anti-inflammatory effects, inducing IL-10 secretion from both splenocytes and dendritic cells (DC)-CD4+ T cells co-cultures. Furthermore, the EVs protein content showed enrichment in ABC transporters, quorum sensing proteins, and extracellular solute-binding proteins, which were previously shown to have a prominent function in the anti-inflammatory effect of other strains of B. longum. This study underlines the importance of bacterial vesicles in facilitating the gut bacterial immune-modulatory effects on the host and sheds light on bacterial vesicles as future therapeutics. 

/pdf/extracellular-vesicles-of-the-gram-positive-gut-symbiont-27i486ud.pdf

Extracellular vesicles of the Gram-positive gut symbiont Bifidobacterium longum induce immune-modulatory, anti-inflammatory effects

Wheat-Like Co3o4 on Carbon Derived from Silk as Anode Materials for Enhanced Lithium Storage

ABSTRACT Intestinal microenvironment dysbiosis is one of the major causes of diseases, such as obesity, diabetes, inflammatory bowel disease, and colon cancer. Microbiota-based strategies have excellent clinical potential in the treatment of repetitive and refractory diseases; however, the underlying regulatory mechanisms remain elusive. Identification of the internal regulatory mechanism of the gut microbiome and the interaction mechanisms involving bacteria-host is essential to achieve precise control of the gut microbiome and obtain effective clinical data. Gut bacteria-derived extracellular vesicles (GBEVs) are lipid bilayer nanoparticles secreted by the gut microbiota and are considered key players in bacteria-bacteria and bacteria-host communication. This review focusses on the role of GBEVs in gut microbiota interactions and bacteria-host communication, and the potential clinical applications of GBEVs.

Gut bacterial extracellular vesicles: important players in regulating intestinal microenvironment

Nematode-trapping fungus (NTF) is a crucial predator of nematodes, which can capture nematodes by developing specific trapping devices. However, there is limited understanding of the role and mechanism of cell surface proteins attached to the surface of mycelia or trapping cells. Here, the effects of a putative GPI-anchored protein-encoding gene Aog185 on the growth and nematode-trapping efficiency of A. oligospora were investigated. Compared to the wild-type (WT) strain, the ΔAog185 mutant grew more slowly, exhibited a 20% decrease in conidiation, delayed conidial germination, generated fewer traps, attenuated nematode trapping efficiency, and was more sensitive to chemical stressors. Transcriptomic analysis indicated that a large number of transmembrane transport-related genes were differentially expressed between the WT and ΔAog185 mutant strains. Aog185 deletion could damage the intrinsic components of the membrane and cytoskeleton. Specifically, knockout of Aog185 disrupted transmembrane transport homeostasis during the phagocytosis, cell autophagy, and oxidative phosphorylation processes, which were associated with the fusion of cells and organelle membranes, transport of ions and substrates, and energy metabolism. Hence, the putative GPI-anchored protein-encoding gene Aog185 may contribute to the lifestyle switch of NTF and nematode capture, and the effect of Aog185 gene on cell transmembrane transport is considered key to this process. Our findings provide new insights into the mechanism of Aog185 gene during the process of nematode trapping by NTF.

Deletion of a Putative GPI-Anchored Protein-Encoding Gene Aog185 Impedes the Growth and Nematode-Trapping Efficiency of Arthrobotrys oligospora by Disrupting Transmembrane Transport Homeostasis

BACKGROUND
Toxoplasma gondii (T. gondii) is not only a threat to the public health but it also poses adverse impacts on the livestock industry. This study aimed to develop a recombinant vaccine composed of T. gondii microneme protein 6 (TgMIC6) and T. gondii rhoptry protein 18 (TgROP18).The vaccine was delivered with a novel vector, named analogous hyaluronic acid chitosan nanoparticle-hydrogel (AHACNP-HG) and its immune protection was evaluated.


METHODS
The recombinant MIC6 and ROP18 proteins were obtained by affinity chromatography and loaded onto AHACNP-HG by magnetic stirring. The characterizations of AHACNP-HG were investigated, including its structure, rheological property, nanoparticle size and zeta potential, its ability to release protein in vitro and toxicology in vivo. The immunological and anti-infection effects of AHACNP-HG/rMIC6/rROP18 were examined in the mice model.


RESULTS
AHACNP-HG presented a characteristic of composite system and possessed biosecurity with excellent protein control-release property. AHACNP-HG/rMIC6/rROP18 vaccine enhanced a mixed Th1/Th2 cellular immune response accompanied by an increased level of the cytokines, IFN-γ and IL-10. It also provoked a stronger humoral immune response. Additionally, after challenge with T. gondii tachyzoite, AHACNP-HG/rMIC6/rROP18 inoculation prolonged the survival time of mice.


CONCLUSION
Our data indicated that mixed rMIC6 and rROP18 induced strong immune response and played a certain protective role in controlling T. gondii infection, and the novel adjuvant AHACNP-HG improved modestly some immunogenicity properties in mouse model, which indicated that it can be used as a novel delivery system in vaccine development.

Immunological evaluation of a recombinant vaccine delivered with an analogous hyaluronic acid chitosan nanoparticle-hydrogel against Toxoplasma gondii in mice.

Xiao Liang

Papers

Wheat-Like Co3o4 on Carbon Derived from Silk as Anode Materials for Enhanced Lithium Storage

Gut bacterial extracellular vesicles: important players in regulating intestinal microenvironment

Deletion of a Putative GPI-Anchored Protein-Encoding Gene Aog185 Impedes the Growth and Nematode-Trapping Efficiency of Arthrobotrys oligospora by Disrupting Transmembrane Transport Homeostasis

Immunological evaluation of a recombinant vaccine delivered with an analogous hyaluronic acid chitosan nanoparticle-hydrogel against Toxoplasma gondii in mice.

High Fluorescent N-Doped Carbon Dots Derived from Sanghuangporus Lonicericola for Detecting Tetracyclines in Aquaculture Water and Rat Serum Samples