Clinical NEC prevention practices drive different microbiome profiles and functional responses in the preterm intestine

Preterm infants with very low birthweight are at serious risk for necrotizing enterocolitis. To functionally analyse the principles of three successful preventive NEC regimens, we characterize fecal samples of 55 infants (less than 1500 g, n = 383, female = 22) longitudinally (two weeks) with respect to gut microbiome profiles (bacteria, archaea, fungi, viruses; targeted 16S rRNA gene sequencing and shotgun metagenomics), microbial function, virulence factors, antibiotic resistances and metabolic profiles, including human milk oligosaccharides (HMOs) and short-chain fatty acids (German Registry of Clinical Trials, No.: DRKS00009290). Regimens including probiotic Bifidobacterium longum subsp. infantis NCDO 2203 supplementation affect microbiome development globally, pointing toward the genomic potential to convert HMOs. Engraftment of NCDO 2203 is associated with a substantial reduction of microbiome-associated antibiotic resistance as compared to regimens using probiotic Lactobacillus rhamnosus LCR 35 or no supplementation. Crucially, the beneficial effects of Bifidobacterium longum subsp. infantis NCDO 2203 supplementation depends on simultaneous feeding with HMOs. We demonstrate that preventive regimens have the highest impact on development and maturation of the gastrointestinal microbiome, enabling the establishment of a resilient microbial ecosystem that reduces pathogenic threats in at-risk preterm infants

SelfScapes

SelfScapes is a new research cluster at York St John University and refers to the relationship between self and its environment. The aim of this research cluster is to investigate both the body and place as sites for interconnected experiences and how this might be mediated through a range of media. York St John University and the Forestry England staff at Dalby Forest had already established a good working relationship so we decided to base the first SelfScapes events at Dalby Forest. Petra Young, who leads the arts programme for Forestry England at Dalby Forest, gave us the working space and support for the events. SelfScapes was awarded internal research funding from York St John University in 2017 as a means to bring a group of staff and students together to work within a research cluster. The cluster was initiated by Dr Joanna Sperryn-Jones, Mark Adams, Sally Taylor and Dr Christina Kolaiti. The subject of SelfScapes emerged as a common theme from conversations on our individual art practices. SelfScapes focus on the relationship between self and environment seemed like an appropriate starting point for our common interests, which are embodied by an experimental approach to image making and developing ideas. In addition, the form of the event (shared making followed by discussion and an exhibition) is of common interest to us as a means of disseminating and developing artistic research

Silencing of spontaneous activity at α4β1/3δ GABAA receptors in hippocampal granule cells reveals different ligand pharmacology

BACKGROUND AND PURPOSE: The δ‐subunit‐containing GABA(A) receptors, α(4)β(1)δ and α(4)β(3)δ, in dentate gyrus granule cells (DGGCs) are known to exhibit both spontaneous channel openings (i.e. constitutive activity) and agonist‐induced current. The functional implications of spontaneous gating are unclear. In this study, we tested the hypothesis that constitutively active α(4)β(1/3)δ receptors limit agonist efficacy. EXPERIMENTAL APPROACH: Whole‐cell electrophysiological recordings of adult male rat and mouse hippocampal DGGCs were used to characterize known agonists and antagonists at δ‐subunit‐containing GABA(A) receptors. To separate constitutive and agonist‐induced currents, different recording conditions were employed. KEY RESULTS: Recordings at either 24°C or 34°C, including the PKC autoinhibitory peptide (19–36) intracellularly, removed spontaneous gating by GABA(A) receptors. In the absence of spontaneous gating, DGGCs responded to the α(4)β(1/3)δ orthosteric agonist Thio‐THIP with a four‐fold increased efficacy relative to recording conditions favouring constitutive activity. Surprisingly, the neutral antagonist gabazine was unable to antagonize the current by Thio‐THIP. Furthermore, a current was elicited by gabazine alone only when the constitutive current was silenced (EC(50) 2.1 μM). The gabazine‐induced current was inhibited by picrotoxin, potentiated by DS2, completely absent in δ(−/−) mice and reduced in β(1) (−/−) mice, but could not be replicated in human α(4)β(1/3)δ receptors expressed heterologously in HEK cells. CONCLUSION AND IMPLICATIONS: Kinase activity infers spontaneous gating in α(4)β(1/3)δ receptors in DGGCs. This significantly limits the efficacy of GABA(A) agonists and has implications in pathologies involving aberrant excitability caused by phosphorylation (e.g. addiction and epilepsy). In such cases, the efficacy of δ‐preferring GABA(A) ligands may be reduced

MicroRNA mimicry blocks pulmonary fibrosis

Over the last decade, great enthusiasm has evolved for microRNA (miRNA) therapeutics. Part of the excitement stems from the fact that a miRNA often regulates numerous related mRNAs. As such, modulation of a single miRNA allows for parallel regulation of multiple genes involved in a particular disease. While many studies have shown therapeutic efficacy using miRNA inhibitors, efforts to restore or increase the function of a miRNA have been lagging behind. The miR-29 family has gained a lot of attention for its clear function in tissue fibrosis. This fibroblast-enriched miRNA family is downregulated in fibrotic diseases which induces a coordinate increase of many extracellular matrix genes. Here, we show that intravenous injection of synthetic RNA duplexes can increase miR-29 levels in vivo for several days. Moreover, therapeutic delivery of these miR-29 mimics during bleomycin-induced pulmonary fibrosis restores endogenous miR-29 function whereby decreasing collagen expression and blocking and reversing pulmonary fibrosis. Our data support the feasibility of using miRNA mimics to therapeutically increase miRNAs and indicate miR-29 to be a potent therapeutic miRNA for treating pulmonary fibrosis

Use of nanoscale mechanical stimulation for control and manipulation of cell behaviour

The ability to control cell behaviour, cell fate and simulate reliable tissue models in vitro remains a significant challenge yet is crucial for various applications of high throughput screening e.g. drug discovery. Mechanotransduction (the ability of cells to convert mechanical forces in their environment to biochemical signalling) represents an alternative mechanism to attain this control with such studies developing techniques to reproducibly control the mechanical environment in techniques which have potential to be scaled. In this review, the use of techniques such as finite element modelling and precision interferometric measurement are examined to provide context for a novel technique based on nanoscale vibration, also known as “nanokicking”. Studies have shown this stimulus to alter cellular responses in both endothelial and mesenchymal stem cells (MSCs), particularly in increased proliferation rate and induced osteogenesis respectively. Endothelial cell lines were exposed to nanoscale vibration amplitudes across a frequency range of 1–100 Hz, and MSCs primarily at 1 kHz. This technique provides significant potential benefits over existing technologies, as cellular responses can be initiated without the use of expensive engineering techniques and/or chemical induction factors. Due to the reproducible and scalable nature of the apparatus it is conceivable that nanokicking could be used for controlling cell behaviour within a wide array of high throughput procedures in the research environment, within drug discovery, and for clinical/therapeutic applications

DataSheet_1_PET/CT imaging detects intestinal inflammation in a mouse model of doxorubicin-induced mucositis.docx

IntroductionA severe side effect of cancer chemotherapy is the development of gastrointestinal mucositis, characterised by mucosal inflammation. We investigated if 2-deoxy-2-[18F] fluoro-D-glucose positron emission tomography combined with computed tomography (2-[18F]FDG-PET/CT) could visualise gastrointestinal mucositis in mice treated with the chemotherapeutic agent doxorubicin.MethodsIn this study, gastrointestinal inflammation was longitudinally evaluated by 2-[18F]FDG-PET/CT scans before and 1, 3, 6, and 10 days after treatment with doxorubicin. Doxorubicin-treated mice were compared to saline-treated littermates using the abdominal standard uptake value of 2-[18F]FDG corrected for body weight (SUVBW).ResultsAbdominal SUVBW was significantly increased on day 1 (p BW returned to baseline levels on day 10. In the doxorubicin group, the largest weight loss was observed on day 3 (control vs doxorubicin, mean percent of baseline weight: (98.5 ± 3.2% vs 87.9 ± 4.6%, p DiscussionTogether, these findings indicate that sequential 2-[18F]FDG-PET/CT scans can objectively quantify and evaluate the development and resolution of intestinal inflammation over time in a mouse model of doxorubicin-induced mucositis.</p

Video_1_PET/CT imaging detects intestinal inflammation in a mouse model of doxorubicin-induced mucositis.wmv

IntroductionA severe side effect of cancer chemotherapy is the development of gastrointestinal mucositis, characterised by mucosal inflammation. We investigated if 2-deoxy-2-[18F] fluoro-D-glucose positron emission tomography combined with computed tomography (2-[18F]FDG-PET/CT) could visualise gastrointestinal mucositis in mice treated with the chemotherapeutic agent doxorubicin.MethodsIn this study, gastrointestinal inflammation was longitudinally evaluated by 2-[18F]FDG-PET/CT scans before and 1, 3, 6, and 10 days after treatment with doxorubicin. Doxorubicin-treated mice were compared to saline-treated littermates using the abdominal standard uptake value of 2-[18F]FDG corrected for body weight (SUVBW).ResultsAbdominal SUVBW was significantly increased on day 1 (p BW returned to baseline levels on day 10. In the doxorubicin group, the largest weight loss was observed on day 3 (control vs doxorubicin, mean percent of baseline weight: (98.5 ± 3.2% vs 87.9 ± 4.6%, p DiscussionTogether, these findings indicate that sequential 2-[18F]FDG-PET/CT scans can objectively quantify and evaluate the development and resolution of intestinal inflammation over time in a mouse model of doxorubicin-induced mucositis.</p