Project description:Necrotizing 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 bacterial infection raise concern. Removal of bacteria from donor feces may reduce this risk while maintaining the NEC-preventive effects. We aimed to assess preclinical efficacy and safety of bacteria-free fecal filtrate transfer (FFT). Using fecal material from healthy suckling piglets, we administered FMT rectally, or cognate FFT either rectally or oro-gastrically to formula-fed preterm, cesarean-delivered piglets as a model for preterm infants, We compared gut pathology and related safety parameters with saline controls, and analyzed ileal mucosal transcriptome to gauge the host e response to FMT and FFT treatments relative to control. Results showed that oro-gastric FFT prevented NEC, 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. Global gene expression of host mucosa responded to FMT but not FFT with increased and decreased bacterial and viral defense mechanisms, respectively. In conclusion, as preterm infants are extremely vulnerable to enteric bacterial infections, rational NEC-preventive strategies 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.
Project description:To reveal an unappreciated mechanism of mitochondrial regulation of skeletal metabolic homeostasis via mitochondria transfer and provide new insights of the mechanism of glucocorticoid-induced osteoporosis progression.
Project description:It is hypothesized that a progressive simulated learning strategy will result in better global clinical performance (e.g., technical, communication) and transfer of endoscopic skill, as compared with a high-fidelity simulation strategy.
Project description:To reveal an unappreciated mechanism of mitochondrial regulation of skeletal metabolic homeostasis via mitochondria transfer and provide new insights of the mechanism of glucocorticoid-induced osteoporosis progression.
Project description:Recent studies have demonstrated that mitochondria can be transferred between different cell types to control metabolic homeostasis. However, whether the mitochondria transfer network occurred in the skeletal system or regulate skeletal metabolic homeostasis in vivo is not fully elucidated. Herein, we found that osteolineage cells transfer mitochondria to CD11b+ myeloid, B220+ lymphoid and hematopoietic stem and progenitor cells (HSPCs), of which monocytes/macrophages received the most transferred mitochondria. This process was inhibited by GC treatment contributing to the progression of glucocorticoid-induced osteoporosis (GIOP). Further analysis demonstrated that osteolineage cells transfer mitochondria to osteoclastic lineage cells via Miro1 mediated direct contact, and altered the glutathione metabolism, leading to the ferroptosis of osteoclastic lineage cells, thus inhibiting osteoclast activities. These findings revealed an unappreciated mechanism of mitochondrial regulation of skeletal metabolic homeostasis via mitochondria transfer and provide new insights of the mechanism of GIOP progression.
Project description:The spatial organization of protein synthesis in the eukaryotic cell is essential for maintaining the integrity of the proteome and the functioning of the cell. Translation on free polysomes or on ribosomes associated with the endoplasmic reticulum has been studied for a long time. More recent data have revealed selective translation of mRNAs in other compartments, in particular at the surface of mitochondria. Although these processes have been described in many organisms, in particular in plants, the mRNA targeting and localized translation mechanisms remain poorly understood. Here, the Arabidopsis thaliana Friendly (FMT) protein is shown to be a cytosolic RNA binding protein that associates with cytosolic ribosomes at the surface of mitochondria. As previously shown (El Zawily et al., 2014), FMT knock-out delays seedling development and causes mitochondrial clustering. The mutation also disrupts the mitochondrial proteome, and the localization of nuclear transcripts encoding mitochondrial proteins at the surface of mitochondria. These data indicate that FMT participates in the localization of mRNAs and their translation at the surface of mitochondria.
Project description:In this randomised placebo-controlled trial, irritable bowel syndrome (IBS) patients were treated with faecal material from a healthy donor (n=8, allogenic FMT) or with their own faecal microbiota (n=8, autologous FMT). The faecal transplant was administered by whole colonoscopy into the caecum (30 g of stool in 150 ml sterile saline). Two weeks before the FMT (baseline) as well as two and eight weeks after the FMT, the participants underwent a sigmoidoscopy, and biopsies were collected at a standardised location (20-25 cm from the anal verge at the crossing with the arteria iliaca communis) from an uncleansed sigmoid. In patients treated with allogenic FMT, predominantly immune response-related genes sets were induced, with the strongest response two weeks after FMT. In patients treated with autologous FMT, predominantly metabolism-related gene sets were affected.
Project description:Formyltransferase lacking mutants exhibit reduced growth rates in exponential phase indicating that the function of certain proteins depends on formylated N-termini but it has remained unclear, which cellular processes are abrogated by the lack of formylation. In order to elucidate how global metabolic processes are affected by the absence of formylated proteins the transcription of the fmt mutant was compared with that of the parental strain. Bacteria were grown under aerobic and anaerobic conditions and harvested in the exponential growth phase. Here we have expected the most effects of lacking formyltransferase.