Degradation of proteins by the ubiquitin-proteasome system (UPS) is critical for many biological processes. Copper Metabolism gene MURR1 Domain 1 (COMMD1) is a recently identified regulator of hypoxia inducible factor 1a (HIF-1a) protein degradation. As a subunit of the transcription factor hypoxia inducible factor 1 (HIF-1), HIF-1a is the major component of the cellular oxygen sensing system. In vertebrates, HIF-1 is critically involved in many aspects of development and physiology, including placental development. Recently, we demonstrated that Commd1 is essential for normal mouse placental vascularization. COMMD1 physically associates with HIF-1a and reduced COMMD1 expression leads to an increase in HIF-1a protein stability. Based on our observations we hypothesize that Commd1 is a critical regulator of HIF-1 function in placental and vascular development. Here we aim to elucidate the role of Commd1 in HIF-1 signaling during mouse embryogenesis. In the key objectives we will: 1. Elucidate the biochemical mechanisms of the regulation of HIF-1 activity by COMMD1 2. Identify the physiological roles of murine Commd1 during the development of the embryonic and extra-embryonic tissues 3. Asses the role of murine Commd1 in regulating Hif-1 activity during placental development in vitro. Towards these purposes we have developed unique mouse and cell culture models, that will allow us to delineate the physiological and biochemical pathways responsible for the finetuning of Hif-1 activity. A better understanding of the mechanism by which COMMD1 mediates HIF-1a stability will be essential to unravel the biological function of COMMD1 in relation to HIF1 activity, and will contribute to our general understanding of the regulation of protein degradation.

Antibiotics have been unpreceded in the combat against infectious diseases that threatened mankind for centuries, but prolonged exposure causes multidrug-resistance. To reduce antibiotics-use and to support recovery of human and livestock after inevitable antibiotic treatments of infectious disease, we propose to apply or stimulate production of beneficial exopolysaccharides (EPS) by gut microbiota. Depending on its chemical structure, EPS can support microbial colonization, immunity, prevent pathogen adhesion, and recovery after infections. The central hypothesis is: beneficial exopolysaccharides or supporting gut-microbiota that produce specific beneficial EPS can reduce infection and support recovery of antibiotic treatment, and thereby contribute to mitigation of the antibiotic burden. The ultimate goal is to link specific EPS structures to certain beneficial effects. EPS from beneficial bacteria (e.g. Bifidobacteria and Lactobacilli) will be isolated, characterized, synthesized and enzymatically modified to be able to study function-effector relationships. EPS molecules will be tested in vitro for effects on (i) microbiota of different age classes from humans and pigs under antibiotics burden, (ii) prevention of pathogenic adhesion of the model organisms Salmonella enterica Typhimurium and E. coli, (iii) intestinal epithelial barrier-function, and (iv) immunity in complex co-cultures. Next, the effects of specific ingredients of industrial-partners (e.g. GOS, hMOs, resistant starches, pectin) on the microbial production of relevant EPS from humans and animal bacteria (eg Bifidobacteria) after antibiotics exposure will be assessed. The studies will be designed to gain insight into effector-function relationships of effective EPS to prevent pathogen invasion and expedite recovery after antibiotics exposure in humans and pigs.

Despite its univocal success in fighting infectious diseases, antibiotic-use has to be drastically reduced in humans and livestock because of emerging multidrug-resistance. Here, we propose to accomplish this by enhancing intestinal health and defense by designing specific formulations of dietary-fibers for food and feed. This also prevents side-effects such as damage of antibiotics to microbiota and gut barrier-function. These efforts have to be done in an antibiotics-specific fashion as it is known that beneficial effects of dietary fibers for microbiota is antibiotic-type dependent. The focus will be on resistant starches (RS) including isomaltopolysaccharides and galacto-oligo-saccharides (GOS) for which the proof of principle of attenuation of antibiotics-induced intestinal-damage and reduction of antibiotics-use have been demonstrated. The hypothesis of the proposal is: specific combinations of RS and GOS can prevent and support recovery of mucosal microbiota and barrier function in an antibiotics-specific fashion and addition of these components to food and feed can prevent frequency of infectious diseases and antibiotics usage. RS and GOS will be synthesized in different chemical configurations and tested on (i) effects on human and pig fecal-microbiota under antibiotics exposure, (ii) modulation of epithelial barrier function in the presence and absence of model-pathogens and selected antibiotics, (iii) mucus production in presence and absence of infectious stressors and antibiotics, (iv) on immune-barrier function in complex co-cultures. Finally, (v) a proof of principle of rescuing effects on microbiota of a specific dietary-fiber (combination), after antibiotic treatment will be performed in a human pilot study.

The gastrointestinal tract contains 100 trillion bacteria that turn complex sugars into products that the body needs to maintain optimal metabolism, immune function and mental health. Unfortunately, in Western societies we do not eat enough of these complex sugars, which is why asthma, allergies and diabetes are becoming increasingly common. In the current project, we will investigate how we can have health-promoting products formed by intestinal bacteria in different parts of the intestine by changing complex sugar combinations in food. The expectation is that we can improve peoples metabolism, defenses and learning capacity.