The Metabolic Research Unit Maastricht (MRUM) is at the forefront of human metabolism research worldwide, and thereby an attractive partner for scientific and industrial collaborations to pave the path for new breakthroughs that help the battle against metabolic ill health. Currently, the Metabolic Research Unit Maastricht (MRUM) consists of two units: The Metabolic Research Unit (MRU) and the Metabolic Imaging Unit (MIU). The Metabolic Research Unit (MRU) contains 20 metabolic rooms conforming to the latest quality standards regarding safety, climate and research infrastructure. A combination of the latest technologies available allows control of- and stability for all subject environment parameters as well as for research equipment parameters. Six metabolic units each with two beds are equipped with custom-made ventilated hood systems (Omnical, Maastricht, The Netherlands), calibrated (syringe) pumps for the infusion of substrates, tracers and pharmaceutical agents, and bed-side blood analysers for the measurement of glucose, lactate and electrolytes. Today, these facilities are routinely used to perform one- or two-step hyperinsulinaemic euglycemic clamps in humans (to determine insulin sensitivity), as well as to perform postprandial metabolic studies in the field of obesity, type 2 diabetes and cardiovascular health, but also to evaluate the metabolic effects of the latest medical interventions (i.e. immunotherapy in cancer and endoscopic lung volume reduction in COPD). MRUM also contains 9 rooms that are specifically tailored to research questions involving the highest-level exercise and body composition assessment (BodPod and underwater weighing, deuterium labeled water). One of the most-prominent features of the MRUM are the 5 climate-controlled respiration chambers (room calorimeters). These rooms are like small hotel rooms (14 m3), equipped with a bed, sink, toilet, computer, TV and DVD player. A respiration chamber allows to study human energy expenditure and substrate oxidation under strictly standardized conditions over a period of 12h up to a few days. Finally, all necessary equipment to perform cardiovascular risk assessment (24h blood pressure, pulse-wave velocity, endothelial function, fundus microvascular analysis, etc.) is available within the MRUM. Additionally, techniques to study adipose tissue and muscle metabolism in detail are available (tissue balance techniques, blood flow measurements and microdialysis).
The facilities of the MRUM are combined with analytical wetlab facilities for the analysis of human samples. These facilities include the Stable Isotopes Research Centre (SIRC) –enabling researchers to incorporate stable isotope techniques in the nutritional, physiological and clinical studies -, mass spectrometry equipment for the analysis of lipids and proteins and for proteomic and lipidomic analysis of small human blood and tissue samples, and thermal desorption (TD)-GC-Thermo Electron Tempus Plus-tof-MS for the measurement of a broad array of volatile organic metabolites to study metabolic disturbances in humans.
Close to the metabolic research unit, the Metabolic Imaging Unit (MIU) is situated, with non-invasive magnetic resonance imaging and spectroscopy facilities housed at the department of Radiology and Nuclear Medicine. The facilities currently encompass 5 MRI scanners (two 3 Tesla systems (of which one digital system (1H-only) and one analogue system (with multinuclei option), two 1,5 Tesla systems (1H-only) and one PET-MRI system (3 Tesla, 1H-only). Magnetic Resonance Spectroscopy (MRS) measurements and fMRI measurements profit from higher magnetic field, therefore, only the 3T systems are used for this purpose and therefore, our current infrastructure in terms of MR systems used for metabolic research encompasses one MRI system with multinuclei options enabling the detection of phosphorous and carbon metabolites and an MRI system (1H-only, so hydrogen metabolites can be detected) and PET-MRI system (1H-only).These systems allow the non-invasive study of tissue metabolism of liver, muscle, heart in humans.
We submitted an application to the second call for proposals of the National Roadmap Large-Scale Research Infrastructure to expand MRUM with (1) a novel research unit for the study of 24h circadian metabolism, (2) an upgrade of the MIU to make it compatible for high-end metabolic research in humans, and (3) the establishment and validation of an innovative respiration room concept for clinical research purposes in the Clinical Research Unit (CRU).