Investigating obesity‐associated brain inflammation using quantitative water content mapping

Journal of Neuroendocrinology, vol. 32, pp. e12907

Abstract

Abstract There is growing evidence that obesity is associated with inflammation in the brain, which could contribute to the pathogenesis of obesity. In humans, it is challenging to detect brain inflammation in vivo. Recently, quantitative magnetic resonance imaging (qMRI) has emerged as a tool for characterising pathophysiological processes in the brain with reliable and reproducible measures. Proton density imaging provides quantitative assessment of the brain water content, which is affected in different pathologies, including inflammation. We enrolled 115 normal weight, overweight and obese men and women (body mass index [BMI] range 20.1‐39.7 kg m ‐2 , age range 20‐75 years, 60% men) to acquire cerebral water content mapping in vivo using MRI at 3 Tesla. We investigated potential associations between brain water content with anthropometric measures of obesity, body fat distribution and whole‐body metabolism. No global changes in water content were associated with obesity. However, higher water content values in the cerebellum, limbic lobe and sub‐lobular region were detected in participants with higher BMI, independent of age. More specifically, the dorsal striatum, hypothalamus, thalamus, fornix, anterior limb of the internal capsule and posterior thalamic radiation showed the strongest relationship with BMI, independent of age. In a subgroup with available measurements (n = 50), we identified visceral adipose tissue to be the strongest tested link between higher water content values and obesity. Individuals with metabolic syndrome had the highest water content values in the hypothalamus and the fornix. There is accumulating evidence that inflammation of the hypothalamus contributed to obesity‐associated insulin resistance in that area. Whether brain inflammation is a cause or consequence of obesity in humans still needs to be investigated using a longitudinal study design. Using qMRI, we were able to detect marked water content changes in young and older obese adults, which is most likely the result of chronic low‐grade inflammation.

Authors 10

1. Stephanie Kullmann corresponding

   German Center for Diabetes Research · Institute of Diabetes Research · University of Tübingen

   Affiliation as printed

   Department of Internal Medicine IV University of Tübingen Tübingen Germany

   German Center for Diabetes Research (DZD e.V.) Tübingen Germany

   Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen Tübingen Germany

2. Zaheer Abbas Aachen Department of Neurology Faculty of Medicine

   Forschungszentrum Jülich · RWTH Aachen University

   Affiliation as printed

   Department of Neurology Faculty of Medicine RWTH Aachen University Aachen Germany

   Institute of Neuroscience and Medicine – 4 Forschungszentrum Jülich GmbH Jülich Germany

3. Jürgen Machann

   German Center for Diabetes Research · Institute of Diabetes Research · University of Tübingen

   Affiliation as printed

   German Center for Diabetes Research (DZD e.V.) Tübingen Germany

   Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen Tübingen Germany

   Section on Experimental Radiology Department of Diagnostic and Interventional Radiology University of Tübingen Tübingen Germany

4. Nadim Jon Shah Aachen Department of Neurology Faculty of Medicine JARA–BRAIN–Translational Medicine

   Forschungszentrum Jülich · Jülich Aachen Research Alliance · Monash University · RWTH Aachen University

   Affiliation as printed

   Department of Neurology Faculty of Medicine RWTH Aachen University Aachen Germany

   Institute of Neuroscience and Medicine – 4 Forschungszentrum Jülich GmbH Jülich Germany

   Institute of Neuroscience and Medicine – 11 Forschungszentrum Jülich GmbH Jülich Germany

   JARA – BRAIN – Translational Medicine RWTH Aachen University Aachen Germany

   Monash Biomedical Imaging School of Psychological Sciences Monash University Melbourne VIC Australia

   Monash Biomedical Imaging, School of Psychological Sciences, Monash University, Melbourne, VIC, Australia

5. Klaus Scheffler

   Max Planck Institute for Biological Cybernetics · University of Tübingen

   Affiliation as printed

   Department of Biomedical Magnetic Resonance University of Tübingen Tübingen Germany

   Department of High‐Field Magnetic Resonance Max Planck Institute for Biological Cybernetics Tübingen Germany

6. Andreas L. Birkenfeld

   German Center for Diabetes Research · Institute of Diabetes Research · University of Tübingen

   Affiliation as printed

   Department of Internal Medicine IV University of Tübingen Tübingen Germany

   German Center for Diabetes Research (DZD e.V.) Tübingen Germany

   Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen Tübingen Germany

7. Hans‐Ulrich Häring

   German Center for Diabetes Research · Institute of Diabetes Research · University of Tübingen

   Affiliation as printed

   Department of Internal Medicine IV University of Tübingen Tübingen Germany

   German Center for Diabetes Research (DZD e.V.) Tübingen Germany

   Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen Tübingen Germany

8. Andreas Fritsche

   German Center for Diabetes Research · Institute of Diabetes Research · University of Tübingen

   Affiliation as printed

   Department of Internal Medicine IV University of Tübingen Tübingen Germany

   German Center for Diabetes Research (DZD e.V.) Tübingen Germany

   Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen Tübingen Germany

9. Martin Heni

   Universitätsklinikum Tübingen · German Center for Diabetes Research · Institute of Diabetes Research · University of Tübingen

   Affiliation as printed

   Department of Internal Medicine IV University of Tübingen Tübingen Germany

   German Center for Diabetes Research (DZD e.V.) Tübingen Germany

   Institute for Clinical Chemistry and Pathobiochemistry University Hospital Tübingen Tübingen Germany

   Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen Tübingen Germany

10. Hubert T. Preissl

    Helmholtz Munich · German Center for Diabetes Research · Institute of Diabetes Research · University of Tübingen

    Affiliation as printed

    Department of Internal Medicine IV University of Tübingen Tübingen Germany

    Department of Pharmacy and Biochemistry Institute of Pharmaceutical Sciences Eberhard Karls Universität Tübingen Tübingen Germany

    German Center for Diabetes Research (DZD e.V.) Tübingen Germany

    Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen Tübingen Germany

    Institute for Diabetes and Obesity Helmholtz Diabetes Center at Helmholtz Zentrum München German Research Center for Environmental Health (GmbH) Neuherberg Germany