Pilot Study on the Use of Rheology and Low Field Nmr to Characterize the Liver of Obese Patients Undergoing Metabolic and Bariatric Surgery

International Journal of Molecular Sciences, vol. 27, pp. 4040

Abstract

Background and aims. Liver mechanical properties’ (stiffness/viscoelasticity) evaluation is relevant for diagnosing/monitoring liver fibrosis. Due to limitations of the commonly used elastography, we propose the use of rheology and Low Field-Nuclear Magnetic Resonance (LF-NMR). Methods. In 30 liver samples from patients undergoing bariatric surgery and 18 control samples, we evaluated the shear modulus G/critical stress τc (elastic properties) and mean complex modulus Ga* (elastic/viscous properties) by rheology. LF-NMR was used to measure the spin–spin relaxation time (T2m), reflecting iron content. The expression of iron-related proteins and of pro-fibrotic proteins were evaluated by qRT-PCR. Tissue histology was also determined. Results. Ga*/G/τc were higher in pathological samples, which also showed increased expression of pro-fibrotic proteins. Fibrosis determination displayed a correspondence of 4/30 samples for elastography/histology and 17/30 for rheology/histology. T2m was significantly lower in pathological livers, indicating iron accumulation as confirmed by increased expression of iron-related proteins. T2m was more effective than histology in detecting iron. An inverse correlation was observed between T2m and Ga*/G showing that iron accumulation is associated with increased liver elasticity/viscoelasticity, i.e., fibrosis. Additionally, an inverse correlation of Ga*/G with transferrin, was observed. Conclusion. As our patients mostly have mild liver fibrosis, the combined use of rheology/LF-NMR can effectively detect early changes in liver mechanical properties, aiding in staging and diagnosis of fibrosis.

Authors 14

1. Alice Biasin

   University of Trieste · Ospedale di Cattinara

   Affiliation as printed

   Department of Medical, Surgical and Health Sciences, Cattinara University Hospital, Trieste University, Strada di Fiume 447, I-34149 Trieste, Italy

2. Silvia Palmisano

   University of Trieste · Ospedale di Cattinara

   Affiliation as printed

   Department of Medical, Surgical and Health Sciences, Cattinara University Hospital, Trieste University, Strada di Fiume 447, I-34149 Trieste, Italy

   Surgical Division, Cattinara Hospital, I-34149 Trieste, Italy

3. Michela Abrami

   University of Trieste

   Affiliation as printed

   Department of Engineering and Architecture, Trieste University, Via Valerio 6, I-34127 Trieste, Italy

4. Deborah Bonazza

   Ospedale di Cattinara · Azienda sanitaria universitaria Giuliano Isontina

   Affiliation as printed

   Unit of Surgical Pathology, Cattinara Hospital, Azienda Sanitaria Universitaria Giuliana Isontina (ASUGI), I-34149 Trieste, Italy

5. Fabrizio Zanconati

   University of Trieste · Ospedale di Cattinara

   Affiliation as printed

   Department of Medical, Surgical and Health Sciences, Cattinara University Hospital, Trieste University, Strada di Fiume 447, I-34149 Trieste, Italy

6. Domenico Tierno

   University of Trieste · Ospedale di Cattinara

   Affiliation as printed

   Department of Medical, Surgical and Health Sciences, Cattinara University Hospital, Trieste University, Strada di Fiume 447, I-34149 Trieste, Italy

7. Federica Tonon

   University of Trieste · Ospedale di Cattinara

   Affiliation as printed

   Department of Medical, Surgical and Health Sciences, Cattinara University Hospital, Trieste University, Strada di Fiume 447, I-34149 Trieste, Italy

8. Nhung Hai Truong

   Vietnam National University Ho Chi Minh City · Ho Chi Minh City University of Science

   Affiliation as printed

   Faculty of Biology and Biotechnology, Viet Nam National University, Ho Chi Minh City 700000, Vietnam

   Laboratory of Regenerative Biomedicine, University of Science-VNUHCM, Ho Chi Minh City 700000, Vietnam

9. Thanh Minh Dang

   Vietnam National University Ho Chi Minh City · Ho Chi Minh City University of Science

   Affiliation as printed

   Faculty of Biology and Biotechnology, Viet Nam National University, Ho Chi Minh City 700000, Vietnam

   Laboratory of Regenerative Biomedicine, University of Science-VNUHCM, Ho Chi Minh City 700000, Vietnam

10. Ralf Weiskirchen Aachen Institute of Molecular Pathobiochemistry Experimental Gene Therapy and Clinical Chemistry (IFMPEGKC)

    RWTH Aachen University · Universitätsklinikum Aachen

    Affiliation as printed

    Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry (IFMPEGKC), RWTH University Hospital Aachen, D-52074 Aachen, Germany

11. Fulvia Felluga

    University of Trieste

    Affiliation as printed

    Department of Chemical and Pharmaceutical Sciences, University of Trieste, I-34127 Trieste, Italy

12. Bruna Scaggiante

    University of Trieste

    Affiliation as printed

    Department of Life Sciences, University of Trieste, I-34127 Trieste, Italy

13. Mario Grassi corresponding

    University of Trieste

    Affiliation as printed

    Department of Engineering and Architecture, Trieste University, Via Valerio 6, I-34127 Trieste, Italy

14. Gabriele Grassi corresponding

    University of Trieste · Ospedale di Cattinara

    Affiliation as printed

    Department of Medical, Surgical and Health Sciences, Cattinara University Hospital, Trieste University, Strada di Fiume 447, I-34149 Trieste, Italy