Novel proteomic signatures may indicate MRI-assessed intrahepatic fat state and changes: The DIRECT PLUS clinical trial

Dana T Goldberg; Anat Yaskolka Meir; Gal Tsaban; Ehud Rinott; Alon Kaplan; Hila Zelicha; Nora Klöting; Uta Ceglarek; Berend Iserman; Ilan Shelef; Philip Rosen; Matthias Blüher; Michael Stumvoll; Ohad Etzion; Meir J Stampfer; Frank B Hu; Iris Shai

doi:10.1097/HEP.0000000000000867

Novel proteomic signatures may indicate MRI-assessed intrahepatic fat state and changes: The DIRECT PLUS clinical trial

Hepatology. 2024 Mar 27. doi: 10.1097/HEP.0000000000000867. Online ahead of print.

Authors

Dana T Goldberg¹, Anat Yaskolka Meir^{1

2}, Gal Tsaban¹, Ehud Rinott¹, Alon Kaplan¹, Hila Zelicha¹, Nora Klöting³, Uta Ceglarek^{3

4}, Berend Iserman^{3

4}, Ilan Shelef⁵, Philip Rosen⁵, Matthias Blüher^{3

6}, Michael Stumvoll^{3

6}, Ohad Etzion⁷, Meir J Stampfer^{2

8

9}, Frank B Hu^{2

8

9}, Iris Shai^{1

3

8}

Affiliations

¹ The Health & Nutrition Innovative International Research Center, Department of Epidemiology, Biostatistics and Community Health Sciences, Faculty of Health Sciences, School of Public Health, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
² Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
³ Department of Medicine, University of Leipzig, Leipzig, Germany.
⁴ Institute of Laboratory Medicine, Clinical Chemistry, and Molecular Diagnostics, University of Leipzig Medical Center, Leipzig, Germany.
⁵ Department of Diagnostic Imaging, Soroka University Medical Center, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
⁶ Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany.
⁷ Department of Gastroenterology and Liver Diseases, Soroka University Medical Center, Beersheba, Israel.
⁸ Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
⁹ Department of Medicine, Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.

PMID: 38537153
DOI: 10.1097/HEP.0000000000000867

Abstract

Background and aims: We demonstrated in the randomized 18-month DIRECT PLUS trial (n = 294) that a Mediterranean (MED) diet, supplemented with polyphenol-rich Mankai duckweed, green tea, and walnuts and restricted in red/processed meat, caused substantial intrahepatic fat (IHF%) loss compared with 2 other healthy diets, reducing NAFLD by half, regardless of similar weight loss. Here, we investigated the baseline proteomic profile associated with IHF% and the changes in proteomics associated with IHF% changes induced by lifestyle intervention.

Approach and results: We calculated IHF% by proton magnetic resonance spectroscopy (normal IHF% <5% and abnormal IHF% ≥5%). We assayed baseline and 18-month samples for 95 proteomic biomarkers.Participants (age = 51.3 ± 10.8 y; 89% men; and body mass index = 31.3 ± 3.9 kg/m 2 ) had an 89.8% 18-month retention rate; 83% had eligible follow-up proteomics measurements, and 78% had follow-up proton magnetic resonance spectroscopy. At baseline, 39 candidate proteins were significantly associated with IHF% (false discovery rate <0.05), mostly related to immune function pathways (eg, hydroxyacid oxidase 1). An IHF% prediction based on the DIRECT PLUS by combined model ( R2 = 0.47, root mean square error = 1.05) successfully predicted IHF% ( R2 = 0.53) during testing and was stronger than separately inputting proteins/traditional markers ( R2 = 0.43/0.44). The 18-month lifestyle intervention induced changes in 18 of the 39 candidate proteins, which were significantly associated with IHF% change, with proteins related to metabolism, extracellular matrix remodeling, and immune function pathways. Thrombospondin-2 protein change was higher in the green-MED compared to the MED group, beyond weight and IHF% loss ( p = 0.01). Protein principal component analysis revealed differences in the third principal component time distinct interactions across abnormal/normal IHF% trajectory combinations; p < 0.05 for all).

Conclusions: Our findings suggest novel proteomic signatures that may indicate MRI-assessed IHF state and changes during lifestyle intervention. Specifically, carbonic anhydrase 5A, hydroxyacid oxidase 1, and thrombospondin-2 protein changes are independently associated with IHF% change, and thrombospondin-2 protein change is greater in the green-MED/high polyphenols diet.