Imaging Mass Spectrometry Reveals Alterations in N-linked glycosylation that are Associated with Histopathological Changes in Non-alcoholic Steatohepatitis in Mouse and Human

Shaaron Ochoa-Rios (1) , Ian P O’connor (1) , Lindsey N Kent (2) , Julian M Clouse (3) , Yannis Hadjiyannis (3) , Christopher Koivisto (1) , Thierry Pecot (4) , Peggi Angel (1) , Richard R Drake (1) , Gustavo Leone (1, 5) , Anand S Mehta (1) , Don C Rockey (1)

1 MUSC - Medical University of South Carolina [Charleston]
2 WUSTL - Washington University in Saint Louis
3 OSU - Ohio State University [Columbus]
4 SFR UMS CNRS 3480 - INSERM 018 - Biosit : biologie, santé, innovation technologique
5 MCW - Medical College of Wisconsin [Milwaukee]

Non-alcoholic steatohepatitis (NASH) is the progressive form of non-alcoholic fatty liver disease (NAFLD) and is characterized by inflammation, hepatocyte injury, and fibrosis. Further, NASH is a risk factor for cirrhosis and hepatocellular carcinoma (HCC). Previous research demonstrated that serum N-glycan profiles can be altered in NASH patients. Here, we hypothesized that these N-glycan modifications may be associated with specific liver damage in NAFLD and NASH. To investigate the N-glycome profile in tissue, Imaging Mass Spectrometry (IMS) was used for a qualitative and quantitative in situ N-linked glycan analysis of mouse and human NAFLD/NASH tissue. A murine model was used to induce NAFLD and NASH through ad libitum feeding with either a high-fat diet (HFD) or a Western diet (WD), respectively. Mice fed a HFD or WD developed inflammation, steatosis, and fibrosis, consistent with NAFLD/NASH phenotypes. Induction of NAFLD/NASH for 18 months using high caloric diets resulted in increased expression of mannose, complex/fucosylated, and hybrid N-glycan structures compared to control mouse livers. To validate the animal results liver biopsy specimens from 51 human NAFLD/NASH patients representing the full range of NASH CRN (Clinical Research Network) fibrosis stages were analyzed. Importantly, the same glycan alterations observed in mouse models were observed in human NASH biopsies and correlated with the degree of fibrosis. In addition, spatial glycan alterations were localized specifically to histopathological changes in tissue like fibrotic and fatty areas. We demonstrate that the use of standard staining’s combined with IMS provide a full profile of the origin of N-glycan modifications within the tissue. These results indicate that the spatial distribution of abundances of released N-glycans correlate with regions of tissue steatosis associated with NAFLD/NASH.

Domaines: Biochimie [q-bio.BM]

Shaaron Ochoa-Rios, Ian P O’connor, Lindsey N Kent, Julian M Clouse, Yannis Hadjiyannis, et al.. Imaging Mass Spectrometry Reveals Alterations in N-linked glycosylation that are Associated with Histopathological Changes in Non-alcoholic Steatohepatitis in Mouse and Human. Molecular and Cellular Proteomics, 2022, pp.100225. ⟨10.1016/j.mcpro.2022.100225⟩. ⟨hal-03632535⟩