NASH-inducing Diets in Göttingen Minipigs

Henrik D Pedersen; Elisabeth D Galsgaard; Berit Ø Christoffersen; Susanna Cirera; Dorte Holst; Merete Fredholm; Markus Latta

doi:10.1016/j.jceh.2019.09.004

NASH-inducing Diets in Göttingen Minipigs

J Clin Exp Hepatol. 2020 May-Jun;10(3):211-221. doi: 10.1016/j.jceh.2019.09.004. Epub 2019 Sep 21.

Authors

Henrik D Pedersen^{1

2}, Elisabeth D Galsgaard³, Berit Ø Christoffersen³, Susanna Cirera², Dorte Holst³, Merete Fredholm², Markus Latta³

Affiliations

¹ Ellegaard Göttingen Minipigs A/S, Dalmose, Denmark.
² Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark.
³ Global Drug Discovery, Novo Nordisk A/S, Maaloev, Denmark.

Abstract

Background: Owing to the human-like physiology, a minipig model of nonalcoholic steatohepatitis (NASH) could be valuable. Pigs, however, rarely develop substantial hepatic steatosis, even when fed diets with high fat, fructose, and cholesterol (FFC) content. The potential of choline-deficient, amino acid-defined high-fat diets (CDAHFD) was therefore evaluated in Göttingen Minipigs.

Methods: Castrated male Göttingen Minipigs were fed either chow (n = 5) or one of the three NASH diets: FFC (n = 5), CDAHFD with sucrose (CDAHFD-S; n = 4), or fructose (CDAHFD-F; n = 4) for 8 weeks. Liver and blood samples were collected after 2 weeks and at termination.

Results: Compared with chow, the body weight was higher after FFC (9.8 ± 0.4 versus 8.5 ± 1.2 kg; mean ± SD) and less after CDAHFD-S (6.4 ± 0.8 kg) and CDAHFD-F (6.9 ± 0.8 kg). Liver weight per kg body weight was significantly increased in all 3 NASH groups (FFC 2.1 times; and both CDAHFD diets 3.1 times). Histologically, pronounced macrovesicular steatosis developed only in the CDAHFD groups. Inflammation was present in all three NASH groups. In the CDAHFD groups, inflammatory cells formed crown-like structures around steatotic hepatocytes. Sirius red staining revealed mild fibrosis in the two CDAHFD groups with the fibrotic potential being further supported by immunohistochemical staining for activated stellate cells and gene expression analyses. No noticeable differences were found between CDAHFD-S and CDAHFD-F.

Conclusions: Göttingen Minipigs fed CDAHFD developed pronounced steatosis with inflammation around steatotic hepatocytes and incipient fibrosis, thereby showing potential as a model for human NASH. Further studies are needed to investigate the period needed for marked fibrosis to develop.

Keywords: -F, with fructose); ALP, alkaline phosphatase; ALT, alanine transaminase; AST, aspartate transaminase; Animal model; CD45, cluster of differentiation 45; CDAHFD, choline-deficient; Choline; EDTA, ethylenediaminetetraacetic acid; FFC, high-fat, fructose, cholesterol; Fatty liver; Fibrosis; GGT, gamma-glutamyltransferase; GLDH, glutamate dehydrogenase; HE, hematoxylin and eosin; NAFLD, non-alcoholic fatty liver disease; NASH, non-alcoholic steatohepatitis; Porcine; SMA, smooth muscle actin; amino acid defined high-fat diet (-S, with sucrose.