Quantification of hepatic steatosis and fibrosis in pre-clinical mouse models by applying digital image analysis

Abstract

Non-alcoholic fatty liver disease (NAFLD) is a group of liver pathologies and a progressive disease continuum including fatty liver, steatohepatitis, fibrosis, and cirrhosis. 17β-Hydroxysteroid dehydrogenase 13 (Hsd17b13) is a lipid droplet -associated protein expressed in the liver and inhibition of the enzyme is considered as a promising approach to develop treatments for NAFLD and to prevent the development of liver fibrosis. However, the role of Hsd17b13 in NAFLD is not fully understood. The aim of the study was to find out the role of Hsd17b13 enzyme in the development of diet-induced stetosis and fibrosis in a genetically modified pre-clinical mouse model by applying quantitative histology and digital image analysis, and to create an image analysis workflow to measure liver fibrosis in mice. By applying the workflow that was created and validated to reliably measure fibrosis in an open source bioimage analysis software, the level of fibrosis was measured in Hsd17b13 deficient and wildtype mice on choline-deficient, L-amino acid-defined, high fat diet (CDAHFD) and on control diet for different periods. The levels of macro- and microvesicular steatosis were measured in same mice by using a commercial software and by applying a convolutional neural network -based model. Hsd17b13 deficiency seemed to provide a protective effect in the progression of fibrosis in male mice on CDAHFD -diet. In mice on diet for twelve weeks, the level of fibrosis was significantly lower in Hsd17b13 deficient mice compared to wildtype mice. Similar protective effect was not observed in the development of steatosis in same mice.