Title
Key Inflammatory Processes in Human NASH Are Reflected in Ldlr-/-.Leiden Mice: A Translational Gene Profiling Study
Author
Morrison, M.C.
Kleemann, R.
van Koppen, A.
Hanemaaijer, R.
Verschuren, L.
Publication year
2018
Abstract
Introduction: It is generally accepted that metabolic inflammation in the liver is an important driver of disease progression in NASH and associated matrix remodeling/fibrosis. However, the exact molecular inflammatory mechanisms are poorly defined in human studies. Investigation of key pathogenic mechanisms requires the use of pre-clinical models, for instance for time-resolved studies. Such models must reflect molecular disease processes of importance in patients. Herein we characterized inflammation in NASH patients on the molecular level by transcriptomics and investigated whether key human disease pathways can be recapitulated experimentally in Ldlr-/-.Leiden mice, an established pre-clinical model of NASH. Methods: Human molecular inflammatory processes were defined using a publicly available NASH gene expression profiling dataset (GSE48452) allowing the comparison of biopsy-confirmed NASH patients with normal controls. Gene profiling data from high-fat diet (HFD)-fed Ldlr-/-.Leiden mice (GSE109345) were used for assessment of the translational value of these mice. Results: In human NASH livers, we observed regulation of 65 canonical pathways of which the majority was involved in inflammation (32%), lipid metabolism (16%), and extracellular matrix/remodeling (12%). A similar distribution of pathways across these categories, inflammation (36%), lipid metabolism (24%) and extracellular matrix/remodeling (8%) was observed in HFD-fed Ldlr-/-.Leiden mice. Detailed evaluation of these pathways revealed that a substantial proportion (11 out of 13) of human NASH inflammatory pathways was recapitulated in Ldlr-/-.Leiden mice. Furthermore, the activation state of identified master regulators of inflammation (i.e., specific transcription factors, cytokines, and growth factors) in human NASH was largely reflected in Ldlr-/-.Leiden mice, further substantiating its translational value. Conclusion: Human NASH is characterized by upregulation of specific inflammatory processes (e.g., “Fcgamma Receptor-mediated Phagocytosis in Macrophages and Monocytes,” “PI3K signaling in B Lymphocytes”) and master regulators (e.g., TNF, CSF2, TGFB1). The majority of these processes and regulators are modulated in the same direction in Ldlr-/-.Leiden mice fed HFD with a human-like macronutrient composition, thus demonstrating that specific experimental conditions recapitulate human disease on the molecular level of disease pathways and upstream/master regulators.
Subject
ELSS - Earth, Life and Social Sciences
Life
Healthy Living
Biomedical Innovation
Liver
NASH,
Inflammation
Molecular
Gene expression
Translational
Mouse
Human
Translational
Cytokine
Growth factor
Transcription factor
Animal experiment
Animal model
Controlled study
Extracellular matrix
Gene expression profiling
Human tissue
Inflammation
Lipid diet
Lipid metabolism
Liver biopsy
Mouse
Nonalcoholic fatty liver
Nonhuman
Transcriptomics
MHR - Metabolic Health Research
To reference this document use:
http://resolver.tudelft.nl/uuid:fb382099-c3e2-4129-90b6-1b06132c2454
DOI
https://doi.org/10.3389/fphys.2018.00132
TNO identifier
787078
Source
Frontiers in Physiology, 9 (9), 1-13
Document type
article