Interrogating the interconnected biological networks in liver diseases reveals the core components of a perturbed homeostatic system.

Abstract

This thesis explores the interplay between genetics, environment, and immunological regulation in metabolic associated fatty liver disease (MAFLD), metabolic steatohepatitis (MeSH), and hepatocellular carcinoma (HCC), focusing on liver response to dietary exposome and bone marrow hematopoietic stem and progenitor cells (HSPCs) activity. Using weighted gene co-expression network analysis (WGCNA), we assessed mRNA expression in murine models and human datasets, identifying conserved metabolic and immunological programs and discrepancies in immune responses. The heightened immune response in certain mouse models, reflective of bone marrow HSPCs response, is found protective and consistent with human data, emphasizing the crucial role of immune system-tumorigenesis interplay.

Investigating regulatory factors, we spotlight bile acids’ significance. Maintaining a robust immune response is linked to reduced liver tumor burden, with HSPC dietary response as a potential regulatory factor. While cholesterol homeostasis disruptions alone don’t stimulate HSPCs, when combined with disrupted bile acid homeostasis, they significantly impact HSPCs. Rescuing bile acid synthesis dampens HSPC activity, underscoring bile acids' regulatory role.

Our findings provide valuable insights into the intricate regulatory networks governing liver disease, presenting potential new avenues for research, including exploring bile acid metabolism’s direct regulation of bone marrow HSPCs, assessing the long-term impact of HSPC stimulation, and investigating liver cholesterol homeostasis’s effect on immunotherapy response. This research suggests exploration of minimal therapeutics targeting sensitive targets and context-driven interpretation in animal model extrapolation. Overall, our experimental approach shows potential in aiding the development of effective treatments for liver diseases, paving the way for future studies in this field.