Research Article Details

Article ID: A49550
PMID: 35718058
Source: Am J Pathol
Title: Dysregulation of Lipid and Glucose Homeostasis in Hepatocyte-Specific SLC25A34 Knockout Mice.
Abstract: Nonalcoholic fatty liver disease (NAFLD) is an epidemic affecting 30% of the US population. NAFLD is characterized by insulin resistance and by defective lipid metabolism and mitochondrial dysfunction in the liver. SLC25A34 is a major repressive target of miRNA-122, a miRNA that has a central role in NAFLD and liver cancer. However, little is known about the function of SLC25A34. To investigate SLC25A34 in vitro, mitochondrial respiration and bioenergetics were examined using hepatocytes depleted of Slc25a34 or overexpressing Slc25a34. To test the function of SLC25A34 in vivo, a hepatocyte-specific knockout mouse was generated, and loss of SLC25A34 was assessed in mice maintained on a chow diet and a fast-food diet (FFD), a model for NAFLD. Hepatocytes depleted of Slc25a34 displayed increased mitochondrial biogenesis, lipid synthesis, and ADP/ATP ratio; Slc25a34 overexpression had the opposite effect. In the knockout model on chow diet, SLC25A34 loss modestly affected liver function (altered glucose metabolism was the most pronounced defect). RNA-sequencing revealed changes in metabolic processes, especially fatty acid metabolism. After 2 months of FFD, knockouts had a more severe phenotype, with increased lipid content and impaired glucose tolerance, which was attenuated after longer FFD feeding (6 months). This work thus presents a novel model for studying SLC25A34 in vivo in which SLC25A34 plays a role in mitochondrial respiration and bioenergetics during NAFLD.
DOI: 10.1016/j.ajpath.2022.06.002