Mimp/Mtch2, an Obesity Susceptibility Gene, Induces Alteration of Fatty Acid Metabolism in Transgenic Mice

OBJECTIVE: Metabolic dysfunctions, such as fatty liver, obesity and insulin resistance, are among the most common contemporary diseases worldwide, and their prevalence is continuously rising. Mimp/Mtch2 is a mitochondrial carrier protein homologue, which localizes to the mitochondria and induces mitochondrial depolarization. Mimp/Mtch2 single-nucleotide polymorphism is associated with obesity in humans and its loss in mice muscle protects from obesity. Our aim was to study the effects of Mimp/Mtch2 overexpression in vivo. METHODS: Transgenic mice overexpressing Mimp/Mtch2-GFP were characterized and monitored for lipid accumulation, weight and blood glucose levels. Transgenic mice liver and kidneys were used for gene expression analysis. RESULTS: Mimp/Mtch2-GFP transgenic mice express high levels of fatty acid synthase and of β-oxidation genes and develop fatty livers and kidneys. Moreover, high-fat diet–fed Mimp/Mtch2 mice exhibit high blood glucose levels. Our results also show that Mimp/Mtch2 is involved in lipid accumulation and uptake in cells and perhaps in human obesity. CONCLUSIONS: Mimp/Mtch2 alters lipid metabolism and may play a role in the onset of obesity and development of insulin resistance.