Project description:Primary mitochondrial disease (PMD) patients manifesting cardiomyopathy are twice as likely to die as other PMD patients. One PMD with cardiomyopathy is caused by null mutations in the heart-muscle isoform of the adenine nucleotide translocator (ANT1) gene, the severity of the cardiomyopathy being mediated by the mitochondrial DNA (mtDNA). To perfect strategies for addressing mitochondria cardiomyopathy, we generated an Ant1 null mouse and combined it with our ND6P25L mtDNA mutation to mimic the hypertrophic versus dilated cardiomyopathies observed in patients, respectively. We then transduced the neonatal Ant1-/- and Ant1-/-+ND6P25L mouse hearts with an AAV9-pDesmin-GFP-Ant1 cDNA vector. Restoration of just 10% Ant1 gene expression was sufficient to ameliorate the cardiomyopathies in these mice. Proteomics and single nucleus RNA sequencing (snRNA-seq) revealed the reversal of dysregulated mitochondrial metabolic genes including PGC1α as well as cardiac contractile and extracellular matrix proteins. Hence, modest increase in cardiac mitochondrial energetics can have profound benefits on cardiac function and is effective in treating mitochondrial cardiomyopathy.
Project description:Macrophage-mediated inflammation drives various lung diseases, including chronic obstructive pulmonary disease (COPD). COPD macrophages have dysfunctional mitochondrial metabolism and function which lead to a chronic inflammatory lung environment. However, the factors regulating this altered metabolism have not been elucidated. Adenine nucleotide translocase 1 (ANT1) is a mitochondrial ATP transporter critical to mitochondrial metabolism. We demonstrate that human alveolar macrophages from patients with moderate COPD (GOLD stage 2) have reduced ANT1 expression while macrophages from very severe COPD (GOLD stage 4) has elevated ANT1 compared to normal control subjects. Ant1-deficient mice were protected against cigarette smoke (CS)-induced emphysema with failure of recruited immune cells to migrate into alveoli. Ant1-null alveolar macrophages had reduced ATP production and mitochondrial respiration, upregulated fewer inflammatory pathways after CS and reduced migratory capacity. Conditional Ant1 knockout in Cx3cr1-positive monocytes and adoptive transfer of Ant1-deficient bone marrow into CS-treated mice phenocopied the migratory defect in the lung. Our data indicate that ANT1 is a critical regulator of lung macrophage inflammatory signaling and CS-triggered cell migration in the lung, suggesting that metabolic modulation may be a promising therapeutic avenue for COPD
Project description:Macrophage-mediated inflammation drives various lung diseases, including chronic obstructive pulmonary disease (COPD). COPD macrophages have dysfunctional mitochondrial metabolism and function which lead to a chronic inflammatory lung environment. However, the factors regulating this altered metabolism have not been elucidated. Adenine nucleotide translocase 1 (ANT1) is a mitochondrial ATP transporter critical to mitochondrial metabolism. We demonstrate that human alveolar macrophages from patients with moderate COPD (GOLD stage 2) have reduced ANT1 expression while macrophages from very severe COPD (GOLD stage 4) has elevated ANT1 compared to normal control subjects. Ant1-deficient mice were protected against cigarette smoke (CS)-induced emphysema with failure of recruited immune cells to migrate into alveoli. Ant1-null alveolar macrophages had reduced ATP production and mitochondrial respiration, upregulated fewer inflammatory pathways after CS and reduced migratory capacity. Conditional Ant1 knockout in Cx3cr1-positive monocytes and adoptive transfer of Ant1-deficient bone marrow into CS-treated mice phenocopied the migratory defect in the lung. Our data indicate that ANT1 is a critical regulator of lung macrophage inflammatory signaling and CS-triggered cell migration in the lung, suggesting that metabolic modulation may be a promising therapeutic avenue for COPD