α-Lipoic acid ameliorates mitochondrial impairment and reverses apoptosis in FABP3-overexpressing embryonic cancer cells

Fatty acid-binding protein 3 (FABP3) is a low molecular weight protein with distinct tissue distribution, which may play an important role in fatty acid transport, cell growth, cellular signaling, and gene transcription. We have previously shown FABP3 was more highly expressed in myocardium with ventricular septal defects than in normal myocardium and furthermore, that overexpression of FABP3 causes mitochondrial dysfunction and induces apoptosis in the P19 mouse teratocarcinoma cell line (P19), which is a suitable model for the investigation of cardiac differentiation at the molecular and functional levels. α-Lipoic acid (α-LA), a natural dithiol compound with antioxidant properties, has been reported to protect mitochondrial function in cells. In this study, we established an FABP3-overexpressing P19 cell line for the investigation of the impact of α-LA on mitochondrial impairment and apoptosis in these cells. Mitochondrial morphology was evaluated by transmission electron microscopy, while the effects of α-LA on reactive oxygen species (ROS) production, mitochondrial membrane potential (MMP), intracellular ATP content and the amount of mitochondrial DNA were analyzed by flow cytometry, a commercially available assay and quantitative real-time PCR, respectively. The results revealed that α-LA ameliorated mitochondrial deformation and decreased intracellular ROS production. Furthermore, the MMP, intracellular ATP synthesis and the amount of mitochondrial DNA were also increased. Most significantly, α-LA was shown to reverse apoptosis. Collectively, our results indicate that abnormalities in FABP3 expression contribute to mitochondrial dysfunction and apoptosis, and that α-LA represents a suitable candidate for development as a treatment for apoptosis-related congenital cardiac malformations.