Mitochondrial fission was also shown to play a progressive role in obesity-induced cardiac fibrosis in obese minipigs (Chen et al., 2020a); as with the above-mentioned studies, the authors used the H9C2 cardiomyocyte line and not CF as the in vitro model, which could not recapitulate the importance of mitochondrial fission in CF. The gene discussed is CFTR; the disease is obesity due to melanocortin 4 receptor deficiency.