In mice given ANG2, it causes hypotrophy, fibrosis, and heart failure (Table 3) and it stimulates mitochondrial fusion in SIRT4-transfected HEK293 and fibroblast cells, inhibits mitophagy through linking to the protein ocular atrophy 1 (OPA1), and increases ROS buildup by connecting with SIRT3, which stops SIRT2 from activating (Han et al., 2019; Eid et al., 2021). The gene discussed is SIRT4; the disease is heart failure.