MFN2 and chronic kidney disease: However, this tendency changes along with CKD progression; in fact, our results showed that DRP1 increased 28 days after surgery (Figure 3A,B) and fusion proteins MFN2 and OPA1 started to increase from day 2 (Figure 3A,C), whereas mitochondrial fragmentation was observed by electron microscopy after day 7 (Figure 4).