Due to unknown reasons, MC1R activation seems to be insufficient to protect against podocytopathy in vivo in rodent models like the ADN model (Lindskog Jonsson et al., 2014) or possibly in the PAN model here, although MC1R agonism did successfully protect against podocyte injury in vitro (Elvin et al., 2016; Bergwall et al., 2018). This evidence concerns the gene MC1R and polyarteritis nodosa.