PRNP and ischemic disease: Our previous studies indicate that melatonin increases the regenerative potential of MSCs in ischemic disease and CKD through upregulation of cellular prion protein (PrPC) which is involved in self‐renewal, differentiation, and angiogenesis in stem and/or progenitor cells (Doeppner et al., 2015; Han et al., 2019; Lee, Han, & Lee, 2017).