Prnp Deletion Mitigates Muscle Fiber Type‐Specific Sarcopenia Induced by Prion Infection in Mice

Recent studies have shown that significant expression of PrPC protein is also present in skeletal muscle, and it plays a significant role in maintaining skeletal muscle homeostasis. Although the expression of PrPC in skeletal muscle has been clarified, the effects of PrPSc-mediated prion protein infection on sarcopenia in mice and its potential regulatory mechanisms remain unclear. This study investigated the role of PrPC in Prion-induced sarcopenia, using an animal model of prion disease based on intraperitoneal injection of the scrapie strain ME7 into wild-type mice and Prnp knockout mice. The results indicate that prion infection-induced sarcopenia exhibits muscle fiber type specificity, and that the lack of PrPC can prevent prion protein infection-induced sarcopenia, although the lack of PrPC may lead to reduced mitochondrial-endoplasmic reticulum homeostasis. These data provide novel evidence that prion infection affects skeletal muscle system health through myofiber-specific mechanisms.