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.