SEMA4C and fibrosis: Increased expression of circNlgn led to compromised cardiac function and enhanced cardiac fibrosis by upregulating growth arrest and DNA damage inducible protein 45 b (Gadd45b), semaphorin-4C (Sema4C), and RAD50 and activating p38 and p-JNK via its translated Nlgn173 in transgenic hearts.