Fig. 4
From: MiRNAs as potential therapeutic targets and biomarkers for non-traumatic intracerebral hemorrhage
Types and pathways of microRNA (miRNAs) secretion into the extracellular space/biofluids. MiRNAs that can be secreted from cells are called circulating or extracellular or cell-free miRNAs. To date, two secretion pathways are known: 1) passive secretion from damaged cells due to apoptosis or necrosis and 2) active secretion with the help of extracellular vesicles (EVs), including exosomes and microvesicles (MVs), as part of low-density lipoproteins (LDL) or using an RNA-binding protein-dependent pathway (complex of miRNA-Argonaute 2 (Ago2) or miRNA- nucleophosmin (NPM1)). Note: pri-miRNA, primary microRNA; pre-miRNA, precursor microRNA; XPO5, Exportin 5; RISC, RNA-induced silencing complex; ER, Endoplasmic reticulum; MVE, Multivesicular endosomes