Exosomal microRNAs in common mental disorders: Mechanisms, biomarker potential and therapeutic implications

Figure 1 Exosome content and endosome sorting complex required for transport are involved in the biogenesis of exosomal microRNAs. Exosomes originate from the endosomal system, beginning with early endosome formation via plasma membrane endocytosis. As endosomes mature into late endosomes, they develop into multivesicular bodies through inward budding of the limiting membrane, a process regulated by the endosome sorting complex required for transport machinery. Key regulators and cargo classes are annotated to illustrate exosomes’ dual roles as intercellular messengers and diagnostic/therapeutic targets in diseases. MVB: Multivesicular body; MHC: Major histocompatibility complex; ESCRT: Endosome sorting complex required for transport; CD: Cluster of differentiation; HSP: Heat shock protein; miRNA: MicroRNA; circRNA: Circular RNA; lncRNA: Long non-coding RNA; mRNA: Message RNA.

Figure 2 The mechanism of exosomal microRNAs in mental disorders. Including intercellular communication, neurogenesis, synaptic plasticity, inflammatory response, mitochondrial function in the brain, and stress response. miRNA: MicroRNA; APC: Antigen presenting cell; BDNF: Brain-derived neurotrophic factor.

Figure 3 The exosomal microRNAs signaling pathways of mental disorders. Including toll-like receptor 4, phosphatidylinositol 3-kinase/protein kinase B, Ras/GSK-3β signaling pathways. miRNA: MicroRNA; TLR4: Toll-like receptor 4; TRIF: Toll/interleukin-1 receptor domain-containing adaptor inducing interferon-β; TRAM: Toll/interleukin-1 receptor domain-containing adaptor molecule; TIRAP: Toll-interleukin 1 receptor domain-containing adapter protein; PI3K: Phosphatidylinositol 3-kinase; Akt: Protein kinase B; MEK: Mitogen-activated extracellular signal-regulated kinase; ERK: Extracellular regulated protein kinases; mTOR: Mammalian target of rapamycin; MAP: Microtubule-associated protein; NF-kB: Nuclear factor kappa-B.