Extracellular vesicles through the blood– brain barrier: a review

El hondureño Héctor Ramos (Director GIMUNICAH) junto a científicos chilenos (Edison Salas‑Huenuleo, Alejandro H. Corvalán, Claudia P. Yefi, Marcelo E. Andia), argentinos (Marcelo J. Kogan) y de República Checa (Iva Polakovicova) publicó en la revista Fluids and Barriers of the CNS el artículo con título "Extracellular vesicles through the blood– brain barrier: a review".

Compartimos el link y las figuras para los interesados en conocer sobre cómo las vesículas extracelulares atraviesan la barrera hematoencefálica para llegar al cerebro y algunas teorías en las que trabajan actualmente.

Artículo completo: https://rdcu.be/cSn5U

Fig. 1 Uptake and transcytosis mechanisms for crossing of extracellular vesicles through the BBB. The figure shows four uptake mechanisms that have been evaluated and proposed for the active transport of EVs across the BBB and the authors that have described evidence to support them: A Macropinocytosis. B Clathrin‑mediated endocytosis. C Caveolae‑mediated endocytosis. D Adsorptive‑mediated endocytosis. The fate of EVs after internalization include recycling to the plasma membrane, degradation of EVs by lysosomes, and final transcytosis of EVs and their cargos to the extracellular space. EVs extracellular vesicles, BBB blood brain barrier, MVB multivesicular body, TJ tight junctions

Fig. 2 Comparison of BBB structures of zebrafish, mice, and humans. The figure shows the main components of the BBB, including endothelial cells with specialized tight junctions, pericytes, and astrocytic or glial processes. A The zebrafish BBB has a less complex neurovascular unit that lacks classic stellate astrocytes, with radial glial processes that rarely become in contact with the vasculature. B The mouse BBB presents astrocytic end feet in close contact with the vasculature. C Compared to mice, the human BBB shows a greater number of astrocytic end feet. Also shown are the in vitro and in vivo models that have evaluated direct visualization of EVs transcytosis through the BBB in these species. EVs extracellular vesicles, BBB blood brain barrier, EM-CCD electron multiplication charge‑coupled device, TNF-α tumor necrosis factor alpha, LPS lipopolysaccharide

Fig. 3 Anatomical pathways and barriers of the CNS as potential routes for extracellular vesicles. The figure shows theoretical vascular points of entrance for EVs and checkpoint barriers to the brain parenchyma that should be further examined. A The classical path that has been evaluated for EVs crossing from peripherical blood to the brain is through arterial flow and the BBB, comprised of endothelial cells, pericytes, and astrocytes. B The recently discovered meningeal lymphatic vessels expose a route to the CSF‑brain barrier not yet explored and that EVs could exploit to access the brain parenchyma. C A third entrance point is through the Blood‑CSF barrier at the choroid plexus. EVs: extracellular vesicles; BBB: blood brain barrier; CNS: Central Nervous System; CSF: cerebrospinal fluid