ǂThe ǂrole of SOX2 and SOX9 genes and miR-21 in phenotypical characteristics of astrocytes derived from pluripotent NT2/D1 cells

[V. Balint]

83 str.

Biologija - Molekularna biologija / Biology - Molecular biology

Astrociti su glavne homeostatske ćelije centralnog nervnog sistema (CNS), sa jedinstvenom sposobnošću da se aktiviraju u odgovoru na različita patološka stanja CNS-a. Poznato je da tokom procesa aktivacije ponovo stiču određene osobine astrocitnih prekursora, uključujući ponovnu ekspresiju regulatornih proteina SOX2 i SOX9. Iako su uloge SOX2 i SOX9 u gliogenezi poznate, njihove funkcije u zrelim astrocitima nisu u potpunosti razjašnjene. MikroRNK (miRNK) predstavljaju bitne regulatore različitih funkcija astrocita, pri čemu miR-21 ima značajnu ulogu u reaktivnoj astrogliozi. Međutim, njena uloga u drugoj značajnoj fenotipskoj promeni astrocita, senescenciji, nije poznata. Primenom lentiviralne transdukcije, imunofluorescencije i Western blot-a na astrocitima poreklom od NT2/D1 ćelija (NT2/A) ispitane su uloge SOX2, SOX9 i miR-21 u fenotipskim osobinama astrocita, sa fokusom na procese aktivacije i senescencije. Rezultati su pokazali da SOX2 povećava proliferativni kapacitet NT2/A, dok SOX9 povećava migratorni kapacitet. Takodje, pokazano je da SOX9 povećava ekspresiju NFIA i glutamatnog transportera GLAST kao i da dovodi do povećanja kapaciteta za preuzimanje vanćelijskog glutamata u zrelim astrocitima. Sa druge strane, utišavanje miR-21 smanjuje proliferaciju astrocita i potencijalno pomaže njihov ulazak u senescenciju. Naši rezultati pokazuju da SOX2, SOX9 i miR-21 ostvaruju bitne uloge u procesima aktivacije i senescencije astrocita. Razumevanje njihovog uticaja na fenotipske karakteristike astrocita vezanih za aktivaciju i senescenciju otvara mogućnost za njihovu modulaciju koja bi potencijalno mogla doprineti razvoju novih terapeutskih strategija za regeneraciju tkiva i oporavak CNS-a.

Astrocytes are the primary homeostatic cells of the central nervous system (CNS), with a unique ability to reactivate in response to various pathological disorders of the CNS. During the reactivation process, they reacquire certain characteristics of astrocytic precursors, including re-expression of the transcription factors SOX2 and SOX9. While the roles of SOX2 and SOX9 in gliogenesis are well known, their functions in mature astrocytes remain incompletely understood. MicroRNAs (miRNAs) are key regulators of various astrocytic functions, with miR-21 playing a significant role in reactive astrogliosis. However, its role in another major phenotypic change in astrocytes, senescence, is unknown. Lentiviral transduction, immunofluorescence, and Western blot analysis were employed to investigate the roles of SOX2, SOX9, and miR-21 in the phenotypic properties of astrocytes derived from NT2/D1 cells (NT2/A), with the focus on the processes of reactivation and senescence. Our results showed that SOX2 increases the proliferative capacity of NT2/A, while SOX9 increases their migratory capacity. SOX9 also increases the expression of NFIA and the glutamate transporter GLAST, as well as the capacity for extracellular glutamate uptake in mature astrocytes. Silencing miR-21 reduces astrocyte proliferation and potentially promotes their senescence. Our findings indicate that SOX2, SOX9, and miR-21 play critical roles in the processes of astrocyte reactivation and senescence. Understanding the influence of these factors on astrocyte phenotypic characteristics related to reactivation and senescence opens the possibility for their modulation, which could potentially contribute to the development of novel therapeutic strategies for tissue regeneration and CNS recovery.

astrociti, SOX2, SOX9, NT2/D1, miR-21, senescencija, reaktivna astroglioza, proliferacija, migracija, glutamat

SOX2, SOX9, astrocytes, NT2/D1, miR-21, senescence, reactive astrogliosis, proliferation, migration, glutamate

577.27:612.8(043.3)

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