Title THE ROLE OF αSMA< -EXPRESSING >PERIVASCULAR
CELLS DURING REPARATIVE
DENTINOGENESIS Title (croatian) ULOGA αSMA PERIVASKULARNIH
STANICA TIJEKOM STVARANJA
TERCIJARNOG DENTINA Author Ivana Vidović Zdrilić Mentor Alen Braut (mentor)Committee member Ivana Brekalo Pršo (predsjednik povjerenstva)Committee member Ivica Anić (član povjerenstva)Committee member Bojan Polić (član povjerenstva)Committee member Alen Braut (član povjerenstva)Granter University of Rijeka Defense date and country 2020, Croatia Scientific / art field, BIOMEDICINE AND HEALTHCARE Universal decimal classificationUDC ) 616.31 - Stomatology ThesaurusMESH - Medical Subject Headings )
Dentinogenesis
Fibroblast Growth Factor 2
Odontoblasts
Regeneration
Abstract OBJECTIVES: The aim of this study was to examine the contribution of perivascular
cells to odontoblasts during the development, growth, and repair of dentin and examine
the effects of early and limited exposure of perivascular cells to fibroblast growth factor
2 (FGF2) in vivo using mouse molars as a model. MATERIAL AND METHODS: We
used an inducible, Cre-loxP in vivo fate-mapping approach to examine the contributions
of the descendants of cells expressing the αSMA-CreERT2 transgene to the odontoblast
lineage. RESULTS: In vivo lineage-tracing experiments showed the contribution of
αSMA-tdTomato+ cells to a small number of newly formed odontoblasts during primary
dentinogenesis. Experiments revealed that mild injury to dentin first led to activation of
aSMA-tdTomato+ cells in the entire pulp chamber. After their activation aSMAtdTomato+
cells migrated towards the site of injury, gave rise to pulp cells and a few
odontoblasts that became integrated into the existing odontoblast layer expressing Col2.3-
GFP and Dspp. Using an experimental pulp exposure model in molars to induce
reparative dentinogenesis, we demonstrate the contribution of αSMA-tdTomato+ cells to
cells secreting reparative dentin. Our results demonstrate that αSMA-tdTomato+ cells
differentiated into Col2.3-GFP+ cells composed of both Dspp+ odontoblasts and Bsp+
osteoblasts. Early delivery of exogenous FGF2 to exposed pulp led to proliferative
expansion of αSMA-tdTomato+ cells and their accelerated differentiation into
odontoblasts. Results showed that the calcified bridge/reparative dentin in FGF2-treated
pulps were lined with an increased number of Dspp+ odontoblasts and devoid of BSP+
osteoblasts. CONCLUSION: Our findings identify a population of mesenchymal
progenitor cells capable of giving rise to a second generation of odontoblasts during
reparative dentinogenesis. The increased number of odontoblasts derived from αSMAtdTomato+
cells and the formation of reparative dentin devoid of osteoblasts provide in
vivo evidence for the stimulatory effects of FGF signaling on odontoblast differentiation
from early progenitors in dental pulp.
Abstract (croatian) CILJ ISTRAŽIVANJA: Reparativna dentinogeneza je regenerativni proces koji dovodi
do stvaranja dentinskog mineraliziranog mosta koji pridonosi održavanju vitaliteta zubne
pulpe. Reparativna dentinogeneza nastaje nakon intenzivne ozljede dentina koja dovodi
do smrti odontoblasta i uključuje aktivaciju, proliferaciju i migraciju mezenhimnih
matičnih stanica do mjesta ozljede i njihovu diferencijaciju u drugu generaciju
odontoblasta i odontoblastima – sličnim stanica. Identitet stanica kćeri stanica i signalni
putovi uključenih u proces reparativne dentinogeneze su još uvijek nedovoljno istraženi
i nepoznati. Cilj ove studije je ispitati ulogu perivaskularnih stanica u pulpi koja
eksprimira alfa aktin glatkog mišića-GFP (αSMA-GFP) u reparativnoj dentinogenezi i
ispitati učinke FGF signalne molekule na ovu populaciju. Koristili smo inducirani CreloxP
rekombinacijski sustav (αSMA-CreERT2) za eksperimente praćenja staničnih loza
in vivo i in vitro. Cilj je ispitati doprinos perivaskularnih stanica odontoblastima tijekom
razvoja, rasta i regeneracije dentina i ispitati učinke rane i ograničene izloženosti
perivaskularnih stanica fibroblastičnom faktoru rasta 2 (FGF2) in vivo na uzorku mišjih
kutnjaka. MATERIJALI I METODE: Koristili smo inducirani, Cre-loxP in vivo pristup
praćenja sudbine stanica da bismo ispitali doprinos potomaka stanica koji izražavaju
αSMA-CreERT2 transgen u odontoblastastičnoj liniji. REZULTATI: Pokusi in vivo
praćenja loze na kutnjacima pokazali su doprinos αSMA-tdTomato+ stanica malom broju
novoformiranih odontoblasta tijekom primarne dentinogeneze. Eksperimenti su otkrili da
je blaga trauma dentina najprije dovela do aktivacije SMA-tdTomato+ stanica u cijeloj
pulpnoj komori. Postotak područja koja zauzimaju SMA-tdTomato+ stanice u zubima sa
traumom dentina bio je značajno veći nego kod zuba bez ozljeda. Nakon njihove
aktivacije SMA-tdTomato+ stanice migrirale su prema mjestu ozljede, diferencirale u
pulpne stanice, te su nekoliko SMA-tdTomato+ odontoblasta koji su se integrirali u
postojeći odontoblastni sloj izražavali Col2.3-GFP i Dspp. Koristeći eksperimentalni
model direktnog prekrivanja pulpe u kutnjacima kako bi potakli reparativnu
dentinogenezu, prikazali smo doprinos αSMA-tdTomato+ stanica stanicama koje izlučuju
reparativni dentin. Naši rezultati pokazuju da su se αSMA-tdTomato+ stanice
diferencirale u Col2.3-GFP+ stanice, te su sastavljene od Dspp+ odontoblasta i Bsp+
osteoblasta. Rana primjena egzogenog FGF2 nakon direktnog prekrivanja pulpe dovela
je do jače proliferacije αSMA-tdTomato+ stanica i njihove ubrzane diferencijacija u
odontoblaste. Rezultati su pokazali da je mineralizirani most reparativng dentina u
kutnjacima tretiranim FGF2-om obložen povećanim brojem Dspp+ odontoblasta uz
odsudstvo BSP+ osteoblasta. ZAKLJUČAK: Blaga ozljeda dovela je do aktivacije
perivaskularnih SMA-tdTomato+ stanica koje su diferencirale u stanice pulpe, kao i
nekoliko odontoblasta koji su integrirani u prethodno postojeći sloj odontoblasta. Naši
nalazi identificiraju populaciju mezenhimalnih potomskih stanica koje mogu stvoriti
drugu generaciju odontoblasta (odontoblastima – slične stanice) tijekom reparativne
dentinogeneze. Povećani broj odontoblasta dobivenih iz αSMA-tdTomato+ stanica i
stvaranje reparativnog dentina lišenog osteoblasta pružaju in vivo dokaze za stimulacijske
učinke signalizacije FGF2-a na diferencijaciju odontoblasta u zubnoj pulpi.
Keywords
Dentin
Fibroblast growth factor
Odontoblasts
Pericytes
Regeneration
Keywords (croatian)
Dentin
Fibroblastični faktor rasta
Odontoblasti
Pericite
Regeneracija
Language english URN:NBN urn:nbn:hr:184:092101 Promotion 2020 Study programme Title: Biomedicine Postgraduate (doctoral) study programme Type of resource Text File origin Born digital Access conditions Access restricted to students and staff of home institution Terms of use Public note Ispravan naslov rada: THE ROLE OF αSMA -EXPRESSING PERIVASCULAR
CELLS DURING REPARATIVE
DENTINOGENESIS Repository Repository of the University of Rijeka, Faculty of Medicine Created on 2020-10-15 06:50:38
